Inhibition Of HnRNPA2B1Gene Expression By RNA Interference Affected The Proliferation，Cell Cycle And Apoptosis In Breast Cancer Cell Lines MCF-7and MDA-MB-231

ObjectiveHnRNPA2B1belongs to the A/B subfamily of ubiquitously expressedheterogeneous nuclear ribonucleoproteins (hnRNPs). HnRNPA2B1overexpression has been described in many cancers, including breast,pancreas, liver and gastrointestinal cell lines. And it has been reported thathnRNPA2B1plays a key role in the regulation of fundamental biologyespecially related to cancer. Results of silencing hnRNP A2B1have beenreported in a number of human cancers but not in breast cancer.MethodsTo shed light on this issue, we used silencing tools in breast cancer cellsline MCF-7and MDA-MB-231to study the function of hnRNPA2B1. Weused hnRNPA2B1/shRNAs to knock-out hnRNPA2/B1gene expression inthe human breast cancer cell lines MCF-7and MDA-MB-231. Then weperformed real-time quantitative PCR and western blot to detect expressionlevels of hnRNPA2B1mRNA and protein in stable transfectants cell lines and negative control cells. Cell proliferation in24h、48h and72h wasexamined by a MTT assay. Cell cycle distribution and apoptosis weredetected by Flow Cytometry (FCM) analysis.ResultsWe discovered that using the RNAi technology viahnRNPA2B1/shRNAs, the expression level of hnRNPA2B1gene andprotein in breast cancer cells line MCF-7and MDA-MB-231were bothdown-regulate. Inhibition of hnRNPA2B1expression in MDA-MB-231and MCF-7cells by RNAi significantly affected cell proliferation in72h,increased apoptosis, and arrested cells in S phase.ConclusionThe conclusion of our research is that hnRNPA2B1may play a criticalrole in cell proliferation, cell cycle distribution and apoptosis of humanmalignant breast cancer cells.