CD8A and cancer: On the one hand, TEXs can promote cancer cell growth and invasion, expression of immunosuppressive molecules like PD-L1 and TGF-β, inhibition of CD8+ T cell activation and proliferation, etc. TEXs, on the other hand, express multiple MHC I molecules and markers of the tumor, like heat shock proteins (HSPs) engaged in antigen presentation and T cell stimulation, and are able to induce antitumor responses that are dependent on CD8+ T cells in vitro and in vivo.