Type 2 Diabetes in Neuroendocrine Tumors: Are Biguanides and Statins Part of the Solution?

Area of Science:

• Oncology
• Pharmacology
• Molecular Biology

Background:

• Biguanides and statins demonstrate potential anti-cancer properties across various tumor types.
• The precise mechanisms underlying the anti-tumorigenic effects of biguanides and statins remain incompletely understood, particularly in neuroendocrine tumors (NETs).

Purpose of the Study:

• To investigate the relationship between metabolic syndrome and prognostic variables in patients with lung carcinoids (LCs) and gastroenteropancreatic NETs (GEP-NETs).
• To evaluate the in vitro antitumor effects of biguanides and statins on NET cell lines, focusing on proliferation, migration, secretion, and molecular pathways.

Main Methods:

• Analysis of clinical data from two NET patient cohorts (LCs, n=81; GEP-NETs, n=100) concerning metabolic syndrome and tumor characteristics.
• In vitro experiments using BON1/QGP1 cell cultures to assess the impact of biguanides (metformin, phenformin) and statins (simvastatin, atorvastatin) on cell proliferation, migration, apoptosis, and gene expression.

Main Results:

• Type 2 diabetes was associated with increased pleura invasion in LCs and a trend towards increased tumor diameter in GEP-NETs.
• Biguanides reduced NET cell proliferation and serotonin secretion; phenformin induced apoptosis.
• Statins exhibited variable effects on proliferation depending on the specific drug and cell type; simvastatin and atorvastatin reduced proliferation in BON1 cells, while all tested statins reduced proliferation in QGP1 cells. Simvastatin also induced apoptosis in QGP1 cells.

Conclusions:

• Biguanides and statins exhibit a notable inhibitory effect on NET cell aggressiveness.
• These findings suggest a potential therapeutic role for biguanides and statins in the management of neuroendocrine tumors, meriting further investigation.