The expression characteristics of ABHD8 and its potential role in prognosis assessment and immune escape mechanism of colorectal cancer

Objective This study aims to comprehensively assess the expression pattern and clinical relevance of ABHD8, a member of the fatty acid amide hydrolase family, in colorectal cancer (CRC). Methods Expression profiles and clinical data related to ABHD8 were obtained from the TCGA database. Differential expression between tumor and adjacent normal tissues was analyzed using the Wilcoxon rank sum test. The chi-square test was applied to explore associations between ABHD8 expression and various clinicopathological parameters. Prognostic implications were evaluated using univariate and multivariate Cox regression models as well as Kaplan–Meier survival analysis. Correlations between ABHD8 and immune cell infiltration, along with immune checkpoint molecules, were further investigated. Results Analysis of TCGA datasets revealed that ABHD8 exhibits differential expression across multiple cancer types, with a notably reduced expression in CRC tissues compared to matched normal tissues (P < 0.001), suggesting its potential role as a diagnostic indicator. Further statistical analysis demonstrated that low ABHD8 expression was significantly linked to pathologic N stage (P = 0.001), overall clinical stage (P = 0.011), and lymphatic vessel invasion (P < 0.001). Prognostic modeling indicated that ABHD8 serves as an independent factor influencing overall survival in CRC patients (HR = 3.222, 95% CI: 1.521–6.821, P = 0.002), and a nomogram incorporating ABHD8 was developed, showing favorable predictive accuracy. Kaplan-Meier survival curves showed a significant association between elevated ABHD8 expression and poorer prognosis (log-rank P < 0.001, AUC > 0.6). Single-cell transcriptomic analysis revealed that ABHD8 is predominantly expressed in Tprolif, CD8T, and CD8Tex cells, while its expression in dendritic cells (DCs) and monocyte/macrophage lineages was comparatively lower, indicating cell-type specificity. Furthermore, ABHD8 expression demonstrated strong positive correlations with the infiltration levels of several immune cells, particularly immunosuppressive subsets such as iDCs, NK cells, and regulatory T cells (Tregs) (all R > 0.37, P < 0.001). In addition, ABHD8 expression was positively associated with immune checkpoints PDCD1 (R = 0.328) and CD274 (R = 0.082), but negatively correlated with CTLA4 (R = − 0.155, P < 0.001), implying a possible role in immune evasion mechanisms. Conclusion These findings suggest that ABHD8 holds promise as a novel immune-associated biomarker with both diagnostic and prognostic value in colorectal cancer.