Molecular Pathways in Cancer: Targets for Therapy

Cancer is characterized by uncontrolled cellular proliferation driven by genomic instability, dysregulated signaling pathways, and altered cellular metabolism. Despite significant advances in diagnosis and treatment, cancer remains a leading cause of global morbidity and mortality. Central to carcinogenesis is the activation of proto-oncogenes such as EGFR, MYC, and RAS, coupled with the inactivation of tumor suppressor genes like TP53, resulting in disrupted cell cycle control, defective DNA repair, and metabolic reprogramming. Key molecular pathways—including Hippo, MYC, p53, LKB1/AMPK, PI3K/AKT/mTOR, and RAS/RAF/MEK/ERK—enable cancer cells to adapt to metabolic stress, evade apoptosis, and sustain uncontrolled growth. In parallel, defects in DNA repair mechanisms, particularly those involving PARP-mediated repair, further contribute to tumor progression. Advances in the understanding of these molecular pathways have facilitated the development of targeted therapies, including small-molecule kinase inhibitors and monoclonal antibodies, which offer improved specificity and reduced toxicity compared with conventional chemotherapy. A comprehensive understanding of cancer biology at the molecular level is essential for the development of effective targeted therapies and for improving clinical outcomes.