Mechanisms of Survival of Cytomegalovirus-Infected Tumor Cells

Abstract

Human cytomegalovirus (HCMV) DNA and proteins are often detected in malignant tumors, warranting studies of the role that HCMV plays in carcinogenesis and tumor progression. HCMV proteins were shown to regulate the key processes involved in tumorigenesis. While HCMV as an oncogenic factor just came into focus, its ability to promote tumor progression is generally recognized. The review discusses the viral factors and cell molecular pathways that affect the resistance of cancer cells to therapy. CMV inhibits apoptosis of tumor cells, that not only promotes tumor progression, but also reduces the sensitivity of cells to antitumor therapy. Autophagy was found to facilitate either cell survival or cell death in different tumor cells. In leukemia cells, HCMV induces a “protective” autophagy that suppresses apoptosis. Viral factors that mediate drug resistance and their interactions with key cell death pathways are necessary to further investigate in order to develop agents that can restore the tumor sensitivity to anticancer drugs.

Chronic Viral Infections and Cancer, Openings for Therapies and Vaccines

“…Importantly, this virus was reported to be active in the tumor tissues and latent in the normal tissues of the same patients [23][24][25]. HCMV is known to exhibit an immunomodulatory effect, impact the oncogenic pathways, and confer the survival of cancer cells [26][27][28]. Furthermore, some HCMV variants appear to be more oncogenic than others [29].…”