Urinary extracellular vesicle-derived miR-126-3p predicts lymph node invasion in patients with high-risk prostate cancer.

To investigate extracellular vesicles (EVs), biomarkers for predicting lymph node invasion (LNI) in patients with high-risk prostate cancer (HRPCa), plasma, and/or urine samples were prospectively collected from 45 patients with prostate cancer (PCa) and five with benign prostatic hyperplasia (BPH). Small RNA sequencing was performed to identify miRNAs in the EVs. All patients with PCa underwent radical prostatectomy and extended pelvic lymph node dissection. Differentially expressed miRNAs were identified in patients with and without pathologically-verified LNI. The candidate miRNAs were validated in low-risk prostate cancer (LRPCa) and BPH. Four miRNA species (e.g., miR-126-3p) and three miRNA species (e.g., miR-27a-3p) were more abundant in urinary and plasma EVs, respectively, of patients with PCa. None of these miRNA species were shared between urinary and plasma EVs. miR-126-3p was significantly more abundant in patients with HR PCa with LNI than in those without (P = 0.018). miR-126-3p was significantly more abundant in the urinary EVs of patients with HRPCa than in those with LRPCa (P = 0.017) and BPH (P = 0.011). In conclusion, urinary EVs-derived miR-126-3p may serve as a good biomarker for predicting LNI in patients with HRPCa.

Dysregulated Ribosome Biogenesis Is a Targetable Vulnerability in Triple-Negative Breast Cancer: MRPS27 as a Key Mediator of the Stemness-inhibitory Effect of Lovastatin.

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with limited effective therapeutic options readily available. We have previously demonstrated that lovastatin, an FDA-approved lipid-lowering drug, selectively inhibits the stemness properties of TNBC. However, the intracellular targets of lovastatin in TNBC remain largely unknown. Here, we unexpectedly uncovered ribosome biogenesis as the predominant pathway targeted by lovastatin in TNBC. Lovastatin induced the translocation of ribosome biogenesis-related proteins including nucleophosmin (NPM), nucleolar and coiled-body phosphoprotein 1 (NOLC1), and the ribosomal protein RPL3. Lovastatin also suppressed the transcript levels of rRNAs and increased the nuclear protein level and transcriptional activity of p53, a master mediator of nucleolar stress. A prognostic model generated from 10 ribosome biogenesis-related genes showed outstanding performance in predicting the survival of TNBC patients. Mitochondrial ribosomal protein S27 (MRPS27), the top-ranked risky model gene, was highly expressed and correlated with tumor stage and lymph node involvement in TNBC. Mechanistically, MRPS27 knockdown inhibited the stemness properties and the malignant phenotypes of TNBC. Overexpression of MRPS27 attenuated the stemness-inhibitory effect of lovastatin in TNBC cells. Our findings reveal that dysregulated ribosome biogenesis is a targetable vulnerability and targeting MRPS27 could be a novel therapeutic strategy for TNBC patients.

Urinary extracellular vesicle-derived miR-126-3p predicts lymph node invasion in patients with high-risk prostate cancer.

To investigate extracellular vesicles (EVs) biomarkers for predicting lymph node invasion (LNI) in patients with high-risk prostate cancer (HRPCa), plasma and/or urine samples were prospectively collected from 45 patients with prostate cancer (PCa) and five with benign prostatic hyperplasia (BPH). Small RNA sequencing was performed to identify miRNAs in the EVs. All patients with PCa underwent radical prostatectomy and extended pelvic lymph node dissection. Differentially-expressed miRNAs were identified in patients with and without pathologically-verified LNI. The candidate miRNAs were validated in low-risk prostate cancer (LRPCa) and BPH. Four miRNA species (e.g. miR-126-3p) and three miRNA species (e.g. miR-27a-3p) were more abundant in urinary and plasma EVs, respectively, of patients with PCa. None of these miRNA species were shared between urinary and plasma EVs. miR-126-3p was significantly more abundant in patients with HR PCa with LNI than in those without (P = 0.018). miR-126-3p was significantly more abundant in the urinary EVs of patients with HRPCa than in those with LRPCa (P = 0.017) and BPH (P = 0.011). In conclusion, urinary EVs-derived miR-126-3p may serve as a good biomarker for predicting LNI in patients with HRPCa.

A CXCR4 inhibitor (balixafortide) enhances docetaxel-mediated antitumor activity in a murine model of prostate cancer bone metastasis.

BACKGROUND: Prostate cancer (PCa) bone metastases have been shown to be more resistant to docetaxel than soft tissue metastases. The proinflammatory chemokine receptor CXCR4 has been shown to confer resistance to docetaxel (DOC) in PCa cells. Balixafortide (BLX) is a protein epitope mimetic inhibitor of CXCR4. Accordingly, we hypothesized that BLX would enhance DOC-mediated antitumor activity in PCa bone metastases. METHODS: PC-3 luciferase-labeled cells were injected into the tibia of mice to model bone metastases. Four treatment groups were created: vehicle, DOC (5 mg/kg), BLX (20 mg/kg), and combo (receiving both DOC and BLX). Mice were injected twice daily subcutaneously with either vehicle or BLX starting on Day 1 and weekly intraperitoneally with DOC starting on Day 1. Tumor burden was measured weekly via bioluminescent imaging. At end of study (29 days), radiographs were taken of the tibiae and blood was collected. Serum levels of TRAcP, IL-2, and IFNγ levels were measured using ELISA. Harvested tibiae were decalcified and stained for Ki67, cleaved caspase-3, and CD34 positive cells or microvessels were quantified. RESULTS: Tumor burden was lower in the combo group compared to the DOC alone group. Treatment with the combination had no impact on the number of mice with osteolytic lesions, however the area of osteolytic lesions was lower in the combo group compared to the vehicle and BLX groups, but not the DOC group. Serum TRAcP levels were lower in the combo compared to vehicle group, but not the other groups. No significant difference in Ki67 staining was found among the groups; whereas, cleaved caspase-3 staining was lowest in the Combo group and highest in the BLX group. The DOC and combo groups had more CD34+ microvessels than the control and BLX groups. There was no difference between the treatment groups for IL-2, but the combo group had increased levels of IFNγ compared to the DOC group. CONCLUSIONS: Our data demonstrate that a combination of BAL and DOC has greater antitumor activity in a model of PCa bone metastases than either drug alone. These data support further evaluation of this combination in metastatic PCa.

Integration of Single-Cell RNA-Sequencing and Network Analysis to Investigate Mechanisms of Drug Resistance.

Innate resistance and therapeutic-driven development of resistance to anticancer drugs is a common complication of cancer therapy. Understanding mechanisms of drug resistance can lead to development of alternative therapies. One strategy is to subject drug-sensitive and drug-resistant variants to single-cell RNA-seq (scRNA-seq) and to subject the scRNA-seq data to network analysis to identify pathways associated with drug resistance. This protocol describes a computational analysis pipeline to study drug resistance by subjecting scRNA-seq expression data to Passing Attributes between Networks for Data Assimilation (PANDA), an integrative network analysis tool that incorporates protein-protein interactions (PPI) and transcription factor (TF)-binding motifs.

The Role of Tumor Epithelial-Mesenchymal Transition and Macrophage Crosstalk in Cancer Progression.

PURPOSE OF REVIEW: The purpose of this review is to summarize the recently published findings regarding the role of epithelial to mesenchymal transition (EMT) in tumor progression, macrophages in the tumor microenvironment, and crosstalk that exists between tumor cells and macrophages. RECENT FINDINGS: EMT is a crucial process in tumor progression. In association with EMT changes, macrophage infiltration of tumors occurs frequently. A large body of evidence demonstrates that various mechanisms of crosstalk exist between macrophages and tumor cells that have undergone EMT resulting in a vicious cycle that promotes tumor invasion and metastasis. Tumor-associated macrophages and tumor cells undergoing EMT provide reciprocal crosstalk which leads to tumor progression. These interactions provide potential targets to exploit for therapy.

Bone Marrow Macrophages Induce Inflammation by Efferocytosis of Apoptotic Prostate Cancer Cells via HIF-1α Stabilization.

The clearance of apoptotic cancer cells by macrophages, known as efferocytosis, fuels the bone-metastatic growth of prostate cancer cells via pro-inflammatory and immunosuppressive processes. However, the exact molecular mechanisms remain unclear. In this study, single-cell transcriptomics of bone marrow (BM) macrophages undergoing efferocytosis of apoptotic prostate cancer cells revealed a significant enrichment in their cellular response to hypoxia. Here, we show that BM macrophage efferocytosis increased hypoxia inducible factor-1alpha (HIF-1α) and STAT3 phosphorylation (p-STAT3 at Tyr705) under normoxic conditions, while inhibitors of p-STAT3 reduced HIF-1α. Efferocytosis promoted HIF-1α stabilization, reduced its ubiquitination, and induced HIF-1α and p-STAT3 nuclear translocation. HIF-1α stabilization in efferocytic BM macrophages resulted in enhanced expression of pro-inflammatory cytokine MIF, whereas BM macrophages with inactive HIF-1α reduced MIF expression upon efferocytosis. Stabilization of HIF-1α using the HIF-prolyl-hydroxylase inhibitor, Roxadustat, enhanced MIF expression in BM macrophages. Furthermore, BM macrophages treated with recombinant MIF protein activated NF-κB (p65) signaling and increased the expression of pro-inflammatory cytokines. Altogether, these findings suggest that the clearance of apoptotic cancer cells by BM macrophages triggers p-STAT3/HIF-1α/MIF signaling to promote further inflammation in the bone tumor microenvironment where a significant number of apoptotic cancer cells are present.

Integrated Workflow for the Label-Free Isolation and Genomic Analysis of Single Circulating Tumor Cells in Pancreatic Cancer.

As pancreatic cancer is the third deadliest cancer in the U.S., the ability to study genetic alterations is necessary to provide further insight into potentially targetable regions for cancer treatment. Circulating tumor cells (CTCs) represent an especially aggressive subset of cancer cells, capable of causing metastasis and progressing the disease. Here, we present the Labyrinth-DEPArray pipeline for the isolation and analysis of single CTCs. Established cell lines, patient-derived CTC cell lines and freshly isolated CTCs were recovered and sequenced to reveal single-cell copy number variations (CNVs). The resulting CNV profiles of established cell lines showed concordance with previously reported data and highlight several gains and losses of cancer-related genes such as FGFR3 and GNAS. The novel sequencing of patient-derived CTC cell lines showed gains in chromosome 8q, 10q and 17q across both CTC cell lines. The pipeline was used to process and isolate single cells from a metastatic pancreatic cancer patient revealing a gain of chromosome 1q and a loss of chromosome 5q. Overall, the Labyrinth-DEPArray pipeline offers a validated workflow combining the benefits of antigen-free CTC isolation with single cell genomic analysis.

Differential immune landscapes in appendicular versus axial skeleton.

Roughly 400,000 people in the U.S. are living with bone metastases, the vast majority occurring in the spine. Metastases to the spine result in fractures, pain, paralysis, and significant health care costs. This predilection for cancer to metastasize to the bone is seen across most cancer histologies, with the greatest incidence seen in prostate, breast, and lung cancer. The molecular process involved in this predilection for axial versus appendicular skeleton is not fully understood, although it is likely that a combination of tumor and local micro-environmental factors plays a role. Immune cells are an important constituent of the bone marrow microenvironment and many of these cells have been shown to play a significant role in tumor growth and progression in soft tissue and bone disease. With this in mind, we sought to examine the differences in immune landscape between axial and appendicular bones in the normal noncancerous setting in order to obtain an understanding of these landscapes. To accomplish this, we utilized mass cytometry by time-of-flight (CyTOF) to examine differences in the immune cell landscapes between the long bone and vertebral body bone marrow from patient clinical samples and C57BL/6J mice. We demonstrate significant differences between immune populations in both murine and human marrow with a predominance of myeloid progenitor cells in the spine. Additionally, cytokine analysis revealed differences in concentrations favoring a more myeloid enriched population of cells in the vertebral body bone marrow. These differences could have clinical implications with respect to the distribution and permissive growth of bone metastases.

A Bioreactor for 3D In Vitro Modeling of the Mechanical Stimulation of Osteocytes.

The bone is a mechanosensitive organ that is also a common metastatic site for prostate cancer. However, the mechanism by which the tumor interacts with the bone microenvironment to further promote disease progression remains to be fully understood. This is largely due to a lack of physiological yet user-friendly models that limit our ability to perform in-depth mechanistic studies. Here, we report a tunable bioreactor which facilitates the 3D culture of the osteocyte cell line, MLO-Y4, in a hydroxyapatite/tricalcium phosphate (HA/TCP) scaffold under constant fluidic shear stress and tunable hydrostatic pressure within physiological parameters. Increasing hydrostatic pressure was sufficient to induce a change in the expression of several bone remodeling genes such as Dmp1, Rankl, and Runx2. Furthermore, increased hydrostatic pressure induced the osteocytes to promote the differentiation of the murine macrophage cell line RAW264.7 toward osteoclast-like cells. These results demonstrate that the bioreactor recapitulates the mechanotransduction response of osteocytes to pressure including the measurement of their functional ability in a 3D environment. In conclusion, the bioreactor would be useful for exploring the mechanisms of osteocytes in bone health and disease.

Pheno-SELEX: Engineering Anti-Metastatic Aptamers through Targeting the Invasive Phenotype Using Systemic Evolution of Ligands by Exponential Enrichment.

Multiple methods (e.g., small molecules and antibodies) have been engineered to target specific proteins and signaling pathways in cancer. However, many mediators of the cancer phenotype are unknown and the ability to target these phenotypes would help mitigate cancer. Aptamers are small DNA or RNA molecules that are designed for therapeutic use. The design of aptamers to target cancers can be challenging. Accordingly, to engineer functionally anti-metastatic aptamers we used a modification of systemic evolution of ligands by exponential enrichment (SELEX) we call Pheno-SELEX to target a known phenotype of cancer metastasis, i.e., invasion. A highly invasive prostate cancer (PCa) cell line was established and used to identify aptamers that bound to it with high affinity as opposed to a less invasive variant to the cell line. The anti-invasive aptamer (AIA1) was found to inhibit in vitro invasion of the original highly invasive PCa cell line, as well as an additional PCa cell line and an osteosarcoma cell line. AIA1 also inhibited in vivo development of metastasis in both a PCa and osteosarcoma model of metastasis. These results indicate that Pheno-SELEX can be successfully used to identify aptamers without knowledge of underlying molecular targets. This study establishes a new paradigm for the identification of functional aptamers.

Transcription factor network analysis based on single cell RNA-seq identifies that Trichostatin-a reverses docetaxel resistance in prostate Cancer.

BACKGROUND: Overcoming drug resistance is critical for increasing the survival rate of prostate cancer (PCa). Docetaxel is the first cytotoxic chemotherapeutical approved for treatment of PCa. However, 99% of PCa patients will develop resistance to docetaxel within 3 years. Understanding how resistance arises is important to increasing PCa survival. METHODS: In this study, we modeled docetaxel resistance using two PCa cell lines: DU145 and PC3. Using the Passing Attributes between Networks for Data Assimilation (PANDA) method to model transcription factor (TF) activity networks in both sensitive and resistant variants of the two cell lines. We identified edges and nodes shared by both PCa cell lines that composed a shared TF network that modeled changes which occur during acquisition of docetaxel resistance in PCa. We subjected the shared TF network to connectivity map analysis (CMAP) to identify potential drugs that could disrupt the resistant networks. We validated the candidate drug in combination with docetaxel to treat docetaxel-resistant PCa in both in vitro and in vivo models. RESULTS: In the final shared TF network, 10 TF nodes were identified as the main nodes for the development of docetaxel resistance. CMAP analysis of the shared TF network identified trichostatin A (TSA) as a candidate adjuvant to reverse docetaxel resistance. In cell lines, the addition of TSA to docetaxel enhanced cytotoxicity of docetaxel resistant PCa cells with an associated reduction of the IC50 of docetaxel on the resistant cells. In the PCa mouse model, combination of TSA and docetaxel reduced tumor growth and final weight greater than either drug alone or vehicle. CONCLUSIONS: We identified a shared TF activity network that drives docetaxel resistance in PCa. We also demonstrated a novel combination therapy to overcome this resistance. This study highlights the usage of novel application of single cell RNA-sequencing and subsequent network analyses that can reveal novel insights which have the potential to improve clinical outcomes.

Effects of Analgesics on Tumor Growth in Mouse Models of Prostate Cancer Bone Metastasis.

Murine models of tumor development often require invasive procedures for tumor implantation, potentially causing pain or distress. However, analgesics are often withheld during implantation because of concerns that they may adversely affect tumor development. Previous studies examining the effects of analgesics on the development and metastasis of various tumor lines show that the effect of analgesics depends on the tumor line and analgesic used. A blanket statement that analgesics affect the general growth of tumors is not adequate scientific justification for withholding pain relief, and pilot studies or references are recommended for each specific tumor cell line and treatment combination. In this study, we evaluated the effects of 2 commonly used analgesics on tumor growth in 2 models of prostate cancer (PCa) bone metastasis. We hypothesized that a one-time injection of analgesics at the time of intratibial injection of tumor cells would not significantly impact tumor growth. Either C57BL/6 or SCID mice were injected subcutaneously with an analgesic (carprofen [5 mg/kg], or buprenorphine [0.1 mg/kg]) or vehicle (0.1 mL of saline) at the time of intratibial injection with a PCa cell line (RM1 or PC3, n = 10 to 11 per group). Tumor growth (measured by determination of tumor burden and the extent of bone involvement) and welfare (measured by nociception, locomotion, and weight) were monitored for 2 to 4 wk. Neither carprofen or buprenorphine administration consistently affected tumor growth or indices of animal welfare as compared with the saline control for either cell line. This study adds to the growing body of literature demonstrating that analgesia can be compatible with scientific objectives, and that a decision to withhold analgesics must be scientifically justified and evaluated on a model-specific basis.

Cigarette smoke-associated inflammation impairs bone remodeling through NFκB activation.

BACKGROUND: Cigarette smoking constitutes a major lifestyle risk factor for osteoporosis and hip fracture. It is reported to impair the outcome of many clinical procedures, such as wound infection treatment and fracture healing. Importantly, although several studies have already demonstrated the negative correlation between cigarette consume and impaired bone homeostasis, there is still a poor understanding of how does smoking affect bone health, due to the lack of an adequately designed animal model. Our goal was to determine that cigarette smoke exposure impairs the dynamic bone remodeling process through induction of bone resorption and inhibition of bone formation. METHODS: We developed cigarette smoke exposure protocols exposing mice to environmental smoking for 10 days or 3 months to determine acute and chronic smoke exposure effects. We used these models, to demonstrate the effect of smoking exposure on the cellular and molecular changes of bone remodeling and correlate these early alterations with subsequent bone structure changes measured by microCT and pQCT. We examined the bone phenotype alterations in vivo and ex vivo in the acute and chronic smoke exposure mice by measuring bone mineral density and bone histomorphometry. Further, we measured osteoclast and osteoblast differentiation gene expression levels in each group. The function changes of osteoclast or osteoblast were evaluated. RESULTS: Smoke exposure caused a significant imbalance between bone resorption and bone formation. A 10-day exposure to cigarette smoke sufficiently and effectively induced osteoclast activity, leading to the inhibition of osteoblast differentiation, although it did not immediately alter bone structure as demonstrated in mice exposed to smoke for 3 months. Cigarette smoke exposure also induced DNA-binding activity of nuclear factor kappaB (NFκB) in osteoclasts, which subsequently gave rise to changes in bone remodeling-related gene expression. CONCLUSIONS: Our findings suggest that smoke exposure induces RANKL activation-mediated by NFκB, which could be a "smoke sensor" for bone remodeling.

Extracellular Vesicles and Bone-Associated Cancer.

PURPOSE OF REVIEW: In this review, we describe the biology of extracellular vesicles (EV) and how they contribute to bone-associated cancers. RECENT FINDINGS: Crosstalk between tumor and bone has been demonstrated to promote tumor and metastatic progression. In addition to direct cell-to-cell contact and soluble factors, such as cytokines, EVs mediate crosstalk between tumor and bone. EVs are composed of a heterogenous group of membrane-delineated vesicles of varying size range, mechanisms of formation, and content. These include apoptotic bodies, microvesicles, large oncosomes, and exosomes. EVs derived from primary tumors have been shown to alter bone remodeling and create formation of a pre-metastatic niche that favors development of bone metastasis. Similarly, EVs from marrow stromal cells have been shown to promote tumor progression. Additionally, EVs can act as therapeutic delivery vehicles due to their low immunogenicity and targeting specificity. EVs play critical roles in intercellular communication. Multiple classes of EVs exist based on size on mechanism of formation. In addition to a role in pathophysiology, EVs can be exploited as therapeutic delivery vehicles.

'Educated' Osteoblasts Reduce Osteoclastogenesis in a Bone-Tumor Mimetic Microenvironment.

Breast cancer (BC) metastases to bone disrupt the balance between osteoblasts and osteoclasts, leading to excessive bone resorption. We identified a novel subpopulation of osteoblasts with tumor-inhibitory properties, called educated osteoblasts (EOs). Here we sought to examine the effect of EOs on osteoclastogenesis during tumor progression. We hypothesized that EOs affect osteoclast development in the bone-tumor niche, leading to suppressed pre-osteoclast fusion and bone resorption. Conditioned media (CM) was analyzed for protein expression of osteoclast factors receptor activator of nuclear factor kappa-ß ligand (RANKL), osteoprotegerin (OPG), and tumor necrosis factor alpha (TNFα) via ELISA. EOs were co-cultured with pre-osteoclasts on a bone mimetic matrix to assess osteoclast resorption. Pre-osteoclasts were tri-cultured with EOs plus metastatic BC cells and assessed for tartrate-resistance acid phosphatase (TRAP)-positive, multinucleated (≥3 nuclei), mature osteoclasts. Tumor-bearing murine tibias were stained for TRAP to determine osteoclast number in-vivo. EO CM expressed reduced amounts of soluble TNFα and OPG compared to naïve osteoblast CM. Osteoclasts formed in the presence of EOs were smaller and less in number. Upon co-culture on a mimetic bone matrix, a 50% reduction in the number of TRAP-positive osteoclasts formed in the presence of EOs was observed. The tibia of mice inoculated with BC cells had less osteoclasts per bone surface in bones with increased numbers of EO cells. These data suggest EOs reduce osteoclastogenesis and bone resorption. The data imply EOs provide a protective effect against bone resorption in bone metastatic BC.

Photoacoustic spectral analysis at ultraviolet wavelengths for characterizing the Gleason grades of prostate cancer.

The diagnosis of aggressive prostate cancer (PCa) has relied on microscopic architectures, namely Gleason patterns, of tissues extracted through core biopsies. Technology capable of assessing the tissue architecture without tissue extraction will reduce the invasiveness of PCa diagnosis and improve diagnostic accuracy by allowing for more sampling locations. Our recently developed photoacoustic spectral analysis (PASA) has achieved quantification of tissue architectural heterogeneity interstitially. Taking advantage of the unique optical absorption of cell nuclei at ultraviolet (UV) wavelengths, this study investigated PASA at 266 nm for quantifying the tissue architecture heterogeneity in prostates. The results have shown significant differences among the normal, early cancer, and late cancer stages in mouse prostates ex vivo and in vivo (n=20, p<0.05). The study with human samples ex vivo has shown a correlation of 0.80 (n=11, p<0.05) between PASA quantification and pathologic diagnosis.

Curcumin Nanoparticles and Their Cytotoxicity in Docetaxel-Resistant Castration-Resistant Prostate Cancer Cells.

Most prostate cancer patients develop resistance to anti-androgen therapy. This is referred to as castration-resistant prostate cancer (CRPC). Docetaxel (DTX) is the mainstay treatment against CRPC. However, over time patients eventually develop DTX resistance, which is the cause of the cancer-related mortality. Curcumin (CUR) as a natural compound has been shown to have very broad pharmacological activities, e.g., anti-inflammatory and antioxidant properties. However, CUR is very hydrophobic. The objective of this study was to develop CUR nanoparticles (NPs) and evaluate their cytotoxicity in DTX-resistant CRPC cells for the treatment of DTX-resistant CRPC. We tested solubility of CUR in different lipids and surfactants. Finally, Miglyol 812 and D-alpha-tocopheryl poly (ethylene glycol) succinate 1000 (TPGS) were chosen to prepare lipid-based NPs for CUR. We fully characterized CUR NPs that had particle size < 150 nm, high drug loading (7.5%), and entrapment efficiency (90%). Moreover, the CUR NPs were successfully lyophilized without using cryoprotectants. We tested the cytotoxicity of blank NPs, free CUR, and CUR NPs in sensitive DU145 and PC3 cells as well as their matching docetaxel-resistant cells. Cytotoxicity studies showed that blank NPs were very safe for all tested prostate cancer cell lines. Free CUR overcame the resistance in PC3 cells, but not in DU145 cells. In contrast, CUR NPs significantly increased CUR potency in all tested cell lines. Importantly, CUR NPs completely restored CUR potency in both resistant DU145 and PC3 cells. These results demonstrate that the CUR NPs have potential to overcome DTX resistance in CRPC.