The Effect Of YBX3 On The Growth Of Tongue Squamous Cell Carcinoma Cells And Its Molecular Mechanism

Background:Tongue squamous cell carcinoma(TSCC)is currently the highest incidence of oral cancers,with a high rate of regional lymph node metastasis and recurrence,but the specific mechanism of its occurrence and development is still not clear.Studies have confirmed that YBX3 plays a vital role in many types of cancer,and can affect tumor proliferation,invasion and migration.However,there has not been any research on YBX3 in tongue squamous cell carcinoma so far.Objective:To study the expression of YBX3 in tongue squamous cell carcinoma tissues,and its influence on the growth of tongue squamous cell carcinoma cells and its molecular mechanism.Methods:We collected 35 cases of tongue squamous cell carcinoma samples and 2 cases of normal tongue squamous epithelium tissue samples,and analyzed the expression of YBX3 in the tissues by immunohistochemical staining.Human tongue squamous cell carcinoma lines CAL27 and Tca-8113 were cultured in vitro.YBX3 expression in the cells was knocked down by siRNA technology,and then q RT-PCR and Western Blot were used to detect knockdown efficiency.After down-regulation of YBX3,cell proliferation was detected by Ed U assay,cell cycle was detected by flow cytometry,autophagy was observed by CYTO-ID staining under the confocal microscope,and the protein expression of proliferation,cycle and autophagy-related factors and changes in signaling pathway-related proteins were detected by Western Blot.Results:The immunohistochemical staining results revealed that YBX3 was positively expressed in tongue squamous cell carcinoma samples and the level of YBX3 expression was negatively correlated with the degree of tumor differentiation,in detail,lower YBX3 expression in well-differentiated and higher level in moderate/poor-differentiated tumors;meanwhile,YBX3 expression positively correlated with the patient’s age,that is,YBX3 expression was weaker in samples younger than 60 years old,and was stronger in samples older than or equal to 60 years old.In vitro assays demonstrated that down-regulation of YBX3 inhibited cell proliferation,caused cell cycle arrest,and activated autophagy.The Wnt/β-Catenin and m TOR signaling pathways were inhibited following YBX3 down-regulation.Conclusions:YBX3 is positively expressed in tongue squamous cell carcinoma samples,and is correlated with the degree of differentiation and age of patients with tongue squamous cell carcinoma.Down-regulation of YBX3 in tongue squamous cell carcinoma cells suppresses cell growth and induces autophagy through Wnt/β-Catenin and m TOR signaling pathways.