Abstract: Objective To investigate the effect and underlying mechanism of zinc finger CCHC-type containing 12 (ZCCHC12) in regulating thyroid cancer cell proliferation and apoptosis. Methods The protein expression of ZCCHC12 in cancer tissues and non-tumor normal tissue in 30 thyroid cancer patients, and expression of cleaved caspase-3, caspase-9, BMP-2, p-smad1, smad 1, ID3 in thyroid cancer cells were measured by western blot. ZCCHC12 overexpression vector (pcDNA3.1-ZCCHC12) or inhibition vector (ZCCHC12 siRNA) was transfected into thyroid cancer cell line CGTH W-3 or FTC-133, respectively. Cell proliferation was measured by MTT method. Cell apoptosis was detected by flow cytometry. Results The protein expression of ZCCHC12 was significantly increased in thyroid cancer tissue compared with non-tumor normal tissue (P<0.05). ZCCHC12 overexpression significantly elevated cell proliferation, decreased cell apoptosis, inhibited expression of apoptosis-related protein cleaved caspase-3 and caspase-9, and increased protein expression of BMP-2, p- smad 1 and ID3 in CGTH W-3 and FTC-133 (P<0.05). The effect of ZCCHC12 inhibition vector was opposite from over-expression vector. Conclusions ZCCHC12 elevates the proliferation and inhibits the apoptosis of CGTH W-3 and FTC-133 cells through regulating BMPs/smad pathway.

Key words: Thyroid cancer, CGTH W-3, FTC-133, ZCCHC12, BMPs/smad