Therapeutic Targeting of Histone Lysine Demethylase KDM4B Blocks the Growth of Castration-Resistant Prostate Cancer

Abstract Background: Accumulating evidence points to epigenetic mechanisms as essential in tumorigenesis. Treatment that targets epigenetic regulators is becoming an attractive strategy for cancer therapy. The role of epigenetic therapy in prostate cancer (PCa) remains elusive. Previously we demonstrated a correlation of levels of histone lysine demethylase KDM4B with the appearance of castration resistant prostate cancer (CRPC) and identified a small molecular inhibitor of KDM4B, B3. In this study, we aim to define the role of KDM4B in promoting PCa progression and test the efficacy of B3 using clinically relevant PCa models. Methods: KDM4B was overexpressed in LNCaP cells or knocked down (KD) in 22Rv1 cells. The specificity of B3 was determined in vitro using recombinant KDM proteins and in vivo using 22Rv1 cell lysates. The efficacy of B3 monotherapy or in combination with androgen receptor (AR) antagonist enzalutamide or the mTOR inhibitor rapamycin was tested using xenograft models in castrated mice. Comparative transcriptomic analysis was performed on KDM4B KD and B3-treated 22Rv1 cells to determine the on-target (KDM4B-dependent) and off-target (non-KDM4B-associated) effects of B3.Results: Overexpression of KDM4B in LNCaP cells enhanced its tumorigenicity whereas knockdown of KDM4B in 22Rv1 cells reduced tumor growth in castrated mice. B3 suppressed the growth of both 22Rv1 and VCaP xenografts and sensitized 22Rv1 cells to enzalutamide inhibition. B3 also inhibited 22Rv1 tumor growth synergistically with rapamycin that resulted in cell apoptosis. Mechanistically, B3 inhibited expression of AR-V7 and genes involved in epithelial-to-mesenchymal transition. DNA replication stress marker gH2A.X was upregulated by B3, which is further increased when combined with rapamycin. Based on transcriptomic and biochemical analyses, B3 inhibits both H3K9me3 and H3K27me3 demethylase activity, which is believed to underlie its anti-tumor action. Conclusions: Our studies establish KDM4B as a potent target for CRPC and B3 as a potential therapeutic agent. B3 as monotherapy or in combination with other anti-PCa therapeutics offers proof of principle for the clinical translation of epigenetic therapy targeting KDMSs for CRPC patients.

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Therapeutic Targeting of Histone Lysine Demethylase KDM4B Blocks the Growth of Castration-resistant Prostate Cancer

10.21203/rs.3.rs-957516/v1 ◽

2021 ◽

Author(s):

Lingling Duan ◽

Yu-An Chen ◽

Yanping Liang ◽

Zhenhua Chen ◽

Jun Lu ◽

...

Keyword(s):

Prostate Cancer ◽

Tumor Growth ◽

Epigenetic Therapy ◽

Castration Resistant Prostate Cancer ◽

Lncap Cells ◽

Castration Resistant ◽

Histone Lysine ◽

Histone Lysine Demethylase ◽

Lysine Demethylase

Abstract Background: Accumulating evidence points to epigenetic mechanisms as essential in tumorigenesis. Treatment that targets epigenetic regulators is becoming an attractive strategy for cancer therapy. The role of epigenetic therapy in prostate cancer (PCa) remains elusive. Previously we demonstrated a correlation of levels of histone lysine demethylase KDM4B with the appearance of castration resistant prostate cancer (CRPC) and identified a small molecular inhibitor of KDM4B, B3. In this study, we aim to define the role of KDM4B in promoting PCa progression and test the efficacy of B3 using clinically relevant PCa models. Methods: KDM4B was overexpressed in LNCaP cells or knocked down (KD) in 22Rv1 cells. The specificity of B3 was determined in vitro using recombinant KDM proteins and in vivo using 22Rv1 cell lysates. The efficacy of B3 monotherapy or in combination with androgen receptor (AR) antagonist enzalutamide or the mTOR inhibitor rapamycin was tested using xenograft models in castrated mice. Comparative transcriptomic analysis was performed on KDM4B KD and B3-treated 22Rv1 cells to determine the on-target (KDM4B-dependent) and off-target (non-KDM4B-associated) effects of B3.Results: Overexpression of KDM4B in LNCaP cells enhanced its tumorigenicity whereas knockdown of KDM4B in 22Rv1 cells reduced tumor growth in castrated mice. B3 suppressed the growth of both 22Rv1 and VCaP xenografts and sensitized 22Rv1 cells to enzalutamide inhibition. B3 also inhibited 22Rv1 tumor growth synergistically with rapamycin that resulted in cell apoptosis. Mechanistically, B3 inhibited expression of AR-V7 and genes involved in epithelial-to-mesenchymal transition. DNA replication stress marker γH2A.X was upregulated by B3, which is further increased when combined with rapamycin. Based on transcriptomic and biochemical analyses, B3 inhibits both H3K9me3 and H3K27me3 demethylase activity, which is believed to underlie its anti-tumor action.Conclusions: Our studies establish KDM4B as a potent target for CRPC and B3 as a potential therapeutic agent. B3 as monotherapy or in combination with other anti-PCa therapeutics offers proof of principle for the clinical translation of epigenetic therapy targeting KDMSs for CRPC patients.

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The emerging role of noncoding RNA in prostate cancer progression and its implication on diagnosis and treatment

10.31234/osf.io/4u2sd ◽

2020 ◽

Author(s):

Lungwani Muungo

Keyword(s):

Prostate Cancer ◽

Tumor Growth ◽

Cancer Progression ◽

Noncoding Rna ◽

Castration Resistant Prostate Cancer ◽

Systematic Analysis ◽

Castration Resistant ◽

Insight Into ◽

Generation Sequencing

Recent transcriptome studies using next-generation sequencing have detected aberrant changes in the expression of noncodingRNAs (ncRNAs) associated with cancer. For prostate cancer, the expression levels of ncRNAs including microRNAsand long noncoding RNAs are strongly associated with diagnosis, carcinogenesis and tumor growth. Moreover, androgenand its cognate receptor, androgen receptor (AR), regulate various signaling pathways for prostate tumor growth. In addition,progression to lethal castration-resistant prostate cancer (CRPC) is also owing to AR function. Systematic analysis ofAR-binding sites and their regulated transcripts revealed that many ncRNAs are widely regulated at the transcriptionallevel. Thus, recent studies provide new insight into the complicated molecular mechanism of prostate cancer progression.This review focused on the role of various ncRNAs in prostate cancer and the association between their expression andCRPC.

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The role of microbiota in driving castration-resistant prostate cancer

10.26226/morressier.5f69edb69b74b699bf38c5cf ◽

2020 ◽

Author(s):

Arianna Calcinotto

Keyword(s):

Prostate Cancer ◽

Castration Resistant Prostate Cancer ◽

Castration Resistant

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AR Copy Number and AR Signaling-directed Therapies in Castrationresistant Prostate Cancer

Current Cancer Drug Targets ◽

10.2174/1568009617666171122145852 ◽

2018 ◽

Vol 18 (9) ◽

pp. 869-876

Author(s):

Samanta Salvi ◽

Vincenza Conteduca ◽

Cristian Lolli ◽

Sara Testoni ◽

Valentina Casadio ◽

...

Keyword(s):

Prostate Cancer ◽

Copy Number ◽

Clinical Trial Design ◽

Complete Information ◽

Castration Resistant Prostate Cancer ◽

Castration Resistant ◽

Anti Cancer ◽

Hormone Sensitive ◽

Predictive And Prognostic Biomarker

Background: Adaptive upregulation of Androgen Receptor (AR) is the most common event involved in the progression from hormone sensitive to Castration-Resistant Prostate Cancer (CRPC). AR signaling remains the main target of new AR signalling-directed therapies such as abiraterone and enzalutamide in CRPC patients. Objective: In this review, we discuss general mechanisms of resistance to AR-targeted therapies, with a focus on the role of AR Copy Number (CN). We reported methods and clinical applications of AR CN evaluation in tissue and liquid biopsy, thus to have a complete information regarding its role as predictive and prognostic biomarker. Conclusion: Outcomes of CRPC patients are reported to be highly variable as the consequence of tumor heterogeneity. AR CN could contribute to patient selection and tumor monitoring in CRPC treated with new anti-cancer treatment as abiraterone and enzalutamide. Further studies to investigate AR CN effect to these agents and its potential combination with other prognostic or predictive clinical factors are necessary in the context of harmonized clinical trial design.

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Interplay Between SOX9, Wnt/β-Catenin and Androgen Receptor Signaling in Castration-Resistant Prostate Cancer

International Journal of Molecular Sciences ◽

10.3390/ijms20092066 ◽

2019 ◽

Vol 20 (9) ◽

pp. 2066 ◽

Cited By ~ 12

Author(s):

Namrata Khurana ◽

Suresh C. Sikka

Keyword(s):

Prostate Cancer ◽

Androgen Receptor ◽

Signaling Pathways ◽

Critical Role ◽

Castration Resistant Prostate Cancer ◽

Form Complex ◽

Androgen Receptor Signaling ◽

Castration Resistant ◽

Signaling Axis

Androgen receptor (AR) signaling plays a key role not only in the initiation of prostate cancer (PCa) but also in its transition to aggressive and invasive castration-resistant prostate cancer (CRPC). However, the crosstalk of AR with other signaling pathways contributes significantly to the emergence and growth of CRPC. Wnt/β-catenin signaling facilitates ductal morphogenesis in fetal prostate and its anomalous expression has been linked with PCa. β-catenin has also been reported to form complex with AR and thus augment AR signaling in PCa. The transcription factor SOX9 has been shown to be the driving force of aggressive and invasive PCa cells and regulate AR expression in PCa cells. Furthermore, SOX9 has also been shown to propel PCa by the reactivation of Wnt/β-catenin signaling. In this review, we discuss the critical role of SOX9/AR/Wnt/β-catenin signaling axis in the development and progression of CRPC. The phytochemicals like sulforaphane and curcumin that can concurrently target SOX9, AR and Wnt/β-catenin signaling pathways in PCa may thus be beneficial in the chemoprevention of PCa.

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