Hedgehog/Gli2 Signaling Pathway Affects The Migration And Invasion Of Oral Squamous Cell Carcinoma And Its Molecular Mechanism

Objective:To investigate the role of hedgehog pathway in the carcinogenesis of oral squamous cell carcinoma(OSCC),we will establish an OSCC Chinese hamsters animal model to simulate the carcinogenesis of human OSCC.At the cellular level,we used Gli2,a key transcription factor downstream of hedgehog pathway,as the entry point to detect the effects of Gli2 on the proliferation,growth,migration and invasion of OSCC cells(Tca8113,Cal27,SCC9),and finally clarified the molecular mechanism of the hedgehog/Gli2 signaling pathway regulating tumor cell metastasis.The above research is expected to provide a new therapeutic target for OSCC.Methods:The chemical induction method was used to establish the OSCC Chinese hamsters animal model.H&E staining and transmission electron microscopy were used to observe the pathological characteristics of OSCC animal samples.In addition,the immunohistochemistry assay,q RT-PCR assay and western blot assay were used to detect the expression of hedgehog pathway related genes and proteins.At the cellular level,we first detect the expression of Gli2 gene and protein in different differentiated OSCC cells.The Gli2 expression in OSCC cells was inhibited by si RNA,and the effects of Gli2 expression on the expression of hedgehog pathway genes and proteins were detected by q RT-PCR and western blot.What’s more,CCK-8 assay,colony formation assay,scratch assay,transwell migration assay and matrigel invasion assay were used to detect the effect of Gli2 on OSCC cell proliferation,growth,migration and invasion.Meanwhile,q RT-PCR and western blot were used to detect the effect of Gli2 on the tumor metastasis marker genes and proteins downstream of the hedgehog pathway in OSCC.Results:The Chinese hamster OSCC animal model was successfully constructed,and the results of H&E staining assay and transmission electron microscopy assay showed that,after treatment with drugs for different periods of time,the Chinese hamster cheek pouch changed from normal epithelial tissue to simple hyperplastic epithelial tissue,further into abnormal hyperplastic epithelial tissue,and eventually evolved into OSCC.The animal tissue level results showed that hedgehog pathway genes and proteins were abnormally high expressed in OSCC animal samples,and the abnormal expression of these genes and proteins is an important marker of the activation of hedgehog pathway.It has been preliminarily confirmed that the hedgehog pathway is abnormally activated during the development of OSCC.At the cellular level,Gli2 expression increased in OSCC cell lines(Tca8113,Cal27,SCC9).In addition,interference with Gli2 expression can inhibit the expression of hedgehog pathway genes and proteins,which indicated that Gli2 plays a key role in the activation of the hedgehog pathway.What’s more,in different types of OSCC,inhibiting Gli2 expression can inhibit the proliferation,migration,invasion and growth of tumor cells.Further studies showed that,in OSCC cells,Gli2 may affect the migration and invasion of tumor cells by regulating the expression of cell metastasis marker genes and proteins downstream of the hedgehog pathway.Conclusion:Our study found that the hedgehog pathway is abnormally activated in OSCC,and Gli2 is a crucial transcription activator in the pathway.In OSCC cells,interference with Gli2 expression can inhibit the proliferation,migration,invasion and growth of OSCC cells.Further studies showed that,in OSCC cells,Gli2 affects the migration and invasion of tumor cells by regulating the expression of cell metastasis marker genes and proteins downstream of the hedgehog pathway.