Unraveling the mysteries of MGMT: Implications for neuroendocrine tumors

Biochim Biophys Acta Rev Cancer. 2024 Nov;1879(6):189184. doi: 10.1016/j.bbcan.2024.189184. Epub 2024 Sep 18.

Abstract

Neuroendocrine tumors (NETs) are a diverse group of tumors that arise from neuroendocrine cells and are commonly found in various organs. A considerable proportion of NET patients were diagnosed at an advanced or metastatic stage. Alkylating agents are the primary treatment for NET, and O6-methylguanine methyltransferase (MGMT) remains the first-line of defense against DNA damage caused by these agents. Clinical trials have indicated that MGMT promoter methylation or its low/lacked expression can predict a favorable outcome with Temozolomide in NETs. Its status could help select NET patients who can benefit from alkylating agents. Therefore, MGMT status serves as a biomarker to guide decisions on the efficacy of Temozolomide as a personalized treatment option. Additionally, delving into the regulatory mechanisms of MGMT status can lead to the development of MGMT-targeted therapies, benefiting individuals with high levels of MGMT expression. This review aims to explore the polymorphism of MGMT regulation and summarize its clinical implications in NETs, which would help establish the role of MGMT as a biomarker and its potential as a therapeutic target in NETs. Additionally, we explore the benefits of combining Temozolomide and immunotherapy in MGMT hypermethylated subgroups. Future studies can focus on optimizing Temozolomide administration to induce specific immunomodulatory changes.

Keywords: Alkylating agents; MGMT; Neuroendocrine tumors; Temozolomide.

Publication types

  • Review

MeSH terms

  • Antineoplastic Agents, Alkylating / pharmacology
  • Antineoplastic Agents, Alkylating / therapeutic use
  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism
  • DNA Methylation
  • DNA Modification Methylases* / genetics
  • DNA Modification Methylases* / metabolism
  • DNA Repair Enzymes* / genetics
  • DNA Repair Enzymes* / metabolism
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Neuroendocrine Tumors* / drug therapy
  • Neuroendocrine Tumors* / genetics
  • Neuroendocrine Tumors* / pathology
  • Promoter Regions, Genetic
  • Temozolomide* / pharmacology
  • Temozolomide* / therapeutic use
  • Tumor Suppressor Proteins* / genetics
  • Tumor Suppressor Proteins* / metabolism

Substances

  • DNA Modification Methylases
  • DNA Repair Enzymes
  • MGMT protein, human
  • Tumor Suppressor Proteins
  • Temozolomide
  • Biomarkers, Tumor
  • Antineoplastic Agents, Alkylating