Phoenixin 20 ameliorates pulmonary arterial hypertension via inhibiting inflammation and oxidative stress.

Pulmonary arterial hypertension (PAH) is a severe pathophysiological syndrome resulting in heart failure, which is found to be induced by pulmonary vascular remodeling mediated by oxidative stress (OS) and inflammation. Phoenixin-20 (PNX-20) is a reproductive peptide first discovered in mice with potential suppressive properties against OS and inflammatory response. Our study will explore the possible therapeutic functions of PHN-20 against PAH for future clinical application. Rats were treated with normal saline, PHN-20 (100 ng/g body weight daily), hypoxia, hypoxia+PHN-20 (100 ng/g body weight daily), respectively. A signally elevated RVSP, mPAP, RV/LV + S, and W%, increased secretion of cytokines, enhanced malondialdehyde (MDA) level, repressed superoxide dismutase (SOD) activity, and activated NLRP3 signaling were observed in hypoxia-stimulated rats, which were notably reversed by PHN-20 administration. Pulmonary microvascular endothelial cells (PMECs) were treated with hypoxia with or without PHN-20 (10 and 20 nM). Marked elevation of inflammatory cytokine secretion, increased MDA level, repressed SOD activity, and activated NLRP3 signaling were observed in hypoxia-stimulated PMECs, accompanied by a downregulation of SIRT1. Furthermore, the repressive effect of PHN-20 on the domains-containing protein 3 (NLRP3) pathway in hypoxia-stimulated PMECs was abrogated by sirtuin1 (SIRT1) knockdown. Collectively, PHN-20 alleviated PAH via inhibiting OS and inflammation by mediating the transcriptional function of SIRT1.

Mutational landscape of homologous recombination-related genes in small-cell lung cancer.

BACKGROUND: Homologous recombination deficiency (HRD) is a well-known biomarker which could predict poly-ADP ribose polymerase 1 (PARP) inhibitor and platinum drug response. As an aggressive cancer, small-cell lung cancer (SCLC) is sensitive to platinum drugs, but relapse occurs rapidly. Herein, we aim to illustrate the genomic alteration patterns of homologous recombination repair (HRR)-related genes in a Chinese SCLC cohort and further analyze the relationship among HRR gene mutations and known biomarkers of immune checkpoint inhibitor (ICI) response, including tumor mutation burden (TMB) and programmed cell death-ligand 1 (PD-L1) expression. METHODS: Next-generation sequencing (NGS)-based target capture sequencing of 543 cancer-related genes was performed to analyze the genomic profiles of 133 Chinese SCLC patients, and TMB was calculated. PD-L1 expression was evaluated in 90 out of 133 patients using the SP142 PD-L1 immunohistochemistry assay. RESULTS: Among the 133 patients with SCLC, 47 (35.3%) had HRR gene mutations. ATM (8.3%) was the most frequently mutated HRR gene in the cohort, followed by NBN (4.5%). Pathogenic somatic and germline mutations of HRR genes were identified in 11 (23.4%) and 4 (8.5%) patients, respectively. HRR gene mutations cooccurred with KMT2D gene mutations. There were several differences in genomic alterations between patients with HRR gene mutations (HRR-Mut) and without HRR mutations (HRR-WT). The results revealed that TP53 and RB1 were commonly mutated genes in both groups. Mutations in the KMT2D gene and genes in the RTK-RAS pathway occurred more frequently in the HRR-Mut group. Furthermore, we found that mutations in HRR genes were associated with high TMB (Wilcoxon, p = 0.048), but there was no correlation of HRR gene mutation status with PD-L1 expression. CONCLUSIONS: We exhaustively describe the genomic alteration profile of Chinese SCLC patients and provide further evidence that HRR gene mutations are prevalent in SCLC patients.

Microarray analysis of genes with differential expression of m6A methylation in lung cancer.

PURPOSE: N6-methyladenosine (m6A) is among the most abundant mRNA modifications in eukaryote. The aim of the present study was to investigate function of m6A mRNA methylation in lung cancer and the underlying mechanism. METHODS: Microarray analysis was performed to detect the differences in RNA expression between cancerous and adjacent non-cancerous tissue samples. The target mRNAs were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Hierarchical clustering of RNAs was conducted to identify distinct m6A methylation or expression patterns between the samples. RESULTS: In the present study, some differentially expressed genes (DEGs) of mRNAs were identified, including up-regulated secret phosphoprotein 1 (SPP1) and down-regulated pRB. Functional enrichment analysis revealed that while differential hypermethylation was related to cell cycle, intracellular part and protein binding, the main pathway involved herpes simplex virus 1 infection related to down-regulated AKT, Araf1 and BCL2A1. In the meantime, sexual reproduction, cohesin complex and protein C-terminus binding was functionally linked to differential hypomethylation, while fluid shear stress and atherosclerosis were identified as the main pathways related to up-regulated GST and CNP. CONCLUSIONS: We showed that lung cancer development involved differential expression of SPP1 and pRB mRNA, as well as m6A mRNA methylation in AKT, APAF1, BCL2A1, GST and CNP genes.

A Ligation/Recombinase Polymerase Amplification Assay for Rapid Detection of SARS-CoV-2.

The pandemic of COVID-19 caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to more than 117 million reported cases and 2.6 million deaths. Accurate diagnosis technologies are vital for controlling this pandemic. Reverse transcription (RT)-based nucleic acid detection assays have been developed, but the strict sample processing requirement of RT has posed obstacles on wider applications. This study established a ligation and recombinase polymerase amplification (L/RPA) combined assay for rapid detection of SARS-CoV-2 on genes N and ORF1ab targeting the specific biomarkers recommended by the China CDC. Ligase-based strategies usually have a low-efficiency problem on RNA templates. This study has addressed this problem by using a high concentration of the T4 DNA ligase and exploiting the high sensitivity of RPA. Through selection of the ligation probes and optimization of the RPA primers, the assay achieved a satisfactory sensitivity of 101 viral RNA copies per reaction, which was comparable to RT-quantitative polymerase chain reaction (RT-qPCR) and other nucleic acid detection assays for SARS-CoV-2. The assay could be finished in less than 30 min with a simple procedure, in which the requirement for sophisticated thermocycling equipment had been avoided. In addition, it avoided the RT procedure and could potentially ease the requirement for sample processing. Once validated with clinical samples, the L/RPA assay would increase the practical testing availability of SARS-CoV-2. Moreover, the principle of L/RPA has an application potential to the identification of concerned mutations of the virus.

Phillygenin regulates proliferation and apoptosis of non-small cell lung cancer through by AMPK/ERK/NF-κB axis.

An increasing number of studies have demonstrated that phillygenin (PG) exerts anti-oxidant, anti-inflammatory and anti-cancer activities. However, the effects of PG on the proliferation and invasion in non-small cell lung cancer (NSCLC) cells have not been clarified. In this study, MTT assay and flow cytometry were conducted to investigate the effect of PG on proliferation and apoptosis of NSCLC cells in vitro, respectively. A xenograft model of A549 cell was established in nude mice to validate the in vitro findings. Western blot were performed to measure the expression of molecules involved in AMPK/ERK/NF-κB pathway. Results suggested that PG (50 or 100 µM) was significantly cytotoxic to A549 cells and SPC-A1 cells in vitro. PG treatment also inhibited the tumor growth of NSCLC cell mouse xenografts in vivo. These anti-proliferative and pro-apoptosis effects of PG were found to be regulated by the AMPK/ERK/NF-κB pathway. Consequently, PG suppressed proliferation and induced cell apoptosis in NSCLC cells. In conclusions, PG regulates AMPK/ERK/NF-κB axis in NSCLC cells, thereby inhibiting the proliferation and promoting the apoptosis of NSCLC cells.