Oncolytic viruses as nanomedicines against the tumor microenvironment

Abstract

The tumor microenvironment is best described as the battleground for fighting cancer and the host immune system. Contrary to primitive beliefs that cancer growth and progression are solely dependent on cancer cells, recent studies suggest that the cancer cell mass environs also play a pivotal role. Active crosstalk between the tumor cells and their surrounding microenvironment permits their collusion to effectuate high cancer cell proliferation and metastasis. Tumors have been reported to actively recruit and alter immune cells' phenotypes and functions to either promote immune suppression or increase the tolerance towards tumor-associated antigens. Comprehending the part played by the tumor microenvironment in tumor progression and its mechanism of action paves the way for developing novel therapeutic approaches for a more personalized and efficient tumor microenvironment targeted anticancer treatment. This review elaborates on the nature and importance of the tumor microenvironment and the anti-cancer therapeutic strategies designed to target them. Furthermore, we discuss in-depth the employment of oncolytic viruses as nanomedicines for tumor microenvironment targeted anticancer therapy. This review also delineates the benefits of combining novel therapeutic approaches to existing treatment strategies to improve disease prognosis.