Beneficial Effects of Mifepristone Treatment in Patients with Breast Cancer Selected by the Progesterone Receptor Isoform Ratio: Results from the MIPRA Trial.

ABSTRACT:

Purpose

Preclinical data suggest that antiprogestins inhibit the growth of luminal breast carcinomas that express higher levels of progesterone receptor isoform A (PRA) than isoform B (PRB). Thus, we designed a presurgical window of opportunity trial to determine the therapeutic effects of mifepristone in patients with breast cancer, based on their high PRA/PRB isoform ratio (MIPRA; NCT02651844).

Patients and methods

Twenty patients with luminal breast carcinomas with PRA/PRB > 1.5 (determined by Western blots), and PR ≥ 50%, naïve from previous treatment, were included for mifepristone treatment (200 mg/day orally; 14 days). Core needle biopsies and surgical samples were formalin fixed for IHC studies, while others were snap-frozen to perform RNA sequencing (RNA-seq), prote

SUBMITTER: Elia A 

PROVIDER: S-EPMC9975668 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature