Molecular detection of exosomal miRNAs of blood serum for prognosis of colorectal cancer.

Colorectal cancer (CRC) is the third most common cancer affecting people. The discovery of new, non-invasive, specific, and sensitive molecular biomarkers for CRC may assist in the diagnosis and support therapeutic decision making. Exosomal miRNAs have been demonstrated in carcinogenesis and CRC development, which makes these miRNAs strong biomarkers for CRC. Deep sequencing allows a robust high-throughput informatics investigation of the types and abundance of exosomal miRNAs. Thus, exosomal miRNAs can be efficiently examined as diagnostic biomarkers for disease screening. In the present study, a number of 660 mature miRNAs were detected in patients diagnosed with CRC at different stages. Of which, 29 miRNAs were differentially expressed in CRC patients compared with healthy controls. Twenty-nine miRNAs with high abundance levels were further selected for subsequent analysis. These miRNAs were either highly up-regulated (e.g., let-7a-5p, let-7c-5p, let-7f-5p, let-7d-3p, miR-423-5p, miR-3184-5p, and miR-584) or down-regulated (e.g., miR-30a-5p, miR-99-5p, miR-150-5p, miR-26-5p and miR-204-5p). These miRNAs influence critical genes in CRC, leading to either tumor growth or suppression. Most of the reported diagnostic exosomal miRNAs were shown to be circulating in blood serum. The latter is a novel miRNA that was found in exosomal profile of blood serum. Some of the predicted target genes of highly expressed miRNAs participate in several cancer pathways, including CRC pathway. These target genes include tumor suppressor genes, oncogenes and DNA repair genes. Main focus was given to multiple critical signaling cross-talking pathways including transforming growth factor ß (TGFß) signaling pathways that are directly linked to CRC. In conclusion, we recommend further analysis in order to experimentally confirm exact relationships between selected differentially expressed miRNAs and their predicted target genes and downstream functional consequences.

Lipid distributions in the Global Diagnostics Network across five continents.

AIMS: Lipids are central in the development of cardiovascular disease, and the present study aimed to characterize variation in lipid profiles across different countries to improve understanding of cardiovascular risk and opportunities for risk-reducing interventions. METHODS AND RESULTS: This first collaborative report of the Global Diagnostics Network (GDN) evaluated lipid distributions from nine laboratory organizations providing clinical laboratory testing in 17 countries on five continents. This cross-sectional study assessed aggregated lipid results from patients aged 20-89 years, tested at GDN laboratories, from 2018 through 2020. In addition to mean levels, the World Health Organization total cholesterol risk target (<5.00 mmol/L, <193 mg/dL) and proportions in guideline-based low-density lipoprotein cholesterol (LDL-C) categories were assessed. This study of 461 888 753 lipid results found wide variation by country/region, sex, and age. In most countries, total cholesterol and LDL-C peaked at 50-59 years in females and 40-49 years in males. Sex- and age-group adjusted mean total cholesterol levels ranged from 4.58 mmol/L (177.1 mg/dL) in the Republic of Korea to 5.40 mmol/L (208.8 mg/dL) in Austria. Mean total cholesterol levels exceeded the World Health Organization target in Japan, Australia, North Macedonia, Switzerland, Germany, Slovakia, and Austria. Considering LDL-C categories, North Macedonia had the highest proportions of LDL-C results >4.91 mmol/L (>190 mg/dL) for both females (9.9%) and males (8.7%). LDL-C levels <1.55 mmol/L (<60 mg/dL) were most common among females in Canada (10.7%) and males in the UK (17.3%). CONCLUSION: With nearly a half billion lipid results, this study sheds light on the worldwide variability in lipid levels, which may reflect inter-country differences in genetics, lipid testing, lifestyle habits, and pharmacologic treatment. Despite variability, elevated atherogenic lipid levels are a common global problem, and these results can help inform national policies and health system approaches to mitigate lipid-mediated risk of cardiovascular disease.

O6-Methylguanine-DNA Methyltransferase and ATP-Binding Cassette Membrane Transporter G2 Promotor Methylation: Can Predict the Response to Chemotherapy in Advanced Breast Cancer?

Background: ATP-binding cassette membrane transporter G2 (ABCG2) gene is one of transporter family and well characterized for their association with chemoresistance. Promoter methylation is a mechanism for regulation of gene expression. O6-Methyl guanine DNA methyl transferase (MGMT) gene plays a fundamental role in DNA repair. MGMT has the ability to remove alkyl adducts from DNA at the O6 position of guanine. Alkylating agents exert their function through adding these alkyls adducts to DNA leading to cell death unless it is repaired by MGMT. MGMT promoter was found to be methylated in several malignancies. The aim of the present work is to study the relation of MGMT and ABCG2 promoter methylation status in advanced breast cancer patients to response to cyclophosphamide-doxorubicin (AC) based therapeutic regime. Methods: This retrospective study included Forty-two female patients with advanced breast cancer assessed before receiving chemotherapy and after the completion of regimens. They were grouped into responders and non-responders according to RECIST criteria. Methylation analysis of MGMT and ABCG2 genes were performed on breast cancer tissues. Results: MGMT promoter was methylated in 40.5% of the cases. ABCG2 promoter was methylated in 14.3% of cases. There was no statistically significant association between MGMT and ABCG2 promoter methylation status and clinicopathological parameters. There was statistically significant association between methylation status of both promoters and response to AC when followed by Taxane. Conclusion: Methylation of MGMT and ABCG2 promoters combined could be a potential predictive factor for response to cyclophosphamide-doxorubicin based therapeutic regime.

Establishment of reference intervals of clinical chemistry analytes for the adult population in Egypt.

BACKGROUND: This is the first Egyptian nationwide study for derivation of reference intervals (RIs) for 34 major chemistry analytes. It was conducted as a part of the global initiative by the IFCC Committee on Reference Intervals and Decision Limits (C-RIDL) for establishing country-specific RIs based on a harmonized protocol. METHODS: 691 apparently healthy volunteers aged ≥18 years were recruited from multiple regions in Egypt. Serum specimens were analyzed in two centers. The harmonization and standardization of test results were achieved by measuring value-assigned serum panel provided by C-RIDL. The RIs were calculated by parametric method. Sources of variation of reference values (RVs) were evaluated by multiple regression analysis. The need for partitioning by sex, age, and region was judged primarily by standard deviation ratio (SDR). RESULTS: Gender-specific RIs were required for six analytes including total bilirubin (TBil), aspartate and alanine aminotransferase (AST, ALT). Seven analytes required age-partitioning including glucose and low-density lipoprotein cholesterol (LDL-C). Regional differences were observed between northern and southern Egypt for direct bilirubin, glucose, and high-density-lipoprotein cholesterol (HDL-C) with all their RVs lower in southern Egypt. Compared with other collaborating countries, the features of Egyptian RVs were lower HDL-C and TBil and higher TG and C-reactive protein. In addition, BMI showed weak association with most of nutritional markers. These features were shared with two other Middle Eastern countries: Saudi Arabia and Turkey. CONCLUSION: The standardized RIs established by this study can be used as common Egyptian RI, except for a few analytes that showed regional differences. Despite high prevalence of obesity among Egyptians, their RVs of nutritional markers are less sensitive to increased BMI, compared to other collaborating countries.

A clinical and immunological study of children with chronic hepatitis B virus infection.

AIM: To identify the clinical status and immunological profile of a cohort of children with chronic hepatitis B virus (HBV) infection to assess the short-term consequences of this infection. MATERIAL AND METHODS: This prospective case-control study included 30 children in the age range 1-15 years with positive HBsAg attending the Hepatology clinic of Alexandria University Children's Hospital. Twenty children received lamivudine (3 mg/kg, oral, once a day), and 10 children were lamivudine-resistant and received entecavir treatment (10-11 kg/0.3 mg to > 30 kg/1 mg). They were followed up every 3 months for 1 year. RESULTS: The study showed that 97% of the studied cases were discovered accidentally during routine investigations and only 3% presented by acute hepatitis. Ninety percent of them had family member infection with HBV, of which 70% were the mother. Eighty-seven percent of cases had no clinical signs, and only 13% of cases had hepatomegaly. All of the cases were HBsAg positive, 50% were HBeAg positive, 56.7% were HBeAb positive, 33.3% were HBcAb positive, and 100% were HBsAb negative. CONCLUSIONS: Most of children with HBV infection had associated family member infection and were accidentally discovered. Despite a marked decrease in HBV DNA level after treatment, there was no clearance of HBsAg and no HBsAb seroconversion. Screening for the HBsAb level in children with family members with HBV is recommended.

Amelioration of perivascular adipose inflammation reverses vascular dysfunction in a model of nonobese prediabetic metabolic challenge: potential role of antidiabetic drugs.

The onset of vascular impairment precedes that of diagnostic hyperglycemia in diabetic patients suggesting a vascular insult early in the course of metabolic dysfunction without a well-defined mechanism. Mounting evidence implicates adipose inflammation in the pathogenesis of insulin resistance and diabetes. It is not certain whether amelioration of adipose inflammation is sufficient to preclude vascular dysfunction in early stages of metabolic disease. Recent findings suggest that antidiabetic drugs, metformin, and pioglitazone, improve vascular function in prediabetic patients, without an indication if this protective effect is mediated by reduction of adipose inflammation. Here, we used a prediabetic rat model with delayed development of hyperglycemia to study the effect of metformin or pioglitazone on adipose inflammation and vascular function. At the end of the metabolic challenge, these rats were neither obese, hypertensive, nor hyperglycemic. However, they showed increased pressor responses to phenylephrine and augmented aortic and mesenteric contraction. Vascular tissues from prediabetic rats showed increased Rho-associated kinase activity causing enhanced calcium sensitization. An elevated level of reactive oxygen species was seen in aortic tissues together with increased Transforming growth factor ß1 and Interleukin-1ß expression. Although, no signs of systemic inflammation were detected, perivascular adipose inflammation was observed. Adipocyte hypertrophy, increased macrophage infiltration, and elevated Transforming growth factor ß1 and Interleukin-1ß mRNA levels were seen. Two-week treatment with metformin or pioglitazone or switching to normal chow ameliorated adipose inflammation and vascular dysfunction. Localized perivascular adipose inflammation is sufficient to trigger vascular dysfunction early in the course of diabetes. Interfering with this inflammatory process reverses this early abnormality.