Figure 2.

Transforming cold tumors into hot—immunophenotypes and therapeutic strategies: Tumors are categorized into four main types based on CD3 and CD8 populations: immune cold/desert, immune altered (excluded and suppressed), and immune hot/inflamed. The illustration outlines the major immune cell types regulating each tumor landscape and proposed therapeutic approaches, including existing and investigational interventions targeting the challenges within each immunophenotype. Cell types such as TAM, MDSC, Treg, and tumor cells primarily regulate immune suppression, while DC, CD8 T, NK, B, and TH1 cells mediate anti-tumor responses. Therapeutic approaches are depicted at the bottom, and each phenotype is described in four boxes along the edges. Each therapeutic agent is utilized either alone or in combination with others to effectively tackle the challenges presented by each phenotype. Abbreviations: DC: Dendritic cell; CD8 T: Cytotoxic T cell; NK: Natural killer cell; Th1: Type 1 helper cell; TAM: Tumor-associated macrophage; MDSC: Myeloid-derived suppressor cell; Treg: Regulatory T cell; ADC: Antibody–drug conjugate; ACT: Adoptive cell transfer therapy (created with BioRender.com; accessed on 1 March 2024).