Effect of miRNA-144-3p on drug resistance sensitivity of thyroid cancer cells by targeting and regulating PAX8 gene / 中国医师杂志

ABSTRACT

Objective:To investigate the effect of microRNA-144-3p (miRNA-144-3p) on drug resistance sensitivity of thyroid cancer cells by targeting and regulating paired box gene 8 (PAX8).Methods:Human thyroid cancer cell line FTC-133 was cultured in vitro and selected to construct the cisplatin-resistant cell stains. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the relative expression of miRNA-144-3p in FTC-133 cells and cisplatin-resistant FTC-133 cells. The cisplatin-resistant FTC-133 cells were divided into group A, group B, and group C. Group A received no treatment, group B was transfected with empty plasmids, and group C was transfected with pCDNA3.1+ miRNA-144-3p plasmids. RT-PCR was used to detect the relative expression levels of miRNA-144-3p and PAX8 in each group, and methyl thiazolyl tetrazolium (MTT) method was used to detect the half inhibitory concentration (IC 50) value of cisplatin on cells in each group, proliferation rate in each group was detected by cell counting kit-8 (CCK-8) method, and apoptosis rate in each group was detected by flow cytometry. Results:The relative expression level of miRNA-144-3p in cisplatin-resistant FTC-133 cells was significantly higher than that of FTC-133 cells [(0.93±0.24) vs (0.26±0.04), P<0.05]; The IC 50 value, proliferation rate, apoptosis rate and relative expression levels of miRNA-144-3p and PAX8 in cisplatin-resistant FTC-133 cells in group B were not significantly different from those in group A ( P>0.05). The IC 50 value, proliferation rate and relative expression of miRNA-144-3p of cisplatin resistant FTC-133 cells in group C were significantly higher than those in group B ( P<0.05), and apoptosis rate and relative expression of PAX8 were significantly lower than those in group B ( P<0.05). Conclusions:Overexpression of miRNA-144-3p may increase cisplatin resistance of thyroid cancer cells by up-regulating PAX8 gene expression, thus promoting the proliferation of thyroid cancer cells and inhibiting their apoptosis.