Targeting of cancer cell death mechanisms by curcumin: Implications to cancer therapy

Cancer is known as a second major cause of death globally. Nowadays, several modalities have been developed for the treatment of cancer. Radiotherapy and chemotherapy are the most common modalities in most countries. However, newer modalities such as immunotherapy and targeted therapy drugs can kill cancer cells with minimal side effects. All anticancer agents work based on the killing of cancer cells. Numerous studies are ongoing to kill cancer cells more effectively without increasing side effects to normal tissues. The combination modalities with low toxic agents are interesting for this aim. Curcumin is one of the most common herbal agents that has shown several anticancer properties. It can regulate immune system responses against cancer. Furthermore, curcumin has been shown to potentiate cell death signalling pathways and attenuate survival signalling pathways in cancer cells. The knowledge of how curcumin induces cell death in cancers can improve therapeutic efficiency. In this review, the regulatory effects of curcumin on different cell death mechanisms and their signalling pathways will be discussed. Furthermore, we explain how curcumin may potentiate the anticancer effects of other drugs or radiotherapy through modulation of apoptosis, mitotic catastrophe, senescence, autophagy and ferroptosis.