LRIG1 Gene Expression and Signaling Pathway and Prognosis in Non-Small Cell Lung Cancer
HUANGXin,HUA Feng
Department of Thoracic Surgery, Jinghai District Hospital, Tianjin (301600), China.
Abstract:
Objective To investigate the expression of LRIG1 gene in patients with non-small cell lung cancer (NSCLC), its signal pathway and its relationship with prognosis. Methods The expression level of LRIG1 gene mRNA in NSCLC patients was analyzed in TCGA database. The LRIG1 protein-protein interaction network was constructed in string database and the related protein function and KEGG signal pathway were enriched. The relationship between LRIG1 gene expression and total survival (OS) and disease free survival (DFS) of NSCLC patients was analyzed. We selected 96 patients with NSCLC who were operated in our hospitaland detected the LRIG1 protein in cancer tissue and adjacent tissue by immunohistochemistry, then verified the results of database analysis. Results In NSCLC, the expression level of LRIG1 gene was higher in normal tissues but lower in cancer tissues.The 10 protein interaction network with LRIG1 protein was enriched significantly (P <0.001). The co-expression analysis showed that the positive co-expression of CACNAID gene and LRIG1 gene was the most signi?cant (r = 0.51, P< 0.05), while the negative co-expression of RGS20 gene and LRIG1 gene was the most signi?cant (r =–0.49). The biological process, cell composition and molecular function of LRIG1 gene are mainly enriched in negative regulation of epidermal growth factor receptor signal pathway, cytoplasmic vesicle and phosphatidylinositol-4,5-diphosphate 3-kinase activity, etc. The LRIG1 gene is mainly enriched in proteoglycan, endocytosis, MAPK signal pathway, PI3K Akt signal pathway and Rap1 in cancer. The OS rate of patients with high expression of LRIG1 gene mRNA (HR = 0.74, P< 0.05) was higher than that of patients with low expression of LRIG1 gene mRNA, but there was no statistical difference in patients with high or low expression of DFS (HR = 1.0, P = 0.97).The positive expression rate of LRIG1 protein in NSCLC adjacent tissues was signi?cantly higher than that in cancer tissues (P< 0.05). The high expression of LRIG1 was related to clinical stage, tumor size and mediastinal lymph node metastasis (P< 0.05). Conclusion The expression of LRIG1 gene is low in NSCLC, which is related to tumor size, lymph node metastasis and overall survival.
