CD8 + T cell dysfunction by TOX intoxication: a protumorigenic event in the tumor microenvironment

Accumulating evidence suggests the role of cellular components in achieving antitumor to protumor microenvironments. Among the various types of cells within the tumor niche, the state of CD8+ T cells apparently changes from cytotoxic T effector cells and memory T cells to exhausted CD8+ T cells. These changes in the phenotype of CD8+ T cells promote the protumor microenvironment. Recently, comprehensive experimental data delineated the role of thymocyte selection-associated high-mobility group-box protein (TOX), which regulates the transcriptional process and epigenetic remodeling, with implications in tumor and chronic viral infections. This perspective summarizes the molecular mechanisms that link CD8+ T cells, TOX, and transcriptional and epigenetic reprogramming as well as future directions for determining new avenues of cancer therapeutics.Lay abstract Cellular components within the tumor are related to the success and failure of anticancer drugs for patients. The reasons behind the changes from antitumor to protumor microenvironments are being explored to understand the immune cells. Among several types of cells, the state of CD8+ cells in the immune system apparently changes from cytotoxic immune effector cells and memory effector cells to depleted CD8+ immune cells. These changes in the phenotype of CD8+ T cells promote a favorable tumor microenvironment. This minireview summarizes the importance of CD8+ immune cells and their regulation in the development of anticancer drugs.