HIF1A and metastatic neoplasm: Thromboembolic events, another cause of mortality in the control group, induce localized and systemic hypoxia, activating HIF pathways that exacerbate inflammation and coagulation [67] Additionally, metastatic neoplasms create hypoxic tumor microenvironments, which drive HIF-1α expression to promote angiogenesis and inflammatory signaling [68].