Cyclin-dependent kinase 7 is a potential therapeutic target in papillary thyroid carcinoma

Abstract

Given the pathological incidence of metastases or radioiodine-refractory papillary thyroid carcinoma (PTC) is increasing worldwide, patients have little alternatives when choosing effective drugs. Therefore, it is necessary to develop new therapeutic targets for PTC treatment. CDK7 is a member of the cyclindependent protein kinase (CDK) family, which plays an important role in various types of cancers. In this study, we found CDK7 were upregulated in PTC cell lines compared to normal thyroid cells using qRT-PCR and Western blot. Furthermore, using cell counting kit-8 (CCK-8) assay and 5-ethynyl-2-deoxyuridine (EdU) assay, we discovered cell growth ratio was positively correlated to the expression level of CDK7. Cell cycle analysis showed that the cells with higher CDK7 expression levels were prone to be in S phase. More importantly, we tested the inhibitory effects of BS-181 on CDK7 both in vitro and in vivo. Results obtained from this study indicated that BS-181 not only suppressed the cell proliferation in vitro, but also inhibited the tumor growth in nude mouse without changing mRNA and protein levels of CDK7. In conclusion, our study might provide a novel potential target for PTC therapy.