Pre-existing Castration-resistant Prostate Cancer-like Cells in Primary Prostate Cancer Promote Resistance to Hormonal Therapy.

Hormonal therapy targeting the androgen receptor inhibits prostate cancer (PCa), but the tumor eventually recurs as castration-resistant prostate cancer (CRPC). To understand the mechanisms by which subclones within early PCa develop into CRPC. We isolated epithelial cells from fresh human PCa cases, including primary adenocarcinoma, locally recurrent CRPC, and metastatic CRPC, and utilized single-cell RNA sequencing to identify subpopulations destined to become either CRPC-adeno or small cell neuroendocrine carcinoma (SCNC). We revealed dynamic transcriptional reprogramming that promotes disease progression among 23226 epithelial cells using single-cell RNA sequencing, and validated subset-specific progression using immunohistochemistry and large cohorts of publically available genomic data. We identified a small fraction of highly plastic CRPC-like cells in hormone-naïve early PCa and demonstrated its correlation with biochemical recurrence and distant metastasis, independent of clinical characteristics. We show that progression toward castration resistance was initiated from subtype-specific lineage plasticity and clonal expansion of pre-existing neuroendocrine and CRPC-like cells in early PCa. CRPC-like cells are present early in the development of PCa and are not exclusively the result of acquired evolutionary selection during androgen deprivation therapy. The lethal CRPC and SCNC phenotypes should be targeted earlier in the disease course of patients with PCa. Here, we report the presence of pre-existing castration-resistant prostate cancer (CRPC)-like cells in primary prostate cancer, which represents a novel castration-resistant mechanism different from the adaptation mechanism after androgen deprivation therapy (ADT). Patients whose tumors harbor increased pre-existing neuroendocrine and CRPC-like cells may become rapidly resistant to ADT and may require aggressive early intervention.

Cheng Q ，Butler W ，Zhou Y ，Zhang H ，Tang L ，Perkinson K ，Chen X ，Jiang XS ，McCall SJ ，Inman BA ，Huang J ... -  《-》

EAU guidelines on prostate cancer. Part II: Treatment of advanced, relapsing, and castration-resistant prostate cancer.

To present a summary of the 2013 version of the European Association of Urology (EAU) guidelines on the treatment of advanced, relapsing, and castration-resistant prostate cancer (CRPC). The working panel performed a literature review of the new data (2011-2013). The guidelines were updated, and levels of evidence and/or grades of recommendation were added to the text based on a systematic review of the literature that included a search of online databases and bibliographic reviews. Luteinising hormone-releasing hormone (LHRH) agonists are the standard of care in metastatic prostate cancer (PCa). LHRH antagonists decrease testosterone without any testosterone surge, and they may be associated with an oncologic benefit compared with LHRH analogues. Complete androgen blockade has a small survival benefit of about 5%. Intermittent androgen deprivation results in noninferior oncologic efficacy when compared with continuous androgen-deprivation therapy (ADT) in well-selected populations. In locally advanced and metastatic PCa, early ADT does not result in a significant survival advantage when compared with delayed ADT. Relapse after local therapy is defined by prostate-specific antigen (PSA) values >0.2 ng/ml following radical prostatectomy (RP) and >2 ng/ml above the nadir and after radiation therapy (RT). Therapy for PSA relapse after RP includes salvage RT (SRT) at PSA levels <0.5 ng/ml and SRP or cryosurgical ablation of the prostate in radiation failures. Endorectal magnetic resonance imaging and 11C-choline positron emission tomography/computed tomography (PET/CT) are of limited importance if the PSA is <1.0 ng/ml; bone scans and CT can be omitted unless PSA is >20 ng/ml. Follow-up after ADT should include analysis of PSA and testosterone levels, and screening for cardiovascular disease and metabolic syndrome. Treatment of CRPC includes sipuleucel-T, abiraterone acetate plus prednisone (AA/P), or chemotherapy with docetaxel at 75mg/m(2) every 3 wk. Cabazitaxel, AA/P, enzalutamide, and radium-223 are available for second-line treatment of CRPC following docetaxel. Zoledronic acid and denosumab can be used in men with CRPC and osseous metastases to prevent skeletal-related complications. The knowledge in the field of advanced, metastatic, and castration-resistant PCa is rapidly changing. These EAU guidelines on PCa summarise the most recent findings and put them into clinical practice. A full version is available at the EAU office or at www.uroweb.org. We present a summary of the 2013 version of the European Association of Urology guidelines on treatment of advanced, relapsing, and castration-resistant prostate cancer (CRPC). Luteinising hormone-releasing hormone (LHRH) agonists are the standard of care in metastatic prostate cancer (PCa). LHRH antagonists decrease testosterone without any testosterone surge, and they might be associated with an oncologic benefit compared with LHRH analogues. Complete androgen blockade has a small survival benefit of about 5%. Intermittent androgen deprivation results in noninferior oncologic efficacy when compared with continuous androgen-deprivation therapy (ADT) in well-selected populations. In locally advanced and metastatic PCa, early ADT does not result in a significant survival advantage when compared with delayed ADT. Relapse after local therapy is defined by prostate-specific antigen (PSA) values >0.2 ng/ml following radical prostatectomy (RP) and >2 ng/ml above the nadir and after radiation therapy. Therapy for PSA relapse after RP includes salvage radiation therapy at PSA levels <0.5 ng/ml and salvage RP or cryosurgical ablation of the prostate in radiation failures. Multiparametric magnetic resonance imaging and 11C-choline positron emission tomography/computed tomography (PET/CT) are of limited importance if the PSA is <1.0 ng/ml; bone scans, and CT can be omitted unless PSA is >20 ng/ml. Follow-up after ADT should include analysis of PSA and testosterone levels, and screening for cardiovascular disease and metabolic syndrome. Treatment of castration-resistant CRPC includes sipuleucel-T, abiraterone acetate plus prednisone (AA/P), or chemotherapy with docetaxel 75 mg/m(2) every 3 wk. Cabazitaxel, AA/P, enzalutamide, and radium-223 are available for second-line treatment of CRPC following docetaxel. Zoledronic acid and denosumab can be used in men with CRPC and osseous metastases to prevent skeletal-related complications. The guidelines reported should be adhered to in daily routine to improve the quality of care in PCa patients. As we have shown recently, guideline compliance is only in the area of 30-40%.

Heidenreich A ，Bastian PJ ，Bellmunt J ，Bolla M ，Joniau S ，van der Kwast T ，Mason M ，Matveev V ，Wiegel T ，Zattoni F ，Mottet N ，European Association of Urology ... -  《-》

Next-generation sequencing of advanced prostate cancer treated with androgen-deprivation therapy.

Androgen-deprivation therapy (ADT) is standard treatment for locally advanced or metastatic prostate cancer (PCa). Many patients develop castration resistance (castration-resistant PCa [CRPC]) after approximately 2-3 yr, with a poor prognosis. The molecular mechanisms underlying CRPC progression are unclear. To undertake quantitative tumour transcriptome profiling prior to and following ADT to identify functionally important androgen-regulated pathways or genes that may be reactivated in CRPC. RNA sequencing (RNA-seq) was performed on tumour-rich, targeted prostatic biopsies from seven patients with locally advanced or metastatic PCa before and approximately 22 wk after ADT initiation. Differentially regulated genes were identified in treatment pairs and further investigated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) on cell lines and immunohistochemistry on a separate CRPC patient cohort. Functional assays were used to determine the effect of pathway modulation on cell phenotypes. We searched for gene expression changes affecting key cell signalling pathways that may be targeted as proof of principle in a CRPC in vitro cell line model. We identified ADT-regulated signalling pathways, including the Wnt/β-catenin signalling pathway, and observed overexpression of β-catenin in a subset of CRPC by immunohistochemistry. We validated 6 of 12 (50%) pathway members by qRT-PCR on LNCaP/LNCaP-AI cell RNAs, of which 4 (67%) demonstrated expression changes consistent with RNA-seq data. We show that the tankyrase inhibitor XAV939 (which promotes β-catenin degradation) reduced androgen-independent LNCaP-AI cell line growth compared with androgen-responsive LNCaP cells via an accumulation of cell proportions in the G0/G1 phase and reduction in the S and G2/M phases. Our biopsy protocol did not account for tumour heterogeneity, and pathway inhibition was limited to pharmacologic approaches. RNA-seq of paired PCa samples revealed ADT-regulated signalling pathways. Proof-of-principle inhibition of the Wnt/β-catenin signalling pathway specifically delays androgen-independent PCa cell cycle progression and proliferation and warrants further investigation as a potential target for therapy for CRPC.

Rajan P ，Sudbery IM ，Villasevil ME ，Mui E ，Fleming J ，Davis M ，Ahmad I ，Edwards J ，Sansom OJ ，Sims D ，Ponting CP ，Heger A ，McMenemin RM ，Pedley ID ，Leung HY ... -  《-》

Patient-derived Hormone-naive Prostate Cancer Xenograft Models Reveal Growth Factor Receptor Bound Protein 10 as an Androgen Receptor-repressed Gene Driving the Development of Castration-resistant Prostate Cancer.

Although androgen deprivation therapy is initially effective in controlling growth of hormone-naive prostate cancers (HNPCs) in patients, currently incurable castration-resistant prostate cancer (CRPC) inevitably develops. To identify CRPC driver genes that may provide new targets to enhance CRPC therapy. Patient-derived xenografts (PDXs) of HNPCs that develop CRPC following host castration were examined for changes in expression of genes at various time points after castration using transcriptome profiling analysis; particular attention was given to pre-CRPC changes in expression indicative of genes acting as potential CRPC drivers. The functionality of a potential CRPC driver was validated via its knockdown in cultured prostate cancer cells; its clinical relevance was established using data from prostate cancer patient databases. Eighty genes were found to be significantly upregulated at the CRPC stage, while seven of them also showed elevated expression prior to CRPC development. Among the latter, growth factor receptor bound protein 10 (GRB10) was the most significantly and consistently upregulated gene. Moreover, elevated GRB10 expression in clinical prostate cancer samples correlated with more aggressive tumor types and poorer patient treatment outcome. GRB10 knockdown markedly reduced prostate cancer cell proliferation and activity of AKT, a well-established CRPC mediator. A positive correlation between AKT activity and GRB10 expression was also found in clinical cohorts. GRB10 acts as a driver of CRPC and sensitizes androgen receptor pathway inhibitors, and hence GRB10 targeting provides a novel therapeutic strategy for the disease. Development of castration-resistant prostate cancer (CRPC) is a major problem in the management of the disease. Using state-of-the-art patient-derived hormone-naive prostate cancer xenograft models, we found and validated the growth factor receptor bound protein 10 gene as a driver of CRPC, indicating that it may be used as a new molecular target to enhance current CRPC therapy.

Hao J ，Ci X ，Xue H ，Wu R ，Dong X ，Choi SYC ，He H ，Wang Y ，Zhang F ，Qu S ，Zhang F ，Haegert AM ，Gout PW ，Zoubeidi A ，Collins C ，Gleave ME ，Lin D ，Wang Y ... -  《-》

Leukemia Inhibitory Factor Promotes Castration-resistant Prostate Cancer and Neuroendocrine Differentiation by Activated ZBTB46.

The molecular targets for castration-resistant prostate cancer (CRPC) are unknown because the disease inevitably recurs, and therapeutic approaches for patients with CRPC remain less well understood. We sought to investigate regulatory mechanisms that result in increased therapeutic resistance, which is associated with neuroendocrine differentiation of prostate cancer and linked to dysregulation of the androgen-responsive pathway. The underlying intracellular mechanism that sustains the oncogenic network involved in neuroendocrine differentiation and therapeutic resistance of prostate cancer was evaluated to investigate and identify effectors. Multiple sets of samples with prostate adenocarcinomas and CRPC were assessed via IHC and other assays. We demonstrated that leukemia inhibitory factor (LIF) was induced by androgen deprivation therapy (ADT) and was upregulated by ZBTB46 in prostate cancer to promote CRPC and neuroendocrine differentiation. LIF was found to be induced in patients with prostate cancer after ADT and was associated with enriched nuclear ZBTB46 staining in high-grade prostate tumors. In prostate cancer cells, high ZBTB46 output was responsible for the activation of LIF-STAT3 signaling and neuroendocrine-like features. The abundance of LIF was mediated by ADT-induced ZBTB46 through a physical interaction with the regulatory sequence of LIF. Analysis of serum from patients showed that cases of higher tumor grade and metastatic prostate cancer exhibited higher LIF titers. Our findings suggest that LIF is a potent serum biomarker for diagnosing advanced prostate cancer and that targeting the ZBTB46-LIF axis may therefore inhibit CRPC development and neuroendocrine differentiation after ADT.

Liu YN ，Niu S ，Chen WY ，Zhang Q ，Tao Y ，Chen WH ，Jiang KC ，Chen X ，Shi H ，Liu A ，Li J ，Li Y ，Lee YC ，Zhang X ，Huang J ... -  《-》