Comprehensive analyses of single-cell and bulk RNA-seq reveal the biological and prognostic roles of BMP4 in pancreatic adenocarcinoma

Bone Morphogenetic Protein 4 (<i>BMP4</i>) plays a critical role in development, but its function in pancreatic adenocarcinoma (PAAD) is not well understood. We found that <i>BMP4</i> is minimally expressed in the normal pancreas but markedly upregulated in PAAD, correlating with poor patient survival. Pan-cancer analysis revealed distinct expression and prognostic patterns of <i>BMP4</i>, while pathway analyses indicated that <i>BMP4</i> predominantly regulates metabolic rather than canonical BMP signaling. Single-cell RNA-seq showed <i>BMP4</i> enrichment in cancer cells and cancer stem cells, supporting its role in tumor metabolism. Importantly, <i>BMP4</i> was identified as an independent prognostic factor for PAAD, and a nomogram incorporating <i>BMP4</i> accurately predicted patient outcomes. Although <i>BMP4</i> affected certain immune cell infiltrations, its prognostic impact was largely independent of immune modulation. Collectively, these findings highlight <i>BMP4</i> as a potential biomarker and therapeutic target in PAAD.