Experimental Study On Expression Of PEgr-p16 And The Role Of Anti-tumor Induced By Ionizing Radiation

ExPerimental study on exPression of PEgr-P16 and the role of anti-tumor indueed by ionizing radiation In this study, aeeording to the meehanism that ionizing radiation ean aetivateearly growth resPonse-1(Egr-l)gene Promoter,whieh induees the exPression ofdownstream genes and anti-tumor effeet of a tumor suPPressor gene P16,thus,areeombinant Plasmid whieh eontaining human suPPressor gene P16 andradio-sensitive Promoter(Egr-l)was eonstrueted. It has been demonstrated that 6oeo-rays irradiation ean enhanee theexPression of P16 in HeLa and SMMC-7721 eells whieh were transfeeted byrecombined Plasmids PEgr-P16 in vitro.It was higher than that in HeLa andSMMC-772 1 eells whieh were not transfeeted.The researeh also demonstrated thatradiation ean deerease the exPression of CDK4 and CyelinD 1 Protein level anddeerease the exPression ofe-mye gene transeriPtional level in Hel,a eells andSMMC-772 1 eells whieh were transfeeted by reeombined Plasmids PEgr-P16.Theinerease or deerease of exPression of P16 and eorrelative downstream genesdePends on Egr-1 Promoter that aetivated by ionizing radiation.Theabove-meniioned roles and radiation effeets indueed GZ/M arrest and inhibited eellgrowth in HeLa and SMMC-7721 eells finally. This researeh has an imPortant and Praetieal signifieanee for investigating newtheraPy method that inerease radiotherapeutie effeets on malignant tumor.