The Relationship And Mechanism Between PFIA6and Development Of Cancer

Objective: Cancer is a common diease, the incidence and mortality of cancer on aglobal scale is quite significant, posing a serious threat to human health with theimprovement of living standard. Cells of local tissues lose control on their growthregulation at the level of genes leading to clonal hyperplasia and insufficient apopstosis.The result is neoformation with the effects of various tumorigenic factors. Proteins playan important part in biological function. The complex interaction among genes orproteins, intracellular activity, as well as the environmental changes will impact theexpression of gene and post-translational processing of protein. With the completion ofthe human genome draft sequence, research on tumors has widened from gene level toprotein level. Finding new proteins related to the development of tumor for thediagnosis and treatment of cancer is very important.PDIA6is a lung squamous cancer related protein screened by high throughputexperiments. This experiment examined the expression of this protein in clinical lungsquamous cancer tissues to verify the different expression of the protein between lungsquamous cancer tissues and adjacent tissues. The relationship and the mechanismbetween PDIA6and cancer were studied in Hela cells. The PDIA6recombinant plasmidwas transfected into lung squamous cancer cell line NCI-NCI-H520to get the stabletransfectde cell lines in attempt to find annother possible entry point for tumor diagnosisand treatment.Methods:1. The expression of PDIA6protein in lung cancer and adjacent tissueswas tested by Western blotting analyses.2. pCMV-sport6-PDIA6plasmid or its vectorwas transiently transfected into Hela cell, respectively. MTT assay and colonyformation assay were used to detect the proliferation ability of cancer cells.Dual-luciferase report gene detection system was used to detect the pathway related tocancer being activated by PDIA6. And then the expression of protein related to cancer was tested by Western blotting.3. pEGFP-N1-PDIA6plasmid or its vector wastransfected into NCI-H520cells, respectively. the stable transfectde cell lines was usedto examine the expression of protein related to cancer was tested by Western blotting.Results:1. The results of Western blotting assay showed that the expression ofPDIA6protein in lung cancer tissues was significantly higher than that of adjacenttissues (p﹤0.05).2. MTT assay and colony formation assay showed PDIA6couldpromote the proliferation of Hela cells. The results of dual-luciferase report genedetection system showed that PDIA6could activate Wnt pathway. The expression ofPDIA6, CCND1, β-catenin in Hela cells transfected with pCMV-sport6-PDIA6plasmidwas significantly higher than that of the cells transfected with pCMV-sport6plasmid (p﹤0.05). The expression of Bax, Caspase3in Hela cells transfected withpCMV-sport6-PDIA6plasmid was significantly lower than that of the cells transfectedwith pCMV-sport6plasmid (p＜0.05).3. For the NCI-H520cell line with stableoverexpression of PDIA6, the expression of CCND1and β-catenin expression wassignificantly higher than the control (p＜0.05). The expression of Bax and Caspase3was significantly lower than the control (p＜0.05).Conclusions:1. PDIA6may promote the proliferation of Hela cells by activatingthe Wnt pathway.2.The overexpression of PDIA6may inhibit apoptosis by thedown-regulation of Bax and Caspase3.3. PDIA6protein may be a lung squamouscancer related protein. Its overexpression can lead to the up-regulated expression ofCCND1, β-catenin and the down-regulated expression of Bax and Caspase3.