AZD2014, an Inhibitor of mTORC1 and mTORC2, Is Highly Effective in ER+ Breast Cancer When Administered Using...

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• The mechanistic target of rapamycin (mTOR) pathway regulates crucial cellular functions like growth and proliferation.
• mTOR functions via two distinct complexes: mTORC1 and mTORC2.
• Current mTOR inhibitors (rapalogs) primarily target mTORC1 and show efficacy in ER(+) breast cancer when combined with endocrine therapy.

Purpose of the Study:

• To evaluate the efficacy of AZD2014, a novel dual mTORC1/mTORC2 inhibitor, in preclinical models of breast cancer.
• To assess AZD2014's activity in models with acquired resistance to hormonal therapy and rapalogs.
• To investigate the potential of AZD2014 in combination with endocrine therapy.

Main Methods:

• In vitro assessment of AZD2014's antiproliferative effects across various breast cancer cell lines.
• In vivo studies using xenograft and primary explant models to evaluate tumor growth inhibition.
• Combination studies with fulvestrant using continuous and intermittent dosing schedules.
• Analysis of mTORC1 and mTORC2 substrate modulation.

Main Results:

• AZD2014 demonstrated broad antiproliferative activity against multiple cell lines, including those resistant to hormonal therapy and rapalogs.
• Dose-dependent tumor growth inhibition was observed in vivo across various preclinical models.
• Antitumor activity correlated with the inhibition of both mTORC1 and mTORC2 pathway signaling.
• Combination of AZD2014 with fulvestrant resulted in tumor regressions, irrespective of dosing schedule.

Conclusions:

• AZD2014 exhibits significant preclinical antitumor activity by inhibiting both mTORC1 and mTORC2.
• Its efficacy in resistant models and potential for intermittent dosing make it a promising candidate for combination therapy with endocrine agents.
• AZD2014 warrants further clinical investigation, particularly in combination regimens for breast cancer treatment.