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Background: Nonsmall cell lung carcinoma (NSCLC) is a major cause of cancer-related death worldwide. The resistance of NSCLC to chemical drugs, such as cisplatin (CDDP), poses a heavy burden for NSCLC therapy. Herein, the effects of circular_0008928 (circ_0008928) on the CDDP sensitivity and biological behavior of CDDP-resistant NSCLC cells and underlying mechanism are revealed. Materials and Methods: The expression of circ_0008928 and microRNA-488 (miR-488) was detected by quantitative real-time polymerase chain reaction. The expression of hexokinase 2 ( HK2 ) protein and exosome-specific proteins was determined by Western blot. The half-maximal inhibitory concentration (IC 50 ) value of CDDP was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell proliferation and migratory and invasive abilities were illustrated by cell counting kit-8 and transwell assays. Cell glycolysis metabolism was illustrated by extracellular acidification rate assay, glucose kit and lactate kit assays and Western blot analysis. The binding sites between miR-488 and circ_0008928 or HK2 were predicted by starbase or microT-CDS online database, and identified by dual-luciferase reporter and RNA immunoprecipitation assays. Results: Circ_0008928 expression and HK2 protein expression were significantly upregulated, while miR-488 expression was obviously downregulated in NSCLC cells and CDDP-resistant NSCLC cells. Circ_0008928 expression was increased in serum exosomes of CDDP-resistant NSCLC patients compared with CDDP-sensitive NSCLC patients. In addition, circ_0008928 silencing improved CDDP sensitivity and attenuated CDDP-induced cell proliferation, migration, invasion, and glycolysis metabolism. Circ_0008928 was a sponge of miR-488, and miR-488 bound to HK2 in CDDP-resistant NSCLC cells. Furthermore, both miR-488 inhibitor and HK2 overexpression attenuated circ_0008928 absence-mediated impacts on CDDP sensitivity and tumor process in CDDP-resistant NSCLC. Conclusions: Circ_0008928 knockdown improved CDDP sensitivity and hindered cell proliferation, migration, invasion, and glycolysis metabolism by miR-488/ HK2 axis in CDDP-resistant NSCLC. This finding provides a new mechanism for studying CDDP-resistant therapy in NSCLC.

The upstream regulators of microRNAs were rarely reported. Hydroquinone (HQ) is the main metabolite of benzene, one of the important environmental factors contributing to leukemia and lymphoma. In HQ-induced malignant transformed TK6 (TK6-HT) cells, the expression of PARP-1 and miR-223 were upregulated. When in PARP-1 silencing TK6-HT cells, miR-223 was downregulated and the apoptotic cell number correspondingly increased. In TK6 cells treated with HQ for different terms, the expression of miR-223 and PARP-1 were dynamically observed and found to be decreased and increased, respectively. Trichostatin A could increase the expression of miR-223, then the expression of HDAC1-2 and nuclear factor kappa B were found to be increased, but that of mH2A was decreased. PARP-1 silencing inhibited the protein expression of H3Ac, mH2A, and H3K27ac. By co-immunoprecipitation experiment, PARP-1 and HDAC2 were found to form a regulatory complex. In conclusion, we demonstrated that the upregulation of PARP-1 mediated activation of acetylation to promote the transcription of miR-223 possibly via coregulating with HDAC2, an epigenetic regulation mechanism involved in cell malignant transformation resulting from long-term exposure to HQ, in which course, H3K27ac might be a specific marker for the activation of histone H3, which also gives hints for benzene exposure research., (© 2022 Wiley Periodicals LLC.)

In view of the important roles played by Kinetochore proteins in mitosis, we believed that they may contribute to the development and progression of human cancers, which has been reported recently elsewhere. Kinetochore-associated 1 (KNTC1) participates in the segregation of sister chromatids during mitosis, the effects of which on non-small-cell lung cancer (NSCLC) remain unclear. Here, we sought to identify the biological significance of KNTC1 in NSCLC. KNTC1 protein expression in NSCLC tissues was investigated by immunohistochemistry. Lentivirus delivered short hairpin RNA (shRNA) was utilized to establish KNTC1 silence NSCLC cell lines. The effects of KNTC1 depletion on NSCLC cell proliferation, migration, apoptosis, and tumor formation were analyzed by MTT assay, wound-healing assay, transwell assay, flow cytometry assay, and in nude mouse models in vivo. After KNTC1 reduction, NSCLC cell viability, proliferation, migration, and invasion were restrained. A xenograft tumor model was also provided to demonstrate the inhibited tumorigenesis in NSCLC. In addition, the downstream mechanism analysis indicated that KNTC1 depletion was positively associated with PSMB8. The findings of the present study suggested that KNTC1 may have a pivotal role in mediating NSCLC progression and may act as a novel therapeutic target for NSCLC., (© 2022. The Author(s).)

The role of microRNAs (miRNAs) in tumor diagnosis and patients' prognosis has recently gained extensive research attention. This study was designed to analyze miRNA in lung adenocarcinoma (LUAD) using bioinformatics analysis and to identify novel biomarkers to predict overall survival (OS) for LUAD patients. Differential miRNA expression analysis was performed on LUAD, and normal tissues were extracted from The Cancer Genome Atlas (TCGA). Univariate Cox risk regression and least absolute shrinkage and selection operator (LASSO) Cox analysis were used to screen prognostic miRNAs and develop a risk score model. The prognostic performance of the system was examined utilizing the Kaplan-Meier and receiver operating characteristic (ROC) curves. Independent prognostic factors of LUAD were determined by multivariate Cox regression analysis. Nomogram was constructed according to the independent prognostic factors to evaluate the patients' one-, three- and five-year OS. A 7-miRNA signature based on miR-584-5p, miR-31-3p, miR-490-3, miR-4661-5p, miR-30e-5p, miR-582-5p, and miR-148a-3p was established. To categorize patients into high- and low-risk groups, the risk score was computed. The OS of the low-risk group was significantly longer than the high-risk group, and the signature showed high sensitivity and specificity in anticipating the one-, three- and five-year OS. The system was an independent factor in predicting the OS of LUAD patients and performed better when combined with the N stage in nomogram. A 7-miRNA signature developed in this study could accurately predict LUAD survival.

Background: Non-small cell lung carcinoma (NSCLC) is a malignancy with the highest mortality rate. Currently, surgery combined with radiotherapy is the first choice in the clinical treatment of lung carcinoma (LC); however, long-term radiotherapy leads to radiation resistance in patients, resulting in treatment failure., Methods: In this study, a new microRNA-218-5p (miRNA-218-5p) was identified, and its function in LC was investigated., Results: Reverse transcription quantitative polymerase chain reaction (RT-qPCR) results revealed that miRNA-218-5p was downregulated in LC. Overexpression or inhibition of miRNA-218-5p in LC and targeted binding of protein kinase, DNA-activated, catalytic polypeptide (PRKDC) to miRNA-218-5p were confirmed by comprehensive bioinformatic analysis. Exosomes from A549 and H1299 cells were cocultured with miRNA-218-5p and then cotransfected into radiation-resistant A549R and H1299R cells; the proliferation of radiation-resistant LC cells was found to be effectively inhibited and apoptosis was induced. Overexpression of miRNA-218-5p and X-irradiation could enhance the radiosensitivity of LC cells. Exogenous miRNA-218-5p derived from A549 and H1299 cells could be transfected into radiation-resistant LC cells and could inhibit PRKDC expression, thus accelerating DNA damage, apoptosis, and radiation sensitization of LC cells., Conclusions: miRNA-218-5p could induce apoptosis and enhance the radiosensitivity of LC cells through regulatory activities, thus suggesting its application as a potential target for LC treatment., (© 2021 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Long non‑coding RNAs (lncRNAs) have been discovered to participate in the progression of various types of disease and may be a promising biomarker for atherosclerosis (AS). The present study aimed to investigate the regulatory mechanisms of the lncRNA, small nucleolar RNA host gene 7‑003 (SNHG7‑003), on the proliferation, migration and invasion of vascular smooth muscle cells (VSMCs). VSMCs were first stimulated with oxidized low‑density lipoprotein (ox‑LDL) to simulate AS in a high fat environment. The expression levels of SNHG7‑003, microRNA (miRNA/miR)‑1306‑5p and sirtuin 7 (SIRT7) were analyzed by reverse transcription‑quantitative PCR and the effects of each of these factors on VSMC proliferation, migration and invasion were determined by Cell Counting Kit‑8, wound healing and Transwell assays, respectively. Western blot analysis was also used to analyze the protein expression levels of α‑smooth muscle actin (α‑SMA), matrix metalloproteinase (MMP)2 and MMP9. The interactions between SNHG7‑003 or SIRT7 and miR‑1306‑5p were determined using dual‑luciferase reporter assays. The results revealed that the SNHG7‑003 expression levels were downregulated in VSMCs exposed to ox‑LDL, while the overexpression (OE) of SNHG7‑003 significantly inhibited the proliferation, migration and invasion of VSMCs induced by ox‑LDL. Transfection with miR‑1306‑5p mimic abrogated the effects of the inhibitory effects induced by SNHG7‑003 OE. SIRT7 was validated to be a target gene of miR‑1306‑5p, exhibiting similar inhibitory effects as SNHG7‑003 in AS. It was also discovered to be involved in the regulatory effects of the SNHG7‑003/miR‑1306‑5p axis in VSMCs. On the whole, the findings of the present study indicate that SNHG7‑003 may inhibit the proliferation, migration and invasion of VSMCs via the miR‑1306‑5p/SIRT7 signaling pathway. These findings may provide a novel basis for the development of treatment strategies for AS.

Embryo implantation plays a decisive role in pregnancy. While in the process of implantation, microRNA (miRNA) is an important regulatory factor in the post transcriptional level. However, the role of many miRNAs in embryo implantation remained unknown. In this study, microRNA-183 (miR-183) was found differentially expressed in mouse uterus during implantation. In vivo treatment of miR-183 agomir in the uterine horn before implantation could eliminate the number of implantation site. The localization of miR-183 in mouse uteri gradually changed from epithelial to stromal layer in early pregnancy. Mice implantation models demonstrated that the decrease of miR-183 was mainly caused by maternal factors. Loss and gain function of miR-183 in endometrial cell lines showed that miR-183 could inhibit cell migration, invasion and apoptosis. MiR-183 could inhibit embryo implantation by binding Heparin-Binding EGF-like growth factor (Hbegf) and Laminin gamma one (Lamc1), which were key genes in embryo apposition and penetration. All these evidences indicate that miR-183 plays an important role during embryo implantation. This study provides new insights into the functions of miR-183 during embryo implantation and the development of contraceptive drugs in early pregnancy., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The establishment of uterine receptivity is a prerequisite for embryo implantation and begins with the transformation of the luminal epithelium. MicroRNAs (miRNAs) have been widely reported to be involved in the regulation of embryo implantation, but their roles in establishing uterine receptivity remain unclear. In this study, through small RNA sequencing analysis, we showed that a low level of miR-192-5p is essential for initiating implantation in mice, and transient upregulation of miR-192-5p led to implantation failure. In situ hybridization results revealed that miR-192-5p was primarily expressed in the endometrial epithelium, and dysregulation of miR-192-5p interfered with the performance of the luminal epithelium, resulting in inadequate receptivity. By manipulating miR-192-5p expression in mouse uterus and an endometrial epithelial cell line, we showed that miR-192-5p maintains cell polarity through stabilizing adherens junction protein E-cadherin, thereby preventing epithelial-mesenchymal transition. Furthermore, miR-192-5p preserved the pattern of microvilli as well as Muc1 expression on the apical membrane of epithelial cells, thereby avoiding embryo adhesion. Moreover, miR-192-5p was found to be regulated by ovarian steroids. Collectively, this study demonstrated that the physiological role of miR-192-5p in mouse uterus is to maintain the nonreceptive state of epithelial cells and prevent their transformation to the receptive state. Thus, a sustained high level of miR-192-5p is detrimental to embryo implantation. These findings help elucidate the mechanisms involved in miRNA-based regulation of uterine physiology in early pregnancy, and may even contribute to the diagnosis and treatment of infertility., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Benzene exposure is a risk factor of acute myeloid leukemia (AML), during such carcinogenesis long non-coding RNAs (lncRNAs) are important epigenetic regulators. HOTAIRM1 (HOXA transcript antisense RNA, myeloid-specific 1) plays an indispensable role in the development of AML. Hydroquinone (HQ) is one major metabolite of benzene and its ideal replacement in toxicology research. But the influence of benzene or HQ on HOTAIRM1 expression in AML associated pathway is still unclear. In the TK6 cells with short-term exposure to HQ (HQ-ST cells) or long term HQ exposure induced malignant transformed TK6 cells (HQ-MT cells), the relationship between DNMT3b and HOTAIRM1 was explored. Comparing to counterparts, HOTAIRM1 expression was increased firstly and then decreased in HQ-ST cells, and definitely decreased in HQ-MT cells; while the expression change tendency of DNMT3b was in contrast to that of HOTAIRM1. Moreover, the average HOTAIRM1 expression of 17 paired workers being exposed to benzene within 1.5 years was increased, but that of the remaining 92 paired workers with longer exposure time was decreased. Furthermore, in 5-AzaC (DNA methyltransferase inhibitor) or TSA (histone deacetylation inhibitor) treated HQ-MT cells, the expression of HOTAIRM1 was restored by reduced DNA promoter methylation levels. HQ-MT cells with DNMT3b knockout by CRISPR/Cas9 displayed the promoter hypomethylation and the increase of HOTAIRM1, also confirmed in benzene exposure workers. These suggest that long term exposure to HQ or benzene might induce the increase of DNMT3b expression and the promoter hypermethylation to silence the expression of HOTAIRM1, a possible tumor-suppressor in the AML associated carcinogenesis pathway., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interest or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Synchronous communication between the developing embryo and the receptive endometrium is crucial for embryo implantation. Thus, uterine receptivity evaluation is vital in managing recurrent implantation failure (RIF). The potential roles of small extracellular vesicle (sEV) miRNAs in pregnancy have been widely studied. However, the systematic study of sEVs derived from endometrium and its cargos during the implantation stage have not yet been reported. In this study, we isolated endometrium-derived sEVs from the mouse endometrium on D2 (pre-receptive phase), D4 (receptive phase), and D5 (implantation) of pregnancy. Herein, we reveal that multivesicular bodies (MVBs) in the endometrium increase in number during the window of implantation (WOI). Moreover, our findings indicate that CD63, a well-known sEV marker, is expressed in the luminal and glandular epithelium of mouse endometrium. The sEV miRNA expression profiles indicated that miR-34c-5p, miR-210, miR-369-5p, miR-30b, and miR-582-5p are enriched during WOI. Further, we integrated the RIF's database analysis results and found out that miR-34c-5p regulates growth arrest specific 1 (GAS1) for normal embryo implantation. Notably, miR-34c-5p is downregulated during implantation but upregulated in sEVs. An implication of this is the possibility that sEVs miR-34c-5p could be used to evaluate uterine states. In conclusion, these findings suggest that the endometrium derived-sEV miRNAs are potential biomarkers in determining the appropriate period for embryo implantation. This study also has several important implications for future practice, including therapy of infertility.

Hydroquinone (HQ), one of the major metabolites of benzene, can induce aberrant gene expression. MiR-155, a tumor activator, participates in various biological processes, including DNA damage response. However, the molecular mechanism of aberrant miR-155 expression is still not completely elucidated. Here, we investigated the mechanism of abnormal expression of miR-155 induced by poly(ADP-ribose)polymerase-1 (PARP-1) expression in HQ-treated TK6 lymphoblastoid cells. We examined the expression of genes related to abnormal expression of miR-155 to explore the reason for this phenomenon. The results of the present study showed that miR-155 was significantly increased and reactive oxygen species (ROS) were decreased in cells treated with HQ for 72 h compared with PBS-treated cells. Meanwhile, E4F1, PARP-1 and PARP-1 related co-regulators (NF-κB, HDAC1, and HDAC2), acetylated histone H3 (H3Ac) were increased in a concentration-dependent manner. Experiments for treatment with 5-AzaC (DNMTs inhibitor), TSA (HDACs inhibitor), DOX (to activate PARP-1) or MG132 (proteasome inhibitor) revealed that the MBDs and PARP-1 was positively associated with miR-155 expression. Moreover, in cells treated with HQ in conjunction with PARP-1 knockdown, expression of miR-155, H3Ac and MBD2 protein were decreased, compared with negative control. In conclusion, PARP-1 activates expression of miR-155 via acetylation by regulating MBD2 in TK6 cells exposed to HQ., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Growing evidence indicates that miR-200c is involved in carcinogenesis and tumor progression in non-small-cell lung cancer (NSCLC). However, its precise biological role remains largely elusive., Methods: The functions of miR-200c and USP25 in migration/invasion and lung metastasis formation were determined by transwell and tail vein injection assays, respectively. The potential regulatory targets of miR-200c were determined by prediction tools, correlation with target protein expression, and luciferase reporter assay. The mRNA expression levels of miR-200c and USP25 were examined in NSCLC cell lines and patient specimens using quantitative reverse transcription-PCR. The protein expression levels of USP25 were examined in NSCLC cell lines and patient specimens using western blot and immunohistochemical staining., Results: We demonstrated that over-expression of miR-200c inhibited NSCLC cells migration, invasion, epithelial-mesenchymal transition (EMT) in vitro and lung metastasis formation in vivo. Further studies revealed that USP25 was a downstream target of miR-200c in NSCLC cells as miR-200c bound directly to the 3'-untranslated region of USP25, thus reducing both the messenger RNA and protein levels of USP25. Silencing of the USP25 gene recapitulated the effects of miR-200c over-expression. Clinical analysis indicated that miR-200c was negatively correlated with clinical stage, lymph node metastasis in NSCLC patients. Moreover, USP25 protein and mRNA level expressions were higher in NSCLC patients, compared to healthy control, and correlated with clinical stage and lymphatic node metastasis., Conclusions: These findings indicate that miR-200c exerts tumor-suppressive effects for NSCLC through the suppression of USP25 expression and suggests a new therapeutic application of miR-200c in the treatment of NSCLC.

The roles of miRNAs in the onset of hearing and deafness are beginning to be revealed. Although there has been no reported link between chloride intracellular channel 5 (CLIC5) and the miR-183 family to date, we here present evidence that they are co-expressed in the inner ear and have functions that are related to stereocilia. Moreover, CLIC5 contains a single predicted and highly conserved miR-96/-182 binding site within its 3'-UTR. Our current results further show that miR-96/-182 and CLIC5 are co-expressed in HEI-OC1 cells, in which two isoforms of the CLIC5 protein exist. Furthermore, miR-96 and miR-182 were found to be specifically overexpressed in HEI-OC1 cells into which mimics of these molecules had been transfected by liposomes causing the downregulation of CLIC5 at both the mRNA and protein levels. Finally, miR-96/-182 specifically downregulate the expression of the luciferase reporter gene which was cloned into a mouse CLIC5 3'-UTR fragment containing the wild-type miR-96/-182 target sequence. Our findings thus suggest that CLIC5 is directly regulated by miR-96 and miR-182 and that the target sequence in this regard is located between nucleotides 760-766 within the CLIC5 3'-UTR., (Copyright © 2012 Elsevier Ltd. All rights reserved.)