Cardiovascular Diseases and Cancer: Convergent Proteostasis Networks at the Crossroads of Mechanisms and Therapeutic Opportunities.

Cancer and cardiovascular diseases, the primary causes of mortality globally, are increasingly understood as biologically interconnected rather than distinct pathologies. Recent evidence indicates that protein homeostasis (proteostasis) functions as a crucial molecular link connecting tumor progression, therapeutic resistance, cardiac remodeling, and treatment-related cardiotoxicity. Proteostasis, which encompasses the cellular processes of protein synthesis, folding, quality control, and degradation, dictates tissue adaptation to chronic stress. Notably, the adaptive mechanisms that allow tumor cells to endure proteotoxic stress and resist therapy are often vital for maintaining cardiac structure and function. Thus, tumor control and cardiovascular injury may be divergent outcomes of a common stress-response framework. In this review, we propose proteostasis as a comprehensive framework for understanding the cancer-cardiovascular interface. We analyze how the ubiquitin-proteasome system, autophagy-lysosome pathway, endoplasmic reticulum stress-induced unfolded protein response signaling, and molecular chaperone networks are differentially reconfigured in cancer and cardiac tissues, influencing tumor survival, therapeutic susceptibility, and cardiovascular dysfunction. Additionally, we explore the translational implications of proteostasis dysregulation, including mechanisms of anticancer therapy-induced cardiotoxicity, emerging biomarkers, cardioprotective strategies, and opportunities for precision cardio-oncology. By conceptualizing efficacy and toxicity as interconnected outcomes of shared proteostasis biology, this review establishes a foundation for developing therapies that optimize cancer control while safeguarding cardiovascular health.