Prognostic significance of tumor immune microenvironment and immunotherapy: Novel insights and future perspectives in gastric cancer

Abstract

Despite a decrease in gastric cancer incidence, the development of novel biologic agents and combined therapeutic strategies, the prognosis of gastric cancer remains poor. Recently, the introduction of modern immunotherapy, especially using immune checkpoint inhibitors, led to an improved prognosis in many cancers. The use of immunotherapy was also associated with manageable adverse event profiles and promising results in the treatment of patients with gastric cancer, especially in heavily pretreated patients. These data have led to an accelerated approval of some checkpoint inhibitors in this setting. Understanding the complex relationship between the host immune microenvironment and tumor and the immune escape phenomenon leading to cancer occurrence and progression will subsequently lead to the identification of prognostic immune markers. Furthermore, this understanding will result in the discovery of both new mechanisms for blocking tumor immunosuppressive signals and pathways to stimulate the local immune response by targeting and modulating different subsets of immune cells. Due to the molecular heterogeneity of gastric cancers associated with different clinico-biologic parameters, immune markers expression and prognosis, novel immunotherapy algorithms should be personalized and addressed to selected subsets of gastric tumors, which have been proven to elicit the best clinical responses. Future perspectives in the treatment of gastric cancer include tailored dual immunotherapies or a combination of immunotherapy with other targeted agents with synergistic antitumor effects.

Immune cell infiltration as a biomarker for the diagnosis and prognosis of digestive system cancer

“…In a pan‐cancer analysis, Chen et al discovered 4 immune types across 14 solid cancer types, including COAD, LIHC, STAD, and other system cancers. In addition, studies of the tumor immune microenvironment on colorectal cancer, esophageal cancer, pancreatic cancer, and gastric cancer have been reported. We focused on DSCs that have many similar characteristics and risk factors, systematically analyzing the immune environment and providing predictors of DSCs.…”

Chemokine receptor 4 expression is correlated with the occurrence and prognosis of gastric cancer

“…We also focused our attention on another important characteristic, tumor immune infiltration. The effect of immune infiltration cells on the prognosis of GC is still controversial [35]. In the present study, genes involved in the immune and the inflammation response were enriched in the fraction of genes showing a differential expression between the CXCR4‐H and CXCR4‐L groups.…”

Hypofractionated Irradiation Suppressed the Off-Target Mouse Hepatocarcinoma Growth by Inhibiting Myeloid-Derived Suppressor Cell-Mediated Immune Suppression

“…The immunosuppressive tumor microenvironment has been believed to be not only one of the key factors stimulating tumor progression but also a strong obstacle for efficient tumor therapy (26). MDSCs as heterogeneous immunosuppressive cells develop and expend during the tumor progression (27).…”