Identification of gemcitabine resistance-related AHNAK2 gene associated with prognosis and immune infiltration in pancreatic cancer.

Purpose: Gemcitabine is a basic chemotherapy drug for pancreatic cancer (PC), but resistance is common and causes tumor recurrence and metastasis. Therefore, it is significant to explore gemcitabine resistance-related molecules for individualized treatment and prognosis assessment of PC.

Methods: In this study, transcriptome sequencing and TCGA database analysis were performed, and a differentiated gene AHNAK2 was screened. MEXPRESS database, tissue microarray analysis, and CIBERSORT and TIMER databases were used to correlate AHNAK2 expression with clinicopathological features and prognosis and immune infiltration of PC. Enrichment analysis was used to investigate the significant biological processes associated with AHNAK2.

Results: AHNAK2 was highly expressed in gemcitabine-resistant cells. High expression of AHNAK2 increased the risk of poor overall survival (OS) and progression-free survival (PFS) in PC. Clinicopathologic analysis revealed that AHNAK2 correlated with KRAS, TP53 mutations, histologic type, short OS, N stage, and elevated CA199 levels in PC. Knockdown of AHNAK2 inhibited the ability of cell proliferation and colony formation and enhanced the toxic effect of gemcitabine in PC. Meanwhile, the knockdown of AHNAK2 expression enhanced cell-ECM adhesion, inhibited cell-cell adhesion, and downregulated the KRAS/p53 signaling pathway in PC. Furthermore, AHNAK2 was correlated with immune infiltration, especially B cells and macrophages.

Conclusions: Our study unveils for the first time the pivotal role of AHNAK2 in PC, particularly its association with gemcitabine resistance, clinical prognosis, and immune infiltration. AHNAK2 not only drives the proliferation and drug resistance of PC cells by potentially activating the KRAS/p53 pathway but also significantly impacts cell-cell and cell- ECM adhesion. Additionally, AHNAK2 plays a crucial role in modulating the tumor immune microenvironment. These insights underscore AHNAK2's unique potential as a novel therapeutic target for overcoming gemcitabine resistance, offering new perspectives for PC treatment strategies.