Efficacy and Safety of Combined Androgen Deprivation Therapy (ADT) and Docetaxel Compared with ADT Alone for Metastatic Hormone-Naive Prostate Cancer: A Systematic Review and Meta-Analysis

The efficacy and safety of PARP inhibitors in mCRPC with HRR mutation in second-line treatment: a systematic review and bayesian network meta-analysis

BACKGROUND

Poly (ADP- ribose) polymerase inhibitors (PARPi) has been increasingly adopted for metastatic castration-resistance prostate cancer (mCRPC) patients with homologous recombination repair deficiency (HRD). However, it is unclear which PARPi is optimal in mCRPC patients with HRD in 2nd -line setting.

METHOD

We conducted a systematic review of trials regarding PARPi- based therapies on mCRPC in 2nd -line setting and performed a Bayesian network meta-analysis (NMA). Radiographic progression-free survival (rPFS) was assessed as primary outcome. PSA response and adverse events (AEs) were evaluated as secondary outcomes. Subgroup analyses were performed according to specific genetic mutation.

RESULTS

Four RCTs comprised of 1024 patients (763 harbored homologous recombination repair (HRR) mutations) were identified for quantitative analysis. Regarding rPFS, olaparib monotherapy, rucaparib and cediranib plus olaparib showed significant improvement compared with ARAT. Olaparib plus cediranib had the highest surface under cumulative ranking curve (SUCRA) scores (87.5%) for rPFS, followed by rucaparib, olaparib and olaparib plus abiraterone acetate prednisone. For patients with BRCA 1/2 mutations, olaparib associated with the highest probability (98.1%) of improved rPFS. For patients with BRCA-2 mutations, olaparib and olaparib plus cediranib had similar efficacy. However, neither olaparib nor rucaparib showed significant superior effectiveness to androgen receptor-axis-targeted therapy (ARAT) in patients with ATM mutations. For safety, olaparib showed significantly lower ≥ 3 AE rate compared with cediranib plus olaparib (RR: 0.72, 95% CI: 0.51, 0.97), while olaparib plus cediranib was associated with the highest risk of all-grade AE.

CONCLUSION

PARPi-based therapy showed considerable efficacy for mCRPC patients with HRD in 2nd -line setting. However, patients should be treated accordingly based on their genetic background as well as the efficacy and safety of the selected regimen.

TRIAL REGISTRATION

CRD42023454079.

Efficacy of Treatment for Metastatic Hormone-Sensitive Prostate Cancer: An Umbrella Review of Systematic Reviews and Meta-Analyses

PURPOSE

This umbrella review focused on evaluating the efficacy and adverse events of the metastatic hormone-sensitive prostate cancer patients receiving any treatment regimens, including ADT alone or combination treatments.

METHODS

This study conducted an umbrella review following the PRISMA 2020 checklist, aiming to summarize the available studies to evaluate the efficacy of medical treatments for metastatic hormone-sensitive prostate cancer. A literature search was performed to identify systematic reviews and meta-analyses (SRMAs) that included only randomized controlled trials (RCTs) up to September 2023. This study summarized their findings, evaluated overlapping data (i.e., the same RCTs were included in >one SRMA), tested for excessive significance (i.e., observed number of statistically significant studies > expected number by chance) and assessed the quality of the studies.

RESULTS

A total of 4191 studies were identified, but only 27 were included. Among those 27 studies, 12 were network meta-analyses and 15 were direct meta-analyses. Most studies showed no statistically significant difference in overall mortality among GnRH agonists, antagonists and bilateral orchiectomy. Combination treatment is more beneficial than ADT alone in both OS and PFS outcomes with more adverse events. Nevertheless, there is no OS advantage of any combination regimen over the others.

CONCLUSION

Combination treatments demonstrated clear benefits in OS and PFS over ADT alone with more AEs. Further studies are needed to compare among combination treatments.

Current Trends in Chemotherapy in the Treatment of Metastatic Prostate Cancer

Prostate cancer is the second most common cancer among men. Despite advances in diagnosis and management, prostate cancer led to more than 300,000 deaths globally in 2020. Chemotherapy is a cornerstone of therapy for advanced prostate cancer and can prolong survival of patients with both castration-sensitive and castration-resistant disease. Herein, we present a comprehensive review of the data supporting implementation of chemotherapy in the modern treatment of advanced prostate cancer, with special attention to the use of chemotherapy for aggressive variant prostate cancer (e.g., neuroendocrine prostate cancer) and the combination of chemotherapy with androgen signaling inhibitors. As the field of prostate cancer research continues to rapidly evolve yielding novel agents and treatment modalities, chemotherapy continues to play an essential role in prolonging the survival of patients with advanced and metastatic prostate cancer.

Stereotactic radiotherapy of nodal oligometastases from prostate cancer: a prisma-compliant systematic review

Androgen deprivation therapy (ADT) is the standard treatment of metastatic prostate cancer (PCa). However, metastases-directed therapies can delay the initiation or switch of systemic treatments and allow local control (LC) and prolonged progression-free survival (PFS), particularly in patients with lymph nodes (LN) oligometastases. We performed a systematic review on stereotactic body radiotherapy (SBRT) in this setting. Papers reporting LC and/or PFS were selected. Data on ADT-free survival, overall survival, and toxicity were also collected from the selected studies. Fifteen studies were eligible (414 patients), 14 of them were retrospective analyses. A high heterogeneity was observed in terms of patient selection and treatment. In one study SBRT was delivered as a single 20 Gy fraction, while in the others the median total dose ranged between 24 and 40 Gy delivered in 3-6 fractions. LC and PFS were reported in 15 and 12 papers, respectively. LC was reported as a crude percentage in 13 studies, with 100% rate in seven and 63.2-98.0% in six reports. Five studies reported actuarial LC (2-year LC: 70.0-100%). PFS was reported as a crude rate in 11 studies (range 27.3-68.8%). Actuarial 2-year PFS was reported in four studies (range 30.0-50.0%). SBRT tolerability was excellent, with only two patients with grade 3 acute toxicity and two patients with grade 3 late toxicity. SBRT for LN oligorecurrences from PCa in safe and provides optimal LC. However, the long-term effect on PFS and OS is still unclear as well as which patients are the best candidate for this approach.

1.5 T MR-Guided Daily Adapted SBRT on Lymph Node Oligometastases from Prostate Cancer

Introduction: The aim of our study was to evaluate the efficacy and toxicity of a daily adaptive MR-guided SBRT on 1.5 T MR-linac in patients affected by lymph node oligometastases from PCa. Materials and Methods: The present study is a prospective observational study conducted in a single institution (protocol n°: MRI/LINAC n. 23748). Patients with oligometastatic lymph nodes from PCa treated with daily adaptive MR-guided SBRT on 1.5 T MR-linac were included in the study. There was a minimum required follow-up of 3 months after SBRT. The primary end-point was local progression-free survival (LPFS). The secondary end-points were: nodal progression-free survival (NPFS), progression-free survival (PFS), and toxicity. Results: A total of 118 lymph node oligometastases from PCa were treated with daily adaptive 1.5 T MR-guided SBRT in 63 oligometastatic patients. Of the patients, 63.5% were oligorecurrent and 36.5% were oligoprogressive. The two-year LPFS was 90.7%. The median NPFS was 22.3 months and the 2-year NPFS was 46.5%. Receiving hormone therapy before SBRT was correlated with a lower NPFS at the multivariate analysis (1 y NPFS 87.1% versus 42.8%; p = 0.002-HR 0.199, 95% CI 0.073-0.549). Furthermore, the oligorecurrent state during ADT was correlated with a lower NPFS than was the oligoprogressive state. The median PFS was 10.3 months and the 2-year PFS was 32.4%. Patients treated with hormone therapy before SBRT had a significantly lower 1-year PFS the others (28% versus 70.4%; p = 0.01-HR 0.259, 95% CI 0.117-0.574). No acute and late toxicities occurred during treatment. Conclusions: The present study is the largest prospective study of 1.5 T lymph node SBRT on MR-linac in patients with PCa. Lymph node SBRT by 1.5 T MR-linac provides high local control rates with an excellent toxicity profile.

Addition of androgen receptor targeted agents to androgen deprivation therapy and docetaxel in metastatic hormone-sensitive prostate cancer: a systematic review and meta-analysis

Background

Androgen-deprivation therapy (ADT) historically represented the milestone for the treatment of metastatic hormone-sensitive prostate cancer (mHSPC). Recently, combining androgen receptor-targeted agents (ARTA) or docetaxel with ADT significantly improved clinical outcomes in this setting. The efficacy of the combined use of an ARTA with docetaxel and ADT (triplet), however, was unknown, and often conflicting data derived from subgroup analysis of randomized phase III trials. In order to better define the benefits and risks of the triplet in mHSPC, we carried out a systematic review and meta-analysis of available clinical trials.

Methods

A literature search with no data restriction using Medline/PubMed, the Cochrane Library, and American Society of Clinical Oncology/European Society for Medical Oncology (ASCO/ESMO) Meeting abstracts was carried out up to April 2022. The meta-analysis was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statements. Overall survival (OS) was the primary endpoint; progression-free survival (PFS) and safety were secondary endpoints. For OS and PFS, summary hazard ratios (HRs) were calculated; for safety, risk ratio (RR) was assessed. Random- or fixed-effects models were used, depending on studies heterogeneity.

Results

Five randomized clinical trials fulfilled the prespecified inclusion criteria. The triplet significantly improved OS (fixed-effect, HR = 0.74; P < 0.00001) and PFS (fixed-effect; HR = 0.50 for clinical PFS, HR = 0.49 for radiological PFS; P < 0.0001) compared with docetaxel plus ADT. We did not show heterogeneity between treatment efficacy and the disease burden, metachronous versus synchronous presentation, concomitant versus sequential strategy. Compared with docetaxel + ADT, the triplet did not increase the risk of adverse events (AEs) (RR = 1.00, P = 0.27 for any-grade AEs; RR = 1.13, P = 0.14 for severe AEs), except for severe hypertension (RR = 1.73, P = 0.001).

Conclusions

Emerging evidence supports the combination of an ARTA plus docetaxel and ADT in mHSPC patients. Given the availability of several strategies in this setting, clinical characteristics and drug safety profile may help clinicians select the appropriate treatment for mHSPC patients who are more likely to benefit from treatment intensification.

•

The addition of ARTA or docetaxel to ADT improved survival in mHSPC.

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Recently, the combination of ARTA plus docetaxel and ADT (triplet) versus docetaxel plus ADT has been investigated.

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The triplet prolonged OS and PFS compared with docetaxel plus ADT and represents a potential practice-changing treatment.

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Clinical characteristics and drug safety profile may help clinicians to select the appropriate treatment for mHSPC.

Randomised double-blind phase 3 clinical study testing impact of atorvastatin on prostate cancer progression after initiation of androgen deprivation therapy: study protocol

INTRODUCTION

Blood cholesterol is likely a risk factor for prostate cancer prognosis and use of statins is associated with lowered risk of prostate cancer recurrence and progression. Furthermore, use of statins has been associated with prolonged time before development of castration resistance (CR) during androgen deprivation therapy (ADT) for prostate cancer. However, the efficacy of statins on delaying castration-resistance has not been tested in a randomised placebo-controlled setting.This study aims to test statins' efficacy compared to placebo in delaying development of CR during ADT treatment for primary metastatic or recurrent prostate cancer. Secondary aim is to explore effect of statin intervention on prostate cancer mortality and lipid metabolism during ADT.

METHODS AND ANALYSIS

In this randomised placebo-controlled trial, a total of 400 men with de novo metastatic prostate cancer or recurrent disease after primary treatment and starting ADT will be recruited and randomised 1:1 to use daily 80 mg of atorvastatin or placebo. All researchers, study nurses and patients will be blinded throughout the trial. Patients are followed until disease recurrence or death. Primary outcome is time to formation of CR after initiation of ADT. Serum lipid levels (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and trigyserides) are analysed to test whether changes in serum cholesterol parameters during ADT predict length of treatment response. Furthermore, the trial will compare quality of life, cardiovascular morbidity, changes in blood glucose and circulating cell-free DNA, and urine lipidome during trial.

ETHICS AND DISSEMINATION

This study is approved by the Regional ethics committees of the Pirkanmaa Hospital District, Science centre, Tampere, Finland (R18065M) and Tarto University Hospital, Tarto, Estonia (319/T-6). All participants read and sign informed consent form before study entry. After publication of results for the primary endpoints, anonymised summary metadata and statistical code will be made openly available. The data will not include any information that could make it possible to identify a given participant.

TRIAL REGISTRATION NUMBER

Clinicaltrial.gov: NCT04026230, Eudra-CT: 2016-004774-17, protocol code: ESTO2, protocol date 10 September 2020 and version 6.

Management of Advanced Prostate Cancer in Clinical Practice: Real-World Answers to Challenging Dilemmas

Advanced prostate cancer is a continuum of states distinguished by the presence or absence of metastasis and sensitivity or resistance to androgen deprivation therapy (ADT). Therapeutic options for this disease continue to rapidly evolve, making it a challenge to apply results of clinical trial data to daily patient management. One question relevant to providers is whether molecular biomarkers predictive of response or resistance to therapies are available to guide clinical treatment decisions. Other salient topics include the timing of therapy initiation in patients with biochemical recurrence, treatment approach in low-volume versus high-volume metastatic castrate-sensitive prostate cancer, types of agents available beyond ADT, and timing of their use in men with nonmetastatic castrate-resistant prostate cancer as well as whether sequencing of therapies in metastatic castrate-resistant prostate cancer matters. Additionally, familiarity with emerging treatment strategies is important. This review addresses the gray areas and challenging questions in advanced prostate cancer management that frequently arise in clinical practice.

Effect of Adding Docetaxel to Androgen-Deprivation Therapy in Patients With High-Risk Prostate Cancer With Rising Prostate-Specific Antigen Levels After Primary Local Therapy: A Randomized Clinical Trial

Importance

Androgen-deprivation therapy (ADT) plus docetaxel is the standard of care in hormone-naive metastatic prostate cancer but is of uncertain benefit in a nonmetastatic, high-risk prostate cancer setting.

Objective

To assess the benefit of ADT plus docetaxel in patients presenting with rising prostate-specific antigen (PSA) levels after primary local therapy and high-risk factors but no evidence of metastatic disease.

Design, Setting, and Participants

This open-label, phase 3, randomized superiority trial comparing ADT plus docetaxel vs ADT alone enrolled patients from 28 centers in France between June 4, 2003, and September 25, 2007; final follow-up was conducted April 12, 2017, and analysis was performed May 2 to July 31, 2017. Patients had undergone primary local therapy for prostate cancer, were experiencing rising PSA levels, and were considered to be at high risk of metastatic disease. Stratification was by prior local therapy and PSA-level doubling time (≤6 vs >6 months), and intention-to-treat analysis was used.

Interventions

Patients were randomly assigned to receive ADT (1 year) plus docetaxel, 70 mg/m2 (every 3 weeks [6 cycles]), or ADT alone (1 year).

Main Outcomes and Measures

The primary outcome was PSA progression-free survival (PSA-PFS). Secondary end points were PSA response, radiologic PFS, overall survival, safety, and quality of life.

Results

Overall, 254 patients were randomized (1:1) to the trial; median age, 64 years in the ADT plus docetaxel arm, 66 years in the ADT alone arm. At a median follow-up of 30.0 months, the median PSA-PFS was 20.3 (95% CI, 19.0-21.6) months in the ADT plus docetaxel arm vs 19.3 (95% CI, 18.2-20.8) months in the ADT alone arm (hazard ratio [HR], 0.85; 95% CI, 0.62-1.16; P = .31). At a median follow-up of 10.5 years, there was no significant between-arm difference in radiologic PFS (HR, 1.03; 95% CI, 0.74-1.43; P = .88). Overall survival data were not mature. The most common grade 3 or 4 hematologic toxic effects in the ADT plus docetaxel arm were neutropenia (60 of 125 patients [48.0%]), febrile neutropenia (10 [8.0%]), and thrombocytopenia (4 [3.0%]). There was no significant between-arm difference in overall quality of life.

Conclusions and Relevance

Compared with ADT alone, combined ADT plus docetaxel therapy with curative intent did not significantly improve PSA-PFS in patients with high-risk prostate cancer and rising PSA levels and no evidence of metastatic disease.

Trial Registration

French Health Products Safety Agency identifier: 030591; ClinicalTrials.gov identifier: NCT00764166.

Cost-effectiveness of docetaxel in high-volume hormone-sensitive metastatic prostate cancer

INTRODUCTION

Three pivotal trials have considered the addition of docetaxel (D) chemotherapy to conventional androgen-deprivation therapy (ADT) for the treatment of metastatic hormone- sensitive prostate cancer (HSPC). While an initial small trial was inconclusive, two larger trials demonstrated significant clinical benefit, including pronounced survival benefits (added 17 months) among patients with high-volume metastatic disease. Given the evolving clinical evidence, the cost-effectiveness of this approach warrants exploration.

METHODS

The cost-effectiveness of six cycles of ADT+D compared to ADT alone to treat patients with high-volume metastatic HSPC was assessed from a Canadian public payer perspective. We included three health states: HSPC, metastatic castration-resistant prostate cancer (CRPC), and death. Survival data were obtained from the CHAARTED trial, which reported outcomes specifically for high-volume disease. We used Ontario costs data and utilities from the literature.

RESULTS

In the base case analysis, ADT+D cost an additional $25 757 and produced an extra 1.06 quality-adjusted life years (QALYs), resulting in an incremental cost-effectiveness ratio (ICER) of $24 226/QALY gained. Results from one-way sensitivity analysis across wide ranges of estimates and a range of scenarios, including an alternate model structure, produced ICERs below $35 000/QALY gained in all cases.

CONCLUSIONS

The use of D with ADT in high-volume metastatic HSPC appears to be an economically attractive treatment approach. The findings were consistent with other studies and robust in sensitivity analysis across a variety of scenarios.

Different therapeutic regimens in the treatment of metastatic prostate cancer by performing a Bayesian network meta-analysis

BACKGROUND

Although androgen deprivation therapy with or without chemotherapy are currently the mainstay of therapy for metastatic prostate cancer, accumulating data suggested the survival benefits from definitive local therapy such as radical prostatectomy or radiation therapy. Hence, this network meta-analysis was aimed to provide a hierarchy of different therapeutic regimens for mPCa.

METHODS

Relevant studies were retrieved comprehensively by searching the online databases of PubMed, EMBASE and Web of Science, published before July 1st, 2018. With the help of R-3.4.0 software and "gemtc-0.8.2" package, network meta-analysis was performed by random-effect model within a Bayesian framework. Hazard ratios and corresponding 95% credible intervals were calculated by Markov chain Monte Carlo methods. The surface under the cumulative ranking curve was also incorporated to rank the corresponding therapeutic regimens.

RESULTS

A total of 55,363 cases from 17 studies were ultimately involved in this study. Ten different therapeutic regimens and three clinical endpoints were finally assessed. As illustrated by our results, local therapy (such as radical prostatectomy or radiation therapy) could provide a relatively more favorable survival rate than systematic therapies (no local therapy, androgen deprivation therapy or androgen deprivation therapy + chemotherapy). Meanwhile, in the comparison of radiation therapy, brachytherapy and intensity modulated radiation therapy were among the best two therapies. Furthermore, radical prostatectomy had a relatively lower cancer specific mortality or all-cause mortality than brachytherapy or intensity modulated radiation therapy, in the comparison of local therapy, whereas brachytherapy showed a relatively longer overall survival than radical prostatectomy.

CONCLUSIONS

Our results indicated that local therapy was better than no local therapy. In a comprehensive comparison of three clinical endpoints (overall survival, cancer specific mortality or all-cause mortality), radical prostatectomy had a relatively lower cancer specific mortality or all-cause mortality than radiation therapy, whereas brachytherapy was superior to radical prostatectomy for overall survival.

Efficacy and safety of combined androgen blockade with antiandrogen for advanced prostate cancer

Background

Combined androgen blockade (cab) is a promising treatment modality for prostate cancer (pca). In the present meta-analysis, we compared the efficacy and safety of first-line cab using an antiandrogen (aa) with castration monotherapy in patients with advanced pca.

Methods

PubMed, embase, Cochrane, and Google Scholar were searched for randomized controlled trials (rcts) published through 12 December 2016. Hazard ratios (hrs) with 95% confidence intervals (cis) were determined for primary outcomes: overall survival (os) and progression-free survival (pfs). Subgroup analyses were performed for Western compared with Eastern patients and use of a nonsteroidal aa (nsaa) compared with a steroidal aa (saa).

Results

Compared with castration monotherapy, cab using an aa was associated with significantly improved os (n = 14; hr: 0.90; 95% ci: 0.84 to 0.97; p = 0.003) and pfs (n = 13; hr: 0.89; 95% ci: 0.80 to 1.00; p = 0.04). No significant difference in os (p = 0.71) and pfs (p = 0.49) was observed between the Western and Eastern patients. Compared with castration monotherapy, cab using a nsaa was associated with significantly improved os (hr: 0.88; 95% ci: 0.82 to 0.95; p = 0.0009) and pfs (hr: 0.85; 95% ci: 0.73 to 0.98; p = 0.007)-a result that was not achieved with cab using a saa. The safety profiles of cab and monotherapy were similar in terms of adverse events, including hot flushes, impotence, and grade 3 or 4 events, with the exception of risk of diarrhea and liver dysfunction or elevation in liver enzymes, which were statistically greater with cab using an aa.

Conclusions

Compared with castration monotherapy, first-line cab therapy with an aa, especially a nsaa, resulted in significantly improved os and pfs, and had an acceptable safety profile in patients with advanced pca.

Taxane-based chemohormonal therapy for metastatic hormone-sensitive prostate cancer

BACKGROUND

There has been considerable development in the treatment of advanced prostate cancer over the last decade. A number of agents, including docetaxel, cabazitaxel, abiraterone acetate, enzalutamide and sipuleucel-T, have been reported to improve outcomes in men with castration-resistant disease and their use is being explored in hormone-sensitive prostate cancer.

OBJECTIVES

To assess the effects of early taxane-based chemohormonal therapy for newly diagnosed, metastatic, hormone-sensitive prostate cancer.

SEARCH METHODS

We performed a comprehensive search using multiple databases (the Cochrane Library, MEDLINE, Embase, Scopus, Google Scholar, and Web of Science), trials registries, other sources of grey literature, and conference proceedings, up to 10 August 2018. We applied no restrictions on publication language or status.

SELECTION CRITERIA

We included randomized or quasi-randomized controlled trials in which participants were administered taxane-based chemotherapy with systemic androgen deprivation therapy (ADT) within 120 days of beginning ADT versus ADT alone at the time of diagnosis of metastatic disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies and abstracted data from the included studies. We performed statistical analyses using a random-effects model. We rated the quality of evidence according to the GRADE approach.

MAIN RESULTS

The search identified three studies in which 2,261 participants were randomized to receive either ADT alone, or taxane-based chemotherapy at a dose of 75mg per square meter of body surface area at three-weekly intervals for six or nine cycles in addition to ADT.Primary outcomesEarly treatment with taxane-based chemotherapy in addition to ADT probably reduces death from any cause compared to ADT alone (hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.68 to 0.87; moderate-certainty evidence); this would result in 94 fewer deaths per 1,000 men (95% CI 51 to 137 fewer deaths). We downgraded the certainty of evidence due to study limitations related to potential performance bias. Based on the results of one study with 375 participants, the addition of taxane-based chemotherapy to ADT may increase the incidence of Grade III to V adverse events compared to ADT alone (risk ratio (RR) 2.98, 95% CI 2.19 to 4.04; low-certainty evidence); this would result in 405 more Grade III to V adverse events per 1,000 men (95% CI 243 to 621 more events). We downgraded the certainty of evidence due to study limitations and imprecision.Secondary outcomesEarly taxane-based chemotherapy in addition to ADT probably reduces the risk of prostate cancer-specific death (RR 0.79, 95% CI 0.70 to 0.89; moderate-certainty evidence). We downgraded the certainty of evidence due to study limitations related to potential performance and detection bias. The addition of taxane-based chemotherapy also probably reduces disease progression compared to ADT alone (HR 0.63, 95% CI 0.56 to 0.71; moderate-certainty evidence). We downgraded the certainty of evidence because of study limitations related to potential performance bias. The addition of taxane-based chemotherapy to ADT may result in a large increase in the risk of treatment discontinuation due to adverse events (RR 79.41, 95% CI 4.92 to 1282.78; low-certainty evidence). We downgraded the certainty of evidence due to study limitations and imprecision. This estimate is derived from a single study with no events in the control arm but a discontinuation rate of 20% in the intervention arm. Taxane-based chemotherapy may increase the incidence of adverse events of any grade (RR 1.11, 95% CI 1.06 to 1.17; low-certainty evidence). We downgraded our assessment of the certainty of evidence due to very serious study limitations. There may be a small improvement, which may not be clinically important, in quality of life at 12 months with combination treatment (mean difference (MD) 2.85 on the Functional Assessment of Cancer Therapy-Prostate scale, 95% CI 0.13 higher to 5.57 higher; low-certainty evidence). We downgraded the certainty of evidence for study limitations related to potential performance, detection and attrition bias.

AUTHORS' CONCLUSIONS

Compared to ADT alone, the early (within 120 days of beginning ADT) addition of taxane-based chemotherapy to ADT for hormone-sensitive prostate cancer probably prolongs both overall and disease-specific survival and delays disease progression. There may be an increase in toxicity with taxane-based chemotherapy in combination with ADT. There may also be a small, clinically unimportant improvement in quality of life at 12 months with taxane-based chemotherapy and ADT treatment.

Recent advances on the progressive mechanism and therapy in castration-resistant prostate cancer

Background

Although there have been great advances in mechanisms and therapeutic methods of prostate cancer, the mortality rate of prostate cancer remains high. The castration-resistant prostate cancer (CRPC), which develops from hormone-sensitive prostate cancer, foreshadows a more dismal outcome. Concomitant with the researches in the mechanism of CRPC and therapy for CRPC, more and more landmark progress has been made in recent years.

Methods

A number of clinical and experimental studies were reviewed to indicate the novel advancement in the progressive mechanism and therapy of CRPC.

Results

The androgen receptor (AR) is still a vital driver in the progression of CRPC, while other multiple mechanisms also contribute to this progression, such as tumor immunity, cancer stem cells, epithelial–mesenchymal transition and DNA repair disorder. In terms of the therapeutic methods of CRPC, chemotherapy with drugs, such as docetaxel, has been the first-line therapy for CRPC for many years. Besides, newer agents, which target some of the above mechanisms, show additional overall survival benefits for CRPC patients. These therapies include drugs targeting the androgen axis pathway (androgen synthesis, androgen receptor splice variants, coactivators of AR and so on), PI3K-AKT pathway, WNT pathway, DNA repair, rearrangement of ETS gene, novel chemotherapy and immunotherapy, bone metastasis therapy and so on. Understanding these novel findings on the mechanisms of CRPC and the latest potential CRPC therapies will direct us for further exploration of CRPC.

Conclusion

Through comprehensive consideration, the predominant mechanism of CRPC might be the AR signal axis concomitant with tumor microenvironment, stress, immunity, tumor microenvironment and so on. For CRPC therapy, targeting the AR axis pathway and chemotherapy are the first-line treatments at present. However, with the advancements in CRPC therapy made by the researchers, other novel potential methods will occupy more and more important position in the treatment of CRPC, especially the therapies targeting the tumor microenviroment, tumor immunity and DNA repair and so on.

Polymer micro/nanocarrier-assisted synergistic chemohormonal therapy for prostate cancer

Polymer micro/nanocarrier-assisted chemohormonal therapy upregulates chemotherapy efficacy and down-regulates hormone level, effectively inhibiting the progression of prostate cancer.

STAMPEDEing metastatic prostate cancer: CHAARTing the LATITUDEs

With the emergence of recent landmark trials, the treatment for hormone-sensitive metastatic prostate cancer (hsMPC) is changing from androgen deprivation therapy (ADT) alone to combination therapy. Both, docetaxel chemotherapy and abiraterone in addition to ADT have been extensively studied in well-conducted randomized controlled trials and were shown to improve outcomes. However, this paradigm shift in the treatment has also raised some queries. This mini review reflects upon the four landmark trials and tries to provide some perspective about the decision-making process for the patients with hsMPC.

The evolution of chemotherapy for the treatment of prostate cancer

Chemotherapy has been explored as a treatment option for metastatic prostate cancer since the early 1980s. Docetaxel, a taxane chemotherapeutic, was approved for the treatment of men with metastatic castration-resistant prostate cancer in 2004, and is now standard of care for late stage disease. Recent clinical studies demonstrated that patients with metastatic castration-sensitive disease, and possibly those with high-risk localized prostate cancer also benefit from docetaxel administration, expanding the role of chemotherapy in the prostate cancer treatment landscape. Another taxane, cabazitaxel, is approved for post-docetaxel metastatic castration-resistant prostate cancer. Taxanes and other chemotherapeutics, such as carboplatin, are now being tested in combination regimens. This review presents an outline of recent and ongoing clinical studies assessing docetaxel and its derivative cabazitaxel at different stages of the disease, and in various combinations with other agents. We summarize current knowledge on biomarkers predictive of response to chemotherapy, which may in future be used to guide individualized treatment decisions.

Knockdown of Mediator Complex Subunit 19 Suppresses the Growth and Invasion of Prostate Cancer Cells

Prostate cancer (PCa) is one of the most common cancers in elderly men. Mediator Complex Subunit 19 (Med19) is overexpressed and plays promotional roles in many cancers. However, the roles of Med19 in PCa are still obscure. In this study, by using immunohistochemical staining, we found higher expression level of Med19 in PCa tissues than in adjacent benign prostate tissues. We then knocked down the Med19 expression in PCa cell lines LNCaP and PC3 by using lentivirus siRNA. Cell proliferation, anchor-independent growth, migration, and invasion were suppressed in Med19 knockdown PCa cells. In nude mice xenograft model, we found that Med19 knockdown PCa cells formed smaller tumors with lower proliferation index than did control cells. In the mechanism study, we found that Med19 could regulate genes involved in cell proliferation, cell cycle, and epithelial-mesenchymal transition, including P27, pAKT, pPI3K, IGF1R, E-Cadherin, N-Cadherin, Vimentin, ZEB2, Snail-1 and Snail-2. Targeting Med19 in PCa cells could inhibit the PCa growth and metastasis, and might be a therapeutic option for PCa in the future.

The Effects and Mechanism of YK-4-279 in Combination with Docetaxel on Prostate Cancer

Background: Docetaxel is the first-line treatment for castration-resistant prostate cancer (CRPC). The limited survival benefit associated with the quick emergence of resistance and systemic toxicity diminishes its efficacy in high-dose monotherapy. YK-4-279 is a small molecule inhibitor of ETV1 that plays an important role in the progression of prostate cancer. The aim of this study was to evaluate the hypothesis that the combination of docetaxel and YK-4-279 will have a synergistic effect on inhibiting growth and accelerating apoptosis in human prostate cancer cells. Methods: Cell growth assessed using CCK-8 and trypan blue exclusion assays. Cell apoptosis was determined by morphological assessment in cells stained with propidium iodide. Standard scratch migration and Matrigel-coated transwell invasion assays were used to assess cell migration and invasion, respectively. Western blotting was used to investigate the levels of ETV1, AR, PSA, p-STAT3, survivin, Bcl-2, and p-Akt in prostate cancer cells. Results: The combination of low-dose docetaxel and YK-4-279 synergistically inhibited growth and induced apoptosis in human prostate cancer cells. The combination also more efficiently suppressed the migration and invasion of LNCaP and PC-3 cells. The combination of low-dose docetaxel and YK-4-279 caused a stronger decrease in the levels of ETV1, AR, PSA, p-STAT3, survivin, Bcl-2, and p-Akt in LNCaP cells and of p-Akt, Bcl-2, and p-STAT3 in PC-3 cells compared with either drug alone. Conclusions: These data suggest that the combination of docetaxel and YK-4-279 may be an effective approach for inhibiting the growth and metastasis of prostate cancer. This could permit a decrease in the docetaxel dose necessary for patients with CRPC and thereby lower its systemic toxicity.