Folate, genomic stability and colon cancer: the use of single cell gel electrophoresis in assessing the impact of folate in vitro, in vivo and in human biomonitoring.

Intake of folate (vitamin B9) is strongly inversely linked with human cancer risk, particularly colon cancer. In general, people with the highest dietary intake of folate or with high blood folate levels are at a reduced risk (approx. 25%) of developing colon cancer. Folate acts in normal cellular metabolism to maintain genomic stability through the provision of nucleotides for DNA replication and DNA repair and by regulating DNA methylation and gene expression. Folate deficiency can accelerate carcinogenesis by inducing misincorporation of uracil into DNA, by increasing DNA strand breakage, by inhibiting DNA base excision repair capacity and by inducing DNA hypomethylation and consequently aberrant gene and protein expression. Conversely, increasing folate intake may improve genomic stability. This review describes key applications of single cell gel electrophoresis (the comet assay) in assessing genomic instability (misincorporated uracil, DNA single strand breakage and DNA repair capacity) in response to folate status (deficient or supplemented) in human cells in vitro, in rodent models and in human case-control and intervention studies. It highlights an adaptation of the SCGE comet assay for measuring genome-wide and gene-specific DNA methylation in human cells and colon tissue

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

Association between Azospirillum brasilense and strawberry plants (Fragaria ananassa): chemotaxis and root colonization

La colonización rizosférica y endofítica de Azospirillum brasilense-REC3 en raíces de frutilla (Fragaria ananassa Duch.) fue analizada a nivel de ultraestructura. Observaciones por microscopia electrónica de barrido en plantas inoculadas mostraron que Azospirillum se adhiere firmemente a la superficie radicular por una red de material tipo fibrilar, y que también está asociado con material de tipo granular acumulado en la superficie radicular. Se observaron dos patrones de adsorción celular superficial: células simples, distribuidas al azar y pequeños agregados celulares. Para verificar la colonización endofítica de esta cepa, la misma fue marcada con el gen de la proteína verde fluorescente (gfp) y observada en tejidos radiculares de frutilla por microscopía de fluorescencia y electrónica de transmisión. El análisis ultraestructural mostró cualitativamente más células de A. brasilense-REC3 asociadas con raíces de la variedad ´Camarosa que con ´Selva´. Esto fue confirmado por el NMP de bacterias asociadas con cada variedad, indicando que una mejor colonización estaría dependiendo de la combinación de genotipos asociados entre planta y bacteria. Los exudados radiculares constituyen una fuente importante de nutrientes para los microorganismos en la rizósfera y participan en el proceso de colonización a través de la quimiotáxis de los microorganismos en el suelo. En el caso de plantas de frutilla, los exudados radiculares de tres variedades produjeron quimiotáxis positiva en diferentes cepas de A. brasilense. Dicho efecto fue mayor en cepas endofíticas que en las que colonizan superficialmente a las raíces, y dependiente de la variedad de frutilla, de la concentración y tiempo de recolección de los exudados. De esta forma se destaca el papel de la quimiotáxis como punto de partida para lograr una asociación exitosa entre planta y bacteria.Fil: Pedraza, Raúl Osvaldo. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Guerrero Molina, María Fernanda. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Winik, Beatriz Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Tortora, María L.. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Ragout, Alicia Leonor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Dos Santos Teixeira, Katia Regina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Baca, Beatríz E.. Benemérita Universidad Autónoma de Puebla; Méxic

Cancer glycolytic dependence as an new target of olive leaf extract

Oleuropein (Ole), the main bioactive phenolic component of Olea europaea L. has recently attracted the scientific attention for its several beneficial properties, including its anticancer effects. This study is intended to investigate whether an olive leaf extract enriched in Ole (OLEO) may counteract the aerobic glycolysis exploited by tumor cells. We found that OLEO decreased melanoma cell proliferation and motility. OLEO was also able to reduce the rate of glycolysis of human melanoma cells without affecting oxidative phosphorylation. This reduction was associated with a significant decrease of glucose transporter-1, protein kinase isoform M2 and monocarboxylate transporter-4 expression, possible drivers of such glycolysis inhibition. Extending the study to other tumor histotypes, we observed that the metabolic effects of OLEO are not confined to melanoma, but also confirmed in colon carcinoma, breast cancer and chronic myeloid leukemia. In conclusion, OLEO represents a natural product effective in reducing the glycolytic metabolism of different tumor types, revealing an extended metabolic inhibitory activity that may be well suited in a complementary anti-cancer therapy

Importance of Lysine 79 in Apoptosis Induced by Mutant Forms of Cytochrome C

Univ Mogi das Cruzes, São Paulo, BrazilUniv Republica, Montevideo, UruguayUniversidade Federal de São Paulo, São Paulo, BrazilUniv Fed ABC, Sao Bernardo Do Campo, SP, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc

Cognitive and White Matter Microstructure Development in Congenital Hypothyroidism and Familial Thyroid Disorders

Children with congenital hypothyroidism (CH) are at risk for suboptimal neurodevelopment

Maintenance Olaparib for Germline BRCA-Mutated Metastatic Pancreatic Cancer

BACKGROUND: Patients with a germline BRCA1 or BRCA2 mutation make up a small subgroup of those with metastatic pancreatic cancer. The poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor olaparib has had antitumor activity in this population. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 3 trial to evaluate the efficacy of olaparib as maintenance therapy in patients who had a germline BRCA1 or BRCA2 mutation and metastatic pancreatic cancer and disease that had not progressed during first-line platinum-based chemotherapy. Patients were randomly assigned, in a 3:2 ratio, to receive maintenance olaparib tablets (300 mg twice daily) or placebo. The primary end point was progression-free survival, which was assessed by blinded independent central review. RESULTS: Of the 3315 patients who underwent screening, 154 underwent randomization and were assigned to a trial intervention (92 to receive olaparib and 62 to receive placebo). The median progression-free survival was significantly longer in the olaparib group than in the placebo group (7.4 months vs. 3.8 months; hazard ratio for disease progression or death, 0.53; 95% confidence interval [CI], 0.35 to 0.82; P = 0.004). An interim analysis of overall survival, at a data maturity of 46%, showed no difference between the olaparib and placebo groups (median, 18.9 months vs. 18.1 months; hazard ratio for death, 0.91; 95% CI, 0.56 to 1.46; P = 0.68). There was no significant between-group difference in health-related quality of life, as indicated by the overall change from baseline in the global quality-of-life score (on a 100-point scale, with higher scores indicating better quality of life) based on the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (between-group difference, -2.47 points; 95% CI, -7.27 to 2.33). The incidence of grade 3 or higher adverse events was 40% in the olaparib group and 23% in the placebo group (between-group difference, 16 percentage points; 95% CI, -0.02 to 31); 5% and 2% of the patients, respectively, discontinued the trial intervention because of an adverse event. CONCLUSIONS: Among patients with a germline BRCA mutation and metastatic pancreatic cancer, progression-free survival was longer with maintenance olaparib than with placebo. (Funded by AstraZeneca and others; POLO ClinicalTrials.gov number, NCT02184195.).status: publishe