Identification of circulating microRNA signature in pancreatic ductal adenocarcinoma and chronic pancreatitis patients from Indian population.

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal cancers, primarily due to late-stage diagnosis and the absence of reliable early biomarkers. Liquid biopsy has recently gained attention as a minimally invasive approach, with circulating microRNAs (miRNAs) emerging as promising diagnostic tools. However, most studies have been conducted in Western populations, and very few have systematically correlated tumor tissue and plasma-derived miRNA profiles or validated them in independent cohorts. The increasing incidence of pancreatic cancer in India, coupled with frequent misdiagnosis of chronic pancreatitis (CP) as PDAC owing to overlapping clinical symptoms and imaging features, underscores the urgent need for region-specific biomarkers. In this study, small RNA sequencing was performed on tumor tissues and plasma from patients with PDAC and CP. Integrated analysis revealed a set of deregulated miRNAs common to both sources. Among these, miR-21-3p, miR-193a-5p, and miR-636 were validated and demonstrated strong potential as non-invasive biomarkers for early detection of PDAC in Indian patients. Functional annotation further implicated these miRNAs in carcinogenic pathways and chemoresistance. Overall, this study highlights novel biomarkers with diagnostic utility and provides mechanistic insights into PDAC progression within the Indian population.