From Single-Cell Sequencing Data Analysis to Functional Validation: XCL1 is Associated with Glycolytic Metabolism in Oral Squamous Cell Carcinoma.

Objective

Oral squamous cell carcinoma (OSCC) is a head and neck cancer with high morbidity and mortality. Glycolytic metabolism plays a crucial role in its progression, yet the molecular mechanisms regulating glycolysis in OSCC remain unclear.

Design

Single-cell RNA sequencing of the GSE247582 dataset was used to identify cell subsets, analyze metabolic pathway enrichment, and screen core candidate genes. TCGA data were used to validate gene expression. In vitro gain- and loss-of-function experiments, together with glycolysis inhibition, were performed to assess the effects of XCL1 on cell proliferation, apoptosis, and glycolysis-related metabolic parameters.

Results

Five cellular subgroups were identified, each with distinct metabolic characteristics. The glycolysis/gluconeogenesis pathway was markedly active in specific subsets. Fifteen candidate genes were identified through differential expression analysis, of which seven were significantly upregulated in OSCC tissues in both paired and unpaired TCGA analyses. XCL1 showed the most pronounced and consistent upregulation among the validated candidates and was selected for functional investigation. XCL1 knockdown significantly suppressed OSCC cell proliferation, induced apoptosis, and reduced glucose uptake, lactate production, ATP levels, LDH activity, and the expression of glycolytic enzymes, including HK2, PKM2, and LDHA. Conversely, XCL1 overexpression enhanced OSCC cell proliferation and glycolysis-related metabolic parameters and reduced apoptosis, whereas 2-DG attenuated these effects.

Conclusions

XCL1 is associated with glycolysis-related metabolic alterations and OSCC cell growth in vitro. These findings support further investigation of XCL1 in OSCC, while in vivo studies and larger clinical cohorts are needed to further evaluate its biological and therapeutic relevance.