title: Overexpression of LRIG1 regulates PTEN via MAPK/MEK signaling pathway in esophageal squamous cell carcinoma.
abstract: The present study aimed to evaluate the role of leucine-rich repeats and immunoglobulin-like domain protein 1 (LRIG1) in the regulation of phosphatase and tensin homolog (PTEN) expression in esophageal carcinogenesis.LRIG1was overexpressed in esophageal squamous cell carcinoma (ESCC) cell lines, and the effect ofLRIG1overexpression on the mRNA and protein expression levels ofPTENwas evaluated by reverse transcription-quantitative polymerase chain reaction and western blotting. Furthermore, the effects ofLRIG1overexpression on the cell cycle distribution and apoptosis of ESCC cells were examined by flow cytometry. Various cell signaling pathway inhibitors were used to assess the effects ofLRIG1on downstream signaling in ESCC cell lines. In addition, the association betweenLRIG1andPTENexpression was examined in 48 samples from patients with ESCC.LRIG1overexpression was demonstrated to downregulatePTENexpression in ESCC cell lines, and promote their proliferation and inhibit apoptosis. In addition, LRIG1-mediated suppression ofPTENexpression was inhibited by the U0126 inhibitor, which suggests that LRIG1 may inhibit the activation of PTEN signaling molecules by triggering the mitogen-activated protein kinase (MAPK)/MAPK kinase 1 (MEK) signaling pathway. In conclusion, the present study demonstrated that overexpression ofLRIG1significantly and adversely affected the survival of ESCC cells, and that the MAPK/MEK signaling pathway may be responsible for the repression ofPTENexpression and function.
authors.affiliation: Central Laboratory, Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Department of Biochemistry, School of Basic Medicine, Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China; Tumor Institute, Affiliated Tumor Hospital, Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Huiwu
authors.initials: H
authors.lastname: Li
keywords: esophageal squamous cell carcinoma; leucine-rich repeats and immunoglobulin-like domain protein 1; phosphatase and tensin homolog; signaling pathway