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O'Reilly, M. W.

Publications and source records attributed to O'Reilly, M. W..

2 recordsLinked to original sources

Inhibition of the androgen-activating enzyme AKR1C3 selectively decreases systemic and intra-adipose 11-oxygenated androgens in women

Androgen excess drives metabolic and reproductive complications in polycystic ovary syndrome (PCOS), affecting 10-15% of women globally. Aldo-keto reductase 1C3 (AKR1C3) converts inactive precursors from both the classic and the recently identified 11-oxygenated androgen pathways, generating testosterone and 11-ketotestosterone, respectively, which exert comparable androgen receptor activation. Both circulate in similar concentrations in premenopausal women while 11-ketotestosterone is predominant after menopause and in PCOS. Here, we show that adipocytes are a major site of AKR1C3 and androgen receptor expression, with increased expression in women and individuals with obesity. Using human female adipose tissue explants, we find a much higher activation of 11-oxygenated over classic androgens, observing a decrease in 11-oxygenated but not classic androgen activation by AKR1C3 inhibition. Correspondingly, we demonstrate that AKR1C3 inhibitor treatment in premenopausal women selectively disrupts the activation of 11-oxygenated androgens. Pharmacological targeting of AKR1C3 provides a novel strategy to alleviate systemic and intra-adipose 11-oxygenated androgen excess. One Sentence SummaryInhibition of the androgen-activating enzyme AKR1C3 results in a major decrease in 11-oxygenated but not classic androgens in women.

physiology↗

Androgen receptor interactions provide insight into steroid mediated metabolic shifts in endocrine resistant breast cancer.

PurposeAromatase Inhibitors (AI) are standard therapy for hormone receptor positive breast cancers in post-menopausal patients. Disease recurrence is common and previous studies suggest that the altered steroid environment may be a driver of resistance. Using label-free mass-spectrometry we explored the unique androgen receptor (AR) interactome that supervenes in AI resistant breast cancer and the associated hyperandrogenic environment. Experimental DesignAR expression was evaluated in a primary breast cancer tissue-microarray (n=875) with nuclear and cytoplasmic localization quantified. Liquid-chromatography tandem mass-spectrometry (LC-MS/MS) analysis was utilized to identify proteins interacting with the AR in models of AI-resistance. Validation was carried out by co-immunoprecipitation and co-localisation studies. Live-cell imaging, Seahorse MitoStress Assays and flow cytometry were used to quantify changes in mitochondria and cell metabolism arising in models of AI-resistance. ResultsUtilising digital pathology we detected that abundant cytoplasmic AR protein was associated with poor survival only in the post-menopausal cohort, and most significantly, in the therapy-refractory Luminal B subtype (p=0.0085). Models of AI-resistance and androgen excess highlight diffuse AR localisation throughout the cytoplasm and nucleus accompanied by increased mitochondrial mass and membrane potential, and increased oxidative phosphorylation and glycolysis. Exploration of the AR protein interactome identified G3BP1, SLIRP, and IGFBP5 as AR protein partners which are associated with stress, adaptive metabolic response and estrogen receptor repression. ConclusionsThe findings of this study highlight the prognostic potential of cytoplasmic AR immunoreactivity in specific breast cancer subtypes and uncover novel extra-nuclear AR protein interactions that may mediate metabolic adaptations during the development of endocrine-resistance.

cancer biology↗