38770821
The TERT promoter mutation incidence is modified by germline TERT rs2736098 and rs2736100 polymorphisms in hepatocellular carcinoma
Telomerase activation via induction of the catalytic component telomerase reverse transcriptase (TERT) plays essential roles in malignant transformation. TERT promoter-activating mutations were recently identified as a novel mechanism to activate telomerase in hepatocellular carcinoma (HCC) and many other malignancies. In addition, single nucleotide polymorphisms (SNPs) in the TERT rs2736098 and rs2736100 are significantly associated with cancer susceptibility. It is currently unclear whether different germline TERT variants modify TERT promoter mutations. Here we analyzed the TERT promoter status and genotyped the TERT SNPs at rs2736098 and rs2736100 in patients with HCC. Thirty percent of HCCs harbored TERT promoter mutations and there was a significant difference in rs2736098 and rs2736100 genotypes between wt and mutant TERT promoter-bearing HCC tumors (P = 0.007 and 0.018, respectively). For rs2736100, the cancer risk genotype CC was significantly associated with a reduced incidence of TERT promoter mutations compared to AA + AC variants [Odds ratio (OR): 0.181, 95% Confidence interval (CI): 0.0543–0.601, P = 0.004]. The rs2736098_CT genotype was significantly associated with the TERT promoter mutation-positive tumors compared to the TT genotype (OR: 5.391, 95% CI: 1.234–23.553, P = 0.025). These differences in genotype distribution did not differ between patients with a wt TERT promoter and controls. The presence of TERT promoter mutations was not associated with clinico-pathological variables. Taken together, the germline TERT genetic background may significantly affect the onset of TERT promoter mutations in HCCs, which provides a better understanding of HCC-related TERT promoter mutations and telomerase regulation in cancer.
7867443
Molecular alterations in hepatocellular carcinoma associated with hepatitis B and hepatitis C infections
Chronic infections with hepatitis B (HBV) and hepatitis C viruses (HCV) are the leading cause of cirrhosis and hepatocellular carcinoma (HCC) worldwide. Both viruses encode multifunctional regulatory proteins activating several oncogenic pathways, which induce accumulation of multiple genetic alterations in the infected hepatocytes. Gene mutations in HBV- and HCV-induced HCCs frequently impair the TP53, Wnt/b-catenin, RAS/RAF/MAPK kinase and AKT/mTOR pathways, which represent important anti-cancer targets. In this review, we highlight the molecular mechanisms underlying the pathogenesis of primary liver cancer, with particular emphasis on the host genetic variations identified by high-throughput technologies. In addition, we discuss the importance of genetic alterations, such as mutations in the telomerase reverse transcriptase (TERT) promoter, for the diagnosis, prognosis, and tumor stratification for development of more effective treatment approaches.
22809130
Genetic Landscape and Biomarkers of Hepatocellular Carcinoma.
Hepatocellular carcinoma (HCC) has emerged as a major cause of cancer-related death. Its mortality has increased in Western populations, with a minority of patients diagnosed at early stages, when curative treatments are feasible. Only the multikinase inhibitor sorafenib is available for the management of advanced cases. During the last 10 years, there has been a clear delineation of the landscape of genetic alterations in HCC, including high-level DNA amplifications in chromosome 6p21 (VEGFA) and 11q13 (FGF19/CNND1), as well as homozygous deletions in chromosome 9 (CDKN2A). The most frequent mutations affect TERT promoter (60%), associated with an increased telomerase expression. TERT promoter can also be affected by copy number variations and hepatitis B DNA insertions, and it can be found mutated in preneoplastic lesions. TP53 and CTNNB1 are the next most prevalent mutations, affecting 25%-30% of HCC patients, that, in addition to low-frequency mutated genes (eg, AXIN1, ARID2, ARID1A, TSC1/TSC2, RPS6KA3, KEAP1, MLL2), help define some of the core deregulated pathways in HCC. Conceptually, some of these changes behave as prototypic oncogenic addiction loops, being ideal biomarkers for specific therapeutic approaches. Data from genomic profiling enabled a proposal of HCC in 2 major molecular clusters (proliferation and nonproliferation), with differential enrichment in prognostic signatures, pathway activation and tumor phenotype. Translation of these discoveries into specific therapeutic decisions is an unmet medical need in this field.
25457422
Regulation of the human catalytic subunit of telomerase (hTERT).
Over the past decade, there has been much interest in the regulation of telomerase, the enzyme responsible for maintaining the integrity of chromosomal ends, and its crucial role in cellular immortalization, tumorigenesis, and the progression of cancer. Telomerase activity is characterized by the expression of the telomerase reverse transcriptase (TERT) gene, suggesting that TERT serves as the major limiting agent for telomerase activity. Recent discoveries have led to characterization of various interactants that aid in the regulation of human TERT (hTERT), including numerous transcription factors; further supporting the pivotal role that transcription plays in both the expression and repression of telomerase. Several studies have suggested that epigenetic modulation of the hTERT core promoter region may provide an additional level of regulation. Although these studies have provided essential information on the regulation of hTERT, there has been ambiguity of the role of methylation within the core promoter region and the subsequent binding of various activating and repressive agents. As a result, we found it necessary to consolidate and summarize these recent developments and elucidate these discrepancies. In this review, we focus on the co-regulation of hTERT via transcriptional regulation, the presence or absence of various activators and repressors, as well as the epigenetic pathways of DNA methylation and histone modifications.
2959406
Human Telomerase and Its Regulation
SUMMARY The telomere is a special functional complex at the end of linear eukaryotic chromosomes, consisting of tandem repeat DNA sequences and associated proteins. It is essential for maintaining the integrity and stability of linear eukaryotic genomes. Telomere length regulation and maintenance contribute to normal human cellular aging and human diseases. The synthesis of telomeres is mainly achieved by the cellular reverse transcriptase telomerase, an RNA-dependent DNA polymerase that adds telomeric DNA to telomeres. Expression of telomerase is usually required for cell immortalization and long-term tumor growth. In humans, telomerase activity is tightly regulated during development and oncogenesis. The modulation of telomerase activity may therefore have important implications in antiaging and anticancer therapy. This review describes the currently known components of the telomerase complex and attempts to provide an update on the molecular mechanisms of human telomerase regulation.
16313766
Cancer-Specific Telomerase Reverse Transcriptase (TERT) Promoter Mutations: Biological and Clinical Implications
The accumulated evidence has pointed to a key role of telomerase in carcinogenesis. As a RNA-dependent DNA polymerase, telomerase synthesizes telomeric DNA at the end of linear chromosomes, and attenuates or prevents telomere erosion associated with cell divisions. By lengthening telomeres, telomerase extends cellular life-span or even induces immortalization. Consistent with its functional activity, telomerase is silent in most human normal somatic cells while active only in germ-line, stem and other highly proliferative cells. In contrast, telomerase activation widely occurs in human cancer and the enzymatic activity is detectable in up to 90% of malignancies. Recently, hotspot point mutations in the regulatory region of the telomerase reverse transcriptase (TERT) gene, encoding the core catalytic component of telomerase, was identified as a novel mechanism to activate telomerase in cancer. This review discusses the cancer-specific TERT promoter mutations and potential biological and clinical significances.
42306672
TERT promoter mutation in resectable hepatocellular carcinomas: a strong association with hepatitis C infection and absence of hepatitis B infection.
INTRODUCTION
Mutation in the core promoter of the telomerase reverse transcriptase (TERT) gene was determined to be a frequent event in malignant melanoma and other cancers. However, the role of TERT promoter mutation in hepatocellular carcinomas (HCCs) remains largely unknown.


METHODS
Genomic DNA samples from the tumor tissue of 195 HCCs were analyzed for TERT promoter mutation at 2 hotspots (-124 and -146 bp from the ATG start site, g.1,295,228 and g.1,295,250, respectively) through direct sequencing.


RESULTS
The TERT promoter mutation was identified in 57 of the 195 HCCs (29.2%) and was associated with old age (P = 0.0122), presence of anti-hepatitis C (HCV; P = 0.0048), and absence of hepatitis B surface antigen (HBsAg; P = 0.0007). However, the TERT promoter mutation did not correlate with serum α-fetoprotein levels, liver cirrhosis, tumor size, tumor grade, tumor stage, early tumor recurrence, β-catenin mutation or p53 mutation. A multivariate analysis confirmed that the absence of hepatitis B infection is an independent factor associated with TERT promoter mutation. Furthermore, among HCC patients infected with hepatitis C, those with concomitant hepatitis B infection exhibited infrequent TERT promoter mutation (P = 0.0435). Remarkably, patients presenting with TERT promoter mutation-positive and -negative HCCs exhibited similar disease-free and overall survival rates.


CONCLUSIONS
Our study indicated that the TERT promoter mutation frequently occurred in HCV-associated HCCs. The absence of Hepatitis B infection was significantly associated with the TERT promoter mutation. These findings suggest that various etiological factors may be involved in differing mechanisms to preserve telomeres during the carcinogenesis of HCCs.
34864999
Comprehensive analyses of mutations and hepatitis B virus integration in hepatocellular carcinoma with clinicopathological features
Background and AimsGenetic alterations in specific genes are critical events in carcinogenesis and hepatocellular carcinoma (HCC) progression. However, the genetic alterations responsible for HCC development, progression, and survival are unclear.MethodsWe investigated the essential difference in genetic alterations between HCC and adjacent non-HCC tissues using next-generation sequencing technology.ResultsWe found recurrent mutations in several genes such as telomerase reverse transcriptase (TERT; 65 % of the total 104 HCCs), TP53 (38 %), CTNNB1 (30 %), AXIN1 (2 %), PTEN (2 %), and CDKN2A (2 %). TERT promoter mutations were associated with older age (p = 0.005), presence of hepatitis C virus (HCV) infection (p = 0.003), and absence of hepatitis B virus (HBV) infection (p < 0.0001). In hepatitis B surface antigen (HBs Ag)-positive HCC without TERT promoter mutations, HBV integration into TERT locus was found in 47 % patients and was mutually exclusive to TERT promoter mutations. Most (89 %) HBV integrants were in the HBx region. TP53 mutations were associated with HBV infection (p = 0.0001) and absence of HCV infection (p = 0.002). CTNNB1 mutations were associated with absence of HBV infection (p = 0.010). Moreover, TERT promoter mutation was significantly associated with shorter disease-free survival (p = 0.005) and poor overall survival (p = 0.024).ConclusionsGene alterations in TERT promoter, TP53, CTNNB1, and HBV integration were closely associated with HCC development, and mutations in TERT promoter are related to poor prognosis. These results are useful for understanding the underlying mechanism of hepatocarcinogenesis, diagnosis, and predicting outcomes of patients with HCC.
9435492
TERT promoter mutations in primary liver tumors.
Next-generation sequencing has drawn the genetic landscape of hepatocellular carcinoma and several signaling pathways are altered at the DNA level in tumors: Wnt/β-catenin, cell cycle regulator, epigenetic modifier, histone methyltransferase, oxidative stress, ras/raf/map kinase and akt/mtor pathways. Hepatocarcinogenesis is a multistep process starting with the exposure to different risk factors, followed by the development of a chronic liver disease and cirrhosis precede in the vast majority of the cases the development of HCC. Several lines of evidence have underlined the pivotal role of telomere maintenance in both cirrhosis and HCC pathogenesis. TERT promoter mutations were identified as the most frequent genetic alterations in hepatocellular carcinoma with an overall frequency around 60%. Moreover, in cirrhosis, TERT promoter mutations are observed at the early steps of hepatocarcinogenesis since they are recurrently identified in low-grade and high-grade dysplastic nodules. In contrast, acquisition of genomic diversity through mutations of classical oncogenes and tumor suppressor genes (TP53, CTNNB1, ARID1A…) occurred only in progressed HCC. In normal liver, a subset of HCC can derived from the malignant transformation of hepatocellular adenoma (HCA). In HCA, CTNNB1 mutations predispose to transformation of HCA in HCC and TERT promoter mutations are required in most of the cases as a second hit for a full malignant transformation. All these findings have refined our knowledge of HCC pathogenesis and have pointed telomerase as a target for tailored therapy in the future.
34068857
Telomerase reverse transcriptase promoter mutation is an early somatic genetic alteration in the transformation of premalignant nodules in hepatocellular carcinoma on cirrhosis
Genetic determinants of the early steps of carcinogenesis on cirrhosis are still poorly understood. We aimed to evaluate the occurrence of telomerase reverse transcriptase (TERT) promoter mutations in the transformation of cirrhotic nodules into hepatocellular carcinoma (HCC). We analyzed a series of 268 liver samples, including 96 nodules developed in 58 patients with cirrhosis and 114 additional cirrhosis. All samples were screened for TERT promoter mutations, and in 31 nodules, for 10 genes recurrently mutated in HCC. Immunohistochemistry (IHC) analyses were performed for glypican 3, glutamine synthase, and heat shock protein 70. Six liver pathologists reviewed all the samples. Among The 96 nodules, 88 were firmly diagnosed as low‐grade dysplastic nodules (LGDNs; 32 cases), high‐grade dysplastic nodules (HGDNs; 16 cases), early HCC (eHCC; 23 cases), or small and progressed HCC in 17 cases. The agreement between the initial diagnosis from pathological report and the final expert consensus report was moderate for the diagnosis of benign versus malignant nodules (weighted kappa = 0.530). TERT promoter mutations were highly related to the step‐wise hepatocarcinogenesis because mutations were identified in 6% of LGDNs, 19% of HGDNs, 61% of eHCCs, and 42% of small and progressed HCC. TERT promoter mutation is the most frequent molecular alteration in eHCC given that the IHC criteria for diagnosis of malignancy were found in only 39% of the cases. TERT promoter mutation was also the earliest genetic alteration because mutations in 10 other genes were only identified in 28% of the small and progressed HCC. Conclusion: Frequency of TERT promoter mutations rapidly increases during the different steps of the transformation of premalignant lesions into HCC on cirrhosis. Consequently, somatic TERT promoter mutation is a new biomarker predictive of transformation of premalignant lesions into HCC. (Hepatology 2014;60:1982–1991)
62778996
Corrigendum: High frequency of telomerase reverse-transcriptase promoter somatic mutations in hepatocellular carcinoma and preneoplastic lesions
Somatic mutations activating telomerase reverse-trancriptase promoter were recently identified in several tumour types. Here we identify frequent similar mutations in human hepatocellular carcinomas (59%), cirrhotic preneoplastic macronodules (25%) and hepato-cellular adenomas with malignant transformation in hepatocellular carcinomas (44%). In hepatocellular tumours, telomerase reverse-transcripase-and CTNNB1-activating mutations are significantly associated. Moreover, preliminary data suggest that telomerase reverse-trancriptase promoter mutations can increase the expression of telomerase transcript. In conclusion, telomerase reverse-trancriptase promoter mutation is the earliest recurrent genetic event identified in cirrhotic preneoplastic lesions so far and is also the most frequent genetic alteration in hepatocellular carcinomas, arising from both the cirrhotic or non-cirrhotic liver.
18087614
Tumor specific mutations in TERT promoter and CTNNB1 gene in hepatitis B and hepatitis C related hepatocellular carcinoma
Recurrent somatic mutations in the promoter region of telomerase reverse transcriptase (TERT) gene and in the exon 3 of CTNNB1 gene have been recognized as common events in hepatocellular carcinoma (HCC) with variable frequencies depending on etiology and geographical region. We have analyzed TERT promoter and CTNNB1 gene mutations in 122 cases of hepatitis B (HBV) and hepatitis C (HCV) related HCCs, in 7 cases of cholangiocarcinoma (CC) and hepatocholangiocarcinoma (HCC-CC) as well as in autologous cirrhotic tissues. Overall, 50.4% and 26% of HCC as well as 14.3% and none of CC and HCC-CC were mutated in TERT promoter and in CTNNB1 exon 3, respectively. TERT and CTNNB1 mutations were found more frequently in HCV related (53.6% and 26.4%, respectively) than HBV related (41.7% and 16.7%, respectively) HCCs and coexisted in 57.6% of CTNNB1 mutated tumors. Mutations in TERT and CTNNB1 were not associated with the functional promoter polymorphism rs2853669. No mutations were detected in the 129 non-HCC cirrhotic tissues. In conclusion, mutations in TERT promoter and in CTNNB1 gene represent specific cancer signatures in the pathogenesis of viral related HCC and could be promising early biomarkers as well as targets for tailored therapies.
16405378
Telomerase reverse transcriptase promoter mutations in hepatitis B virus-associated hepatocellular carcinoma
Telomerase reverse transcriptase (TERT) promoter mutations are among the most frequent noncoding somatic mutations in multiple cancers, including hepatocellular carcinoma (HCC). The clinical and pathological implications of TERT promoter mutations in hepatitis B virus (HBV)-associated HCC have not been resolved. To investigate TERT promoter mutations, protein expression, and their clinical-pathological implications, we sequenced the TERT promoter region for hotspot mutations in HCC tissues and performed immunostaining for TERT protein expression from HBV-associated HCC in Chinese patients. Of 276 HCC tumor DNA samples sequenced, 85 (31%) carried TERT promoter mutations. TERT promoter mutations were more frequent in those with low α-fetoprotein (AFP) serum levels (p = 0.03), advanced age (p = 0.04), and in those lacking HCC family history (p = 0.02), but were not correlated with HCC stages and grades. TERT protein levels were higher in HCC (n = 28) compared to normal liver tissues (n = 8) (p =0.001), but did not differ between mutated and non-mutated tumor tissues. In conclusion, TERT promoter mutations are common somatic mutations in HCC of Han Chinese with HBV infection. Detection of TERT promoter mutations in those with low levels of AFP may aid diagnosis of HCC with atypical presentation.
16254762
TERT rs2736100 genotypes are associated with differential risk of myeloproliferative neoplasms in Swedish and Chinese male patient populations
The telomerase reverse transcriptase (TERT) gene rs2736100_C allele has recently been shown to be associated with an increased risk for myeloproliferative neoplasms (MPNs) among Caucasians. However, it is unknown if this association is present in other ethnical populations and whether rs2736100 allele frequencies mirror the incidence of MPNs in a population. Here we genotyped TERT rs2736100 variants in 126 Swedish and 101 Chinese MPN patients and their age-, sex-, and ethnically-matched healthy controls. Healthy Chinese adults had a higher frequency of the A allele and lower frequencies of the C allele compared to Swedish counterparts (57.4 vs 47.0 % for A, 42.6 vs 53.0 % for C, P = 0.006). Both Swedish and Chinese patients harbored significantly higher C allele frequency than their controls (62.7 vs 53.0 % and 57.4 vs 42.6 % for Swedish and Chinese, respectively, P = 0.004). Swedes and Chinese bearing the CC genotype had a significantly increased risk of MPN compared to AA carriers (OR = 2.47; 95 % CI: 1.33–4.57, P = 0.003, for Swedes, and OR = 3.45; 95 % CI: 1.52–7.85, P = 0.005, for Chinese). Further analyses showed that rs2736100_CC was associated with robustly enhanced risk in males only (CC vs AA, OR = 5.11; 95 % CI: 2.19–11.92, P < 0.0001). The CC-carrying MPN patients exhibited significantly higher TERT expression than patients with the AC genotype. Collectively, the rs2736100_C is a risk allele for MPNs in Swedish and Chinese males, and the lower incidence of MPNs in the Chinese population is correlated with a lower rs2736100_C risk allele frequency.
9659266
TERT promoter mutations in renal cell carcinomas and upper tract urothelial carcinomas
TERT promoter mutations are identified in many malignancies including bladder cancer (BC) and upper tract urothelial carcinoma (UTUC). In contrast, no mutations were found in renal cell carcinoma (RCC) as reported in a recent study. Because the mutant TERT promoter in urine DNA was recently tested as a marker for BC, it is important to ascertain whether these mutations are truly absent in RCCs. Here we determined TERT promoter mutations in 109 patients with RCC and 14 patients with UTUC. The mutations were found in 9/96 (9.3%) clear cell RCC (ccRCC) tumors and 1/8 (13%) chromophobe RCC tumors. Among ccRCC patients, the mutation was correlated with the advanced stages and metastasis, and higher TERT expression. Among UTUCs, the mutation was detected in tumors from 3/5 (60%) patients with renal pelvic cancer and 1/9 (11%) patients with ureter cancer. The mutation was also detected in 1 of 4 urine samples from patients with mutation+ UTUC. Collectively, TERT promoter mutations do occur in RCCs and are associated with aggressive disease. The mutation is more frequent in renal pelvic cancer. Thus, the mutant TERT promoter found in urine may come from not only BC, but also RCC or UTUC.
5874923
Telomerase reverse transcriptase locus polymorphisms and cancer risk: a field synopsis and meta-analysis.
BACKGROUND
Several recent studies have provided evidence that polymorphisms in the telomerase reverse transcriptase (TERT) gene sequence are associated with cancer development, but a comprehensive synopsis is not available. We conducted a systematic review and meta-analysis of the available molecular epidemiology data regarding the association between TERT locus polymorphisms and predisposition to cancer.


METHODS
A systematic review of the English literature was conducted by searching PubMed, Embase, Cancerlit, Google Scholar, and ISI Web of Knowledge databases for studies on associations between TERT locus polymorphisms and cancer risk. Random-effects meta-analysis was performed to pool per-allele odds ratios for TERT locus polymorphisms and risk of cancer, and between-study heterogeneity and potential bias sources (eg, publication and chasing bias) were assessed. Because the TERT locus includes the cleft lip and palate transmembrane 1-like (CLPTM1L) gene, which is in linkage disequilibrium with TERT, CLPTM1L polymorphisms were also analyzed. Cumulative evidence for polymorphisms with statistically significant associations was graded as "strong," "moderate," and "weak" according to the Venice criteria. The joint population attributable risk was calculated for polymorphisms with strong evidence of association.


RESULTS
Eighty-five studies enrolling 490 901 subjects and reporting on 494 allelic contrasts were retrieved. Data were available on 67 TERT locus polymorphisms and 24 tumor types, for a total of 221 unique combinations of polymorphisms and cancer types. Upon meta-analysis, a statistically significant association with the risk of any cancer type was found for 22 polymorphisms. Strong, moderate, and weak cumulative evidence for association with at least one tumor type was demonstrated for 11, 9, and 14 polymorphisms, respectively. For lung cancer, which was the most studied tumor type, the estimated joint population attributable risk for three polymorphisms (TERT rs2736100, intergenic rs4635969, and CLPTM1L rs402710) was 41%. Strong evidence for lack of association was identified for five polymorphisms in three tumor types.


CONCLUSIONS
To our knowledge, this is the largest collection of data for associations between TERT locus polymorphisms and cancer risk. Our findings support the hypothesis that genetic variability in this genomic region can modulate cancer susceptibility in humans.
19312520
TERT rs2736098 polymorphism and cancer risk: results of a meta-analysis.
OBJECTIVE
Several studies have demonstrated associations between the TERT rs2736098 single nucleotide polymorphisms (SNPs) and susceptibility to cancer development. However, there are conflicting results. A systematic meta-analysis was therefore performed to establish the cancer risk associated with the polymorphism.


METHODS
In this meta-analysis, a total of 6 case-control studies, including 5,567 cases and 6,191 controls, were included. Crude odds ratios with 95% confidence intervals were used to assess the strength of associations in several genetic models.


RESULTS
Our results showed no association reaching the level of statistical significance for overall risk. Interestingly, in the stratified analyses (subdivided by ethnicity), significantly increased risks were found in the Asian subgroup which indicates the TERT rs2736098 polymorphism may have controversial involvement in cancer susceptibility.


CONCLUSIONS
Overall, this meta-analysis indicates that the TERT rs2736098 polymorphism may have little involvement in cancer susceptibility.
205355914
Genome-wide association study identifies five susceptibility loci for glioma
To identify risk variants for glioma, we conducted a meta-analysis of two genome-wide association studies by genotyping 550K tagging SNPs in a total of 1,878 cases and 3,670 controls, with validation in three additional independent series totaling 2,545 cases and 2,953 controls. We identified five risk loci for glioma at 5p15.33 (rs2736100, TERT; P = 1.50 × 10−17), 8q24.21 (rs4295627, CCDC26; P = 2.34 × 10−18), 9p21.3 (rs4977756, CDKN2A-CDKN2B; P = 7.24 × 10−15), 20q13.33 (rs6010620, RTEL1; P = 2.52 × 10−12) and 11q23.3 (rs498872, PHLDB1; P = 1.07 × 10−8). These data show that common low-penetrance susceptibility alleles contribute to the risk of developing glioma and provide insight into disease causation of this primary brain tumor.
15697955
The association between the TERT rs2736100 AC genotype and reduced risk of upper tract urothelial carcinomas in a Han Chinese population
Upper tract urothelial carcinomas (UTUCs) are originated from urothelium, and consist of renal pelvic carcinomas (RPCs) and ureter carcinomas (UCs). Most UTUCs have already become invasive when diagnosed and there is thus a need to identify high-risk populations for preventive intervention. Recent evidence has accumulated supporting common single nucleotide polymorphisms (SNPs) to be associated with increased risk of various malignancies. However, little is known about susceptibility loci in relation to UTUC development. We genotyped telomerase reverse transcriptase (TERT) rs2736100 variants, the SNP associated with a risk of multiple-types of cancer, in patients with UTUC (n = 212) and evaluated the relationship between the rs2736100 and UTUC risk by comparing to 289 healthy controls. Neither AA nor CC genotypes differed significantly between cases and controls, while the AC-carriers were associated with a reduced risk of UTUC compared to the homozygous AA (OR = 0.583; 95% CI: 0.388 − 0.875; P = 0.012) or AA + CC genotypes (0.613; 95% CI: 0.428 − 0.879; P = 0.010). Further analyses showed that the AC variant conferred a lower risk for early stage UTUCs or those with a wt TERT promoter. When UTUCs were sub-grouped into UCs and RPCs, the AC genotype still predicts a significantly lower risk for UC (P = 0.045, OR = 0.597, 95% CI: 0.370 − 0.963), while at a border line significance for RPC (P = 0.055, OR = 0.597, 95% CI: 0.324 − 0.976). Collectively, the rs2736100 AC variant predicts a reduced risk to develop UTUC.
1037860
hTERT rs2736098 genetic variants and susceptibility of hepatocellular carcinoma in the Chinese population: a case-control study.
BACKGROUND
The human telomerase reverse transcriptase (hTERT) gene encodes the catalytic subunit of telomerase, which mediates pleiotropic effects, including the regulation of senescence and proliferation and plays an important role in carcinogenesis. This study attempts to clarify the genetic predisposition to hepatocellular carcinoma (HCC), focusing on the hTERT gene rs2736098 polymorphism.


METHOD
Four hundred patients with HCC and 400 non-cancer controls were genotyped to elucidate the potential association between hTERT rs2736098 polymorphism and HCC risks.


RESULTS
Compared with the controls, the patients with HCC had a lower frequency of G/G genotype (33.3% vs 44.3%, P=0.001) and a higher frequency of G/A (51.5% vs 39.5%, P=0.001). Allele genotypic frequencies in the patients differed from those of the controls (P=0.040). The data of this study rs2736098[A] allele contributed significantly to HCC risk in female patients (OR=1.78, 95% CI, 1.17-2.72, P=0.007), patients with HCV infection (OR=2.89, 95% CI, 1.08-7.70, P=0.031), non-drinker patients (OR=1.32, 95% CI, 1.06-1.65, P=0.015), and patients not affected by HBV (OR=1.77, 95% CI, 1.30-2.40, P<0.001).


CONCLUSIONS
rs2736098[A] may be an independent hereditary parameter in HCC, but some risk factors would cover up the association by more powerful hepatocarcinogenesis. These results are important guidance for further studies in detecting HCC-associated single nucleotide polymorphisms.
11410872
The germline sequence variant rs2736100_C in TERT associates with myeloproliferative neoplasms
The germline sequence variant rs2736100_C in TERT associates with myeloproliferative neoplasms
21957586
hTERT Cancer Risk Genotypes Are Associated With Telomere Length
Telomere biology is associated with cancer initiation and prognosis. Collected data suggest that blood cell telomere length (TL) can change over time, which may be related to development of common disorders, such as cardiovascular diseases and cancer. Recently, single nucleotide polymorphisms in the region of the human telomerase reverse transcriptase (hTERT) gene were associated with various malignancies, including glioma, lung and urinary bladder cancer, and telomerase RNA gene hTERC genotypes were recently linked to TL. In the present study a hypothetical association between identified genotypes in hTERT and hTERC genes and TL were investigated. We analyzed 21 polymorphisms, covering 90% of the genetic variance, in the hTERT gene, two genetic variants in hTERC, and relative TL(RTL) at average age 50 and 60 in 959 individuals with repeated blood samples. Mean RTL at age 60 was associated with four genetic variants of the hTERT gene (rs2736100, rs2853672, rs2853677, and rs2853676), two of which reported to be associated with cancer risk. Two alleles (rs12696304, rs16847897) near the hTERC gene were confirmed as also being associated with RTL at age 60. Our data suggest that hTERT and hTERC genotypes have an impact on TL of potential relevance and detectable first at higher ages, which gives us further insight to the complex regulation of TL. Genet. Epidemiol. 36:368–372, 2012. © 2012 Wiley Periodicals, Inc.
205346672
Lung cancer susceptibility locus at 5p15.33
We carried out a genome-wide association study of lung cancer (3,259 cases and 4,159 controls), followed by replication in 2,899 cases and 5,573 controls. Two uncorrelated disease markers at 5p15.33, rs402710 and rs2736100 were detected by the genome-wide data (P = 2 × 10−7 and P = 4 × 10−6) and replicated by the independent study series (P = 7 × 10−5 and P = 0.016). The susceptibility region contains two genes, TERT and CLPTM1L, suggesting that one or both may have a role in lung cancer etiology.
13964564
The TERT variant rs2736100 is associated with colorectal cancer risk
Background:Polymorphic variation at the 5p15.33 (TERT–CLPTM1L) locus is associated with the risk of many cancers but a relationship with colorectal cancer (CRC) risk has yet to be defined.Methods:We used data from six genome-wide association studies (GWAS) of CRC, linkage disequilibrium mapping and imputation, to examine the relationship between 73 single-nucleotide polymorphisms at 5p15.33 and CRC risk in detail.Results:rs2736100, which localises to intron 2 of TERT, provided the strongest evidence of an association with CRC (P=2.28 × 10−4). The association was also shown in an independent series of 10 047 CRC cases and 6918 controls (P=0.02). A meta-analysis of all seven studies (totalling 16 039 cases, 16 430 controls) provided increased evidence of association (P=2.49 × 10−5; per allele odds ratio=1.07). The association of rs2736100 on CRC risk was shown to be independent of 15 low-penetrance variants previously identified.Conclusion:The rs2736100 association demonstrates an influence of variation at 5p15.33 on CRC risk and further evidence that the 5p15.33 (TERT–CLPTM1L) locus has pleiotropic effects (reflecting generic or lineage-specific effects) on cancer risk.
21914849
Genetic variations on chromosomes 5p15 and 15q25 and bladder cancer risk: findings from the Los Angeles-Shanghai bladder case-control study.
Genome-wide association studies have associated common variations at chromosomes 5p15 and 15q25 with lung cancer risk. The 5p15 locus has also been associated with increased bladder cancer risk in a recent report. The 15q25 locus has been associated with nicotine dependence and self-reported number of cigarettes smoked per day in some studies and it was proposed that its association with lung cancer may be mediated through differences in smoking behavior. Here, we investigated the roles of variations at 5p15 (rs401681, rs402710, rs2736098 and rs2736100) and 15q25 (rs1051730 and rs8034191) in bladder cancer etiology in two case-control studies conducted separately in Los Angeles County, CA, USA (498 cases and 588 controls) and in Shanghai, China (506 cases and 530 controls). We replicated the association between the 5p15 locus and bladder cancer among non-Hispanic whites (NHW) in Los Angeles [for rs2736100, per C allele odds ratio (OR) = 1.23; 95% confidence interval (CI), 1.02-1.48; P = 0.029] and among Chinese in Shanghai (OR = 1.22; 95% CI, 1.02-1.47; P = 0.033). Both rs1051730 and rs8034191 at 15q25 were rare among Chinese. Among NHW, a significant association was found between rs8034191 and bladder cancer which persisted after adjustment for cigarette smoking status, number of cigarettes smoked per day and number of years of smoking (per C allele OR = 1.26; 95% CI, 1.04-1.54; P = 0.017). Our results support 5p15 and 15q25 as susceptibility regions for bladder cancer risk.
24549232
Multiple variants of TERT and CLPTM1L constitute risk factors for lung adenocarcinoma.
Recent studies have shown that 5p15.33 is one of the chromosomal regions that is most consistently altered in lung cancer; common variants that are located in this region have been genotyped in various populations. However, the genetic contribution of these variants to carcinogenesis is relatively unknown. A clinic-based case-control study in Shanghai was undertaken on 196 patients with lung cancer and 229 healthy individuals. TERT rs2736100 and CLPTM1L rs401681 and rs402710 were genotyped using the ABI TaqMan Allelic Discrimination assay. For rs2736100, the G variant and the GG genotype were more frequent, whereas the TT genotype was less frequent in patients with lung adenocarcinoma than in controls. The CT genotype at rs401681 was more common and the TT genotype was rare in patients, and the differences were significant between lung adenocarcinoma patients and controls. This was also true for rs402710. Moreover, the frequency of the GGCTCT haplotype was higher and the TTTTTT frequency was lower in patients, especially those with lung adenocarcinoma. Aberrant linkage disequilibrium among the three SNPs was found in patients with lung adenocarcinoma. We conclude that multiple variants at 5p15.33 contribute to susceptibility to lung adenocarcinoma.
403398
Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer
TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ∼480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases and controls. Leukocyte telomere measurements were also available for 53,724 participants. Most associations cluster into three independent peaks. The minor allele at the peak 1 SNP rs2736108 associates with longer telomeres (P = 5.8 × 10−7), lower risks for estrogen receptor (ER)-negative (P = 1.0 × 10−8) and BRCA1 mutation carrier (P = 1.1 × 10−5) breast cancers and altered promoter assay signal. The minor allele at the peak 2 SNP rs7705526 associates with longer telomeres (P = 2.3 × 10−14), higher risk of low-malignant-potential ovarian cancer (P = 1.3 × 10−15) and greater promoter activity. The minor alleles at the peak 3 SNPs rs10069690 and rs2242652 increase ER-negative (P = 1.2 × 10−12) and BRCA1 mutation carrier (P = 1.6 × 10−14) breast and invasive ovarian (P = 1.3 × 10−11) cancer risks but not via altered telomere length. The cancer risk alleles of rs2242652 and rs10069690, respectively, increase silencing and generate a truncated TERT splice variant.
8790161
TERT Polymorphism rs2736100-C Is Associated with EGFR Mutation–Positive Non–Small Cell Lung Cancer
Purpose: EGF receptor (EGFR) mutation–positive (EGFRmut+) non–small cell lung cancer (NSCLC) may be a unique orphan disease. Previous studies suggested that the telomerase reverse transcriptase (TERT) gene polymorphism is associated with demographic and clinical features strongly associated with EGFR mutations, for example, adenocarcinoma histology, never-smoking history, and female gender. We aim to test the association between TERT polymorphism and EGFRmut+ NSCLC. Experimental Design: We conducted a genetic association study in Chinese patients with NSCLC (n = 714) and healthy controls (n = 2,520), between the rs2736100 polymorphism and EGFRmut+ NSCLC. We further tested the association between the EGFR mutation status and mean leukocyte telomere length (LTL). The potential function of rs2736100 in lung epithelial cells was also explored. Results: The rs2736100-C allele was significantly associated with EGFRmut+ NSCLC [OR, 1.52; 95% confidence interval (CI), 1.28–1.80; P = 1.6 × 10−6] but not EGFRmut− NSCLC (OR = 1.07, 95% CI, 0.92–1.24, P = 0.4). While patients with NSCLC as a whole have significantly longer LTL than healthy controls (P ≤ 10−13), the EGFRmut+ patients have even longer LTL than EGFRmut− patients (P = 0.008). Meanwhile, rs2736100 was significantly associated with TERT mRNA expression in both normal and tumor lung tissues. All results remained significant after controlling for age, gender, smoking status, and histology (P < 0.05 for all tests). Moreover, the rs2736100 DNA sequence has an allele-specific affinity to nuclear proteins extracted from lung epithelial cells, which led to an altered enhancer activity of the sequence in vitro. Conclusions: Our study suggests that telomerase and telomere function may be essential for carcinogenesis of EGFRmut+ NSCLC. Further investigation for the underlying mechanism is warranted. Clin Cancer Res; 21(22); 5173–80. ©2015 AACR.
9169599
Co-occurrence of Myeloproliferative Neoplasms and Solid Tumors Is Attributed to a Synergism Between Cytoreductive Therapy and the Common TERT Polymorphism rs2736100
Background: The germline telomerase reverse transcriptase (TERT) rs2736100_C variant was identified as a susceptibility factor for a variety of solid tumors and recently for myeloproliferative neoplasms (MPN). Methods: LightCycler melting curve analysis was applied to detect risk alleles of TERT rs2736100_C and Janus kinase 2 (JAK2) rs12343867_C tagging 46/1 haplotype in 584 BCR-ABL1–negative MPN, 308 acute, and 86 chronic myeloid leukemia (AML and CML) patients and 400 healthy individuals. Results: TERT rs2736100_C showed an increased allele frequency in BCR-ABL1–negative MPN patients compared with controls (62.7%±2.8% vs. 48.8%±3.5%, P < 0.0001) regardless of molecular background or disease type, but not in CML or AML. Combined TERT and JAK2 hetero- or homozygosity conferred even higher risk for classic MPN. Common complications (thrombosis, myelofibrosis, or leukemia) were not associated with the TERT variant; however, adverse survival was noted in TERT variant carrier polycythemia vera patients. MPN patients with the TERT CC genotype had a higher probability (44.4%) to die from solid tumors compared with TERT AC/AA individuals (5.3%; P = 0.004). TERT rs2736100_C carriers had increased risk of solid tumors independently from cytoreductive treatment [3.08 (1.03–9.26), P = 0.045]. Conclusions: TERT rs2736100_C polymorphism predisposes to the development of BCR-ABL1–negative MPN with the co-occurrence of solid tumors, especially with the usage of cytoreductive treatment. Impact: The high frequency of TERT variant in the classic MPN population highlights the importance of the avoidance of long-term cytoreductive treatment in MPN patients. Cancer Epidemiol Biomarkers Prev; 25(1); 98–104. ©2015 AACR.
32477740
Sequence variants at the TERT-CLPTM1L locus associate with many cancer types
The common sequence variants that have recently been associated with cancer risk are particular to a single cancer type or at most two. Following up on our genome-wide scan of basal cell carcinoma, we found that rs401681[C] on chromosome 5p15.33 satisfied our threshold for genome-wide significance (OR = 1.25, P = 3.7 × 10−12). We tested rs401681 for association with 16 additional cancer types in over 30,000 cancer cases and 45,000 controls and found association with lung cancer (OR = 1.15, P = 7.2 × 10−8) and urinary bladder, prostate and cervix cancer (ORs = 1.07−1.31, all P < 4 × 10−4). However, rs401681[C] seems to confer protection against cutaneous melanoma (OR = 0.88, P = 8.0 × 10−4). Notably, most of these cancer types have a strong environmental component to their risk. Investigation of the region led us to rs2736098[A], which showed stronger association with some cancer types. However, neither variant could fully account for the association of the other. rs2736098 corresponds to A305A in the telomerase reverse transcriptase (TERT) protein and rs401681 is in an intron of the CLPTM1L gene.
206544787
Highly Recurrent TERT Promoter Mutations in Human Melanoma
Promoter Mutations and Cancer Cancer genome sequencing projects have highlighted the pathogenic role of recurrent mutations within the protein-coding regions of genes. Now, two studies suggest that the scope of mutations in human tumors extends to gene regulatory regions. In a study of 70 melanomas, Huang et al. (p. 957, published online 24 January) found that 71% harbored one of two specific mutations in the promoter region of TERT, the gene coding for the catalytic subunit of telomerase, the enzyme that caps chromosome ends. Independently, Horn et al. (p. 959, published online 24 January) identified a disease-segregating germline mutation in the TERT promoter in a family predisposed to melanoma and found additional TERT promoter mutations in a high percentage of sporadic melanomas and melanoma cell lines. The mutations in both studies generated new binding sites for specific transcription factors and, in reporter assays, caused an increase in transcription. A large fraction of human melanomas harbor mutations in sequences that regulate the expression of telomerase. Systematic sequencing of human cancer genomes has identified many recurrent mutations in the protein-coding regions of genes but rarely in gene regulatory regions. Here, we describe two independent mutations within the core promoter of telomerase reverse transcriptase (TERT), the gene coding for the catalytic subunit of telomerase, which collectively occur in 50 of 70 (71%) melanomas examined. These mutations generate de novo consensus binding motifs for E-twenty-six (ETS) transcription factors, and in reporter assays, the mutations increased transcriptional activity from the TERT promoter by two- to fourfold. Examination of 150 cancer cell lines derived from diverse tumor types revealed the same mutations in 24 cases (16%), with preliminary evidence of elevated frequency in bladder and hepatocellular cancer cells. Thus, somatic mutations in regulatory regions of the genome may represent an important tumorigenic mechanism.
16942691
The transcription factor GABP selectively binds and activates the mutant TERT promoter in cancer
A mutant promoter's partner in crime Telomerase is an enzyme that maintains the ends of chromosomes. TERT, the gene coding for the enzyme's catalytic subunit, is not expressed in healthy somatic cells, but its expression is reactivated in the majority of human cancers. The resultant high levels of telomerase help cancer cells survive and multiply. Recurrent mutations in the promoter region of TERT are associated with high telomerase levels in multiple cancer types. Bell et al. show that a specific transcription factor called GABP is selectively recruited to the mutant form of the TERT promoter, which activates TERT gene expression Science, this issue p. 1036 Cancer-associated mutations in the promoter of the telomerase gene allow increased activation by transcription factor binding. Reactivation of telomerase reverse transcriptase (TERT) expression enables cells to overcome replicative senescence and escape apoptosis, which are fundamental steps in the initiation of human cancer. Multiple cancer types, including up to 83% of glioblastomas (GBMs), harbor highly recurrent TERT promoter mutations of unknown function but specific to two nucleotide positions. We identified the functional consequence of these mutations in GBMs to be recruitment of the multimeric GA-binding protein (GABP) transcription factor specifically to the mutant promoter. Allelic recruitment of GABP is consistently observed across four cancer types, highlighting a shared mechanism underlying TERT reactivation. Tandem flanking native E26 transformation-specific motifs critically cooperate with these mutations to activate TERT, probably by facilitating GABP heterotetramer binding. GABP thus directly links TERT promoter mutations to aberrant expression in multiple cancers.
31779470
TERT promoter mutation as an early genetic event activating telomerase in follicular thyroid adenoma (FTA) and atypical FTA
The telomerase reverse transcriptase (TERT) promoter mutations C228T and C250T have been found in many malignancies, including in thyroid carcinomas. However, it is unclear how early these mutations occur in thyroid tumorigenesis.
2634428
TERT promoter mutations rather than methylation are the main mechanism for TERT upregulation in adult gliomas
observed TERT upregulation in some tumors without mutations in the hotspots. A small subset of tumors had neither TERT nor ATRX mutations [9]. Recently, it has been reported that DNA hypermethylation of the TERT promoter is a common finding in pediatric brain tumors and associated with TERT upregulation [2]. Hypermethylation of the TERT CpG island has been linked to increased expression levels in other cancers [2, 4, 5]. We, therefore, studied the association between TERT methylation and TERT mRNA levels to investigate the possibility that DNA methylation serves as an alternative mechanism for TERT upregulation in adult gliomas. Eighty-eight adult gliomas samples with known TERT promoter mutation status suitable for mRNA expression analysis, 43 of which had mutations, were examined in this study. TERT mRNA expression of 88 tumors including 48 primary glioblastomas that have previously been investigated was analyzed as described [1]. The methylation status of three regions within the CpG island (Regions 1–3; Fig. 1a), including the region methylated in pediatric tumors (Region 1) and the region that contains the two mutation hotspots (Region 3), was assessed by pyrosequencing of the PCR products amplified from bisulfitemodified genomic DNA. The methylation status was represented either as the mean methylation levels of all CpGs in each region or as a dichotomous variable (hypermethylated or unmethylated) at each region using the cut-off value of 15 % according to Castelo-Branco et al. [2]. More detailed information is available in Supplementary Materials and Methods. There was no significant difference in the mean methylation levels or the frequency of hypermethylated tumors in any of the regions between tumors of the different histological subtypes (astrocytic tumor, oligodendroglial tumor and glioblastoma), or between those with and without Telomere lengthening (TL) is mandatory for infinite proliferation of many cancer cells. This is generally achieved either by telomerase activation or in some cases by telomerase-independent alternative lengthening of telomeres (ALT) [3]. Recently, recurrent mutations at two hotspots termed C228T and C250T in the promoter region of TERT, a catalytic subunit of telomerase, have been reported in various types of cancers [1, 6, 7, 9, 12]. These mutations result in upregulation of TERT expression [1, 7], which is required for telomerase activation [11]. TERT promoter mutations are particularly common in adult gliomas [1, 9]. It is also known that a subset of astrocytomas harbors mutations of ATRX, which could lead to ALT [10]. We have previously shown that glioblastomas with TERT mutation had TERT mRNA upregulation [1]. We have also
6603881
The age- and shorter telomere-dependent TERT promoter mutation in follicular thyroid cell-derived carcinomas
Telomerase activation through induction of its catalytic component telomerase reverse transcriptase (TERT) expression is essential for malignant transformation. TERT promoter mutations namely C228T and C250T that stimulate TERT transcription and telomerase activation have recently been identified in many human malignancies. We thus determined these mutations and their biological and clinical implications in thyroid carcinomas in the present study. The TERT promoter was sequenced in 10 thyroid cancer cell lines and 144 tumors from 20 patients with anaplastic thyroid carcinoma (ATC), 51 with papillary thyroid carcinoma (PTC), 36 with follicular thyroid carcinoma (FTC), and 37 with medullary thyroid carcinoma (MTC). We identified C228T or C250T mutation in 6/8 of ATC cell lines, as well as in tumor tissue from 10/20, 13/51, 8/36 and 0/37 patients with ATC, PTC, FTC and MTC, respectively. In PTC patients, these mutations were exclusively present in the group with age >45 years (P<0.0001), and highly correlated shorter telomeres (P<0.0001) and distant metastasis (P=0.028). The previous radioactivity exposure did not induce the mutation. The presence of C228T or C250T was an independent predictor associated with shorter disease-related survival (DRS) in the entire cohort (P<0.0001), as well as among patients >45 years (P=0.021). ATC patients carrying the mutation survived shorter than those without mutations, although not statistically significant (P=0.129). The TERT promoter mutation was associated with overall survival (P=0.038) and DRS (P=0.058) of FTC patients. Taken together, age- and shorter telomere-dependent TERT promoter mutations occur frequently in follicular cell-derived thyroid carcinoma (ATC, PTC and FTC) but not in parafollicular cell-originated MTC, and may serve as a marker for aggressive disease and poor outcome.
25639199
Genetic variation in TERT and TERC and human leukocyte telomere length and longevity: a cross‐sectional and longitudinal analysis
Telomerase is of key importance for telomere maintenance, and variants of the genes encoding its major subunits, telomerase reverse transcriptase (TERT) and telomerase RNA component (TERC), are candidates for interindividual variation in telomere length. Recently, the two SNPs rs3772190 and rs12696304 in the TERC locus were reported to be associated with leukocyte telomere length (LTL) in two genome‐wide association studies, while one haplotype of TERT (rs2853669, rs2736098, rs33954691, and rs2853691) has been reported to be associated with both LTL and longevity in a candidate gene study. In this study, we investigated the two TERC and four TERT SNPs in middle‐aged, old, and oldest‐old Danes (58–100 years) and their association with LTL (n = 864) and longevity (n = 1069). Furthermore, data on 11 TERT tagging SNPs in 1089 oldest‐old and 736 middle‐aged Danes were investigated with respect to longevity. For all SNPs, the association with longevity was investigated using both a cross‐sectional and a longitudinal approach. Applying an additive model, we found association of LTL with the minor TERC alleles of rs3772190 (A) and rs12696304 (G), such that a shorter LTL was seen in rs3772190 A carriers (regression coefficient = −0.08, P = 0.011) and in male rs12696304 G carriers (regression coefficient = −0.13, P = 0.014). No TERT variations showed association. Moreover, the A allele of rs3772190 (TERC) was found to be associated with longevity [hazard rate (AG + AA) = 1.31, P = 0.006]. No associations with longevity were observed for the TERT SNPs or haplotypes. Our study, thus, indicates that TERC is associated with both LTL and longevity in humans.
16558402
Telomerase reverse transcriptase promoter mutations in bladder cancer: high frequency across stages, detection in urine, and lack of association with outcome.
BACKGROUND
Hotspot mutations in the promoter of the gene coding for telomerase reverse transcriptase (TERT) have been described and proposed to activate gene expression.


OBJECTIVES
To investigate TERT mutation frequency, spectrum, association with expression and clinical outcome, and potential for detection of recurrences in urine in patients with urothelial bladder cancer (UBC).


DESIGN, SETTING, AND PARTICIPANTS
A set of 111 UBCs of different stages was used to assess TERT promoter mutations by Sanger sequencing and TERT messenger RNA (mRNA) expression by reverse transcription-quantitative polymerase chain reaction. The two most frequent mutations were investigated, using a SNaPshot assay, in an independent set of 184 non-muscle-invasive and 173 muscle-invasive UBC (median follow-up: 53 mo and 21 mo, respectively). Voided urine from patients with suspicion of incident UBC (n=174), or under surveillance after diagnosis of non-muscle-invasive UBC (n=194), was tested using a SNaPshot assay.


OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS
Association of mutation status with age, sex, tobacco, stage, grade, fibroblast growth factor receptor 3 (FGFR3) mutation, progression-free survival, disease-specific survival, and overall survival.


RESULTS AND LIMITATIONS
In the two series, 78 of 111 (70%) and 283 of 357 (79%) tumors harbored TERT mutations, C228T being the most frequent substitution (83% for both series). TERT mutations were not associated with clinical or pathologic parameters, but were more frequent among FGFR3 mutant tumors (p=0.0002). There was no association between TERT mutations and mRNA expression (p=0.3). Mutations were not associated with clinical outcome. In urine, TERT mutations had 90% specificity in subjects with hematuria but no bladder tumor, and 73% in recurrence-free UBC patients. The sensitivity was 62% in incident and 42% in recurrent UBC. A limitation of the study is its retrospective nature.


CONCLUSIONS
Somatic TERT promoter mutations are an early, highly prevalent genetic event in UBC and are not associated with TERT mRNA levels or disease outcomes. A SNaPshot assay in urine may help to detect UBC recurrences.
31586630
Comprehensive mutation analysis of the TERT promoter in bladder cancer and detection of mutations in voided urine.
The link between telomere maintenance and telomerase activation has long been studied in cancer cells, but the process by which telomerase becomes activated has remained elusive. A mechanism by which some tumour cells maintain telomerase expression was uncovered by analysis of the promoter region of the telomerase reverse transcriptase (TERT) gene. Two studies reported frequent (approximately 70%) somatic mutation in the TERT promoter in melanoma [1,2] at positions 124 base pairs (bp) (G > A; C > T on the opposite strand) and 146 bp (G > A; C > T on the opposite strand) upstream from the ATG translation start codon. These mutations create consensus binding motifs for E-twenty six (ETS)/ternary complex factor (TCF) transcription factors (GGA[A/T] or CCGGAA) leading to increased TERT promoter activity. One of these studies also reported mutations at 124 bp (G > A) in three of three bladder tumour-derived cell lines [2] and two subsequent studies of relatively small numbers of bladder tumours reported mutations at the same sites. We aimed to perform comprehensive mutation analysis of the TERT core promoter in a large number of bladder cancer samples to assess clinicopathologic associations and to detect mutations in voided urine [3,4]. SNaPshot assays (Life Technologies Corp., Carlsbad, CA, USA) are sensitive, low-cost, high-throughput assays [5] suitable for detection of hotspot mutations. We designed a SNaPshot assay to detect mutations at hotspot positions 124 bp and 146 bp. This was tested on three bladder tumour–derived cell lines with 124 bp G > A mutations [2], one melanoma cell line with 146 bp G > A [2], normal human urothelial cells (NHUC), and 17 hTERT-immortalised NHUC (TERT-NHUC) cell lines. The expected mutations were detected in the tumour cell lines and not in NHUC or TERT-NHUC (Supplemental Fig. 1). Mutations were confirmed by Sanger sequencing (Supplemental Fig. 1). We then screened 44 additional cell lines and 262 tumours. Thirty-seven cell lines carried mutations at 124 bp (G > A) and three at 146 bp (G > A) (Table 1 and Supplemental Table 1). In tumours, mutations were identified at 124 bp (G > A) in 165 samples and at 146 bp (G > A) in 32 samples (Table 1 and Supplemental Table 2). In addition,
11817960
The genetic difference between Western and Chinese urothelial cell carcinomas: infrequent FGFR3 mutation in Han Chinese patients
Urothelial cell carcinoma (UCC) includes urothelial bladder carcinoma (UBC), renal pelvic carcinoma (RPC) and ureter carcinoma (UC), and its incidence varies dependent on geographical areas and tumor locations, which indicates different oncogenic mechanisms and/or different genetic susceptibility/environment exposure. The activating mutations of the fibroblast growth factor receptor 3 (FGFR3) gene and telomerase reverse transcriptase (TERT) promoter are the most frequent genetic events in UCCs. These mutations have clinical utilities in UCC initial diagnostics, prognosis, recurrence monitoring and management. However, the vast majority of the results are obtained from studies of UCC patients in Western countries, and little has been known about these in Han Chinese patients. In the present study, we screened the FGFR3 gene and TERT promoter for mutations in 116 UBC, 91 RPC and 115 UC tumors from Han Chinese patients by using Sanger Sequencing. TERT promoter mutations occurred at a high frequency in these UCC patients, comparable with that seen in Western patients, however, the FGFR3 mutation was surprisingly lower, only 9.4% for UBCs, 8.8% for RPCs and 2.6% for UCs, respectively. Taken together, the FGFR3 gene is an infrequent target in the pathogenesis of Han Chinese UCCs, and its mutation detection and targeted therapy have limited clinical utility in these patients. Our results underscore the need for extensive characterization of cancer genomes from diverse patient populations, thereby contributing to precision medicine for cancer treatment and prevention.
39492059
TERT promoter mutations and TERT mRNA but not FGFR3 mutations are urinary biomarkers in Han Chinese patients with urothelial bladder cancer.
The TERT promoter and FGFR3 gene mutations are two of the most common genetic events in urothelial bladder cancer (UBC), and these mutation assays in patient urine have been shown to be promising biomarkers for UBC diagnosis and surveillance. These results were obtained mainly from studies of patients with UBC in Western countries, and little is known about such information in Han Chinese patients with UBC. In the present study, we addressed this issue by analyzing tumors from 182 Han Chinese patients with UBC and urine samples from 102 patients for mutations in the TERT promoter and FGFR3 and TERT mRNA expression in tumors and/or urine. TERT promoter and FGFR3 mutations were identified in 87 of 182 (47.8%) and 7 of 102 (6.7%) UBC cases, respectively. In 46 urine samples from patients with TERT promoter mutation-carrying tumors, the mutant promoter was detected in 24 (52%) prior to operation and disappeared in most examined urine samples (80%) taken 1 week after operation. TERT mRNA was detected in urine derived from 46 of 49 patients (94%) that was analyzed before operation independently of the presence of TERT promoter mutations. Collectively, FGFR3 mutations occur at a very low rate in Han Chinese UBC and cannot serve as diagnostic markers for Chinese patients. Han Chinese patients with UBC have relatively low TERT promoter mutation frequency compared with patients in Western countries, and simultaneous detection of both mutant TERT promoter and TERT mRNA improves sensitivity and specificity of urine-based diagnosis.
23194930
TERT Promoter Mutations in Familial and Sporadic Melanoma
Promoter Mutations and Cancer Cancer genome sequencing projects have highlighted the pathogenic role of recurrent mutations within the protein-coding regions of genes. Now, two studies suggest that the scope of mutations in human tumors extends to gene regulatory regions. In a study of 70 melanomas, Huang et al. (p. 957, published online 24 January) found that 71% harbored one of two specific mutations in the promoter region of TERT, the gene coding for the catalytic subunit of telomerase, the enzyme that caps chromosome ends. Independently, Horn et al. (p. 959, published online 24 January) identified a disease-segregating germline mutation in the TERT promoter in a family predisposed to melanoma and found additional TERT promoter mutations in a high percentage of sporadic melanomas and melanoma cell lines. The mutations in both studies generated new binding sites for specific transcription factors and, in reporter assays, caused an increase in transcription. A large fraction of human melanomas harbor mutations in sequences that regulate the expression of telomerase. Cutaneous melanoma occurs in both familial and sporadic forms. We investigated a melanoma-prone family through linkage analysis and high-throughput sequencing and identified a disease-segregating germline mutation in the promoter of the telomerase reverse transcriptase (TERT) gene, which encodes the catalytic subunit of telomerase. The mutation creates a new binding motif for Ets transcription factors and ternary complex factors (TCFs) near the transcription start and, in reporter gene assays, caused up to twofold increase in transcription. We then screened the TERT promoter in sporadic melanoma and observed recurrent ultraviolet signature somatic mutations in 125 of 168 (74%) of human cell lines derived from metastatic melanomas, 45 of 53 corresponding metastatic tumor tissues (85%), and 25 of 77 (33%) primary melanomas. The majority of those mutations occurred at two positions in the TERT promoter and also generated binding motifs for Ets/TCF transcription factors.
21391374
hTERT genetic variation in depression.
BACKGROUND
Telomeres are protective DNA-protein complexes forming the chromosome ends. TL differs between tissues. Shorter telomere length (TL) in blood leukocytes (LTL) has been associated with major depression, and with previous exposure to childhood adversity. TL studies on non-invasively sampled salivary DNA are less common. Telomerase, with its catalytic subunit hTERT, counteracts telomere shortening. Reduced telomerase activity associates with depression-like behavior in mice. Recently, the minor allele of the hTERT polymorphism rs2736100 was associated with shorter LTL among primarily healthy individuals. We hypothesized that (i) TL in saliva DNA is shortened in adults with a history of depression, and that (ii) rs2736100 is implicated in depression and depressive episodes in bipolar disorder type 1 (BD1).


METHODS
Individuals with a history of depression and those without (controls) were identified using self-reported questionnaires from a well-characterized population-based cohort. Clinical BD1 patients were diagnosed by specialized psychiatrists. Saliva TL was measured in age-matched depressed individuals and controls (n=662) using qRT-PCR. rs2736100 was genotyped in 436 depressed individuals, 1590 controls, and 368 BD1 patients.


RESULTS
Saliva TL was shorter in depressed individuals compared to controls. The rs2736100 minor allele was associated with depression among those without experience of childhood adversity, and with number of depressive episodes in BD1 patients responding well to lithium.


LIMITATION
Psychopathological symptoms were recorded at two time points only, 3 and 6 years prior to DNA sampling.


CONCLUSIONS
This is the first report on hTERT genetic variation in mood disorder. It proposes that genetic variation in hTERT may influence the susceptibility to depression.