The tumor immune microenvironment in gastroenteropancreatic neuroendocrine neoplasms

• Published in: Biochimica et biophysica acta. Reviews on cancer Vol. 1872; no. 2; p. 188311
• Main Authors: Zhang, Wu-Hu, Wang, Wen-Quan, Gao, He-Li, Yu, Xian-Jun, Liu, Liang
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.12.2019
• Subjects: Biomarkers; Gastroenteropancreatic neuroendocrine neoplasms; Immune checkpoint inhibitors; Immunotherapy; Tumor immune microenvironment; Biomarkers; Gastroenteropancreatic neuroendocrine neoplasms; Tumor immune microenvironment; Immune checkpoint inhibitors; Immunotherapy
• ISSN: 0304-419X; 1879-2561
• DOI: 10.1016/j.bbcan.2019.188311

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are a group of rare tumors that are increasing in prevalence. The complex tumor immune microenvironment (TIME) plays an important role in tumor development and the response to immunotherapy but is poorly understood. In this review, the components of the TIME are described in detail, including discussion about infiltrating immune cells, the immune checkpoint system, the cytokine and chemokine milieu, and immunomodulatory factors. Moreover, a comparison between TIMEs among different types of GEP-NENs and the interplay among the TIME, tumor cells, and the stromal microenvironment is described. Novel treatment options for GEP-NENs and potential biomarkers for the immune response are also characterized. We provide a comprehensive generalized review of the TIME that can inform GEP-NEN treatment strategies.