Mechanism of interaction between TM4SF1 and jak2-stat3 signaling pathway in lung cancer cells and expression analysis in non-small cell lung cancer
Authors: Niu Yumeng , Deng Hailong , Li Lipeng , Chen Weikang , Wang Yuxuan , Xian Lei 
Published: May 2020

Abstract
Background According to the latest data released in 2018, it is estimated that there will be 18.1 million new cancer cases worldwide (excluding 1.7 million non-melanoma skin cancers) and 9.6 million cancer deaths (excluding 950 non-melanoma skin cancers) Million cases). Among them, the incidence of lung cancer (11.6% of the total number of cases) and mortality (18.4% of the total number of cancer deaths, which are expected to cause 1.8 million deaths) are the first. In recent years, studies have found TM4SF1 play an important role in the development process of many tumors.Methods Sixty-one patients with NSCLC who underwent surgical resection of cancer tissues, para-carcinoma tissues, and 10 normal lung tissues removed from benign lung disease (Jun/2018-Dec/2018) were collected. Real-time immunofluorescence quantitative PCR (qRT-PCR) and Western blot were used to detect the expression of TM4SF1 in NSCLC tissues (CT), para-carcinoma tissue (PCT), and normal lung tissues(NLT). TM4SF1 gene was overexpressed in lung cancer A549 cells using lentiviral transfection technology, qRT-PCR and Western blot were used to detect whether TM4SF1 gene was successfully expressed in lung cancer A549 cells, and Transwell was used to detect the effect of TM4SF1 overexpression on A549 migration. JAK2-STAT3 signal pathway interference reagent AG490 was used to analyze the expression levels of Stat3 and downstream Sox2 genes in the overexpression group, blank group, negative control group and their corresponding treatment groups TM4SF1, JAK2-STAT3 signal pathway using real-time qRT-PCR. Analyze the relevance of these three indicators at the same time.Results The expression levels of TM4SF1 mRNA and protein in cancer tissues were significantly higher than those in adjacent cancer tissues (P<0.05) and normal lung tissue specimens (P <0.05). The expression of TM4SF1 was not significantly associated with the age and sex of patients, but was associated with tumor size, degree of differentiation, lymph node metastasis, and clinical stage were related (P<0.05). TM4SF1 was successfully overexpressed in A549 cells. After overexpressing TM4SF1, the ability to migrate of A549 cells was significantly enhanced, and the expression levels of Stat3 and downstream Sox2 in the JAK2-STAT3 signaling pathway were up-regulated. The expression of TM4SF1, Stat3 and Sox2 at the mRNA level showed a positive correlation trend (P<0.01).Conclusion TM4SF1 is highly expressed in NSCLC, and its expression level is closely related to many clinical staging indicators. Overexpression of this gene can promote the migration of A549 cells and up-regulate the expression levels of Stat3 and downstream Sox2 in the JAK2-STAT3 signaling pathway. The expressions of TM4SF1, Stat3 and Sox2 were positively correlated in A549 cells. TM4SF1 may promote the occurrence, development and distant metastasis of NSCLC through this pathway. TM4SF1 may become a potential therapeutic target for NSCLC.