TY - JOUR
T1 - A Multivalent Peptoid Conjugate Modulates Androgen Receptor Transcriptional Activity to Inhibit Therapy-resistant Prostate Cancer
AU - Habault, Justine
AU - Schneider, Jeffrey A.
AU - Ha, Susan
AU - Ruoff, Rachel
AU - Pereira, Luiza D.
AU - Puccini, Joseph
AU - Ranieri, Michela
AU - Ayasun, Ruveyda
AU - Deng, Jiehui
AU - Kasper, Amanda C.
AU - Bar-Sagi, Dafna
AU - Wong, Kwok Kin
AU - Zoubeidi, Amina
AU - Claessens, Frank
AU - Wise, David R.
AU - Logan, Susan K.
AU - Kirshenbaum, Kent
AU - Garabedian, Michael J.
N1 - Publisher Copyright:
© 2023 American Association for Cancer Research.
PY - 2023/10/1
Y1 - 2023/10/1
N2 - Prostate cancers adapt to androgen receptor (AR) pathway inhibitors and progress to castration resistance due to ongoing AR expression and function. To counter this, we developed a new approach to modulate the AR and inhibit castration-resistant prostate cancer (CRPC) using multivalent peptoid conjugates (MPC) that contain multiple copies of the AR-targeting ligand ethisterone attached to a peptidomimetic scaffold. Here, we investigated the antitumor effects of compound MPC309, a trivalent display of ethisterone conjugated to a peptoid oligomer backbone that binds to the AR with nanomolar affinity. MPC309 exhibited potent antiproliferative effects on various enzalutamide-resistant prostate cancer models, including those with AR splice variants, ligand-binding mutations, and noncanonical AR gene expression programs, as well as mouse prostate organoids harboring defined genetic alterations that mimic lethal human prostate cancer subtypes. MPC309 is taken up by cells through macropinocytosis, an endocytic process more prevalent in cancer cells than in normal ones, thus providing an opportunity to target tumors selectively. MPC309 triggers a distinct AR transcriptome compared with DHT and enzalutamide, a clinically used antiandrogen. Specifically, MPC309 enhances the expression of differentiation genes while reducing the expression of genes needed for cell division and metabolism. Mechanistically, MPC309 increases AR chromatin occupancy and alters AR interactions with coregulatory proteins in a pattern distinct from DHT. In xenograft studies, MPC309 produced significantly greater tumor suppression than enzalutamide. Altogether, MPC309 represents a promising new AR modulator that can combat resistant disease by promoting an AR antiproliferative gene expression program.
AB - Prostate cancers adapt to androgen receptor (AR) pathway inhibitors and progress to castration resistance due to ongoing AR expression and function. To counter this, we developed a new approach to modulate the AR and inhibit castration-resistant prostate cancer (CRPC) using multivalent peptoid conjugates (MPC) that contain multiple copies of the AR-targeting ligand ethisterone attached to a peptidomimetic scaffold. Here, we investigated the antitumor effects of compound MPC309, a trivalent display of ethisterone conjugated to a peptoid oligomer backbone that binds to the AR with nanomolar affinity. MPC309 exhibited potent antiproliferative effects on various enzalutamide-resistant prostate cancer models, including those with AR splice variants, ligand-binding mutations, and noncanonical AR gene expression programs, as well as mouse prostate organoids harboring defined genetic alterations that mimic lethal human prostate cancer subtypes. MPC309 is taken up by cells through macropinocytosis, an endocytic process more prevalent in cancer cells than in normal ones, thus providing an opportunity to target tumors selectively. MPC309 triggers a distinct AR transcriptome compared with DHT and enzalutamide, a clinically used antiandrogen. Specifically, MPC309 enhances the expression of differentiation genes while reducing the expression of genes needed for cell division and metabolism. Mechanistically, MPC309 increases AR chromatin occupancy and alters AR interactions with coregulatory proteins in a pattern distinct from DHT. In xenograft studies, MPC309 produced significantly greater tumor suppression than enzalutamide. Altogether, MPC309 represents a promising new AR modulator that can combat resistant disease by promoting an AR antiproliferative gene expression program.
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U2 - 10.1158/1535-7163.MCT-23-0196
DO - 10.1158/1535-7163.MCT-23-0196
M3 - Article
C2 - 37486978
AN - SCOPUS:85174642501
SN - 1535-7163
VL - 22
SP - 1166
EP - 1181
JO - Molecular Cancer Therapeutics
JF - Molecular Cancer Therapeutics
IS - 10
ER -