Chemotherapy in hormone-sensitive metastatic prostate cancer: Evidences and uncertainties from the literature

Multifunctional targeted nanosystem based on aggregation-induced emission: Enhanced synergistic mild-photothermal chemotherapy of prostate cancer via downregulation of heat shock protein 70 under NIR-II imaging

Prostate cancer is the second most common malignancy in men, often presents at advanced stages, where treatment options are limited due to surgical intolerance and resistance to androgen deprivation therapy. Mild photothermal therapy (PTT) at 42-49°C selectively eliminates tumors while sparing normal tissues, but its efficacy is reduced by heat shock protein (HSP70) upregulation, which inhibits apoptosis. To address these limitations, we developed 2TToD@NPs, a multifunctional nanosystem combining second near-infrared (NIR-II) fluorescence imaging, mild PTT, and chemotherapy. The nanosystem, comprising an aggregation-induced emission agent (2TT-oC26B) and doxorubicin (DOX), targets prostate cancer cells via folic acid modification. Upon laser irradiation, 2TT-oC26B generates strong NIR-II fluorescence and thermal energy for imaging and mild PTT. Concurrently, DOX enhances tumor sensitivity to PTT by downregulating HSP70, reduces thermal resistance, induces DNA damage, and generates reactive oxygen species, triggering apoptosis. This synergistic approach overcomes the limitations of single-modality therapies. Our findings suggest that the multifunctional nanosystem effectively integrate precise imaging and targeted therapy, offering a promising strategy for advanced prostate cancer diagnosis and treatment.

Recommendations on the treatment of metastatic hormone-sensitive prostate cancer: Patient selection

The standard treatment for metastatic hormone-sensitive prostate cancer (mHSPC) is now a combination of androgen deprivation therapy plus an androgen receptor-targeted therapy (abiraterone, apalutamide, enzalutamide or darolutamide), with or without chemotherapy (docetaxel). The selection of suitable patients for each therapeutic approach has become a determining factor to ensure efficacy and minimize side effects. This article combines recent clinical evidence with the accumulated experience of experts in medical oncology, radiation oncology and urology, to provide a comprehensive view and therapeutic recommendations for mHSPC.

Targeted Ultrasound Nanobubbles Therapy for Prostate Cancer via Immuno-Sonodynamic Effect

Background

Prostate cancer (PCa) poses a significant global health threaten. Immunotherapy has emerged as a novel strategy to augment the inhibition of tumor proliferation. However, the sole use of anti-PD-L1 Ab for PCa has not yielded improvements, mirroring outcomes observed in other tumor types.

Methods

This study employed the thin film hydration method to develop lipid nanobubbles (NBs) encapsulating chlorin e6 (Ce6) and anti-PD-L1 Ab (Ce6@aPD-L1 NBs). Our experimental approach included cellular assays and mouse immunization, providing a comprehensive evaluation of Ce6@aPD-L1 NBs' impact.

Results

The Ce6@aPD-L1 NBs effectively induced reactive oxygen species generation, leading to tumor cells death. In mice, they demonstrated a remarkable enhancement of immune responses compared to control groups. These immune responses encompassed immunogenic cell death induced by sonodynamic therapy and PD-1/PD-L1 blockade, activating dendritic cells maturation and effectively stimulating CD8+T cells.

Conclusion

Ce6@aPD-L1 NBs facilitate tumor-targeted delivery, activating anti-tumor effects through direct sonodynamic therapy action and immune system reactivation in the tumor microenvironment. Ce6@aPD-L1 NBs exhibit substantial potential for achieving synergistic anti-cancer effects in PCa.

A mixed-apoptotic effect of Jurinea mesopotamica extract on prostate cancer cells: a promising source for natural chemotherapeutics

This research investigates the potential use of Jurinea mesopotamica Hand.-Mazz. (Asteraceae) in cancer treatment. In this study, a plant extract was prepared using all parts of J. mesopotamica, and its effect on the proliferation of cancer and normal cells was tested using the MTT method. It was found to have a selective cytotoxic effect on prostate cancer cells, with the lowest IC50 (half-maximal inhibitory concentration) of 10μg/mL found in the butanol extract (JMBE). The extract suppressed the proliferation of prostate cancer cells (67 %), disrupted organelle integrity (49 %), increased reactive oxidative stress (66 %), and triggered cell death (51 %). In addition, apoptotic gene expressions and protein levels increased, and the profile of amino acids related to energy metabolism was elevated. Based on LC-MS/MS results, the plant contained higher levels of flavonoids, including isoquercitrin, cosmosiin, astragalin, nicotiflorin, luteolin, and apigenin. These results suggest that J. mesopotamica has a selective effect on prostate cancer due to its high flavonoid content and might be a promising natural alternative for cancer treatment.

Redox State Modulatory Activity and Cytotoxicity of Olea europaea L. (Oleaceae) Leaves Extract Enriched in Polyphenols Using Macroporous Resin

The food products derived from Olea europaea are a fundamental part of the Mediterranean diet, and their health-promoting effects are well known. In this study, we analyzed the phytochemical characteristics, the redox state modulatory activity, and the cytotoxic effect of an olive leaf aqueous extract enriched by macroporous resin on different tumor and normal cell lines (LNCaP, PC3, HFF-1). HPLC-DAD analysis, the Folin-Ciocalteu and aluminum chloride methods confirmed the qualitatively and quantitatively high content of phenolic compounds (130.02 ± 2.3 mg GAE/g extract), and a DPPH assay (IC50 = 100.00 ± 1.8 μg/mL), the related antioxidant activity. The biological investigation showed a significant cytotoxic effect, highlighted by an MTT test and the evident cellular morphological changes, on two prostate cancer cell lines. Remarkably, the extract was practically non-toxic on HFF-1 at the concentrations (100, 150, 300 µg/mL) and exposure times tested. Hence, the results are selective for tumor cells. The underlying cytotoxicity was associated with the decrease in ROS production (55% PC3, 42% LNCaP) and the increase in RSH levels (>50% PC3) and an LDH release assay (50% PC3, 40% LNCaP, established necrosis as the main cell death mechanism.

Development and validation of a nomogram to predict cancer-specific survival in nonsurgically treated elderly patients with prostate cancer

Prostate Cancer (PC) is the most common male nonskin tumour in the world, and most diagnosed patients are over 65 years old. The main treatment for PC includes surgical treatment and nonsurgical treatment. Currently, for nonsurgically treated elderly patients, few studies have evaluated their prognostic factors. Our aim was to construct a nomogram that could predict cancer-specific survival (CSS) in nonsurgically treated elderly PC patients to assess their prognosis-related independent risk factors. Patient information was obtained from the Surveillance, Epidemiology and End Results (SEER) database, and our target population was nonsurgically treated PC patients who were over 65 years old. Independent risk factors were determined using both univariate and multivariate Cox regression models. A nomogram was built using a multivariate Cox regression model. The accuracy and discrimination of the prediction model were tested using the consistency index (C-index), the area under the subject operating characteristic curve (AUC), and the calibration curve. Decision curve analysis (DCA) was used to examine the potential clinical value of this model. A total of 87,831 elderly PC patients with nonsurgical treatment in 2010-2018 were included in the study and were randomly assigned to the training set (N = 61,595) and the validation set (N = 26,236). Univariate and multivariate Cox regression model analyses showed that age, race, marital status, TNM stage, chemotherapy, radiotherapy modality, PSA and GS were independent risk factors for predicting CSS in nonsurgically treated elderly PC patients. The C-index of the training set and the validation set was 0.894 (95% CI 0.888-0.900) and 0.897 (95% CI 0.887-0.907), respectively, indicating the good discrimination ability of the nomogram. The AUC and the calibration curves also show good accuracy and discriminability. We developed a new nomogram to predict CSS in elderly PC patients with nonsurgical treatment. The model is internally validated with good accuracy and reliability, as well as potential clinical value, and can be used for clinical aid in decision-making.

Survival Trend in Individuals With De Novo Metastatic Prostate Cancer After the Introduction of Doublet Therapy

Importance

Recently, life-prolonging treatments for patients with advanced prostate cancer have been introduced in clinical practice.

Objective

To investigate if the introduction of doublet therapy is associated with changes in survival on a population-basis.

Design, Setting, and Participants

This nationwide population-based cohort study used data from the Prostate Cancer data Base Sweden from 2008 to 2020. Men registered with de novo metastatic castration-sensitive prostate cancer (mCSPC) were included.

Exposure

The proportion of men with mCSPC who received doublet therapy, ie, androgen deprivation therapy plus androgen receptor pathway inhibitor drugs or chemotherapy was assessed.

Main Outcomes and Measures

Standardized overall survival, taking age, comorbidity, and cancer characteristics into consideration, was estimated by use of a parametric survival model.

Results

A total of 11 382 men were included in this study (median [IQR] age, 74.0 [68-81] years). There was a shift toward less advanced prostate cancer during the study period with a decrease in median (IQR) prostate-specific antigen at diagnosis in men with mCSPC from 145 (39-571) ng/mL to 107 (27-426) ng/mL. Upfront treatment with doublet therapy in these men simultaneously increased from 1% (7 of 991) in 2016 to 44% (402 of 922) in 2020. The adjusted 5-year overall survival increased from 26% (95% CI, 25%-28%) from 2008 to 2012 to 35% (95% CI, 31%-40%) from 2017 to 2020. During the first 5 years after diagnosis, there was an increase in mean survival of 6 months, from 2.7 (95% CI, 2.6-2.8) years from 2008 to 2012 to 3.2 (95% CI, 3.1-3.1) years from 2017 to 2020.

Conclusions and Relevance

In parallel with improvements in treatment of advanced prostate cancer, a clinically meaningful increase in mean survival was observed in men with de novo mCSPC in Sweden between 2008 and 2020 in this study.

Sustained release of alpha-methylacyl-CoA racemase (AMACR) antibody-conjugated and free doxorubicin from silica nanoparticles for prostate cancer cell growth inhibition

This article presents silica nanoparticles for the sustained release of AMACR antibody-conjugated and free doxorubicin (DOX) for the inhibition of prostate cancer cell growth. Inorganic MCM-41 silica nanoparticles were synthesized, functionalized with phenylboronic acid groups (MCM-B), and capped with dextran (MCM-B-D). The nanoparticles were then characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, zeta potential analysis, nitrogen sorption, X-ray diffraction, and thermogravimetric analysis, before exploring their potential for drug loading and controlled drug release. This was done using a model prostate cancer drug, DOX, and a targeted prostate cancer drug, α-Methyl Acyl-CoA racemase (AMACR) antibody-conjugated DOX, which attaches specifically to AMACR proteins that are overexpressed on the surfaces of prostate cancer cells. The kinetics of sustained drug release over 30 days was then studied using zeroth order, first order, second order, Higuchi, and the Korsmeyer-Peppas models, while the thermodynamics of drug release was elucidated by determining the entropy and enthalpy changes. The flux of the released DOX was also simulated using the COMSOL Multiphysics software package. Generally, the AMACR antibody-conjugated DOX drug-loaded nanoparticles were more effective than the free DOX drug-loaded formulations in inhibiting the growth of prostate cancer cells in vitro over a 96 h period. The implications of the results are then discussed for the development of drug-eluting structures for the localized and targeted treatment of prostate cancer.

Anti-PSMA monoclonal antibody increases the toxicity of paclitaxel carried by carbon nanotubes

Multiple-wall carbon nanotubes (CNTs) were functionalized with polyethyleneimine in order to incorporate paclitaxel (PTX), the first line chemotherapeutic agent for prostate cancer. These particles were then covered with antibodies for the prostate-specific membrane antigen (PSMA), to address them to prostate cancer cells. LNCaP prostate cancer cells (PSMA⁺), HCT-116 and CaCo-2 colon cancer cells (PSMA^-), as well as human peripheral monocytes and lymphocytes (PSMA^-), were in vitro exposed to fluorescent CNT composites. The interaction/adherence of those composites to target cells was analyzed by fluorescence microscopy and flow cytometry, showing a diffuse interaction of CNTs and CNT-PTX with all cell types. Analysis of cytotoxicity revealed that both prostate (PSMA⁺) and colorectal cancer cells (PSMA^-) were more susceptible to PTX complexed with CNTs than to pure PTX or CNTs alone, while the incorporation of anti-PSMA (CNT-PTX-PSMA) improved the toxicity on LNCaP cells but not on PSMA^- targets. No toxicity was observed in human monocytes and lymphocytes but composites induced phenotypical changes in monocytes. Our results demonstrate the feasibility of using anti-PSMA antibody to address drug-loaded CNT to cancer cells as a strategy for improving the effectiveness of antineoplastic agents.

Novel treatment options in the management of metastatic castration-naïve prostate cancer; which treatment modality to choose?

Androgen-deprivation therapy (ADT) has been the mainstay of treatment of metastatic prostate cancer since the first report of its hormonal dependence in the 1940s. Since 2015, the addition of docetaxel and the addition of abiraterone to ADT have conferred substantial overall survival benefit in men with metastatic castration-naïve prostate cancer (mCNPC). The shift of these treatment options for metastatic prostate cancer from the castration-resistant setting to the castration-naïve setting has led to new challenges in the management of this disease. It remains to be determined which patients may benefit most from either early concomitant docetaxel or from abiraterone with ADT, since biomarkers for early therapy response and risk stratification are currently lacking. Therefore, the ability to personalize medicine is hampered. Furthermore, the earlier detection of metastatic prostate cancer by using new imaging modalities makes the application of clinical trial results in daily practice increasingly challenging. Recently, both local radiotherapy to the primary tumor combined with ADT and abiraterone combined with ADT showed a survival benefit in low-volume disease patients. The latest data also demonstrated a survival benefit with the addition of apalutamide or enzalutamide to ADT. The extent of metastatic disease may become one of the most important factors to determine treatment choice. In this review article, we summarize trial data to provide guidance for treatment selection in metastatic castration-naïve prostate cancer.

Chelerythrine induced cell death through ROS-dependent ER stress in human prostate cancer cells

INTRODUCTION

Prostate cancer is the most common noncutaneous cancer and the second leading cause of cancer-related mortality worldwide and the third in USA in 2017. Chelerythrine (CHE), a naturalbenzo[c]phenanthridine alkaloid, formerly identified as a protein kinase C inhibitor, has also shown anticancer effect through a number of mechanisms. Herein, effect and mechanism of the CHE-induced apoptosis via reactive oxygen species (ROS)-mediated endoplasmic reticulum (ER) stress in prostate cancer cells were studied for the first time.

METHODS

In our present study, we investigated whether CHE induced cell viability decrease, colony formation inhibition, and apoptosis in a dose-dependent manner in PC-3 cells. In addition, we showed that CHE increases intracellular ROS and leads to ROS-dependent ER stress and cell apoptosis.

RESULTS

Pre-treatment with N-acetyl cysteine, an ROS scavenger, totally reversed the CHE-induced cancer cell apoptosis as well as ER stress activation, suggesting that the ROS generation was responsible for the anticancer effects of CHE.

CONCLUSION

Taken together, our findings support one of the anticancer mechanisms by which CHE increased ROS accumulation in prostate cancer cells, thereby leading to ER stress and caused intrinsic apoptotic signaling. The study reveals that CHE could be a potential candidate for application in the treatment of prostate cancer.

Seven-month prostate-specific antigen (PSA) is prognostic in patients with prostate cancer initially diagnosed with distant metastases

Recent research suggests that prostate-specific antigen (PSA) ≤ 0.2 ng/dl at 7 months is prognostic for better survival with androgen deprivation therapy for metastatic hormone-sensitive prostate cancer regardless of chemotherapy with docetaxel. These results were derived from a group of clinical trial participants. Therefore, we performed a confirmatory analysis in patients treated outside of trials. Furthermore, we limited inclusion to those who presented with metastases at the initial diagnosis of prostate cancer (synchronous metastases). A retrospective analysis of a comprehensive regional database was performed. The oncology care in this region (Nordland County, Northern Norway) was provided by one center. Patients who were diagnosed between January 01, 2004 and December 31, 2016 were included. Of 101 patients, 90 were alive at 7 months and had their PSA value measured. Their median age was 68.5 years. Only six patients (7%) achieved PSA ≤ 0.2 ng/dl at 7 months. The median value was 4.05 ng/dl. Median overall survival was shortest in patients with PSA > 4.0 ng/dl (22 months). For patients with PSA between 0.3 and 4.0 ng/dl, median survival was 54 months (p = 0.0001). No further increase was seen in the small group with lower PSA. Statistical significance was also found for a cutoff of ≤ 1.0 ng/dl (55 vs. 32 months). PSA at 7 months predicts overall survival. Given that only 7% of patients achieved PSA ≤ 0.2 ng/dl, confirmation of this particular cutoff requires additional studies in other populations.

Burden of Metastatic Castrate Naive Prostate Cancer Patients, to Identify Men More Likely to Benefit from Early Docetaxel: Further Analyses of CHAARTED and GETUG-AFU15 Studies

BACKGROUND

Docetaxel (D) at the time of starting androgen deprivation therapy (ADT) for metastatic castrate naive prostate cancer shows a clear survival benefit for patients with high-volume (HV) disease. It is unclear whether patients with low-volume (LV) disease benefit from early D.

OBJECTIVE

To define the overall survival (OS) of aggregate data of patient subgroups from the CHAARTED and GETUG-AFU15 studies, defined by metastatic burden (HV and LV) and time of metastasis occurrence (at diagnosis or after prior local treatment [PRLT]).

DESIGN, SETTING, AND PARTICIPANTS

Data were accessed from two independent phase III trials of ADT alone or ADT+D-GETUG-AFU15 (N=385) and CHAARTED (N=790), with median follow-ups for survivors of 83.2 and 48.2 mo, respectively. The definition of HV and LV disease was harmonized.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary end point was OS.

RESULTS AND LIMITATIONS

Meta-analysis results of the aggregate data showed significant heterogeneity in ADT+D versus ADT effect sizes between HV and LV subgroups (p=0.017), and failed to detect heterogeneity in ADT+D versus ADT effect sizes between upfront and PRLT subgroups (p=0.4). Adding D in patients with HV disease has a consistent effect in improving median OS (HV-ADT: 34.4 and 35.1 mo, HV-ADT+D: 51.2 and 39.8 mo in CHAARTED and GETUG-AFU15, respectively; pooled average hazard ratio or HR (95% confidence interval [CI]) 0.68 ([95% CI 0.56; 0.82], p<0.001). Patients with LV disease showed much longer OS, without evidence that D improved OS (LV-ADT: not reached [NR] and 83.4; LV-ADT+D: 63.5 and NR in CHAARTED and GETUG-AFU15, respectively; pooled HR (95% CI) 1.03 (95% CI 0.77; 1.38). Aggregate data showed no evidence of heterogeneity of early D in LV and HV subgroups irrespective of whether patients had PRLT or not. Post hoc subgroup analysis was based on aggregated data from two independent phase III randomized trials.

CONCLUSIONS

There was no apparent survival benefit in the CHAARTED and GETUG-AFU15 studies with D for LV. Across both studies, early D showed consistent effect and improved OS in HV patients.

PATIENT SUMMARY

Patients with a higher burden of metastatic prostate cancer starting androgen deprivation therapy (ADT) have a poorer prognosis and are more likely to benefit from early docetaxel. Low-volume patients have longer overall survival with ADT alone, and the toxicity of docetaxel may outweigh its benefits.

Treatment with docetaxel in combination with Aneustat leads to potent inhibition of metastasis in a patient-derived xenograft model of advanced prostate cancer

Background:

Docetaxel used for first-line treatment of advanced prostate cancer (PCa) is only marginally effective. We previously showed, using the LTL-313H subrenal capsule patient-derived metastatic PCa xenograft model, that docetaxel combined with Aneustat (OMN54), a multivalent plant-derived therapeutic, led to marked synergistic tumour growth inhibition. Here, we investigated the effect of docetaxel+Aneustat on metastasis.

Methods:

C4-2 cells were incubated with docetaxel, Aneustat and docetaxel+Aneustat to assess effects on cell migration. The LTL-313H model, similarly treated, was analysed for effects on lung micro-metastasis and kidney invasion. The LTL-313H gene expression profile was compared with profiles of PCa patients (obtained from Oncomine) and subjected to IPA to determine involvement of cancer driver genes.

Results:

Docetaxel+Aneustat markedly inhibited C4-2 cell migration and LTL-313H lung micro-metastasis/kidney invasion. Oncomine analysis indicated that treatment with docetaxel+Aneustat was associated with improved patient outcome. The drug combination markedly downregulated expression of cancer driver genes such as FOXM1 (and FOXM1-target genes). FOXM1 overexpression reduced the anti-metastatic activity of docetaxel+Aneustat.

Conclusions:

Docetaxel+Aneustat can inhibit PCa tissue invasion and metastasis. This activity appears to be based on reduced expression of cancer driver genes such as FOXM1. Use of docetaxel+Aneustat may provide a new, more effective regimen for therapy of metastatic PCa.

Treatment effects in prostate cancer

Nonsurgical treatments for prostate cancer include androgen-deprivation therapy (ADT), radiation therapy (RT), ablative therapies, chemotherapy, and newly emerging immunotherapies. These approaches can be used alone or in combination depending on the clinical scenario. ADT is typically reserved for high-risk locally or systemically advanced disease that is not amenable to curative surgery. Radiation therapy can be used instead of surgery as primary therapy with curative intent for low-intermediate-risk disease as well as for control of locally advanced disease not suitable for surgery. Ablative therapies can be used as primary therapy for low-intermediate-risk disease or as salvage therapy for clinically localized disease where RT has failed. Chemotherapy and immune-based therapies are currently used for androgen-independent disease, although the indications for these approaches may well change as new data from clinical trials accrue. Pathologists should be able to recognize tissue changes associated with these treatments to provide information that will optimize patient management. This is particularly true in situations where clinical history of recent or remote nonsurgical treatment is not provided with the specimen. In the absence of this information, pathologists encountering the features described herein are encouraged to review patient records or communicate directly with clinical colleagues to determine how a given patient was treated and when.