Immunotherapy-based novel nanoparticles in the treatment of gastrointestinal cancer: Trends and challenges

Figure 1 Tumor vaccine and tumor immunotherapy. Total tumor RNA was extracted and mixed with an immune adjuvant to formulate tumor vaccine. Tumor antigen was expressed and presented or cross-presented to Th and Tc cells by antigen presenting cells in lymph node to generate specific anti-tumor response. Citation: Zhang Y, Xie F, Yin Y, Zhang Q, Jin H, Wu Y, Pang L, Li J, Gao J. Immunotherapy of Tumor RNA-Loaded Lipid Nanoparticles Against Hepatocellular Carcinoma. Int J Nanomedicine 2021; 16: 1553-1564. Copyright ©The Authors 2011. Published by Dove Medical Press. The authors have obtained the permission for figure using from the Dove Medical Press Publishing Group (Supplementary material). Ab: Antibody; Ag: Antigen; BCR: B cell receptor; TCR: T-cell receptor; MHC: Major histocompatibility complex; PRR: Pattern recognition receptors; Th1/2: T helper type 1/2; CTL: Cytotoxic T-lymphocyte; CTLA4: Cytotoxic T-lymphocyte-associated protein 4; Treg: Regulatory T cell; DC: Dendritic cell; NK: Natural killer cell; MDSC: Mmyeloid-derived suppressor cell; ADCC: Antibody-dependent cellular cytotoxicity; CDC: Complement-dependent cytotoxicity; SIRPα: Signal regulatory protein α; LILRB1: Leukocyte immunoglobulin like receptor B1; TIM-3: T-cell immunoglobulin and mucin domain-3; PD1: Programmed cell death protein 1; PD-L1: Programmed death-ligand 1; IL-2: Interleukin-2; IFNγ: Interferon γ; KIR: Killer cell immunoglobulin-like receptor; NKG2D: Natural killer group 2 member D.

Figure 2 Altering an immunosuppressive tumor microenvironment into a pro-inflammatory microenvironment with the use of toll-like receptor agonists. Citation: Haegebaert RMS, Kempers M, Ceelen W, Lentacker I, Remaut K. Nanoparticle mediated targeting of toll-like receptors to treat colorectal cancer. Eur J Pharm Biopharm 2022; 172: 16-30. Copyright ©The Authors 2022. Published by Elsevier. The authors have obtained the permission for figure using from the Elsevier Publishing Group (Supplementary material). Treg: T regulatory cell; MDSCs: Myeloid-derived suppressor cells; CAF: Cancer-associated fibroblast; Th1: T-helper 1; CD8⁺ T cells: Cytotoxic T cells; NK: Natural killer; TLR: Toll-like receptor.