Interplay of gut microbiota and host epithelial mitochondrial dysfunction is necessary for the development of spontaneous intestinal inflammation in mice.

BACKGROUND: Intestinal epithelial cell (IEC) mitochondrial dysfunction involvement in inflammatory bowel diseases (IBD), including Crohn's disease affecting the small intestine, is emerging in recent studies. As the interface between the self and the gut microbiota, IECs serve as hubs of bidirectional cross-talk between host and luminal microbiota. However, the role of mitochondrial-microbiota interaction in the ileum is largely unexplored. Prohibitin 1 (PHB1), a chaperone protein of the inner mitochondrial membrane required for optimal electron transport chain function, is decreased during IBD. We previously demonstrated that mice deficient in PHB1 specifically in IECs (Phb1i∆IEC) exhibited mitochondrial impairment, Paneth cell defects, gut microbiota dysbiosis, and spontaneous inflammation in the ileum (ileitis). Mice deficient in PHB1 in Paneth cells (epithelial secretory cells of the small intestine; Phb1∆PC) also exhibited mitochondrial impairment, Paneth cell defects, and spontaneous ileitis. Here, we determined whether this phenotype is driven by Phb1 deficiency-associated ileal microbiota alterations or direct effects of loss of PHB1 in host IECs. RESULTS: Depletion of gut microbiota by broad-spectrum antibiotic treatment in Phb1∆PC or Phb1i∆IEC mice revealed a necessary role of microbiota to cause ileitis. Using germ-free mice colonized with ileal microbiota from Phb1-deficient mice, we show that this microbiota could not independently induce ileitis without host mitochondrial dysfunction. The luminal microbiota phenotype of Phb1i∆IEC mice included a loss of the short-chain fatty acid butyrate. Supplementation of butyrate in Phb1-deficient mice ameliorated Paneth cell abnormalities and ileitis. Phb1-deficient ileal enteroid models suggest deleterious epithelial-intrinsic responses to ileal microbiota that were protected by butyrate. CONCLUSIONS: These results suggest a mutual and essential reinforcing interplay of gut microbiota and host IEC, including Paneth cell, mitochondrial health in influencing ileitis. Restoration of butyrate is a potential therapeutic option in Crohn's disease patients harboring epithelial cell mitochondrial dysfunction. Video Abstract.

Sleep related rhythmic movement disorder: phenotypic characteristics and treatment response in a paediatric cohort.

OBJECTIVE: To describe phenotypic, polysomnographic characteristics, impact, and treatment response in children with sleep related rhythmic movement disorder (SR-RMD). BACKGROUND: There is limited research on SR-RMD. We have developed a systematic clinical evaluation of children with SR-RMD to improve understanding and treatment. METHODS: A retrospective chart review of 66 children at a UK tertiary hospital. Baseline assessment included validated screening questionnaires to study autism spectrum characteristics, general behaviour and sensory profile. A standardised questionnaire assessed impact on sleep quality and daytime wellbeing of child and family. Polysomnography data were collated. RESULTS: Children were aged 0.9-16.3 years (78.8% male). 51.5% had a neurodevelopmental disorder, most commonly autism spectrum disorder. High rates of behavioural disturbance and sensory processing differences were reported, not confined to children with neurodevelopmental disorders. Parents reported concerns about risk of injury, loss of sleep and persistence into adulthood. Daytime wellbeing was affected in 72% of children and 75% of other family members. Only 31/48 children demonstrated rhythmic movements during video-polysomnography, occupying on average 6.1% of time in bed. Most clusters occurred in the settling period but also arose from N1, N2 and REM sleep and wake after sleep onset. Melatonin was prescribed to 52 children, all but one were extended-release preparations. 24/27 children with available data were reported to improve with melatonin. CONCLUSIONS: SR-RMD places a significant burden on child and family wellbeing. Our novel findings of sensory processing differences in this population and parent reported therapeutic response to extended-release melatonin offer potential avenues for future research.

A defect in mitochondrial fatty acid synthesis impairs iron metabolism and causes elevated ceramide levels.

In most eukaryotic cells, fatty acid synthesis (FAS) occurs in the cytoplasm and in mitochondria. However, the relative contribution of mitochondrial FAS (mtFAS) to the cellular lipidome is not well defined. Here we show that loss of function of Drosophila mitochondrial enoyl coenzyme A reductase (Mecr), which is the enzyme required for the last step of mtFAS, causes lethality, while neuronal loss of Mecr leads to progressive neurodegeneration. We observe a defect in Fe-S cluster biogenesis and increased iron levels in flies lacking mecr, leading to elevated ceramide levels. Reducing the levels of either iron or ceramide suppresses the neurodegenerative phenotypes, indicating an interplay between ceramide and iron metabolism. Mutations in human MECR cause pediatric-onset neurodegeneration, and we show that human-derived fibroblasts display similar elevated ceramide levels and impaired iron homeostasis. In summary, this study identifies a role of mecr/MECR in ceramide and iron metabolism, providing a mechanistic link between mtFAS and neurodegeneration.

Screening of GPCR drugs for repurposing in breast cancer.

Drug repurposing can overcome both substantial costs and the lengthy process of new drug discovery and development in cancer treatment. Some Food and Drug Administration (FDA)-approved drugs have been found to have the potential to be repurposed as anti-cancer drugs. However, the progress is slow due to only a handful of strategies employed to identify drugs with repurposing potential. In this study, we evaluated GPCR-targeting drugs by high throughput screening (HTS) for their repurposing potential in triple-negative breast cancer (TNBC) and drug-resistant human epidermal growth factor receptor-2-positive (HER2+) breast cancer (BC), due to the dire need to discover novel targets and drugs in these subtypes. We assessed the efficacy and potency of drugs/compounds targeting different GPCRs for the growth rate inhibition in the following models: two TNBC cell lines (MDA-MB-231 and MDA-MB-468) and two HER2+ BC cell lines (BT474 and SKBR3), sensitive or resistant to lapatinib + trastuzumab, an effective combination of HER2-targeting therapies. We identified six drugs/compounds as potential hits, of which 4 were FDA-approved drugs. We focused on ß-adrenergic receptor-targeting nebivolol as a candidate, primarily because of the potential role of these receptors in BC and its excellent long-term safety profile. The effects of nebivolol were validated in an independent assay in all the cell line models. The effects of nebivolol were independent of its activation of ß3 receptors and nitric oxide production. Nebivolol reduced invasion and migration potentials which also suggests its inhibitory role in metastasis. Analysis of the Surveillance, Epidemiology and End Results (SEER)-Medicare dataset found numerically but not statistically significant reduced risk of all-cause mortality in the nebivolol group. In-depth future analyses, including detailed in vivo studies and real-world data analysis with more patients, are needed to further investigate the potential of nebivolol as a repurposed therapy for BC.

Targeting aberrant replication and DNA repair events for treating breast cancers.

The major limitations of DNA-targeting chemotherapy drugs include life-threatening toxicity, acquired resistance and occurrence of secondary cancers. Here, we report a small molecule, Carbazole Blue (CB), that binds to DNA and inhibits cancer growth and metastasis by targeting DNA-related processes that tumor cells use but not the normal cells. We show that CB inhibits the expression of pro-tumorigenic genes that promote unchecked replication and aberrant DNA repair that cancer cells get addicted to survive. In contrast to chemotherapy drugs, systemic delivery of CB suppressed breast cancer growth and metastasis with no toxicity in pre-clinical mouse models. Using PDX and ex vivo explants from estrogen receptor (ER) positive, ER mutant and TNBC patients, we further demonstrated that CB effectively blocks therapy-sensitive and therapy-resistant breast cancer growth without affecting normal breast tissue. Our data provide a strong rationale to develop CB as a viable therapeutic for treating breast cancers.

Risk factors associated to intestinal anastomotic leakage in elective surgery.

BACKGROUND: The intestinal anastomotic leakage is the most feared surgical complication of a digestive surgery and is associated with a significant increase of morbidity, mortality and hospital stay. OBJECTIVE: Analyze the risk factors to the intestinal anastomotic leakage in elective surgery. METHOD: Observational and retrospective study in which we include patients with intestinal anastomosis, in elective surgery at the second level hospital from January 2007 to January 2017. RESULTS: 64 patients were included in the study, in which 7 presented anastomotic leakage. The statistically significant risk factors associated with anastomotic leakage were, cocaine use (p = 0.030), neoplasia as a primary pathology (p = 0.008), neoadjuvant treatment for neoplasia (p = 0.003), and end-to-end anastomosis (p = 0.037). Patients with a leakage had a longer hospital stay and a mortality of 14.3%. CONCLUSIONS: The risk factors associated with the presence of anastomotic leakage found in this study are consistent with the reported worldwide literature. However, in our results, it is worth highlighting the use of cocaine as a risk factor, with statistical significance.

ANTECEDENTES: La fuga de una anastomosis intestinal es la complicación quirúrgica más temida de la cirugía digestiva y se asocia con un aumento significativo de la morbimortalidad y de la estancia hospitalaria. OBJETIVO: Analizar los factores de riesgo asociados a la fuga de anastomosis intestinal en cirugía electiva. MÉTODO: Estudio observacional y retrospectivo en el que se recabaron los expedientes de los pacientes operados de anastomosis intestinal en forma electiva en un hospital de segundo nivel de enero de 2007 a enero de 2017. RESULTADOS: Se incluyeron 64 pacientes, de los cuales siete presentaron fuga de la anastomosis. Los factores de riesgo asociados a fuga anastomótica estadísticamente significativos fueron consumo de cocaína (p = 0.030), neoplasia como patología primaria (p = 0.008), tratamiento con neoadyuvantes para neoplasia (p = 0.003) y anastomosis término-terminal (p = 0.037). Los pacientes con fuga tuvieron una estancia intrahospitalaria más prolongada y una mortalidad del 14.3%. CONCLUSIONES: Los factores de riesgo asociados con la presencia de fuga anastomótica encontrados en este estudio son consistentes con los reportados en la literatura mundial. Sin embargo, en nuestros resultados cabe destacar el uso de cocaína como factor de riesgo, con significancia estadística.

Targeting Mitochondrial Damage as a Therapeutic for Ileal Crohn's Disease.

Paneth cell defects in Crohn's disease (CD) patients (called the Type I phenotype) are associated with worse clinical outcomes. Recent studies have implicated mitochondrial dysfunction in Paneth cells as a mediator of ileitis in mice. We hypothesized that CD Paneth cells exhibit impaired mitochondrial health and that mitochondrial-targeted therapeutics may provide a novel strategy for ileal CD. Terminal ileal mucosal biopsies from adult CD and non-IBD patients were characterized for Paneth cell phenotyping and mitochondrial damage. To demonstrate the response of mitochondrial-targeted therapeutics in CD, biopsies were treated with vehicle or Mito-Tempo, a mitochondrial-targeted antioxidant, and RNA transcriptome was analyzed. During active CD inflammation, the epithelium exhibited mitochondrial damage evident in Paneth cells, goblet cells, and enterocytes. Independent of inflammation, Paneth cells in Type I CD patients exhibited mitochondrial damage. Mito-Tempo normalized the expression of interleukin (IL)-17/IL-23, lipid metabolism, and apoptotic gene signatures in CD patients to non-IBD levels. When stratified by Paneth cell phenotype, the global tissue response to Mito-Tempo in Type I patients was associated with innate immune, lipid metabolism, and G protein-coupled receptor (GPCR) gene signatures. Targeting impaired mitochondria as an underlying contributor to inflammation provides a novel treatment approach for CD.

Ataxia-telangiectasia mutated interacts with Parkin and induces mitophagy independent of kinase activity. Evidence from mantle cell lymphoma.

Ataxia telangiectasia mutated (ATM), a critical DNA damage sensor with protein kinase activity,is frequently altered in human cancers including mantle cell lymphoma (MCL). Loss of ATM protein is linked to accumulation of nonfunctional mitochondria and defective mitophagy, in both murine thymocytes and in A-T cells. However, the mechanistic role of ATM kinase in cancer cell mitophagy is unknown. Here, we provide evidence that FCCP-induced mitophagy in MCL and other cancer cell lines is dependent on ATM but independent of its kinase function. While Granta-519 MCL cells possess single copy and kinase dead ATM and are resistant to FCCP-induced mitophagy, both Jeko-1 and Mino cells are ATM proficient and induce mitophagy. Stable knockdown of ATM in Jeko-1 and Mino cells conferred resistance to mitophagy and was associated with reduced ATP production, oxygen consumption, and increased mROS. ATM interacts with the E3 ubiquitin ligase Parkin in a kinase-independent manner. Knockdown of ATM in HeLa cells resulted in proteasomal degradation of GFP-Parkin which was rescued by the proteasome inhibitor, MG132 suggesting that ATM-Parkin interaction is important for Parkin stability. Neither loss of ATM kinase activity in primary B cell lymphomas nor inhibition of ATM kinase in MCL, A-T and HeLa cell lines mitigated FCCP or CCCP-induced mitophagy suggesting that ATM kinase activity is dispensable for mitophagy. Malignant B-cell lymphomas without detectable ATM, Parkin, Pink1, and Parkin-Ub ser65 phosphorylation were resistant to mitophagy, providing the first molecular evidence of ATM's role in mitophagy in MCL and other B-cell lymphomas.

Síndrome congénito asociado a virus Zika

La infección por el virus Zika (ZIKV) inicialmente descrita como una enfermedad febril leve, hoy se conoce por estar asociada a malformaciones congénitas, destacando la microcefalia. En Venezuela son poco los datos registrados, por lo que se plantea la realización de un estudio para describir el comportamiento de la enfermedad congénita en la población venezolana. Metodología: Se realizó un estudio prospectivo, observacional, se incluyeron todos los niños que acudieron a la consulta de Infectología Pediátrica del Hospital Universitario de Caracas entre agosto de 2016 y marzo de 2018 con diagnóstico de microcefalia y/o aquellos con exposición sospechada o confirmada al virus Zika durante la gestación, siendo evaluados mediante examen físico y estudios paraclínicos. Todos los pacientes fueron evaluados por equipo multidisciplinario. Resultados: Se incluyeron 28 pacientes, prevaleciendo el sexo femenino con 53,6 %, el 60,7 % de los pacientes presentaron microcefalia. Se observaron malformaciones esqueléticas: artrogriposis, pie equinovaro, pie valgo, afecciones oculares: endotropía, catarata congénita, leucocoria bilateral, microftalmia. En el 28,6 % de pacientes no se evidenciaron malformaciones. Se observaron casos confirmados para Zika, con microcefalia y TAC de cráneo con ventriculomegalia, así como pacientes con circunferencia cefálica (CC) normal y estudios de imagen sin alteraciones. Se reportan 2 casos con CC normal al nacimiento y progresión a microcefalia en consultas sucesivas. Conclusiones: El virus Zika se encuentra asociado con síndrome genético caracterizado por microcefalia, malformaciones musculoesqueléticas y oftalmológicas. La microcefalia en la infección por virus Zika se puede desarrollar en el período postnatal.

The Zika virus infection (ZIKV) initially described as a mild febrile disease, is now known to be associated with congenital malformations, highlighting microcephaly. In Venezuela there is little data recorded, so it is proposed to conduct a study to describe the behavior of congenital disease in the Venezuelan population. Methodology: A prospective, observational study was carried out, including all children who attended the Pediatric Infectious Disease consultation at the University Hospital of Caracas between August 2016 and March 2018 with a diagnosis of microcephaly and / or those with suspected or confirmed exposure to the Zika virus during pregnancy, being evaluated by physical examination and paraclinical studies. All patients were evaluated by a multidisciplinary team. Results: Twenty-eight patients were included, prevailing the female gender with 53.6 %, 60.7 % of the patients presented microcephaly. Skeletal malformations were observed: arthrogryposis, equinovar foot, valgus foot, ocular affections: endotropia, congenital cataract, bilateral leukocoria, microphthalmia. In 28.6 % of patients, malformations were not observed. Confirmed cases were observed for Zika, with microcephaly and TAC of the skull with ventriculomegaly, as well as patients with normal cephalic circumference (cc) and imaging studies without alterations. Two cases are reported with normal CC at birth and progression to microcephaly in successive consultations. Conclusions: The Zika virus is associated with a genetic syndrome characterized by microcephaly, musculoskeletal and ophthalmological malformations. Microcephaly in Zika virus infection can develop in the postnatal period.

Assessing Therapeutic Efficacy in Real-time by Hyperpolarized Magnetic Resonance Metabolic Imaging.

Precisely measuring tumor-associated alterations in metabolism clinically will enable the efficient assessment of therapeutic responses. Advances in imaging technologies can exploit the differences in cancer-associated cell metabolism as compared to normal tissue metabolism, linking changes in target metabolism to therapeutic efficacy. Metabolic imaging by Positron Emission Tomography (PET) employing 2-fluoro-deoxy-glucose ([18F]FDG) has been used as a routine diagnostic tool in the clinic. Recently developed hyperpolarized Magnetic Resonance (HP-MR), which radically increases the sensitivity of conventional MRI, has created a renewed interest in functional and metabolic imaging. The successful translation of this technique to the clinic was achieved recently with measurements of 13C-pyruvate metabolism. Here, we review the potential clinical roles for metabolic imaging with hyperpolarized MRI as applied in assessing therapeutic intervention in different cancer systems.

[Comparative analysis of diagnostic scales of acute appendicitis: Alvarado, RIPASA and AIR]. / ARTÍCULO ORIGINAL Análisis comparativo de escalas diagnósticas de apendicitis aguda: Alvarado, RIPASA y AIR.

INTRODUCTION: Acute appendicitis is the most common surgical disease in emergency surgery, however, it remains a diagnostic problem and represents a challenge despite the experience and the different clinical and paraclinical diagnostic methods. OBJECTIVE: To evaluate in a comparative way the scale of Alvarado, AIR and RIPASA to determine which one is best as a diagnostic test of acute appendicitis in our population in order to arrive to an accurate diagnosis in the shortest possible time and cost. METHOD: Observational, prospective, transversal and comparative study of 137 patients to whom the scale of Alvarado, AIR and RIPASA was applied, who entered the emergency service of the Civil Hospital of Culiacán (México) with abdominal pain syndrome suggestive of acute appendicitis. RESULTS: The Alvarado scale presented sensitivity 97.2% and specificity of 27.6%. AIR presented sensitivity of 81.9% and specificity of 89.5%. RIPASA showed the same results as Alvarado. All tests showed diagnostic accuracy above 80. CONCLUSIONS: Alvarado and RIPASA presented good sensitivity, however, AIR is more specific, and has better accuracy for the diagnosis of acute appendicitis, making a better screening and thus reducing unnecessary surgeries. Therefore, it is recommended to use more AIR than Alvarado and RIPASA.

INTRODUCCIÓN: La apendicitis aguda es la enfermedad quirúrgica más común en cirugía de urgencia; sin embargo, sigue siendo un problema diagnóstico y representa un reto a pesar de la experiencia y los diferentes métodos de diagnóstico clínicos y paraclínicos. OBJETIVO: Evaluar en forma comparativa las escalas de Alvarado, AIR y RIPASA para determinar cuál es superior como prueba diagnóstica de apendicitis aguda en nuestra población, llegando a un diagnóstico preciso en el menor tiempo y costo posibles. MÉTODO: Estudio observacional, prospectivo, transversal y comparativo de 137 pacientes a quienes se aplicó las escalas de Alvarado, AIR y RIPASA, que ingresaron al servicio de urgencias del Hospital Civil de Culiacán (México) con síndrome doloroso abdominal sugestivo de apendicitis aguda. RESULTADOS: La escala de Alvarado presentó una sensibilidad del 97.2% y una especificidad del 27.6%. AIR tuvo una sensibilidad del 81.9% y una especificidad del 89.5%. RIPASA arrojó los mismos resultados que Alvarado. Todas las pruebas tuvieron una exactitud diagnóstica por arriba del 80. CONCLUSIONES: Alvarado y RIPASA presentaron buena sensibilidad, mientras que AIR es más específica y tiene mayor exactitud diagnóstica de apendicitis aguda, realizando un mejor tamizaje y permitiendo disminuir las cirugías innecesarias, por lo que se recomienda usar más AIR que Alvarado y RIPASA.

Inhibition of the hexosamine biosynthetic pathway promotes castration-resistant prostate cancer.

The precise molecular alterations driving castration-resistant prostate cancer (CRPC) are not clearly understood. Using a novel network-based integrative approach, here, we show distinct alterations in the hexosamine biosynthetic pathway (HBP) to be critical for CRPC. Expression of HBP enzyme glucosamine-phosphate N-acetyltransferase 1 (GNPNAT1) is found to be significantly decreased in CRPC compared with localized prostate cancer (PCa). Genetic loss-of-function of GNPNAT1 in CRPC-like cells increases proliferation and aggressiveness, in vitro and in vivo. This is mediated by either activation of the PI3K-AKT pathway in cells expressing full-length androgen receptor (AR) or by specific protein 1 (SP1)-regulated expression of carbohydrate response element-binding protein (ChREBP) in cells containing AR-V7 variant. Strikingly, addition of the HBP metabolite UDP-N-acetylglucosamine (UDP-GlcNAc) to CRPC-like cells significantly decreases cell proliferation, both in-vitro and in animal studies, while also demonstrates additive efficacy when combined with enzalutamide in-vitro. These observations demonstrate the therapeutic value of targeting HBP in CRPC.

The autophagy inhibitor chloroquine targets cancer stem cells in triple negative breast cancer by inducing mitochondrial damage and impairing DNA break repair.

Triple negative breast cancer (TNBC), characterized by an abundance of treatment-resistant breast cancer stem cells (CSCs), has a poorer prognosis than other types of breast cancers. Despite its aggressiveness, no effective targeted therapy exists for TNBC. Here, we demonstrate that CQ effectively targets CSCs via autophagy inhibition, mitochondrial structural damage, and impairment of double-stranded DNA break repair. Electron microscopy demonstrates CQ-induced mitochondrial cristae damage, which leads to mitochondrial membrane depolarization with a significant reduction in the activity of cytochrome c oxidase and accumulation of superoxide and double-stranded DNA breaks. CQ effectively diminishes the TNBC cells' ability to metastasize in vitro and in a TNBC xenograft model. When administered in combination with carboplatin, CQ effectively inhibits carboplatin-induced autophagy. This combination treatment significantly diminishes the expression of DNA repair proteins in CSC subpopulations, resulting in tumor growth reduction in carboplatin-resistant BRCA1 wild-type TNBC orthotopic xenografts. As TNBC's high treatment failure rate has been attributed to enrichment of CSCs, CQ, an autophagy inhibitor with anti-CSC effects, may be an effective adjunct to current TNBC chemotherapy regimens with carboplatin.

Multilevel Genomics-Based Taxonomy of Renal Cell Carcinoma.

On the basis of multidimensional and comprehensive molecular characterization (including DNA methalylation and copy number, RNA, and protein expression), we classified 894 renal cell carcinomas (RCCs) of various histologic types into nine major genomic subtypes. Site of origin within the nephron was one major determinant in the classification, reflecting differences among clear cell, chromophobe, and papillary RCC. Widespread molecular changes associated with TFE3 gene fusion or chromatin modifier genes were present within a specific subtype and spanned multiple subtypes. Differences in patient survival and in alteration of specific pathways (including hypoxia, metabolism, MAP kinase, NRF2-ARE, Hippo, immune checkpoint, and PI3K/AKT/mTOR) could further distinguish the subtypes. Immune checkpoint markers and molecular signatures of T cell infiltrates were both highest in the subtype associated with aggressive clear cell RCC. Differences between the genomic subtypes suggest that therapeutic strategies could be tailored to each RCC disease subset.

Vitamin D prevents endothelial damage induced by increased neutrophil extracellular traps formation in patients with systemic lupus erythematosus.

AIM: to investigate the effects of Vitamin D calcitriol/1,25(OH)2D3 on NETosis in systemic lupus erythematosus (SLE) patients with hypovitamin D. METHODS: neutrophlis of five SLE patients with hypovitamin D were divided into 4 groups, P0 (0 nM/control), P1 (1 nM), P2 (10 nM), and P3 (100 nM) as cultured samples. Phorbol Myristate Acetate (PMA) was used to stimulate NETs formation. The supernatant was separated and cocultured with HUVECs. Externalization of Neutrophil Elastase (NE) and Myeloperoxidase (MPO) during NETosis was measured by immunofluorescence and ELISA respectively. Early and late apoptosis of endothelial cell was measured by flowcytometry using cell death kit (Annexin V and PI antibody). RESULTS: this study showed significant decrease in early apoptosis with 10 nM of 1,25(OH)2D3 compared to control group. Significance of NE externalization found in all treatment groups (p<0.05), while MPO absorbance in the same tendency but not statistically significant. Further analysis also found a moderate positive correlation between NE externalizations with early apoptosis. CONCLUSION: vitamin D 1,25(OH)2D3 could reduce endothelial damage by decreasing NETosis activity. This result may reveal the possibility of Vitamin D as supplementary therapy for SLE patients with hypovitamin D to prevent endothelial damage.

The somatic genomic landscape of chromophobe renal cell carcinoma.

We describe the landscape of somatic genomic alterations of 66 chromophobe renal cell carcinomas (ChRCCs) on the basis of multidimensional and comprehensive characterization, including mtDNA and whole-genome sequencing. The result is consistent that ChRCC originates from the distal nephron compared with other kidney cancers with more proximal origins. Combined mtDNA and gene expression analysis implicates changes in mitochondrial function as a component of the disease biology, while suggesting alternative roles for mtDNA mutations in cancers relying on oxidative phosphorylation. Genomic rearrangements lead to recurrent structural breakpoints within TERT promoter region, which correlates with highly elevated TERT expression and manifestation of kataegis, representing a mechanism of TERT upregulation in cancer distinct from previously observed amplifications and point mutations.

Mitochondria of highly metastatic breast cancer cell line MDA-MB-231 exhibits increased autophagic properties.

Autophagy is a cellular housekeeping process that removes damaged or unwanted cellular components and recycles them to build new constituents. It is essential for tumor growth under adverse environment. Mitochondria play an important role in the formation of autophagosome and its subsequent docking and fusion with lysosome. To understand the contribution of mitochondria to the regulation of homeostatic autophagy in cancer cells, we used the transmitochondrial cytoplasmic hybrid (cybrid) model. Cybrid system allowed us to compare mitochondria from different cell types including highly metastatic breast cancer cell line MDA-MB-231 (c231), less metastatic breast cancer cell lines: MDA-MB-436 (c436) and MDA-MB-468 (c468), as well as non-cancerous mammary epithelial cell MCF-10A (c10A) in a defined nuclear background. The c231 exhibited lower LC3-II levels but higher ratio of LC3-II/LC3-I than c436, c468 and c10A. In addition, c231 displayed more punctate LC3-positive cells and had lower levels of sequestosome 1 (p62/SQSTM1) than other cybrids. These suggested that mitochondria could contribute to the increased autophagy and autophagic flux in metastatic cancer. This increased autophagy was found to be non-selective autophagy instead of selective mitophagy since LC3 puncta in c231 did not co-localize with mitochondria labeled by Mitotracker red or Tomm 20. The promotion of mitochondrial permeability transition (MPT) in c231 also contributed to increased autophagy. Block of MPT by the inhibition of low-conductance stage of MPT pores resulted in a decrease of LC3 puncta in c231. These results suggested that mitochondria from highly metastatic breast cancer cell line MDA-MB-231 can promote homeostatic autophagy of cancer through opening low-conductance MPT pores.

SAFB1 mediates repression of immune regulators and apoptotic genes in breast cancer cells.

The scaffold attachment factors SAFB1 and SAFB2 are paralogs, which are involved in cell cycle regulation, apoptosis, differentiation, and stress response. They have been shown to function as estrogen receptor corepressors, and there is evidence for a role in breast tumorigenesis. To identify their endogenous target genes in MCF-7 breast cancer cells, we utilized a combined approach of chromatin immunoprecipitation (ChIP)-on-chip and gene expression array studies. By performing ChIP-on-chip on microarrays containing 24,000 promoters, we identified 541 SAFB1/SAFB2-binding sites in promoters of known genes, with significant enrichment on chromosomes 1 and 6. Gene expression analysis revealed that the majority of target genes were induced in the absence of SAFB1 or SAFB2 and less were repressed. Interestingly, there was no significant overlap between the genes identified by ChIP-on-chip and gene expression array analysis, suggesting regulation through regions outside the proximal promoters. In contrast to SAFB2, which shared most of its target genes with SAFB1, SAFB1 had many unique target genes, most of them involved in the regulation of the immune system. A subsequent analysis of the estrogen treatment group revealed that 12% of estrogen-regulated genes were dependent on SAFB1, with the majority being estrogen-repressed genes. These were primarily genes involved in apoptosis, such as BBC3, NEDD9, and OPG. Thus, this study confirms the primary role of SAFB1/SAFB2 as corepressors and also uncovers a previously unknown role for SAFB1 in the regulation of immune genes and in estrogen-mediated repression of genes.

Health system and personal barriers resulting in decreased utilization of HIV and STD testing services among at-risk black men who have sex with men in Massachusetts.

Testing for HIV and other sexually transmitted diseases (STD) remains a cornerstone of public health prevention interventions. This analysis was designed to explore the frequency of testing, as well as health system and personal barriers to testing, among a community-recruited sample of Black men who have sex with men (MSM) at risk for HIV and STDs. Black MSM (n = 197) recruited via modified respondent-driven sampling between January and July 2008 completed an interviewer-administered assessment, with optional voluntary HIV counseling and testing. Logistic regression procedures examined factors associated with not having tested in the 2 years prior to study enrollment for: (1) HIV (among HIV-uninfected participants, n = 145) and (2) STDs (among the entire mixed serostatus sample, n = 197). The odds ratios and their 95% confidence intervals obtained from this analysis were converted to relative risks. (1) HIV: Overall, 33% of HIV-uninfected Black MSM had not been tested for HIV in the 2 years prior to study enrollment. Factors uniquely associated with not having a recent HIV test included: being less educated; engaging in serodiscordant unprotected sex; and never having been HIV tested at a community health clinic, STD clinic, or jail. (2) STDs: Sixty percent had not been tested for STDs in the 2 years prior to study enrollment, and 24% of the sample had never been tested for STDs. Factors uniquely associated with not having a recent STD test included: older age; having had a prior STD; and never having been tested at an emergency department or urgent care clinic. Overlapping factors associated with both not having had a recent HIV or STD test included: substance use during sex; feeling that using a condom during sex is "very difficult"; less frequent contact with other MSM; not visiting a health care provider (HCP) in the past 12 months; having a HCP not recommend HIV or STD testing at their last visit; not having a primary care provider (PCP); current PCP never recommending they get tested for HIV or STDs. In multivariable models adjusting for relevant demographic and behavioral factors, Black MSM who reported that a HCP recommended getting an HIV test (adjusted relative risk [ARR] = 0.26; p = 0.01) or STD test (ARR = 0.11; p = 0.0004) at their last visit in the past 12 months were significantly less likely to have not been tested for HIV or STDs in the past 2 years. Many sexually active Black MSM do not regularly test for HIV or STDs. HCPs play a pivotal role in encouraging testing for Black MSM. Additional provider training is warranted to educate HCPs about the specific health care needs of Black MSM, in order to facilitate access to timely, culturally competent HIV and STD testing and treatment services for this population.