Publications by authors named "Diane Begemann"

Understanding the mechanisms underlying resistance is critical to improving therapeutic outcomes in patients with metastatic castration-resistant prostate cancer. Previous work showed that dynamic interconversions between epithelial-mesenchymal transition to mesenchymal-epithelial transition defines the phenotypic landscape of prostate tumors, as a potential driver of the emergence of therapeutic resistance. In this study, we use in vitro and in vivo preclinical MDA PCa patient-derived xenograft models of resistant human prostate cancer to determine molecular mechanisms of cross-resistance between antiandrogen therapy and taxane chemotherapy, underlying the therapeutically resistant phenotype.

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Background: Disruption of the phenotypic landscape via epithelial-mesenchymal transition (EMT) enables prostate cancer cells to metastasize and acquire therapeutic resistance. Our previous studies demonstrated that cabazitaxel (CBZ) (second-generation Food and Drug Administration-approved taxane chemotherapy), used for the treatment of castration-resistant prostate cancer (CRPC), causes reversal of EMT to mesenchymal-epithelial transition (MET) and reduces expression of kinesin motor protein KIFC1 (HSET). The present study examined the effect of sequencing CBZ chemotherapy mediated MET on prostate tumor redifferentiation overcoming therapeutic resistance in models of advanced prostate cancer.

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Background: Prostate cancer progression is navigated by the androgen receptor (AR) and transforming-growth factor-β (TGF-β) signaling. We previously demonstrated that aberrant TGF-β signaling accelerates prostate tumor progression in a transgenic mouse model of prostate cancer via effects on epithelial-mesenchymal transition (EMT), driving castration-resistant prostate cancer (CRPC).

Methods: This study examined the antitumor effect of the combination of TGF-β receptor I (TβRI) inhibitor, galunisertib, and FDA-approved antiandrogen enzalutamide, in our pre-clinical model.

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Prostate cancer is a widespread problem among men, with >160 000 new cases in 2017 alone. Androgen deprivation therapy is commonly used in prostate cancer treatment to block androgens required for cancer growth, but disease relapse after androgen deprivation therapy is both common and severe. Changes in androgen receptor signaling from androgen deprivation therapy have been linked to therapeutic resistance and tumor progression.

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The androgen receptor (AR) plays a critical role as a driver of castration-resistant prostate cancer (CRPC). Our previous studies demonstrated that disruption of transforming growth factor-β (TGF-β) signaling via introduction of dominant-negative transforming growth factor-β type II receptor (DNTGFβRII) in the prostate epithelium of transgenic adenocarcinoma of the prostate mice accelerated tumor. This study investigated the consequences of disrupted TGF-β signaling on prostate tumor growth under conditions of castration-induced androgen deprivation in the preclinical model of DNTGFβRII.

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