Mechanisms of apoptotic dysregulation in oncogenesis and targeted therapeutic interventions

Apoptosis is a regulated form of programmed cell death mechanism that is essential for maintaining cellular homeostasis, embryonic development, and genomic integrity. Dysregulation of this orchestrated process is a fundamental hallmark of cancer, where an imbalance between pro-apoptotic (p53, Bax) and anti-apoptotic factors (Bcl-2, Bcl-xL) facilitates malignant transformation, tumor progression, and metastasis. While insufficient apoptosis drives oncogenesis, the integrity of these death pathways is also a critical determinant of therapeutic success; most current chemotherapeutic agents rely on intact apoptotic signaling to eradicate malignant cells. Consequently, molecular defects within the extrinsic or intrinsic pathways frequently result in multidrug resistance (MDR), limiting clinical efficacy. Recent clinical experience with Bcl-2 inhibitor venetoclax illustrates both the potential and the limitations of apoptosis-directed precision therapy: responses are substantial in selected hematologic malignancies, but resistance can emerge through clonal evolution and dependence on alternative anti-apoptotic proteins such as Mcl-1 or Bcl-xL. This review delineates the fundamental regulators of the apoptotic machinery and examines how their functional inactivation or overexpression contributes to therapeutic evasion. Furthermore, we evaluate emerging strategies designed to bypass resistance by modulating apoptotic sensitivity. While pharmacological targeting of apoptosis remains a promising frontier in oncology, translating these novel therapies from bench to bedside requires rigorous validation of safety and systemic toxicity to ensure clinical viability.