PRSS1 Regulates Gastric Cancer Cell Proliferation Through The JAK2/STAT3 Pathway

[Objective] Gastric cancer is one of the most common malignant tumors in China,and its morbidity and mortality rank in the forefront of all malignant tumors.In the earlier stage,we screened the differentially expressed protein serine proteinase-1(PRSS1)associated with gastric cancer by proteomics and other methods,and confirmed that it was highly expressed in gastric cancer tissues.The purpose of this study was to observe the effects of interference with PRSS1 expression on the proliferation of gastric cancer cells and explore its mechanism.[Methods] 1.Gastric cancer cell lines MGC803 and BGC823 with high expression of PRSS1 were detected by Western blot.2.MGC803 and BGC823 cells were infected by lentiviral fluorescence interference vector HU6-MCS-Ubiquitin-mcherry ires-neomycin.After screening,BGC823 cells and MGC803 cells with stable and low expression of PRSS1 were established,and the expression of PRSS1 was detected by Western blot.3.The CCK8 method and plate clone formation method were used to observe the effect of low PRSS1 expression on the proliferation of gastric cancer cells.Western blot was used to detect the expression of proliferation-related protein PCNA after low expression of PRSS1.4.The effects of interference with PRSS1 expression on migration and invasion of gastric cancer cells were observed by cell scratch assay and Transwell migration and invasion assay,and the expression of EMT-related proteins were detected.5.Western blot was used to detect the expression and phosphorylation of JAK2/STAT3 pathway related proteins after the low expression of PRSS1,and to analyze the role of JAK2/STAT3 pathway in the growth,proliferation,migration and invasion of gastric cancer cells.6.Mi R-146a-5p mimics,miR-146a-5p inhibitor and control were transfected instantaneously into BGC823 and MGC803 cells,and the expression of miR-146a-5p was detected by q RT-PCR.The effects of miR-146a-5p expression on PRSS1 expression,EMT-related proteins and JAK2/STAT3 pathway were detected by Western blot.[Results] 1.Western blot results showed that PRSS1 was highly expressed in gastric cancer SGC7901,BGC823 and MGC803 cells,and the highest expression was found in BGC823 and MGC803 cells.2.The stable low expression BGC823 and MGC803 cell lines were constructed,and the Western blot results showed that SIPRSS1-3 had the best interference effect;3.CCK8 assay and clone formation assay results showed that the proliferation ability of BGC823 and MGC803 cells was decreased after low expression of PRSS1 compared with empty vector group and non-transfected group(P<0.05).Western blot results showed that the expression level of proliferation-related protein PCNA in BGC823 and MGC803 cells was significantly down-regulated after silencing PRSS1(P<0.05).4.The results of cell scratch assay showed that the migration distance of BGC823 and MGC803 cells with low PRSS1 expression was lower than that of empty vector group and untransfected group(P<0.05);Transwell migration and invasion assay showed that the number of migration of BGC823 and MGC803 cells after low expression of PRSS1 was significantly lower than that of empty vector group and non-transfected group(P<0.05);the expression of Vimentin and N-cadherin decreased after the low expression of PRSS1,while the expression of E-cadherin increased(P<0.05).5.Western blot results showed that the expression of p-JAK2 and p-STAT3 decreased after the low expression of PRSS1(P<0.05),while the expression of JAK2 and STAT3 did not change significantly(P>0.05).6.Western blot results showed that miR-146a-5P mimic could down-regulate PRSS1,and the expression of Vimentin,N-cadherin,p-JAK2 and p-STAT3 were decreased,while the expression of E-cadherin was increased(P<0.05).In addition,miR-146a-5p inhibitor could up-regulate PRSS1,increase the expression of Vimentin,N-cadherin,p-JAK2 and p-STAT3 protein,and decrease the expression of E-cadherin protein(P<0.05).The expression of JAK2 and STAT3 did not change significantly(P>0.05).[Conclusions] 1.The proliferation,migration and invasion ability of gastric cancer MGC803 and BGC823 cells were decreased after the low expression of PRSS1.2.PRSS1 is involved in the proliferation,migration and invasion of gastric cancer cells via the JAK2/STAT3 pathway.