Cancer remains the most lethal disease globally, despite the significant progress made in early screening, surgery, and therapeutic development in recent decades. Programmed cell death (PCD) is a genetically regulated process essential for eliminating aberrant cells, yet its dysregulation drives tumorigenesis and therapy resistance. In this review, we present a complete discovery timeline of them and comprehensively synthesize the roles and mechanisms of major PCD forms, such as apoptosis, necroptosis, autophagy, pyroptosis, ferroptosis, and cuproptosis, across diverse cancer types. We not only detail the molecular mechanisms, dual functions, and alterations of these PCD modalities in cancers, but also summarize their interconnections and intrinsic crosstalk. Furthermore, we comprehensively discuss how diverse therapies, including chemotherapy, radiotherapy, immunotherapy, targeted agents, and hormone therapy, engage and manipulate specific PCD pathways, revealing the involvement of PCD in cancer treatment mechanisms. This review integrates extensive preclinical and clinical evidence on PCD-targeted therapies with an in-depth focus on ferroptosis, including its regulatory networks and therapeutic relevance. Special emphasis is placed on prostate cancer, highlighting the PCD-based translational opportunities in this common malignancy. Taken together, we provide novel insights into the complex interplay between PCD and cancer biology and offer a framework for developing precision oncology therapies.