African American Prostate Cancer Displays Quantitatively Distinct Vitamin D Receptor Cistrome-transcriptome Relationships Regulated by BAZ1A.

African American (AA) prostate cancer associates with vitamin D3 deficiency, but vitamin D receptor (VDR) genomic actions have not been investigated in this context. We undertook VDR proteogenomic analyses in European American (EA) and AA prostate cell lines and four clinical cohorts. Rapid immunoprecipitation mass spectrometry of endogenous protein (RIME) analyses revealed that nonmalignant AA RC43N prostate cells displayed the greatest dynamic protein content in the VDR complex. Likewise, in AA cells, Assay for Transposase-Accessible Chromatin using sequencing established greater 1α,25(OH)2D3-regulated chromatin accessibility, chromatin immunoprecipitation sequencing revealed significant enhancer-enriched VDR cistrome, and RNA sequencing identified the largest 1α,25(OH)2D3-dependent transcriptome. These VDR functions were significantly corrupted in the isogenic AA RC43T prostate cancer cells, and significantly distinct from EA cell models. We identified reduced expression of the chromatin remodeler, BAZ1A, in three AA prostate cancer cohorts as well as RC43T compared with RC43N. Restored BAZ1A expression significantly increased 1α,25(OH)2D3-regulated VDR-dependent gene expression in RC43T, but not HPr1AR or LNCaP cells. The clinical impact of VDR cistrome-transcriptome relationships were tested in three different clinical prostate cancer cohorts. Strikingly, only in AA patients with prostate cancer, the genes bound by VDR and/or associated with 1α,25(OH)2D3-dependent open chromatin (i) predicted progression from high-grade prostatic intraepithelial neoplasia to prostate cancer; (ii) responded to vitamin D3 supplementation in prostate cancer tumors; (iii) differentially responded to 25(OH)D3 serum levels. Finally, partial correlation analyses established that BAZ1A and components of the VDR complex identified by RIME significantly strengthened the correlation between VDR and target genes in AA prostate cancer only. Therefore, VDR transcriptional control is most potent in AA prostate cells and distorted through a BAZ1A-dependent control of VDR function. Significance: Our study identified that genomic ancestry drives the VDR complex composition, genomic distribution, and transcriptional function, and is disrupted by BAZ1A and illustrates a novel driver for AA prostate cancer.

Benefit of adjuvant chemotherapy in node-negative T1a versus T1b and T1c triple-negative breast cancer.

PURPOSE: National comprehensive cancer network guidelines recommend delivery of adjuvant chemotherapy in node-negative triple-negative breast cancer (TNBC) if the tumor is > 1 cm and consideration of adjuvant chemotherapy for T1b but not T1a disease. These recommendations are based upon sparse data on the role of adjuvant chemotherapy in T1a and T1b node-negative TNBC. Our objective was to clarify the benefits of chemotherapy for patients with T1N0 TNBC, stratified by tumor size. METHODS: We performed a retrospective analysis of survival outcomes of TNBC patients at two academic institutions in the United States from 1999 to 2018. Primary tumor size, histology, and nodal status were based upon surgical pathology. The Kaplan-Meier plot and 5-year unadjusted survival probability were evaluated. RESULTS: Among 282 T1N0 TNBC cases, the status of adjuvant chemotherapy was known for 258. Mean follow-up was 5.3 years. Adjuvant chemotherapy was delivered to 30.5% of T1a, 64.7% T1b, and 83.9% T1c (p < 0.0001). On multivariable analysis, factors associated with delivery of adjuvant chemotherapy were tumor size and grade 3 disease. Improved overall survival was associated with use of chemotherapy in patients with T1c disease (93.2% vs. 75.2% p = 0.008) but not T1a (100% vs. 100% p = 0.3778) or T1b (100% vs. 95.8% p = 0.2362) disease. CONCLUSION: Our data support current guidelines indicating benefit from adjuvant chemotherapy in node-negative TNBC associated with T1c tumors but excellent outcomes were observed in the cases of T1a and T1b disease, regardless of whether adjuvant chemotherapy was delivered.

Expedited and Comprehensive Management of Low-Risk TIA Patients in the Emergency Department is Safe and Less Costly.

OBJECTIVES: Transient ischemic attack (TIA) can be a warning sign of an impending stroke. The objective of our study is to assess the feasibility, safety, and cost savings of a comprehensive TIA protocol in the emergency room for low-risk TIA patients. MATERIALS AND METHODS: This is a retrospective, single-center cohort study performed at an academic comprehensive stroke center. We implemented an emergency department-based TIA protocol pathway for low-risk TIA patients (defined as ABCD2 score < 4 and without significant vessel stenosis) who were able to undergo vascular imaging and a brain MRI in the emergency room. Patients were set up with rapid outpatient follow-up in our stroke clinic and scheduled for an outpatient echocardiogram, if indicated. We compared this cohort to TIA patients admitted prior to the implementation of the TIA protocol who would have qualified. Outcomes of interest included length of stay, hospital cost, radiographic and echocardiogram findings, recurrent neurovascular events within 30 days, and final diagnosis. RESULTS: A total of 138 patients were assessed (65 patients in the pre-pathway cohort, 73 in the expedited, post-TIA pathway implementation cohort). Average time from MRI order to MRI end was 6.4 h compared to 2.3 h in the pre- and post-pathway cohorts, respectively (p < 0.0001). The average length of stay for the pre-pathway group was 28.8 h in the pre-pathway cohort compared to 7.7 h in the post-pathway cohort (p < 0.0001). There were no differences in neuroimaging or echocardiographic findings. There were no differences in the 30 days re-presentation for stroke or TIA or mortality between the two groups. The direct cost per TIA admission was $2,944.50 compared to $1,610.50 for TIA patients triaged through the pathway at our institution. CONCLUSIONS: This study demonstrates the feasibility, safety, and cost-savings of a comprehensive, emergency department-based TIA protocol. Further study is needed to confirm overall benefit of an expedited approach to TIA patient management and guide clinical practice recommendations.

Systems pharmacogenomics identifies novel targets and clinically actionable therapeutics for medulloblastoma.

BACKGROUND: Medulloblastoma (MB) is the most common malignant paediatric brain tumour and a leading cause of cancer-related mortality and morbidity. Existing treatment protocols are aggressive in nature resulting in significant neurological, intellectual and physical disabilities for the children undergoing treatment. Thus, there is an urgent need for improved, targeted therapies that minimize these harmful side effects. METHODS: We identified candidate drugs for MB using a network-based systems-pharmacogenomics approach: based on results from a functional genomics screen, we identified a network of interactions implicated in human MB growth regulation. We then integrated drugs and their known mechanisms of action, along with gene expression data from a large collection of medulloblastoma patients to identify drugs with potential to treat MB. RESULTS: Our analyses identified drugs targeting CDK4, CDK6 and AURKA as strong candidates for MB; all of these genes are well validated as drug targets in other tumour types. We also identified non-WNT MB as a novel indication for drugs targeting TUBB, CAD, SNRPA, SLC1A5, PTPRS, P4HB and CHEK2. Based upon these analyses, we subsequently demonstrated that one of these drugs, the new microtubule stabilizing agent, ixabepilone, blocked tumour growth in vivo in mice bearing patient-derived xenograft tumours of the Sonic Hedgehog and Group 3 subtype, providing the first demonstration of its efficacy in MB. CONCLUSIONS: Our findings confirm that this data-driven systems pharmacogenomics strategy is a powerful approach for the discovery and validation of novel therapeutic candidates relevant to MB treatment, and along with data validating ixabepilone in PDX models of the two most aggressive subtypes of medulloblastoma, we present the network analysis framework as a resource for the field.

Label-free ferrohydrodynamic cell separation of circulating tumor cells.

Circulating tumor cells (CTCs) have significant implications in both basic cancer research and clinical applications. To address the limited availability of viable CTCs for fundamental and clinical investigations, effective separation of extremely rare CTCs from blood is critical. Ferrohydrodynamic cell separation (FCS), a label-free method that conducted cell sorting based on cell size difference in biocompatible ferrofluids, has thus far not been able to enrich low-concentration CTCs from cancer patients' blood because of technical challenges associated with processing clinical samples. In this study, we demonstrated the development of a laminar-flow microfluidic FCS device that was capable of enriching rare CTCs from patients' blood in a biocompatible manner with a high throughput (6 mL h-1) and a high rate of recovery (92.9%). Systematic optimization of the FCS devices through a validated analytical model was performed to determine optimal magnetic field and its gradient, ferrofluid properties, and cell throughput that could process clinically relevant amount of blood. We first validated the capability of the FCS devices by successfully separating low-concentration (∼100 cells per mL) cancer cells using six cultured cell lines from undiluted white blood cells (WBCs), with an average 92.9% cancer cell recovery rate and an average 11.7% purity of separated cancer cells, at a throughput of 6 mL per hour. Specifically, at ∼100 cancer cells per mL spike ratio, the recovery rates of cancer cells were 92.3 ± 3.6% (H1299 lung cancer), 88.3 ± 5.5% (A549 lung cancer), 93.7 ± 5.5% (H3122 lung cancer), 95.3 ± 6.0% (PC-3 prostate cancer), 94.7 ± 4.0% (MCF-7 breast cancer), and 93.0 ± 5.3% (HCC1806 breast cancer), and the corresponding purities of separated cancer cells were 11.1 ± 1.2% (H1299 lung cancer), 10.1 ± 1.7% (A549 lung cancer), 12.1 ± 2.1% (H3122 lung cancer), 12.8 ± 1.6% (PC-3 prostate cancer), 11.9 ± 1.8% (MCF-7 breast cancer), and 12.2 ± 1.6% (HCC1806 breast cancer). Biocompatibility study on H1299 cell line and HCC1806 cell line showed that separated cancer cells had excellent short-term viability, normal proliferation and unaffected key biomarker expressions. We then demonstrated the enrichment of CTCs in blood samples obtained from two patients with newly diagnosed advanced non-small cell lung cancer (NSCLC). While still at its early stage of development, FCS could become a complementary tool for CTC separation for its high recovery rate and excellent biocompatibility, as well as its potential for further optimization and integration with other separation methods.

Chronically Increased Amino Acids Improve Insulin Secretion, Pancreatic Vascularity, and Islet Size in Growth-Restricted Fetal Sheep.

Placental insufficiency is associated with reduced supply of amino acids to the fetus and leads to intrauterine growth restriction (IUGR). IUGR fetuses are characterized by lower glucose-stimulated insulin secretion, smaller pancreatic islets with less ß-cells, and impaired pancreatic vascularity. To test whether supplemental amino acids infused into the IUGR fetus could improve these complications of IUGR we used acute (hours) and chronic (11 d) direct fetal amino acid infusions into a sheep model of placental insufficiency and IUGR near the end of gestation. IUGR fetuses had attenuated acute amino acid-stimulated insulin secretion compared with control fetuses. These results were confirmed in isolated IUGR pancreatic islets. After the chronic fetal amino acid infusion, fetal glucose-stimulated insulin secretion and islet size were restored to control values. These changes were associated with normalization of fetal pancreatic vascularity and higher fetal pancreatic vascular endothelial growth factor A protein concentrations. These results demonstrate that decreased fetal amino acid supply contributes to the pathogenesis of pancreatic islet defects in IUGR. Moreover, the results show that pancreatic islets in IUGR fetuses retain their ability to respond to increased amino acids near the end of gestation after chronic fetal growth restriction.

Screening for hepatitis C virus antiviral activity with a cell-based secreted alkaline phosphatase reporter replicon system.

We describe a phased screening system for discovery of compounds with antiviral activity against hepatitis C virus (HCV). The primary assay utilizes dicistronic subgenomic HCV replicons in which the upstream cistron was modified to express the human immunodeficiency virus (HIV) tat protein. When these replicons are stably transfected into Huh-7-derived cells that express secreted alkaline phosphatase (SEAP) under transcriptional control of the HIV long terminal repeat promoter, there is a strong correlation between intracellular HCV RNA abundance and the activity of SEAP secreted into the culture medium. Thus, active compounds are easily identified by direct enzymatic quantification of SEAP in the medium without post-assay processing. Compounds that reduce SEAP activity without causing cellular toxicity are next evaluated in a second Huh-7-derived cell line constitutively expressing SEAP under control of the tat-HIV promoter axis, independent of HCV RNA replication. This specificity control identifies compounds that cause reductions in SEAP that are unrelated to suppression of HCV RNA replication. Compounds showing HCV-specific activity in primary assays are next evaluated by real-time RT-PCR to directly quantify reductions in HCV RNA. We have found excellent agreement between the SEAP and RT-PCR assays. This phased system provides an efficient and cost-effective screen for compounds with antiviral activity against HCV.