Systemic Analyses of the Expression of TPI1 and Its Associations with Tumor Microenvironment in Lung Adenocarcinoma and Squamous Cell Carcinoma

BACKGROUND: Recent studies have shown that the expression level of triosephosphate isomerase 1 (TPI1) may be associated with the occurrence and metastasis of tumors, but the expression level of TPI1 and its effect on lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC) are not yet clear. METHODS: We comprehensively explored and validated the TPI1 expression in lung adenocarcinoma and lung squamous cell carcinoma in public datasets. The associations of TPI1 expression with clinicopathological characteristics and prognosis were also studied in both histological types. Moreover, we analyzed the potential relations of TPI1 with immunomodulators and immune cell infiltrations in the tumor microenvironment based on previous literatures and bioinformatic tools. RESULTS: We found that TPI1 was significantly overexpressed in LUAD and LUSC. Significant associations of TPI1 expression were observed regarding age, gender, and pathological stages in LUAD. However, similar trend was only found with respect to age in LUSC. The high expression of TPI1 was significantly associated with worse survival in LUAD, but not in LUSC. Furthermore, we explored the potential distribution and changes of TPI1 expression in tumor microenvironment. Pathway enrichment analyses were performed to identify possible roles of TPI1 in both lung cancers. CONCLUSIONS: TPI1 was overexpressed in both LUAD and LUSC. Increased TPI1 expression was correlated with poor prognosis in LUAD and changed immune cell infiltrating in various degrees in both histological types. Our study provides insights in understanding the potential roles of TPI1 in tumor progression and immune microenvironment.