PPAR-γ Agonists As Antineoplastic Agents in Cancers with Dysregulated IGF Axis

Area of Science:

• Oncology
• Endocrinology
• Molecular Biology

Background:

• Insulin resistance and hyperinsulinemia are linked to increased cancer incidence and mortality.
• The insulin-like growth factor (IGF) axis is frequently deregulated in cancer, promoting tumor growth and therapy resistance.
• Current therapies targeting the IGF axis have limitations, necessitating novel approaches.

Purpose of the Study:

• To explore the potential of peroxisome proliferator activated receptor (PPAR)-γ agonists in cancer prevention and therapy.
• To investigate the mechanisms by which PPAR-γ agonists may impact cancer cell growth and survival.
• To evaluate the utility of PPAR-γ agonists in tumors associated with the IGF axis or hyperinsulinemia.

Main Methods:

• Review of existing literature on insulin resistance, the IGF axis, and PPAR-γ agonists in cancer.
• Analysis of the molecular pathways affected by PPAR-γ activation, including PI3K/mTOR, MAPK, and Wnt/β-catenin.
• Consideration of clinical trial outcomes for PPAR-γ agonists in cancer treatment.

Main Results:

• PPAR-γ agonists, such as thiazolidinediones (TZDs), may inhibit cancer cell growth by reducing insulin levels and modulating key IGF axis pathways.
• These agonists affect critical cancer-related pathways including PI3K/mTOR, MAPK, and GSK3-β/Wnt/β-catenin.
• Clinical trials with PPAR-γ agonists have yielded conflicting results, potentially due to patient and tumor selection criteria.

Conclusions:

• PPAR-γ agonists hold promise as preventive and therapeutic agents for tumors driven by the IGF axis or occurring in hyperinsulinemic patients.
• Combined therapies involving PPAR-γ agonists may be beneficial for IGF-driven malignancies.
• Future research should focus on selecting appropriate patient populations and tumors for PPAR-γ agonist-based therapies.