Downregulation of microRNA‐92b‐3p suppresses proliferation, migration, and invasion of gastric cancer SGC‐7901 cells by targeting Homeobox D10

New perspectives of exosomes in urologic malignancies - Mainly focus on biomarkers and tumor microenvironment

Bladder cancer (BCa) and renal cell carcinoma (RCC) are prevalent urologic malignancies (UM) characterized by high morbidity and frequent recurrence. Current diagnostic approaches, often invasive, often indicate an advanced disease stage. And the complex tumor microenvironment often promotes tumor progression and induces resistance to chemotherapy. Current diagnostic and therapeutic modalities often fail to achieve satisfactory outcomes for patients. Exosomes transport diverse cargoes, including cytokines, proteins, lipids, non-coding RNAs, and microRNAs, crucial for intercellular communication. Exosomes have shown potential as biomarkers for UM, participating in tumor progression, especially within the tumor microenvironment (TME), including tumor cell apoptosis, proliferation, migration, invasion, depletion of immune cell function, epithelial-mesenchymal transition (EMT), angiogenesis, and more.In this review, we summarize research advances related to exosomes in UM, focusing on the role of exosomes as biomarkers in bladder and renal cancer, highlighting their significance within the TME.

Extracellular vesicles derived from melanoma cells induce carcinoma-associated fibroblasts via miR-92b-3p mediated downregulation of PTEN

In melanoma, carcinoma-associated fibroblasts (CAFs) are important cellular components in the tumour microenvironment due to their potential to promote tumour growth and metastatic spread of malignant cells. Melanoma cells have the ability to affect non-tumour cells in the microenvironment by releasing extracellular vesicles (EVs). The mechanisms responsible for reprogramming normal dermal fibroblasts (NHDFs) into CAFs remain incompletely understood. However, it is likely thought to be mediated by melanoma-specific miRNAs, which are transported by EVs derived from melanoma cells. Therefore, we wondered if one of the most enriched miRNAs in EVs secreted by melanoma cells, miR-92b-3p, is involved in the conversion of normal fibroblasts into CAFs. We observed that melanoma cell-derived EVs indeed delivered miR-92b-3p into NHDFs and that its accumulation correlated with CAF formation, as demonstrated by enhanced expression of CAF marker genes and increased proliferation and migration. Overexpression of miR-92b-3p in NHDFs revealed similar results, while EVs deficient of miR-92b-3p did not induce a CAF phenotype. As a target we identified PTEN, whose repression led to increased expression of CAF markers. We thus provide a novel pathway of intercellular communication by which melanoma cells control the transformation of CAFs by virtue of EV-transported miRNAs.

microRNA-92b-3p augments colon cancer development through inhibiting KLF3

Colon cancer (CC) is a tumor of the large intestine. miR-92b-3p is often deregulated in the tumorigensis. Here, the role of miR-92b-3p in the development of CC was investigated. miR-92b-3p and Kruppel-like factor 3 (KLF3) expression was examined in CC tissues and cells. miR-92b-3p inhibitor or KLF3 overexpression vector was transfected into CC cells, respectively to observe its role in CC cell proliferation, invasion, migration, and apoptosis. The targeting relationship between miR-92b-3p and KLF3 was validated. Meanwhile, rescue experiments were performed by co-transfection of miR-92b-3p inhibitor and KLF3 siRNA, followed by determining CC cell proliferation, invasion, migration, and apoptosis. Higher miR-92b-3p and lower KLF3 expression levels were observed in CC tissues and cells. miR-92b-3p inhibition or KLF3 overexpression reduced proliferation, invasion, and migration whereas induced apoptosis of CC cells. KLF3 was validated to be the target gene of miR-92b-3p. Depletion of KLF3 could reverse the antitumor role of miR-92b-3p inhibition in CC cells. miR-92b-3p augments CC development through inhibiting KLF3, which may confers a novel way to develop future treatment target.

MircroRNA-92b as a negative regulator of the TGF-β signaling by targeting the type I receptor

Transforming growth factor β1 (TGFβ1) has been identified as a major pathogenic factor underlying the development of chronic kidney disease (CKD). This study investigated the role of miR-92b-3p in the progression of renal fibrosis in unilateral ureteral occlusion (UUO) and unilateral ischemia-reperfusion injury (uIRI) mouse models, as well as explored its underlying mechanisms in human proximal tubular epithelial (HK2) cells. We found that renal fibrosis increased in UUO mice after miR-92b knockout, while it reduced in miR-92b overexpressing mice. MiR-92b knockout aggravated renal fibrosis in uIRI mice. RNA-sequencing analysis, the luciferase reporter assay, qPCR analysis, and western blotting confirmed that miR-92b-3p directly targeted TGF-β receptor 1, thereby ameliorating renal fibrosis by suppressing the TGF-β signaling pathway. Furthermore, we found that TGF-β suppressed miR-92b transcription through Snail family transcriptional repressors 1 and 2. Our results suggest that miR-92b-3p may serve as a novel therapeutic for mitigating fibrosis in CKD.

Functional mechanism of miR-92b-3p in osteogenic differentiation of fibroblasts in patients with ankylosing spondylitis via the TOB1/BMP/Smad pathway

BACKGROUND

Ankylosing spondylitis (AS) is a chronic inflammatory arthritis. Upregulation of microRNA (miR)-92b-3p is associated with enhanced osteoblastic differentiation. The current study sought to investigate the functional mechanism of miR-92b-3p in osteogenic differentiation of AS fibroblasts.

METHODS

First, fibroblasts were isolated from AS and non-AS patients and cultured. Next, cell morphology was observed, cell proliferation was assessed and the vimentin expression pattern was determined. Alkaline phosphatase (ALP) activity and levels of osteogenic markers RUNX2, OPN, OSX, and COL I were additionally measured, followed by determination of miR-92b-3p and TOB1 levels. The binding site of miR-92b-3p and TOB1 was predicted, and their target relationship was validated. Lastly, miR-92b-3p inhibitor, si-TOB1, and the BMP/Smad signaling pathway inhibitor LDN193189 were delivered into AS fibroblasts to evaluate the osteogenic differentiation of AS fibroblasts and the activation of the BMP/Smad pathway.

RESULTS

miR-92b-3p was highly expressed in AS fibroblasts. AS fibroblasts showed enhanced osteogenic differentiation and proliferation, while inhibition of miR-92b-3p suppressed osteogenic differentiation and proliferation of AS fibroblasts. miR-92b-3p targeted TOB1, and TOB1 was poorly expressed in AS fibroblasts. The concurrent downregulation of TOB1 and inhibition of miR-92b-3p elevated the levels of RUNX2, OPN, OSX, and COL I and ALP activity and further enhanced the proliferation of AS fibroblasts. The BMP/Smad pathway was activated in AS fibroblasts. Silencing miR-92b-3p could inhibit the activation of the BMP/Smad pathway by upregulating TOB1. Inhibition of the BMP/Smad pathway reduced the number of calcified nodules and hindered the osteogenic differentiation and proliferation of AS fibroblasts.

CONCLUSION

Our findings highlighted that silencing miR-92b-3p inhibited the osteogenic differentiation and proliferation of AS fibroblasts by upregulation of TOB1 and inhibition of the BMP/Smad pathway.

A circulating microRNA panel as a novel dynamic monitor for oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) has high recurrence and mortality rates despite advances in diagnosis and treatment. Therefore, it is necessary to identify new biomarkers for early detection, efficient monitoring, and prognosis prediction. Since microRNA (miRNA) is stable and detectable in serum, it has been reported to inform the diagnosis and monitor disease progression through liquid biopsy. In this study, a circulating specific miRNA panel in OSCC patients was developed, and its usefulness as a dynamic monitor was validated. Small RNAs were extracted from the serum of OSCC patients (n = 4) and normal controls (n = 6) and profiled using next-generation sequencing. NGS identified 42 differentially expressed miRNAs (DEmiRNAs) in serum between patients with OSCC and healthy controls, with threefold differences (p < 0.05). Combining the 42 DEmiRNAs and The Cancer Genome Atlas (TCGA) databases OSCC cohort, 9 overlapping DEmiRNAs were screened out. Finally, 4 significantly up-regulated miRNAs (miR-92a-3p, miR-92b-3p, miR-320c and miR-629-5p) were identified from OSCC patients via validation in the Chungnam National University Hospital cohort. Application of the specific miRNA panel for distinguishing OSCC patients from healthy controls produced specificity and sensitivity of 97.8 and 74%, respectively. In addition, the serum levels of these 4 miRNAs significantly decreased after complete surgical resection and increased after recurrence. We suggest that circulating 4-miRNA panel might be promising non-invasive predictors for diagnosing and monitoring the progression of patients with OSCC.

Prognostic value of microRNAs in patients with small cell lung cancer: a meta-analysis

BACKGROUND

An increasing number of studies have shown that microRNAs play an important role in the occurrence and development of small cell lung cancer, which mainly manifest as oncogenic and tumor inhibition. Therefore, microRNAs may affect the survival of patients with small cell lung cancer. In this meta-analysis, we will evaluate the role of microRNAs in the overall survival of patients with small cell lung cancer, which may provide valuable information for the treatment of small cell lung cancer.

METHODS

We searched the PubMed, Embase, and Web of Science online databases to determine the effect of microRNAs on the prognosis of patients with small cell lung cancer. The data and characteristics of each study were extracted, and the hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to estimate the effect.

RESULTS

A total of 7 articles, involving 427 subjects and 15 studies, were included in this meta-analysis. The pooled HR of the relationship between the microRNA expression level and the overall survival rate of small cell lung cancer patients was 1.25 (95% CI: 1.06-1.47). There was a significant difference in the prognostic value of oncogenic and tumor inhibition microRNAs among patients with small cell lung cancer, with pooled HRs of 1.60 (95% CI: 1.35-1.90) and 0.42 (95% CI: 0.30-0.57), respectively.

CONCLUSIONS

MicroRNAs have a significant impact on the overall survival of small cell lung cancer patients, suggesting that microRNAs can be used as potential prognostic markers and may provide treatment strategies for small cell lung cancer patients.

TRIAL REGISTRATION

The protocol was registered on PROSPERO website with the registration number of CRD42022334363. The relevant registration information can be obtained from the website https://www.crd.york.ac.uk/prospero/#searchadvanced .

Significance of HOXD transcription factors family in progression, migration and angiogenesis of cancer

The transcription factors (TFs) of the HOX family play significant roles during early embryonic development and cellular processes. They also play a key role in tumorigenesis as tumor oncogenes or suppressors. Furthermore, TFs of the HOXD geFIne cluster affect proliferation, migration, and invasion of tumors. Consequently, dysregulated activity of HOXD TFs has been linked to clinicopathological characteristics of cancer. HOXD TFs are regulated by non-coding RNAs and methylation of DNA on promoter and enhancer regions. In addition, HOXD genes modulate the biological function of cancer cells via the MEK and AKT signaling pathways, thus, making HOXD TFs, a suitable molecular marker for cancer prognosis and therapy. In this review, we summarized the roles of HOXD TFs in different cancers and highlighted its potential as a diagnostic and therapeutic target.

Inhibition of Homeobox D10 Alleviates Acute Kidney Injury by Upregulating PI3K/AKT Signaling Proteins

Purpose. To observe the protective effect of homeobox D10 (HOXD10) on acute kidney injury (AKI) by regulating PI3K/AKT signaling pathway is the purpose of this study.Methods. 30 rats were randomly divided into three groups: blank control group, model group, and HOXD10 interference group. The kidney function indexes, HOXD10 protein expression, histopathological features, tubulointerstitial injury, and PI3K and AKT protein expression levels of the three groups were analyzed. Results. Compared with the blank control group, the kidney weight, BUN and SCr in model group increased significantly, and TIL score was higher ( $P>0.05$ ). The expression of HOXD10 in model group and HOXD10 interference group were higher than blank control group, and the expression of HOXD10 in HOXD10 interference group was lower than model group ( $P<0.05$ ). After we administered HOXD10 blocker to AKI rats, pathological sections by HE staining showed that the kidney tissue damage was significantly reduced compared with the model group, and the expression levels of BUN and SCr in kidney tissue decreased, and the TIL score decreased. The expression of p-PI3K and p-AKT decreased after kidney injury. Compared with the model group, the phosphorylation levels of PI3K and AKT in HOXD10 interference group were significantly increased ( $P<0.05$ ). Conclusion. Downregulation of HOXD10 can play a protective role on AKI by activating PI3K/AKT signaling pathway, which can reduce tubulointerstitial injury and improve kidney function.

Upregulation of homeobox D10 expression suppresses invasion and migration of clear cell renal cell carcinoma through targeting of E-cadherin

Background

Clear cell renal cell carcinoma (CCRCC) is one of the most common types of renal cell carcinoma. Accumulating evidence indicates that homeobox D10 (HOXD10) acts as a tumor suppressor or oncogene in various carcinomas. However, the regulation and potential mechanisms of HOXD10 in CCRCC remain largely unknown.

Purpose

To explore the effect and potential mechanism of HOXD10 on the invasion and migration of CCRCC cells.

Methods

The expression of HOXD10, E-cadherin and other epithelial mesenchymal transition (EMT)-related proteins was assessed by reverse transcription-quantitative real-time PCR (qRT-PCR) and Western blots. A series of functional assays were performed in RCC cell lines to explore the function of HOXD10 in CCRCC progression. Bioinformatics analysis, ChIP assays, and dual luciferase reporter assays were utilized to identify the interaction between HOXD10 and E-cadherin.

Results

Low expression of HOXD10 and E-cadherin was observed in CCRCC tissues and ACHN and 786-O cells. Downregulation of HOXD10 expression was correlated with the TNM stage of CCRCC patients. Functional experiments demonstrated that malignant biological ability was significantly inhibited by HOXD10 overexpression in RCC cells. Moreover, E-cadherin was a potential target gene of HOXD10, as evidenced by a series of assays. In addition, overexpression of HOXD10 inhibited the progression of CCRCC by regulating the expression of E-cadherin, vimentin, and β-catenin in vitro.

Conclusion

HOXD10 acts as a tumor suppressor and suppresses invasion and migration of CCRCC cells by regulating E-cadherin and EMT processes. Thus, targeting HOXD10 may be a therapeutic strategy for CCRCC treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11033-021-06993-8.

MiR-92b-3p Inhibits Proliferation of HER2-Positive Breast Cancer Cell by Targeting circCDYL

Objectives

Circular RNA (circRNA) is a novel class of RNA, which exhibits powerful biological function in regulating cellular fate of various tumors. Previously, we had demonstrated that over-expression of circRNA circCDYL promoted progression of HER2-negative (HER2^–) breast cancer via miR-1275-ULK1/ATG7-autophagic axis. However, the role of circCDYL in HER2-positive (HER2⁺) breast cancer, in particular its role in modulating cell proliferation, one of the most important characteristics of cellular fate, is unclear.

Materials and methods

qRT-PCR and in situ hybridization analyses were performed to examine the expression of circCDYL and miR-92b-3p in breast cancer tissues or cell lines. The biological function of circCDYL and miR-92b-3p were assessed by plate colony formation and cell viability assays and orthotopic animal models. In mechanistic study, circRNAs pull-down, RNA immunoprecipitation, dual luciferase report, western blot, immunohistochemical and immunofluorescence staining assays were performed.

Results

CircCDYL was high-expressed in HER2⁺ breast cancer tissue, similar with that in HER2^– breast cancer tissue. Silencing HER2 gene had no effect on expression of circCDYL in HER2⁺ breast cancer cells. Over-expression of circCDYL promoted proliferation of HER2⁺ breast cancer cells but not through miR-1275-ULK1/ATG7-autophagic axis. CircRNA pull down and miRNA deep-sequencing demonstrated the binding of miR-92b-3p and circCDYL. Interestingly, circCDYL did not act as miR-92b-3p sponge, but was degraded in miR-92b-3p-dependent silencing manner. Clinically, expression of circCDYL and miR-92b-3p was associated with clinical outcome of HER2⁺ breast cancer patients.

Conclusion

MiR-92b-3p-dependent cleavage of circCDYL was an essential mechanism in regulating cell proliferation of HER2⁺ breast cancer cells. CircCDYL was proved to be a potential therapeutic target for HER2⁺ breast cancer, and both circCDYL and miR-92b-3p might be potential biomarkers in predicting clinical outcome of HER2⁺ breast cancer patients.

lncRNA MALAT1/miR‑26a/26b/ST8SIA4 axis mediates cell invasion and migration in breast cancer cell lines

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a long non-coding RNA that is overexpressed in various human cancers, including breast cancer. Evidence has associated the function of the α-2,8-sialyltransferase (ST8SIA) family with breast cancer. The present study aimed to investigate the potential roles of MALAT1 in breast cancer development and progression using analyses of both breast cancer tissues and cell lines. The mRNA levels of MALAT1, microRNA (miR)-26a/26b and ST8SIA4 were detected by reverse transcription-quantitative PCR (RT-qPCR) and the protein level of ST8SIA4 was assessed by western blot analysis. Cell proliferation, invasion and migration were detected by CCK-8, wound healing and Transwell assays, respectively. Interactions between MALAT1 and miR-26a/26b were assessed using fluorescence in situ hybridization, RNA immunoprecipitation and luciferase reporter assays. Herein, different levels of MALAT1 were primarily observed in human breast cancer samples and cells. Upregulated MALAT1 was a crucial predictor of poor breast cancer prognosis. Altered MALAT1 modulated cell progression in breast cancer. Moreover, miR-26a/26b was confirmed as a direct regulator of MALAT1, and ST8SIA4 was predicted as a target of miR-26a/26b. Functional analysis in human breast cancer cell lines demonstrated that MALAT1 modulated breast cancer cell tumorigenicity by acting as a competing endogenous lncRNA (ceRNA) to regulate ST8SIA4 levels by sponging miR-26a/26b. The identification of the MALAT1/miR-26a/26b/ST8SIA4 axis which contributes to breast cancer progression may constitute a potential new therapeutic target.

MicroRNA-92b augments sorafenib resistance in hepatocellular carcinoma via targeting PTEN to activate PI3K/AKT/mTOR signaling

Sorafenib (SOR) resistance is still a significant challenge for the effective treatment of hepatocellular carcinoma (HCC). The mechanism of sorafenib resistance remains unclear. Several microRNAs (miRNAs) have been identified as playing a role in impairing the sensitivity of tumor cells to treatment. We examined the mechanism behind the role of miR-92b in mediating sorafenib resistance in HCC cells. We detected that miR-92b expression was significantly upregulated in SOR-resistant HepG2/SOR cells compared to parental HepG2/WT cells. After transfection with miR-92b inhibitor, the proliferation of HepG2/SOR cells was remarkably weakened and rates of apoptosis significantly increased. PTEN was considered to be a functional target of miR-92b according to a luciferase reporter assay. Knockdown of PTEN significantly impaired the ability of miR-92b inhibitor on increasing sorafenib sensitivity of HepG2/SOR cells. Furthermore, we confirmed by western blotting and immunofluorescence that miR-92b can mediate sorafenib resistance by activating the PI3K/AKT/mTOR pathway in HCC cells by directly targeting PTEN. These findings further validate the mechanism of miR-92b in SOR resistance in HCC treatment.

Exosomal miR-92b-3p Promotes Chemoresistance of Small Cell Lung Cancer Through the PTEN/AKT Pathway

Resistance to first-line chemotherapy drugs has become an obstacle to improving the clinical prognosis of patients with small cell lung cancer (SCLC). Exosomal microRNAs have been shown to play pro- and anti-chemoresistant roles in various cancers, but their role in SCLC chemoresistance has never been explored. In this study, we observed that the expression of exosomal miR-92b-3p was significantly increased in patients who developed chemoresistance. Luciferase reporter analysis confirmed that PTEN was a target gene of miR-92b-3p. The PTEN/AKT regulatory network was related to miR-92b-3p-mediated cell migration and chemoresistance in vitro and in vivo in SCLC. Importantly, exosomes isolated from the conditioned medium of SBC-3 cells overexpressing miR-92b-3p could promote SCLC chemoresistance and cell migration. Furthermore, we found that plasma miR-92b-3p levels were significantly higher in patients with chemoresistant SCLC than in those with chemosensitive SCLC, but the levels were down-regulated in patients who achieved remission. Kaplan–Meier analysis showed that SCLC patients with high miR-92b-3p expression were associated with shorter progression-free survival. Overall, our results suggested that exosomal miR-92b-3p is a potential dynamic biomarker to monitor chemoresistance in SCLC and represents a promising therapeutic target for chemoresistant SCLC.

Optical tweezers study of membrane fluidity in small cell lung cancer cells

The fluidity of the cell membrane is closely related to cancer metastasis/invasion. To test the relationship of membrane fluidity and invasiveness, we first demonstrated that transfection of small RNA miR-92b-3p can significantly increase invasiveness of the small cell lung cancer cell line SHP77. Then optical tweezers were used to measure membrane fluidity. This study employed continuous and step-like stretching methods to examine fluidity changes in SHP77 cell membranes before and after miR-92b-3p transfection. A newly developed physical model was used to derive the effective viscosity and static tension of the cell membrane from relaxation curves obtained via step-like stretching. Experiments showed that invasiveness and fluidity increased significantly after miR-92b-3p transfection. This study paved the way toward a better understanding of cancer cell invasion and membrane mechanical characteristics.

Enforced expression of miR-92b blunts E. coli lipopolysaccharide-mediated inflammatory injury by activating the PI3K/AKT/β-catenin pathway via targeting PTEN

Endometritis is a reproductive disorder characterized by an inflammatory response in the endometrium, which causes significant economic losses to the dairy farming industry. MicroRNAs (miRNAs) are implicated in the inflammatory response and immune regulation following infection by pathogenic bacteria. Recent miRNA microarray analysis showed an altered expression of miR-92b in cows with endometritis. In the present study, we set out to investigate the regulatory mechanism of miR-92b in endometritis. Here, qPCR results first validated that miR-92b was down-regulated during endometritis. And then, bovine endometrial epithelial cells (BEND cells) stimulated by high concentration of lipopolysaccharide (LPS) were employed as an in vitro inflammatory injury model. Our data showed that overexpression of miR-92b significantly suppressed the activation of Toll-like receptor 4 (TLR4) and nuclear factor-κB (NF‐κB) in LPS-stimulated BEND cells, thereby reducing pro-inflammatory cytokines release and inhibiting cell apoptosis. Looking into the molecular mechanisms of regulation of inflammatory injury by miR-92b, we observed that overexpression of miR-92b restrained TLR4/NF‐κB by activating the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT)/β-catenin pathway. Furthermore, the luciferase reporter assay suggested that miR-92b targeted inhibition of phosphatase and tensin homolog (PTEN), an inhibitor of the PI3K/AKT/β-catenin pathway. Importantly, in vivo experiments confirmed that up-regulation of miR-92b attenuated the pathological injury in an experimental murine model of LPS-induced endometritis. Collectively, these findings show that enforced expression of miR-92b alleviates LPS-induced inflammatory injury by activating the PI3K/AKT/β-catenin pathway via targeting PTEN, suggesting a potential application for miR-92b-based therapy to treat endometritis or other inflammatory diseases.

microRNAs Mediated Regulation of the Ribosomal Proteins and its Consequences on the Global Translation of Proteins

Ribosomal proteins (RPs) are mostly derived from the energy-consuming enzyme families such as ATP-dependent RNA helicases, AAA-ATPases, GTPases and kinases, and are important structural components of the ribosome, which is a supramolecular ribonucleoprotein complex, composed of Ribosomal RNA (rRNA) and RPs, coordinates the translation and synthesis of proteins with the help of transfer RNA (tRNA) and other factors. Not all RPs are indispensable; in other words, the ribosome could be functional and could continue the translation of proteins instead of lacking in some of the RPs. However, the lack of many RPs could result in severe defects in the biogenesis of ribosomes, which could directly influence the overall translation processes and global expression of the proteins leading to the emergence of different diseases including cancer. While microRNAs (miRNAs) are small non-coding RNAs and one of the potent regulators of the post-transcriptional gene expression, miRNAs regulate gene expression by targeting the 3' untranslated region and/or coding region of the messenger RNAs (mRNAs), and by interacting with the 5' untranslated region, and eventually finetune the expression of approximately one-third of all mammalian genes. Herein, we highlighted the significance of miRNAs mediated regulation of RPs coding mRNAs in the global protein translation.

Altered expression of microRNA-92b-3p predicts survival outcomes of patients with prostate cancer and functions as an oncogene in tumor progression

The global incidence of prostate cancer (PCa) has been increasing in recent years. Meanwhile, some studies have indicated the association between malignancies, such as lung and gastric cancer and PCa, and microRNAs (miRNAs). The present study was designed to assess the prognostic value of miR-92b-3p in patients with PCa and further investigate the biological function of miR-92b-3p. Real-time quantitative polymerase chain reaction was used to estimate the expression of miR-92b-3p in PCa tissues and cell lines compared with normal tissues and cells. Kaplan-Meier method was used to analyze the overall survival rate of patients with PCa. A Cox regression analysis was used to verify the prognostic value of miR-92b-3p. The biological function of miR-92b-3p was investigated using cell experiments. The findings of the present study revealed the upregulated expression of miR-92b-3p in PCa tissues and cells compared with normal tissues and cells. The overexpression of miR-92b-3p was significantly associated with the distant metastasis status and Tumor-Node-Metastasis stage of patients with PCa and predicted poor prognosis of PCa. In addition, the cell experiment results indicated that miR-92b-3p overexpression in PCa cells promoted cell proliferation, migration and invasion. The present study revealed that the overexpression of miR-92b-3p predicted poor prognosis in patients with PCa. Decreased expression of miR-92b-3p can suppress PCa cell proliferation, migration and invasion, which indicated that miR-92b-3p may function as an oncogene and serve as a novel therapeutic target for PCa.

MiR-92b-3p inhibits proliferation and migration of C2C12 cells

Skeletal muscle, a critical component of the mammalian body, is essential for normal body movement. miRNAs are well documented in gene post-transcription regulation in many biological processes, including muscle development and maintenance. miR-92b-3p, which is often associated with tumorigenesis, has never been explored in myoblast development. Here, we used murine-derived C2C12 myoblasts to explore the potential functions of miR-92b-3p in skeletal muscle development. Our results demonstrated that miR-92b-3p mimics inhibited C2C12 cell proliferation and migration, whereas miR-92b-3p inhibitor promoted C2C12 cell proliferation and migration. C2C12 cell differentiation was not affected by miR-92b-3p mimics, according to immunofluorescence and qPCR results. Serum- and glucocorticoid-induced kinase 3 (SGK3) was predicted and validated as a target of miR-92b-3p. Overexpression of SGK3 promoted C2C12 cell proliferation. SGK3 and miR-92b-3p formed a regulatory pathway to modulate C2C12 cell proliferation. In conclusion, miR-92b-3p inhibited C2C12 cell proliferation by targeting SGK3 and impeded C2C12 cell migration.

Expression of miRNAs in plasma exosomes derived from patients with atrial fibrillation

BACKGROUND

Studies have revealed the association between exosomes and cardiovascular diseases. However, the typical changes of plasma miRNAs in patients with atrial fibrillation (AF) are still controversial, the use of exosomal miRNAs to diagnose and predict the prognosis of AF has not been described.

HYPOTHESIS

We hypothesized that there were differences in the exosomal miRNAs between AF and normal sinus rhythm (SR) patients, which might be used as the novel biomarkers to reflect the progression of AF.

METHODS

miRNAs were isolated from the plasma of patients, and the target genes of differential miRNAs via enrichment analysis to discover potential pathogenesis related to AF. Combined with high-throughput sequencing results, real-time PCR was used to verify the relative expression of target miRNAs in patients.

RESULTS

This study confirmed that the expression of plasma-derived exosomal miRNAs between patients with AF and SR were different. Target gene enrichment analysis suggested that the target genes of 20 miRNAs, which were significantly upregulated were mainly enriched in biological processes such as gene expression process, inflammation response, enzyme modification, etc. Meanwhile, mitogen-activated protein kinase (MAPK), mammalian target of rapamycin (mTOR), and other pathways were highly enriched. The expressions of miR-92b-3p, miR-1306-5p, and miR-let-7b-3p had differences between patients with AF and SR.

CONCLUSION

These miRNAs and target genes were involved in the process of AF through affecting biological processes such as energy metabolism, lipid metabolism, inflammation, and enzyme activity. It suggested that the exosomal miRNAs might be used as the novel biomarkers to reflect the progression of AF.

Homeobox proteins are potential biomarkers and therapeutic targets in gastric cancer: a systematic review and meta-analysis

BACKGROUND

An increasing number of studies have described the aberrant expression of homeobox (HOX) proteins in gastric cancer (GC), which is critically associated with the prognosis and clinicopathological characteristics of GC. This study was conducted to investigate the clinical value and action mechanisms of HOX proteins in GC.

METHODS

A comprehensive search of PubMed, Embase, Web of Science and Cochrane Library was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. The pooled hazard ratio (HR) with its 95% confidence interval (95% CI) and the pooled odds ratio (OR) with its 95% CI were used to assess the effect of HOX protein expression on the prognosis and clinicopathological features of GC, respectively.

RESULTS

Nineteen studies containing 3775 patients were selected for this study. Heterogeneity among HRs of overall survival (OS) was markedly high (I2 = 90.5%, p = 0.000). According to the subgroup analysis, increased expression of HOX protein in the downregulated subgroup was associated with a good prognosis for patients with GC (pooled HR: 0.46, 95% CI: 0.36-0.59, I2 = 3.1%, p = 0.377), while overexpression of HOX protein in the upregulated subgroup was correlated with a reduced OS (pooled HR: 2.59, 95% CI: 1.79-3.74, I2 = 73.5%, p = 0.000). The aberrant expression of HOX protein was crucially related to the TNM stage, depth of tumour invasion, tumour size, lymph node metastasis, distant metastasis, vascular invasion, histological differentiation and Lauren classification in patients with GC. In addition, the molecular mechanisms by which HOX proteins regulate tumorigenesis and development of GC were also explored.

CONCLUSIONS

HOX proteins play vital roles in GC progression, which might serve as prognostic markers and therapeutic targets for GC.

Circulating miR-92b and miR-375 for monitoring the chemoresistance and prognosis of small cell lung cancer

miRNAs have been reported to be stably detectable in plasma and to function as potent biomarkers in multiple cancers. The study aimed to evaluate the expression of candidate circulating miRNAs in patients with small cell lung cancer (SCLC) to identify potential noninvasive biomarkers. The expression of five miRNAs (miR-92b, miR-146a, miR-375, miR-1224, and miR-1246) was significantly upregulated in plasma after chemoresistance induction. Receiver operating characteristic curve (ROC) analysis showed that the area under the curve (AUC) values of miR-92b and miR-375 were 0.766 and 0.791, respectively. The data demonstrated that among the five miRNAs assessed, these two miRNAs had better diagnostic accuracy for monitoring drug resistance. In addition, miR-92b and miR-375 levels were decreased after effective chemotherapy. Furthermore, Kaplan–Meier survival analysis confirmed that high expression of miR-92b and miR-375 was closely related to shorter progression-free survival (PFS) in SCLC patients. In conclusion, these findings indicate that circulating miR-92b and miR-375 might be ideal noninvasive biomarkers for monitoring drug resistance during chemotherapy and evaluating the prognosis of patients with SCLC.

Deoxycholic acid modulates the progression of gallbladder cancer through N6-methyladenosine-dependent microRNA maturation

Bile acids (BAs), well-defined signaling molecules with diverse metabolic functions, play important roles in cellular processes associated with many cancers. As one of the most common BAs, deoxycholic acid (DCA) is originally synthesized in the liver, stored in the gallbladder, and processed in the gut. DCA plays crucial roles in various tumors; however, functions and molecular mechanisms of DCA in gallbladder cancer (GBC) still remain poorly characterized. Here, we analyzed human GBC samples and found that DCA was significantly downregulated in GBC, and reduced levels of DCA was associated with poor clinical outcome in patients with GBC. DCA treatment impeded tumor progression by halting cell proliferation. DCA decreased miR-92b-3p expression in an m6A-dependent posttranscriptional modification manner by facilitating dissociation of METTL3 from METTL3-METTL14-WTAP complex, which increased the protein level of the phosphatase and tensin homolog, a newly identified target of miR-92b-3p, and subsequently inactivated the PI3K/AKT signaling pathway. Our findings revealed that DCA might function as a tumor suppressive factor in GBC at least by interfering with miR-92b-3p maturation, and suggested that DCA treatment could provide a new therapeutic strategy for GBC.

Frequent promoter methylation of HOXD10 in endometrial carcinoma and its pathological significance

Homeobox D 10 (HOXD10) is important in cell differentiation and morphogenesis and serves as a tumor suppressor gene (TSG) in a number of malignancies. The present study investigated its promoter methylation status and association with the clinicopathological features of endometrial cancer (EC), and measured HOXD10 protein expression levels. EC samples (n=62), including 50 endometroid adenocarcinoma (EA) and 12 mucinous endometrial carcinoma samples (EC) and 70 non-cancerous samples were collected. All samples were evaluated for the methylation status of several TSGs, including HOXD10, using methylation-specific PCR. HOXD10 expression level was evaluated using immunohistochemistry. 5-Aza-2-deoxycytidine treatment was performed in the EC cell line Ishikawa to observe the change in HOXD10 expression levels. HOXD10 promoter methylation was more frequent in cancer samples (P<0.001). Downregulation of HOXD10 in EC samples was confirmed at the protein level using immunohistochemistry (P<0.001) and immunohistochemical staining was negatively associated with methylation status (P<0.05). Less HOXD10 protein was expressed in MEC compared with EA samples (P<0.001). The HOXD10 promoter was hypermethylated in both EA and MEC, causing decreased HOXD10 protein expression levels in EC cells. HOXD10 expression levels were partially reversed by 5-Aza-2-deoxycytidine treatment. The results of the present study demonstrated that epigenetic silencing of HOXD10 putatively contributed to the tumorigenesis of EA. Although there was no significant difference in HOXD10 methylation between EA and MEC, HOXD10 protein expression levels differed between these two diseases, indicating that it may be a useful protein biomarker for distinguishing between these two lesions.

Expression and significance of urinary microRNA in patients with chronic hepatitis B

The aim of this study was to investigate the alterations of urinary microRNA (miRNA) expression and explore its clinical significance in patients with chronic hepatitis B (CHB).The expression levels of urinary miRNA were detected by miRNA microarray and quantitative reverse transcription polymerase chain reaction (qRT-PCR) from 106 CHB and 40 healthy controls (Ctrl) subjects. The correlation between the levels of miRNA expression and clinical characteristics were analyzed. Receiver-operator characteristic (ROC) curves were generated to determine the specificity and sensitivity of each individual miRNA. MiRNAs expression were further measured by PCR from exosomes, which were isolated from urine samples. LX2 cells were transfected with miRNA inhibitor and accumulation of cytoplasmic lipid droplets was analyzed by Oil Red O staining.miRNA expression profile analysis showed that 22 miRNAs were upregulated and 55 miRNAs were downregulated in CHB patients compared with Ctrl subjects (fold-change>1.5 and P < .05). miR-92b-3p, miR-770-5p, miR-5196-5p, and miR-7855-5p were significantly higher (P < .0001) in CHB subjects than in Ctrl subjects. ROC curve analysis showed that these four miRNAs were sensitive and specific enough to distinguish CHB and Ctrl subjects. The levels of miR-92b-3p expression were negatively correlated with total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and APOA-1. Moreover, in vitro experiments indicated that inhibition of miR-92b-3p increased lipid droplet formation in LX2 cells.Aberrant expression of miRNAs has been observed in urine of CHB patients. Our findings may provide novel insights into the pathogenesis of CHB and may assist in the diagnosis of patients with CHB.