Interplay between apoptosis and autophagy, a challenging puzzle: New perspectives on antitumor chemotherapies

Autophagy is a mechanism of protection against various forms of human diseases, such as cancer, in which autophagy seems to have an extremely complex role. In cancer, there is evidence that autophagy may be oncogenic in some contexts, whereas in others it clearly contributes to tumor suppression. In addition, studies have demonstrated the existence of a complex relationship between autophagy and cell death, determining whether a cell will live or die in response to anticancer therapies. Nevertheless, we still need to complete the autophagy-apoptosis puzzle in the tumor context to better address appropriate chemotherapy protocols with autophagy modulators. Generally, tumor cell resistance to anticancer induced-apoptosis can be overcome by autophagy inhibition. However, when an extensive autophagic stimulus is activated, autophagic cell death is observed. In this review, we discuss some details of autophagy and its relationship with tumor progression or suppression, as well as role of autophagy-apoptosis in cancer treatments.