Summary:
Autophagy is a catabolic process in which cellular components are degraded in
the lysosome. Macroautophagy, the most known type of autophagy, is
characterized by the formation of autophagosomes. Their products are recycled
to be used in cell biosynthetic pathways. Under normal conditions autophagy is
maintained in a basal rate eliminating long-lived and/or damaged proteins and
organelles. Under stress conditions, like nutrient or growth factor deprivation
and oxidative stress, autophagy is induced as a cytoprotective mechanism to
ensure cell survival. Autophagy is regulated by various factors, through
different signaling pathways. Autophagy also participates in physiological
functions regulation, such as development, cellular differentiation and
metabolism. Defective autophagy is implicated in a variety of pathologies,
including neurodegeneration, diabetes and cancer. The role of autophagy in
human tumorigenesis is a double-sword and depends from cancer stage and tumor
microenvironment. Autophagy manipulation, either its inhibition or promotion
which could lead even to cell death with autophagy, is used in cancer therapy
combinated with other anticancer therapies, such as chemotherapy and
radiotherapy. Complete understanding of autophagy mechanisms regulation and the
exact role of autophagy in cancer would allow its secure envolvement in
anticancer therapies in order to increase their effectiveness.
Keywords:
Autophagy, Autophagosomes, Anticancer therapy, Tumorigenesis, mTOR