Functional Study Of MiR-296 In Prostate Cancer Cells

Most of the primary prostate cancers are androgen-dependent. Androgen dependent LNCaP cells and androgen independent CL-1 cells are a pair of cell lines commonly used in the study of androgen regulation. We found that miR-296 is up-regulated by 2.73 folds in the microarray analysis of LNCaP cells simulated with the androgen analogue R1881 as compared with untreated LNCaP cells,quantitative real-time PCR revealed that miR-296 expression level is higher in CL-1 cells than that in LNCaP cells.The biological function of miR-296 in prostate cancer cells was studied by transfecting sense and antisense miR-296 containing 2'-OMe modifications at every base. Inhibition of miR-296 could increase the apoptosis rate of CL-1 cells and decrease the growth rate of androgen starved LNCaP cells. These indicate that miR-296 may be functional in androgen regulation network in prostate cancer cells.In order to study the function of miR-296 in prostate cancer cells, MPSS was employed to compare the change of genes'expression in the LNCaP cells transfected with sense and antisense miR-296. The results showed that 333 genes were up-regulated by more than 2 folds in the LNCaP cells transfected with antisense miR-296. By comparing with computer predicted miR-296 targets, 15 of them were selected and validated using semi-quantitative reverse transcription PCR. BTBD14B gene was found to be expressed higher in LNCaP cells transfected with antisense miR-296 as compared with cells transfected with sense miR-296. Moreover, sequence blast revealed that two repeated conservative sequences in BTBD14B mRNA are complementary to the sequence of miR-296.This study proved that miR-296 plays important roles in modulating growth and apoptosis of prostate cancer cells through regulation of downstream target gene BTBD14B.