The lncRNA PDIA3P Interacts with miR-185-5p to Modulate Oral Squamous Cell Carcinoma Progression by Targeting Cyclin D2

Long noncoding RNAs (lncRNAs) are emerging as important regulators during tumorigenesis by serving as competing endogenous RNAs (ceRNAs). In this study, the qRT-PCR results indicated that the lncRNA protein disulfide isomerase family A member 3 pseudogene 1 (PDIA3P) was overexpressed in oral squamous cell carcinoma (OSCC) and decreased the survival rate of OSCC patients. CCK-8 and clonal colony formation assays were used to detect the effects of PDIA3P on proliferation. Results revealed that silencing PDIA3P by small interfering RNA (siRNA) inhibited OSCC cell proliferation and repressed tumor growth and reduced the expression of proliferation antigen Ki-67 in vivo. Furthermore, the interaction between PDIA3P and miRNAs was then analyzed by qRT-PCR and luciferase reporter gene assay. We found that PDIA3P negatively regulated miR-185-5p in OSCC cells. Simultaneously, we found that silencing PDIA3P by siRNA suppressed proliferation via miR-185-5p in OSCC cells. Moreover, silencing PDIA3P by siRNA inhibited CCND2 protein (no influence on mRNA levels) expression via miR-185-5p in OSCC cells, and CCND2 facilitated cell proliferation of SCC4 and SCC15 cells induced by sh-PDIA3P#1. Therefore, our study demonstrated that PDIA3P may be a therapeutic target for the treatment of OSCC.

lncRNA KLF3-AS1 Suppresses Cell Migration and Invasion in ESCC by Impairing miR-185-5p-Targeted KLF3 Inhibition

Esophageal squamous cell carcinoma (ESCC) is a common cancer occurring in males and females worldwide. Accumulating evidence continues to highlight the crucial roles of long non-coding RNAs (lncRNAs) in the process of tumorigenesis. However, the regulatory mechanism of lncRNAs in ESCC remains unclear. The aim of this study is to elucidate the role of lncRNA Krüppel-like factor 3 antisense RNA 1 (KLF3-AS1) in ESCC by regulating miR-185-5p and KLF3. Initially, ESCC cell spheres with stem cell-like properties were prepared by suspension culture, and subsequently characterized by assessing colony formation ability and stem cell markers. LncRNA KLF3-AS1 was found to be poorly expressed in ESCC and could upregulate the expression of KLF3 by binding to miR-185-5p. lncRNA KLF3-AS1 upregulation was observed to inhibit miR-185-5p, thereby contributing to decreased expression of SOX2 and Oct4 (octamer-binding transcription factor 4). Furthermore, enhancement of lncRNA KLF3-AS1 resulted in reduced colony formation ability, cell invasion and migration, and tumor volume in vivo while promoting cell apoptosis in ESCC through downregulation of miR-185-5p. Collectively, this study indicated that lncRNA KLF3-AS1 inhibited ESCC cell invasion and migration by impairing miR-185-5p-mediated inhibition of KLF3, highlighting a promising novel potential target for ESCC treatment.

Lnc HAGLR Promotes Colon Cancer Progression Through Sponging miR-185-5p and Activating CDK4 and CDK6 in vitro and in vivo

BACKGROUND/AIM

LncRNA plays a key role in tumor progression. HAGLR functions as an oncogene in many cancers. However, the molecular mechanism of HAGLR in colon cancer is still unclear.

METHODS

qRT-PCR was used to measure the expression of HAGLR, miR-185-5p in colon cancer. The expression of CDK4 and CDK6 was detected by Western blot. CCK-8 assay, EdU staining, transwell and Annexin V-FITC/PI assay were used to analyze the effect of HAGLR and miR-185-5p on cell proliferation, invasion, migration and apoptosis. Bioinformatic analysis and luciferase were used to analyze the target genes of HAGLR and miR-185-5p. Nude mice were used to detect mouse tumor changes.

RESULTS

Compared with normal colon cancer tissues and cells, the expression of HAGLR was increased in colon cancer tissues and cells. In addition, the expression of HAGLR down-regulation inhibited the growth, migration, and invasion of colon cancer cells. MiR-185-5p was reduced in colon cancer, and CDK4 and CDK6 acted as target genes of miR-185-5p to regulate the progress of colon cancer. And CDK4 and CDK6 were predicted as downstream targets of miR-185-5p. Finally, it was demonstrated that HAGLR regulated tumor progression in vivo.

CONCLUSION

Lnc HAGLR promoted the development of colon cancer by miR-185-5p/CDK4/CDK6 axis, and lnc HAGLR might be potential target for colon cancer.

LncRNA MALAT1 accelerates non-small cell lung cancer progression via regulating miR-185-5p/MDM4 axis

Non-small cell lung cancer (NSCLC) is the commonest malignancy with high death rate around the world. LncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is greatly overexpressed in multifarious cancers, including NSCLC. However, the precise mechanism of MALAT1 in NSCLC tumorigenesis is blurry. This paper aims to investigate the theory of MALAT1 action in NSCLC progression. The levels of MALAT1, microRNA (miR)-185-5p, and mouse double minute 4 protein (MDM4) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell proliferation and apoptosis were, respectively, determined by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and flow cytometry. Cell migratory and invasive abilities were inspected by transwell assay. The binding relationship between miR-185-5p and MALAT1 or MDM4 was confirmed by dual-luciferase reporter assay. The impacts of MALAT1 on tumor growth in vivo were measured by a xenograft experiment. We found MALAT1 and MDM4 were upregulated and MALAT1 positively regulated the MDM4 expression. MALAT1 and MDM4 deletion significantly hindered the proliferation, metastasis, and expedited the apoptosis of NSCLC cells. MDM4 overexpression partly overturned the influence of MALAT1 downregulation on cell development. Moreover, miR-185-5p, as a target of MALAT1, could directly target MDM4, and miR-185-5p upregulation exerted inhibitory effects on NSCLC cells. Besides, knockdown of MALAT1 inhibited tumor growth in vivo through miR-185-5p/MDM4 axis in NSCLC. Collectively, MALAT1 contributed to proliferation, migration, invasion, and impeded apoptosis by regulating the MDM4 expression mediated by miR-185-5p in NSCLC cells.

Circ_WBSCR17 aggravates inflammatory responses and fibrosis by targeting miR-185-5p/SOX6 regulatory axis in high glucose-induced human kidney tubular cells

BACKGROUND

Diabetic nephropathy (DN), a severe microvascular complication of diabetes, has complex pathogenesis. Circular RNAs (circRNAs) exert broad biological functions on human diseases. This study intended to explore the role and mechanism of circ_WBSCR17 in DN.

METHODS

DN mice models were constructed using streptozotocin injection, and DN cell models were assembled using high glucose (HG) treatment in human kidney 2 cells (HK-2). The expression of circ_WBSCR17, miR-185-5p and SRY-Box Transcription Factor 6 (SOX6) was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein levels of SOX6 and fibrosis markers were examined by western blot. The release of inflammatory cytokines, cell proliferation and apoptosis, were assessed by enzyme-linked immunosorbent assay (ELISA), cell counting kit-8 (CCK-8) assay and flow cytometry assay, respectively. The predicted interaction between miR-185-5p and circ_WBSCR17 or SOX6 was verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay.

RESULT

Circ_WBSCR17 was highly expressed in DN mice models and HG-induced HK-2 cells. Circ_WBSCR17 knockdown or SOX6 knockdown promoted cell proliferation and blocked cell apoptosis, inflammatory responses and fibrosis, while circ_WBSCR17 overexpression or SOX6 overexpression conveyed the opposite effects. MiR-185-5p was a target of circ_WBSCR17 and directly bound to SOX6. MiR-185-5p could reverse the role of circ_WBSCR17 or SOX6. Moreover, the expression of SOX6 was modulated by circ_WBSCR17 through intermediating miR-185-5p.

CONCLUSION

Circ_WBSCR17 triggered the dysfunction of HG-induced HK-2 cells, including inflammatory responses and fibrosis, which was accomplished via the miR-185-5p/SOX6 regulatory axis.

Knockdown of lncRNA PCAT6 Enhances Radiosensitivity in Triple-Negative Breast Cancer Cells by Regulating miR-185-5p/TPD52 Axis

Background

Long non-coding RNAs (lncRNAs) have been reported to play essential roles in regulating the radiosensitivity of cancers. Prostate cancer-associated transcript 6 (PCAT6) exerts oncogenic roles in several tumors. However, the roles of PCAT6 and its underlying mechanism in regulating the radiosensitivity of triple-negative breast cancer (TNBC) have not been investigated.

Methods

The expression levels of PCAT6, microRNA-185-5p (miR-185-5p) and tumor protein D52 (TPD52) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability, apoptosis and colony formation were assessed by Cell Counting Kit-8 (CCK-8) assay, flow cytometry and colony formation assay, respectively. The interaction between miR-185-5p and PCAT6 or TPD52 was predicted by bioinformatics analysis and verified by dual-luciferase reporter assay. Western blot was carried out to detect the protein level of TPD52.

Results

PCAT6 and TPD52 were highly expressed and miR-185-5p was lowly expressed in TNBC tissues and cells, which was associated with an aggressive tumor phenotype in patients, affecting lymph node metastasis and clinical stage. PCAT6 or TPD52 knockdown or miR-185-5p overexpression enhanced the radiosensitivity of TNBC cells via inhibiting proliferation and inducing apoptosis. PCAT6 directly interacted with miR-185-5p and negatively regulated miR-185-5p expression. Moreover, TPD52 was confirmed as a target of miR-185-5p. Besides, PCAT6 regulated the radiosensitivity of TNBC cells through acting as a molecular sponge of miR-185-5p to modulate TPD52 expression.

Conclusion

Knockdown of PCAT6 promoted the radiosensitivity of TNBC cells through regulating miR-185-5p/TPD52 axis, providing a vital theoretical basis to improve the radiotherapy efficiency of TNBC.

LncRNA RNCR3 promotes Chop expression by sponging miR-185-5p during MDSC differentiation

Myeloid-derived suppressor cells (MDSCs) play a critical role in regulating immune responses in cancer and other pathological conditions. Mechanism(s) regulating MDSC differentiation and function is not completely clear, especially epigenetic regulation. In this study, we found that MDSCs express retinal non-coding RNA3 (RNCR3), and the expression in MDSCs is upregulated by inflammatory and tumor associated factors. RNCR3 may function as a competing endogenous RNA (ceRNA) to promote Chop expression by sponging miR-185-5p during MDSC differentiation. RNCR3 knockdown suppressed differentiation and function of MDSCs in vitro and in vivo. Quantitative RT-PCR showed that RNCR3 was negatively regulated by miR-185-5p in MDSCs. MiR-185-5p affected the expansion of MDSCs and reversed the effect of RNCR3 on MDSC differentiation and function through directly targeting Chop. Thus, our results suggest a RNCR3/miR-185-5p/Chop autologously strengthening network to promote MDSC differentiation and suppressive function in response to extracellular inflammatory and tumor-associated signals.

Long noncoding RNA FOXD2-AS1 promotes glioma malignancy and tumorigenesis via targeting miR-185-5p/CCND2 axis

Glioma is the most aggressive malignant tumor in the adult central nervous system. Abnormal long noncoding RNA (lncRNA) FOXD2-AS1 expression was associated with tumor development. However, the possible role of FOXD2-AS1 in the progression of glioma is not known. In the present study, we used in vitro and in vivo assays to investigate the effect of abnormal expression of FOXD2-AS1 on glioma progression and to explore the mechanisms. FOXD2-AS1 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of FOXD2-AS1 was correlated with poor prognosis of glioma. Downregulation of FOXD2-AS1 decreased cell proliferation, migration, invasion, stemness, and epithelial-mesenchymal transition (EMT) in glioma cells and inhibited tumor growth in transplanted tumor. We also revealed that FOXD2-AS1 was mainly located in cytoplasm and microRNA (miR)-185-5p both targeted FOXD2-AS1 and CCND2 messenger RNA (mRNA) 3'-untranslated region (3'-UTR). miR-185-5p was downregulated in glioma tissue, cells, and sphere subpopulation. Downregulation of miR-185-5p was closely correlated with poor prognosis of glioma patients. In addition, miR-185-5p mimics decreased cell proliferation, migration, invasion, stemness, and EMT in glioma cells. CCND2 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of CCND2 was closely correlated with poor prognosis of glioma patients. CCND2 knockdown decreased cell proliferation, migration, invasion, and EMT in glioma cells. In glioma tissues, CCND2 expression was negatively associated with miR-185-5p, but positively correlated with FOXD2-AS1. FOXD2-AS1 knockdown and miR-185-5p mimics decreased CCND2 expression. Inhibition of miR-185-5p suppressed FOXD2-AS1 knockdown-induced decrease of CCND2 expression. Overexpression of CCND2 suppressed FOXD2-AS1 knockdown-induced inhibition of glioma malignancy. Taken together, our findings highlight the FOXD2-AS1/miR-185-5p/CCND2 axis in the glioma development.

LncRNA NEAT1/miR-185-5p/IGF2 axis regulates the invasion and migration of colon cancer

Background

Long noncoding RNAs (lncRNA) are important in the growth and metastasis of colon cancer. The objective of this study was to describe the potential role of lncRNA NEAT1 in the progression of colon cancer.

Methods

Quantitative real‐time polymerase chain reaction was used for detecting NEAT1, miR‐185‐5p, and IGF2 in colon cancer cells and tissues. The potential diagnostic value of NEAT1 in colon cancer was analyzed with the receiver operating characteristic curve. Kaplan–Meier method was applied for evaluating the association between NEAT1 expression and the overall survival of osteosarcoma patients, whereas Transwell assay was introduced to examine the potential invasion and migration of colon cancer cells. In addition, the binding of NEAT1/IGF2 to miR‐185‐5p was confirmed by RNA pull‐down and RNA‐binding protein immunoprecipitation assays and dual‐luciferase reporter gene assay. Finally, rescue experiments were conducted to confirm the role of NEAT1/miR‐185‐5p/IGF2 axis in colon cancer.

Results

Colon cancer patients with low NEAT1 expression presented with longer overall survival than those with high expression. The migration and invasion of colon cancer cells were considerably promoted by overexpressed NEAT1. Both NEAT1 and IGF2 bound to miR‐185‐5p.

Conclusion

NEAT1 upregulate IGF2 expression through absorbing miR‐185‐5p to enhances the migration and invasion of colon cancer cells.

miR-185-5p targets ROCK2 and inhibits cell migration and invasion of hepatocellular carcinoma

Previous studies demonstrated microRNA-185 (miR-185) as a tumor suppressive microRNA (miRNA) in various types of cancer. The current study aimed to verify this finding in hepatocellular carcinoma (HCC) and explored the downstream channel of miR-185-5p. We detected miR-185-5p and Rho-associated coiled-coil containing protein kinase 2 (ROCK2) mRNA and protein levels by reverse transcription-quantitative PCR (RT-qPCR) and western blotting in HCC tissues and cell lines. Luciferase reporter assay proved the direct relationship between miR-185-5p and ROCK2. Cell migration and invasion were assessed via Transwell assay. miR-185-5p level was reduced in HCC tissues and cell lines. miR-185-5p overexpression impeded migration and invasion of HCC cells. Moreover, miR-185-5p directly targeted ROCK2 which was repressed by miR-185-5p in HCC. In addition, ROCK2 contributed to cell metastasis of HCC. In summary, miR-185-5p inhibited cell metastasis of HCC by suppressing ROCK2. The novel miR-185/ROCK2 axis shows potential in improving the therapies of HCC and enhancing HCC survival.

RETRACTED: Long non-coding RNA UCA1 targets miR-185-5p and regulates cell mobility by affecting epithelial-mesenchymal transition in melanoma via Wnt/β-catenin signaling pathway

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Several figures presented in the manuscript appear to have been doctored. The journal has tried to contact the authors of this article but at the time of publication of this notice has not received any response. As there is no explanation for the picture manipulations, the Editor-in-Chief of Gene has lost confidence in the validity of this work and has decided to retract it.

Down-regulated PLAC8 promotes hepatocellular carcinoma cell proliferation by enhancing PI3K/Akt/GSK3β/Wnt/β-catenin signaling

Hepatocellular carcinoma (HCC) is a common, prevalent malignancy. Its poor prognosis is mainly related to high rate of diagnosis in non-curable stages, in which patients are suitable for palliative treatment. Placenta-specific 8 (PLAC8), also known as Onzin, is a small, highly conserved, cysteine-rich protein. In current study, we found that PLAC8 is prominently decreased in HCC tissues compared with adjacent tissues and patients with low level of PLAC8 suffered a poor prognosis. In addition, cellular function assays demonstrate that down-regulated PLAC8 promotes cell viability, proliferation and tumor formation both in vitro and in vivo. Furthermore, we validate that down-regulated PLAC8 enhances the activity of PI3K/Akt/GSK3β and Wnt/β-catenin signaling to promote cell proliferation. Moreover, we proved that highly expressed miR-185-5p targets PLAC8 in HCC tissues. In conclusion, our findings enlarged our knowledge about the roles of PLAC8 in HCC progression and miR-185-5p/PLAC8/β-catenin axis might be a novel pathway for HCC treatment.

Long noncoding RNA LINC00958 promotes the oral squamous cell carcinoma by sponging miR-185-5p/YWHAZ

AIM

Increasing evidence has indicated the essential roles of long noncoding RNA (lncRNA) in the oral squamous cell carcinoma (OSCC). However, there are still numerous uncertain mechanisms for the pathophysiological process of OSCC. In this work, we tried to identify the biological function and potential mechanism of lncRNA LINC00958 in the OSCC.

MAIN METHODS

The expressions of RNA and protein were measured by quantitative real-time polymerase chain reaction (RT-qPCR) and western blotting. The tumor behavior was detected using the CCK-8 assay, transwell assay, flow cytometry assay and xenograft in vivo assay. The interaction within LINC00958/miR-185-5p/YWHAZ was identified using the luciferase reporter assay.

KEY FINDINGS

LINC00958 expression was remarkably up-regulated in the OSCC tissue and cell lines. Clinical investigation showed that LINC00958 overexpression was associated with poor prognosis, acting as an independent prognostic factor for OSCC. Loss- and gain-of-function assays indicated that LINC00958 promoted the proliferation, invasion and reduced the apoptosis of OSCC cells in vitro. In vivo, knockdown of LINC00958 repressed the tumor growth. Mechanistically, bioinformatic tools and luciferase reporter assay indicated that miR-185-5p both targeted the 3'-UTR of LINC00958 and YWHAZ, constructing the LINC00958/miR-185-5p/YWHAZ regulatory axis.

SIGNIFICANCE

Taken together, the findings in this research reveal the modulation of LINC00958 for the OSCC tumorigenesis through the miR-185-5p/YWHAZ axis, which might be useful for the mechanical investigation associated with OSCC therapeutic target.

lncRNA H19 promotes matrix mineralization through up-regulating IGF1 by sponging miR-185-5p in osteoblasts

Background

Matrix mineralization is a key stage in bone formation involving in many bone-specific genes and signaling pathways. Emerging evidence indicate that long non-coding RNA (lncRNA) and microRNAs (miRNAs) play crucial roles in regulating the mineralization process of osteoblasts. This study aims to characterize the function and mechanism of lncRNA H19/miR-185-5p/IGF1 axis in modulating matrix mineralization of osteoblasts.

Results

H19 and IGF1 were highly expressed while miR-185-5p was lowly expressed in mineralized cells. Knocking down H19 inhibited matrix mineralization of osteoblasts, yet miR-185-5p had opposite effects. Moreover, H19 directly targeted miR-185-5p, whereas miR-185-5p repressed IGF1 expression. Meanwhile, miR-185-5p inhibition compensated the suppression of the matrix mineralization in osteoblasts by H19 knockdown.

Conclusions

The findings of this study showed that lncRNA H19 was upregulated in mineralized osteoblasts and promoted matrix mineralization through miR-185-5p/IGF1 axis in osteoblasts for the first time. This study may provide a new perspective for the diagnosis and treatment of diseases related to bone metabolism.

Long noncoding RNA NEAT1 promotes progression of glioma as a ceRNA by sponging miR-185-5p to stimulate DNMT1/mTOR signaling

Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) is regarded as an oncogene in multiple cancers. Previous studies have shown that NEAT1 is involved in the proliferation and tumorigenesis of glioma cells, while miR-185-5p functions as a tumor suppressor in glioma. However, the underlying molecular mechanism of NEAT1 in glioma, especially in association with miR-185-5p, has not been studied. In this study, we first demonstrated that NEAT1 expression was upregulated, and miR-185-5p downregulated in glioma tissues and cells. More important, NEAT1 expression was negatively correlated with miR-185-5p expression in glioma tissues. In vitro and in vivo experiments verified that NEAT1 was a competing endogenous RNA for miR-185-5p for promoting DNA methyltransferase 1 (DNMT1) expression and activated mammalian target of rapamycin (mTOR) signaling, thus inhibiting apoptosis, and promoting glioma migration, proliferation, and epithelial-mesenchymal transition process. Furthermore, NEAT1 knockdown suppressed tumor growth and reduced the expression of proliferation antigen Ki-67, DNMT1, and mTOR, but upregulated the expression of miR-185-5p in vivo. Finally, with mTOR inhibitor rapamycin, we confirmed that NEAT1 promoted glioma activity through mTOR signaling both in vitro and in vivo. In conclusion, these results suggest that NEAT1 promotes glioma tumorigenesis via miR-185-5p/DNMT1/mTOR signaling, which may provide a new target for the diagnosis and therapy of glioma.

miR-185-5p response to usnic acid suppresses proliferation and regulating apoptosis in breast cancer cell by targeting Bcl2

BACKGROUND

Breast cancer is the most common cancer types among women. Recent researches have focused on determining the efficiency of alternative molecules and miRNAs in breast cancer treatment. The aim of this study was to determine the effect of usnic acid response-miR-185-5p on proliferation in the breast cancer cell and to determine its relationship with apoptosis pathway.

METHODS

The cell proliferation and cell apoptosis rate were significantly increased following the ectopic expression of miR-185-5p in BT-474 cells. Furthermore, the results of cell cycle assay performed by flow cytometry revealed that the transfection with miR-185-5p induced G1/S phase arrest. The apoptosis-related genes expression analysis was performed by qRT-PCR and the direct target of miR-185-5p in BT-474 cells was identified by western blot and luciferase reporter assay.

RESULTS

Our data showed that miR-185-5p can cause significant changes in apoptosis-related genes expression levels, suggesting that cell proliferation was suppressed by miR-185-5p via inducing apoptosis in breast cancer cells. According to western blot results, miR-185-5p lead to decrease BCL2 protein level in BT-474 cells and direct target of miR-185-5p was identified as BCL by luciferase reporter assay.

CONCLUSION

This study revealed that miR-185-5p may be an effective agent in the treatment of breast cancer.

MicroRNA-185-5p mediates regulation of SREBP2 expression by hepatitis C virus core protein

AIM: To investigate the molecular mechanism for regulation of cholesterol metabolism by hepatitis C virus (HCV) core protein in HepG2 cells.

METHODS: HCV genotype 1b core protein was cloned and expressed in HepG2 cells. The cholesterol content was determined after transfection. The expression of sterol regulatory element binding protein 2 (SREBP2) and the rate-limiting enzyme in cholesterol synthesis (HMGCR) was measured by quantitative real-time PCR and immunoblotting after transfection. The effects of core protein on the SREBP2 promoter and 3’-untranslated region were analyzed by luciferase assay. We used different target predictive algorithms, microRNA (miRNA) mimics/inhibitors, and site-directed mutation to identify a putative target of a particular miRNA.

RESULTS: HCV core protein expression in HepG2 cells increased the total intracellular cholesterol level (4.05 ± 0.17 vs 6.47 ± 0.68, P = 0.001), and this increase corresponded to an increase in SREBP2 and HMGCR mRNA levels (P = 0.009 and 0.037, respectively) and protein expression. The molecular mechanism study revealed that the HCV core protein increased the expression of SREBP2 by enhancing its promoter activity (P = 0.004). In addition, miR-185-5p expression was tightly regulated by the HCV core protein (P = 0.041). Moreover, overexpression of miR-185-5p repressed the SREBP2 mRNA level (P = 0.022) and protein expression. In contrast, inhibition of miR-185-5p caused upregulation of SREBP2 protein expression. miR-185-5p was involved in the regulation of SREBP2 expression by HCV core protein.

CONCLUSION: HCV core protein disturbs the cholesterol homeostasis in HepG2 cells via the SREBP2 pathway; miR-185-5p is involved in the regulation of SREBP2 by the core protein.

Exosomal ncRNAs profiling of mycobacterial infection identified miRNA-185-5p as a novel biomarker for tuberculosis

BACKGROUND

There are ever increasing researches implying that noncoded RNAs (ncRNAs) specifically circular RNAs (circRNAs) and microRNAs (miRNAs) in exosomes play vital roles in respiratory disease. However, the detailed mechanisms persist to be unclear in mycobacterial infection.

METHODS

In order to detect circRNAs and miRNAs expression pattern and potential biological function in tuberculosis, we performed immense parallel sequencing for exosomal ncRNAs from THP-1-derived macrophages infected by Mycobacterium tuberculosis H37Ra, Mycobacterium bovis BCG and control Streptococcus pneumonia, respectively and uninfected normal cells. Besides, THP-1-derived macrophages were used to verify the validation of differential miRNAs, and monocytes from PBMCs and clinical plasma samples were used to further validate differentially expressed miR-185-5p.

RESULTS

Many exosomal circRNAs and miRNAs associated with tuberculosis infection were recognized. Extensive enrichment analyses were performed to illustrate the major effects of altered ncRNAs expression. Moreover, the miRNA-mRNA and circRNA-miRNA networks were created and expected to reveal their interrelationship. Further, significant differentially expressed miRNAs based on Exo-BCG, Exo-Ra and Exo-Control, were evaluated, and the potential target mRNAs and function were analyzed. Eventually, miR-185-5p was collected as a promising potential biomarker for tuberculosis.

CONCLUSION

Our findings provide a new vision for exploring biological functions of ncRNAs in mycobacterial infection and screening novel potential biomarkers. To sum up, exosomal ncRNAs might represent useful functional biomarkers in tuberculosis pathogenesis and diagnosis.

MiR-185-5p suppresses HBV gene expression by targeting ELK1 in hepatoma carcinoma cells

AIMS

To investigate the role and underlying mechanism of miR-185-5p in hepatitis B virus (HBV) expression and replication.

MAIN METHODS

The relative levels of hepatitis B surface antigen and hepatitis B e antigen were detected by enzyme-linked immunosorbent assay (ELISA). The HBV DNA copies in the cultures medium were measured by RT-qPCR. The HBV large surface antigen promoter (S1p) activity was analyzed by luciferase reporter assay. The target relationship between miR-185-5p and ELK1 was identified by bioinformatics analysis and EGFP fluorescent reporter assay. The ELK1 expression was determined by RT-qPCR and Western blot.

KEY FINDINGS

miR-185-5p significantly decreased HBV large surface antigen promoter activity and subsequently the production of HBV proteins and HBV DNA copies in vitro. Further, we identified the ETS transcription factor ELK1 is a target of miR-185-5p. Overexpression and knockdown experiments showed overexpression of ELK1 stimulated HBV large surface antigen promoter activity and promoted the production of HBV proteins and HBV DNA copies, whereas knockdown of ELK1 has the opposite effects. Moreover, the rescue of ELK1 expression reversed the suppression of miR-185-5p on HBV replication and gene expression. Further mechanistic study showed that the ETS binding sites within the HBV large surface antigen promoter are required for the repression effect of miR-185-5p on HBV.

SIGNIFICANCE

There are few reports about the interaction between miRNAs and the transcription from HBV S1p, we found that miR-185-5p decreases HBV S1p activity by targeting ELK1, which may provide a promising therapeutic strategy for HBV infection.

KCNQ1OT1 promotes migration and inhibits apoptosis by modulating miR-185-5p/Rab14 axis in oral squamous cell carcinoma

Long non-coding RNAs (lncRNAs) play essential roles in the regulation of gene transcription in carcinogenesis and metastasis via interacting with microRNA. In this study, we explored the expressions and functions of lncRNA KCNQ1OT1 and miR-185-5p in oral squamous cell carcinoma (OSCC) cells. KCNQ1OT1 expression in OSCC tissues and cells was examined by qRT-PCR. Small interfering RNAs against KCNQ1OT1 (si- KCNQ1OT1) were used to knockdown KCNQ1OT1 in OSCC cells. Cell function was assessed by wound healing assay, transwell assay, and apoptosis detection. The binding region between KCNQ1OT1 and miR-185-5p was confirmed by luciferase assays. MiR-185-5p expression was measured by qRT-PCR. Rab14 was confirmed as a downstream target gene of miR-185-5p by measuring luciferase activities. The protein level of Rab14 in OSCC cells transfected with miR-185-5p or si-KCNQ1OT1 was determined by Western blot. The OSCC cell function and Rab14 expression after co-transfection of si-KCNQ1OT1 and miR-185-5p inhibitor were also examined. KCNQ1OT1 was upregulated in OSCC tissues and cells. KCNQ1OT1 silencing suppressed OSCC cell malignancy and downregulated miR-185-5p level, which showed upregulated expression in OSCC samples. Rab14 as a target gene of miR-185-5p was highly expressed in OSCC. KCNQ1OT1 knockdown impaired the invasion capability of OSCC cells, promoted apoptosis, and suppressed Rab14 expression. The inhibition of miR-185-5p in KCNQ1OT1 silencing cells reversed the suppression of Rab14 and restored the cancerous growth of OSCC cells. These results indicated that KCNQ1OT1 promoted OSCC tumorigenesis via the modulation of miR-185-5p/Rab14 axis, which may serve as a therapeutic target for the treatment of OSCC.

Circular RNA circUBR4 regulates ox-LDL-induced proliferation and migration of vascular smooth muscle cells through miR-185-5p/FRS2 axis

Circular RNAs (circRNAs) have been reported to play vital roles in atherosclerosis. However, the precise roles of circUBR4 in atherosclerosis remain unclear. The purpose of this study is to investigate the regulatory roles of circUBR4 in atherosclerosis. The expression levels of circUBR4, miR-185-5p, and Fibroblast growth factor receptor substrate 2 (FRS2) were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR) assay. Human vascular smooth muscle cells (VSMCs) were treated with oxidized low-density lipoprotein (ox-LDL) to mimic atherosclerosis condition in vitro. Cell proliferation was determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazol-3-ium bromide (MTT), colony-forming, and 5-ethynyl-2'-deoxyuridine (EdU) assays. Wound healing and transwell assays were used to assess cell migration. The interaction relationship between miR-185-5p and circUBR4 or FRS2 was confirmed by dual-luciferase reporter and RNA pull-down assays. CircUBR4 was overexpressed in atherosclerosis patients and VSMCs treated with ox-LDL, and the knockdown of circUBR4 abolished ox-LDL-induced enhanced effects on the proliferation and migration of VSMCs. MiR-185-5p, interacted with FRS2, was a target of circUBR4 in VSMCs. The silencing of miR-185-5p reversed the effects caused by circUBR4 knockdown on ox-LDL-induced VSMCs. In addition, overexpression of miR-185-5p suppressed the proliferation and migration of VSMCs by targeting FRS2. CircUBR4 contributed to ox-LDL-induced VSMC proliferation and migration through up-regulating FRS2 via miR-185-5p.

Long non-coding RNA DANCR accelerates colorectal cancer progression via regulating the miR-185-5p/HMGA2 axis

Long non-coding RNAs (lncRNAs) are crucial players in tumor progression. Herein, this work was designated to decipher the clinical significance, function and molecular mechanism of an lncRNA, differentiation antagonizing non-coding RNA (DANCR) in colorectal cancer (CRC). Quantitative real-time PCR (qRT-PCR) was adopted to examine DANCR, miR-185-5p and HMGA2 mRNA expressions in CRC tissues and cells. Both gain-of-function and loss-of-function cell models for DANCR were established, and then MTT, wound healing and Transwell, flow cytometry assays were carried out to detect the proliferation, migration, invasion, cell cycle and apoptosis of CRC cells. Dual luciferase reporter gene assay and RIP assay were utilized to validate the targeting relationships between DANCR and miR-185-5p. Western blot was employed for detecting high mobility group A2 (HMGA2) expressions in CRC cells. In this study, we demonstrated that the expression of DANCR was elevated in CRC tissues and cell lines, and its high expression was significantly associated with increased TNM stage and positive lymph node metastasis. DANCR overexpression promoted CRC cell proliferation, migration, invasion and cell cycle progression, but inhibited apoptosis; while knocking down DANCR caused the opposite effects. DANCR was further identified as a molecular sponge for miR-185-5p, and DANCR could indirectly increase the expression of HMGA2 via repressing miR-185-5p. In conclusion, DANCR/miR-185-5p/HMGA2 axis participated in the progression of CRC.

MicroRNAs Targeting HIF-2α, VEGFR1 and/or VEGFR2 as Potential Predictive Biomarkers for VEGFR Tyrosine Kinase and HIF-2α Inhibitors in Metastatic Clear-Cell Renal Cell Carcinoma

Metastatic clear-cell renal cell carcinoma (m-ccRCC) is characterized by increased hypoxia-induced factor (HIF)-2α and vascular endothelial growth factor receptor (VEGFR)-dependent angiogenesis through loss of function of the von Hippel-Lindau protein. VEGFR tyrosine kinase inhibitors (VEGFR-TKIs) are a cornerstone of m-ccRCC treatment, and new treatments targeting HIF-2α are currently under investigation. However, predictive biomarkers for these treatments are lacking. In this retrospective cohort study including 109 patients treated with VEGFR-targeted therapies as first-line treatment, we aimed to study the possible predictive function of microRNAs (miRNAs) targeting HIF-2α, VEGFR1 and VEGFR2. We selected miRNAs inversely correlated with HIF-2α, VEGFR1 and/or VEGFR2 expression and with predicted target sites in the respective genes and subsequently studied their impact on therapeutic outcomes. We identified four miRNAs (miR-34c-5p, miR-221-3p, miR-222-3p and miR-3529-3p) inversely correlated with VEGFR1 and/or VEGFR2 expression and associated with tumor shrinkage and progression-free survival (PFS) upon treatment with VEGFR-TKIs, highlighting the potential predictive value of these miRNAs. Moreover, we identified three miRNAs (miR-185-5p, miR-223-3p and miR-3529-3p) inversely correlated with HIF-2α expression and associated with tumor shrinkage and PFS upon treatment with VEGFR-TKIs. These three miRNAs can have a predictive value not only upon treatment with VEGFR-TKIs but possibly also upon treatment with the upcoming HIF-2α inhibitor belzutifan.

MiR-185-5p targets RAB35 gene to regulate tumor cell-derived exosomes-mediated proliferation, migration and invasion of non-small cell lung cancer cells

Introduction: Non-small cell lung cancer (NSCLC) is the most common malignant tumor, and its recurrence and metastasis are the main causes of death. Recently, there is evidence that tumor derived exosomes play an important role in the occurrence and development of NSCLC.

Objective’s methods: First, the expression of miR-185-5p and RAB35 in NSCLC tissues, paracancerous tissues, NSCLC cell lines and normal human bronchial epithelial cell line was detected. Then, a series of gain-and loss-of-function assays were performed to validate the effects of miR-185-5p or RAB35 effects on A549 and H2170 cells proliferation, migration and invasion. Next, online bioinformatics analysis and luciferase reporter were used to predict and validate the targeting relationship of miR-185-5p and RAB35. Finally, tumor cell-derived exosomes with genetic downregulation of RAB35 or overexpression of miR-185-5p were co cultured with their parental cells to verify the regulatory role of RAB35 on exosome secretion and function.

Results: In NSCLC tissues and cell lines, miR-185-5p was downregulated, while RAB35 was significantly upregulated. Overexpression of miR-185-5p or knockdown of RAB35 expression inhibited cell proliferation, migration and invasion. Furthermore, we elucidated that RAB35 is a direct target of miR-185-5p. Additionally, exosomes derived from tumor cells restored cell proliferation, migration and invasion, whereas exosomes secreted by tumor cells with downregulation of RAB35 expression or overexpression of miR-185-5p lost their ability to restore cell proliferation, migration and invasion.

Conclusions: Our results demonstrate that miR-185-5p inhibits tumor cell-derived exosomes-mediated proliferation, migration and invasion of NSCLC cells by downregulating RAB35 expression.

Long non-coding DANCR targets miR-185-5p to upregulate LIM and SH3 protein 1 promoting prostate cancer via the FAK/PI3K/AKT/GSK3β/snail pathway

BACKGROUND

Long non-coding RNA differentiation antagonizing non-protein coding RNA (DANCR) acts as an oncogene in different cancers, although its roles in prostate cancer are not fully reported. We aimed to explore its mechanism in facilitating the malignancy of prostate cancer.

METHODS

The expression of DANCR, microRNA (miR)-185-5p and LIM and SH3 protein 1 (LASP1) in 40 pairs of prostate cancer tissues and normal tissues, five prostate cancer cell lines and one epithelial cell line was assessed by a quantitative real-time polymerase chain reaction, western blotting and immunohistochemistry, respectively. In transfected PC3 and C4-2 cells, cell proliferation, migration, invasion, cell cycle distribution and epithelial-mesenchymal transition (EMT) protein expression were tested via cell counting kit-8, wound healing, transwell, flow cytometry and western blot assays, respectively. The interactions between DANCR, miR-185-5p and LASP1 were verified by a dual-luciferase reporter assay. Rescue experiments were conducted to determine the roles of DANCR on the malignant properties of PC3 and C4-2 cells. The involvement of the signaling pathway was examined using a p-FAK inhibitor.

RESULTS

DANCR and LASP1 expression was enhanced, whereas miR-185-5p expression was diminished in prostate cancer tissues and cell lines. Knockdown of DANCR suppressed cell proliferation, migration, invasion, G1-S transition and expression of EMT proteins of the transfected PC3 and C4-2 cells. DANCR sponged miR-185-5p to upregulate LASP1 expression. DANCR-miR-185-5p-LASP1 axis activates the FAK/PI3K/AKT/GSK3β/Snail pathway to promote the malignant properties of PC3 and C4-2 cells.

CONCLUSIONS

These findings suggest that DANCR exerts oncogenic roles in prostate cancer via the miR-185-5p/LASP1 axis activating the FAK/PI3K/AKT/GSK3β/Snail pathway. It can be a potential biomarker in the diagnosis and monitoring of prostate cancer.