Antioxidant, α-glucosidase inhibitory activities, and HPLC quantitative analysis of phenolic compounds isolated from Neptunia oleracea Lour.

Neptunia oleracea Lour. is a tropical plant cultivated in Southeast Asia. It is consumed as vegetable and traditional herb for the treatment of several disorders. The objective of the present work was to isolate the phenolic compounds from N. oleracea, followed by their bioactivity evaluation and quantitative analysis. The ethyl acetate (EtOAc) and methanol (MeOH) fractions of N. oleracea were subjected to various chromatographic techniques to isolate the phenolic compounds. The isolated phenolic compounds were characterised by several spectroscopic methods, including mass spectrometry (MS) and nuclear magnetic resonance (NMR). Then, these compounds were subjected to DPPH free radical scavenging as α-glucosidase inhibitory assays for the evaluation of their activities. Their contents in the fractions were analysed via high performance liquid chromatography (HPLC) quantitative analysis. Five phenolic compounds including quercetin-3-O-β-D-xylopyranoside (1), quercetin-3-O-α-L-arabinopyranoside (2), quercetin-3-O-α-L-rhamnoside (3), methylgallate (4) and rutin (5) were isolated from N. oleracea for the first time. Evaluation on the DPPH free radical scavenging and α-glucosidase inhibitory activities of these compounds showed that methylgallate (4) was the most potent antioxidant and α-glucosidase inhibitors among them, with IC50 values of 17.25 and 50.76 μM, respectively. The HPLC quantitative analysis revealed the high content of the quercetin derivatives (compounds 1, 2 and 3) in the EtOAc fraction (ranging from 125.68 to 157.55 μg/mg) and methylgallate (4) in the MeOH fraction (75.25 μg/mg). Comparison of the bioactivities of the isolated phenolic compounds with the fractions indicated their significant contribution for the DPPH free radical scavenging of N. oleracea; while they might be working synergistically for the α-glucosidase inhibitory activity. The results of the present work could help to validate the contribution of phenolic compounds for the studied bioactivities of N. oleracea

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

Impact of Smoking and Brain Metastasis on Outcomes of Advanced <i>EGFR</i> Mutation Lung Adenocarcinoma Patients Treated with First Line Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors

<div><p>Objectives</p><p>This purpose of this study was to examine clinical-pathologic factors – particularly smoking and brain metastases – in <i>EGFR</i> mutation positive (M+) lung adenocarcinoma (ADC) to determine their impact on survival in patients treated with first line EGFR TKI.</p><p>Methods</p><p>A retrospective review of <i>EGFR</i> mutation reflex testing experience for all ADC diagnosed at a tertiary Asian cancer centre from January 2009 to April 2013. Amongst this cohort, patients with advanced <i>EGFR</i> M+ ADC treated with first line EGFR TKI were identified to determine factors that influence progression free and overall survival.</p><p>Results</p><p>444/742 (59.8%) ADC reflex tested for <i>EGFR</i> mutations were <i>EGFR</i> M+. Amongst never-smokers (n=468), <i>EGFR</i> M+ were found in 74.5% of females and 76.3% of males, and amongst ever smokers (n=283), in 53.3% of females and 35.6% of males. Exon 20 mutations were found more commonly amongst heavy smokers (> 50 pack years and > 20 pack years, Pearson’s chi square p=0.044, and p=0.038 respectively). 211 patients treated with palliative first line TKI had a median PFS and OS of 9.2 and 19.6 months respectively. 26% of patients had brain metastasis at diagnosis. This was significantly detrimental to overall survival (HR 1.85, CI 1.09-3.16, p=0.024) on multivariate analysis. There was no evidence that smoking status had a significant impact on survival.</p><p>Conclusions</p><p>The high prevalence of <i>EGFR</i> M+ in our patient population warrants reflex testing regardless of gender and smoking status. Smoking status and dosage did not impact progression free or overall survival in patients treated with first line EGFR TKI. The presence of brain metastasis at diagnosis negatively impacts overall survival.</p></div

Univariate analysis of progression free survival and overall survival.

<p>Univariate analysis of progression free survival and overall survival.</p

Kaplan-Meier plots of cohort of 211 patients treated with 1^st line EGFR TKI; (a) PFS by brain metastasis in ECOG 0–1 patients, (b) PFS by brain metastasis in ECOG 2–4 patients, (c) OS by brain metastasis in ECOG 0–1 patients, and (d) OS by brain metastasis in ECOG 2–4 patients.

<p>Kaplan-Meier plots of cohort of 211 patients treated with 1^st line EGFR TKI; (a) PFS by brain metastasis in ECOG 0–1 patients, (b) PFS by brain metastasis in ECOG 2–4 patients, (c) OS by brain metastasis in ECOG 0–1 patients, and (d) OS by brain metastasis in ECOG 2–4 patients.</p

Sites of EGFR mutations amongst 461 patients.

<p>Sites of EGFR mutations amongst 461 patients.</p

Clinical characteristics and <i>EGFR</i> mutation status rates categorised by smoking status and sex.

<p>11 patients with unknown smoking status, and 6 who had samples indeterminate for <i>EGFR</i> mutational status were excluded. 464/762 (60.9%) tested positive for <i>EGFR</i> mutations (<i>EGFR</i> M+). The number of patients needed to test in order to pick up 1 <i>EGFR</i> mutant lung adenocarcinoma in any sub-population stratified by sex and smoking status, was less than 3 patients (male ES; 1/0.357 = 2.8).</p

<i>EGFR</i> mutation rates amongst ever smokers classified by pack years.

<p><i>EGFR</i> mutation rates amongst ever smokers classified by pack years.</p