Hypomethylation at H19DMR in penile squamous cell carcinoma is not related to HPV infection.

Penile squamous cell carcinoma (SCC) is a rare and aggressive tumour mainly related to lifestyle behaviour and human papillomavirus (HPV) infection. Environmentally induced loss of imprinting (LOI) at the H19 differentially methylated region (H19DMR) is associated with many cancers in the early events of tumorigenesis and may be involved in the pathogenesis of penile SCC. We sought to evaluate the DNA methylation pattern at H19DMR and its association with HPV infection in men with penile SCC by bisulfite sequencing (bis-seq). We observed an average methylation of 32.2% ± 11.6% at the H19DMR of penile SCC and did not observe an association between the p16INK4a+ (p = 0.59) and high-risk HPV+ (p = 0.338) markers with methylation level. The average methylation did not change according to HPV positive for p16INK4a+ or hrHPV+ (35.4% ± 10%) and negative for both markers (32.4% ± 10.1%) groups. As the region analysed has a binding site for the CTCF protein, the hypomethylation at the surrounding CpG sites might alter its insulator function. In addition, there was a positive correlation between intense polymorphonuclear cell infiltration and hypomethylation at H19DMR (p = 0.035). Here, we report that hypomethylation at H19DMR in penile SCC might contribute to tumour progression and aggressiveness regardless of HPV infection.

Impact of orange juice containing potentially prebiotic ingredients on human gut microbiota composition and its metabolites.

Orange juice containing oligosaccharides and dextran was assessed, after in vitro digestion, in a fermentative system with fecal microbiota from two donors (A and B) in anaerobiosis (37 °C/48 h). Microbiota analysis was performed using 16S rRNA sequencing, and HPLC quantified the metabolites. Oligosaccharides and dextran were resistant to digestion and were consumed during colonic fermentation. Lactate and acetate were the main metabolites, followed by butyrate, propionate, and isobutyrate. High propionate accumulation and fast consumption of oligosaccharides were observed for donor B. Lactobacillus ruminis (44.96 %) presented an increased relative abundance for donor A. Bifidobacterium adolescentis (41.73 %) was remarkable for donor B after fermentation. In addition, the functional orange juice promoted the growth of emerging probiotics such as Bacteroides xylanisolvens and reduced some strains, such as Clostridia sp. Thus, the potentially prebiotic orange juice enhances gut microbiota composition and might be a suitable product for the functional food market.

True or false: what are the factors that influence COVID-19 diagnosis by RT-qPCR?

INTRODUCTION: The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease has had a catastrophic impact on the world resulting in several deaths. Since World Health Organization declared the pandemic status of the disease, several molecular diagnostic kits have been developed to help the tracking of viruses spread. AREAS COVERED: This review aims to describe and evaluate the currently reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) diagnosis kit. Several processes used in COVID-19 diagnostic procedures are detailed in further depth to demonstrate optimal practices. Therefore, we debate the main factors that influence the viral detection of SARS-COV-2 and how they can affect the diagnosis of patients. EXPERT OPINION: Here is highlighted and discussed several factors that can interfere in the RT-PCR analysis, such as the viral load of the sample, collection site, collection methodology, sample storage, transport, primer, and probe mismatch/dimerization in different brand kits. This is a pioneer study to discuss the factor that could lead to the wrong interpretation of RT-qPCR diagnosis of SARS-CoV-2. This study aimed to help the readers to understand what very likely is behind a bad result of SARS-CoV-2 detection by RT-PCR and what could be done to reach a reliable diagnosis.