Contemporary prostate cancer treatment choices in multidisciplinary clinics referenced to national trends.

BACKGROUND: The purpose of this study was to assess treatment choices among men with prostate cancer who presented at The University of Texas MD Anderson Cancer Center multidisciplinary (MultiD) clinic compared with nationwide trends. METHODS: In total, 4451 men with prostate cancer who presented at the MultiD clinic from 2004 to 2016 were analyzed. To assess nationwide trends, the authors analyzed 392,710 men with prostate cancer who were diagnosed between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. The primary endpoint was treatment choice as a function of pretreatment demographics. RESULTS: Univariate analyses revealed similar treatment trends in the MultiD and SEER cohorts. The use of procedural forms of definitive therapy decreased with age, including brachytherapy and prostatectomy (all P < .05). Later year of diagnosis/clinic visit was associated with decreased use of definitive treatments, whereas higher risk grouping was associated with increased use (all P < .001). Patients with low-risk disease treated at the MultiD clinic were more likely to receive nondefinitive therapy than patients in SEER, whereas the opposite trend was observed for patients with high-risk disease, with a substantial portion of high-risk patients in SEER not receiving definitive therapy. In the MultiD clinic, African American men with intermediate-risk and high-risk disease were more likely to receive definitive therapy than white men, but for SEER the opposite was true. CONCLUSIONS: Presentation at a MultiD clinic facilitates the appropriate disposition of patients with low-risk disease to nondefinitive strategies of patients with high-risk disease to definitive treatment, and it may obviate the influence of race.

Prostate Cancer Energetics and Biosynthesis.

Cancers must alter their metabolism to satisfy the increased demand for energy and to produce building blocks that are required to create a rapidly growing tumor. Further, for cancer cells to thrive, they must also adapt to an often changing tumor microenvironment, which can present new metabolic challenges (ex. hypoxia) that are unfavorable for most other cells. As such, altered metabolism is now considered an emerging hallmark of cancer. Like many other malignancies, the metabolism of prostate cancer is considerably different compared to matched benign tissue. However, prostate cancers exhibit distinct metabolic characteristics that set them apart from many other tumor types. In this chapter, we will describe the known alterations in prostate cancer metabolism that occur during initial tumorigenesis and throughout disease progression. In addition, we will highlight upstream regulators that control these metabolic changes. Finally, we will discuss how this new knowledge is being leveraged to improve patient care through the development of novel biomarkers and metabolically targeted therapies.

Quality of life after brachytherapy or bilateral nerve-sparing robot-assisted radical prostatectomy for prostate cancer: a prospective cohort.

OBJECTIVE: To provide comparative data on quality of life (QoL) after prostate cancer treatment to help patients make an informed decision regarding their choice of treatment. METHODS: Patients with pathologically proven, non-metastatic, T1-T3bN0 prostate cancer were included in this prospective non-randomized study if they were to receive treatment with curative intent. Sample size was at least 181 patients per cohort/treatment type. QoL was recorded at baseline and at each follow-up using the Expanded Prostate Cancer Index Composite (EPIC) instrument. The minimal clinically important difference was defined as half of the standard deviation of the baseline score for each domain. A mixed effects model was used to compare the different treatments. Data are presented on the brachytherapy and the bilateral nerve-sparing robot-assisted radical prostatectomy (RARP) cohorts. Hormonotherapy was not allowed. RESULTS: Between November 2007 and January 2013, 181 patients who received brachytherapy and 210 patients who underwent RARP were included. Of the patients who underwent RARP, 178 had bilateral nerve-sparing and were included in the present analysis. Response rate to EPIC questionnaires were higher in the brachytherapy than in the RARP arm: 82% vs 57% at 2 years after treatment and 55% vs 45% at 4 years after treatment. In the mixed effects model, patients in the RARP arm had better QoL with regard to urinary irritation/obstruction or bother and bowel function, and lower QoL regarding sexual function and urinary incontinence. Results were confirmed in a propensity score-matched model. Patient satisfaction was significantly higher in the brachytherapy group at 1, 2 and 3 years after treatment. CONCLUSION: This prospective non-randomized study shows long-term differences in QoL domains after bilateral nerve-sparing RARP and brachytherapy. Differences in patient satisfaction should be further explored. These results could be used to counsel patients in the decision-making process.

Mitochondrial Activity in Human White Adipocytes Is Regulated by the Ubiquitin Carrier Protein 9/microRNA-30a Axis.

The acquisition of beige adipocyte features by white fat cells corresponds to protection against obesity-induced metabolic diseases in humans and animal models of type 2 diabetes. In adipose tissue, expression of the E2 small ubiquitin-like modifier ligase ubiquitin carrier protein 9 (Ubc9) is positively correlated with markers of insulin resistance and corresponds with impaired browning of human white adipocytes. However, the molecular regulation of Ubc9 expression in adipocytes and other cells remains unclear. In this study, we demonstrate that the mRNA and protein expression of Ubc9 are regulated by the microRNA miRNA-30a (miR-30a) in human subcutaneous adipocytes. Ubc9 and miR-30a exhibit inverse expression in adipose tissue, with miR-30a robustly elevated in brown fat. Depletion of Ubc9 by siRNA or enforced expression of a miR-30a mimic augments mitochondrial volume and respiration in human white adipocytes, reflecting features of brown fat cells. Furthermore, Ubc9 depletion induces a brown fat gene program in human subcutaneous adipocytes. Induction of the beige-selective gene program corresponds to stabilization of the PR domain-containing 16 (PRDM16) protein, an obligate transcriptional regulator of the brown/beige fat metabolic program in white adipocytes that interacts with Ubc9. Taken together, our data demonstrate a previously unappreciated molecular axis that controls browning of human white adipocytes.

Analysis of interactions between the epigenome and structural mutability of the genome using Genboree Workbench tools.

BACKGROUND: Interactions between the epigenome and structural genomic variation are potentially bi-directional. In one direction, structural variants may cause epigenomic changes in cis. In the other direction, specific local epigenomic states such as DNA hypomethylation associate with local genomic instability. METHODS: To study these interactions, we have developed several tools and exposed them to the scientific community using the Software-as-a-Service model via the Genboree Workbench. One key tool is Breakout, an algorithm for fast and accurate detection of structural variants from mate pair sequencing data. RESULTS: By applying Breakout and other Genboree Workbench tools we map breakpoints in breast and prostate cancer cell lines and tumors, discriminate between polymorphic breakpoints of germline origin and those of somatic origin, and analyze both types of breakpoints in the context of the Human Epigenome Atlas, ENCODE databases, and other sources of epigenomic profiles. We confirm previous findings that genomic instability in human germline associates with hypomethylation of DNA, binding sites of Suz12, a key member of the PRC2 Polycomb complex, and with PRC2-associated histone marks H3K27me3 and H3K9me3. Breakpoints in germline and in breast cancer associate with distal regulatory of active gene transcription. Breast cancer cell lines and tumors show distinct patterns of structural mutability depending on their ER, PR, or HER2 status. CONCLUSIONS: The patterns of association that we detected suggest that cell-type specific epigenomes may determine cell-type specific patterns of selective structural mutability of the genome.

Prostate-Specific Antigen Response to Androgen Deprivation Therapy in the Neoadjuvant Setting for High-Risk Prostate Adenocarcinoma (PIRANHA): Pooled Analysis of Two Randomized Clinical Trials.

PURPOSE: A suboptimal prostate-specific antigen (PSA) response to neoadjuvant androgen deprivation therapy (ADT) among men who go on to receive definitive radiation therapy for prostate cancer might suggest the existence of castration-resistant disease or altered androgen receptor signaling. This in turn may portend worse long-term clinical outcomes, especially in men with high-risk disease. We set out to evaluate the prognostic impact of poor PSA response to neoadjuvant ADT in men with high-risk prostate cancer. METHODS AND MATERIALS: This was a post hoc analysis of the multicenter TROG 03.04 RADAR and PCS IV randomized clinical trials. Inclusion criteria for this analysis were patients with high-risk prostate cancer (defined as Gleason score ≥8, initial PSA ≥20 ng/mL, or cT3a disease or higher) who received definitive radiation therapy, at least 18 months of ADT, and had a preradiation therapy PSA level drawn after at least 3 months of neoadjuvant ADT. Poor PSA response was defined as PSA >0.5 ng/mL. Cox regression and Fine-Gray models were used to test whether poor PSA response was associated with metastasis-free survival, biochemical recurrence, prostate-cancer specific mortality, and overall survival. RESULTS: Nine hundred thirty men met inclusion criteria for this analysis. Median follow-up was 130 months (interquartile range [IQR], 89-154 months). After a median of 3 months (IQR, 3-4.2 months) of neoadjuvant ADT, the median PSA was 0.60 ng/mL (IQR, 0.29-1.59). Overall, 535 men (57%) had a PSA >0.5 ng/mL. Poor PSA response was associated with significantly worse metastasis-free survival (hazard ratio [HR], 3.93; P = .02), worse biochemical recurrence (subdistribution HR, 2.39; P = .003), worse prostate-cancer specific mortality (subdistribution HR, 1.50; P = .005), and worse overall survival (HR, 4.51; P = .05). CONCLUSIONS: Patients with PSA >0.5 mg/mL after at least 3 months of neoadjuvant ADT had worse long-term clinical outcomes and should be considered for treatment intensification.

Androgen receptor agonism promotes an osteogenic gene program in preadipocytes.

Androgens regulate body composition by interacting with the androgen receptor (AR) to control gene expression in a tissue-specific manner. To identify novel regulatory roles for AR in preadipocytes, we created a 3T3-L1 cell line stably expressing human AR. We found AR expression is required for androgen-mediated inhibition of 3T3-L1 adipogenesis. This inhibition is characterized by decreased lipid accumulation, reduced expression of adipogenic genes, and induction of genes associated with osteoblast differentiation. Collectively, our results suggest androgens promote an osteogenic gene program at the expense of adipocyte differentiation.

BRCA1 promoter methylation status does not predict response to tamoxifen in sporadic breast cancer patients.

The purpose of this study is to investigate whether BRCA1 promoter methylation is associated with poorer outcome in sporadic breast cancer cases treated with tamoxifen. BRCA1 promoter methylation was determined by bisulfite pyrosequencing in two groups of sporadic breast cancer patients, systemically untreated (N = 497) and treated with adjuvant tamoxifen (N = 497). Associations of BRCA1 promoter methylation with clinopathological characteristics and the effect of BRCA1 promoter methylation on time to first recurrence (TTR) and overall survival (OS) were examined. No significant differences were observed between BRCA1 promoter methylation and clinopathological characteristics in untreated and tamoxifen-treated groups. Cut point analysis did not find any promising cut point for BRCA1 promoter methylation that would differentially influence TTR and OS in untreated and tamoxifen-treated group. Using the median (2.53 %) and an arbitrary value of 10 % as a cut point for methylation, we still found no significant effect of BRCA1 promoter methylation on TTR and OS in untreated and tamoxifen-treated group. Despite data suggesting that BRCA1 levels impact estrogen receptor response to tamoxifen, our results indicate that BRCA1 promoter methylation is not associated with poorer outcome in sporadic breast cancer cases treated with tamoxifen.

Tumour metabolism and its unique properties in prostate adenocarcinoma.

Anabolic metabolism mediated by aberrant growth factor signalling fuels tumour growth and progression. The first biochemical descriptions of the altered metabolic nature of solid tumours were reported by Otto Warburg almost a century ago. Now, the study of tumour metabolism is being redefined by the development of new molecular tools, tumour modelling systems and precise instrumentation together with important advances in genetics, cell biology and spectroscopy. In contrast to Warburg's original hypothesis, accumulating evidence demonstrates a critical role for mitochondrial metabolism and substantial variation in the way in which different tumours metabolize nutrients to generate biomass. Furthermore, computational and experimental approaches suggest a dominant influence of the tissue-of-origin in shaping the metabolic reprogramming that enables tumour growth. For example, the unique metabolic properties of prostate adenocarcinoma are likely to stem from the distinct metabolism of the prostatic epithelium from which it emerges. Normal prostatic epithelium employs comparatively glycolytic metabolism to sustain physiological citrate secretion, whereas prostate adenocarcinoma consumes citrate to power oxidative phosphorylation and fuel lipogenesis, enabling tumour progression through metabolic reprogramming. Current data suggest that the distinct metabolic aberrations in prostate adenocarcinoma are driven by the androgen receptor, providing opportunities for functional metabolic imaging and novel therapeutic interventions that will be complementary to existing diagnostic and treatment options.

Association of Sociodemographic and Health-Related Factors With Receipt of Nondefinitive Therapy Among Younger Men With High-Risk Prostate Cancer.

Importance: Multiple randomized clinical trials have shown that definitive therapy improves overall survival among patients with high-risk prostate cancer. However, many patients do not receive definitive therapy because of sociodemographic and health-related factors. Objective: To identify factors associated with receipt of nondefinitive therapy (NDT) among patients aged 70 years and younger with high-risk prostate cancer. Design, Setting, and Participants: This cohort study identified 72 036 patients aged 70 years and younger with high-risk prostate cancer and Charlson Comorbidity Index scores of 2 or less who were entered in the National Cancer Database between January 2004 and December 2014. Data analysis was conducted from November 2018 to December 2019. Exposure: Receipt of NDT as an initial treatment approach. Main Outcomes and Measures: Survival rates were compared based on receipt of definitive therapy or NDT, and sociodemographic and health-related factors were associated with the type of therapy received. Residual life expectancy was estimated from the National Center for Health Statistics to calculate person-years of life lost. Results: A total of 72 036 men with a median (range) age of 63 (30-70) years, Charlson Comorbidity Index scores of 2 or less, and high-risk prostate cancer without regional lymph node or distant metastatic disease were analyzed. Among eligible patients, 5252 (7.3%) received NDT as an initial therapeutic strategy. On univariate and multivariate analyses, NDT was associated with worse overall survival (univariate analysis hazard ratio, 2.54; 95% CI, 2.40-2.69; P < .001; multivariate analysis hazard ratio, 2.40; 95% CI, 2.26-2.56; P < .001). Compared with patients with private insurance or managed care, those with no insurance, Medicaid, or Medicare were more likely to receive systemic therapy only (no insurance: odds ratio [OR], 3.34; 95% CI, 2.81-3.98; P < .001; Medicaid: OR, 2.92; 95% CI, 2.48-3.43; P < .001; Medicare: OR, 1.36; 95% CI, 1.20-1.53; P < .001) or no treatment (no insurance: OR, 2.63; 95% CI, 2.24-3.08; P < .001; Medicaid: OR, 1.71; 95% CI, 1.45-2.01; P < .001; Medicare: OR, 1.14; 95% CI, 1.04-1.24; P = .004). Compared with white patients, black patients were more likely to receive systemic therapy only (OR, 1.93; 95% CI, 1.74-2.14; P < .001) or no treatment (OR, 1.46; 95% CI, 1.32-1.61; P < .001), and Hispanic patients were more likely to receive systemic therapy only (OR, 1.36; 95% CI, 1.13-1.64; P = .001) or no treatment (OR, 1.36; 95% CI, 1.14-1.60; P < .001). Between 2004 and 2014, patients without insurance or enrolled in Medicaid had 1.83-fold greater person-years of life lost compared with patients with private insurance (area under the curve, 77 600 vs 42 300 person-years of life lost). Conclusions and Relevance: In this study, receipt of NDT was associated with insurance status and race/ethnicity. While treatment decisions should be individualized for every patient, younger men with high-risk prostate cancer and minimal comorbidities should be encouraged to receive definitive local therapy regardless of other factors. These data suggest that significant barriers to life-extending treatment options for patients with prostate cancer remain.

Predictors of urinary toxicity with MRI-assisted radiosurgery for low-dose-rate prostate brachytherapy.

PURPOSE: MRI-assisted radiosurgery (MARS) is a modern technique for prostate brachytherapy that provides superior soft tissue contrast. The purpose of this analysis was to evaluate treatment planning factors associated with urinary toxicity, particularly damage to the membranous urethra (MUL) and external urethral sphincter (EUS), after MARS. MATERIAL AND METHODS: We retrospectively reviewed 227 patients treated with MARS. Comparisons were made between several factors including preimplantation length of the MUL and EUS dosimetric characteristics after implantation with longitudinal changes in American Urological Association (AUA) urinary symptom score. RESULTS: Rates of grade 3 urinary incontinence and obstructive urinary symptoms were 4% and 2%. A piecewise mixed univariate model revealed that MUL and V200, V150, V125, and D5 to the EUS were all associated with increased rates of urinary toxicity over time. On univariate logistic regression, MUL >14.2 mm (odds ratio [OR] 2.03 per cm3, 95% confidence interval [CI] 1.10-3.77, p = 0.025), V125 to the EUS (OR 3.21 cm3, 95% CI 1.18-8.71, p = 0.022), and use of the I-125 isotope (OR 3.45, 95% CI 1.55-7.70, p = 0.001) were associated with subacute urinary toxicity (i.e., that occurring at 4-8 months). Optimal dose-constraint limits to the EUS were determined to be V200 < 0.04 cm3 (p = 0.002), V150 < 0.12 cm3 (p = 0.041), V125 < 0.45 cm3 (p = 0.033), D30 < 160 Gy (p = 0.004), and D5 < 218 Gy (p = 0.016). CONCLUSIONS: MARS brachytherapy provides detailed anatomic information for treatment planning, implantation, and quality assurance. Overall rates of urinary toxicity are low; however, several dosimetric variables associated with the EUS were found to correlate with urinary toxicity.

Correction: Epigenetic loss of AOX1 expression via EZH2 leads to metabolic deregulations and promotes bladder cancer progression.

After publication of this Article, the Authors noticed errors in some of the Figures. In Figures 2e, 2f-g, 4a, 4j, 5a and 6b, unmatched ß-actin was inadvertently used as loading control for the immunoblots. These have been corrected using repeat data from a similar set of samples and the revised Figures containing matched ß-actin and their respective quantification data are included below. In Figure 7a, the same image was inadvertently used to represent tumors 3 and 5 in the control group. This error has been corrected using original images of tumors 3 and 5 in the control group. Additional corrections have been made in the Article and Figure legends to enhance the clarity of the description. NAD was replaced by NADP. NAD/NADP was replaced by NADP/NADPH. The description of the antibody source and dilution for the antigens PFKFB4 (Abcam, 1:1000), G6PD, and HK1 (Cell Signaling, 1:1,000) have been included in the Methods section for Western Blot. The legend for Figure 4e and 4j has been updated. The HTML and PDF versions of this Article have been corrected. The scientific conclusions of this paper have not been affected.

Epigenetic loss of AOX1 expression via EZH2 leads to metabolic deregulations and promotes bladder cancer progression.

Advanced Bladder Cancer (BLCA) remains a clinical challenge that lacks effective therapeutic measures. Here, we show that distinct, stage-wise metabolic alterations in BLCA are associated with the loss of function of aldehyde oxidase (AOX1). AOX1 associated metabolites have a high predictive value for advanced BLCA and our findings demonstrate that AOX1 is epigenetically silenced during BLCA progression by the methyltransferase activity of EZH2. Knockdown (KD) of AOX1 in normal bladder epithelial cells re-wires the tryptophan-kynurenine pathway resulting in elevated NADP levels which may increase metabolic flux through the pentose phosphate (PPP) pathway, enabling increased nucleotide synthesis, and promoting cell invasion. Inhibition of NADP synthesis rescues the metabolic effects of AOX1 KD. Ectopic AOX1 expression decreases NADP production, PPP flux and nucleotide synthesis, while decreasing invasion in cell line models and suppressing growth in tumor xenografts. Further gain and loss of AOX1 confirm the EZH2-dependent activation, metabolic deregulation, and tumor growth in BLCA. Our findings highlight the therapeutic potential of AOX1 and provide a basis for the development of prognostic markers for advanced BLCA.

Nuclear receptor coregulator SNP discovery and impact on breast cancer risk.

BACKGROUND: Coregulator proteins are "master regulators", directing transcriptional and posttranscriptional regulation of many target genes, and are critical in many normal physiological processes, but also in hormone driven diseases, such as breast cancer. Little is known on how genetic changes in these genes impact disease development and progression. Thus, we set out to identify novel single nucleotide polymorphisms (SNPs) within SRC-1 (NCoA1), SRC-3 (NCoA3, AIB1), NCoR (NCoR1), and SMRT (NCoR2), and test the most promising SNPs for associations with breast cancer risk. METHODS: The identification of novel SNPs was accomplished by sequencing the coding regions of these genes in 96 apparently normal individuals (48 Caucasian Americans, 48 African Americans). To assess their association with breast cancer risk, five SNPs were genotyped in 1218 familial BRCA1/2-mutation negative breast cancer cases and 1509 controls (rs1804645, rs6094752, rs2230782, rs2076546, rs2229840). RESULTS: Through our resequencing effort, we identified 74 novel SNPs (30 in NCoR, 32 in SMRT, 10 in SRC-3, and 2 in SRC-1). Of these, 8 were found with minor allele frequency (MAF) >5% illustrating the large amount of genetic diversity yet to be discovered. The previously shown protective effect of rs2230782 in SRC-3 was strengthened (OR = 0.45 [0.21-0.98], p = 0.04). No significant associations were found with the other SNPs genotyped. CONCLUSIONS: This data illustrates the importance of coregulators, especially SRC-3, in breast cancer development and suggests that more focused studies, including functional analyses, should be conducted.

Dose Escalation for Prostate Adenocarcinoma: A Long-Term Update on the Outcomes of a Phase 3, Single Institution Randomized Clinical Trial.

PURPOSE: To determine the long-term outcomes for prostate adenocarcinoma when escalating radiation dose from 70 Gy to 78 Gy. METHODS AND MATERIALS: Between 1993 and 1998, 301 patients with biopsy-proven clinical stage T1b-T3 prostate adenocarcinoma, any prostate-specific antigen level, and any Gleason score were randomized to 70 Gy in 35 fractions versus 78 Gy in 39 fractions of photon radiation therapy using a 4-field box technique without hormone deprivation therapy. The primary outcome was powered to detect a 15% difference in biochemical or clinical failure. Secondary outcomes included survival, prostate cancer mortality, biochemical failure, local failure, nodal failure, distant failure, and secondary malignancy rates. RESULTS: With a median follow-up of 14.3 years, the cumulative incidence of 15-year biochemical or clinical failure was 18.9% versus 12.0% in the 70 Gy versus 78 Gy arms, respectively (subhazard ratio [sHR], 0.61; 95% confidence interval [CI], 0.38-0.98; Fine-Gray P = .042). The 15-year cumulative incidence of distant metastasis was 3.4% versus 1.1%, respectively (sHR, 0.33; 95% CI, 0.13-0.82; Fine-Gray P = .018). The 15-year cumulative incidence of prostate cancer-specific mortality was 6.2% versus 3.2%, respectively, (sHR, 0.52; 95% CI, 0.27-0.98; Fine-Gray P = .045). There were no differences in overall survival (HR, 1.10; 95% CI, 0.84-1.45; log rank P = .469) or other-cause survival (sHR, 1.33; 95% CI, 0.99-1.79; Fine-Gray P = .061). Salvage therapy was more common in the 70 Gy arm, at 38.7% versus 21.9% in the 78 Gy arm (P = .002). There was a 2.3% secondary solid malignancy rate (1 bladder, 6 rectal) within the radiation treatment field, which was not significantly different between treatment arms. CONCLUSIONS: Dose escalation by 8 Gy (78 Gy vs 70 Gy) provided a sustained improvement in biochemical and clinical failure, which translated into lower salvage rates and improved prostate cancer-specific mortality, but not overall survival. Long-term follow-up demonstrated a low incidence of potential solid tumor secondary malignancies.

Androgen receptor-modulatory microRNAs provide insight into therapy resistance and therapeutic targets in advanced prostate cancer.

Androgen receptor (AR) signalling is a key prostate cancer (PC) driver, even in advanced 'castrate-resistant' disease (CRPC). To systematically identify microRNAs (miRs) modulating AR activity in lethal disease, hormone-responsive and -resistant PC cells expressing a luciferase-based AR reporter were transfected with a miR inhibitor library; 78 inhibitors significantly altered AR activity. Upon validation, miR-346, miR-361-3p and miR-197 inhibitors markedly reduced AR transcriptional activity, mRNA and protein levels, increased apoptosis, reduced proliferation, repressed EMT, and inhibited PC migration and invasion, demonstrating additive effects with AR inhibition. Corresponding miRs increased AR activity through a novel and anti-dogmatic mechanism of direct association with AR 6.9 kb 3'UTR and transcript stabilisation. In addition, miR-346 and miR-361-3p modulation altered levels of constitutively active AR variants, and inhibited variant-driven PC cell proliferation, so may contribute to persistent AR signalling in CRPC in the absence of circulating androgens. Pathway analysis of AGO-PAR-CLIP-identified miR targets revealed roles in DNA replication and repair, cell cycle, signal transduction and immune function. Silencing these targets, including tumour suppressors ARHGDIA and TAGLN2, phenocopied miR effects, demonstrating physiological relevance. MiR-346 additionally upregulated the oncogene, YWHAZ, which correlated with grade, biochemical relapse and metastasis in patients. These AR-modulatory miRs and targets correlated with AR activity in patient biopsies, and were elevated in response to long-term enzalutamide treatment of patient-derived CRPC xenografts. In summary, we identified miRs that modulate AR activity in PC and CRPC, via novel mechanisms, and may represent novel PC therapeutic targets.

Mitochondrial pyruvate import is a metabolic vulnerability in androgen receptor-driven prostate cancer.

Specific metabolic underpinnings of androgen receptor (AR)-driven growth in prostate adenocarcinoma (PCa) are largely undefined, hindering the development of strategies to leverage the metabolic dependencies of this disease when hormonal manipulations fail. Here we show that the mitochondrial pyruvate carrier (MPC), a critical metabolic conduit linking cytosolic and mitochondrial metabolism, is transcriptionally regulated by AR. Experimental MPC inhibition restricts proliferation and metabolic outputs of the citric acid cycle (TCA) including lipogenesis and oxidative phosphorylation in AR-driven PCa models. Mechanistically, metabolic disruption resulting from MPC inhibition activates the eIF2α/ATF4 integrated stress response (ISR). ISR signaling prevents cell cycle progression while coordinating salvage efforts, chiefly enhanced glutamine assimilation into the TCA, to regain metabolic homeostasis. We confirm that MPC function is operant in PCa tumors in-vivo using isotopomeric metabolic flux analysis. In turn, we apply a clinically viable small molecule targeting the MPC, MSDC0160, to pre-clinical PCa models and find that MPC inhibition suppresses tumor growth in hormone-responsive and castrate-resistant conditions. Collectively, our findings characterize the MPC as a tractable therapeutic target in AR-driven prostate tumors.

Four-dimensional computed tomography-based treatment planning for intensity-modulated radiation therapy and proton therapy for distal esophageal cancer.

PURPOSE: To compare three-dimensional (3D) and four-dimensional (4D) computed tomography (CT)-based treatment plans for proton therapy or intensity-modulated radiation therapy (IMRT) for esophageal cancer in terms of doses to the lung, heart, and spinal cord and variations in target coverage and normal tissue sparing. METHODS AND MATERIALS: The IMRT and proton plans for 15 patients with distal esophageal cancer were designed from the 3D average CT scans and then recalculated on 10 4D CT data sets. Dosimetric data were compared for tumor coverage and normal tissue sparing. RESULTS: Compared with IMRT, median lung volumes exposed to 5, 10, and 20 Gy and mean lung dose were reduced by 35.6%, 20.5%, 5.8%, and 5.1 Gy for a two-beam proton plan and by 17.4%, 8.4%, 5%, and 2.9 Gy for a three-beam proton plan. The greater lung sparing in the two-beam proton plan was achieved at the expense of less conformity to the target (conformity index [CI], 1.99) and greater irradiation of the heart (heart-V40, 41.8%) compared with the IMRT plan(CI, 1.55, heart-V40, 35.7%) or the three-beam proton plan (CI, 1.46, heart-V40, 27.7%). Target coverage differed by more than 2% between the 3D and 4D plans for patients with substantial diaphragm motion in the three-beam proton and IMRT plans. The difference in spinal cord maximum dose between 3D and 4D plans could exceed 5 Gy for the proton plans partly owing to variations in stomach gas filling. CONCLUSIONS: Proton therapy provided significantly better sparing of lung than did IMRT. Diaphragm motion and stomach gas-filling must be considered in evaluating target coverage and cord doses.

Treatment of recurrent vaginal melanoma with external beam radiation therapy and palladium-103 brachytherapy.

BACKGROUND: Mucosal melanoma of the female genital tract that recurs locally after definitive surgery presents difficult challenges for salvage therapy. METHODS AND MATERIALS: A 71-year-old female was diagnosed with a 4.5-cm x 4.1-cm x 2.8-cm vaginal recurrence of genital tract mucosal melanoma after definitive vulvectomy, distal vaginectomy, and distal urethrectomy. She refused surgery and underwent combination external beam radiation therapy (46 Gy) and an ultrasound-guided palladium-103 brachytherapy implant (100 Gy). RESULTS: The patient experienced complete resolution of the gross tumor and was asymptomatic with a sustained response for over a year before developing metastatic disease. CONCLUSIONS: Mucosal melanoma of the female genital tract is an aggressive and often fatal disease. Radical surgical excision is an option for some patients but may require pelvic exenteration and is rarely curative. In selected cases, high-dose conformal radiation therapy delivered by a combination of external beam radiation therapy and interstitial brachytherapy may be an excellent alternative, achieving local control without loss of organ function.

Randomized Trial of Hypofractionated, Dose-Escalated, Intensity-Modulated Radiation Therapy (IMRT) Versus Conventionally Fractionated IMRT for Localized Prostate Cancer.

PURPOSE: Hypofractionated radiotherapy delivers larger daily doses of radiation and may increase the biologically effective dose delivered to the prostate. We conducted a randomized trial testing the hypothesis that dose-escalated, moderately hypofractionated intensity-modulated radiation therapy (HIMRT) improves prostate cancer control compared with conventionally fractionated IMRT (CIMRT) for men with localized prostate cancer. PATIENTS AND METHODS: Men were randomly assigned to 75.6 Gy in 1.8-Gy fractions delivered over 8.4 weeks (CIMRT) or 72 Gy in 2.4 Gy fractions delivered over 6 weeks (HIMRT, biologically equivalent to 85 Gy in 1.8-Gy fractions assuming prostate cancer α-to-ß ratio of 1.5). Failure was defined as prostate-specific antigen (PSA) failure (nadir plus 2 ng/mL) or initiation of salvage therapy. Modified Radiation Therapy Oncology Group criteria were used to grade late (≥ 90 days after completion of radiotherapy) GI and genitourinary toxicity. RESULTS: Most of the 206 men (72%) had cT1, Gleason score 6 or 7 (99%), and PSA level ≤ 10 ng/mL (90%) disease. Androgen deprivation therapy was received by 24%. With a median follow-up of 8.5 years, men treated with HIMRT experienced fewer treatment failures (n = 10) than men treated with CIMRT (n = 21; P = .036). The 8-year failure rate was 10.7% (95% CI, 5.8% to 19.1%) with HIMRT and 15.4% (95% CI, 9.1% to 25.4%) with CIMRT. There was no difference in overall survival ( P = .39). There was a nonsignificant increase in late grade 2 or 3 GI toxicity with HIMRT (8-year 5.0% v 12.6%; P = .08). However, GI toxicity was only 8.6% when rectal volume receiving 65 Gy of HIMRT was ≤ 15%. Late genitourinary toxicity was similar ( P = .84). There was no grade 4 toxicity. CONCLUSION: The results of this randomized trial demonstrate superior cancer control for men with localized prostate cancer who receive dose-escalated moderately hypofractionation radiotherapy while shortening treatment duration.