MicroRNAs: biogenesis, roles for carcinogenesis and as potential biomarkers for cancer diagnosis and prognosis

The current status of miRNA in urinary bladder cancer: A minireview and strength, weakness, opportunity, and threat analysis

MicroRNAs, small noncoding RNA molecules, are critical in modulating gene expression and contribute substantially to the initiation and progression of urinary bladder cancer (UBCa), a major malignancy affecting people globally. UBCa is known for its high recurrence rates and significant heterogeneity. The stability of miRNAs in body fluids such as urine and blood are excellent potential noninvasive markers for early detection, monitoring treatment progress, and predicting outcomes of patients with UBCa. In addition, miRNAs could also improve the effectiveness of immunotherapy and support the development of personalized treatment strategies. Despite their significant potential, challenges such as variability in the expression of miRNAs and shortcomings in their delivery systems must be carefully addressed. This strength, weakness, opportunity, and threat (SWOT) analysis highlights the crucial role of miRNAs in UBCa and explores their potential in advancing precision oncology.

Functional role of lncRNAs in gastrointestinal malignancies: the peculiar case of small nucleolar RNA host gene family

Long noncoding RNAs (lncRNAs) play crucial roles in normal physiology and are often de-regulated in disease states such as cancer. Recently, a class of lncRNAs referred to as the small nucleolar RNA host gene (SNHG) family have emerged as important players in tumourigenesis. Here, we discuss new findings describing the role of SNHGs in gastrointestinal tumours and summarize the three main functions by which these lncRNAs promote carcinogenesis, namely: competing with endogenous RNAs, modulating protein function, and regulating epigenetic marking. Furthermore, we discuss how SNHGs participate in different hallmarks of cancer, and how this class of lncRNAs may serve as potential biomarkers in cancer diagnosis and therapy.

MicroRNA-409-5p inhibits cell proliferation, and induces G2/M phase arrest and apoptosis by targeting DLGAP5 in ovarian cancer cells

MicroRNA (miRNA/miR)-409-5p has been reported to be implicated in prostate and breast cancers; however, its functional role in ovarian cancer (OC) remains unclear. Therefore the aim of the present study was to investigate the clinical significance and biological function of miR-409-5p in OC. Here, reverse transcription-quantitative PCR analysis was performed to detect miR-409-5p expression in OC tissues and cell lines. The association between miR-409-5p expression and the clinicopathological characteristics of patients with OC was assessed using the Fisher's exact test. Furthermore, the Cell Counting Kit-8 assay was performed to assess cell proliferation. Cell cycle distribution and apoptosis were evaluated via flow cytometric analysis, and the target gene of miR-409-5p was validated via the dual-luciferase reporter assay. The results demonstrated that miR-409-5p expression was significantly downregulated in OC tissues and cell lines compared with adjacent normal tissues and epithelial cells, respectively. In addition, low miR-409-5p expression was significantly associated with tumor size (P=0.044) and the International Federation of Gynecology and Obstetrics staging system (P=0.005). Notably, overexpression of miR-409-5p suppressed cell proliferation, and induced G₂/M phase arrest and apoptosis of OC cells. Mechanistically, discs large-associated protein 5 (DLGAP5) was identified as a novel target of miR-409-5p, which was negatively regulated by miR-409-5p. DLGAP5 expression was significantly upregulated in OC tissues and cell lines compared with adjacent normal tissues and epithelial cells, respectively. Furthermore, overexpression of DLGAP5 reversed the effects of miR-409-5p on SKOV-3 cell proliferation, and G₂/M phase and apoptosis. Taken together, these results suggest that miR-409-5p acts as a tumor suppressor in OC by modulating DLGAP5 expression.

Serum Expression Levels of Certain miRNAs in Predicting Diagnosis, Prognosis, and Response to Chemotherapy in Malignant Pleural Mesothelioma

Background:

miRNAs are involved in tumor pathogenesis and can therefore be determined in the primary tumor, plasma and serum, and body fluids. As in various cancers, their role in the diagnosis, prognosis, and treatment of patients with malignant pleural mesothelioma (MPM) may be important.

Aims:

To analyze the predictive value of miR-16-5p, miR-29c-3p, miR-31-5p, miR-125a-5p, miR-320a, miR-484 and miR-532-5p expressions for diagnosis, prognosis and response to treatment in patients with MPM.

Study Design:

Prospective case-control study.

Methods:

In the first phase of the study, blood samples were collected from 101 MPM patients before chemotherapy and from 24 healthy donors (HDs). In the second phase, the blood samples were collected from 74 MPM patients who had received chemotherapy when the best overall response and disease recurrence were determined. A quantitative real-time polymerase chain reaction was undertaken to detect the miRNA expression levels. The miRNA expression profiles of MPM patients were compared with those of HDs. The associations between the expression levels of miRNAs and prognosis and response to treatment were then evaluated.

Results:

All miRNAs, except miR-31-5p, were expressed differently in MPM relative to that in HDs. The expression level of miR-16-5p decreased when compared with that of HDs, and the expression levels of miR-29c-3p, miR-125a-5p, miR-320a, miR-484, and miR-532-5p increased when compared with that of HDs. The sensitivity and specificity values of miR-29c-3p, miR-125a-5p, miR-320a, miR-484, and miR-532-5p for discriminating MPM from HDs were 85.9% and 59.1%, 95.1% and 62.5%, 87.1% and 79.2%, 82.2% and 58.3%, and 69.3% and 82.6%, respectively. After adjusting for the histological subtype, stage, and treatment, the miR-29c-3p, miR-125a-5p, and miR-484 were associated with longer survival. The miRNA expression levels did not change longitudinally for the determination of chemotherapy response and recurrence.

Conclusion:

miRNAs may be useful in diagnosing patients with MPM and provides helpful information in determining the prognosis of patients.

The role of miR-370 and miR-138 in the regulation of BMP2 suppressor gene expression in colorectal cancer: preliminary studies

PURPOSE

Colorectal cancer (CRC) is the fourth-most common cancer worldwide and the second most common cancer cause of death in the world. The components of the TGFβ-signalling pathway, which are often affected by miRNAs, are involved in the regulation of apoptosis and cell cycle. Therefore, in the current study, the expression of BMP2 gene in CRC tissues at different clinical stages compared to the non-tumour tissues has been assessed. Moreover, the plasma BMP2 protein concentration in the same group of CRC patients has been validated. Due to the constant necessity to conduct further research of the correlation between specific miRNAs and mRNAs in CRC, in silico analysis has been performed to select miRNAs that regulate BMP2 mRNA.

METHODS

The cDNA samples from tumor and non-tumor tissue were used in a qPCR reaction to determine the mRNA expression of the BMP2 gene and the expression of selected miRNAs. The concentration of BMP2 protein in plasma samples was also measured.

RESULTS

It was indicated that BMP2 was downregulated in CRC tissue. Moreover, miR-370 and miR-138 expression showed an upward trend. Decreased BMP2 with accompanied increasing miR-370 and miR-138 expression was relevant to the malignant clinicopathological features of CRC and consequently poor patient prognosis.

CONCLUSION

Our data suggest that miR-370 with its clear expression in plasma samples may be a potential diagnostic marker to determine the severity of the disease in patients at a later stage of colorectal cancer.

microRNAs in human brucellosis: A promising therapeutic approach and biomarker for diagnosis and treatment

INTRODUCTION

Human brucellosis is a zoonotic bacterial disease with up to 500,000 new cases each year. The major evasion mechanisms from the host immune system by Brucella are restraint of complement pathway and Toll-like receptors signaling pathways, interference with efficient antigen presentation to CD4-positive T lymphocytes, selective subversion of autophagy pathways, inhibition of dendritic cell stimulation, inhibition of autophagolysosomal fusion, and macrophage apoptosis. Many molecular and cellular pathways contribute to brucellosis that microRNAs have a vital function in the immunopathogenesis of this disease. In this regard, these molecules apply for their roles by modulating various events like inflammatory reactions and immune defense. Recently, in the case of immunity to human brucellosis, it has been shown that microRNAs play an important role in immunity against these bacteria.

METHODS AND RESULTS

In this study, we tried to review the immune defense and immunopathogenesis of Brucella infection and highlight the current knowledge of the microRNAs in infected cells by Brucella pathogens. The recent findings suggest that the regulation of microRNAs expression is impaired during brucellosis infection, which may contribute to disease progression or inhibition by modulating immune responses against this pathogen.

CONCLUSIONS

The interplay between miRNAs and Brucella pathogens and the underlying process required comprehensive examination to unravel the novel therapeutic or diagnostic approaches.

MicroRNA-708 targeting ZNF549 regulates colon adenocarcinoma development through PI3K/AKt pathway

Colon adenocarcinoma (COAD) is the most common type of gastrointestinal cancer and is still the third leading cause of cancer-related mortality worldwide. Therefore, finding new and promising drugs to eradicate cancer may be a feasible method to treat COAD patients. Cys2-His2 zinc finger proteins (ZFPs) is one of the largest transcription factor family and many of them are highly involved in regulation of cell differentiation, proliferation, apoptosis, and neoplastic transformation. In this study, we identified a tumor-inhibiting factor, ZNF549, which expressed lowly in COAD tissues and COAD cell lines (HT29, HCT116, SW480, LoVo, and SW620). Overexpression of ZNF549 inhibit the ability of COAD cell proliferation and migration. On the contrary, decreasing the ZNF549 expression level promote the ability of COAD cell proliferation and migration. Through bioinformatics analysis, we found that ZNF549 was a potential target of hsa-miR-708-5p (miR-708-5p). Furthermore, we verified the possibility of miR-708-5p targeting the ZNF549 gene, and miR-708-5p inhibited the expression of ZNF549 by luciferase reporter assays, qRT-PCR and western blot assays. Moreover, the relationship between miR-708-5p and phosphatidylinositol 3-kinase/AKt (PI3K/AKt) signal pathway was elucidated. Overexpression and inhibition of miR-708-5p resulted in increased and decreased expression of p-AKt and p-PI3K in HCT116 cells, respectively. RT-qPCR and western blot assays results demonstrated that miR-708-5p regulated COAD cells development by promoting the process of Epithelial-mesenchymal transition (EMT) through PI3K/AKt signaling pathway. In summary, our findings demonstrated that ZNF549, the target gene of miR-708-5p, functions as a tumor suppressor to inhibit COAD cell lines proliferation and migration through regulate the PI3K/AKt signal pathway.

Long non‑coding RNA ZEB2‑AS1 affects cell proliferation and apoptosis via the miR‑122‑5p/PLK1 axis in acute myeloid leukemia

Acute myeloid leukemia (AML) is a highly heterogeneous disease featured by the clonal accumulation of immature myeloid cells. Zinc finger E‑box binding homeobox 2 (ZEB2)‑antisense RNA 1 (AS1) has been verified to participate in the progression of several types of cancer, including AML. However, the potential mechanisms of ZEB2‑AS1 in AML have not yet been fully elucidated. The present study aimed to elucidate the role and regulatory mechanisms of ZEB2‑AS1 in AML. The expression of ZEB2‑AS1, microRNA‑122‑5p (miRNA/miR‑122‑5p) and polo‑like kinase 1 (PLK1) was detected by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) in AML tissues or cells. Cell proliferation and apoptosis were examined by methyl thiazolyl tetrazolium (MTT) assay and apoptosis assay, respectively. The protein levels were examined by western blot analysis. The targeted sequence between miR‑122‑5p and ZEB2‑AS1 or PLK1 was predicted using an online database and verified by dual‑luciferase reporter assay. A mouse tumor xenograft model was established to confirm the effects of ZEB2‑AS1 on tumor growth in vivo. The results revealed that the expression levels of ZEB2‑AS1 and PLK1 were upregulated, while those of miR‑122‑5p were downregulated in AML tissues and cells. The knockdown of ZEB2‑AS1 inhibited proliferation and induced apoptosis in vitro, and inhibited tumor growth in vivo. By experimental verification, ZEB2‑AS1 was found to negatively regulate miR‑122‑5p expression and PLK1 was found to be a target gene of miR‑122‑5p. Furthermore, ZEB2‑AS1 was verified to regulate the expression of PLK1 by sponging miR‑122‑5p in AML cells. On the whole, the findings of the present study demonstrate that ZEB2‑AS1 promotes cell proliferation and inhibits apoptosis, at least partly by targeting PLK1 mediated by miR‑122‑5p in AML cells.

Role of microRNAs in Staphylococcus aureus infection: Potential biomarkers and mechanism

Staphylococcus aureus is known as a common pathogen that colonizes 30% of healthy humans. Additionally, this bacterium can cause a number of serious infections, that is, endocarditis, bacteremia, pneumonia, wound, skin infections, and tissue abscesses. A variety of cellular and molecular pathways and targets are involved in response against S. aureus. Among them, microRNAs (miRNAs) have crucial roles in response against S. aureus. In this regard, it has been shown that these molecules exert their regulatory roles via modulating a wide range of events, such as inflammatory reactions, host innate, and adaptive immunity. Current works have provided insight into the crucial involvement of miRNAs in immune defense toward Staphylococcal infections. Herein, we highlighted the current findings on the deregulation of different miRNAs in S. aureus-infected cells. Moreover, we summarized the mechanisms and targets of miRNAs in S. aureus infections.

MicroRNAs: Biogenesis, Functions and Potential Biomarkers for Early Screening, Prognosis and Therapeutic Molecular Monitoring of Nasopharyngeal Carcinoma

According to reports published, the aberrant expression of microRNAs (miRNAs), a class of 19–25 nucleotide-long small non-coding RNAs, is responsible for human cancers, including nasopharyngeal cancer (NPC). The dysregulation of miRNAs that act either as a tumor suppressor or oncogene, leading to a wide range of NPC pathogenesis pathways, includes the proliferation, invasion, migration as well as the metastasis of NPC cells. This article reviews and highlights recent advances in the studies of miRNAs in NPC, with a specific demonstration of the functions of miRNA, especially circulating miRNAs, in the pathway of NPC pathogenesis. Additionally, the possible use of miRNAs as early screening and prognostic biomarkers and for therapeutic molecular monitoring has been extensively studied.

MiR-30e-5p inhibits the migration and invasion of nasopharyngeal carcinoma via regulating the expression of MTA1

The study explored the effect of miR-30e-5p on nasopharyngeal carcinoma (NPC). MiR-30e-5p levels in NPC cancer and adjacent normal samples, in metastatic and non-metastatic cancer samples of NPC, and in NP69 cell and five NPC cell lines were determined by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between miR-30e-5p and MTA1 was confirmed by dual-luciferase reporter assay, Western blot and qRT-PCR. The viability, migration and invasion of 5-8F and 6-10B cells were determined by CCK-8, scratch test and transwell assays, respectively. The levels of migration-related proteins (vimentin and Snail) and invasion-related proteins (MMP2 and MMP3) in NPC cells were detected by Western blot. The results showed that low expression of miR-30e-5p was associated with HNSC cancer, NPC, metastasis of NPC and NPC cell lines. Overexpressed miR-30e-5p in HNSC cancer and NPC was predictive of a better prognosis of patients. In addition, the viability, migration and invasion were reduced by up-regulating miR-30e-5p in 5-8F cells, but promoted by down-regulated miR-30e-5p in 6-10B cells. MiR-30e-5p reversed the migration and invasion of NPC cells regulated by MTA1, and inhibited migration and invasion of NPC cells via regulating MTA1 expression.

miR-15b enhances the proliferation and migration of lung adenocarcinoma by targeting BCL2

Background

Lung adenocarcinoma (LUAD) is a subtype of lung cancer (LC), which is the most common tumor worldwide. Accumulating evidence has elucidated an important role of microRNAs (miRNAs) in mediating the development and progression of several tumors. The purpose of this study was to explore the role and underlying mechanism of miR‐15b in LUAD.

Methods

CCK‐8 and Transwell assays were conducted to measure the capacities of cell viability and migration in SPC‐A1 cells. Luciferase assay was utilized to verifymiR‐15b direct binding to BCL2 mRNA 3′‐UTR.

Results

We determined that miR‐15b was overexpressed in LUAD and miR‐15b overexpression predicted a significantly worse outcome in patients with LUAD. miR‐15b improved LUAD growth in vitro and vivo. miR‐15b enhanced cell migration and epithelial–mesenchymal transition (EMT) in LUAD. miR‐15b promoted cell viability, migration and EMT through inhibiting BCL2 expression by targeting to its mRNA 3′‐UTR. BCL2 reversed functions of miR‐15b on promoting cell proliferation, migration and EMT in SPC‐A1 cells.

Conclusions

miR‐15b promoted cell viability, migration and EMT by targeting BCL2 in LUAD. The newly identified miR‐15b/BCL2 axis provides a novel insight into the pathogenesis of LUAD.

Assessment of Expression of Homeobox A5 in Endometrial Cancer on the mRNA and Protein Level

BACKGROUND

Endometrial cancer is one of the most common gynecological cancer in the developed countries and occurs mainly in postmenopausal women. Angiogenesis is important for cancer formation as it provides nutrients for growing tumor mass. Most tumors do not show detectable Homeobox A5 (HOXA5 level), suggesting its potential role as a cancer suppressor. It was demonstrated that HOXA5 is involved in the progression of various types of cancer and the loss of its expression correlates with higher pathological grade and poorer outcome.

OBJECTIVE

The aim of the study was to evaluate HOXA5 expression at transcriptome and protein levels.

MATERIALS AND METHODS

The study enrolled 45 women diagnosed with endometrial cancer and 15 without neoplastic changes. The histopathological examination allowed us to divide cancer tissue samples according to the degree of histological differentiation: G1, 17; G2, 15; G3, 13. The expression of the HOXA5 protein was determined by immunohistochemistry. Microarray and RT-qPCR techniques were used to assess HOXA5 expression at the mRNA level.

RESULTS

The reaction to the HOXA5 protein was only visible in glandular cells in G1 endometrial cancer and was lower compared to the control. In grades 2 and 3, reactions were noted at the limit of the method's sensitivity. In addition, reduced HOXA5 expression was observed at the transcriptome level.

CONCLUSION

HOXA5 may become a potential complementary molecular marker, allowing early detection of neoplastic changes in the endometrium. It also seems that detection of HOXA5 at the mRNA and protein levels may be helpful in improving the accuracy of diagnosis and planning effective oncological therapy.

miR-663b promotes colorectal cancer progression by activating Ras/Raf signaling through downregulation of TNK1

MiR-663b has been demonstrated to be abnormally expressed in several cancer types and was involved in the progression of cancer. Although overexpression of miR-663b in colorectal cancer was observed, the role of miR-663b in colorectal cancer cells has not been identified yet. In this study, we analyzed expression of miR-663b in colorectal tumors and explored the molecular mechanism of miR-663b in colorectal cancer cells. MiR-663b was significantly overexpressed in colorectal tumors and cell lines. Downregulation of miR-663b inhibited cell proliferation and sphere forming ability in colorectal cancer cells. In addition, miR-663b downregulation inactivated Ras/Raf signaling activity and subsequently decreased YAP1 and CD44 expression in colorectal cancer cells. Using TargetScan software, TNK1, a negative regulator of Ras/Raf signaling, was predicted to be a target gene of miR-663b. Western blotting and RT-qPCR showed that TNK1 expression was negatively regulated by miR-663b. In addition, the direct binding of miR-663b to TNK1 mRNA was proved by dual luciferase reporter assay. Furthermore, downregulation of miR-663b inhibited colorectal cancer cell proliferation and stemness, which was reversed after siRNA-mediated silencing of TNK1. In conclusion, the current study revealed a pivotal role of miR-663b in the progression of colorectal cancer.

LINC00958 Promotes The Malignancy Of Nasopharyngeal Carcinoma By Sponging microRNA-625 And Thus Upregulating NUAK1

Purpose

The aberrant expression of long noncoding RNAs (lncRNAs) indicates progression of various diseases. LINC00958 has been well studied in several types of human cancer; however, the expression profile, functions, and potential mechanism of action of this lncRNA in nasopharyngeal carcinoma (NPC) remain largely unclear and still need to be elucidated. In the present study, we aimed to measure LINC00958 expression in NPC, determine its clinical value, and explore its roles in NPC progression as well as the mechanisms behind these processes.

Methods

The expression profile of LINC00958 in NPC was evaluated by reverse-transcription quantitative polymerase chain reaction (RT-qPCR). A series of functional assays, including the Cell Counting Kit-8 assay, flow cytometry, a Transwell assay, and an in vivo nude mouse model, were utilized to determine the participation of LINC00958 in the malignancy of NPC.

Results

LINC00958 was found to be upregulated in NPC tissue specimens and cell lines. The LINC00958 overexpression significantly correlated with tumor size, lymph node status, TNM stage, and worse overall survival among NPC patients. Downregulation of LINC00958 suppressed NPC cell proliferation, migration, and invasion and induced apoptosis in vitro. Additionally, the LINC00958 knockdown impaired tumor growth in vivo. Mechanistically, LINC00958 was found to serve as a molecular sponge of microRNA-625 (miR-625), thereby upregulating NUAK family SNF1-like kinase 1 (NUAK1) in NPC cells. Lastly, rescue experiments validated the involvement of the miR-625–NUAK1 axis in LINC00958-mediated biological functions in NPC.

Conclusion

Our results demonstrated that LINC00958 works as an oncogene in NPC and plays a key role in the malignant phenotype of NPC cells by sponging miR-625 and increasing NUAK1 expression. The LINC00958–miR-625–NUAK1 pathway might be a target for anticancer therapy in patients with NPC.

miR-96-5p promotes the proliferation and migration of ovarian cancer cells by suppressing Caveolae1

BACKGROUND

Ovarian cancer (OC) is the second most common gynaecological malignancy. MicroRNAs (miRNAs) have been found to be aberrantly expressed in OC tissue and have been proposed as biomarkers and therapeutic targets for OC.

RESULTS

In this study, we found that miR-96-5p was up-regulated in OC tissues and OC cells compared to normal ovarian tissues and epithelial cell line. And, miR-96-5p was also up-regulated in the serum samples from OC patients compared to health participants. In addition, there was a positive correlation of miR-96-5p levels between OC tissues and serum samples. At the cellular level, overexpression of miR-96-5p promoted cell proliferation and migration in OC cells. Moreover, we further validated Caveolae1 (CAV1) as the direct target of miR-96-5p in OC cells through luciferase activity assays and western blot. CAV1 was obvious low expression in OC tissues. The overexpression of CAV1 abrogated the promotion of miR-96-5p on the OC cells proliferation and migration. Finally, we found that AKT signaling pathway was involved in this process. MiR-96-5p inhibited the phosphorylation of AKT and expression of down-stream proteins Cyclin D1 and P70 by targeting CAV1.

CONCLUSIONS

The above findings suggested that targeting miR-96-5p may be a promising strategy for OC treatment.

MicroRNA-421 inhibition alleviates bronchopulmonary dysplasia in a mouse model via targeting Fgf10

Bronchopulmonary dysplasia (BPD) is a common and refractory disease affecting newborn children and infants with alveolar dysplasia and declined pulmonary function. Several microRNAs (miRNAs) have been found to be differentially expressed in BPD progression. This study further explores the role of miR-421 via fibroblast growth factor 10 (Fgf10) in mice with BPD. A mouse model of BPD was established through the induction of hyperoxia, in which the expression pattern of miR-421 and Fgf10 was identified. Furthermore, adenovirus-packed vectors were injected in mice to intervene miR-421 and Fgf10 expression, including miR-421 mimics or inhibitors, and si-Fgf10 to explore the role of miR-421 and Fgf10 in BPD. The target relationship between miR-421 and Fgf10 was investigated. Inflammatory response and cell apoptosis were observed in the mice, with inflammatory cytokines and apoptosis-related factors detected by applying Reverse transcription quantitative polymerase chain reaction, Western blot analysis, and enzyme-linked immunosorbent assay. Fgf10 was confirmed as a target gene of miR-421. Elevated expression of miR-421 was evident, while Fgf10 was poorly expressed in BPD. upregulation of miR-421 and silence of Fgf10 aggravated inflammatory response in lung tissue and promoted lung cell apoptosis in BPD. The aforementioned alterations could be reversed by downregulation of miR-421. Collectively, inhibition of miR-421 can assist in the development of BPD in mice BPD by upregulating Fgf10. Therefore, the present study provides a probable target for the treatment of BPD.

The effect and mechanism of miR-210 in down-regulating the autophagy of lung cancer cells

This project aims to investigate the roles of miR-210 in autophagy of lung cancer cells and the related mechanism. The expressions of miR-210 and ATG7 in 30 cancer tissues and the adjacent tissues in patients with lung cancer were compared using RT-qPCR methods, Western Blot assay was carried out to test the expression of ATG7 in protein. Moreover, the dual luciferase reporter gene assay system was used to confirm ATG7 is a target gene of miR-210. Furthermore, lung cancer cell line A549 was transfected with either miR-210 mimics or inhibitors and RT-qPCR methods was used to detect the expression of miR-210 and ATG7. Next, MTT assay was used to examine the effect of miR-210 on the growth of the lung cancer cells, and finally, the expression of autophagy related genes, ATG7, LC3-II/LC3-I and Beclin-1 were detected by Western Blot and ICC assay. We observed that miR-210 was significantly increased and ATG7 was markedly decreased in cancer tissue of patients with lung cancer compared with normal tissue. Moreover, results of dual luciferase reporter assay indicated that ATG7 is a direct target of miR-210. Next, transfection of miR-210 mimics in lung cancer cells induced significant increase in cell proliferation, and transfection of miR-210 inhibitors lead to inhibited cell proliferation. Furthermore, over-expression of miR-210 induced marked decrease in the expression of ATG7, LC3-II/LC3-I and Beclin-1, while transfection of miR-210 inhibitors induced significant increase in the expression of ATG7, LC3-II/LC3-I and beclin-1. Our results suggested that miR-210 plays a great role in autophagy of lung cancer cell by targeting ATG7.

MicroRNA-493-5p inhibits proliferation and metastasis of osteosarcoma cells by targeting Kruppel-like factor 5

Osteosarcoma, including spinal osteosarcoma, has properties of high degree of malignancy, high rate of recurrence, and high incidence of metastasis. microRNAs can exert oncogenic or tumor suppressive roles in cancer cells. This study explored the effects of microRNA-493-5p (miR-493-5p) on osteosarcoma cell viability, migration, invasion, and apoptosis, as well as the underlying possible mechanism. First, the expression of miR-493-5p in osteosarcoma tissues and cells was detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Then, the effects of miR-493-5p overexpression (or suppression) on osteosarcoma cell viability, migration, invasion, and apoptosis, as well as Kruppel-like factor 5 (KLF5) expression, were assessed using the Cell Counting Kit-8 assay, two-chamber transwell assay, Annexin V-FITC/PI apoptosis detection kit, qRT-PCR, and western blotting, respectively. Finally, the roles of KLF5 in miR-493-5p suppression-induced U20S cell viability, migration, and invasion enhancement, as well as the PI3K/AKT pathway activation, were evaluated. We found that miR-493-5p had lower expression in tumor tissues of spinal osteosarcoma and osteosarcoma cells. Overexpression of miR-493-5p inhibited osteosarcoma U20S cell viability, migration, and invasion, but induced cell apoptosis. On the contrary, suppression of miR-493-5p-promoted U20S cell viability, migration, and invasion. KLF5 was a direct target gene of miR-493-5p, which participated in the effects of miR-493-5p on U20S cell viability, migration, invasion, and apoptosis. Furthermore, suppression of the miR-493-5p activated PI3K/AKT pathway in U20S cells by upregulating KLF5. In conclusion, we revealed that miR-493-5p exerted tumor suppressive roles in spinal osteosarcoma and osteosarcoma cells. Overexpression of miR-493-5p inhibited proliferation and metastasis of osteosarcoma cells by downregulating KLF5 and inactivating the PI3K/AKT signaling pathway.

Modulation of miR-10a-mediated TGF-β1/Smads signaling affects atrial fibrillation-induced cardiac fibrosis and cardiac fibroblast proliferation

Atrial fibrillation (AF) rat models and rat cardiac fibroblasts (CFs) with overexpressed or inhibited miR-10a were used to investigate the possible role of miR-10a-mediated transforming growth factor-β (TGF-β1)/Smads signaling in cardiac fibrosis and fibroblast proliferation in rats with AF. Gene ontology and pathway enrichment analyses were used to identify the possible function of miR-10a in cardiac fibrosis. The results showed that overexpressed miR-10a significantly prolonged the duration of AF, further elevated the collagen volume fraction (CVF), and increased the viability of CFs in AF rats; these findings were in contrast with the findings for rats with inhibition of miR-10a (all P<0.05). Moreover, miR-10a overexpression could promote miR-10a, collagen-I, collagen III, α-SMA, and TGF-β1 protein expression and increase the levels of hydroxyproline but reduced Smad7 protein expression in atrial tissues and CFs in AF rats. Not surprisingly, inhibiting miR-10a led to completely contrasting results (all P<0.05). Moreover, TGF-β1 treatment could reverse the inhibitory effect of miR-10a down-regulation on cardiac fibrosis in CFs. Bioinformatics analysis and luciferase reporter assay results demonstrated that miR-10a bound directly to the 3′-UTR of BCL6, which is involved in cell growth and proliferation. Thus, our study indicate that down-regulation of miR-10a may inhibit collagen formation, reduce atrial structure remodeling, and decrease proliferation of CFs, eventually suppressing cardiac fibrosis in AF rats via inhibition of the TGF-β1/Smads signaling pathway.

MicroRNAs and their role in environmental chemical carcinogenesis

MicroRNAs (miRNAs) are a class of small, noncoding RNA species that play crucial roles across many biological processes and in the pathogenesis of major diseases, including cancer. Recent studies suggest that the expression of miRNA is altered by certain environmental chemicals, including metals, organic pollutants, cigarette smoke, pesticides and carcinogenic drugs. In addition, extensive studies have indicated the existence and importance of miRNA in different cancers, suggesting that cancer-related miRNAs could serve as potential markers for chemically induced cancers. The altered expression of miRNA was considered to be a vital pathogenic role in xenobiotic-induced cancer development. However, the significance of miRNA in the etiology of cancer and the exact mechanisms by which environmental factors alter miRNA expression remain relatively unexplored. Hence, understanding the interaction of miRNAs with environmental chemicals will provide important information on mechanisms underlying the pathogenesis of chemically induced cancers, and effectively diagnose and treat human cancers resulting from chronic or acute carcinogen exposure. This study presents the current evidence that the miRNA deregulation induced by various chemical carcinogens, different cancers caused by environmental carcinogens and the potentially related genes in the onset or progression of cancer. For each carcinogen, the specifically expressed miRNA may be considered as the early biomarkers of the cancer process. In this review, we also summarize various target genes of the altered miRNA, oncogenes or anti-oncogenes, and the existing evidence regarding the gene regulation mechanisms of cancer caused by environmentally induced miRNA alteration. The future perspective of miRNA may become attractive targets for the diagnosis and treatment of carcinogen-induced cancer.

Clinical significance of miR-195 in hepatocellular carcinoma and its biological function in tumor progression

Background

Hepatocellular carcinoma (HCC) is one of the most lethal cancer types all over the world. Chronic viral hepatitis B and hepatitis C are risk factors that are associated with the development of HCC. The aim of this study is to identify the diagnostic role of serum miR-195 in HCC.

Patients and methods

The expression levels of miR-195 were detected in 120 HCC patients, 64 hepatitis only patients, and 118 healthy control as well as 4 HCC cell lines, by using quantitative real-time PCR. The association of miR-195 with clinicopathological parameters of patients was analyzed with the chi-squared test. The receiver operating characteristic (ROC) curve was adopted to estimate the potential diagnostic value of miR-195. The cell experiments were carried out to verify the functional role of miR-195.

Results

The expression of miR-195 was downregulated in HCC cells and serum of patients compared to the controls (all P<0.05). The miR-195 expression was associated with lymph node metastasis and TNM stage. The ROC curve analysis showed that miR-195 may be a noninvasive diagnostic marker for patients. By using miR-195 mimic or inhibitor, cell proliferation, migration, and invasion were inhibited by miR-195 overexpression but promoted by reduced expression of miR-195.

Conclusion

The downregulation of miR-195 may serve as a novel diagnostic biomarker for differentiating HCC patients, healthy individuals, and hepatitis patients, and may involve in the tumor progression of HCC.

Network-based integration of mRNA and miRNA profiles reveals new target genes involved in pancreatic cancer

Pancreatic cancer is regarded as the most fatal and aggressive malignancy cancer due to its low 5-year survival rate and poor prognosis. The approaches of early diagnosis and treatment are limited, which makes it urgent to identify the complex mechanism of pancreatic oncogenesis. In this study, we used RNA-seq to investigate the transcriptomic (mRNA and miRNA) profiles of pancreatic cancer in paired tumor and normal pancreatic samples from ten patients. More than 1000 differentially expressed genes were identified, nearly half of which were also found to be differentially expressed in the majority of examined patients. Functional enrichment analysis revealed that these genes were significantly enriched in multicellular organismal and metabolic process, secretion, mineral transport, and intercellular communication. In addition, only 24 differentially expressed miRNAs were found, all of which have been reported to be associated with pancreatic cancer. Furthermore, an integrated miRNA-mRNA interaction network was generated using multiple resources. Based on the calculation of disease correlation scores developed here, several genes present in the largest connected subnetwork, such as albumin, ATPase H⁺ /K⁺ exchanging alpha polypeptide and carcinoembryonic antigen-related cell adhesion molecule 1, were considered as novel genes that play important roles in the development of pancreatic cancer. Overall, our data provide new insights into further understanding of key molecular mechanisms underlying pancreatic tumorigenesis.

MicroRNA-379 suppresses cell proliferation, migration and invasion in nasopharyngeal carcinoma by targeting tumor protein D52

MicroRNAs (miRs) have been demonstrated to be important regulators of malignant behavior in nasopharyngeal carcinoma (NPC) tumorigenesis. The present study aimed to investigate the biological roles and underlying mechanisms of miR-379 in NPC. The study initially observed that miR-379 was significantly downregulated in NPC clinical tissues and cell lines using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Next, gain-of-function assays were performed on human the NPC cell lines, C666-1 and 5-8F, including MTT, colony formation and transwell migration assays. The results indicated that ectopic expression of miR-379 suppressed the NPC cell proliferation, colony formation, migration and invasion in vitro. In addition, tumor protein D52 (TPD52) was identified as a direct target of miR-379 by a dual-luciferase reporter assay, while overexpression of miR-379 markedly reduced TPD52 expression at the mRNA and protein levels, as determined by RT-qPCR and western blot analysis, respectively. Furthermore, silencing of TPD52 significantly inhibited the C666-1 cell proliferation, migration and invasion. These findings suggest that miR-379 negatively regulates the growth and migration of NPC cells by downregulating TPD52 expression, while modulation of miR-379 expression may be a therapeutic strategy for NPC.

MicroRNA-590-5p regulates cell viability, apoptosis, migration and invasion of renal cell carcinoma cell lines through targeting ARHGAP24

Renal cell carcinoma (RCC) is the leading cause of death in renal malignancies. MicroRNA-590-5p (miR-590-5p) is of great importance in the processes of many cancers regarding regulation of cancer cell invasion and proliferation. In our study, alternation of miR-590-5p expression in RCC cell lines through transfection with pre-miR-590-5p (up-regulation) or anti-miR-590-5p (down-regulation) was performed. Apoptosis and viability of RCC cell lines were measured by flow cytometry and CCK-8 analysis, respectively. Cell invasion and migration were estimated by Transwell assay. The association of miR-590-5p with ARHGAP24 expression was evaluated using luciferase assays, real-time PCR and western blot assay. The expressions of apoptosis and migration-related protein were also measured by western blotting. We found that pre-miR-590-5p transfection in Caki-2 and 786-O cells showed significant increases in cell viability, invasion and migration, which were accompanied by decreased cell apoptosis, while anti-miR-590-5p transfection obviously inhibited the cell viability, migration and invasion of Caki-2 and 786-O cells as well as induced apoptosis, compared with the negative control group. Furthermore, bioinformatics combined with luciferase reporter assays indicated that ARHGAP24 is directly targeted by miR-590-5p. ARHGAP24 overexpression in 786-O and Caki-2 cells phenocopied the effects of anti-miR-590-5p transfection along with enhanced expression of active Caspase-3 and Bax/Bcl-2 ratio as well as decreased expression of MMP-2 and MMP-9. These findings suggested that miR-590-5p/ARHGAP24 seems to function as a potentially beneficial target for RCC treatment.

LncRNA Snhg1, a non-degradable sponge for miR-338, promotes expression of proto-oncogene CST3 in primary esophageal cancer cells

Competing endogenous RNA (ceRNA) is a newly proposed mechanism that describes a crosstalk among lncRNAs, mRNAs and their shared miRNAs. In this study, the role of miR-338-3p (miR-338) in the progression of esophageal cancer and its involve in the ceRNA regulatory circuit lncRNA-Snhg1/CST3 were explored. MiR-338 displayed a 30% decreased expression in esophageal squamous cell carcinoma tissues compared with the adjacent. Then, proto-oncogene CST3 was predicted and validated as a target gene of miR-338. Gain-and-loss-function experiments indicated that miR-338 suppressed expression of CST3 protein (also Cystatin C, CysC), promoted expression of apoptotic proteins caspase-8/3, attenuated esophageal carcinoma cell growth and induced its apoptosis. In addition, lncRNA-Snhg1 was significantly upregulated in esophageal carcinoma tissues and promoted esophageal carcinoma cell growth. Furthermore, our results from bioinformatics, luciferase reporter gene and RNA pull-down assays indicated that Snhg1 could be directly bound by miR-338. Snhg1 acted as a non-degradable sponge to relieve the suppression on CST3 caused by miR-338. In conclusion, lncRNA-Snhg1 promoted cell proliferation by acting as a non-degradable sponge for the tumor suppressor miR-338 in esophageal cancer cells.

MiR-422a targets MAPKK6 and regulates cell growth and apoptosis in colorectal cancer cells

The important role of miR-422a in tumor has been reported in several studies. Recent research discovered that the expression of miR-422a was significantly decreased in colorectal cancer tissues, providing miR-422a as a tumor suppressor in CRC. However, the concrete mechanism of miR-422a regulating CRC cell is still unclear. In this study, we demonstrated that miR-422a could inhibit CRC cell growth and promote cell apoptosis via in vitro analyses. Moreover, computational methods were adopted to identify the targets of miR-422a. We found MAPKK6 was the direct target of miR-422a. Consequently, we further elucidated that miR-422a inhibited CRC cell growth and induced cell apoptosis by inhibiting p38/MAPK pathway. Besides that, we established the tumor xenograft model using nude mice and the inhibitory effects on tumor volumes and weights by miR-422a mimic transfection were also detected. Taken together, these findings demonstrated miR-422a exerted anti-cancer activities on CRC, which could be potentially used for CRC prognosis prediction and treatment.

Influence of Adalimumab on the Expression Profile of Genes Associated with the Histaminergic System in the Skin Fibroblasts In Vitro

Objective

The aim of this study was to evaluate the influence of adalimumab on expression profile of genes associated with the histaminergic system in Normal Human Dermal Fibroblast (NHDF) cells stimulated with 8.00 μg/ml of adalimumab and the identification of miRNAs regulating these genes' expression.

Methods

NHDFs were cultured with or without the presence of adalimumab for 2, 8, and 24 hours. The expression profile of genes and miRNA were determined with the use of microarray technology.

Results

Among 22283 ID mRNA, 65 are associated with the histaminergic system. It can be observed that 15 mRNAs differentiate NHDFs cultures with adalimumab form control. The analysis of miRNAs showed that, among 1105 ID miRNA, 20 miRNAs are differentiating in cells treated with adalimumab for 2 hours, 9 miRNA after 8 hours, and only 3 miRNAs after 24 hours.

Conclusion

It was also determined that miRNAs play certain role in the regulation of the expression of genes associated with the histaminergic system. The results of this study confirmed the possibility of using both genes associated with this system as well as miRNAs regulating their expression, as complementary molecular markers of sensitivity to the adalimumab treatment.

Serological under expression of microRNA-21, microRNA-34a and microRNA-126 in colorectal cancer

PURPOSE

This paper describes the ability of miRNA value predict oncological outcomes in CRC patients and correlates to clinical and pathologic variables.

METHODS

We prospectively analyzed the serological expression of microRNA-21, microRNA-34a, and microRNA-126 in 37 stage II - IV CRC patients and correlate to seven fit counterparts. Serological microRNAs were extracted using the miRNeasy Mini Kit(r) (Qiagen, Hilden, Germany). Quantification of microRNAs was performed using TaqMan Master Mix(r) reagent (Applied Biosystems, USA).

RESULTS

We obtained serological underexpression microRNA-21, microRNA-34a, and microRNA-126 in CRC group. However, miRNAs serological values do not impact prognosis. Furthermore, miRNAs was not influenced by CEA values, TNM staging, and histological subtype.

CONCLUSION

Despite lower expression of miR-21, miR-34a and miR-126 in the CRC group, no association with poor prognosis was found.

Meta-analysis of the differentially expressed microRNA profiles in nasopharyngeal carcinoma

MicroRNAs(miRNAs), as non-coding molecules, were proved to be correlated with gene expression in naspharyngeal carcinoma (NPC) development. In this research, a comprehensive meta-analysis of eight independent miRNA expression studies in NPC was preformed by using robust rank aggregation method (RRA), which contained a total of 775 tumor and 227 non-cancerous samples. There were 7 significant dysregulated miRNAs identified including three increased (miR-483–5p, miR-29c-3p and miR-205–5p) and four decreased (miR-29b-3p, let-7d-5p, miR-100– 5p and let-7g-5p) miRNAs. Subsequently, the miRNA target prediction and pathway enrichment analysis were carried out to find out the biological and functional relevant genes involved in the meta-signature miRNA regulation. Finally, several signaling and cancer pathogenesis pathways were suggested to be more frequently associated with the progression of NPC. In this research the meta-signature miRNA identified may be used to develop a series of diagnostic and prognostic biomarkers for NPC that serve specificity for use in clinics.

Circulating microRNA-122 as Potential Biomarker for Detection of Testosterone Abuse

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and thus influence many cellular and physiological processes. miRNAs are also present in cell-free body fluids such as plasma or serum, and these circulating miRNAs are very stable, sensitive, and specific biomarkers of pathophysiological states. In this study, we investigated whether circulating miRNAs could serve as biomarkers of exogenous testosterone administration. Misuse of testosterone as a performance-enhancing drug is thought to be widespread in sports. Detection of testosterone through the urinary steroid profile of the Athlete Biological Passport faces several obstacles, indicating that new biomarkers are required. To this end, we analyzed plasma miRNA levels by high-throughput quantitative real-time PCR. Plasma samples were obtained before and at several time points after transdermal and oral testosterone administration. Screening identified three potential candidate miRNAs that were altered by both routes of testosterone administration. Longitudinal monitoring of these candidates revealed that variation in two of them (miR-150 and miR-342), relative to the corresponding levels in control samples, was testosterone-independent. However, levels of the liver-specific miR-122 increased 3.5-fold 1 day after drug intake. Given that testosterone is metabolized by the liver, this observation suggests that miR-122 in cell-free fluids may be used as a sensitive biomarker of testosterone misuse via multiple dosing routes and could therefore be integrated into a blood-based multiparametric follow-up.

miR-9 Modulates Osteosarcoma Cell Growth by Targeting the GCIP Tumor Suppressor

Osteosarcoma is the most common primary bone tumor in humans, especially in childhood. However, the genetic etiology for its pathogenesis remains elusive. It is known that microRNAs (miRNAs) are involved in the development of tumor progression. Here we show that microRNA-9 (miR-9) is a potential oncogene upregulated in osteosarcoma cells. Knockdown of miR-9 in osteosarcoma resulted in suppressed colony formation and cell proliferation. Further study identified GCIP, a Grap2 and cyclin D interacting protein, as a direct target of miR- 9. In addition, GCIP overexpression activated retinoblastoma 1 (Rb) and suppressed E2F transcriptional target expression in osteosarcoma cells. Moreover, GCIP depletion reversed miR-9 knockdown induced colony formation and cell proliferation suppression. In sum, these results highlight the importance of miR-9 as an oncogene in regulating the proliferation of osteosarcoma by directly targeting GCIP and may provide new insights into the pathogenesis of osteosarcoma.

microRNA-29b: an emerging player in human cancer

MicroRNAs (miRNAs) are ubiquitously expressed small, non-coding RNAs that negatively regulate gene expression at a post transcriptional/translational level. They have emerging as playing crucial roles in cancer at all stages ranging from initiation to metastasis. As a tumor suppressor miRNA, aberrant expression of microRNA-29b (miR-29b) has been detected in various types of cancer, and its disturbance is related with tumor development and progression. In this review, we summarize the latest findings with regard to the tumor suppressor signature of miR-29b and its regulatory mechanisms. Our review highlights the diverse relationships between miR-29b and its target genes in malignant tumors.

Mangiferin regulates proliferation and apoptosis in glioma cells by induction of microRNA-15b and inhibition of MMP-9 expression

Mangiferin, a flavonoid extracted from the leaves of the Anacardiaceae plant, the mango tree, has physiological activity and pharmacological effects in many aspects. The present study aimed to clarify the effect of mangiferin on proliferation and apoptosis of glioma cells and the mechanism of these curative effects of mangiferin. In this experiment, we detected the proliferation using 3-(4,5-dimethylthylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay. Then, cell apoptosis of U87 glioma cells was measured with the Annexin V-FITC/propidium iodide (PI) apoptosis detection kit, DAPI staining assay and the caspase-3 and caspase-9 activity assay kit. Next, quantitative real-time PCR and gelatin zymography were used to analyze the expression of microRNA-15b (miR-15b) and matrix metalloproteinase-9 (MMP-9), respectively. MMP-9 agonist, miR-15b mimics and anti-miR-15b mimics were added to the U87 glioma cells for elucidating the mechanisms involved in the curative effects of mangiferin. In the present study, mangiferin notably restrained the proliferation and increased the apoptosis of the U87 glioma cells. Meanwhile, mangiferin specifically promoted the expression of miR-15b and suppressed the level of MMP-9 in the U87 glioma cells. miR-15b regulated the expression of MMP-9 in the U87 glioma cells. MMP-9 agonist and anti-miR‑15b reduced the curative effects of mangiferin in the U87 glioma cells. In summary, mangiferin regulates proliferation and apoptosis in glioma cells by induction of miR-15b and inhibition of MMP-9 expression.

Network analysis of microRNAs, genes and their regulation in mantle cell lymphoma

The pathogenesis of mantle cell lymphoma, a special subtype of lymphoma that is invasive and indolent and has a median survival of 3 to 4 years, is still partially unexplained. Much research about genes and miRNAs has been conducted in recent years, but interactions and regulatory relations of genetic elements which may play a vital role in genesis of MCL have attracted only limited attention. The present study concentrated on regulatory relations about genes and miRNAs contributing to MCL pathogenesis. Numerous experimentally validated raw data were organized into three topology networks, comprising differentially expressed, associated and global examples. Comparison of similarities and dissimilarities of the three regulating networks, paired with the analysis of the interactions between pairs of elements in every network, revealed that the differentially expressed network illuminated the carcinogenicity mechanism of MCL and the related network further described the regulatory relations involved, including prevention, diagnosis, development and therapy. Three kinds of regulatory relations for host genes including miRNAs, miRNAs targeting genes and genes regulating miRNAs were concluded macroscopically. Regulation of the differentially expressed miRNAs was also analyzed, in terms of abnormal gene expression affecting the MCL pathogenesis. Special regulatory relations were uncovered. For example, auto-regulatory loops were found in the three topology networks, key pathways of the nodes being highlighted. The present study focused on a novel point of view revealing important influencing factors for MCL pathogenesis.