An overview of molecular mechanisms in cancer drug resistance and therapeutic strategies

Cancer resistance refers to the ability of cancer cells to evade the effects of treatments, such as chemotherapy and radiation, making it challenging to eliminate tumors. Cancer cells develop resistance through genetic modifications, alterations in cellular pathways, or microenvironmental adaptations that allow cancer cells to persist, proliferate, and even thrive despite the application of therapies designed to eradicate them. Despite efforts to create more potent target-based drugs, the flexibility of acquired resistance necessitates advanced options. Combination therapy and precision immunotherapy has revolutionized treatment but is limited by patient specificity and requires further development. New approaches like small molecules, peptides, and nanotherapeutics aim to overcome resistance by enhancing site-specific delivery and increasing drug concentration inside cancer cells. This review provides a comprehensive overview of the molecular mechanisms underlying cancer drug resistance, including genetic mutations, epigenetic alterations, efflux pump activity, and the influence of the tumor microenvironment. Additionally, the roles of microRNAs, long noncoding RNAs, and cellular processes such as autophagy and hypoxia in mediating resistance are examined. This review seeks to improve patient care and help to the development of more effective cancer medicines by explaining these complicated systems and investigating novel therapeutic alternatives.