MicroRNA-142-3p, a new regulator of RAC1, suppresses the migration and invasion of hepatocellular carcinoma cells

RAC1 regulates a diverse array of cellular events including migration and invasion. MicroRNAs (miRNAs) have a key role in the regulation of gene expression. In this study, we demonstrated that microRNA-142-3p (miR-142-3p) acted as a negative regulator of human RAC1. Overexpression of miR-142-3p decreased RAC1 mRNA and protein levels. Moreover, the overexpression of miR-142-3p suppressed, while blocking of miR-142-3p increased colony formation, migration and invasion in hepatocellular carcinoma (HCC) cell lines (QGY-7703 and SMMC-7721). RAC1 overexpression without the 3'untranslated region abolished the effect of miR-142-3p in the QGY-7703 and SMMC-7721 cells. These results demonstrated that miR-142-3p directly and negatively regulates RAC1 in HCC cells, which highlights the importance of miRNAs in tumorigenesis.     

Upregulation of miR-142-3p Improves Drug Sensitivity of Acute Myelogenous Leukemia through Reducing P-Glycoprotein and Repressing Autophagy by Targeting HMGB1

miR-142-3p was reported to be downregulated in acute myelogenous leukemia (AML) and acted as a novel diagnostic marker. However, the regulatory effect of miR-142-3p on drug resistance of AML cells and its underlying mechanism have not been elucidated. Here, we found that miR-142-3p was significantly downregulated and high mobility group box 1 (HMGB1) was dramatically upregulated in AML samples and cells, as well as drug-resistant AML cells. P-gp level and autophagy were markedly enhanced in HL-60/ADR and HL-60/ATRA cells. miR-142-3p overexpression improved drug sensitivity of AML cells by inhibiting cell viability and promoting apoptosis, and inhibited P-gp level and autophagy in drug-resistant AML cells, whereas HMGB1 overexpression obviously reversed these effect. HMGB1 was demonstrated to be a target of miR-142-3p, and miR-142-3p negatively regulated HMGB1 expression. In conclusion, our study elucidated that upregulation of miR-142-3p improves drug sensitivity of AML through reducing P-glycoprotein and repressing autophagy by targeting HMGB1, contributing to better understanding the molecular mechanism of drug resistance in AML.     

Decreased Expression of miR-21, miR-26a,miR-29a,and miR-142-3p in CD4+ T Cells and Peripheral Blood from Tuberculosis Patients

The vast majority of Mycobacterium tuberculosis (M. tuberculosis) infected individuals are protected from developing tuberculosis and T cells are centrally involved in this process. MicroRNAs (miRNA) regulate T-cell functions and are biomarker candidates of disease susceptibility and treatment efficacy in M. tuberculosis infection. We determined the expression profile of 29 selected miRNAs in CD4⁺ T cells from tuberculosis patients and contacts with latent M. tuberculosis infection (LTBI). These analyses showed lower expression of miR-21, miR-26a, miR-29a, and miR-142-3p in CD4⁺ T cells from tuberculosis patients. Whole blood miRNA candidate analyses verified decreased expression of miR-26a, miR-29a, and miR-142-3p in children with tuberculosis as compared to healthy children with LTBI. Despite marked variances between individual donor samples, trends of increased miRNA candidate expression during treatment and recovery were observed. Functional in vitro analysis identified increased miR-21 and decreased miR-26a expression after re-stimulation of T cells. In vitro polarized Interleukin-17 positive T-cell clones showed activation-dependent miR-29a up-regulation. In order to characterize the role of miR-29a (a described suppressor of Interferon-γ in tuberculosis), we analyzed M. tuberculosis specific Interferon-γ expressing T cells in children with tuberculosis and healthy contacts but detected no correlation between miR-29a and Interferon-γ expression. Suppression of miR-29a in primary human T cells by antagomirs indicated no effect on Interferon-γ expression after in vitro activation. Finally, classification of miRNA targets revealed only a moderate overlap between the candidates. This may reflect differential roles of miR-21, miR-26a, miR-29a, and miR-142-3p in T-cell immunity against M. tuberculosis infection and disease.     

IL-1β promotes hypoxic vascular endothelial cell proliferation through the miR-24-3p/NKAP/NF-κB axis

Purpose: Our previous data indicated that miR-24-3p is involved in the regulation of vascular endothelial cell (EC) proliferation and migration/invasion. However, whether IL-1β affects hypoxic HUVECs by miR-24-3p is still unclear. Therefore, the present study aimed to investigate the role and underlying mechanism of interleukin 1β (IL-1β) in hypoxic HUVECs.Methods: We assessed the mRNA expression levels of miR-24-3p, hypoxia-inducible factor-1α (HIF1A) and NF-κB-activating protein (NKAP) by quantitative real-time polymerase chain reaction (RT-qPCR). ELISA measured the expression level of IL-1β. Cell counting kit-8 (CCK-8) assays evaluated the effect of miR-24-3p or si-NKAP+miR-24 on cell proliferation (with or without IL-1β). Transwell migration and invasion assays were used to examine the effects of miR-24-3p or si-NKAP+miR-24-3p on cell migration and invasion (with or without IL-1β). Luciferase reporter assays were used to identify the target of miR-24-3p.Results: We demonstrated that in acute myocardial infarction (AMI) patient blood samples, the expression of miR-24-3p is down-regulated, the expression of IL-1β or NKAP is up-regulated, and IL-1β or NKAP is negatively correlated with miR-24-3p. Furthermore, IL-1β promotes hypoxic HUVECs proliferation by down-regulating miR-24-3p. In addition, IL-1β also significantly promotes the migration and invasion of hypoxic HUVECs; overexpression of miR-24-3p can partially rescue hypoxic HUVECs migration and invasion. Furthermore, we discovered that NKAP is a novel target of miR-24-3p in hypoxic HUVECs. Moreover, both the overexpression of miR-24-3p and the suppression of NKAP can inhibit the NF-κB/pro-IL-1β signaling pathway. However, IL-1β mediates suppression of miR-24-3p activity, leading to activation of the NKAP/NF-κB pathway. In conclusion, our results reveal a new function of IL-1β in suppressing miR-24-3p up-regulation of the NKAP/NF-κB pathway.     

miR-142-3p is a tumor suppressor that inhibits estrogen receptor expression in ER-positive breast cancer

Estrogen receptors (ERs) are involved in the development of many types of malignant tumors, in particular, breast cancer. Among others, ERs affect cell growth, proliferation, and differentiation. The microRNA (miRNA) miR-142-3p has been shown to inhibit carcinogenesis by regulating various cellular processes, including cell cycle progression, cell migration, apoptosis, and invasion. It does so via targeting molecules involved in a range of signaling pathways. We surgically collected 20 ER-positive breast cancer samples, each with matched adjacent normal breast tissue, and measured the expression of miR-142-3p via quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatics methods, luciferase reporter assay, qRT-PCR, and western blot analysis were used to assess whether miR-142-3p could target ESR1, which encodes the estrogen receptor, in ER-positive breast cancer cells and patient samples. We also restored miRNA expression and performed cell viability, cytotoxicity, and colony formation assays. Western blot analysis and qRT-PCR were used to study the expression of apoptosis and stemness markers. We found that miR-142-3p is downregulated in ER-positive breast cancers. Restoration of miR-142-3p expression in ER-positive breast cancer cells reduced cell viability, induced apoptosis via the intrinsic pathway and decreased both colony formation and the expression of stem cell markers. Bioinformatic analysis predicted miR-142-3p could bind to 3′-untranslated region ESR1 messenger RNA (mRNA). Consistently, we demonstrated that miR-142-3p reduced luciferase activity in ER-positive breast cancer cells, and decreased ESR1 expression in both mRNA and protein levels. The results revealed miR-142-3p and ESR1 expression correlated negatively in ER-positive breast cancer samples. The results suggest miR-142-3p acts as a tumor suppressor via multiple mechanisms. Thus, restoration of miR-142-3p expression, for example, via miRNA replacement therapy, may represent an effective strategy for the treatment of ER-positive breast cancer patients.     

miR-342-3p suppresses proliferation,migration and invasion by targeting FOXM1 in human cervical cancer

FOXM1 is a well-established oncogenic factor that has been reported to be involved in multiple biological processes including cell proliferation, growth, angiogenesis, migration and invasion. It can also be regulated by miRNAs. In this study, we reported that FOXM1 is directly targeted by miR-342-3p, which is down-regulated along with its host gene, EVL, in human cervical cancer tissues compared to the adjacent normal tissues. Functional studies suggested that the overexpression of miR-342-3p inhibits cell proliferation, migration and invasion in cervical cell lines. FOXM1 is upregulated and negatively correlates with miR-342-3p in cervical cancer tissues, and the overexpression of FOXM1 rescues the phenotype changes induced by the overexpression of miR-342-3p.     

miR-142-3p/5p role in cancer: From epigenetic regulation to immunomodulation

MicroRNAs (miRNAs) play critical roles in cancer pathobiology, acting as regulators of gene expression and pivotal drivers of tumorigenesis. It is believed that miRNAs act through canonical mechanisms, involving the binding of mature miRNAs to target messenger RNAs (mRNAs) and subsequent repression of protein translation or degradation of target mRNAs. miR-142-3p/5p has been extensively studied and established as a key regulator in various malignancies. Recent discoveries have revealed miR-142-3p/5p serve as either oncogene or tumor suppressor in cancer. By targeting epigenetic factor and cancer-related signaling pathway, miR-142-3p/5p can regulate wide range of downstream genes. The immune modulatory role of miR-142-3p/5p has been shown in various cancers, which provides significant insight into immunosuppression and tumor escape from the immune response. Exosomes with miR-142-3p/5p facilitate cell communication and can affect cancer cell behavior, offering potential therapeutic, and diagnosis applications in cancer therapy. In this review, for the first time, we comprehensively summarize the current knowledge regarding mentioned functions of miR-142-3p/5p in cancer pathobiology.     

miR-103a-2-5p/miR-30c-1-3p inhibits the progression of prostate cancer resistance to androgen ablation therapy via targeting androgen receptor variant 7

Androgens and androgen receptors are vital factors involved in prostate cancer progression, and androgen ablation therapies are commonly used to treat advanced prostate cancer. However, the acquisition of androgen ablation therapy resistance remains a challenge. Recently, androgen receptor splicing variants lacking the ligand-binding domain have been reported to play a critical role in the acquisition of androgen ablation therapy resistance. In the present study, we revealed that the messenger RNA expression and the protein levels of an androgen receptor variant 7 (AR-V7) were higher in prostate cancer tissue samples and in the AR-positive prostate cancer cell line, VCaP. In contrast, microRNA (miR)-30c-1-3p/miR-103a-2-5p expression was significantly downregulated in tumor tissues and cells. miR-30c-1-3p/miR-103a-2-5p overexpression could inhibit AR-V7 expression, suppress VCaP cell growth, and inhibit AR-V7 downstream factor expression by directly targeting the 3′-untranslated region of AR-V7. Under enzalutamide (Enza) treatment, the effects of AR-V7 overexpression were the opposite of those of miR-103a-2-5p/miR-30c-1-3p overexpression; more importantly, the effects of miR-103a-2-5p/miR-30c-1-3p overexpression could be significantly reversed by AR-V7 overexpression under Enza. In summary, we demonstrated a novel mechanism of the miR-30c-1-3p/miR-103a-2-5p/AR-V7 axis modulating the cell proliferation of AR-positive prostate cancer cells via AR downstream targets. The clinical application of miR-30c-1-3p/miR-103a-2-5p needs further in vivo validation.     

Conjugated linoleic acid supplementation caused reduction of perilipin1 and aberrant lipolysis in epididymal adipose tissue

MicroRNAs (miRNAs) have emerged as powerful regulators of multiple processes linked to human cancer, including cell apoptosis, proliferation and migration, suggesting that the regulation of miRNA function could play a critical role in cancer progression. Recent studies have found that human serum/plasma contains stably expressed miRNAs. If they prove indicative of disease states, miRNAs measured from peripheral blood samples may be a source for routine clinical detection of cancer. Our studies showed that both miR-508-3p and miR-509-3p were down-regulated in renal cancer tissues. The level of miR-508-3p but not miR-509-3p in renal cell carcinoma (RCC) patient plasma demonstrated significant differences from that in control plasma. In addition, the overexpression of miR-508-3p and miR-509-3p suppressed the proliferation of RCC cells (786-0), induced cell apoptosis and inhibited cell migration in vitro. Our data demonstrated that miR-508-3p and miR-509-3p played an important role as tumor suppressor genes during tumor formation and that they may serve as novel diagnostic markers for RCC.     

Inhibition of RAC1-GEF DOCK3 by miR-512-3p contributes to suppression of metastasis in non-small cell lung cancer

MicroRNAs are a class of small non-coding RNAs regulating gene expression. In this study, we demonstrated that retinoic acid (RA) treatment increases the expression of miR-512-3p. Overexpression of miR-512-3p inhibited cell adhesion, migration, and invasion in non-small cell lung cancer (NSCLC) cell lines A549 and H1299. miR-512-3p inhibitor partially reversed these effects in H1299 cells stably expressing miR-512. We identified DOCK3, a RAC1-GEF (guanine nucleotide exchange factor), as a target gene of miR-512-3p. Overexpression of miR-512-3p led to the decrease of DOCK3 protein but not its mRNA. Knockdown of DOCK3 resulted in similar effects on adhesion, migration, and invasion as observed of miR-512-3p overexpression. Active RAC1 pull-down assay indicated that overexpression of miR-512-3p could decrease the activity of RAC1 with a higher efficiency than that of DOCK3 knockdown. Furthermore, expression of miR-512-3p was suppressed in most NSCLC patient tumor samples compared to its paired normal controls, suggesting that miR-512-3p might play a crucial role in lung cancer development. In conclusion, our results supported that miR-512-3p could inhibit tumor cell adhesion, migration, and invasion by regulating the RAC1 activity via DOCK3 in NSCLC A549 and H1299 cell lines.     

miR-340通过靶向GRP78促进结直肠癌细胞凋亡并抑制其增殖、迁移和侵袭

miR-340能够促进癌细胞的增殖和侵袭,但是在结直肠癌中miR-340如何调控癌症的发生与发展鲜有报道.本研究探究miR-340在结直肠癌细胞中的生物学功能和靶基因调控机制.首先通过RT-qPCR检测不同的结直肠癌细胞株中miR-340的表达水平,再利用过表达和抑制miR-340,分别转染COLO-205细胞,以CC...     

miR-219-5p targets TBXT and inhibits breast cancer cell EMT and cell migration and invasion

miR-219-5p has been reported to act as either a tumor suppressor or a tumor promoter in different cancers by targeting different genes. In the present study, we demonstrated that miR-219-5p negatively regulated the expression of TBXT, a known epithelial–mesenchymal transition (EMT) inducer, by directly binding to TBXT 3′-untranslated region. As a result of its inhibition on TBXT expression, miR-219-5p suppressed EMT and cell migration and invasion in breast cancer cells. The re-introduction of TBXT in miR-219-5p overexpressing cells decreased the inhibitory effects of miR-219 on EMT and cell migration and invasion. Moreover, miR-219-5p decreased breast cancer stem cell (CSC) marker genes expression and reduced the mammosphere forming capability of cells. Overall, our study highlighted that TBXT is a novel target of miR-219-5p. By suppressing TBXT, miR-219-5p plays an important role in EMT and cell migration and invasion of breast cancer cells.     

LncRNA-UCA1 modulates progression of colon cancer through regulating the miR-28-5p/HOXB3 axis

Emerging evidence has shown that the long noncoding RNA urothelial carcinoma–associated 1 (UCA1) plays a tumor-promoting role in colorectal cancer, while miR-28-5p shows tumor-inhibitory activity in several tumor types. However, the mechanisms both of these in colon cancer progression are still unknown. In this work, the detailed roles and mechanisms of UCA1 and its target genes in colon cancer were studied. The results showed that UCA1 was upregulated in colon cancer tissues when compared with the adjacent nonhumorous tissues, as well as in the various colon cancer cell lines, but the expression of miR-28-5p showed an opposite trend. Furthermore, a high UCA1 level in colon cancer tissues is positively associated with the tumor size and advanced tumor stages. Functional assays revealed that both UCA1 knockdown and miR-28-5p overexpression could inhibit colon cancer cell growth and migration. Further mechanistic studies indicated that UCA1 knockdown played tumor suppressive roles in SW480 and HT116 cells through binding with miR-28-5p. We also, for the first time, identified HOXB3 as the target gene of miR-28-5p and that HOXB3 overexpression could mediate the functions of UCA1 in cell proliferation and migration of colon cancer cells. In conclusion, our data provided evidence for the regulatory network of UCA1/miR-28-5p/HOXB3 in colon cancer, suggesting that UCA1, miR-28-5p, and HOXB3 are the potential targets for colon cancer therapy.     

miR-214-5p targets KLF5 and suppresses proliferation of human hepatocellular carcinoma cells

MicroRNAs (miRNAs) are small endogenous conserved RNAs regulating genes expression through base pairing with the 3′-untranslated region (3′-UTR) of target messenger RNAs. MiR-214-5p is a newly identified miRNA with its biological role largely unknown. In this study, we explored miR-214-5p expression status in 78 paired tumor and nontumor tissues obtained from patients with hepatocellular carcinoma (HCC) by RT-qPCR. The effects of miR-214-5p expression on HCC cell proliferation, cell cycle progression, and cell migration were measured by CCK-8 assay, flow cytometry, and wound-healing assay. A dual-luciferase activity assay was performed to identify whether KLF5 was a target of miR-214-5p. Kaplan-Meier curve and log-rank test were used to investigate the effects of miR-214-5p and KLF5 on overall survival and disease-free survival of patients with HCC. We found miR-214-5p expression was sharply reduced in HCC tissues and cell lines compared with the normal tissues and cell lines. Functional assay revealed that miR-214-5p overexpression could downregulate cell proliferation, cell migration, and arrested cell cycle at G0/G1 phase. Further, we validated Krüppel-like factor 5 (KLF5) as a direct target of miR-214-5p, and was upregulated in HCC and inversely correlated with the expression of miR-214-5p. Moreover, we found the low expression of miR-214-5p and high expression of KLF5 were correlated with tumor size, tumor stage, and poorer 5-year overall survival and disease-free survival of patients with HCC. In conclusion, our results suggested miR-214-5p functions as a tumor suppressor through targeting KLF5 in HCC. Also, miR-214-5p and KLF5 were identified as potential prognostic markers and might be therapeutic targets in HCC.     

SNHG12 promotes carcinogenesis of human renal cell cancer via functioning as a competing endogenous RNA and sponging miR-30a-3p

Small nucleolar RNA host gene 12 (SNHG12) has been indicated in the tumorigenesis of various human cancers, including clear cell renal cell carcinoma (ccRCC). However, the underlying mechanisms of SNHG12 driving progression of ccRCC remain incompletely understood. In the present study, we discovered that SNHG12 is up-regulated in ccRCC and that overexpression of SNHG12 predicted poor clinical outcome of ccRCC patients. SNHG12 knockdown notably inhibited proliferation and migration of RCC cells. Furthermore, we discovered that miR-30a-3p, a putative ccRCC inhibitor, was competitively sponged by SNHG12. Via the crosstalk network, SNHG12 was capable of up-regulating multiple target genes of miR-30a-3p, namely, RUNX2, WNT2 and IGF-1R, which have been identified to facilitate tumorigenesis of ccRCC. Taken together, our present study suggested a novel ceRNA network, in which SNHG12 could promote the malignancy of ccRCC although competitively binding with miR-30a-3p and consequently release the expression of its downstream cancer-related genes.