Study Of Fused Polypeptide TAT-DV3-BH3 Inducing Apoptosis In Colon Cancer Cells And Of Screening For Phosphorylation Cyclins

Malignant tumors have become the No.1 killer to human health.Tumor biotherapy has been the forth mode of tumor therapy following operation, chemotherapy and radiotherapy.Previous studies had indicated that polypeptide drug had anti-tumor effects on cancer cells.Our laboratory had investigated the anti-tumor function of PUMA transferred into cancer cell by adenoviral vectors.In the present study we designed a fused polypeptide with the BH3 domain of PUMA as the core functional domain,facilitated by TAT and DV3 domain,in which TAT could transport large(＞10 kDa) cargo across cell membrane,whereas DV3 is the ligand of CXCR4.Our research results indicated that the polypeptide could in vitro inhibit growth of various cancer cells,including colon cancer,lung adenocarcinoma,and breast carcinoma,but not immortalized human embryonic kidney cells(HEK293).The fused polypeptide could permeate the tumor cells quickly and mainly locate in cytoplasm,but not in nuclear.The fused polypeptide inhibited the proliferation of cells by inducing it apoptosis and the cells showed morphological apoptotic characteristics.The results of mechanism study revealed that the fused polypeptide induced tumor cell apoptosis via the mitochondria pathway.In vivo experiments demonstrated that the fused peptide is capable of inhibiting tumor growth in nude mice model by intratumoral injection,without noticeable side effects on mice growth.Moreover,when the fused peptide is administered by tail vein,the polypeptide targeted the established tumor mass.No other organs were involved fused polypeptide concentration except the organs for drug metabolism,liver and kidney.In shorts,the designed fused polypeptide displayed significant anti-tumor effects both in vitro and in vivo.The fused polypeptide can specifically target to tumor tissue in vivo.This study provide solid basis for the fused peptide to be used in future investigation and potential clinical application.Meantime,this study explored phosphoprotein about cyclins and chose two colon cancer cells for experiment.The onset time of P53 was found when the cells were treated by UV.Four samples were gained for mass spectrographic analyzing after they were isolated,purified and concentrated.