Heterogeneous Prostate Research Articles

Preparation, Optimization, and In-Vitro Evaluation of Brusatol- and Docetaxel-Loaded Nanoparticles for the Treatment of Prostate Cancer.

Challenges to docetaxel use in prostate cancer treatment include several resistance mechanisms as well as toxicity. To overcome these challenges and to improve the therapeutic efficacy in heterogeneous prostate cancer, the use of multiple agents that can destroy different subpopulations of the tumor is required. Brusatol, a multitarget inhibitor, has been shown to exhibit potent anticancer activity and play an important role in drug response and chemoresistance. Thus, the combination of brusatol and docetaxel in a nanoparticle platform for the treatment of prostate cancer is expected to produce synergistic effects. In this study, we reported the development of polymeric nanoparticles for the delivery of brusatol and docetaxel in the treatment of prostate cancer. The one-factor-at-a-time method was used to screen for formulation and process variables that impacted particle size. Subsequently, factors that had modifiable effects on particle size were evaluated using a 24 full factorial statistical experimental design followed by the optimization of drug loading. The optimization of blank nanoparticles gave a formulation with a mean size of 169.1 nm ± 4.8 nm, in agreement with the predicted size of 168.333 nm. Transmission electron microscopy showed smooth spherical nanoparticles. The drug release profile showed that the encapsulated drugs were released over 24 h. Combination index data showed a synergistic interaction between the drugs. Cell cycle analysis and the evaluation of caspase activity showed differences in PC-3 and LNCaP prostate cancer cell responses to the agents. Additionally, immunoblots showed differences in survivin expression in LNCaP cells after treatment with the different agents and formulations for 24 h and 72 h. Therefore, the nanoparticles are potentially suitable for the treatment of advanced prostate cancer.

Towards optimal heterogeneous prostate radiotherapy dose prescriptions based on patient-specific or population-based biological features.

Escalation of prescribed dose in prostate cancer (PCa) radiotherapy enables improvement in tumor control at the expense of increased toxicity. Opportunities for reduction of treatment toxicity may emerge if more efficient dose escalation can be achieved by redistributing the prescribed dose distribution according to the known heterogeneous, spatially-varying characteristics of the disease. To examine the potential benefits, limitations and characteristics of heterogeneous boost dose redistribution in PCa radiotherapy based on patient-specific and population-based spatial maps of tumor biological features. High-resolution prostate histology images, from a cohort of 63 patients, annotated with tumor location and grade, provided patient-specific "maps" and a population-based "atlas" of cell density and tumor probability. Dose prescriptions were derived for each patient based on a heterogeneous redistribution of the boost dose to the intraprostatic lesions, with the prescription maximizing patient tumor control probability (TCP). The impact on TCP was assessed under scenarios where the distribution of population-based biological data was ignored, partially included, or fully included in prescription generation. Heterogeneous dose prescriptions were generated for three combinations of maps and atlas, and for conventional fractionation (CF), extreme hypo-fractionation (EH), moderate hypo-fractionation (MH), and whole Pelvic RT+SBRT Boost (WPRT+SBRT). The predicted efficacy of the heterogeneous prescriptions was compared with equivalent homogeneous dose prescriptions. TCPs for heterogeneous dose prescriptions were generally higher than those for homogeneous dose prescriptions. TCP escalation by heterogeneous dose prescription was the largest for CF. When only using population-based atlas data, the generated heterogeneous dose prescriptions of 55 to 58 patients (out of 63) had a higher TCP than for the corresponding homogeneous dose prescriptions. The TCPs of the heterogeneous dose prescriptions generated with the population-based atlas and tumor probability maps did not differ significantly from those using patient-specific biological information. The generated heterogeneous dose prescriptions achieved significantly higher TCP than homogeneous dose prescriptions in the posterior section of the prostate. Heterogeneous dose prescriptions generated via biologically-optimized dose redistribution can produce higher TCP than the homogeneous dose prescriptions for the majority of the patients in the studied cohort. For scenarios where patient-specific biological information was unavailable or partially available, the generated heterogeneous dose prescriptions can still achieve TCP improvement relative to homogeneous dose prescriptions.

Case Report: Prostate adenocarcinoma presented with inguinal lymph node metastasis

Prostate cancer has the highest chance of spreading to the bones. After pelvic and bone involvement, pulmonary metastases and extensive lymphadenopathy are expected consequences. Some men with prostate cancer develop symptomatic metastatic lung lesions and lymphadenopathy despite the absence of other signs of distant spread. Prostate cancer is exceedingly common and the leading cause of cancer in males. Prostate cancer patients with metastases account for half of all cases. In some cases, it occurs in the peritoneum but can also invade the surrounding structures, the bladder, seminal vesicles, and urinary sphincters. For example, we report the case of a 62-year-old man who presented to our hospital with inguinal swelling as his primary symptom. The patient has a history of constipation, burning micturition, and weight loss. The patient was advised of ultrasonography (U.S.G.) abdominonopelvic, which revealed enlarged, irregular, heterogeneous prostate and cystitis and multiple hepatic metastases. Also, there was a lobulated mass lesion in the inguinal canal. The most common spread occurs in bone and lymph nodes. It's uncommon to witness inguinal lymph node metastasis without pelvic lymphadenopathy or other metastasis. The spread occurs usually through a hematogenous, lymphatic, or direct route. Hence this one is a rare presentation. One possible explanation might be abnormal or aberrant lymphatic drainage of the prostate to the inguinal lymph node.

Federated Learning for Medical Imaging Segmentation via Dynamic Aggregation on Non-IID Data Silos

A large number of mobile devices, smart wearable devices, and medical and health sensors continue to generate massive amounts of data, making edge devices’ data explode and making it possible to implement data-driven artificial intelligence. However, the “data silos” and other issues still exist and need to be solved. Fortunately, federated learning (FL) can deal with “data silos” in the medical field, facilitating collaborative learning across multiple institutions without sharing local data and avoiding user concerns about data privacy. However, it encounters two main challenges in the medical field. One is statistical heterogeneity, also known as non-IID (non-independent and identically distributed) data, i.e., data being non-IID between clients, which leads to model drift. The second is limited labeling because labels are hard to obtain due to the high cost and expertise requirement. Most existing federated learning algorithms only allow for supervised training settings. In this work, we proposed a novel federated learning framework, MixFedGAN, to tackle the above issues in federated networks with dynamic aggregation and knowledge distillation. A dynamic aggregation scheme was designed to reduce the impact of current low-performing clients and improve stability. Knowledge distillation was introduced into the local generator model with a new distillation regularization loss function to prevent essential parameters of the global generator model from significantly changing. In addition, we considered two scenarios under this framework: complete annotated data and limited labeled data. An experimental analysis on four heterogeneous COVID-19 infection segmentation datasets and three heterogeneous prostate MRI segmentation datasets verified the effectiveness of the proposed federated learning method.

98P Induction of aggressive phenotype in a heterogeneous prostate cancer model

Prostate cancer (PCa) is one of the main causes of death in men all over the world. To date, the emerging issue is the search for new diagnostic and prognostic biomarkers to distinguish patients with different risk types. Recent studies of PCa biomarkers have drawn attention to the remarkable heterogeneity of this tumor. Tumor heterogeneity (TH) is the main limitation of the ability to use biomarkers’ gene panels in clinics because of different cell subclones within one tumor.

Dynamic boundary-insensitive loss for magnetic resonance medical image segmentation.

A deep learning method has achieved great success in MR medical image segmentation. One challenge in applying deep learning segmentation models to clinical practice is their poor generalization mainly due to limited labeled training samples, inter-site heterogeneity of different datasets, and ambiguous boundary definition, etc. The objective of this work is to develop a dynamic boundary-insensitive (DBI) loss to address this poor generalization caused by an uncertain boundary. The DBI loss is designed to assign higher penalties to misclassified voxels farther from the boundaries in each training iteration to reduce the sensitivity of the segmentation model to the uncertain boundary. The weighting factor of the DBI loss can be adjusted adaptively without any manual setting and adjustment. Extensive experiments were conducted to verify the performance of our DBI loss and its variant, DiceDBI, on four heterogeneous prostate MRI datasets for prostate zonal segmentation and whole prostate segmentation. Experimental results show that our DBI loss, when combined with Dice loss, outperforms all competing loss functions in dice similarity coefficient (DSC) and improves the segmentation performance across all datasets consistently, especially on unseen datasets and when segmenting small or narrow targets. The proposed DiceDBI loss will be valuable for enhancement of the generalization performance of the segmentation model.

A Personalized Genomics Approach of the Prostate Cancer.

Decades of research identified genomic similarities among prostate cancer patients and proposed general solutions for diagnostic and treatments. However, each human is a dynamic unique with never repeatable transcriptomic topology and no gene therapy is good for everybody. Therefore, we propose the Genomic Fabric Paradigm (GFP) as a personalized alternative to the biomarkers approach. Here, GFP is applied to three (one primary—“A”, and two secondary—“B” & “C”) cancer nodules and the surrounding normal tissue (“N”) from a surgically removed prostate tumor. GFP proved for the first time that, in addition to the expression levels, cancer alters also the cellular control of the gene expression fluctuations and remodels their networking. Substantial differences among the profiled regions were found in the pathways of P53-signaling, apoptosis, prostate cancer, block of differentiation, evading apoptosis, immortality, insensitivity to anti-growth signals, proliferation, resistance to chemotherapy, and sustained angiogenesis. ENTPD2, AP5M1 BAIAP2L1, and TOR1A were identified as the master regulators of the “A”, “B”, “C”, and “N” regions, and potential consequences of ENTPD2 manipulation were analyzed. The study shows that GFP can fully characterize the transcriptomic complexity of a heterogeneous prostate tumor and identify the most influential genes in each cancer nodule.

MS-Net: Multi-Site Network for Improving Prostate Segmentation With Heterogeneous MRI Data.

Automated prostate segmentation in MRI is highly demanded for computer-assisted diagnosis. Recently, a variety of deep learning methods have achieved remarkable progress in this task, usually relying on large amounts of training data. Due to the nature of scarcity for medical images, it is important to effectively aggregate data from multiple sites for robust model training, to alleviate the insufficiency of single-site samples. However, the prostate MRIs from different sites present heterogeneity due to the differences in scanners and imaging protocols, raising challenges for effective ways of aggregating multi-site data for network training. In this paper, we propose a novel multi-site network (MS-Net) for improving prostate segmentation by learning robust representations, leveraging multiple sources of data. To compensate for the inter-site heterogeneity of different MRI datasets, we develop Domain-Specific Batch Normalization layers in the network backbone, enabling the network to estimate statistics and perform feature normalization for each site separately. Considering the difficulty of capturing the shared knowledge from multiple datasets, a novel learning paradigm, i.e., Multi-site-guided Knowledge Transfer, is proposed to enhance the kernels to extract more generic representations from multi-site data. Extensive experiments on three heterogeneous prostate MRI datasets demonstrate that our MS-Net improves the performance across all datasets consistently, and outperforms state-of-the-art methods for multi-site learning.

Materials-Based Approach for Interrogating Human Prostate Cancer Cell Adhesion and Migratory Potential Using a Fluoroalkylsilica Culture Surface.

OPCT-1 is a heterogeneous prostate cancer cell line derived from primary (rather than metastatic) disease which contains epithelial, mesenchymal, and CD44high/CD24low cancer stem cell (CSC) subpopulations and from which we have previously generated and characterized stable mesenchymal (P4B6B) and epithelial (P5B3) cell subpopulations. In this contribution, we explore the effect of tissue culture surface chemistry (standard tissue culture plastic (TCP) and a fluoroalkylsilica (FS) culture surface with inherently low surface energy) on the phenotype and adherent capacity of mesenchymal and epithelial cell populations. We demonstrate that OPCT-1 cells adherent to FS surfaces comprise both epithelial- and mesenchymal-like populations; a mesenchymal subpopulation derived from OPCT1 (P4B6B) poorly adheres to FS and formed spheroids, whereas an epithelial subpopulation derived from OPCT1 (P5B3) forms an adherent monolayer. In contrast, P4B6B cells do adhere to FS when cocultured with P5B3 cells. Taken together, these findings demonstrate that EMT/cell differentiation status dictates cell adhesive capacity and provide a novel insight into the relationship between epithelial and mesenchymal cell populations in metastasis. Importantly, the differences in adherence capacity between P4B6B and P5B3 are not apparent using standard TCP-based culture, thereby highlighting the value of using alternative culture surfaces for studying cell surface interaction/adhesion phenomena and interrogating mechanisms involved in adhesion and detachment of metastatic tumor cells.

Development of Bispecific NT-PSMA Heterodimer for Prostate Cancer Imaging: A Potential Approach to Address Tumor Heterogeneity

Prostate cancer is a heterogeneous disease with a poor survival rate at late stage. In this report, a dual targeting PET agent was developed to partially address the tumor heterogeneity issue. The heterodimer F-BCN-PSMA-NT was designed to target PSMA and neurotensin receptor1 (NTR1), both of which have demonstrated great potential in prostate cancer management. The heterodimer was synthesized through the conjugation of Glu-urea-lys(Ahx) (PSMA targeting motif) and NT20.3 (NTR1 targeting motif) to a symmetric trifunctional linker, bearing an azide group for further modification. Radio-labeling was performed using strain promoted azide-alkyne click reaction with high yield. Cell based assays suggested that F-BCN-PSMA-NT has comparable or only slightly reduced binding affinity with the corresponding monomers. Small animal PET clearly demonstrated that the heterodimer probe has prominent uptake not only in NTR1 positive/PSMA negative PC-3 tumors (1.4 ± 0.3%ID/g), but also in the PSMA positive/NTR1 negative LnCap tumors (1.3 ± 0.2%ID/g). The tracer showed comparable tumor to background ratio with each monomer. In summary, prostate cancer is a heterogeneous disease in need of improved diagnostics and treatments. The PSMA-NT heterodimer represents a new class of molecules that can be used to target two distinct antigens related to prostate cancer. In addition to the imaging applications demonstrated in this study, the agent also holds great potential on the treatment of heterogeneous prostate cancer.

DIAGNOSING MILLIARY MYCOBACTERIUM BOVIS FROM THE PROSTATE OF AN IMMUNOCOMPETENT HOST

SESSION TITLE: Chest Infections 1 SESSION TYPE: Med Student/Res Case Report PRESENTED ON: 10/09/2018 03:45 PM - 04:45 PM INTRODUCTION: Zoonotic infection from Mycobacterium Bovis remains an important consideration for tuberculous disease in the developing world. We present a challenging case of hematogenous Mycobacterial dissemination from an uncommon culprit. CASE PRESENTATION: A 53 year old Bacillus-Calmette-Guerin (BCG) vaccinated and otherwise healthy Mexican male presented with complaints of fever, productive cough, arthralgias and weight loss over the preceding 21 days. He had already completed two separate outpatient courses of oral antibiotics without improvement. He denied any travel outside of the continental United States over the last 13 years and denied any recent sick contacts. He also owned 2 pet parrots. His physical exam and initial laboratory work up was unremarkable. A Chest X-ray (Fig. 1) revealed diffuse, bilateral, micronodular opacities, warranting further evaluation with Computed Tomography (CT) (Fig. 2). Initial acid-fast bacilli (AFB) sputum stains, bronchoalveolar lavage stains, cytology brushings and trans-bronchial biopsies were all negative. Hypersensitivity pneumonitis and opportunistic fungal panels were obtained which were unremarkable. Interferon gamma release assay was positive however equivocal given patient's BCG vaccination status. CT Chest, Abdomen and Pelvis (Fig. 3) was performed, which incidentally revealed an enlarged, heterogeneous prostate with fluid collections. Ultrasound guided aspiration of the prostate yielded pus and a strongly positive AFB smear. Eventually, the AFB cultures from the initial BAL came back positive. The patient was started on RIPE therapy with symptomatic improvement. Final speciation returned as M. Bovis and accordingly, pyrazinamide was stopped. DISCUSSION: M. bovis disease was common in the industrialized world before the practice of pasteurization became widely implemented in the 1940s. Current estimates in the USA and Europe identify between 1.3%-1.6% of tuberculosis cases attributable to M. Bovis. Infections are typically contracted via ingestion of unpasteurized dairy products from infected livestock and may remain dormant for many years, as was likely the situation in this case. Given the oral inoculation route, most cases of M.bovis manifest primarily with extrapulmonary findings. Of note, M. Bovis has documented intrinsic resistance to pyrazinamide which necessitates modification of typical RIPE treatment strategy. CONCLUSIONS: Diagnosis of disseminated TB remains a challenge. Regarding M. Bovis, the mean time to diagnosis has increased among practitioners given the diminishing incidence of infection. Vigilance of the disseminated and often extra-pulmonary form of tuberculosis caused by M. Bovis continues to be warranted. Patients at particular risk for M.bovis are those from developing countries, with frequent exposure to livestock and/or the practice of unpasteurized dairy product consumption. Reference #1: Scott. C. Human Tuberculosis Caused by Mycobacterium bovis in the United States, 2006-2013. Clin Infect Dis. 2016 Sep 1;63(5):594-601. Reference #2: Sherman LF. Patient and health care system delays in the diagnosis and treatment of tuberculosis. Int J Tuberc Lung Dis. 1999 Dec;3(12):1088-95. Reference #3: Majoor, C.J. Epidemiology of Mycobacterium bovis disease in humans, The Netherlands, 1993-2007. Emerg Infect Dis. 2011 Mar;17(3):457-63. DISCLOSURES: no disclosure on file for Christopher Barrios; No relevant relationships by Armin Krvavac, source=Web Response No relevant relationships by Scott Maughan, source=Web Response No relevant relationships by Pujan Patel, source=Web Response

Model-driven discovery of long-chain fatty acid metabolic reprogramming in heterogeneous prostate cancer cells.

Epithelial-mesenchymal-transition promotes intra-tumoral heterogeneity, by enhancing tumor cell invasiveness and promoting drug resistance. We integrated transcriptomic data for two clonal subpopulations from a prostate cancer cell line (PC-3) into a genome-scale metabolic network model to explore their metabolic differences and potential vulnerabilities. In this dual cell model, PC-3/S cells express Epithelial-mesenchymal-transition markers and display high invasiveness and low metastatic potential, while PC-3/M cells present the opposite phenotype and higher proliferative rate. Model-driven analysis and experimental validations unveiled a marked metabolic reprogramming in long-chain fatty acids metabolism. While PC-3/M cells showed an enhanced entry of long-chain fatty acids into the mitochondria, PC-3/S cells used long-chain fatty acids as precursors of eicosanoid metabolism. We suggest that this metabolic reprogramming endows PC-3/M cells with augmented energy metabolism for fast proliferation and PC-3/S cells with increased eicosanoid production impacting angiogenesis, cell adhesion and invasion. PC-3/S metabolism also promotes the accumulation of docosahexaenoic acid, a long-chain fatty acid with antiproliferative effects. The potential therapeutic significance of our model was supported by a differential sensitivity of PC-3/M cells to etomoxir, an inhibitor of long-chain fatty acid transport to the mitochondria.

Abstract 2702: Mutations of SPOP, FOXA1 and IDH1 are associated with prostate cancer metastasis and biochemical outcomes

Abstract Recent genomic studies have shed light on cataloging genomic alterations in prostate cancer. Mechanistic studies allow the use of this information to subclassify the heterogeneous prostate tumors for optimized treatment planning. Speckle-Type POZ Protein (SPOP), Forkhead Box Protein A1 (FOXA1) and Isocitrate Dehydrogenase 1 (IDH1) are among the genes that show frequent point mutations in primary prostate cancers. However, the clinical significance of these gene mutations in cancer patients is less clear. To determine the whether SPOP, FOXA1 and IDH1 mutations are associated with clinical outcomes in prostate cancer, we pyro-sequenced the three genes in prostate cancer patients and evaluated the clinical and prognostic significance. 198 patients from the first hospital of Xi’An Jiaotong University (China) were analyzed. All patients were newly diagnosed with prostate cancer from January 2010 to December 2015. No patient was lost to follow-up. The average follow-up time after the primary diagnosis was 27 months. The Fisher’s exact tests were used to compare categorical data. The risk of metastasis among patients with SPOP, FOXA1 and IDH1 mutations was evaluated using univariate and multivariate logistic regression models. The prognostic significance of clinical and gene mutations was determined using multivariate Cox regression analysis. SPOP mutations were found in 16 patients (8.1%), with all of the mutations clustered in the substrate-binding MATH domain. FOXA1 mutationswere found in nine patients (4.5%), and were clustered in the Forkhead domain. IDH1 mutations were detected in three patients (1.5%). Mutation frequencies of SPOP, FOXA1 and IDH1 were associated with prostate-specific antigen (PSA), a biochemical marker of prostate tumor presence/risk which is decided by Gleason Score, T stage and PSA level, along with prostate cancer PSA failure and metastasis. Among patients with SPOP mutation, 56.3% showed metastasis at the time of diagnosis of primary cancer, compared to only 11.5% of patients with wild-type SPOP. Similarly, the probabilities of FOXA1 and IDH1 mutations with metastasis were approximately 44.4% and 66.7% versus 13.8% and 14.4%, respectively, comparing to their wild-type counterparts. The metastasis risk for patients with SPOP mutation was 1.27 times of the SPOP wild-type patients (P = 0.003). We also found that patients with SPOP (P < 0.0001) and FOXA1 (P = 0.0403) mutations showed higher risk of PSA failure compared with wild-type. The PSA failure risk for patients with SPOP mutation was 35.49 times of the SPOP wild-type patients. In contrast, IDH1 mutation was not associated with PSA failure (P = 0.054). Multivariate analyses demonstrate that SPOP mutation is an independent factor that is associated with prostate cancer metastasis and PSA failure recurrence. These findings underscore the clinical significance for profiling SPOP, FOXA1 and IDH1. Note: This abstract was not presented at the meeting. Citation Format: Jinlu Ma, Suxia Han, Xin Sui, Wenyan Lu, Yonghe Li, Bo Xu. Mutations of SPOP, FOXA1 and IDH1 are associated with prostate cancer metastasis and biochemical outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2702. doi:10.1158/1538-7445.AM2017-2702

5-year outcomes from a prospective multi-institutional trial of heterogeneous dosing stereotactic body radiotherapy (SBRT) for low- and intermediate-risk prostate cancer.

35 Background: SBRT is an emerging treatment for prostate cancer, but long-term reporting remains sparse. We present a prospective Phase II trial with 90% treated in community facilities. Methods: 14 institutions enrolled 259 patients - 112 low-risk; 147 intermediate-risk. The regimen emulated a high-dose rate brachytherapy (HDR) regimen - 38 Gy/4 fractions delivered by robotic SBRT. Androgen deprivation therapy was not allowed. HDR-like heterogeneous prostate dosing was used (Dmax >57 Gy). Toxicities were assessed by CTCAE v3.0 and quality of life assessed by Expanded Prostate Cancer Index Composite (EPIC). Biochemical recurrence was defined by Phoenix criteria. Results: Median follow-up is 5 years. 5-yr Grade 2 GU toxicity was 13.7% and GI toxicity 4.5%, with Grade 3 rates of 3% (GU) and 0% (GI) (one Gd 4 GU event). 5-yr median PSA was 0.1 ng/mL with further subsequent decrease (7 y = 0.035 ng/mL). 5-yr biochemical disease-free survival (bDFS) = 100% for low-risk and 88.5% for int-risk. 6 patients developed distant metastasis and one died of disease. Median EPIC GU obstruction and GI scores were similar at baseline vs. 5 years. 2% of patients had baseline GU incontinence requiring pad use vs 10% at 5 yrs. Of baseline potent men, 46% remained so at 5 yrs (66.7% for those age ≤65 vs. 37.1% age >65 at treatment). Conclusions: This is the first report of 5-year median follow-up outcomes post heterogeneous dosing SBRT for early prostate cancer. This treatment produces a low PSA nadir vs other forms of radiotherapy, with a favorable long-term result that appears reproducible in the community. Clinical trial information: 00643617. [Table: see text]

Abstract A29: Heterogeneity of androgen receptor dynamics and drug response in prostate cancer cells

Abstract Background: Recent studies suggest that the spatio-temporal dynamics of critical signaling molecules can mediate heterogeneous response to therapeutic intervention. Here, we set out to apply live cell imaging of single cells in high throughput to correlate the dynamics of androgen receptor (AR) with response to taxane chemotherapy in heterogeneous prostate cancer (PCa) cell populations. Methods: We previously developed a 3-step high throughput imaging and data analysis workflow to improve measurements of the dynamic phenotype in heterogeneous populations. We treated PCa cells stably expressing GFP-AR with AR ligand and quantified nuclear/cytoplasmic GFP intensity to measure nuclear translocation of AR over a 30 min time course. Then we treated cells with paclitaxel and tracked cells' response for 24h. Results: Applied to PCa cell lines stably expressing GFP-AR, we measured considerable heterogeneity of AR translocation in response to ligand stimulation. We quantified populations of non-responders and classified responding cells based on the dynamics of AR. Evaluation of cell morphology revealed a fraction of relatively large cells to be exclusively slow responders to AR ligand. We measured heterogeneous response to treatment with paclitaxel that correlated with cell phenotype. Conclusion: We conclude that cell morphology features in heterogeneous PCa cell populations correlate with AR translocation dynamics and drug response. Future experiments will include expression of the constitutively active AR variant AR-v7 to analyze its effect on the dynamics of wild-type AR and on single cell response to paclitaxel chemotherapy. Note: This abstract was not presented at the conference. Citation Format: Katherin Patsch, Anjana Soundararajan, Mark Engeln, Mitchell E. Gross, Shannon M. Mumenthaler, Daniel Ruderman. Heterogeneity of androgen receptor dynamics and drug response in prostate cancer cells. [abstract]. In: Proceedings of the AACR Special Conference on Engineering and Physical Sciences in Oncology; 2016 Jun 25-28; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2017;77(2 Suppl):Abstract nr A29.

Cooperation among heterogeneous prostate cancer cells in the bone metastatic niche.

The growth of disseminated tumor cells (DTCs) into metastatic lesions depends on the establishment of a favorable microenvironment in the stroma of the target organs. Here we show that mice treated with anakinra, an antagonist of the IL-1β receptor (IL-1R), or harboring a targeted deletion of IL-1R are significantly less prone to develop bone tumors when inoculated in the arterial circulation with human prostate cancer (PCa) cells expressing IL-1β. Interestingly, human mesenchymal stem cells (hMSCs) exposed in vitro to medium conditioned by IL-1β-expressing cancer cells responded by up regulating S100A4, a marker of cancer-associated fibroblasts (CAFs), and this effect was blocked by anakinra. Analogously, the stroma adjacent to skeletal metastases generated in mice by IL-1β-expressing cancer cells showed a dramatic increase in S100A4, COX-2 and the alteration of thirty tumor-related genes as measured by Nanostring analysis. These effects were not observed in the stroma associated to the rare and much smaller metastases generated by the same cells in IL-1R knockout animals, confirming that tumor-secreted IL-1β generates skeletal CAFs and conditions the surrounding bone microenvironment. In skeletal lesions from patients with metastatic PCa, histological and molecular analyses revealed that IL-1β is highly expressed in cancer cells in which the androgen receptor (AR) is not detected (AR−) whereas this cytokine is uniformly absent in the AR-positive (AR+) metastatic cells. The stroma conditioned by IL-1β-expressing cancer cells served as a supportive niche also for coexisting IL-1β-lacking cancer cells, which are otherwise unable to generate tumors after independently seeding the skeleton of mice. This niche is established very early following tumor seeding and hints to a role of IL-1β in promoting early colonization of PCa at the skeletal level.

MP62-13 NOVEL IN VIVO MODEL FOR COMBINATORIAL FLUORESCENCE LABELING IN MOUSE PROSTATE

You have accessJournal of UrologyProstate Cancer: Basic Research & Pathophysiology I1 Apr 2016MP62-13 NOVEL IN VIVO MODEL FOR COMBINATORIAL FLUORESCENCE LABELING IN MOUSE PROSTATE Xiaolan Fang, Michael B. Rothberg, Kenneth Gyabaah, Bita Nick Kholgh, J. Marc Cline, and K.C. Balaji Xiaolan FangXiaolan Fang More articles by this author , Michael B. RothbergMichael B. Rothberg More articles by this author , Kenneth GyabaahKenneth Gyabaah More articles by this author , Bita Nick KholghBita Nick Kholgh More articles by this author , J. Marc ClineJ. Marc Cline More articles by this author , and K.C. BalajiK.C. Balaji More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.921AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Currently, few animal models exist to study the cellular origin of normal or neoplastic development in the prostate by tracing multiple cell lineages in vivo. We previously described a mouse model that expresses fluorescent proteins (XFPs) for normal tissue, benign hyperplasia, and primary neoplasia in the prostate. We have since developed this model to demonstrate more advanced forms of prostate cancer to facilitate the treatment of heterogeneous prostate diseases by targeting individual cell lineages. METHODS Using an in vivo stochastic fluorescent protein combinatorial strategy, XFP signals were expressed specifically in the prostate of: (1) Protein Kinase D1 (PKD1) knock-out, K-Ras G12D knock-in, (2) Phosphatase and tensin homolog (PTEN) knock-out, K-Ras G12D knock-in, and (3) K-Ras G12D knock-in, PTEN PKD1 knock-out triple mutant mice under the control of the prostate-specific Probasin (PB) promoter. RESULTS In vivo XFP signals were observed in the prostate of (1) PKD1 knock-out, K-Ras G12D knock-in, (2) PTEN knock-out, K-Ras G12D knock-in, and (3) K-Ras G12D knock-in, PTEN PKD1 knock-out triple mutant mice, which developed prostate cancer sporadically invading the urethra and micro-metastasis to the lung, in situ carcinoma aggressively invading the urethra, and a highly aggressive prostate cancer resulting in early animal death, respectively. The unique expression pattern of XFPs in neoplastic tissue indicated the clonal origin of cancer cells in the prostate. CONCLUSIONS This transgenic mouse model demonstrates combinatorial fluorescent protein expression in locally aggressive and metastatic cancerous prostatic tissues. This novel prostate-specific fluorescent-labeled mouse model, which we named Prorainbow, could be useful in studying benign and malignant pathology of the prostate. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e817 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Xiaolan Fang More articles by this author Michael B. Rothberg More articles by this author Kenneth Gyabaah More articles by this author Bita Nick Kholgh More articles by this author J. Marc Cline More articles by this author K.C. Balaji More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Combined Tumor Suppressor Defects Characterize Clinically Defined Aggressive Variant Prostate Cancers.

Morphologically heterogeneous prostate cancers that behave clinically like small-cell prostate cancers (SCPC) share their chemotherapy responsiveness. We asked whether these clinically defined, morphologically diverse, "aggressive variant prostate cancer (AVPC)" also share molecular features with SCPC. Fifty-nine prostate cancer samples from 40 clinical trial participants meeting AVPC criteria, and 8 patient-tumor derived xenografts (PDX) from 6 of them, were stained for markers aberrantly expressed in SCPC. DNA from 36 and 8 PDX was analyzed by Oncoscan for copy number gains (CNG) and losses (CNL). We used the AVPC PDX to expand observations and referenced publicly available datasets to arrive at a candidate molecular signature for the AVPC. Irrespective of morphology, Ki67 and Tp53 stained ≥10% cells in 80% and 41% of samples, respectively. RB1 stained <10% cells in 61% of samples and AR in 36%. MYC (surrogate for 8q) CNG and RB1 CNL showed in 54% of 44 samples each and PTEN CNL in 48%. All but 1 of 8 PDX bore Tp53 missense mutations. RB1 CNL was the strongest discriminator between unselected castration-resistant prostate cancer (CRPC) and the AVPC. Combined alterations in RB1, Tp53, and/or PTEN were more frequent in the AVPC than in unselected CRPC and in The Cancer Genome Atlas samples. Clinically defined AVPC share molecular features with SCPC and are characterized by combined alterations in RB1, Tp53, and/or PTEN.

Dose-Escalated Stereotactic Body Radiation Therapy for Patients With Intermediate- and High-Risk Prostate Cancer: Initial Dosimetry Analysis and Patient Outcomes

To report the short-term clinical outcomes and acute and late treatment-related genitourinary (GU) and gastrointestinal (GI) toxicities in patients with intermediate- and high-risk prostate cancer treated with dose-escalated stereotactic body radiation therapy (SBRT). Between 2011 and 2014, 24 patients with prostate cancer were treated with SBRT to the prostate gland and proximal seminal vesicles. A high-dose avoidance zone (HDAZ) was created by a 3-mm expansion around the rectum, urethra, and bladder. Patients were treated to a minimum dose of 36.25Gy in 5 fractions, with a simultaneous dose escalation to a dose of 50Gy to the target volume away from the HDAZ. Acute and late GU and GI toxicity outcomes were measured according to the National Cancer Institute Common Terminology Criteria for Adverse Events toxicity scale, version4. The median follow-up was 25months (range, 18-45months). Nine patients (38%) experienced an acute grade 2 GU toxicity, which was medically managed, and no patients experienced an acute grade 2 GI toxicity. Two patients (8%) experienced late grade 2 GU toxicity, and 2 patients (8%) experienced late grade 2 GI toxicity. No acute or late grade ≥3 GU or GI toxicities were observed. The 24-month prostate-specific antigen relapse-free survival outcome for all patients was 95.8% (95% confidence interval 75.6%-99.4%), and both biochemical failures occurred in patients with high-risk disease. All patients are currently alive at the time of this analysis and continue to be followed. A heterogeneous prostate SBRT planning technique with differential treatment volumes (low dose: 36.25Gy; and high dose: 50Gy) with an HDAZ provides a safe method of dose escalation. Favorable rates of biochemical control and acceptably low rates of acute and long-term GU and GI toxicity can be achieved in patients with intermediate- and high-risk prostate cancer treated with SBRT.

Effect of material property heterogeneity on biomechanical modeling of prostate under deformation

Biomechanical model based deformable image registration has been widely used to account for prostate deformation in various medical imaging procedures. Biomechanical material properties are important components of a biomechanical model. In this study, the effect of incorporating tumor-specific material properties in the prostate biomechanical model was investigated to provide insight into the potential impact of material heterogeneity on the prostate deformation calculations. First, a simple spherical prostate and tumor model was used to analytically describe the deformations and demonstrate the fundamental effect of changes in the tumor volume and stiffness in the modeled deformation. Next, using a clinical prostate model, a parametric approach was used to describe the variations in the heterogeneous prostate model by changing tumor volume, stiffness, and location, to show the differences in the modeled deformation between heterogeneous and homogeneous prostate models. Finally, five clinical prostatectomy examples were used in separately performed homogeneous and heterogeneous biomechanical model based registrations to describe the deformations between 3D reconstructed histopathology images and ex vivo magnetic resonance imaging, and examine the potential clinical impact of modeling biomechanical heterogeneity of the prostate. The analytical formulation showed that increasing the tumor volume and stiffness could significantly increase the impact of the heterogeneous prostate model in the calculated displacement differences compared to the homogeneous model. The parametric approach using a single prostate model indicated up to 4.8 mm of displacement difference at the tumor boundary compared to a homogeneous model. Such differences in the deformation of the prostate could be potentially clinically significant given the voxel size of the ex vivo MR images (0.3 × 0.3 × 0.3 mm). However, no significant changes in the registration accuracy were observed using heterogeneous models for the limited number of clinical prostatectomy patients modeled and evaluated in this study.