Solute Carrier Family 35 A2 (SLC35A2) Promotes Tumor Progression through MYC-Mediated Pathways in Colorectal Cancer

Colorectal cancer (CRC) is one of the most prevalent cancers, posing a significant threat to human life. Although therapeutic approaches for advanced-stage patients have improved in recent years, there is still room for enhancing treatment response. Recent evidence suggests that dysregulation of nucleotide sugar transporters (NSTs) is associated with the development and progression of tumors. Therefore, this study aims to explore the potential therapeutic and prognostic implications of the solute carrier family 35 A (SLC35A) members in CRC. To achieve this, we performed integrative bioinformatics analysis using various publicly available databases, including GENT2, TCGA, UALCAN, cBioPortal, Kaplan-Meier plotter, The ROC plotter, GDSC, TISIDB, and TIMER. We compared gene expression profiles between CRC tumors and adjacent normal tissues, revealing that only SLC35A2 exhibited significant upregulation in tumors, while the other family members were downregulated. Additionally, higher SLC35A2 expression was found in microsatellite stable (MSS) colorectal tumors. Further analysis of TCGA and GEO datasets showed that patients with high SLC35A2 expression experienced poorer relapse-free survival. Next, we conducted gene set enrichment analysis (GSEA), and the results indicated that the upregulation of SLC35A2 is linked to cellular metabolism pathways, such as MYC Targets V2, Steroid Biosynthesis, Pentose Phosphate Pathway, and TCA Cycle. Furthermore, our CRC cell models revealed the tumor-promoting role of SLC35A2 and discovered that the upregulation of SLC35A2 is associated with chemoresistance against irinotecan. Additionally, we observed a negative correlation between SLC35A2 expression and the infiltration of immune cells, particularly cytotoxic CD8+ T cells and B cells. This suggests the immunomodulatory role of SLC35A2. In summary, SLC35A2 is abnormally upregulated in CRC, and patients with high SLC35A2 expression tend to have poor relapse-free survival. This may be due to its involvement in regulating cancer cell metabolic reprogramming, promoting tumor progression, modulating the immune landscape, and influencing treatment response. Consequently, SLC35A2 could serve as a significant prognostic factor and a potential therapeutic target in CRC.