Inhibition of esophageal cancer growth through the suppression of PI3K/AKT/mTOR signaling pathway

Area of Science:

• Oncology
• Molecular Biology
• Cancer Therapeutics

Background:

• The phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway is frequently dysregulated in various cancers.
• AKT allosteric inhibitor MK2206 and dual PI3K/mTOR inhibitor BEZ235 are investigational drugs targeting this pathway.

Purpose of the Study:

• To investigate the activation status of the PI3K/AKT/mTOR pathway in esophageal squamous cell carcinoma (SCC).
• To evaluate the anti-tumor efficacy of MK2206 and BEZ235, both individually and in combination, against esophageal cancer.

Main Methods:

• Utilized a carcinogen-induced animal model, human esophageal SCC cell lines, and a xenograft mouse model.
• Assessed pathway activation, cell proliferation, apoptosis, and cell-cycle progression.
• Monitored tumor growth and AKT phosphorylation in vivo.

Main Results:

• PI3K/AKT/mTOR pathway components were overexpressed and activated in esophageal SCC.
• MK2206 and BEZ235 demonstrated anti-proliferative and pro-apoptotic effects, inducing cell-cycle arrest via downstream targets.
• Combination therapy significantly inhibited tumor growth in mice by suppressing AKT phosphorylation at Thr308 and Ser473, outperforming monotherapies.

Conclusions:

• The combination of MK2206 and BEZ235 exhibits robust anti-tumor activity against esophageal SCC.
• This combination therapy holds promise for clinical application in treating esophageal squamous cell carcinoma.