The Function Of C2orf40in Breast Cancer And Related Mechanism

BackgroundBreast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females, accounting for23%of the total cancer cases and14%of the cancer deaths. However, the involved genetic and epigenetic mechanisms in tumorigenesis and progression ofbreast cancer havenot been fully revealed, resulting in the difficulties inprevention and therapy. The inactivation and dysfunction of tumor suppressor genes is one of the major pathological factorsin the development of breast cancer. Our previous study observed that expression of the candidate tumor suppressor gene C2orf40is correlated with the prognosis of breast cancer patients and the inactivation of C2orf40is related with the C2orf40promoter hypermethylation, but the effect and mechanism of C2orf40in breast cancer progression are not clear. Therefore, it is important to further explore the relation between function of tumor suppressor gene C2orf40and development of the breast cancer, and to reveal the precise mechanisms of breast cancer development. That is important for us to study the prognosis and treatment of breast cancer.Objective1To establish human breast cancer cell lines stably expressing C2orf40and silencingC2orf40toprovide useful cell models for further research.2To study the influence of C2orf40gene on the proliferation、migration、 invasion of breast cancer cells.3To explore the mechanism involved in the biological effectsof C2orf40in breast cancer. Methods1The eukaryotic expression vectors pBabe-puro-C2orf40was used to transfect the human breast cancer cell lines MDA-MB-231and BT549by retroviral transduction, two C2orf40shRNA vectors pSuper-puro-sh.C2orf40.A pSuper-puro-sh.C2orf40.Bwere used to transfect MDA-MB-468to silence C2orf40expression; Expression levelsof C2orf40mRNA in these transduced breast cancer cell lines was determined by reverse transcription polymerase chain reaction (RT-PCR).2The proliferative ability of breast cancer cells was determined by MTT and colony formation assays; wound scratch, Transwell chamber assays were used to detect the ability of cell migration and invasion.3The cell cycle pattern was assayed by flowcytometry,expression of UBE2C in transduced breast cancer cell lines was detected by qRT-PCR and Western Blot.Results1C2orf40was stably expressedin transduced MDA-MB-231and BT549cells; C2orf40expression was stably reduced in transduced MDA-MB-468cells.2These cells with forced expression of C2orf40formed significantly fewer and smaller colonies and exhibited inhibited cell proliferation, cell migration and invasion; silenced C2orf40expression in breast cancer cells enhanced the ability of cell proliferation^colony formation migration and invasion.3The transfection of C2orf40gene in breast cancer cells blocked cell cycle progression at G2/M phase;overexpression of C2orf40reduced expression of UBE2C.Conclusion1C2orf40was confirmed to inhibit the proliferation^migration and invasion of human breast cancer cells.2Overexpression of C2orf40in breast cancer cells inhibited cell proliferation by blocking cell cycle progression at G2/M,which might mediated by inhibiting the expression of UBE2C, a major component of APC complex.