The Mechanism Of LAMC1 And PLAU Regulating The Activation Of CAF In Microenvironment And Promoting The Progression Of Esophageal Squamous Cell Carcinoma

Esophageal cancer has high incidence,high degree of malignancy and poor prognosis.The five-year survival rate hovers between 15%and 25%.According to histological types,esophageal carcinoma is mainly divided into esophageal squamous cell carcinoma(ESCC)and esophageal adenocarcinoma(EAC).Esophageal squamous cell carcinoma accounts for more than 90%of esophageal cancer,and ESCC is also a characteristic cancer in China.We need to further study the molecular biological mechanism of the occurrence and development of ESCC to provide a new research basis for its treatment.Recently,more and more attention has been paid to tumor microenvironment(TME),which plays an important role in promoting tumor proliferation,inhibiting tumor apoptosis and causing immune escape.TME is mainly composed of various cells,such as immune cells,fibroblasts,endothelial cells,as well as extracellular matrix(ECM)and cytokines.Those cells could interact with each other through cytokines.Cancer associated fibroblast(CAF),as an important component of tumor microenvironment,plays an important role in development of tumor cells.CAF can secrete cytokines,reshape extracellular matrix,promote angiogenesis,and promote tumor proliferation,migration and recurrence.CAF can play an important role in the occurrence,development,drug resistance and metastasis of ESCC through the secretion of various cytokines,including HGF,IL-6,CXCL1,PAI-1.Like tumor cells,CAF also has heterogeneity,such as pro-tumor CAF and anti-tumor CAF in gastrointestinal tumors;inflammatory CAF and myofibroblasts in pancreatic ductal carcinoma.Heterogeneity of CAFs could be influenced by tumor cells or other cells through paracrine cytokines.At the same time,transforming growth factor-beta(TGF?),as an important cytokine in the tumor microenvironment,not only plays a dual role in the progression of tumor cells directly,but also influences tumor cells by regulating the heterogeneity of CAFs.We focus to find potential therapeutic targets that can indirectly influence the progression of tumor cells through TME,not only targeting the tumor cells themselves.Here,we explored oncogenes regulated by TGF?,which were involved in signaling molecules and interactions in TME.We analyzed the sequencing data of TCGA and GEO53625,as well as ESCC cell lines with or without TGF?-1 stimulation,then we focused on LAMC1.We verified that LAMC1 was highly expressed in ESCC,affecting the prognosis of patients.Meanwhile,LAMC1 was up-regulated by TGF? through SMAD4 and SP1 synergistic activation.Further experiments showed that LAMC1 promoted proliferation and migration of tumor cell via Akt/NF-?B/MMP9 and MMP14.Additionally,LAMC1 facilitated CXCL1 secretion via NF-?B.CXCL1 secreted by tumor cell promoted the formation of inflammatory CAFs(iCAFs)through CXCR2/pSTAT3.The conditional medium of iCAFs promoted proliferation and migration of tumor cell.In summary,our study provided the mechanism that upregulation of LAMC1 by TGF? in tumor cells not only promoted ESCC progression,but also played indirectly carcinogenesis by stimulating CXCL1 secretion and promoting the formation of iCAFs.It suggested that LAMC1 could be a potential therapeutic target and prognostic marker for ESCC.Cancer-associated fibroblast(CAF)plays an important role in the tumor microenvironment.The heterogeneity of CAF affects the effect of CAF on promoting or inhibiting tumors,which can be regulated by other cells in the tumor microenvironment through paracrine methods.The plasminogen activator,urokinase(PLAU)system mediates cell proliferation,migration,adhesion and other fimctions through the proteolytic system,intracellular signal transduction,and chemokine activation.PLAU promotes tumor progression in many tumors.We explored the function of PLAU in ESCC and the influence of PLAU secreted by tumor cells on the heterogeneity of CAF.We found that PLAU is highly expressed in ESCC,which is related to poor prognosis and can be used as a prognostic marker for ESCC.Through loss-and gain-of function experiments,we found that PLAU promoted ESCC proliferation and clone formation via MAPK pathway,and promotes migration by upregulating Slug and MMP9,which can be reversed by the Mek 1/2 inhibitor U0126.At the same time,through sequencing,cytokine detection,and RT-qPCR verification,we found that tumor cells secreted PLAU promoted the conversion of fibroblasts to inflammatory CAF,which upregulated expression and secretion of IL8 via the uPAR/Akt/NF-KB pathway.The IL8 secreted by CAFs in turn promotes the high expression of PLAU in tumor cells and further promoted the progression of ESCC.In Summary,PLAU was not only a prognostic marker of ESCC,which promoted tumor cell proliferation and migration,but also promotes the formation of inflammatory CAF by the PLAU secreted by tumor cells.