miR-126: An indicator of poor prognosis and recurrence in histologically lymph node-negative gastric cancer

Role of Some microRNA/ADAM Proteins Axes in Gastrointestinal Cancers as a Novel Biomarkers and Potential Therapeutic Targets—A Review

Gastrointestinal (GI) cancers are some of the most common cancers in the world and their number is increasing. Their etiology and pathogenesis are still unclear. ADAM proteins are a family of transmembrane and secreted metalloproteinases that play a role in cancerogenesis, metastasis and neoangiogenesis. MicroRNAs are small single-stranded non-coding RNAs that take part in the post-transcriptional regulation of gene expression. Some ADAM proteins can be targets for microRNAs. In this review, we analyze the impact of microRNA/ADAM protein axes in GI cancers.

Effect of Bone Marrow Mesenchymal Stem Cells (BMSCs) with High miR-183-5p Expression on Ovarian Cancer Cells by Regulating Signal Transducer and Activator of Transcription 3 (STAT3)

Currently, the treatment for ovarian cancer (OC) is not satisfactory. The microRNAs may have an important function in tumor pathogenesis. miR-183-5p involves in several tumors. However, its effect on OC cells is unclear. The BMSCs could regulate the micro-environment of tumor and participate in tumor procession. In this study, effect of BMSCs with highly-expressed miR-183-5p on OC cells was assessed. The BMSCs with highly-expressed miR-183-5p was established and co-cultivated with OC cell line SKOV3 followed by measuring miR-183-5p level by PCR, STAT3 and ADAM9 expression by western blot. miR-183-5p level in OC cells was reduced and further decreased after co-culture with BMSCs along with enhance cell proliferation and upregulated STAT3 expression (P < 0.05). In addition, miR-183-5p level was increased in BMSCs with highly-expressed miR-183-5p and STAT3 expression was reduced along with restrained cell proliferation (P < 0.05). In conclusion, miR-183-5p in OC cells is downregulated and malignant biological behaviors of OC cells are restrained by BMSCs with highly-expressed miR-183-5p possibly through regulating the expression of STAT3.

Low Expression of miR-491-3p Is Correlated with Lymph Node Metastasis in Gastric Cancer

Objective

MiR-491-3p, as a tumor suppressor miRNA, was found decreased in many solid tissues. In this study, we aim to investigate miR-491-3p expression in gastric cancer with or without lymph node metastasis (LNM).

Methods

GSE173215 dataset from Gene Expression Omnibus (GEO) was used to measure miRNA expression from tissue samples of gastric cancer patients. Moreover, gastric tumor tissues (non-LNM: n = 78; LNM: n = 68) were obtained to detect the miR-491-3p expression. Receiver operating characteristic (ROC) curve and Kaplan–Meier (KM) survival analysis, as well as Cox regression analysis, were performed to reveal the role of miR-491-3p in diagnosis and prognosis of gastric cancer.

Results

According to GSE173215 datasets (t = −11.25, adjust P value = 1.30E-06) and our clinical results (0.390 ± 0.193 vs. 0.562 ± 0.166, P < 0.005), the gastric cancer patients with LNM showed lower miR-491-3p expression than those without LNM, demonstrating a high diagnostic efficiency (sensitivity: 74.36%; specificity: 69.12%). In addition, both LNM and low miR-491-3p expression were correlated with the poor prognosis of gastric cancer. Furthermore, the LNM patient with low expression of miR-491-3p had the worse prognosis, but the non-LNM patient with high expression of miR-491-3p had the best prognosis. MiR-491-3p expression (HR = 0.003, 95%CI: 3.35E-04∼0.028) and LNM (HR = 2.326, 95%CI: 1.046∼5.173) were independent risk factors for gastric cancer.

Conclusion

Downregulated miR-491-3p expression was found in gastric cancer, being a high diagnostic efficiency and an independent risk factor for gastric cancer, especially in those having LNM.

Down-regulated expression of miR-99a is associated with lymph node metastasis and predicts poor outcome in stage IB cervical squamous cell carcinoma: a case-control study

Background

Lymph node metastasis (LNM) accounts for the most important route of metastasis for cervical cancer. Yet, the status of LNM is different in patients with similar clinico-pathological variables. It has been revealed that microRNAs are widely involved in the occurrence and development of various malignancies, and the tumor-suppressive or promoting effects of microRNA-99 (miR-99) family have been previously reported. This study sought to investigate the predictive value of miR-99a for lymphogenous spread and its effect on the survival of patients with early-stage cervical squamous cell cancer (CSCC).

Methods

Patients with stage IB squamous cervical cancer who were treated surgically between October 2015 and November 2018 were enrolled. A total of 21 formalin-fixed paraffin-embedded tissues of pathologically confirmed positive lymph nodes were retrieved, and an additional 21 tissues of negative lymph nodes from patients well-matched on baseline characteristics were collected as the control group. TaqMan real-time quantitative polymerase chain reaction was used to examine the expression levels of miR-99a in the samples. Differential expression levels of miR-99a were compared between the 2 groups using independent sample t-test. Furthermore, the associations between miR-99a expression level and clinico-pathological parameters of these 42 patients was evaluated by Chi-square test or Fisher's exact-probability method, and their effects on survival were assessed using Kaplan-Meier product-limit method.

Results

There were no significant differences in baseline clinico-pathological parameters between the 2 groups (P>0.05). The expression levels of miR-99a in the node-positive group and control group were 1.61±3.09 and 16.77±30.40, respectively (P=0.029). Downregulated expression of miR-99a was closely related to depth of invasion (DOI) and lymph-vascular space invasion (P<0.05). Univariate analysis revealed that downregulated miR-99a and deeper DOI were associated with worse 5-year disease-free survival, while multivariate analysis showed that only the expression level of miR-99a was an independent factor for disease-free survival (HR =0.120; 95% CI: 0.015-0.979; P=0.048). Patients with downregulated miR-99a tended to have more unfavorable overall survival, but the difference did not reach statistical significance.

Conclusions

MiR-99a plays an inhibitory role in the pathogenesis of lymph node metastasis and may serve as a novel prognostic biomarker for patients with CSCC.

The Role of Epigenetic Factors in Psoriasis

Psoriasis is a chronic, systemic, immune-mediated disease with an incidence of approximately 2%. The pathogenesis of the disease is complex and not yet fully understood. Genetic factors play a significant role in the pathogenesis of the disease. In predisposed individuals, multiple trigger factors may contribute to disease onset and exacerbations of symptoms. Environmental factors (stress, infections, certain medications, nicotinism, alcohol, obesity) play a significant role in the pathogenesis of psoriasis. In addition, epigenetic mechanisms are considered result in modulation of individual gene expression and an increased likelihood of the disease. Studies highlight the significant role of epigenetic factors in the etiology and pathogenesis of psoriasis. Epigenetic mechanisms in psoriasis include DNA methylation, histone modifications and non-coding RNAs. Epigenetic mechanisms induce gene expression changes under the influence of chemical modifications of DNA and histones, which alter chromatin structure and activate transcription factors of selected genes, thus leading to translation of new mRNA without affecting the DNA sequence. Epigenetic factors can regulate gene expression at the transcriptional (via histone modification, DNA methylation) and posttranscriptional levels (via microRNAs and long non-coding RNAs). This study aims to present and discuss the different epigenetic mechanisms in psoriasis based on a review of the available literature.

Identification of a Novel Prognostic Signature for Gastric Cancer Based on Multiple Level Integration and Global Network Optimization

Gastric Cancer (GC) is a common cancer worldwide with a high morbidity and mortality rate in Asia. Many prognostic signatures from genes and non-coding RNA (ncRNA) levels have been identified by high-throughput expression profiling for GC. To date, there have been no reports on integrated optimization analysis based on the GC global lncRNA-miRNA-mRNA network and the prognostic mechanism has not been studied. In the present work, a Gastric Cancer specific lncRNA-miRNA-mRNA regulatory network (GCsLMM) was constructed based on the ceRNA hypothesis by combining miRNA-target interactions and data on the expression of GC. To mine for novel prognostic signatures associated with GC, we performed topological analysis, a random walk with restart algorithm, in the GCsLMM from three levels, miRNA-, mRNA-, and lncRNA-levels. We further obtained candidate prognostic signatures by calculating the integrated score and analyzed the robustness of these signatures by combination strategy. The biological roles of key candidate signatures were also explored. Finally, we targeted the PHF10 gene and analyzed the expression patterns of PHF10 in independent datasets. The findings of this study will improve our understanding of the competing endogenous RNA (ceRNA) regulatory mechanisms and further facilitate the discovery of novel prognostic biomarkers for GC clinical guidelines.

[Differential expression of miR-126-5p in lung adenocarcinoma and the possible mechanism]

OBJECTIVE

To investigate the differential expression of miR-126-5p in patients with lung adenocarcinoma and explore the possible mechanism.

METHODS

We searched STARBASE database to analyze the differential expression of miR-126-5p between lung adenocarcinoma tissues and normal lung tissues. The prognosis of patients with lung adenocarcinoma was analyzed on Kaplan-Meier Plotter online website, and the survival curves of the patients with different expression levels of miR-126-5p were generated. The target gene of mir-126-5p was predicted by STARBASE database, and the expression level of the target gene and its influence on the patients' prognosis were analyzed using online website tool. We also examined the expression levels of miR-126-5p in peripheral serum of 30 healthy control subjects and 30 patients with lung adenocarcinoma using qPCR.

RESULTS

Analysis of the data from STARBASE database showed a high expression of miR-126-5p in normal lung tissues but a low expression in lung adenocarcinoma tissues. Kaplan-Meier Plotter online analysis based on big data analysis showed that patients with a high expression of miR-126-5p had a better survival prognosis than those with a low expression (HR=0.68, P=0.015). MiR-126-5p was predicted to bind to the 3'UTR region of BRCC3 mRNA, and their expression levels were negatively correlated (r=0.197, P < 0.05). Compared with normal tissues, lung adenocarcinoma tissues expressed high levels of BRCC3, which was associated with a poor prognosis of the patients (HR=1.39, P < 0.05). The serum level of miR-126-5p was significantly higher in healthy control subjects than in patients with lung adenocarcinoma (1.23 ± 0.21 vs 0.63 ± 0.12, P < 0.05).

CONCLUSIONS

The expression level of miR-126-5p is lowered in lung adenocarcinoma tissue, and patients with lung adenocarcinoma have lower serum level of miR-126-5p than healthy subjects. A high expression of miR-126-5p is associated with a more favorable prognosis of the patients than a low expression. miR-126-5p may play a role against cancer by regulating BRCC3.

MicroRNA-449a Is Downregulated in Cervical Cancer and Inhibits Proliferation, Migration, and Invasion

INTRODUCTION

Cervical cancer is one of the most common malignant tumors among women in the world. MicroRNA-449a (miR-449a) has been identified as a tumor suppressor gene in various cancers. Our present study aimed to explore the biological role of miR-449a in cervical cancer.

METHODS

The expression of miR-449a in cervical cancer tissues and cell lines was detected using real-time quantitative PCR. Kaplan-Meier survival analysis and a Cox regression assay were used to identify the prognostic significance of miR-449a in cervical cancer. A CCK-8 assay and a Transwell assay were performed to determine the impact of miR-449a on the proliferation, migration, and invasion of cervical cancer cells.

RESULTS

The expression of miR-449a was decreased in both cervical cancer tissues and cell lines. The decreased expression of miR-449a was significantly associated with lymph node metastasis, differentiation, and FIGO stage, as well as with poor survival. In vitro, transfection of miR-449a mimic into cervical cancer cells inhibited cell proliferation, migration, and invasion.

CONCLUSION

All of the results revealed that miR-449a functions as a suppressor gene and inhibits cell proliferation, migration, and invasion in cervical cancer. In addition, it may serve as a prognostic biomarker for cervical cancer.

Increased expression of miR-601 is associated with poor prognosis and tumor progression of gastric cancer

Background

MicroRNAs (miRNAs) have been considered to participate in many tumorigenesis, including gastric cancer (GC). Abnormal expression of miR-601 has been reported in GC, but its role is not clear. The goal of this study is to explore the expression patterns, clinical value and functional role of miR-601 in GC.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to evaluate the expression level of miR-601. The association between miR-601 expression and overall survival was estimated by the Kaplan-Meier survival method. The significance of different variables with respect to survival was analyzed by using the Cox regression assay. Cell experiments were applied to investigate the functional role of miR-601 in GC.

Results

We found that miR-601 was significantly up-regulated in GC tissues and cells compared with the controls (all P < 0.01). The levels of miR-601 expression were significantly associated with TNM stage, lymph node metastasis, lymphatic invasion, and distant metastasis (all P < 0.05). Kaplan-Meier survival analysis showed that patients in the high miR-601 expression group had poor overall survival (log-rank P = 0.001). Moreover, we confirmed that miR-601, TNM stage, and distant metastasis were independent prognostic factors for GC patients. Overexpression of miR-601 in AGS and SGC-7901 cells by miR-601 mimic transfection significantly promoted the cell proliferation, migration, and invasion (P < 0.05).

Conclusions

The expression level of miR-601 is dramatically up-regulated in GC. The overexpression of miR-601 promotes the tumor progression of GC, and may be a novel prognostic factor for poor survival in GC patients.