A 25-year-old man presents 1 week after discovering that his left testicle is twice the normal size. Physical examination reveals a nontender, testicular mass that cannot be transilluminated. Serum levels of alpha-fetoprotein and human chorionic gonadotropin are normal. A hemiorchiectomy is performed, and histologic examination of the surgical specimen shows the cells grow inalveolar or tubular patterns, the neoplastic cells have an epithelial appearance,exhibit hyperchromatic nuclei with prominent nucleoli.. Compared to normal adult somatic cells, this germ cell neoplasm would most likely show high levels of expression of which of the following proteins?
The given histological examination is indicative of embryonal carcinoma. The tumor cells are large and have basophilic cytoplasm, indistinct cell borders, large nuclei, and prominent nucleoli.The neoplastic cells may be arrayed in undifferentiated, solid sheets or may form primitive glandular pattern. Somatic cells do not normally express telomerase,(enzyme that adds repetitive sequences to maintain the length of the telomere) Thus, with each round of somatic cell replication, the telomere shoens. The length of telomeres may act as a "molecular clock" and govern the lifespan of replicating cells. Cancer cells and embryonic cells express high levels of telomerase Embryonal carcinoma with papillary growth -The other choices are not involved in malignant transformation.
Desmin
Dystrophin
Cytochrome c
Telomerase
General Concepts