Cytoreductive treatment strategies for de novo metastatic prostate cancer

Association between Statin Use and Clinical Outcomes in Patients with De Novo Metastatic Prostate Cancer: A Propensity Score-weighted Analysis

PURPOSE

Numerous studies have produced conflicting findings regarding the efficacy of statins in prostate cancer treatment. Our objective was to examine the correlation between statin usage and clinical outcomes in Taiwanese men with de novo metastatic prostate cancer.

MATERIALS AND METHODS

We identified patients diagnosed with de novo metastatic prostate cancer from the Chang Gung Research Database spanning the years 2007 to 2020. To minimize confounding bias, we employed the inverse probability of treatment weighting (IPTW) method. Clinical outcomes were assessed using IPTW-adjusted Kaplan-Meier curves. Multivariate Cox proportional hazard regression analysis was utilized to evaluate the association between mortality and clinical factors.

RESULTS

The study cohort comprised 1,716 statin users and 276 non-users. Patients who used statins exhibited a longer median overall survival (85.4 months compared to 58.2 months; p=0.001) and cancer-specific survival (112.6 months compared to 75.7 months; p<0.001) compared to non-users. The median time to the development of castration-resistant status was similar between statin users and non-users (p=0.069). Multivariable Cox proportional hazards regression analysis, after IPTW adjustment, demonstrated that statin use was associated with improved overall survival.

CONCLUSIONS

Our study indicates that the use of statins following a de novo metastatic prostate cancer diagnosis enhances survival outcomes. However, statins did not appear to delay the onset of castration-resistant status. Further large-scale and long-term studies are warranted to investigate the biological effects of statins in men with prostate cancer.

Role of cytoreductive radical prostatectomy in men with oligometastatic prostate cancer on molecular imaging

PURPOSE OF REVIEW

The implementation of PET with prostate-specific membrane antigen (PSMA) tracer as primary staging tool occurred recently. Since its introduction, a novel category of patients emerged, with negative staging at conventional imaging, and positive molecular imaging. Local treatment in these patients might be associated with improved oncological outcomes when combined with systemic therapy. However, its impact on oligometastatic prostate cancer (omPCa) remains unknown. In this review, we aimed at investigating the role of cytoreductive radical prostatectomy (cRP) in oligometastatic disease at molecular imaging.

RECENT FINDINGS

After comprehensive review of literature, two retrospective studies highlighted the feasibility, safety, and potential benefits of surgery in omPCA patients at molecular imaging. They showed that 72% of patients achieved PSA less than 0.01 ng/ml following cRP as part of a multimodal approach, 17% experienced radiographic progression, and 7% died at 27-month median follow-up. Moreover, complications postcRP after PSMA PET were modest, with a 40% rate of any adverse event, and 5% of grade more than 3. The 1-year urinary continence after cRP rate was 82%. The oncological, functional outcomes and the complication rate aligned with those observed in series of cRP after conventional imaging.

SUMMARY

cRP is feasible, well tolerated, and effective in selected patients with omPCa at PSMA PET.

Biochemical outcome in metastatic prostate cancer patients following prostate-directed radiotherapy

Background

The role of cytoreductive local radiotherapy (RT) in metastatic prostate cancer (mPCa) has recently been established. This study aimed to evaluate the biochemical outcome of local RT in mPCa.

Methods

This randomised controlled phase III study was conducted at the Clinical Oncology Department, Suez Canal University Hospital. Eligible participants were de-novo or metachronous mPCa patients with Eastern Cooperative Oncology Group performance status of 0-2. Participants were randomised to receive either cytoreductive prostate-directed RT in addition to standard care or standard care alone. The conventional radiation schedule of 70 Gy/35 fractions or the hypofractionated schedule of 55 Gy/20 fractions were delivered. The primary endpoint was biochemical progression-free survival (BPFS), and the secondary endpoint was overall survival (OS). Survival and post-hoc analyses were performed using Cox regression and the Kaplan-Meier method with the log-rank test.

Results

Between 23 November 2020 and 21 2022, 70 patients were enrolled in this study. Of them, 34 patients were assigned to the prostate RT group, and 29 patients were assigned to the control group. At a median follow-up of 12 months, the median BPFS has not been reached for the prostate RT group compared to 4.067 months for the control group (HR: 0.147, p < 0.001). Subgroup analysis showed that the median BPFS was statistically significantly correlated with low-volume (95% CI, 0.004 to 0.262, p = 0·001) and hormonal-sensitive metastatic disease (95% CI, 0.010 to 0.192, p < 0·001). The median OS was 16.33 months for the prostate-RT group compared to 11.33 months for the control group (HR: 0.313, p = 0.003).

Conclusion

Prostate-directed RT improved BPFS and OS in mPCa patients, particularly in those with low volume and hormonal-sensitive disease.

Trial Registration

This trial is registered on (27/4/2023), retrospectively registered with pactr.samrc.ac.za, PACTR202305854600529, URL: https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=25510.

Targeting of H19/cell adhesion molecules circuitry by GSK-J4 epidrug inhibits metastatic progression in prostate cancer

BACKGROUND

About 30% of Prostate cancer (PCa) patients progress to metastatic PCa that remains largely incurable. This evidence underlines the need for the development of innovative therapies. In this direction, the potential research focus might be on long non-coding RNAs (lncRNAs) like H19, which serve critical biological functions and show significant dysregulation in cancer. Previously, we showed a transcriptional down-regulation of H19 under combined pro-tumoral estrogen and hypoxia treatment in PCa cells that, in turn, induced both E-cadherin and β4 integrin expression. H19, indeed, acts as transcriptional repressor of cell adhesion molecules affecting the PCa metastatic properties. Here, we investigated the role of H19/cell adhesion molecules circuitry on in vivo PCa experimental tumor growth and metastatic dissemination models.

METHODS

H19 was silenced in luciferase-positive PC-3 and 22Rv1 cells and in vitro effect was evaluated by gene expression, proliferation and invasion assays before and after treatment with the histone lysine demethylase inhibitor, GSK-J4. In vivo tumor growth and metastasis dissemination, in the presence or absence of GSK-J4, were analyzed in two models of human tumor in immunodeficient mice by in vivo bioluminescent imaging and immunohistochemistry (IHC) on explanted tissues. Organotypic Slice Cultures (OSCs) from fresh PCa-explant were used as ex vivo model to test GSK-J4 effects.

RESULTS

H19 silencing in both PC-3 and 22Rv1 cells increased: i) E-cadherin and β4 integrin expression as well as proliferation and invasion, ii) in vivo tumor growth, and iii) metastasis formation at bone, lung, and liver. Of note, treatment with GSK-J4 reduced lesions. In parallel, GSK-J4 efficiently induced cell death in PCa-derived OSCs.

CONCLUSIONS

Our findings underscore the potential of the H19/cell adhesion molecules circuitry as a targeted approach in PCa treatment. Modulating this interaction has proven effective in inhibiting tumor growth and metastasis, presenting a logical foundation for targeted therapy.

Oncological and perioperative outcomes of surgery with or without metastasis-directed therapy as part of a multimodal treatment in men with de-novo oligometastatic prostate cancer

PURPOSE

To investigate the feasibility, safety, and oncological outcomes of Radical Prostatectomy (RP; either Robot-Assisted [RARP] or Open RP [ORP]) in oligometastatic prostate cancer (omPCa). Additionally, we assessed whether there was an added benefit of metastasis-directed therapy (MDT) in these patients in the adjuvant setting.

METHODS

Overall, 68 patients with omPCa (≤ 5 skeletal lesions at conventional imaging) treated with RP and pelvic lymph node dissection between 2006 and 2022 were included. Additional therapies (androgen deprivation therapy [ADT] and MDT) were administered according to the treating physicians' judgment. MDT was defined as metastasis surgery/radiotherapy within 6 months of RP. We assessed Clinical Progression (CP), Biochemical Recurrence (BCR), post-operative complications and overall mortality (OM) of RP and the impact of adjuvant MDT + ADT versus RP + ADT alone.

RESULTS

Median follow-up was 73 months (IQR 62-89). RARP reduced the risk of severe complications after adjusting for age and CCI (OR 0.15; p = 0.02). After RP, 68% patients were continent. Median 90-days PSA after RP was 0.12 ng/dL. CP and OM-free survival at 7 years were 50% and 79%, respectively. The 7-years OM-free survival rates were 93 vs. 75% for men treated with vs. without MDT (p = 0.04). At regression analyses, MDT after surgery was associated with a 70% decreased mortality rate (HR 0.27, p = 0.04).

CONCLUSIONS

RP appeared to represent a safe and feasible option in omPCa. RARP reduced the risk of severe complications. Integrating MDT with surgery in the context of a multimodal treatment might improve survival in selected omPCa patients.

Zn2+-interference and H2S-mediated gas therapy based on ZnS-tannic acid nanoparticles synergistic enhancement of cell apoptosis for specific treatment of prostate cancer

Zn²⁺ and H₂S are essential to maintain normal prostate function, and sometimes can evolve into weapons to attack and destroy prostate cancer (PCa) cells. Nevertheless, how to achieve the targeted and effective release of Zn²⁺ and H₂S, and reverse the concentration distribution within PCa tumor cells still highly challenging. Herein, combined with these pathological characteristics of prostate, we proposed a tumor microenvironment (TME) responsive Zn²⁺-interference and H₂S-mediated gas synergistic therapy strategy based on a nanoplatform of tannic acid (TA) modified zinc sulfide nanoparticles (ZnS@TA) for the specific treatment of PCa. Once the constructed pH-responsive ZnS@TA internalized by cancer cells, it would instantaneously decomposed in acidic TME, and explosively release excess Zn²⁺ and H₂S exceeding the cell self-regulation threshold. Meanwhile, the in situ produced Zn²⁺ and H₂S synergistic enhancement of cell apoptosis, which is evidenced to increase levels of Bax and Bax/Bcl-2 ratio, release of Cytochrome c in cancer cells, contributing to inhibit the growth of tumor. Moreover, the TA in cooperation with Zn²⁺ specifically limits the migration and invasion of PCa cells. Both in vitro and in vivo results demonstrate that the Zn²⁺-interference in combination with H₂S-mediated gas therapy achieves an excellent anti-tumor performance. Overall, this nanotheranostic synergistic therapy provides a promising direction for exploring new strategies for cancer treatment based on specific tumor pathological characteristics, and provides a new vision for promoting practical cancer therapy.

Development and validation of a novel risk model in newly diagnosed de novo bone metastatic prostate cancer (M1b): a retrospective study

Background

Previous studies suggested that bone metastasis has a significant effect on the time of progression to metastatic castration-resistant prostate cancer (CRPC) for newly diagnosed de novo bone metastatic hormone-sensitive prostate cancer (mHSPC). Nevertheless, the effect of different bone metastasis sites was not fully evaluated. This study aimed to develop and validate a novel bone metastatic risk model.

Methods

We enrolled 122 patients who were newly diagnosed with de novo bone metastatic prostate cancer following primary androgen deprivation based therapy at our institution from January 2008 to June 2021. The metastatic bone sites were classified into six sites: skull; cervical, thoracic, and lumbar vertebrae; chest (ribs and sternum); pelvis; upper limbs; and lower limbs. We calculated the bone metastatic score (BMS) for each site: 0 points were assigned for non-metastasis and 1 point was assigned for metastasis. The X-tile was adopted to acquire optimal cutoff points of BMS. We defined high-risk group (HRG) as BMS ≥ 3 and low-risk group (LRG) as BMS < 3. The new bone risk stratification was validated by calculating the area under the receiver operating characteristic curve (AUC). Subsequently, the relevant clinical prognostic variables were added to construct a predictive nomogram for predicting CRPC.

Results

The median patient age was 73 years. Most patients had Gleason score ≤8 (93 cases, 76.2%). The median follow-up duration was 11.5 months (range: 2-92 months). Eighty-six patients progressed to CRPC during the follow-up. The most common bone metastatic site was the pelvis (90.2%). The median BMS was 4. Seventy-six patients had HRG, while forty-six had LRG. The 1-, 2-, and 3-year AUCs for H/LRG were 0.620, 0.754, and 0.793, respectively. The HRG was associated with earlier time to CRPC. A nomogram based on four parameters (Gleason score, H/LRG, prostate-specific antigen [PSA] nadir, and time to PSA nadir) was developed to predict CRPC. Internal validation using bootstrapping demonstrated good accuracy for predicting the CRPC (C-index: 0.727). The calibration analysis demonstrated that the model performed well.

Conclusion

We established a novel H/LRG risk model for newly diagnosed de novo bone metastatic prostate cancer, which provided evidence to support clinical decision-making.

Molecular Mechanisms of Noncoding RNA in the Occurrence of Castration-Resistant Prostate Cancer

Although several therapeutic options have been shown to improve survival of most patients with prostate cancer, progression to castration-refractory state continues to present challenges in clinics and scientific research. As a highly heterogeneous disease entity, the mechanisms of castration-resistant prostate cancer (CRPC) are complicated and arise from multiple factors. Among them, noncoding RNAs (ncRNAs), the untranslated part of the human transcriptome, are closely related to almost all biological regulation, including tumor metabolisms, epigenetic modifications and immune escape, which has encouraged scientists to investigate their role in CRPC. In clinical practice, ncRNAs, especially miRNAs and lncRNAs, may function as potential biomarkers for diagnosis and prognosis of CRPC. Therefore, understanding the molecular biology of CRPC will help boost a shift in the treatment of CRPC patients. In this review, we summarize the recent findings of miRNAs and lncRNAs, discuss their potential functional mechanisms and highlight their clinical application prospects in CRPC.

Identification of ZDHHC1 as a Pyroptosis Inducer and Potential Target in the Establishment of Pyroptosis-Related Signature in Localized Prostate Cancer

Pyroptosis or cellular inflammatory necrosis is a programmed cell death kind. Accumulating evidence shows that pyroptosis plays a crucial role in the invasion, metastasis, and proliferation of tumor cells, thus affecting the prognosis of tumors and therapeutic effects. Prostate cancer (PCa), a common malignancy among men, is associated with inflammation. Pathophysiological effects of pyroptosis on tumor development and progression, as well as the mediation of PCa, are known, but its effects on the potential prognosis for PCa warrant in-depth investigation. Herein, we built a risk model of six pyroptosis-related genes and verified their predictive abilities for prognostic and therapeutic effects. Higher risk scores indicated a higher probability of biochemical recurrence (BCR), higher immune infiltration, and worsened clinicopathological features. To derive scientific and reliable predictions for BCR in patients having PCa, the findings of the current study were verified in the Gene Expression Omnibus (GEO) cohort following evaluation in The Cancer Genome Atlas (TCGA) dataset. Additionally, after evaluating the six genes in the model, ZDHHC1 was found to be an important component. Its antitumor role was further assessed through in vivo and in vitro experiments, and its promoting effect on pyroptosis was further evaluated and verified. The above results provided a new perspective for further studies on pyroptosis and its clinical utility for PCa.

The current role of precision surgery in oligometastatic prostate cancer

Oligometastatic prostate cancer (omPCa) is a novel intermediate disease state characterized by a limited volume of metastatic cells and specific locations. Accurate staging is paramount to unmask oligometastatic disease, as provided by prostate-specific membrane antigen-positron emission tomography. Driven by the results of prospective trials employing conventional and/or modern staging modalities, the treatment landscape of omPCa has rapidly evolved over the last years. Several treatment-related questions comprising the concept of precision strikes are under development. For example, beyond systemic therapy, cohort studies have found that cytoreductive radical prostatectomy (CRP) can confer a survival benefit in select patients with omPCa. More importantly, CRP has been consistently shown to improve long-term local symptoms when the tumor progresses across disease states due to resistance to systemic therapies. Metastasis-directed treatments have also emerged as a promising treatment option due to the visibility of oligometastatic disease and new technologies as well as treatment strategies to target the novel PCa colonies. Whether metastases are present at primary cancer diagnosis or detected upon biochemical recurrence after treatment with curative intent, targeted yet decisive elimination of disseminated tumor cell hotspots is thought to improve survival outcomes. One such strategy is salvage lymph node dissection in oligorecurrent PCa which can alter the natural history of progressive PCa. In this review, we will highlight how refinements in modern staging modalities change the classification and treatment of (oligo-)metastatic PCa. Further, we will also discuss the current role and future directions of precision surgery in omPCa.

Advancements in the treatment of metastatic hormone-sensitive prostate cancer

In the last decade, there have been substantial improvements in the outcome of the management of metastatic hormone-sensitive prostate cancer (mHSPC) following the development of several novel agents as well as by combining several therapeutic strategies. Although the overall survival (OS) of mHSPC is shown to improve with intense androgen deprivation therapy (ADT), combined with docetaxel, as well as other novel hormonal therapy agents, or alongside local intervention to the primary neoplasm. Notably, luteinizing hormone-releasing hormone (LHRH) antagonists are known to cause fewer cardiovascular side effects compared with LHRH agonists. Thus, in this mini review, we explore the different approaches in the management of mHSPC, with the aim that we may provide useful information for both basic scientists and clinicians when managing relevant clinical situations.

Magnetic Resonance Imaging and Targeted Biopsies Compared to Transperineal Mapping Biopsies Before Focal Ablation in Localised and Metastatic Recurrent Prostate Cancer After Radiotherapy

BACKGROUND

Recurrent prostate cancer after radiotherapy occurs in one in five patients. The efficacy of prostate magnetic resonance imaging (MRI) in recurrent cancer has not been established. Furthermore, high-quality data on new minimally invasive salvage focal ablative treatments are needed.

OBJECTIVE

To evaluate the role of prostate MRI in detection of prostate cancer recurring after radiotherapy and the role of salvage focal ablation in treating recurrent disease.

DESIGN, SETTING, AND PARTICIPANTS

The FORECAST trial was both a paired-cohort diagnostic study evaluating prostate multiparametric MRI (mpMRI) and MRI-targeted biopsies in the detection of recurrent cancer and a cohort study evaluating focal ablation at six UK centres. A total of 181 patients were recruited, with 155 included in the MRI analysis and 93 in the focal ablation analysis.

INTERVENTION

Patients underwent choline positron emission tomography/computed tomography and a bone scan, followed by prostate mpMRI and MRI-targeted and transperineal template-mapping (TTPM) biopsies. MRI was reported blind to other tests. Those eligible underwent subsequent focal ablation. An amendment in December 2014 permitted focal ablation in patients with metastases.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Primary outcomes were the sensitivity of MRI and MRI-targeted biopsies for cancer detection, and urinary incontinence after focal ablation. A key secondary outcome was progression-free survival (PFS).

RESULTS AND LIMITATIONS

Staging whole-body imaging revealed localised cancer in 128 patients (71%), with involvement of pelvic nodes only in 13 (7%) and metastases in 38 (21%). The sensitivity of MRI-targeted biopsy was 92% (95% confidence interval [CI] 83-97%). The specificity and positive and negative predictive values were 75% (95% CI 45-92%), 94% (95% CI 86-98%), and 65% (95% CI 38-86%), respectively. Four cancer (6%) were missed by TTPM biopsy and six (8%) were missed by MRI-targeted biopsy. The overall MRI sensitivity for detection of any cancer was 94% (95% CI 88-98%). The specificity and positive and negative predictive values were 18% (95% CI 7-35%), 80% (95% CI 73-87%), and 46% (95% CI 19-75%), respectively. Among 93 patients undergoing focal ablation, urinary incontinence occurred in 15 (16%) and five (5%) had a grade ≥3 adverse event, with no rectal injuries. Median follow-up was 27 mo (interquartile range 18-36); overall PFS was 66% (interquartile range 54-75%) at 24 mo.

CONCLUSIONS

Patients should undergo prostate MRI with both systematic and targeted biopsies to optimise cancer detection. Focal ablation for areas of intraprostatic recurrence preserves continence in the majority, with good early cancer control.

PATIENT SUMMARY

We investigated the role of magnetic resonance imaging (MRI) scans of the prostate and MRI-targeted biopsies in outcomes after cancer-targeted high-intensity ultrasound or cryotherapy in patients with recurrent cancer after radiotherapy. Our findings show that these patients should undergo prostate MRI with both systematic and targeted biopsies and then ablative treatment focused on areas of recurrent cancer to preserve their quality of life. This trial is registered at ClinicalTrials.gov as NCT01883128.

Short-Term Outcomes and Clinical Efficacy of Stereotactic Body Radiation Therapy (SBRT) for Oligometastases of Prostate Cancer in China

Objective

To assess the efficacy and safety of stereotactic body radiation therapy (SBRT) in managing oligometastases of prostate cancer. Moreover, it is the largest-to-date study in China to report the safety and efficacy of SBRT by CyberKnife for oligometastases of prostate cancer.

Methods

In this retrospective study, 75 patients with 108 oligometastases were treated by SBRT from May 2012 to February 2021. Among these patients, 43 patients were treated with the intention to control all known metastatic lesions and 32 were treated for palliative care. Patients received regular follow-up evaluations every 3 months. Efficacy was assessed based on local control (LC) rates, biochemical progression-free survival (bPFS), progression-free survival (PFS), and overall survival (OS). Safety was assessed based on clinical adverse events.

Results

Median follow-up time was 23.2 months (1.2-106.9 months). The complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) rates were 63.0%, 10.2%, 21.3% and 5.6%, respectively. The 6-month, 1-, and 2-year LC rates were 100%, 97.5%, and 96.0% respectively while the 6-month, 1-, and 2-year bPFS rates were 74.6%, 53.3%, and 47.9%, respectively. Additionally, 6-month, 1-, and 2-year PFS rates were 77.5%, 50.8%, and 47.2%, respectively. The 6-month, 1-, and 2-year OS rates were 97.0%, 88.8%, and 87.0%, respectively. For the 15 metastatic castration-resistant prostate cancer (mCRPC) patients with 23 lesions, the 2-year LC rates were 93.8%, while for 60 metastatic hormone-sensitive prostate cancer (mHSPC) patients with 85 lesions, the 2-year LC rates were 96.7%. No predictors of LC were found after univariate analysis. In those not on androgen deprivation therapy (ADT; n = 27), the 2-year freedom from ADT was 44.0%. All of the 24 patients with oligmetastase-induced complications experienced varying degrees of alleviation after SBRT. The treatment was well tolerated. No grade 3 or higher toxicity was observed.

Conclusion

SBRT is a safe and effective treatment modality in the management of oligometastases of mHSPC and mCRPC with high LC rates and acceptable toxicity. SBRT could provide a treatment choice for mCRPC, as well as an alternative to delay the start of ADT for mHSPC.

Cytoreductive prostate cryoablation and metronomic cyclophosphamide for metastatic hormone-sensitive prostate cancer

Aim: This study reports the outcomes of cytoreductive prostate cryoablation and metronomic cyclophosphamide for the treatment of metastatic hormone-sensitive prostate cancer (mHSPC). Methods: Patients with mHSPC from the authors' prostate cancer database who had received cytoreductive prostate cryoablation and metronomic cyclophosphamide were identified retrospectively. Results: Eight consecutive patients were enrolled in the study. All the patients tolerated combination therapy. The median metastatic castration-resistant prostate cancer-free survival was 62.5 months. Seven patients (87.5%) had a prostate-specific antigen nadir <0.1 ng/ml. Dysuria and hematuria before prostate cryoablation disappeared within 1 month after cryosurgery, and no incontinence was seen after prostate cryoablation. No local therapy was needed during follow-up. Conclusion: Cytoreductive prostate cryoablation and metronomic cyclophosphamide prove an effective and safe combination therapy for mHSPC.

Narrative review of local prostate and metastasis-directed radiotherapy in the treatment of metastatic prostate cancer

The role of local treatment in patients with de novo metastatic prostate cancer is controversial. In population-based retrospective studies, metastatic prostate cancer patients who received local treatment with prostate radiotherapy showed a better prognosis than those who did not. In addition, several prospective randomized studies demonstrated that prostate radiotherapy achieves a survival benefit for patients with oligo-metastasis. Moreover, the efficacy of metastasis-directed radiotherapy was evaluated, revealing a potential benefit for patients with oligo-metastasis. Importantly, these radiotherapies may reduce the occurrence of symptomatic local events. In this review, the rationale, efficacy and future perspectives for local prostate and metastasis-directed radiotherapy in the treatment of metastatic prostate cancer were described and summarized.

A ‘real-world’ standard for radical prostatectomy: Analysis of the British Association of Urological Surgeons Complex Operations Reports, 2016–2018

Objective:

To produce comprehensive and detailed benchmarking data allowing surgeons and patients to compare practice against, by using all recorded radical prostatectomies across a 3-year period in England.

Patients and methods:

The British Association of Urological Surgeons (BAUS) manages the radical prostatectomy (RP) Complex Operations Database. Surgical departments upload data which they can review and amend before lockdown and data cleansing. Analysis of 2016–2018 data held on the BAUS Complex Operations Database was performed for 21,973 patients undergoing RP in England, producing procedure-specific benchmarking data. General linear models were used to assess differences in patient selection between different operative modalities. Analysis involved assessment of case selection, operative decisions and outcomes, case volume and pathological outcomes.

Results:

Using national Hospital Episode Statistics, the BAUS RP dataset was estimated 91% complete. Median age was 65 and 96% were American Society of Anesthesiologists (ASA) Grades 1–2. Over 80% had RP performed in a high-volume centre (>100 annual RPs) and 88% had Gleason grade group (GGG) ⩾2 disease on biopsy. Robotic-assisted RP (RARP), laparoscopic RP (LRP) and open RP (ORP) were performed in 85%, 7.2% and 7.7% of cases, respectively. Patient and disease characteristics differed across surgical modalities. Transfusion rates were 0.14% in RARP, 0.38% in LRP and 1.8% in ORP. Increased positive surgical margin (PSM) rates were observed with increasing prostate-specific antigen (PSA), GGG and T-stage, with comparable PSM rates across surgical modalities. Lymph node dissection was performed more commonly in high-risk cases (cT3, PSA > 20, GGG ⩾ 4). Pathological upstaging was common. Median length of stay was 1, 2 and 3 days for RARP, LRP and ORP, respectively. ORP had Clavien–Dindo complications ⩾3 and unplanned hospital readmissions.

Conclusion:

This analysis has enabled the first set of UK national RP standards to be produced allowing procedure, patient and disease-specific national, centre and individual comparisons. The present degree of service centralisation, operative modalities, and specific aspects of surgical practice can be observed.

Level of evidence:

2b

A Systematic Review of Patients' Values, Preferences, and Expectations for the Treatment of Metastatic Prostate Cancer

CONTEXT

Advances in systemic agents have increased overall survival for men diagnosed with metastatic prostate cancer. Additional cytoreductive prostate treatments and metastasis-directed therapies are under evaluation. These confer toxicity but may offer incremental survival benefits. Thus, an understanding of patients' values and treatment preferences is important for counselling, decision-making, and guideline development.

OBJECTIVE

To perform a systematic review of patients' values, preferences, and expectations regarding treatment of metastatic prostate cancer.

EVIDENCE ACQUISITION

The MEDLINE, Embase, and CINAHL databases were systematically searched for qualitative and preference elucidation studies reporting on patients' preferences for treatment of metastatic prostate cancer. Certainty of evidence was assessed using Grading of Recommendation, Assessment, Development and Evaluation (GRADE) or GRADE Confidence in the Evidence from Reviews of Qualitative Research (CERQual). The protocol was registered on PROSPERO as CRD42020201420.

EVIDENCE SYNTHESIS

A total of 1491 participants from 15 studies met the prespecified eligibility for inclusion. The study designs included were discrete choice experiments (n = 5), mixed methods (n = 3), and qualitative methods (n = 7). Disease states reported per study were: metastatic castration-resistant prostate cancer in nine studies (60.0%), metastatic hormone-sensitive prostate cancer in two studies (13.3%), and a mixed cohort in four studies (26.6%). In quantitative preference elicitation studies, patients consistently valued treatment effectiveness and delay in time to symptoms as the two top-ranked treatment attributes (low or very low certainty). Patients were willing to trade off treatment-related toxicity for potential oncological benefits (low certainty). In qualitative studies, thematic analysis revealed cancer progression and/or survival, pain, and fatigue as key components in treatment decisions (low or very low certainty). Patients continue to value oncological benefits in making decisions on treatments under qualitative assessment.

CONCLUSIONS

There is limited understanding of how patients make treatment and trade-off decisions following a diagnosis of metastatic prostate cancer. For appropriate investment in emerging cytoreductive local tumour and metastasis-directed therapies, we should seek to better understand how this cohort weighs the oncological benefits against the risks.

PATIENT SUMMARY

We looked at how men with advanced (metastatic) prostate cancer make treatment decisions. We found that little is known about patients' preferences for current and proposed new treatments. Further studies are required to understand how patients make decisions to help guide the integration of new treatments into the standard of care.

Metastatic prostate cancer men's attitudes towards treatment of the local tumour and metastasis evaluative research (IP5-MATTER): protocol for a prospective, multicentre discrete choice experiment study

INTRODUCTION

Systemic therapy with androgen deprivation therapy (ADT) and intensification with agents such as docetaxel, abiraterone acetate and enzalutamide has resulted in improved overall survival in men with de novo synchronous metastatic hormone-sensitive prostate cancer (mHSPC). Novel local cytoreductive treatments and metastasis-directed therapy are now being evaluated. Such interventions may provide added survival benefit or delay the requirement for further systemic agents and associated toxicity but can confer additional harm. Understanding men's preferences for treatment options in this disease state is crucial for patients, clinicians, carers and future healthcare service providers.

METHODS

Using a prospective, multicentre discrete choice experiment (DCE), we aim to determine the attributes associated with treatment that are most important to men with mHSPC. Furthermore, we plan to determine men's preferences for, and trade-offs between, the attributes (survival and side effects) of different treatment options including systemic therapy, local cytoreductive approaches (external beam radiotherapy, cytoreductive radical prostatectomy or minimally invasive ablative therapy) and metastases-directed therapies (metastasectomy or stereotactic ablative body radiotherapy). All men with newly diagnosed mHSPC within 4 months of commencing ADT and WHO performance status 0-2 are eligible. Men who have previously consented to a cytoreductive treatment or have developed castrate-resistant disease will be excluded. This study includes a qualitative analysis component, with patients (n=15) and healthcare professionals (n=5), to identify and define the key attributes associated with treatment options that would warrant trade-off evaluation in a DCE. The main phase component planned recruitment is 300 patients over 1 year, commencing in January 2021, with planned study completion in March 2022.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Health Research Authority East of England, Cambridgeshire and Hertfordshire Research Ethics Committee (Reference: 20/EE/0194). Project information will be reported on the publicly available Imperial College London website and the Heath Economics Research Unit (HERU website including the HERU Blog). We will use the social media accounts of IP5-MATTER, Imperial Prostate London, HERU and the individual researchers to disseminate key findings following publication. Findings from the study will be presented at national/international conferences and peer-reviewed journals. Authorship policy will follow the recommendations of the International Committee of Medical Journal Editors.

TRIAL REGISTRATION NUMBER

NCT04590976.

Upregulation of ATP Binding Cassette Subfamily C Member 5 facilitates Prostate Cancer progression and Enzalutamide resistance via the CDK1-mediated AR Ser81 Phosphorylation Pathway

The treatment of advanced prostate cancer, castration-resistant prostate cancer, remains challenging. The mechanisms of action of ATP binding cassette subfamily C member 5 (ABCC5) in prostate cancer and its relationship with drug resistance are still unclear. Expression and prognostic analyses of ABCC5 were performed through bioinformatic methods and immunohistochemistry analyses in multiple public databases as well as in our own prostate cancer cohort. The biological function of ABCC5 in prostate cancer cells was evaluated by in vitro and in vivo cell proliferation and migration and invasion assays. The regulation of CDK1 by ABCC5 was determined via RT-qPCR, western blots, and immunofluorescence. ABCC5 was significantly overexpressed in prostate cancer and positively associated with unfavorable clinicopathological features and prognosis. Upregulation of ABCC5 could enhance the cell proliferation, migration, and invasion of prostate cancer in vitro and in vivo. Mechanistically, ABCC5 exerts a protumor effect by binding to and inhibiting the protein degradation of CDK1, which promotes the phosphorylation of AR at Ser81 by CDK1 and activates the transcriptional activity of AR on target genes. Moreover, the addition of a CDK1 inhibitor or knockdown of CDK1 significantly improved the efficacy of enzalutamide on prostate cancer cells. The ABCC5-CDK1-AR regulatory pathway could be a potential therapeutic target for advanced prostate cancer, especially castration-resistant prostate cancer (CRPC), to enhance the therapeutic effect of enzalutamide.

Optimizing the diagnosis and management of ductal prostate cancer

Ductal adenocarcinoma (DAC) is the most common variant histological subtype of prostate carcinoma and has an aggressive clinical course. DAC is usually characterized and treated as high-risk prostatic acinar adenocarcinoma (PAC). However, DAC has a different biology to that of acinar disease, which often poses a challenge for both diagnosis and management. DAC can be difficult to identify using conventional diagnostic modalities such as serum PSA levels and multiparametric MRI, and the optimal management for localized DAC is unknown owing to the rarity of the disease. Following definitive therapy for localized disease with radical prostatectomy or radiotherapy, the majority of DACs recur with visceral metastases at low PSA levels. Various systemic therapies that have been shown to be effective in high-risk PAC have limited use in treating DAC. Although current understanding of the biology of DAC is limited, genomic analyses have provided insights into the pathology behind its aggressive behaviour and potential future therapeutic targets.

Clinical characteristics and survival outcomes in patients with a high PSA and non-metastatic prostate cancer

BACKGROUND/PURPOSE

To investigate the clinical presentation and survival outcomes of patients with both a high prostate-specific antigen (PSA) value and non-metastatic prostate cancer (PC).

METHODS

In total, 2053 PC patients were managed in our institute between January 2008 and December 2014. A total of 343 (16.7%) patients who presented with PSA values > 100 ng/mL were enrolled. Non-metastatic and metastatic PC were identified in 67 (group 1) and 276 (group 2) patients, respectively. Furthermore, 75 metastatic PC patients with PSA values < 20 ng/mL were included (group 3) for comparison. All demographics and survival outcomes were retrospectively reviewed by a questionnaire.

RESULTS

Group 2 patients had a higher PSA level than did group 1 (median: 1095 vs. 283 ng/mL, p < 0.001), and a higher Gleason grade than did groups 1 and 3 (grade group 4 plus 5: 60%, 77%, and 56%, for groups 1, 2, and 3, respectively; p < 0.001). Other demographics were similar among groups. Group 1 patients survived significantly longer than group 2 and 3 in terms of overall and cancer-specific survival rates (5-year overall survival rates: 87.5%, 46.3%, and 66.9%; 5-year cancer-specific survival rates: 94.7%, 52.7%, and 68.7% for groups 1, 2, and 3, respectively). Group 1 patients receiving local definitive treatments, such as radiation therapy or cryoablation, received survival and metastasis-free benefits compared to those without local treatment.

CONCLUSION

Patients with a high PSA value were not destined to have metastatic PC. Non-metastatic PC patients with a high PSA level obtained a survival benefit from local prostate-definitive treatments.

Additional Treatments to the Local tumour for metastatic prostate cancer-Assessment of Novel Treatment Algorithms (IP2-ATLANTA): protocol for a multicentre, phase II randomised controlled trial

INTRODUCTION

Survival in men diagnosed with de novo synchronous metastatic prostate cancer has increased following the use of upfront systemic treatment, using chemotherapy and other novel androgen receptor targeted agents, in addition to standard androgen deprivation therapy (ADT). Local cytoreductive and metastasis-directed interventions are hypothesised to confer additional survival benefit. In this setting, IP2-ATLANTA will explore progression-free survival (PFS) outcomes with the addition of sequential multimodal local and metastasis-directed treatments compared with standard care alone.

METHODS

A phase II, prospective, multicentre, three-arm randomised controlled trial incorporating an embedded feasibility pilot. All men with new histologically diagnosed, hormone-sensitive, metastatic prostate cancer, within 4 months of commencing ADT and of performance status 0 to 2 are eligible. Patients will be randomised to Control (standard of care (SOC)) OR Intervention 1 (minimally invasive ablative therapy to prostate±pelvic lymph node dissection (PLND)) OR Intervention 2 (cytoreductive radical prostatectomy±PLND OR prostate radiotherapy±pelvic lymph node radiotherapy (PLNRT)). Metastatic burden will be prespecified using the Chemohormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease (CHAARTED) definition. Men with low burden disease in intervention arms are eligible for metastasis-directed therapy, in the form of stereotactic ablative body radiotherapy (SABR) or surgery. Standard systemic therapy will be administered in all arms with ADT±upfront systemic chemotherapy or androgen receptor agents. Patients will be followed-up for a minimum of 2 years.

PRIMARY OUTCOME

PFS. Secondary outcomes include predictive factors for PFS and overall survival; urinary, sexual and rectal side effects. Embedded feasibility sample size is 80, with 918 patients required in the main phase II component. Study recruitment commenced in April 2019, with planned follow-up completed by April 2024.

ETHICS AND DISSEMINATION

Approved by the Health Research Authority (HRA) Research Ethics Committee Wales-5 (19/WA0005). Study results will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03763253; ISCRTN58401737.

Cytoreductive radiotherapy combined with abiraterone in metastatic castration-resistance prostate cancer: a single center experience

Background

To investigate the potential benefit of cytoreductive radiotherapy (cRT) in metastatic castration-resistant prostate cancer (mCRPC) patients receiving abiraterone.

Methods

From February 2014 to February 2019, 149 mCRPC patients treated with abiraterone were identified. Patients receiving cRT before abiraterone failure (AbiRT group) were matched by one-to-two propensity score to patients without cRT before abiraterone failure (non-AbiRT group).

Results

The median follow-up was 23.5 months. Thirty patients (20.1%) were in the AbiRT group, whereas 119 patients (79.9%) were in the non-AbiRT group. The 2-year OS of patients managed by AbiRT and non-AbiRT were 89.5% and 73.5%, respectively (P = 0.0003). On multivariate analysis, only AbiRT (HR 0.17; 95% CI 0.05–0.58; P = 0.004) and prognostic index (HR 2.71; 95% CI 1.37–5.35; P = 0.004) were significant factors. After matching, AbiRT continued to be associated with improved OS (median OS not reached vs. 44.0 months, P = 0.009). Subgroup analysis revealed that patients aged ≤ 65 years (HR 0.09; 95% CI 0.01–0.65; P = 0.018), PSA ≤ 20 ng/mL (HR 0.29; 95% CI 0.09–0.99; P = 0.048), chemotherapy-naïve upon abiraterone treatment (HR 0.20; 95% CI 0.06–0.66; P = 0.008) and in intermediate prognosis groups by COU-AA-301 prognostic index (HR 0.13; 95% CI 0.03–0.57; P = 0.007) had improved OS with AbiRT.

Conclusions

cRT before resistance to abiraterone may improve survival in selected mCRPC patients: age ≤ 65 years old, chemotherapy-naïve, with a relatively low PSA level at the diagnosis of mCRPC and intermediate prognosis.

Prostate cryoablation combined with androgen deprivation therapy for newly diagnosed metastatic prostate cancer: a propensity score-based study

BACKGROUND

Several studies showed that androgen deprivation therapy (ADT) plus local treatment of prostate could improve metastatic prostate cancer (mPCa) patients' survival. To date there are few studies analyzed the value of prostate cryoablation in mPCa. The objective of our analysis is to evaluate the oncological results and clinical value of prostate cryoablation combined with ADT compared with ADT alone in newly diagnosed mPCa patients.

METHODS

Newly diagnosed mPCa patients undergoing cryoablation plus ADT (group A) between January 2011 and November 2018 were identified. Patients receiving ADT alone (group B) were selected from the same institutional prostate cancer database by propensity score matching based on clinical characteristics. Oncological results and clinical value in symptom control and primary lesion treatment were compared.

RESULTS

Fifty-four patients were included in each group. Prostate cryoablation was well tolerated. The median follow-up time was 40 (27-53) and 39 (31-54) months in group A and group B, respectively. Patients in group A had a lower median prostate-specific antigen (PSA) nadir (0.025 ng/mL vs. 0.230 ng/mL, p = 0.001), longer median failure-free survival (FFS) (39 months vs. 21 months, p = 0.005), and median metastatic castration-resistant prostate cancer (mCRPC)-free survival (39 months vs. 21 months, p = 0.007). No difference in cancer-specific survival and overall survival was found between the two groups. Multivariate Cox analysis showed combination therapy reduced the risk of FFS by 45.8% (HR = 0.542 [95% CI 0.329-0.893]; p = 0.016). Patients in group A had better clinical relief of urinary symptoms (79.1 vs. 59.1%, p = 0.044) and required less treatment of primary lesions for symptomatic relief (13.0 vs. 31.5%, p = 0.021).

CONCLUSIONS

Prostate cryoablation plus ADT decreases PSA nadir, prolongs FFS and mCRPC-free survival, relieves urinary symptoms and reduces the need for treating primary lesions in newly diagnosed mPCa patients compared to ADT alone.

Targeting Oligometastasis with Stereotactic Ablative Radiation Therapy or Surgery in Metastatic Hormone-sensitive Prostate Cancer: A Systematic Review of Prospective Clinical Trials

CONTEXT

Metastasis-directed therapy (MDT) in the form of stereotactic ablative radiation therapy (SABR), or in combination with surgical metastasectomy, may have a role in cancer control and disease progression.

OBJECTIVE

To perform a systematic review of MDT (surgery or SABR) for oligometastatic (up to 10 metastases, recurrent or de novo) hormone-sensitive prostate cancer in addition to or following primary prostate gland treatment.

EVIDENCE ACQUISITION

Medline, Embase, Cochrane Review Database, and clinical trial Databases were systematically searched for clinical trials reporting oncological outcomes and safety. The risk of bias was assessed with the Cochrane 2.0 or ROBINS-I tool.

EVIDENCE SYNTHESIS

From 1025 articles identified, four clinical trials met the prespecified criteria. These included two randomised and two nonrandomised clinical trials (n=169). Baseline prostate-specific antigen level, age, and metastasis ranged from 2.0 to 17.0 ng/ml, 43 to 75 yr, and one to seven lesions, respectively. Nodal, bone, nodal and bone, and visceral metastases were present in 49.7% (84/169), 33.7% (57/169), 15.9% (27/169), and 0.5% (1/169) of patients, respectively. Diagnostic conventional imaging was used in 43.7% (74/169) and positron emission tomography/computerised tomography in 56.2% (95/169) of patients. SABR and surgical metastasectomy with SABR were used in 78.3% (94/120) and 21.6% (26/120) of patients, respectively. Early progression-free survival ranged from 19% to 60%. Local control was reported as 93-100%. Grade II and III SABR toxicities were reported in 8% (8/100) and 1% (1/100) of patients, respectively. Grade IIIa and IIIb surgical complications were reported in 7.69% (2/26) and 0% (0/26) of patients, respectively.

CONCLUSIONS

MDT is a promising experimental therapeutic approach in men with hormone-sensitive oligometastatic prostate cancer. Randomised comparative studies are required to ascertain its role and optimal timing in oligometastatic recurrence and efficacy in de novo synchronous disease.

PATIENT SUMMARY

We looked at the evidence regarding the use of surgery or radiotherapy at target areas of cancer spread in men with newly diagnosed or relapsed advanced (metastatic) prostate cancer. Evidence supports both treatment options as promising approaches, but further large trials are required.

LncRNA DLX6-AS1 Promotes Malignant Phenotype and Lymph Node Metastasis in Prostate Cancer by Inducing LARGE Methylation

Long non-coding RNAs (lncRNAs) have recently become recognized as crucial players in cancer cellular events including proliferation, migration, and invasion. Herein, we investigated the potential role of lncRNA DLX6-AS1 in prostate cancer cell malignant behaviors and lymph node metastasis. A differentially expressed lncRNA DLX6-AS1 and its downstream regulatory gene (LARGE) were predicted by analysis in silico. RT-qPCR and western blot analysis results demonstrated that DLX6-AS1 was highly expressed, but LARGE was poorly expressed in prostate cancer tissues and cells. The online website indicated that DLX6-AS1 negatively targeted LARGE expression, which was validated by Pearson correlation analysis and MSP. ChIP, RIP, and RNA pull-down assays further suggested that DLX6-AS1 downregulated LARGE expression through recruitment of DNMT1 to its promoter. We induced DLX6-AS1/LARGE overexpression or knockdown to examine their effects through Edu and Transwell assays, which revealed that DLX6-AS1 overexpression accelerated proliferation, invasion, and migration of prostate cancer cells, and that overexpression of LARGE rescued these effects. Tumors xenografts studies confirmed that DLX6-AS1 promoted lymph node metastasis by regulating LARGE, as evidenced by enhanced expression of MMP-9, uPAR, and cathepsin B. In summary, DLX6-AS1 stimulated prostate cancer malignant progression and lymph node metastasis by inducing DNMT1-mediated LARGE methylation, highlighting a potential therapeutic target against prostate cancer.

Advances of Zinc Signaling Studies in Prostate Cancer

Prostate cancer (PCa) is one of the most common cancers and the second leading cause of cancer-related death among men worldwide. Despite progresses in early diagnosis and therapeutic strategies, prognosis for patients with advanced PCa remains poor. Noteworthily, a unique feature of healthy prostate is its highest level of zinc content among all soft tissues in the human body, which dramatically decreases during prostate tumorigenesis. To date, several reviews have suggested antitumor activities of zinc and its potential as a therapeutic strategy of PCa. However, an overview about the role of zinc and its signaling in PCa is needed. Here, we review literature related to the content, biological function, compounds and clinical application of zinc in PCa. We first summarize zinc content in prostate tissue and sera of PCa patients with their clinical relevance. We then elaborate biological functions of zinc signaling in PCa on three main aspects, including cell proliferation, death and tumor metastasis. Finally, we discuss clinical applications of zinc-containing compounds and proteins involved in PCa signaling pathways. Based on currently available studies, we conclude that zinc plays a tumor suppressive role and can serve as a biomarker in PCa diagnosis and therapies.

Clinical perspectives from ongoing trials in oligometastatic or oligorecurrent prostate cancer: an analysis of clinical trials registries

PURPOSE

Thanks to the introduction of more sensitive/specific imaging and minimally invasive treatment techniques, the oligometastatic state in prostate cancer (PCa) has attracted the interest of the uro-oncological community. We aim to identify and analyze trials across five registries to gain insights into the directions this field is moving.

METHODS

A systematic review of trials on oligometastatic PCa registered on ClinicalTrials.gov, ANZCTR, ISRCTN, Netherlands and UMIN Clinical Trials Registries was performed using the following keywords: 'prostate cancer' and 'oligo'. Data were extracted from ongoing/completed trials, with an unreported primary endpoint in a peer-reviewed journal, as of May until August, 2018.

RESULTS

We identified 41 trials on oligometastatic PCa. Twenty-four trials are conducted in North America and 14 in Europe. Up to 70% are phase I or II trials and < 10% (n = 4) are in phase III. Less than 50% (n = 17) are randomized controlled trials. Oligometastases are PET detected in 25 trials. Studies on synchronous oligometastatic (n = 12; 29%) or oligorecurrent (n = 14; 34%) PCa are equally represented, the remainder focus on mixed states (n = 15; 37%). The majority (n = 39; 95%) of trials investigate local treatment options (RP: 5; RT: 9; RP ± RT: 7; metastasis-directed therapy: 28) with (72%) or without (28%) systemic treatment. The remaining two are imaging studies. Progression-free (PFS; 17/41; 41%) or overall survival (OS; 3/41; 7%) is defined as primary endpoint in half of all trials, others are 'safety/toxicity' or 'PSA response'.

CONCLUSIONS

With 41 ongoing trials, there is great interest in oligometastatic PCa. Most trials address local ablative treatments both for prostate and/or metastases, typically by radiotherapy, and several attempts to determine the benefit of adding systemic therapy. The field will hopefully have definitive answers after completion of four ongoing phase III trials.

SREBP1 siRNA enhance the docetaxel effect based on a bone-cancer dual-targeting biomimetic nanosystem against bone metastatic castration-resistant prostate cancer

Until recently, there have been limited options for patients with bone metastatic castration-resistant prostate cancer (BmCRPC) following the failure of or development of resistance to docetaxel (DTX), which is one of the frontline treatments. Sterol regulatory element-binding protein 1 (SREBP1) is reported to regulate abnormal lipid metabolism and to promote the progression and metastasis of prostate cancer (PCa). The siRNA interferes SREBP1 may provide an efficient treatment when combined with DTX. Methods: In this study, lipoic acid (LA) and cross-linked peptide-lipoic acid micelles were cross-linked (LC) for DTX and siSREBP1 delivery (LC/D/siR). Then, cell membrane of PCa cells (Pm) and bone marrow mesenchymal stem cells (Bm) were fused for cloaking LC/D/siR (PB@LC/D/siR). Finally, the synthesized PB@LC/D/siR was evaluated in vitro and in vivo. Results: PB@LC/D/siR is internalized in PCa cells by a mechanism of lysosome escape. Tumor targeting and bone homing studies are evaluated using bone metastatic CRPC (BmCRPC) models, both in vitro and in vivo. Moreover, the enhanced anti-proliferation, anti-migration and anti-invasion capacities of DTX- and siSREBP1- loaded PB@LC (PB@LC/D/siR) were observed in vitro. Furthermore, PB@LC/D/siR was able to suppress the growth of the tumor effectively with deep tumor penetration, high safety and good protection of the bone at the tumor site. Additionally, the mRNA levels and protein levels of SREBP1 and SCD1 were able to be significantly downregulated by PB@LC/D/siR. Conclusion: This study presented a bone-cancer dual-targeting biomimetic nanodelivery system for bone metastatic CRPC.