Preliminary Screening Of Genes And Protein About Radiosensitivity Of Colorectal Cancer

Objective: to screen the genes and proteins about radiosensitivity of human colorectal cancer by gene chip and protemics.Methods: 1.Part of gene: Two human colorectal cancer cell lines LOVO and SW480 were cultivated and the total RNA was extracted from at least 1×107 cells. Then, gaining the gene expression profiling by HG- U133 Plus 2.0 Array, analysising the difference and screening the genes expressed differently. 2. Part of protein: the cells cultivated by the same way received radiation of different doses with 0 Gy,2 Gy,4 Gy,6Gy X-ray. Then , detected the protein spectra of the two cell lines by means of SELDI-TOF protein chip at 24th hours after radiation. Analysising the proteins expressed differently using the software of protein chip 3.2.0, and compare the differenced expression in each other by the database of Swiss-Prot.Consequence:1,There are 16882 genes expressed in LOVO cell and 17114 genes expressed in SW480 cell through gene expression profiling.2,The genes with 2-fold expressed differentially include 908 genes up-regulated and 1312 genes down-regulated. Same genes, such as Fas and NFkB which is up-regulated and Caspas6 and RAD21 which is down-regulated have been proved to relate to radiosensitivity based on research.3,The genes with high expression level including CEACAM5,THBS1,SERPINE2,ARL7,HPGD in LOVO cell may relate to the radiosensitivity ; and the genes with high expression level including SCD,NQ01,LYZ,KRT20,ATP1B1 in SW480 cell may relate to the radioresistance of human colorectal cancer.4,There are 5 protein peaks with different expression leve comparing two protein spectras, and the average m/z are 3366.87,4743.52,6077.43,7259.53,9155.45.