Expression Of PGRP-S In Hepatocellular Carcinoma And Remodeling Of Hepatocellular Carcinoma Microenvironment

BackgroundHepatocellular Carcinoma（HCC）is a common malignant tumor of the digestive system.The disease progresses rapidly and is difficult to detect in its early stage.Most patients are already in the advanced stage when symptoms appear,and the prognosis is not ideal.It is believed that the mechanism of the occurrence and development of hepatocellular carcinoma is the result of the interaction between hepatocellular carcinoma cells and their microenvironment.Tumor infiltrating Lyphocytes（TILs）are representative components of tumor microenvironment.It has been reported that lymphocytes can secrete Peptidoglycan recognition protein S（PGRP-S,PGLYRP1,Tag7）,which is a member of the pattern recognition family.The PGRP-S-MTS1（calcium-binding protein S100A4）complex induces lymphocyte migration.The expression and mechanism of PGRP-S in the microenvironment of liver cancer have not been reported.Therefore,this project intends to further explore the expression localization and role of PGRP-S in the microenvironment of liver cancer.ObjectiveThe expression of PGRP-S in hepatocellular carcinoma cells and its effect on the proliferation and migration of hepatocellular carcinoma cells were detected to clarify the role of p GRP-S in the progression of hepatocellular carcinoma.To investigate the effects of PGRP-S on HCC cells and TILs in tumor microenvironment,in order to provide new ideas for immunotherapy of HCC.Methods1.The expression of PGRP-S m RNA in HCC cells（LM3,Hep G2,SMMC7721,97 H,97L,Huh7）and normal hepatocytes（LO2）was detected by real-time quantitative PCR（q RT-PCR）;the expression of PGRP-S in 45 HCC paraffin tissue samples was detected by immunohistochemistry（IHC）assay,and finally the relationship between different expression of PGRP-S in HCC tissues and clinicopathological parameters such as patient age and lymph node metastasis was examined by statistical methods.2.The cell line with silent expression of PGRP-S in HCC cells was constructed by transient transfection,and then the silencing efficiency of PGRP-S in HCC cells was examined by Western blotting（WB）assay.3.The effects of different PGRP-S gene expression levels on hepatoma cell proliferation and Hep G2 cell migration were detected by cell function assays: scratch healing,transwell,plate cloning,and CCK-8 assay.4.The effects of PGRP-S factor and T lymphocytes on the expression of PGRP-S in hepatocellular carcinoma cells were detected by immunofluorescence technique（IF）.Transwell assay was used to observe the effects of PGRP-S factor and T lymphocytes on the migration ability of hepatoma cells.5.The effects of PGRP-S factor and hepatoma cells on the expression of PGRP-S in T lymphocytes were detected by immunofluorescence assay.Transwells were used to detect the effects of PGRP-S cytokines and hepatoma cells on the migration ability of T lymphocytes.Results1.The expression of PGRP-S in hepatocellular carcinoma tissues was significantly higher than that in paracancer tissues,and was positively correlated with the degree of differentiation and lymph node metastasis.2.PGRP-S silencing can significantly reduce the proliferation and migration of HCC cells;3.PGRP-S secreted by T lymphocytes can induce migration and nuclear expression of HEPATocellular carcinoma cells,and PGRP-S secreted by hepatocellular carcinoma cells can enhance the migration ability and expression of T lymphocytes.ConclusionPGRP-S promotes the proliferation and migration of HCC cells and regulates the remodeling of HCC microenvironment.