Targeting of the respiratory chain by toxicants: beyond the toxicities to mitochondrial morphology

The mitochondrial link: Phthalate exposure and cardiovascular disease

Phthalates' pervasive presence in everyday life poses concern as they have been revealed to induce perturbing health defects. Utilized as a plasticizer, phthalates are riddled throughout many common consumer products including personal care products, food packaging, home furnishings, and medical supplies. Phthalates permeate into the environment by leaching out of these products which can subsequently be taken up by the human body. It is previously established that a connection exists between phthalate exposure and cardiovascular disease (CVD) development; however, the specific mitochondrial link in this scenario has not yet been described. Prior studies have indicated that one possible mechanism for how phthalates exert their effects is through mitochondrial dysfunction. By disturbing mitochondrial structure, function, and signaling, phthalates can contribute to the development of the foremost cause of death worldwide, CVD. This review will examine the potential link among phthalates and their effects on the mitochondria, permissive of CVD development.

Evaluation of in vitro effects of ifosfamide drug on mitochondrial functions using isolated mitochondria obtained from vital organs

Mitochondrial toxicity has been shown to contribute to a variety of organ toxicities such as, brain, heart, kidney, and liver. Ifosfamide (IFO) as an anticancer drug, is associated with increased risk of neurotoxicity, cardiotoxicity nephrotoxicity, hepatotoxicity, and hemorrhagic cystitis. The aim of this study was to evaluate the direct effect of IFO on isolated mitochondria obtained from the rat brain, heart, kidney, and liver. Mitochondria were isolated with mechanical lysis and differential centrifugation from different organs and treated with various concentrations of IFO. Using biochemical and flowcytometry assays, we evaluated mitochondrial succinate dehydrogenase (SDH) activity, mitochondrial swelling, lipid peroxidation, reactive oxygen species (ROS) production, and mitochondrial membrane potential (MMP). Our data showed that IFO did not cause deleterious alterations in mitochondrial functions, mitochondrial swelling, lipid peroxidation ROS formation, and MMP collapse in mitochondria isolated from brain, heart, kidney, and liver. Altogether, the data showed that IFO is not directly toxic in mitochondria isolated from brain, heart, kidney, and liver. This study proved that mitochondria alone does not play the main role in the toxicity of IFO, and suggests to reduce the toxicity of this drug, other pathways resulting in the production of toxic metabolites should be considered.

Ferritinophagy Mediated by Oxidative Stress-Driven Mitochondrial Damage Is Involved in the Polystyrene Nanoparticles-Induced Ferroptosis of Lung Injury

Nanoplastics are a common type of contaminant in the air. However, no investigations have focused on the toxic mechanism of lung injury induced by nanoplastic exposure. In the present study, polystyrene nanoplastics (PS-NPs) caused ferroptosis in lung epithelial cells, which could be alleviated by ferrostatin-1, deferoxamine, and N-acetylcysteine. Further investigation found that PS-NPs disturbed mitochondrial structure and function and triggered autophagy. Mechanistically, oxidative stress-derived mitochondrial damage contributed to ferroptosis, and autophagy-dependent ferritinophagy was a pivotal intermediate link, resulting in ferritin degradation and iron ion release. Furthermore, inhibition of ferroptosis using ferrostatin-1 alleviated pulmonary and systemic toxicity to reverse the mouse lung injury induced by PS-NPs inhalation. Most importantly, the lung-on-a-chip was further used to clarify the role of ferroptosis in the PS-NPs-induced lung injury by visualizing the ferroptosis, oxidative stress, and alveolar-capillary barrier dysfunction at the organ level. In summary, our study indicated that ferroptosis was an important mechanism for nanoplastics-induced lung injury through different lung cells, mouse inhalation models, and three-dimensional-based lung-on-a-chip, providing an insightful reference for pulmonary toxicity assessment of nanoplastics.

Heme oxygenase-1: A potential therapeutic target for improving skeletal muscle atrophy

Skeletal muscle atrophy is a common muscle disease that is directly caused by an imbalance in protein synthesis and degradation. At the histological level, it is mainly characterized by a reduction in muscle mass and fiber cross-sectional area (CSA). Patients with skeletal muscle atrophy present with reduced motor ability, easy fatigue, and poor life quality. Heme oxygenase-1 (HO-1) is an inducible enzyme that catalyzes the degradation of heme and has attracted much attention for its anti-oxidation effects. In addition, there is growing evidence that HO-1 plays an important role in anti-inflammatory, anti-apoptosis, pro-angiogenesis, and maintaining skeletal muscle homeostasis, making it a potential therapeutic target for improving skeletal muscle atrophy. Here, we review the pathogenesis of skeletal muscle atrophy, the biology of HO-1 and its regulation, and the biological function of HO-1 in skeletal muscle homeostasis, with a specific focus on the role of HO-1 in skeletal muscle atrophy, aiming to observe the therapeutic potential of HO-1 for skeletal muscle atrophy.

Cytosolic Release of Mitochondrial DNA and Associated cGAS Signaling Mediates Radiation-Induced Hematopoietic Injury of Mice

Mitochondrion is an important organelle of eukaryotic cells and a critical target of ionizing radiation (IR) outside the nucleus. The biological significance and mechanism of the non-target effect originating from mitochondria have received much attention in the field of radiation biology and protection. In this study, we investigated the effect, role, and radioprotective significance of cytosolic mitochondrial DNA (mtDNA) and its associated cGAS signaling on hematopoietic injury induced by IR in vitro culture cells and in vivo total body irradiated mice in this study. The results demonstrated that γ-ray exposure increases the release of mtDNA into the cytosol to activate cGAS signaling pathway, and the voltage-dependent anion channel (VDAC) may contribute to IR-induced mtDNA release. VDAC1 inhibitor DIDS and cGAS synthetase inhibitor can alleviate bone marrow injury and ameliorate hematopoietic suppression induced by IR via protecting hematopoietic stem cells and adjusting subtype distribution of bone marrow cells, such as attenuating the increase of the F4/80⁺ macrophage proportion in bone marrow cells. The present study provides a new mechanistic explanation for the radiation non-target effect and an alternative technical strategy for the prevention and treatment of hematopoietic acute radiation syndrome.

Flame Retardants-Mediated Interferon Signaling in the Pathogenesis of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a growing concern worldwide, affecting 25% of the global population. NAFLD is a multifactorial disease with a broad spectrum of pathology includes steatosis, which gradually progresses to a more severe condition such as nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and eventually leads to hepatic cancer. Several risk factors, including exposure to environmental toxicants, are involved in the development and progression of NAFLD. Environmental factors may promote the development and progression of NAFLD by various biological alterations, including mitochondrial dysfunction, reactive oxygen species production, nuclear receptors dysregulation, and interference in inflammatory and immune-mediated signaling. Moreover, environmental contaminants can influence immune responses by impairing the immune system’s components and, ultimately, disease susceptibility. Flame retardants (FRs) are anthropogenic chemicals or mixtures that are being used to inhibit or delay the spread of fire. FRs have been employed in several household and outdoor products; therefore, human exposure is unavoidable. In this review, we summarized the potential mechanisms of FRs-associated immune and inflammatory signaling and their possible contribution to the development and progression of NAFLD, with an emphasis on FRs-mediated interferon signaling. Knowledge gaps are identified, and emerging pharmacotherapeutic molecules targeting the immune and inflammatory signaling for NAFLD are also discussed.

BECN1 promotes radiation-induced G2/M arrest through regulation CDK1 activity: a potential role for autophagy in G2/M checkpoint

Authophagy and G2/M arrest are two important mechanistic responses of cells to ionizing radiation (IR), in particular the IR-induced fibrosis. However, what interplayer and how it links the autophagy and the G2/M arrest remains elusive. Here, we demonstrate that the autophagy-related protein BECN1 plays a critical role in ionizing radiation-induced G2/M arrest. The treatment of cells with autophagy inhibitor 3-methyladenine (3-MA) at 0-12 h but not 12 h postirradiation significantly sensitized them to IR, indicating a radio-protective role of autophagy in the early response of cells to radiation. 3-MA and BECN1 disruption inactivated the G2/M checkpoint following IR by abrogating the IR-induced phosphorylation of phosphatase CDC25C and its target CDK1, a key mediator of the G2/M transition in coordination with CCNB1. Irradiation increased the nuclear translocation of BECN1, and this process was inhibited by 3-MA. We confirmed that BECN1 interacts with CDC25C and CHK2, and which is mediated the amino acids 89-155 and 151-224 of BECN1, respectively. Importantly, BECN1 deficiency disrupted the interaction of CHK2 with CDC25C and the dissociation of CDC25C from CDK1 in response to irradiation, resulting in the dephosphorylation of CDK1 and overexpression of CDK1. In summary, IR induces the translocation of BECN1 to the nucleus, where it mediates the interaction between CDC25C and CHK2, resulting in the phosphorylation of CDC25C and its dissociation from CDK1. Consequently, the mitosis-promoting complex CDK1/CCNB1 is inactivated, resulting in the arrest of cells at the G2/M transition. Our findings demonstrated that BECN1 plays a role in promotion of radiation-induced G2/M arrest through regulation of CDK1 activity. Whether such functions of BECN1 in G2/M arrest is dependent or independent on its autophagy-related roles is necessary to further identify.

Radiation Exposure Associated With Computed Tomography in Childhood and the Subsequent Risk of Cancer: A Meta-Analysis of Cohort Studies

Background:

Computed tomography (CT) is used worldwide; however, recent studies suggest that CT radiation exposure during childhood may be a risk factor for cancer, although the data are inconsistent.

Methods:

A comprehensive search of electronic databases including PubMed, SpringerLink, Embase, Cochrane Library, Elsevier/ScienceDirect, Medline, Orbis, and Web of Science databases from January 1990 to November 2018 for observational epidemiologic studies reporting associations between radiation exposure from CT in childhood and the subsequent risk of cancer was conducted. A linear model was used to explore the dose–response relationship.

Results:

Seven studies with 1180 987 children enrolled were included. The risk of later cancer was 1.32-fold higher for children exposed to CT than those without exposure. Compared to those not exposed to pediatric CT, the relative risk (RRs) were larger for the higher doses but with wider CIs (RR for 5-10 mGy: 0.90, 95% CI: 0.69-1.12; RR for 10-15 mGy: 1.02, 95% CI: 0.86-1.18; RR for >15 mGy: 1.13, 95% CI: 0.97-1.30), the leukemia risk was higher in exposed children (RR: 1.23, 95% CI: 1.10-1.36), and brain cancer risk was higher in exposed children (RR: 1.54, 95% CI: 0.84-2.45).

Conclusions:

Our analysis suggested that radiation exposure from CT during childhood is associated with a subsequently elevated risk of cancer. However, caution is needed when interpreting these results because of the heterogeneity among the studies. The findings should be confirmed in further studies with longer follow-up periods.

Suppression of LINC00460 mediated the sensitization of HCT116 cells to ionizing radiation by inhibiting epithelial-mesenchymal transition

Radiation resistance is the most common challenge for improving radiotherapy. The mechanisms underlying the development of radioresistance remain poorly understood. This study aims to explore the role of LINC00460 in ionizing radiation-induced radioresistance as well as the mechanisms by which LINC00460 is regulated by radiation exposure. The expression of LINC00460 was measured. Cell proliferation and colony formation were measured in HCT116 cells after treatment by radiation. The development of epithelial-mesenchymal transition (EMT) was determined with or without knockdown LINC00460 expression using western blot analysis. Transcription activity was determined using a series of LINC00460-promoter luciferase reporter gene vectors. LINC00460 expression was significantly higher in HCT116 cells, relative to other cell types, with LINC00460 expression significantly affecting HCT116 cell proliferation. Suppression of LINC00460 inhibits EMT development in HCT116 cells via regulation of ZEB1 expression. Furthermore, LINC00460 expression was induced by irradiation via the activation of c-jun transcription factor-binding element located on the LINC00460 promoter. LINC00460 was shown to play a crucial role in EMT-associated progression of colorectal cancer, indicating that LINC00460 may be an indicator or new potential therapeutic target for colorectal cancer radiosensitization.

Associations between ambient air pollution and daily incidence of pediatric hand, foot and mouth disease in Ningbo, 2014-2016: a distributed lag nonlinear model

Hand, foot and mouth disease (HFMD) has high prevalence around the world, with serious consequences for children. Due to the long survival period of HFMD virus in ambient air, air pollutants may play a critical role in HFMD epidemics. We collected data on daily cases of HFMD among children aged 0–14 years in Ningbo City between 2014 and 2016. Distributed lag nonlinear models were used to assess the effects of particulate matter (PM_2.5), sulphur dioxide (SO₂), nitrogen dioxide (NO₂) and ozone (O₃) on the daily incidence of HFMD among children, with analyses stratified by gender and age. Compared with moderate levels of air pollution, high SO₂ levels had a relative risk (RR) of 2.32 (95% CI 1.42–3.79) and high NO₂ levels had a RR of 2.01 (95% CI 1.22–3.31). The RR of O₃ was 2.12 (95% CI 1.47–3.05) and that of PM_2.5 was 0.77 (95% CI 0.64–0.92) at moderate levels of air pollution. Specifically, high levels of SO₂ and NO₂ had RRs of 2.39 (95% CI 1.44–3.96) and 2.02 (95% CI 1.21–3.39), respectively, among 0–4-year-old children, while high O₃ had an RR of 2.31 (95% CI 1.09–4.89) among 5–14-year-old children. Our findings suggest significant associations of high SO₂ and NO₂ levels and moderate O₃ levels in HFMD epidemics, and also indicate that air pollution causes lagged effects on HFMD epidemics. Our study provides practical and useful data for targeted prevention and control of HMFD based on environmental evidence.

A novel miR-0308-3p revealed by miRNA-seq of HBV-positive hepatocellular carcinoma suppresses cell proliferation and promotes G1/S arrest by targeting double CDK6/Cyclin D1 genes

Background

Persistent infection with hepatitis B virus (HBV) accounts for the majority of hepatocellular carcinoma (HCC), but the molecular mechanisms underlying liver carcinogenesis are still not completely understood. Increasing evidence demonstrates that microRNAs (miRNAs) play significant functional roles in virus–host interactions. The aim of this study was to explore differentially expressed miRNA profiles and investigate the molecular mechanism of miR-0308-3p in HBV-positive HCC carcinogenesis.

Methods

High-throughput sequencing was used to detect novel miRNAs in three samples of HBV-positive HCC tissue compared to matched HBV-negative HCC tissue. The Cancer Genome Atlas (TCGA) database was used to mine miRNAs related to HBV-positive HCC. Bioinformatics analyses were conducted to predict the miRNAs’ possible biological and pathway regulatory functions. Quantitative polymerase chain reaction (qPCR) was then applied to evaluate the expression levels of randomly selected miRNAs. CCK-8 was used to measure cell proliferation and cell cycles were analyzed using flow cytometry. A dual luciferase reporter gene assay was used to confirm the downstream targets of miR-0308-3p.

Results

In total, there were 34 overlapping miRNAs in both our miRNA-seq data and the TCGA database. We found two overlapping miRNAs in both the HBV-positive HCC samples and the TCGA database, and 205 novel pre-miRNA sequences were predicted. miR-522 and miR-523 were markedly overexpressed in HBV-positive HCC and were associated with a significantly poorer long-term prognosis (miR-522, HR 2.19, 95% CI 1.33–3.6, p = 0.0015; miR-523HR 1.5, 95% CI 1–2.44, p = 0.0047). Of note, we found that the novel miR-0308-3p was markedly downregulated in HBV-positive HCC samples and HCC cancer cell lines compared with HBV-negative HCC samples and adjacent normal hepatic tissue. Moreover, elevated expression of miR-0308-3p was found to inhibit proliferation of cancer cells by promoting G1/S cell cycle arrest but did not influence the apoptosis of cancer cells. A dual luciferase reporter activity assay identified that miR-0308-3p acted directly on the target sequence of the CDK6 and Cyclin D1 mRNA 3ʹUTR to suppress CDK6 and Cyclin D1 expression.

Conclusions

MiR-0308-3p upregulation dramatically suppressed HCC cell proliferation and induced G1/S cell cycle arrest by directly targeting CDK6/Cyclin D1. These findings reveal a novel molecular mechanism for activation of G1/S arrest in HCC and may prove clinically useful for developing new therapeutic targets.

Mitochondrial toxicity of nanomaterials

In recent years, nanomaterials have been widely applied in electronics, food, biomedicine and other fields, resulting in increased human exposure and consequent research focus on their biological and toxic effects. Mitochondria, the main target organelle for nanomaterials (NM), play a critical role in their toxic activities. Several studies to date have shown that nanomaterials cause alterations in mitochondrial morphology, mitochondrial membrane potential, opening of the mitochondrial permeability transition pore (MPTP) and mitochondrial respiratory function, and promote cytochrome C release. An earlier mitochondrial toxicity study of NMs additionally reported induction of mitochondrial dynamic changes. Here, we have reviewed the mitochondrial toxicity of NMs and provided a scientific basis for the contribution of mitochondria to the toxicological effects of different NMs along with approaches to reduce mitochondrial and, consequently, overall toxicity of NMs.

Vitamin D, gut microbiota, and radiation-related resistance: a love-hate triangle

Radiation resistance is a serious issue in radiotherapy. Increasing evidence indicates that the human gut microbiome plays a role in the development of radiation resistance. Vitamin D is an important supplement for cancer patients treated with radiotherapy. Against this background, this paper reviewed research regarding the associations among vitamin D, microbiota dysbiosis, and radiation resistance. A hypothesis is developed to describe the relationships among vitamin D, the gut microbiota, and radiotherapy outcomes. Radiotherapy changes the composition of the gut microbiota, which in turn influence the serum level of vitamin D, and its distribution and metabolism in the body. Alteration of vitamin D level influences the patient response to radiotherapy, where the underlying mechanisms may be associated with the intestinal microenvironment, immune molecules in the intestines, gut microbiome metabolites, and signaling pathways associated with vitamin D receptors. Our understanding of the contribution of vitamin D and the gut microbiota to radiotherapy outcomes has been increasing gradually. A better understanding of the relationships among vitamin D, the gut microbiota, and radiotherapy outcomes will shed more light on radiation resistance, and also promote the development of new strategies for overcoming it, thus addressing an important challenge associated with the currently available radiotherapy modalities for cancer patients.

Effects of moderate red wine on cardiovascular risk factors in diabetics: a systematic review and meta-analysis of randomized controlled trials

Background: Diabetes mellitus is of major public health concerns; its incidence is continuously increasing. Diabetes mellitus is associated with a high risk of cardiovascular complications such as hypertension. Red wine has been reported to reduce cardiovascular risk factors. We quantified the effects of red wine on cardiovascular factors. Methods: We retrieved English-language articles published from January 1990 to April 2019. Cardiovascular risk factors were compared using means with 95% confidence intervals (95% CIs). Results: We identified five eligible randomized controlled trials. Diabetic patients who drank red wine exhibited significantly reduced systolic blood pressure (BP) (mean difference [MD] -1.33, 95% CI -1.81, -0.85) and diastolic BP (MD -1.31, 95% CI -1.80, -0.83) than those who did not. Compared to the observations for diabetics who did not drink red wine, the high-density lipoprotein (HDL) level was significantly higher in red wine drinkers (MD -0.24, 95% CI -0.39, -0.09). However, red wine had no effect on the body mass index (BMI) (MD -0.27, 95% CI -1.80, 1.25), the total cholesterol level (MD 0.13, 95% CI -0.17, 0.44), or the low-density lipoprotein (LDL) level (MD 0.08, 95% CI -0.21, 0.37). Conclusions: Red wine consumption significantly lowered BP and increased the HDL level in diabetics. Red wine had no significant effect on BMI or cholesterol and LDL levels. Given the heterogeneity of the studied populations and the lack of standardization and completeness across the published studies, caution is required while interpreting these findings.

Analysis of lncRNA and mRNA Transcriptomes Expression in Thyroid Cancer Tissues Among Patients With Exposure of Medical Occupational Radiation

Background:

Occupational exposure of radiation among medical radiation workers contributes to the subsequent increased risk of thyroid cancer. Long noncoding RNAs (lncRNAs) are emerging as important regulators of cancer biology. However, little is known about lncRNA expression in thyroid cancer tissues from patients who are exposed to medical occupational radiation. The purpose of this study is to reveal the transcriptomes difference between thyroid cancer tissues and adjacent nonneoplastic thyroid tissues.

Methods:

Microarray technology was used in this study. Quantitative reverse transcription polymerase chain reaction was adopted to verify 6 differentially expressed lncRNAs. Gene ontology and pathway analyses were performed using standard enrichment computational methods. Potential target genes of the differentially expressed lncRNAs were predicted with 2 independent algorithms.

Results:

A total of 23 lncRNA and messenger RNA transcripts were found differentially expressed in the thyroid cancer tissues (fold change ≥2.0, P < .05). This differential lncRNA expression may affect many pathways, including those involved in cysteine and methionine metabolism, Huntington disease, propanoate metabolism, and carcinogenesis.

Conclusions:

Our study provides a transcriptome-wide screening and analysis of the lncRNA expression profile in thyroid cancer tissues from patients with medical occupational radiation exposure and lays the foundation for further investigation of lncRNAs related to thyroid cancer development and carcinogenic risk of medical occupational radiation exposure.

Impact of Low-dose Ionising Radiation on the Composition of the Gut Microbiota of Mice

BACKGROUND

Although the importance of the gut microbiota in the maintenance of human health has been well established, little is known about the impact of low-dose ionising radiation (exposure to a dose of less than 0.5 Gy of low linear energy transfer radiation such as γ- or X-rays [LDR]) on the composition and functional role of the gut microbiota. The aim of the present study was to investigate and compare the composition of the gut microbiota in mice exposed to LDR.

METHODS AND MATERIALS

Male BALB/c mice were exposed to low-dose Co60 radiation. Faecal samples taken prior to and after irradiation were used for high-throughput sequencing of 16S rRNA gene sequence amplicons.

RESULTS

We observed substantial changes in the composition of the gut microbiota, including alpha diversity and beta diversity, in mice exposed to LDR compared to the non-radiated control group. Moreover, at the genus level, the abundance of Clostridium, Helicobacter and Oscilibacter increased, and those of Bacteroides and Barnesiella decreased, in a time-dependent manner in the radiated groups compared to the non-radiated control group. The functional metabolic pathway analysis indicated that Bacteroides spp. and members of the other genera that were found are predicted to play roles in bacterial toxin production, DNA repair, and Type II diabetes. Furthermore, these alterations in the gut microbiota were accompanied by changes in the abundance of multiple metabolites, which were predicted to be involved in multiple signalling pathways, including glucagon, central carbon metabolism, and type II diabetes.

CONCLUSIONS

The possibility of microbiota-mediated pathophysiology resulting from LDR may be an as yet unrecognised hazard that merits further experimental examination. This study provides a conceptual and analytical foundation for further research into the chronic effects of LDR on human health, and points to potential novel targets for intervention to prevent the adverse effects of radiation.

Double-edged effects of noncoding RNAs in responses to environmental genotoxic insults: Perspectives with regards to molecule-ecology network

Numerous recent studies have underlined the crucial players of noncoding RNAs (ncRNAs), i.e., microRNAs(miRNAs), long noncoding RNAs(lncRNAs) and circle RNAs(circRNAs) participating in genotoxic responses induced by a wide variety of environmental genotoxicants consistently. Genotoxic-derived ncRNAs provide us a new epigenetic molecular-ecological network (MEN) insights into the underlying mechanisms regarding genotoxicant exposure and genotoxic effects, which can modify ncRNAs to render them "genotoxic" and inheritable, thus potentially leading to disease risk via epigenetic changes. In fact, the spatial structures of ncRNAs, particularly of secondary and three-dimensional structures, diverse environmental genotoxicants as well as RNA splicing and editing forma dynamic pool of ncRNAs, which constructs a MEN in cells together with their enormous targets and interactions, making biological functions more complicated. We nonetheless suggest that ncRNAs have both beneficial(positive) and harmful(negative) effects, i.e., are "double-edged" in regulating genotoxicant toxic responses. Understanding the "double-edged" effects of ncRNAs is of crucial importance for our further comprehension of the pathogenesis of human diseases induced by environmental toxicants and for the construction of novel prevention and therapy targets. Furthermore, the MEN formed by ncRNAs and their interactions each other as well as downstream targets in the cells is important for considering the active relationships between external agents (environmental toxicants) and inherent genomic ncRNAs, in terms of suppression or promotion (down- or upregulation), and engineered ncRNA therapies can suppress or promote the expression of inherent genomic ncRNAs that are targets of environmental toxicants. Moreover, the MEN would be expected to be would be applied to the mechanistic explanation and risk assessment at whole scene level in environmental genotoxicant exposure. As molecular biology evolves rapidly, the proposed MEN perspective will provide a clearer or more comprehensive holistic view.

Alterations in the gut microbiota of patients with silica-induced pulmonary fibrosis

Silicosis resulting from silica exposure is a global occupational disease characterized by severe pathological changes in progressive pulmonary fibrosis. Previous evidence has indicated that dysbiosis of the gut microbiota occurs after environmental dust exposure and is associated with certain diseases. The aims of this study are to elucidate the compositional and functional characteristics of the gut microbiota in early-stage silicosis and to understand their influence on pulmonary fibrosis. We investigated the gut microbial composition of fecal samples from 18 patients and 21 healthy subjects using 16S rRNA gene sequencing technology. Compared with the healthy subjects, reductions in the levels of Firmicutes and Actinobacteria were noted in patients with silicosis and progressive pulmonary fibrosis, as well as lower levels of Devosia, Clostridiales, AlloprevotellaandRikenellaceae_RC9. Lachnospiraceae and Lachnoclostridium levels were increased in patients with silicosis. GOC and KEGG analyses were used to predict that certain bacteria taxa play critical roles in the development of pulmonary fibrosis, including posttranslational modification, amino acid transport and metabolism, nucleotide transport and metabolism, and ribosomal structure and biogenesis. KEGG analysis showed that certain taxa participate in various roles including cancer, endocrine metabolism, immune system, signaling molecules and interaction, and transcription. Collectively, in this pilot study, microbiota changes have been represented in the gut of patients with silicosis. Although this change in gut microbiota have been represented, caution is needed when interpreting the findings since this is observational finding, not necessarily causative. More studies should be performed in the expanding population to be verified and more studies underlying biological mechanisms for better understanding the relationship between gut microbiota and development of pulmonary fibrosis in patients with silicosis.

Analysis of mRNA Expression Patterns in Peripheral Blood Cells of 3 Patients With Cancer After the First Fraction of 2 Gy Irradiation: An Integrated Case Report and Systematic Review

Background

Radiation therapy induces acute and chronic radiological toxicity, in particular hematological toxicity (HT). This study aimed to explore the mechanistic clue and potential predictors at the messenger RNA (mRNA) level.

Materials and Methods

Peripheral blood was collected from 3 patients with cervical cancer (CC), nasopharynx cancer (NC), and tongue cancer (TC) after the first 2 Gy fraction of radiotherapy (RT). High-throughput sequencing was used to assess mRNA profiles.

Results

Eleven genes, such as ALAS2(5-aminolevulinate synthase), SLC4A1(solute carrier family 4 member 1), HBG2(hemoglobin subunit gamma 2), TNFAIP3 (TNF α-induced protein 3), PER1 (period circadian clock 1), CCDC136 (coiled-coil domain containing 136), C9orf84 (chromosome 9 open reading frame 84), IL1B (interleukin 1β), FOSB (FosB protooncogene), NR4A2 (nuclear receptor subfamily 4), PARP15 (polymerase family member 15), had overlapping expression changes in all 3 cancers of which 3 (ALAS2, FOSB, and HBG2) are suggested as potential predictors for the early diagnosis of HT after RT.

Conclusions

ALAS2, FOSB, and HBG2 may be useful predictors of HT in patients after RT. Eleven overlapping expression mRNAs among 3 cancers might be potential predictors for early diagnosis of radiation toxicity in patients.

Integrated Analysis of lncRNA and mRNA Transcriptomes Reveals New Regulators of Ubiquitination and the Immune Response in Silica-Induced Pulmonary Fibrosis

Objectives

As an epigenetic player, long noncoding RNAs (LncRNAs) have been reported to participate in multiple biological processes; however, their biological functions in silica-induced pulmonary fibrosis (SIPF) occurrence and development remain incompletely understood.

Methods

Five case/control pairs were used to perform integrated transcriptomes analysis of lncRNA and mRNA. Prediction of lncRNA and mRNA functions was aided by the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Additionally, we constructed a coexpression network of lncRNAs and mRNAs to identify targets of regulation.

Results

In total, 1069 differentially expressed mRNAs and 366 lncRNAs were identified with the changes more than 2 times (p<0.05), of which 351 downregulated mRNA and 31 downregulated lncRNA were <0.5 (p<0.05) and those of 718 upregulated mRNAs and 335 upregulated lncRNA were >2 (p<0.05). The levels of 10 lncRNAs were measured via qRT-PCR; the results were consistent with the microarray data. Four genes named of FEM1B, TRIM39, TRIM32, and KLHL15 were enriched significantly with ubiquitination and immune response. Cytokine-cytokine receptor interaction was the most significantly enriched KEGG pathway in both mRNAs and lncRNAs. The coexpression network revealed that a single lncRNA can interact with multiple mRNAs, and vice versa.

Conclusions

lncRNA and mRNA expression were aberrant in patients with SIPF compared to controls, indicating that differentially expressed lncRNAs and mRNAs may play critical roles in SIPF development. Our study affords new insights into the molecular mechanisms of SIPF and identifies potential biomarkers and targets for SIPF diagnosis and treatment.