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Background
Solute carrier family 35 member A2 (SLC35A2) located on the X chromosome is considered involved in the UDP-galactose transport from cytosol to Golgi apparatus and endoplasmic reticulum. It has been reported that the SLC35A2 expression is associated with carcinogenesis in recent studies, however, its specific roles in cancer progression have not been exhaustively elucidated. Herein, a system analysis was conducted to evaluate the role of SLC35A2 in prognostic, and immunology in stomach adenocarcinoma (STAD).
Methods
The TIMER, GEPIA, UALCAN, Kaplan–Meier Plotter were employed to explore the SLC35A2 expression pattern and prognostic value in STAD. Genomic alterations were searched through the MEXPRESS and cBioPortal platforms. The LinkedOmics, GEPIA and Metascape databases were employed to explore the biological processes. The TIMER and TISIDB websites were utilized to investigate the relationships between SLC35A2 expression and immune cell infiltration. The associations between SLC35A2 expression and tumor mutational burden (TMB), microsatellite instability (MSI) in pan-cancer were explored using the SangerBox database.
Results
Compared to the normal gastric mucosa, SLC35A2 expression was significantly increased in STAD tissues, accompanied by the robust relationships with tumor grade, histological subtypes, TP53 mutation status, TMB and prognosis. SLC35A2 and its co-expression genes played the primarily roles in purine metabolism and purinosome, including the asparagine N-linked glycosylation, protein processing in endoplasmic reticulum, regulation of transcription involved in G1/S transition of mitotic cell cycle, with the potential to participate in the regulation of VEGFA-VEGFR2 signaling pathway. Concurrently, SLC35A2 expression was correlated with macrophages and CD4+T lymphocytes infiltration in STAD.
Conclusions
Our study has proposed that SLC35A2 correlated with immune cell infiltration could serve as a prognostic biomarker in STAD.