Cancer as a Dysfunctional Immune Disorder: Pro-Tumor TH1-like Immune Response and Anti-Tumor TH alpha beta Immune Response Based on the Complete Updated Framework of Host Immunological Pathways

Host immunological pathways are delicate to cope with different types of pathogens. In this article, we divide immunological pathways into two groups: Immunoglobulin G-related eradicable immunities and Immunoglobulin A-related tolerable immunities. Once immune cells encounter an antigen, they can become anergic or trigger immune reactions. Immunoglobulin D B cells and gamma delta T cells are recognizing self-antigens to become anergic. Immunoglobulin M B cells and alpha beta T cells can trigger host immune reactions. Eradicable immune responses can be divided into four groups: TH1/TH2/TH22/TH alpha beta (TH-T Helper cell groups). Tolerable immune responses can be divided into four groups: TH1-like/TH9/TH17/TH3. Four groups mean hosts can cope with four types of pathogens. Cancer is related to immune dysfunction. TH1-like immunity is pro-tumor immunity and TH alpha beta is anti-tumor immunity. TH1-like immunity is the host tolerable immunity against intracellular micro-organisms. TH alpha beta immunity is the host eradicable immunity against viruses. Cancer is also related to clonal anergy by Immunoglobulin D B cells and gamma delta T cells. Oncolytic viruses are related to the activation of anti-viral TH alpha beta immunity. M2 macrophages are related to the tolerable TH1-like immunity, and they are related to metastasis. This review is key to understanding the immune pathogenesis of cancer. We can then develop better therapeutic agents to treat cancer.