Macrophage, NK cell, cancer cell, platelet, and mesenchymal stem cell membrane-coated nanoparticles have tumor targeting capabilities. the review, we summarize the latest researches of biomimetic CMCNs for cancer immunotherapy, outline the existing specific cancer immune therapies, explore the unique functions and molecular mechanisms of various Exendin-4 Acetate cell Exendin-4 Acetate membrane-coated nanoparticles, and analyze the challenges which CMCNs face in clinical translation. causes greater toxic side-effects. Engineering modified nanoparticles can improve the distribution of nanoparticles and back into the patient to eliminate and control cancers, including non-tumor specific cells (NK cells, DCs, cytokine-induced killer cells, lymphocyte activated killer cells, tumor infiltrating lymphocyte), and tumor specific cells (CAR-T cells, T cell receptor-T cells, CAR-NK cells). The tumor specific cells have been modified to have stronger tumor antigen specificity and exert a stronger tumor recognition and killing effect. FDA has approved CAR-T drugs including Kymriah? and Yescarta?, which are used to treat relapsed or refractory adult large B-cell lymphoma and recurrent or refractory B-cell acute lymphoblastic leukemia39. However, compared with hematomas, the efficacy of CAR-T is quite restricted in solid tumors because of tumor antigens heterogeneity, insufficient infiltration, and the tumor immunosuppressive microenvironment. So far, improvements of CAR-T cells have been made in respect of cancer heterogeneity, including the construction of CAR-T cells expressing multiple CARs, the combined applications of multiple CAR-T cells40, and the applications of CD133CAR-T cells targeting cancer stem cells that dominate the heterogeneity of solid tumors41. Intratumoral injection or combining with oncolytic virus that up-regulates the expression of chemokines in tumors was investigated for better CAR-T infiltration42. Aiming at the tumor immunosuppressive microenvironment, some studies focused on regulating the metabolism of CAR-T cells43 and cytokine expression44 to improve cell activity in harsh environments and enhance its tumor-killing activity. There are also researches on extracellular matrix (ECM) and cancer-associated fibroblasts in the tumor immunosuppressive microenvironment. Fibroblast activation protein-specific CAR-T cells45 showed great antitumor Exendin-4 Acetate potential by killing immunosuppressive cells and degrading ECM. Although the various efforts made against solid tumors, CAR-T therapy still faces great challenges. CAR-T therapy combining with the complementary ICB therapy or cytokines that can effectively alleviate the tumor immunosuppressive microenvironment, may achieve better anti-cancer effects. 2.1.3. Cytokine immunotherapy Cytokines are messenger molecules that are secreted in respond to cellular stress (such as infection, inflammation, cancer occurrence, etc.), and further coordinate the interaction and function of immune cells. Interleukin-2 (IL-2), interferon (IFN) and other cytokines enhance the anti-cancer immune effect by stimulating the maturation of DCs and enhancing the cytotoxicity of T cells46. In clinical practice, cytokine immunotherapy has played an effective anti-cancer effect, Exendin-4 Acetate but it can cause nonnegligible toxicity, which limits its application as a monotherapy. At present, many researchers have conducted attempts to couple cytokines and adoptive T-cell immunotherapy47, one of which coupled the reduction-sensitive IL-2 nanogel to the surface Mouse monoclonal to CK7 of the adoptive T-cell membrane. The lethal dose of IL-2 can be safely released at the tumor site during systemic administration, further effectively stimulated the adoptive T-cell in the tumor environment and enhanced its tumor killing effect. This study provides new insights into the combinational therapy for anti-cancer treatment. 2.1.4. Immune checkpoint blockade inhibitors Immune checkpoints are a couple of molecules from co-suppress signal pathways, which are expressed in healthy tissue to maintain the body’s immune balance. However, when cancers occur, cancer cells and immunosuppressive cells upregulate immune checkpoints expression to avoid immune surveillance. Blocking the co-inhibition signal pathway reactivates the anti-cancer immune Exendin-4 Acetate response48. Extensive researches have shown multiple ICB targets, including indoleamine 2,3-dioxygenase (IDO), cytotoxic T lymphocyte-associated molecule-4 (CTLA-4)49, programmed cell death receptor-1(PD-1)programmed cell death ligand-1(PD-L1)50, etc. Blocking the above receptor/ligand-mediated co-inhibition signaling pathways by specific antibodies has achieved good clinical anti-cancer effects51, 52, 53. However, in clinical applications, compared with the 80% effective rate for lymphoma, the effective rate for solid tumors drop to 10%C30%54. The low response rate has become a tough barrier for ICB inhibitors in the treatment of the most cancers, which may be related to the sophisticated immunosuppressive mechanisms in TME. Regarding these issues, development of new tumor co-suppressive molecules (such as Siglec-15)55, application of two or more ICB inhibitors56, or combination of ICB inhibitors with CAR-T or other immunotherapies to achieve a supplementary effect, can solve the immune escaping of cancer cells.