A potential significance of controlled autophagy in the enhancement of oncolytic virotherapy.
Oncolytic virotherapy is a promising approach for the treatment of cancer patients, although more studies is required to increase its clinical efficiency. It is important to explore new strategies to enhance oncolytic properties of viruses. Many viruses have developed a variety of mechanisms that either inhibit the autophagic degradation, or subverts the autophagy process for their own benefit. The aim of this study was to explore the role of autophagy in replication of some oncolytic viruses. Members of non-pathogenic enteroviruses and paramyxoviruses have been chosen for the study. We found that only some of the viruses tested were capable of inducing the autophagy in cancer cells. The induction of autophagy by Torin-2, a direct inhibitor of mTOR was capable of promoting the oncolysis by paramyxovirus Sendai, while some other viruses exploited induced autophagy to prolong virus production by suppressing premature cell death. We suggest that a deliberate modulation of the autophagy may by helpful for the enhancement of oncolytic effects representing a supplemental antitumor strategy.