Role Of P38Signaling Pathway In Gastrin-induced Cell Proliferation And Apoptosis Of Large Intestinal Cancer And Regulation Mechanisms Study

Objective:To obseve the p38MAPK gene silence by p38MAPK-siRNA and explore therelationship between the cells proliferation and apoptosis of large intestinal cancerinduced by gastrin and signal transduction pathway of P38-MAPK. Preliminarydiscussion on whether gastrin promote the proliferation of colorectal cancercells,through the influence the expression p38MAPK. To defined the molecularmechanism of gastin promote the growth of colorectal cancer cells.Methods: RTQ-PCR detected the expression of gastrin receptor (CCK-2R) mRNA inSW480cells. SW480cells were incubated in the different medium according ondifferent requirement. MTT assay investigated the apoptosis change of SW480cells anddetermined the optimal concertration of pentagastrin to intervene the cell apoptosis. Cellexperiment is divided into four groups: Group A: the blank control group; group；B:the negative shRNA group; Group C:Gastrin group; Group D: p38MAPK-shRNAinterference+gastrin group. Group B change the medium with1%FBS after4-6hours,then cultured24hours. Group D change the medium with pentagastrin after4-6hours,then cultured24hours. Cells proliferation of SW480were analyzed with flowcytometry at the optimal concertration of drugs. The expression of P38protein levelswere detected by Western blot.Results qRT-PCR test results showed that CCK-2R mRNA was expressed of in theSW480cells.Pentagastrin inhibited SW480cells apoptosis in a dose dependent manner （6.25-200mg/L）, and optimal dose is25.00mg/L （P<0.05）. We got the maximumtransfection efficiency between40%-50%, by detecting green fluorescence.P38MAPK-shRNA interference+gastrin group proliferation index(26.47±1.24)%,significantly higher than the control group(24.34±0.67)%and thenegative shRNA interference group (24.18±1.43)%(P<0.05), gastrin group cellproliferation index was (26.39±1.15)%, significantly higher than blank control groupand the negative shRNA interference group (P<0.05). There was no significantdifference between Blank control group cell proliferation index and the negative shRNAinterference group (P>0.05). There was no significant difference between gastrin groupand p38MAPK-shRNA interference+gastrin group differences too(P>0.05). Theexpression level of p38protein between the four groups was differnt（P<0.01）.Theexpression level of p38in the gastrin group and p38MAPK-shRNA interference+gastrin group was lower than that in the control group(P<0.01), also lower than thenegative shRNA interference group (P<0.01).The p38expression level of the negativeshRNA interference group was no difference with the blank control group(P<0.05).There was also no significant difference between gastrin group and thep38MAPK-shRNA interference+gastrin group(P>0.05).Conclusion:Gastrin can inhibit the human colon cancer cell line SW480apoptosis andenhance their proliferation, the expression of p38MAPK was inhibited.P38MAPK-shRNA could effectively inhibit the expression of p38MAPK and promotethe cells proliferation of colorectal cancer. Gastrin perhaps regulates the cellsproliferation of colorectal cancer by signal transduction pathway of P38-MAPK ways.