As the cell continues with the apoptotic process, surrounding cells rapidly engulf it and the cellular contents are reused. Role of Cell Death in Cancer Therapy Cancer therapies are currently designed to arrest and kill cancer cells, however they are non-selective. Traditional chemotherapy and radiation therapy kill all rapidly dividing cells, which includes both normal and cancerous cells. Thus, the usefulness of radiation and chemotherapy is limited by toxicity to normal cells, mainly in the bone marrow, gastrointestinal tract and skin. As a cell progresses from normal to malignant, it typically undergoes a variety of biochemical and genetic changes that gradually affect the cell's growth and appearance.
Tissues typically have more than one cell changing at the same time.
Carcinogenesis Continuum Chemoprevention Chemoprevention is the use of a drug to prevent cancer by either preventing or treating premalignant lesions. Chemoprevention is described as either primary or secondary. Primary chemoprevention is the prevention of a pre-malignant lesion from progressing to cancer. Secondary chemoprevention is the prevention of cancer recurrence, or to prevent cancer from coming back after it has been treated. Existing chemotherapeutic agents as well as radiation induce apoptosis in rapidly proliferating cells without differentiating between neoplastic and normal cells.