expression of microrna221 and il17 in papillary thyroid carcinoma and correlation with clinicopathologic features objective to study the expression of microrna221mir221 and il17 in papillary thyroid carcinoma ptc and their roles in the carcinogenesis of ptc methods realtime rtpcr western blot and immunohistochemistry ihc were used to detect the expression of mir221 and il17 in 40 cases of ptc 20 adjacent normal thyroid tissues and 20 cases of nodular goiter and the correlation with clinicopathologic features was analyzed results 1the expression level of mir221 was significantly higher in ptc compared with nodular goiter and adjacent normal thyroid tissue p005 the expression of mir221 was related to tnm staging capsular invasion and lymph node metastasis p005 ihc assay showed positive expression of il17 in ptc but not in nodular goiter and adjacent normal thyroid tissue il17 expression was related to tnm staging capsular invasion and lymph node metastasis but not to patients age sex tumor size tumor spread and vascular invasion3 expression analysis revealed a significant correlation between the mir221 and il17 expression r0524 p0001 conclusions the expressions of mir221 and il17 are significantly higher and positively correlated in ptc suggesting that mir221 may regulate il17 expression by interacting with a variety of cytokines and inflammatory cells to participate in the development of ptc mir221 may be a potential novel prognostic indicator and therapeutic target for ptc