ITGB5-mediated biomechanical regulation in pancreatic ductal adenocarcinoma stroma impacts tumor progression and prognosis.

backgroundPancreatic ductal adenocarcinoma (PDAC) is characterized by stromal remodelling andstiffening, a process involving extracellular matrix (ECM) depositionand cross-linking, which forms a dense physical barrier that limits the penetration of chemotherapeutic agents and restricts immune cell-mediated cytotoxicity. In addition, the tumor stroma modulates nutrients availability and fosters cancer cell invasion and metastasis. Therefore, therapeutic strategies aimed at modulating the tumor stroma hold promise for overcoming some of the major challenges in pancreatic cancer treatment. However, most clinical trials of stromal-targeted therapies have not demonstrated meaningful improvements in overall survival, underscoring an urgent need to identify novel stromal targets and approaches that modulate the tumor microenviroment in ways that enhance therapeutic response and improve patient outcomes.

methodsTranscriptomic datasets of PDAC sampleswere obtained from The Cancer Genome Atlas (TCGA). By integrating immune infiltration algorithms with weighted gene co-expression network analysis (WGCNA), this study aims to identify hub genes associated with cancer-associated fibroblasts (CAFs) infiltration in PDAC, explore the prognostic relevance of CAF infiltration, and construct a gene‑expression-based prognostic mode. Furthermore, we will employ a multi-modal approach incorporating magnetic resonance elastography, atomic force microscopy, single-cell RNA sequencing (scRNA-seq), histological assays, cell-based functional experiments, and animal models to identify candidate core genes involved in CAF infiltration and stromal stiffening in pancreatic cancer, and to assess the potential therapeutic relevance of targeting these genes.

resultsIn PDAC, increased stromal stiffness and poor prognosis are both strongly linked to activation of CAFs. WGCNA identified six hub genes-ANTXR2, ANXA1, BCAT1, PLAU, TGFβ1, and ITGB5-which were used to construct a predictive model for estimating CAF abundance and forecasting PDAC prognosis. Single-cell RNA sequencing analysis showed that ITGB5 is highly expressed in CAFs. Both in vitro and in vivo experiments demonstrated that targeting ITGB5 in CAFs reduces tumor stiffness, thereby inhibiting the malignant progression of PDAC. These findings suggest a potential therapeutic benefit, although impact on clinical prognosis remains to be established.

conclusionThe integration of magnetic resonance elastography, atomic force microscopy, and single-cell sequencing allows detailed research characterization of the biomechanical properties of PDAC. ITGB5 has been identified as an important regulator of the biomechanical features of PDAC. Targeting ITGB5 in CAFs may reduce the excessive stiffness of PDAC tissue and mitigate gemcitabine-associated stromal fibrosis, suggesting a potential strategy to improve treatment response. The effect on patient prognosis, however, requires confirmation in clinical studies.

trial registrationThis study is a prospective single-center clinical trial, which has been registered in the U.S. Clinical Trials Database ( https://clinicaltrials.gov/study/NCT06526442 ) with the trial registration number NCT06526442. The registration date was October 9th, 2020.