Staphylococcus aureus acquires resistance to glycopeptide antibiotic vancomycin via CXCL10.

BACKGROUND: Glycopeptide antibiotic vancomycin is a bactericidal antibiotic available for the infection to Staphylococcus aureus (SA), however, SA has a strong adaptive capacity and thereby acquires resistance to vancomycin. This study aims to illuminate the possible molecular mechanism of vancomycin resistance of SA based on the 16S rRNA sequencing data and microarray profiling data. METHODS: 16S rRNA sequencing data of control samples and urinary tract infection samples were retrieved from the EMBL-EBI (European Molecular Biology Laboratory - European Bioinformatics Institute) database. Correlation of gut flora and clinical indicators was evaluated. The possible targets regulated by SA were predicted by microarray profiling and subjected to KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis. CXCL10 gene knockout and overexpression were introduced to evaluate the effect of CXCL10 on the virulence of SA and the resistance to vancomycin. SA strains were co-cultured with urethral epithelial cells in vitro. The presence of SA virulence factors was detected using PCR. Biofilm formation of SA strains was assessed using the microtiter plate method. Furthermore, the antibiotic sensitivity of SA strains was evaluated through vancomycin testing. RESULTS: Gut flora and its species abundance had significant difference between urinary tract infection and control samples. SA was significantly differentially expressed in urinary tract infection samples. Resistance of SA to vancomycin mainly linked to the D-alanine metabolism pathway. SA may participate in the occurrence of urinary tract infection by upregulating CXCL10. In addition, CXCL10 mainly affected the SA resistance to vancomycin through the TLR signaling pathway. In vitro experimental results further confirmed that the overexpression of CXCL10 in SA increased SA virulence and decreased its susceptibility to vancomycin. In vitro experimental validation demonstrated that the knockout of CXCL10 in urethral epithelial cells enhanced the sensitivity of Staphylococcus aureus (SA) to vancomycin. CONCLUSION: SA upregulates the expression of CXCL10 in urethral epithelial cells, thereby activating the TLR signaling pathway and promoting resistance to glycopeptide antibiotics in SA.

PEI, a new transfection method, augments the inhibitory effect of RBM5 on prostate cancer.

PEI is a cationic polymer, serving as a non-viral transfection carrier grounded in nanotechnology that enhances transfection efficiency via the proton sponge effect. RBM5 is an RNA-binding protein that can inhibit tumor development. This study involved the transfection of RBM5 in prostate cancer cells with PEI, Lipo2000, and their combination. Transwell and wound healing assays were used to observe invasion and migration of prostate cancer cells and flow cytometry was used to observe the apoptosis. Detect the expression of invasion and migration-related protein MMP9 through western blotting experiment. An activity detection kit was used to detect the activity of apoptotic protein caspase-3. We found that there was no significant difference in transfection efficiency when PEI and Lipo2000 were used alone but it significantly improved when they are combined. RBM5 reduced invasion, migration, and proliferation of prostate cancer and enhanced apoptosis. MMP9 expression was reduced, and the activity of caspase-3 was increased. PEI transfection could improve the inhibition of RBM5 on tumors more than Lipo2000. The inhibitory effect is more obvious when the two are used together. RBM5 transfected with PEI can amplify its inhibitory effect on prostate cancer, and this effect is more evident when combined with Lipo2000.

RBM10 recruits METTL3 to induce N6-methyladenosine-MALAT1-dependent modification, inhibiting the invasion and migration of NSCLC.

AIMS: Previous studies have shown that RNA binding motif 10 (RBM10) is a potential tumor suppressor protein that can inhibit proliferation and promote apoptosis of non-small cell lung cancer (NSCLC). Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) plays an important role in promoting the development of lung cancer. Inhibiting its m6A methylation can effectively inhibit the invasion and metastasis of lung cancer. There is concern that RBM10 could affect MALAT1 m6A methylation for the invasion and migration of NSCLC. MAIN METHODS AND FINDINGS: Transwell and wound healing assays showed that RBM10 significantly inhibited the invasion and migration of NSCLC. CLIP-Seq showed that among all RBM10 binding RNAs, MALAT1 had the highest binding peak among all non-coding RNAs. RNA immunoprecipitation verified the direct combination of RBM10 and MALAT1. The rescue experiment confirmed that RBM10 affected the phosphorylation of the PI3K/AKT/mTOR pathway protein as well as the invasion and migration ability by regulating MALAT1. MeRIP-qPCR confirmed that RBM10 could inhibit the MALAT1 m6A methylation level by recruiting Methyltransferase Like 3 (METTL3). SIGNIFICANCE: The study suggests that RBM10, as an RNA-binding protein, may inhibit the m6A methylation of MALAT1 by recruiting METTL3 and affecting phosphorylation of the downstream PI3K/AKT/mTOR pathway by binding and regulating MALAT1, ultimately affecting the invasion and migration of NSCLC.

Clinical identification of expressed proteins in adrenal medullary hyperplasia detected with hypertension.

Background: Hypertension remains a challenging public health problem worldwide, and adrenal gland-related diseases are one class of the major causes for secondary hypertension. Among them, one relatively rare pattern is adrenal hyperplastic hypertension caused by adrenal medullary hyperplasia (AMH), leading to excessive secretion of autonomic catecholamine. Given that the pathological changes of adrenal medulla are not well correlated to the onset and even severity of secondary hypertension, the molecular basis why some AMH patients are accompanied with hypertension remains unclear and is worth exploring. Aims: For this reason, this study aims at investigating differentially expressed proteins in clinical AMH tissue, with special focus on the potential contribution of these differentially expressed proteins to AMH development, in order to have a better understanding of mechanisms how AMH leads to secondary hypertension to some extent. Methods and results: To this end, AMH specimens were successfully obtained and verified through computed tomography (CT) and haematoxylin-eosin (HE) staining. Proteomic analyses of AMH and control tissues revealed 782 kinds of differentially expressed proteins. Compared with the control tissue, there were 357 types of upregulated proteins and 425 types of downregulated proteins detected in AMH tissue. Of interest, these differentially expressed proteins were significantly enriched in 60 gene ontology terms (P < 0.05), including 28 biological process terms, 14 molecular function terms, and 18 cellular component terms. Pathway analysis further indicated that 306 proteins exert their functions in at least one Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Western blotting showed enhanced expression of phenylethanolamine N- methyltransferase (PNMT), myelin protein zero (MPZ), and Ras-related protein Rab-3C (RAB3C), and reduced expression of cluster of differentiation 36 (CD36) observed in AMH tissue in comparison with controls. Conclusions: Clinical AMH specimens display a different proteomic profile compared to control tissue. Of note, PNMT, MPZ, RAB3C, and CD36 are found to differentially expressed and can be potential targets for AMH, providing a theoretical basis for mechanistic exploration of AMH along with hypertension.

Extracellular vesicles participate in the pathogenesis of sepsis.

Sepsis is one of the leading causes of mortality worldwide and is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. The early diagnosis and effective treatment of sepsis still face challenges due to its rapid progression, dynamic changes, and strong heterogeneity among different individuals. To develop novel strategies to control sepsis, a better understanding of the complex mechanisms of sepsis is vital. Extracellular vesicles (EVs) are membrane vesicles released from cells through different mechanisms. In the disease state, the number of EVs produced by activated or apoptotic cells and the cargoes they carry were altered. They regulated the function of local or distant host cells in autocrine or paracrine ways. Current studies have found that EVs are involved in the occurrence and development of sepsis through multiple pathways. In this review, we focus on changes in the cargoes of EVs in sepsis, the regulatory roles of EVs derived from host cells and bacteria, and how EVs are involved in multiple pathological processes and organ dysfunction in sepsis. Overall, EVs have great application prospects in sepsis, such as early diagnosis of sepsis, dynamic monitoring of disease, precise therapeutic targets, and prevention of sepsis as a vaccine platform.

RBM10 regulates alternative splicing of lncRNA Neat1 to inhibit the invasion and metastasis of NSCLC.

BACKGROUND: Non-small cell lung cancer (NSCLC) accounts for more than 85% of the total cases with lung cancer. NSCLC is characterized by easy metastasis, which often spreads to bones, brains and livers. RNA-binding motif protein 10 (RBM10) is an alternative splicing (AS) regulator frequently mutated in NSCLC. We found that there were multiple peak binding sites between RBM10 and long non-coding RNA nuclear enriched abundant transcript 1 (LncRNA Neat1) by crosslinking-immunprecipitation and high-throughput sequencing (Clip-Seq). LncRNA Neat1 plays an indispensable role in promoting cancer in a variety of tumors and produces two splicing variants: Neat1_1 and Neat1_2. This study aims to explore the mechanism of RBM10 and LncRNA Neat1 in invasion and metastasis of NSCLC. METHODS: Through histological and cytological experiments, we assessed the expression level of RBM10 protein expression. The interaction between RBM10 and Neat1 was evaluated via Clip-Seq and RNA immunoprecipitation assay. The effect of RBM10 on Neat1 and its splicing variants was identified by RT-qPCR. The effect of RBM10 and Neat1 on invasive and metastasis phenotypes of NSCLC was analyzed using transwell invasion assay and scratch test. Additionally, downstream signaling pathway of RBM10 were identified by immunofluorescence and western blot. RESULTS: RBM10 exhibited low levels of expression in NSCLC tissues and cells. RBM10 inhibited the invasion and metastasis of NSCLC and recruited Neat1 and Neat1_2. Overexpression of RBM10 simultaneously inhibited Neat1 and Neat1_2, and promoted the expression of Neat1_1. On the other hand, silencing RBM10 promoted Neat1 and Neat1_2, and inhibited the expression of Neat1_1. From this, we concluded that RBM10 regulated AS of Neat1, and the tumor-promoting effect of Neat1 was mainly attributed to Neat1_2. RBM10 had a negative correlation with Neat1_2. In addition, RBM10 upregulated the expression of PTEN and downregulated the phosphorylation of PI3K/AKT/mTOR through Neat1_2, which ultimately inhibited the invasion and metastasis of NSCLC. CONCLUSION: The RBM10 regulated AS of Neat1 to cause the imbalance of Neat1_1 and Neat1_2, and RBM10 suppressed the activation of the PTEN/PI3K/AKT/mTOR signal by downregulating Neat1_2, finally affected the invasion and metastasis of NSCLC.

Fertility problems in men carrying a translocation involved in breakpoints on chromosome 17p13: A retrospective, observational study.

Male infertility is a multifactorial reproductive disorder. The effect of genetic factors on male infertility has been the focus of research. Although a variety of genetic techniques are applied to male infertility in clinical practice, karyotype analysis remains a powerful and inexpensive technology. Reciprocal chromosomal translocation (RCT) is closely related to male infertility, but the clinical phenotypes of RCT carriers are varied, and the underlying pathological mechanism is unclear. Some studies suggest that RCT breakpoints disrupt the structure and function of important genes responsible for spermatogenesis. Several breakpoints of chromosome 17 are related to important genes, which can lead to spermatogenic failure. This study aimed to identify the clinical features of 3 men with translocation karyotypes involving breakpoints on chromosome 17p13. Semen analysis and cytogenetic analysis were performed with informed consent. Gene ontology analysis was performed for 60 pathogenic genes on chromosome band 17p13. Cytogenetic analysis showed that the karyotypes were 46, XY, t(6;17) (p21;p13), 46,XY,t(10;17)(q11.2;p13), and 46, XY, t(17;20) (p13;q13), respectively. Relevant studies and genes on breakpoints on chromosome 17p13 were searched for using PubMed. Fourteen reported cases of the same karyotype were reviewed. The results suggest that although chromosome 17 is closely related to spermatogenic failure, the clinical phenotypes of RCT carriers with involvement of 17p13 breakpoints are varied. The important genes involved in the breakpoint were analyzed. The results of molecular functions suggested that these targets genes on chromosome band 17p13 were mostly involved in microfilament motor activity, ATPase activity. These results suggested that the translocation chromosome and breakpoint analysis should be considered in the clinical assessment of the patients. Physicians should be aware of these in genetic counseling. These breakpoints and the function of related genes require further study.

RBM10 Regulates Tumor Apoptosis, Proliferation, and Metastasis.

The RNA-binding motif protein 10 (RBM10) is involved in alternative splicing and modifies mRNA post-transcriptionally. RBM10 is abnormally expressed in the lung, breast, and colorectal cancer, female genital tumors, osteosarcoma, and other malignant tumors. It can inhibit proliferation, promote apoptosis, and inhibit invasion and metastasis. RBM10 has long been considered a tumor suppressor because it promotes apoptosis through the regulation of the MDM2-p53 negative feedback loop, Bcl-2, Bax, and other apoptotic proteins and inhibits proliferation through the Notch signaling and rap1a/Akt/CREB pathways. However, it has been recently demonstrated that RBM10 can also promote cancer. Given these different views, it is necessary to summarize the research progress of RBM10 in various fields to reasonably analyze the underlying molecular mechanisms, and provide new ideas and directions for the clinical research of RBM10 in various cancer types. In this review, we provide a new perspective on the reasons for these opposing effects on cancer biology, molecular mechanisms, research progress, and clinical value of RBM10.

Pericentric inversion in chromosome 1 and male infertility.

Pericentric inversion in chromosome 1 was thought to cause male infertility through spermatogenic impairment, regardless of the breakpoint position. However, carriers of pericentric inversion in chromosome 1 have been reported with normal fertility and familial transmission. Here, we report two cases of pericentric inversion in chromosome 1. One case was detected in utero via amniocentesis, and the other case was detected after the wife of the carrier experienced two spontaneous abortions within 5 years of marriage. Here, the effect of the breakpoint position of the inversion in chromosome 1 on male infertility is examined and compared with the published cases. The association between the breakpoint of pericentric inversion in chromosome 1 and spermatogenesis is also discussed. Overall, the results suggest that the breakpoint position deserves attention from physicians in genetic counseling as inversion carriers can produce offspring.

iTRAQ-Based Proteomics Reveals Potential Anti-Virulence Targets for ESBL-Producing Klebsiella pneumoniae.

PURPOSE: Treatment of infections with Klebsiella pneumoniae strains producing extended-spectrum beta-lactamases (ESBLs) is challenging due to the coexistence of multiple resistance mechanisms and the hypervirulent variant. Therefore, new targets or more effective treatment options aimed at ESBL-producing Klebsiella pneumoniae are urgently needed. MATERIALS AND METHODS: Here, we collected ESBL-producing and non-ESBL Klebsiella pneumoniae isolates and studied their differences from a proteomic point of view. RESULTS: We revealed treA, wza, gnd, rmlA, rmlC, rmlD, galE, aceE, and sucD as important virulence-related proteins in ESBL-producing Klebsiella pneumoniae, distinct from those in non-ESBL strains. CONCLUSION: Our findings provide plausible anti-virulence targets and suggest new therapeutic avenues against ESBL-producing Klebsiella pneumoniae.

Polydopamine-assisted PDGF-BB immobilization on PLGA fibrous substrate enhances wound healing via regulating anti-inflammatory and cytokine secretion.

Platelet-derived growth factor-bb (PDGF-BB) is a potent chemokine and mitogen for fibroblasts, keratinocytes, and vascular endothelium in the injured area, believed to be effective in wound healing. However, the short half-life of PDGF-BB and its rapid release from the wound surface limited its efficacy in vivo and vitro. To evaluate the wound healing effects of dorsal skin in SD rats with polydopamine-assisted immobilized PDGF-BB on PLGA nanofibrous substrate. First, the effects of pDA-coating and PDGF-BB immobilization on the morphology, compositions, and hydrophilicity of substrates were evaluated in details. Second, the wound healing effect of pDA/PLGA/PDGF-BB substrate was assessed in the dorsal skin of SD rats. Last, the cytokine analysis by ELISA method was employed to evaluate the advantages of pDA/PLGA/PDGF-BB substrate on anti-inflammatory, angiogenesis, and cellular proliferation. This method significantly improved the immobilization amount and stability of PDGF-BB on the substrate (p<0.01), further improved the hydrophilicity of substrates (p<0.05). Furthermore, the wound closure process was much more accelerated in the pDA/PLGA/PDGF-BB group (p<0.05). H&E and CD31 staining informed that the wound treated by pDA/PLGA/PDGF-BB substrate showed a high degree of regeneration and angiogenesis. The cytokine analysis showed that pDA significantly reduced the high level of inflammatory cytokines such as TNF-α (p<0.05). And the immobilized PDGF-BB significantly elevated the level of TGF-ß and VEGF (p<0.05). The pDA/PLGA/PDGF-BB substrate showed great therapeutic effect on wound healing compared with other control groups via regulating anti-inflammatory, angiogenesis, and cellular proliferation. Absolutely, this report offered an available novel method for skin regeneration.

Chromosome 1q21 translocation and spermatogenesis failure: Two case reports and review of the literature.

RATIONALE: For the carriers of chromosome reciprocal translocation, the reason why some are fertile and others are infertile remains unclear. Here, we describe 2 patients who are carriers of chromosome 1q21 translocation with azoospermia. PATIENT CONCERNS: A 29-year-old male and a 33-year-old male presented at the clinic with a diagnosis of infertility. DIAGNOSIS: Both patients with azoospermia were diagnosed with Routine semen analysis, cytogenetic diagnosis and detection of serum reproductive hormones. The karyotype results of 2 patients were 46,XY,t(1;17)(q21;q23) and 46,XY,t(1;10)(q21;p12), respectively. INTERVENTIONS: After genetic counseling and informed consent, 1 patient (Case 2) chose microsopic testicular sperm extraction (micro-TESE). OUTCOMES: After micro-TESE, no sperm was found for the patient. Finally, both patients chose clinical treatment through artificial insemination with donor sperm. LESSONS: These outcomes suggest that breakpoint at 1q21 should be paid attention by physician in genetic counseling, may harbor some genes associated with spermatogenesis, and deserves further be studied on the function of related genes.

ITRAQ-based proteomic analysis reveals possible target-related proteins in human adrenocortical adenomas.

BACKGROUND: Adrenocortical adenomas (ACAs) can lead to the autonomous secretion of aldosterone responsible for primary aldosteronism (PA), which is the most common form of secondary arterial hypertension. However, the authentic fundamental mechanisms underlying ACAs remain unclear. OBJECTIVE: Isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics and bioinformatics analyses from etiological studies of ACAs were performed to screen the differentially expressed proteins (DEPs) and investigate the relevant mechanisms of their occurrence and development. Results could help determine therapeutic targets of clinical significance. METHODS: In the present study, iTRAQ-based proteomics was applied to analyze ACA tissue samples from normal adrenal cortex tissues adjacent to the tumor. Using proteins extracted from a panel of four pairs of ACA samples, we identified some upregulated proteins and other downregulated proteins in all four pairs of ACA samples compared with adjacent normal tissue. Subsequently, we predicted protein-protein interaction networks of three DEPs to determine the authentic functional factors in ACA. RESULTS: A total of 753 DEPs were identified, including 347 upregulated and 406 downregulated proteins. The expression of three upregulated proteins (E2F3, KRT6A, and ALDH1A2) was validated by Western blot in 24 ACA samples. Our data suggested that some DEPs might be important hallmarks during the development of ACA. CONCLUSIONS: This study is the first proteomic research to investigate alterations in protein levels and affected pathways in ACA using the iTRAQ technique. Thus, this study not only provides a comprehensive dataset on overall protein changes but also sheds light on its potential molecular mechanism in human ACAs.

Efficacy and safety of glucocorticoids in the treatment of severe community-acquired pneumonia: A meta-analysis.

BACKGROUND: Recent clinical trials have shown that adjunctive glucocorticoids is associated with inhibiting excessive inflammatory response and modulating cytokines release offering several advantages over conventional therapy on relieving clinical symptoms, reducing mortality, and improving prognosis. However, given the severe complications triggered by glucocorticosteroid, whether similar benefits may be achieved by patients undergoing glucocorticosteroid intervention remains controversial. Our meta-analysis aimed to investigate the efficacy and safety of adjunctive glucocorticoids in the treatment of severe community acquired pneumonia. METHODS: A search of PubMed, EMBASE, Cochrane Library, EBASO, Medline, Google Scholar, Science Dicet, CBM, and CNKI databases was performed to analyze all relevant randomized controlled trials (RCTs) of corticosteroids in patients with severe community acquired pneumonia (CAP) up to January 2018. All-cause mortality, C-reactive protein (CRP) level, incidence of septic shock, and requirement of mechanical ventilation were selected as efficacy outcomes. Major adverse events involving super infection, upper gastrointestinal bleeding, and hyperglycemia were safety outcomes. Meta-analysis was conducted with RevMan 5.3 software. RESULTS: A total of 10 RCTs comprising 665 patients were included for analysis. Regarding efficacy outcomes, adjunctive corticosteroid seemed to be superior compared with conventional treatment in terms of all-cause mortality (relative risk [RR]: 0.47, 95% confidence interval [CI], 0.3-0.74, P = .001), CRP level on day 8 after administration (standard mean difference [SMD]: -0.8, 95% CI, -1.11 to -0.5, P < .001), incidence of septic shock (odds ratio [OR] 0.15, 95% CI, 0.07-0.29, P < .001) and requirement for mechanical ventilation (OR: 0.32, 95% CI, 0.20-0.52, P < .001). Meanwhile, we found that low dose (≤86 mg) (RR: 0.41, 95% CI, 0.21-0.82, P = .01) and prolonged (>5 days) (RR: 0.35, 95% CI, 0.15-0.81, P = .01) use of corticosteroids in dosage modus of a maintenance dose after a bolus (RR: 0.28, 95% CI, 0.14-0.55, P = .002) obtained better results in death through subgroup analysis. Regarding safety outcomes, no difference was observed between 2 groups in terms of upper gastrointestinal bleeding (OR: 0.83, 95% CI, 0.27-2.52, P = .74), hyperglycemia (OR: 1.3, 95% CI, 0.68-2.49, P = .42), and super infection (OR: 1.11, 95% CI, 0.14-9.13, P = .92). CONCLUSION: Adjunctive corticosteroid yielded favorable outcomes in the treatment of severe community acquired pneumonia (SCAP) as evidenced by decreased all-cause mortality, incidence of septic shock, and requirement for mechanical ventilation without increasing risk of adverse events. Low dose (≤86 mg/d), prolonged use (>5 days) of corticosteroid in dosage modus of a maintenance dose after a bolus can be recommended as preferred regimen to guard against SCAP.

The Oncogene IARS2 Promotes Non-small Cell Lung Cancer Tumorigenesis by Activating the AKT/MTOR Pathway.

A limited number of studies have indicated an association between isoleucyl-tRNA synthetase 2 (IARS2) and tumorigenesis. We evaluated IARS2 protein expression in lung tumor tissues and paired non-tumor tissues. We found higher IARS2 expression in the tumor tissues, which was associated with the late Tumor and Node stages of the Tumor, Node, Metastasis staging system. Silencing IARS2 inhibited the activity of A549 and H1299 cells, resulting in G0/G1 stasis of A549 cells and mitochondrial apoptosis. IARS2 silencing was also found to inhibit NSCLC tumor growth in nude mice. Complementary DNA microarray analysis revealed 742 differentially expressed genes (507 upregulated and 235 downregulated) in IARS2-silenced A549 cells compared to controls. Ingenuity Pathway Analysis of the differential expression data suggested that multiple pathways are associated with IARS2 silencing in NSCLC cells; upstream analysis predicted the activation or inhibition of transcriptional regulators. Correlation analysis revealed that AKT and MTOR activities were significantly inhibited in IARS2-silenced cells, but were partially restored by the AKT-stimulating agent SC79. IARS2 appears to regulate lung cancer cell proliferation via the AKT/MTOR pathway. Our results help clarify the complex roles of IARS2 in tumorigenesis and suggest that it may be a novel regulator of lung cancer development.

RBM10 inhibits cell proliferation of lung adenocarcinoma via RAP1/AKT/CREB signalling pathway.

Initial functional studies have demonstrated that RNA-binding motif protein 10 (RBM10) can promote apoptosis and suppress cell proliferation; however, the results of several studies suggest a tumour-promoting role for RBM10. Herein, we assessed the involvement of RBM10 in lung adenocarcinoma cell proliferation and explored the potential molecular mechanism. We found that, both in vitro and in vivo, RBM10 overexpression suppresses lung adenocarcinoma cell proliferation, while its knockdown enhances cell proliferation. Using complementary DNA microarray analysis, we previously found that RBM10 overexpression induces significant down-regulation of RAP1A expression. In this study, we have confirmed that RBM10 decreases the activation of RAP1 and found that EPAC stimulation and inhibition can abolish the effects of RBM10 knockdown and overexpression, respectively, and regulate cell growth. This effect of RBM10 on proliferation was independent of the MAPK/ERK and P38/MAPK signalling pathways. We found that RBM10 reduces the phosphorylation of CREB via the AKT signalling pathway, suggesting that RBM10 exhibits its effect on lung adenocarcinoma cell proliferation via the RAP1/AKT/CREB signalling pathway.

CircRNAs and lung cancer: Biomarkers and master regulators.

CircRNAs are a class of competitive, endogenous, non-coding RNAs with closed-loop structures. High-throughput sequencing indicates that circRNAs are ubiquitously expressed in many eukaryotes. Biological functions of circRNAs include interaction with proteins and regulation of gene transcription, translation, and miRNA sponge activity. These functions suggest that circRNAs may be useful as novel biomarkers for disease diagnosis and prognosis. Lung cancer is known worldwide as the most common malignant tumor. It is also the main cause of cancer-related death. In recent years, it has become increasingly evident that circRNAs are involved in the proliferation, migration, and invasion of lung cancer cells. Differentially expressed circRNAs may be used as non-invasive diagnostic and prognostic markers for lung cancer. Therefore, they are considered a research hotspot for lung cancer studies. This article is a systematic review of mechanisms underlying the action, diagnosis, clinical aspects, and drug resistance of circRNAs in lung cancer.

Expression of RNA-binding motif 10 is associated with advanced tumor stage and malignant behaviors of lung adenocarcinoma cancer cells.

This study assessed RNA-binding motif 10 expression in lung adenocarcinoma tissues and examined the role and mechanism of RNA-binding motif 10 in the regulation of lung adenocarcinoma malignancy. Lung adenocarcinoma and corresponding adjacent non-tumor lung tissues from 41 patients were subjected to reverse transcription-polymerase chain reaction and Western blot assessment to detect RNA-binding motif 10 expression. Recombinant lentivirus carrying RNA-binding motif 10 complementary DNA was used to infect lung adenocarcinoma cell lines, A549 and H1299 cells. Complementary DNA microarray was used to profile RNA-binding motif 10-regulated genes. Levels of RNA-binding motif 10 messenger RNA and protein were significantly lower in lung adenocarcinoma tissues than those in paired non-tumor tissues (p < 0.001). Reduced RNA-binding motif 10 expression was found to be associated with an advanced tumor stage. RNA-binding motif 10 overexpression inhibited viability and colony formation capacity of lung adenocarcinoma cell lines and induced cell-cycle arrest at G0/G1 phase in A549 cells and at S phase in H1299 cells. Complementary DNA microarray analysis identified 304 upregulated and 386 downregulated genes induced by RNA-binding motif 10 overexpression, which may be involved in cancer, focal adhesion, peroxisome proliferator-activated receptor-regulated gene pathway, cytokine-cytokine receptor interaction, mitogen-activated protein kinase signaling, complement and coagulation cascades, platelet amyloid precursor protein pathway, extracellular matrix-receptor interaction, and small cell lung cancer-related genes. Expression of FGF2, EGFR, WNT5A, NF-κB, and RAP1A was downregulated, whereas expression of AKT2, BIRC3, and JUN was upregulated. RNA-binding motif 10 messenger RNA and protein were reduced in lung adenocarcinoma tissues, and RNA-binding motif 10 overexpression inhibited lung adenocarcinoma cancer cell malignant behavior in vitro. Molecularly, RNA-binding motif 10 regulates many gene pathways involving in the tumor development or progression.

Hyaluronic acid-modified zirconium phosphate nanoparticles for potential lung cancer therapy.

Novel tumor-targeting zirconium phosphate (ZP) nanoparticles modified with hyaluronic acid (HA) were developed (HA-ZP), with the aim of combining the drug-loading property of ZP and the tumor-targeting ability of HA to construct a tumor-targeting paclitaxel (PTX) delivery system for potential lung cancer therapy. The experimental results indicated that PTX loading into the HA-ZP nanoparticles was as high as 20.36%±4.37%, which is favorable for cancer therapy. PTX-loaded HA-ZP nanoparticles increased the accumulation of PTX in A549 lung cancer cells via HA-mediated endocytosis and exhibited superior anticancer activity in vitro. In vivo anticancer efficacy assay revealed that HA-ZP nanoparticles possessed preferable anticancer abilities, which exhibited minimized toxic side effects of PTX and strong tumor-suppression potential in clinical application.

Overexpression of RBM5 induces autophagy in human lung adenocarcinoma cells.

BACKGROUND: Dysfunctions in autophagy and apoptosis are closely interacted and play an important role in cancer development. RNA binding motif 5 (RBM5) is a tumor suppressor gene, which inhibits tumor cells' growth and enhances chemosensitivity through inducing apoptosis in our previous studies. In this study, we investigated the relationship between RBM5 overexpression and autophagy in human lung adenocarcinoma cells. METHODS: Human lung adenocarcinoma cancer (A549) cells were cultured in vitro and were transiently transfected with a RBM5 expressing plasmid (GV287-RBM5) or plasmid with scrambled control sequence. RBM5 expression was determined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot. Intracellular LC-3 I/II, Beclin-1, lysosome associated membrane protein-1 (LAMP1), Bcl-2, and NF-κB/p65 protein levels were detected by Western blot. Chemical staining with monodansylcadaverine (MDC) and acridine orange (AO) was applied to detect acidic vesicular organelles (AVOs). The ultrastructure changes were observed under transmission electron microscope (TEM). Then, transplanted tumor models of A549 cells on BALB/c nude mice were established and treated with the recombinant plasmids carried by attenuated Salmonella to induce RBM5 overexpression in tumor tissues. RBM5, LC-3, LAMP1, and Beclin1 expression was determined by immunohistochemistry staining in plasmids-treated A549 xenografts. RESULTS: Our study demonstrated that overexpression of RBM5 caused an increase in the autophagy-related proteins including LC3-I, LC3-II, LC3-II/LC3-I ratio, Beclin1, and LAMP1 in A549 cells. A large number of autophagosomes with double-membrane structure and AVOs were detected in the cytoplasm of A549 cells transfected with GV287-RBM5 at 24 h. We observed that the protein level of NF-κB/P65 was increased and the protein level of Bcl-2 decreased by RBM5 overexpression. Furthermore, treatment with an autophagy inhibitor, 3-MA, enhanced RBM5-induced cell death and chemosensitivity in A549 cells. Furthermore, we successfully established the lung adenocarcinoma animal model using A549 cells. Overexpression of RBM5 enhanced the LC-3, LAMP1, and Beclin1 expression in the A549 xenografts. CONCLUSIONS: Our findings showed for the first time that RBM5 overexpression induced autophagy in human lung adenocarcinoma cells, which might be driven by upregulation of Beclin1, NF-κB/P65, and downregulation of Bcl-2. RBM5-enhanced autophagy acts in a cytoprotective way and inhibition of autophagy may improve the anti-tumor efficacy of RBM5 in lung cancer.