scholarly journals Development of a Transcriptional Amplification System Based on the PEG3 Promoter to Target Androgen Receptor-Positive and -Negative Prostate Cancer Cells

2019 ◽  
Vol 20 (1) ◽  
pp. 216
Author(s):  
Pallavi Jain ◽  
Pier-Luc Clermont ◽  
Francis Desmeules ◽  
Amina Zoubeidi ◽  
Bertrand Neveu ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Cell Lines ◽  
Cancer Management ◽  
Castration Resistant ◽  
Genetic Modifications ◽  
Amplification System ◽  
Transcriptional Amplification

Localized prostate cancer (PCa) is often curable, whereas metastatic disease treated by castration inevitably progresses toward castration-resistant PCa (CRPC). Most CRPC treatments target androgen receptor (AR) signaling. However, not all CRPC cells rely on AR activity for survival and proliferation. With advances in immunotherapy and fluid biopsies for cancer management, expression systems specific for both AR-positive and -negative PCa are required for virus-based vaccines and cell imaging. To target both AR-responsive and non-responsive cells, we developed a three-step transcriptional amplification (3STA) system based on the progression elevated gene-3 (PEG3) promoter named PEG3AP1-3STA. Notably, we report on different genetic modifications that significantly improved PEG3 promoter’s strength in PCa cells. Adenoviruses incorporating PEG3 promoter with and without transcriptional amplification systems were generated. The potential of PEG3AP1-3STA to target PCa cells was then evaluated in vitro and in vivo in androgen-responsive and non-responsive PCa cell lines. PEG3AP1-3STA was shown to be active in all PCa cell lines and not regulated by androgens, and its activity was amplified 97-fold compared to that of a non-amplified promoter. The PEG3AP1-3STA system can thus be used to target advanced AR+ and AR− cells for imaging or immunovirotherapy in advanced PCa.

scholarly journals Development of Novel Chalcone Analogs as Potential Multi-Targeted Therapies for Castration-Resistant Prostate Cancer

2021 ◽  
Author(s):  
Ola Hussein ◽  
Feras Alali ◽  
Ala‐Eddin Al Mustafa ◽  
Ashraf Khalil
Keyword(s):  
Prostate Cancer ◽  
Cell Lines ◽  
In Vivo Studies ◽  
Treatment Modalities ◽  
Castration Resistant Prostate Cancer ◽  
Castration Resistant ◽  
Biological Studies ◽  
In Silico Admet

Prostate cancer (PCa) is the second most frequently diagnosed malignancy, as well as a leading cause of cancer-related mortality in men globally. Despite the initial response to hormonal targeted therapy, the majority of patients ultimately progress to a lethal form of the disease, castration-resistant prostate cancer (CRPC). Therefore, the objective of this study was to discover and develop novel treatment modalities for CRPC. Chalcones are among the highly attractive scaffolds being investigated for their antitumor activities. A library of 26 chalcone analogs were designed, synthesized and evaluated as potential therapies for CRPC. The design was guided by in-silico ADMET prediction in which analogs with favorable drug-likeness properties were prioritized. The new compounds were synthesized, purified and characterized by extensive structural elucidation studies. The compounds in vitro cytotoxicity was evaluated against two androgen receptor (AR)-negative prostate cancer cell lines (PC3 and DU145). Among the tested compounds, pyridine containing analogs (13, 15 and 16) showed potent antiproliferative activities with IC50 values ranging between 4.32-6.47 µM against PC3 and DU145 cell lines. Detailed biological studies of the lead molecule 16 revealed that it can significantly induce apoptosis through upregulation of Bax and downregulation of Bcl-2. In addition, compound 16 potently inhibited colony formation and reduced cell migration of AR-negative PCa cell lines (PC3 and DU145). The molecular pathway analysis showed that the anticancer activity of compound 16 is associated with blocking of ERK1/2 and Akt activities. Furthermore, compound 16 inhibited angiogenesis in the chick chorioallantoic membrane (CAM) model as compared to control. Structure-activity relationship study revealed that the cytotoxicity could dramatically improve via changing the methoxylation pattern by more than 2-folds (IC50 << 2.5 μM). These results indicate that pyridine-based chalcones could serve as promising lead molecules for the treatment of CRPC; thus, further in vitro and in vivo studies are warranted.

scholarly journals Huaier Extract Inhibits Prostate Cancer Growth via Targeting AR/AR-V7 Pathway

2021 ◽  
Vol 11 ◽  
Author(s):  
Zhengfang Liu ◽  
Cheng Liu ◽  
Keqiang Yan ◽  
Jikai Liu ◽  
Zhiqing Fang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Nuclear Translocation ◽  
Mrna Levels ◽  
Castration Resistant Prostate Cancer ◽  
Castration Resistant ◽  
Specific Protease ◽  
Hormone Sensitive

The androgen receptor (AR) plays a pivotal role in prostatic carcinogenesis, and it also affects the transition from hormone sensitive prostate cancer (HSPC) to castration-resistant prostate cancer (CRPC). Particularly, the persistent activation of the androgen receptor and the appearance of androgen receptor splicing variant 7 (AR-V7), could partly explain the failure of androgen deprivation therapy (ADT). In the present study, we reported that huaier extract, derived from officinal fungi, has potent antiproliferative effects in both HSPC and CRPC cells. Mechanistically, huaier extract downregulated both full length AR (AR-FL) and AR-V7 mRNA levels via targeting the SET and MYND domain-containing protein 3 (SMYD3) signaling pathway. Huaier extract also enhanced proteasome-mediated protein degradation of AR-FL and AR-V7 by downregulating proteasome-associated deubiquitinase ubiquitin-specific protease 14 (USP14). Furthermore, huaier extract inhibited AR-FL/AR-V7 transcriptional activity and their nuclear translocation. More importantly, our data demonstrated that huaier extract could re-sensitize enzalutamide-resistant prostate cancer cells to enzalutamide treatment in vitro and in vivo models. Our work revealed that huaier extract could be effective for treatment of prostate cancer either as monotherapy or in combination with enzalutamide.

ODM-204: A novel dual inhibitor of CYP17A1 and androgen receptor for the treatment of castration-resistant prostate cancer—Preclinical data.

2015 ◽  
Vol 33 (7_suppl) ◽  
pp. 221-221
Author(s):  
Riikka Oksala ◽  
Anu Moilanen ◽  
Reetta Riikonen ◽  
Petteri Rummakko ◽  
Riikka Huhtaniemi ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Nuclear Translocation ◽  
Leuprolide Acetate ◽  
Male Rats ◽  
Castration Resistant Prostate Cancer ◽  
Dual Inhibitor ◽  
Castration Resistant

221 Background: Castration-resistant prostate cancer (CRPC) is characterized by high androgen receptor (AR) expression and persistent activation of AR signaling axis by residual tissue/tumor androgens. Targeting AR and androgen biosynthesis together may be more effective than either alone. ODM-204 is a novel, non-steroidal dual inhibitor of CYP17A1 and AR, which has shown promising results in preclinical studies. Methods: The binding affinity of ODM-204 to wild type AR was determined in rat prostate cytosolic lysates. The potency and functional activity of ODM-204 to human AR were demonstrated in cells stably transfected with the full-length AR and androgen-responsive reporter gene constructs. In addition, assays for AR nuclear translocation and the transactivation of human AR mutants T877A, W741L, and F876L were conducted. The effects of ODM-204 on the growth of androgen-dependent VCaP and LNCaP cells in vitro and subcutaneously grafted VCaP cells in vivo with the oral dose of 50 mg/kg/day were studied. The inhibition of CYP17A1 by ODM-204 was studied in vitro by using human and rat testicular microsomes and a human adrenal cortex cell line, and in vivo in male rats coadministered with luteinizing hormone releasing hormone agonist leuprolide acetate to mimic clinical situation. Results: ODM-204 is a potent inhibitor of both AR and CYP17A1. It binds to AR with a high affinity (Ki=47 nM) and selectivity and has a high potency towards CYP17A1 (IC50=22 nM). In addition, ODM-204 inhibited testosterone-mediated nuclear translocation of AR and the mutant ARs (IC50 values for AR(T877A), AR(W741L), and AR(F876L) were 95, 277, and 6 nM, respectively), and suppressed androgen-induced cell proliferation of LNCaP (IC50=170 nM) and VCaP (IC50=280 nM) cells. In a VCaP xenograft model, ODM-204 showed significant antitumor activity (tumor growth inhibition=66%). In rats, inhibitory effects of leuprolide acetate on testosterone production and androgen-sensitive organ weights were potentiated by ODM-204. Conclusions: ODM-204 is a promising new dual CYP17A1 and AR inhibitor for the treatment of CRPC. Clinical trials in patients with mCRPC will be started in early 2015.

scholarly journals PEG10 is associated with treatment-induced neuroendocrine prostate cancer

2019 ◽  
Vol 63 (1) ◽  
pp. 39-49 ◽  
Author(s):  
Soojin Kim ◽  
Daksh Thaper ◽  
Samir Bidnur ◽  
Paul Toren ◽  
Shusuke Akamatsu ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cell Lines ◽  
Resistant Cell ◽  
Dependent Manner ◽  
Castration Resistant ◽  
Neuroendocrine Prostate Cancer ◽  
Marker Status ◽  
Dose Dependent

Neuroendocrine (NE) differentiation of advanced prostate adenocarcinoma following androgen receptor (AR) axis-directed therapy is becoming increasingly recognized. Several models of this transdifferentiation provide insight into its molecular pathogenesis and have highlighted the placental gene PEG10 for further study. Using our unique model of enzalutamide resistance (ENZR) and NE differentiation, we studied PEG10/AR interplay in enzalutamide treatment-resistant cell lines 42DENZR and 42FENZR compared to LNCaP and castration-resistant 16DCRPC cells. ENZR cell lines with positive terminal NE marker status also displayed higher baseline expression of PEG10 compared to LNCaP and 16DCRPC. Antagonism of AR activity increased PEG10 expression followed by an increase in terminal NE markers. Conversely, stimulating AR activity via androgen supplementation reversed PEG10 and NE marker expression in a time and dose-dependent manner. These results were supported by human data showing that PEG10 expression is highest in NEPC and that AR-dependent gene, PSA, is negatively correlated with PEG10 in adenocarcinoma. Further, ChIP assay confirmed binding of activated AR to the PEG10 enhancer, decreasing PEG10 expression. While PEG10 did not drive NEPC, its knockdown reduced NE markers in our cell lines. Moreover, PEG10 knockdown in vitro- and in vivo-attenuated tumor growth. Overall, these observations indicate that PEG10 is an AR-repressed gene which modulates NE markers in ENZR cells and targeting PEG10 in advanced prostate cancer with NE features is a rational and viable option.

Preclinical and clinical pharmacology of EPI-7386, an androgen receptor N-terminal domain inhibitor for castration-resistant prostate cancer.

2021 ◽  
Vol 39 (6_suppl) ◽  
pp. 119-119
Author(s):  
Ronan Le Moigne ◽  
Paul Pearson ◽  
Veronique Lauriault ◽  
Nan Hyung Hong ◽  
Peter Virsik ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Clinical Trial ◽  
Androgen Receptor ◽  
Phase 1 ◽  
Castration Resistant Prostate Cancer ◽  
Castration Resistant ◽  
Pharmacokinetic Properties ◽  
Initial Cohort

119 Background: EPI-7386 is the newest of the “anitens”, a new class of compounds designed to inhibit androgen receptor activity by binding to the N-terminal domain (NTD) of the AR. Through this novel method of AR inhibition, anitens can block AR transcription even in the presence of AR ligand-binding domain (LBD) resistance mechanisms including point mutations and splice variants. Compared to the first generation aniten, EPI-506, which showed poor pharmacokinetic properties in patients, EPI-7386 is metabolically stable in vitro and in vivo. A Phase 1 clinical trial of EPI-7386 in metastatic castration-resistant prostate cancer patients failing standard of care therapies is ongoing and the pharmacokinetic properties of the drug in preclinical models as well as in the initial cohort of patients are presented. Methods: The metabolic stability of EPI-7386 was evaluated in vitro in mouse, rat, dog, monkey, and human hepatocytes. Projected PK parameters in humans were estimated from in vitro and in vivo clearance correlation (IVIVC). Induction of CYP isoforms was evaluated in human hepatocyte cultures. In patients, plasma concentrations of EPI-7386 were determined by LC-MS-MS, and 4-beta-hydroxycholesterol levels in plasma were followed over time as an indirect indicator of CYP3A induction. Results: In vitro hepatocyte studies demonstrated good metabolic stability for EPI-7386 with an in vitro half-life > 360 min. In animal PK studies, the terminal half-life of EPI-7386 was approximately 5.8 hours in mouse, 4.9 hours in rat, 13.4 hours in dog and the plasma clearance was low across species. The oral bioavailability of EPI-7386 ranged from 33–112% in mouse to > 100% in rat and dog. Using IVIVC, a predicted human clearance of 0.16–0.39 mL/min/kg was calculated for EPI-7386, which was in line with allometric scaling from animal PK parameters. Human PK profiles of different doses of EPI-7386 were simulated using predicted oral bioavailability, clearance, and volume of distribution. Cmax and AUC0–24h for the Phase 1 first-in-human study (NCT04421222) starting dose of 200 mg dose were predicted to be 6,915 ng/mL and 137,278 ng•h/mL respectively. A comparison between estimated PK parameters and actual values observed in the first patient cohort will be presented. Human hepatocyte CYP induction studies showed that EPI-7386 is not an inducer of CYP1A2 but may have the potential to induce CYP2B6 and CYP3A4. A comparison of 4-beta-hydroxy cholesterol levels measured during the phase 1 will be presented along with a comparison drawn from in vitro models. Conclusions: Pre-clinical characterization predicts that EPI-7386 has the appropriate PK and metabolic properties to afford exposure in patients at potentially efficacious levels following once-daily oral administration. PK measurements in the initial cohort of patients treated in the Phase 1 study will be presented. Clinical trial information: NCT04421222.

Androgen receptor independent acquired mechanisms of resistance to enzalutamide in castration-resistant prostate cancer.

2014 ◽  
Vol 32 (4_suppl) ◽  
pp. 129-129
Author(s):  
Russell Zelig Szmulewitz ◽  
Steve Kregel ◽  
Masis Isikbay ◽  
Yi Cai ◽  
James Lin Chen ◽  
...  
Keyword(s):  
Gene Expression ◽  
Prostate Cancer ◽  
Androgen Receptor ◽  
Cell Lines ◽  
Dna Sequences ◽  
Castration Resistant Prostate Cancer ◽  
Testosterone Levels ◽  
Castration Resistant ◽  
Stat Signaling

129 Background: Enzalutamide (MDV3100) is a second generation androgen receptor (AR) antagonist with potent activity in the treatment of castration resistant prostate cancer (CRPC). However, most patients develop resistance and progression of disease; thus there is a critical need to identify novel targetable pathways mechanistically linked to this resistance. Methods: A panel of four prostate cancer cell lines (LAPC-4, LNCaP, VCaP, and CWRR1) was created each with a different AR status that are resistant to MDV3100 by culturing cells long-term less than 6 months in the drug at pharmacologic levels. The MDV3100 resistant (MDV-R) lines were assayed for proliferation, viability, resistance to docetaxel, and tumor take of subcutaneous xenografts. AR expression and ligand binding domain (LBD) DNA sequences were analyzed. Gene expression microarray comparison of resistant and non-resistant parental cell lines was performed. Prostate-specific antigen (PSA) and testosterone levels were analyzed from conditioned media. Results: Cell lines demonstrated heterogeneous growth characteristics.In vivo studies depicted increased or unaltered tumor take and growth in castrate athymic mice. In some cell lines growth was increased in vitro when drug was withdrawn; yet this growth was inhibited by physiological testosterone levels, both in vitro and in vivo. MDV-R cells remained sensitive to docetaxel in vitro and had increased levels of ARmRNA. However, total AR protein levels were lower or unchanged than the parental lines, with evidence for increased truncated forms of AR. The AR LBD acquired no new mutations. Secreted PSA was lower in all but one MDV-R line. Gene expression analyses demonstrated strong upregulation of IGFBP3 in all MDV-R cells. Pathway analysis implicated increased IGF and JAK/STAT signaling whereas mammalian target of rapamycin (mTOR) signaling was decreased. Conclusions: Although AR-mediated pathways contribute to enzalutamide resistance, a broader approach across several cell lines suggests that there may be even a greater contribution from pleiotropic, non-AR mediated mechanisms. Such mechanisms may include IGF signaling, JAK/STAT signaling and modulation of mTOR.

Next generation N-terminal domain androgen receptor inhibitors with improved potency and metabolic stability in castration-resistant prostate cancer models.

2019 ◽  
Vol 37 (7_suppl) ◽  
pp. 220-220
Author(s):  
Ronan Le Moigne ◽  
Han-Jie Zhou ◽  
Nasrin R Mawji ◽  
C. Adriana Banuelos ◽  
Jun Wang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Metabolic Stability ◽  
Next Generation ◽  
Castration Resistant Prostate Cancer ◽  
Terminal Domain ◽  
Castration Resistant ◽  
Target Activity

220 Background: EPI-506, pro-drug of EPI-002, was a first-in-class oral small molecule from the Aniten family of compounds, which inhibit androgen receptor (AR) activity by binding to the N-terminal domain of the AR. EPI-506 was tested in a Phase 1 study in men with metastatic castration-resistant prostate cancer (mCRPC) resistant to current therapies and demonstrated a favorable tolerability profile with signs of moderate efficacy. Metabolic vulnerabilities in the chemical scaffold of EPI-506 were identified and new Aniten molecules, EPI-7170 and EPI-7245 , with improved potency, metabolic stability and pharmaceutical properties have been generated. Methods: Chemical structure activity relationships were developed in order to increase molecule potency in cellular and in vivo assays, while metabolic stability improvements were assessed in in vitro ADME assays and in animal pharmacokinetic studies. In addition, the on-target activity and selectivity was also optimized using a variety of cellular experiments. Results: Next generation Anitens demonstrated a 10-20 fold improvement on AR-driven cellular potency, with IC50’s of 0.5-1 uM when compared to 10-12 uM for EPI-002. In vitro proliferation assays demonstrated on target activity, with an IC50 ~ 2 uM in LNCaP and > 10 uM in the AR-independent cell model PC-3. EPI-7170 was also active in AR-V7-driven LNCaP95 cells. The antiproliferative effect was in alignment with the inhibitory effect on a subset of AR driven genes. In vivo activity in castrated mice bearing LNCaP tumors showed tumor growth inhibition of approximately 70%. While EPI-7170 represents a major advance, subsequent chemistry efforts led to the generation of EPI-7245 and other next generation Anitens which exhibit IC50’s < 500 nM and favorable ADME and PK profiles. Conclusions: Promising next-generation Aniten compounds have been identified. Major chemistry efforts led to the identification of several Anitens with > 10-20 fold improvements in cellular potency compared to EPI-506 which are also metabolically stable. IND-selection preclinical studies are underway on the most promising Aniten’s with an IND submission planned shortly.

An oral androgen receptor PROTAC degrader for prostate cancer.

2017 ◽  
Vol 35 (6_suppl) ◽  
pp. 273-273 ◽  
Author(s):  
Taavi K Neklesa ◽  
Lawrence B Snyder ◽  
Mark Bookbinder ◽  
Xin Chen ◽  
Andrew P Crew ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Cell Lines ◽  
Genetic Alterations ◽  
Tumor Growth Inhibition ◽  
Castration Resistant Prostate Cancer ◽  
Null Cell ◽  
Orally Bioavailable

273 Background: The Androgen Receptor (AR) remains the principal driver of castration-resistant prostate cancer during the transition from a localized to metastatic disease. Most patients initially respond to inhibitors of the AR pathway, but the response is often short-lived. The majority of patients progressing on enzalutamide or abiraterone exhibit genetic alterations in the AR locus, either in the form of amplifications or point mutations in the AR gene. Given these mechanisms of resistance, our goal is to eliminate the AR protein using the PROteolysis TArgeting Chimera (PROTAC) technology. Further, we sought to make an orally bioavailable AR PROTAC. Methods: Medicinal chemistry efforts yielded a small molecule AR PROTAC that simultaneously binds E3-ubiquitin ligase and AR, thus leading to ubiquitination and degradation of AR. This molecule has been characterized in in vitro and in vivo preclinical studies. Results: Our lead oral AR PROTAC degrades 92-98% of total AR in all cell lines tested, with 50% degradation concentration (DC50) < 1 nM. AR degradation suppresses the expression of AR-target gene PSA, inhibits cell proliferation, and induces potent apoptosis in VCaP cells. No activity is observed in AR-null cell lines, such as PC-3. While enzalutamide loses its activity in the presence of elevated androgens, AR PROTAC maintains its antiproliferative activity. Further, AR PROTAC is able to degrade all clinically relevant mutant AR proteins. A robust oral bioavailability is observed across multiple species and overall ADME properties are encouraging. Approximately 95% AR degradation is observed in AR-amplified VCaP xenografts at doses as low as 10 mg/kg. Congruent with AR degradation, a dose responsive tumor growth inhibition is observed in AR-dependent xenograft studies. Conclusions: In summary, we report the first orally bioavailable AR PROTAC that robustly degrades AR in vitro and in vivo.

scholarly journals Zeb1 and SK3 Channel Are Up-Regulated in Castration-Resistant Prostate Cancer and Promote Neuroendocrine Differentiation

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2947
Author(s):  
Fanny Bery ◽  
Mathilde Cancel ◽  
Maxime Guéguinou ◽  
Marie Potier-Cartereau ◽  
Christophe Vandier ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Epithelial To Mesenchymal Transition ◽  
Neuroendocrine Differentiation ◽  
Calcium Signal ◽  
Castration Resistant Prostate Cancer ◽  
Mesenchymal Transition ◽  
Castration Resistant

Therapeutic strategies for metastatic castration-resistant prostate cancer aim to target androgen receptor signaling. Despite initial survival benefits, treatment resistance invariably occurs, leading to lethal disease. Therapies targeting the androgen receptor can induce the emergence of a neuroendocrine phenotype and reactivate embryonic programs associated with epithelial to mesenchymal transition. We recently reported that dysregulation of the calcium signal can induce the transcription factor Zeb1, a key determinant of cell plasticity during tumor progression. The aim of this study was to determine whether the androgen receptor-targeted treatment Enzalutamide could induce dysregulation of the calcium signal involved in the progression toward epithelial to mesenchymal transition and neuroendocrine differentiation, contributing to therapeutic escape. Our results show that Zeb1 and the SK3 potassium channel are overexpressed in vivo in neuroendocrine castration-resistant prostate cancer and in vitro in LNCaP cells neurodifferentiated after Enzalutamide treatment. Moreover, the neuroendocrine phenotype is associated with a deregulation of the expression of Orai calcium channels. We showed that Zeb1 and SK3 are critical drivers of neuroendocrine differentiation. Interestingly, Ohmline, an SK3 inhibitor, can prevent the expression of Zeb1 and neuroendocrine markers induced by Enzalutamide. This study offers new perspectives to increase hormone therapy efficacy and improve clinical outcomes.

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