miR-888 functions as an oncogene and predicts poor prognosis in colorectal cancer

Differential expression of miRNA in histological subtype of Wilms tumor

INTRODUCTION

Wilms tumor is the most common renal malignancy in children and difficult to differentiate from other paediatric abdominal tumors radiologically, necessitating an invasive procedure for diagnosis. Previous studies have shown the potential role of miRNA as biomarkers for diagnosis, histological subtyping and prognosis. In this study, we are exploring the role of miRNA in the histological subtyping of Wilms tumor in the Indian population.

MATERIALS AND METHODS

A total of 15 cases of Wilms tumor were evaluated for global miRNA expression analysis by microarray. Total RNA was extracted from fresh frozen tumor and miRNA expression analysis was performed using Agilent platform. Unsupervised clustering was done to analyse the data.

RESULTS

Using unpaired student T test, top 10 significantly differentially expressed miRNA were selected which could differentiate among different histological subtypes by unsupervised hierarchical clustering and principal component analysis. The presence of necrosis, heterologous differentiation led to change in miRNA expression profile and led to a distinct cluster formation.

CONCLUSIONS

A panel of 5 miRNAs (miR1, 133b, 299-3p, 499a-5p, 491-3p) could differentiate among different histological subtypes of Wilms tumor, thus avoiding an invasive procedure in children, however, further confirmation using real time PCR analysis will be needed.

miR-765 Acts as a Tumor Promoter and Indicates Poor Prognosis in Non-Small Cell Lung Cancer

PURPOSE

Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-related death worldwide with poor prognosis. Accumulating evidence indicates that miR-765 is an important regulator in the progression and prognosis of various cancers. In this study, the function in the progression and prognosis of NSCLC was investigated.

PATIENTS AND METHODS

The expression of miR-765 in NSCLC was analyzed by qRT-PCR. The effect of miR-765 on cell proliferation, migration, and invasion of NSCLC was evaluated by CCK8 and Transwell assay. Kaplan-Meier analysis and Cox regression analysis were employed to assess the prognostic value of miR-765.

RESULTS

The results demonstrated the significant upregulation of miR-765 in NSCLC tissues and cell lines relative to normal tissues and cells. High miR-765 expression was significantly correlated with the TNM stage of patients. Patients with high miR-765 expression showed a poorer prognosis than that of patients with low miR-765 expression. Cox analysis indicated that miR-765 could be considered as an independent prognostic factor for NSCLC. Additionally, the upregulation of miR-765 was revealed to promote NSCLC cell proliferation, migration, and invasion by targeting BMP6.

CONCLUSION

The overexpression of miR-765 in NSCLC was associated with TNM stage and poor prognosis of patients. miR-765 served as a tumor promoter of NSCLC by regulating BMP6. These findings provide a potential biomarker and therapeutic target for the prognosis and treatment of NSCLC.

ChrXq27.3 miRNA cluster functions in cancer development

MicroRNAs (miRNAs) regulate the expression of their target genes post-transcriptionally; thus, they are deeply involved in fundamental biological processes. miRNA clusters contain two or more miRNA-encoding genes, and these miRNAs are usually coexpressed due to common expression mechanisms. Therefore, miRNA clusters are effective modulators of biological pathways by the members coordinately regulating their multiple target genes, and an miRNA cluster located on the X chromosome q27.3 region has received much attention in cancer research recently. In this review, we discuss the novel findings of the chrXq27.3 miRNA cluster in various types of cancer.

The chrXq27.3 miRNA cluster contains 30 mature miRNAs synthesized from 22 miRNA-encoding genes in an ~ 1.3-Mb region. The expressions of these miRNAs are usually negligible in many normal tissues, with the male reproductive system being an exception. In cancer tissues, each miRNA is dysregulated, compared with in adjacent normal tissues. The miRNA-encoding genes are not uniformly distributed in the region, and they are further divided into two groups (the miR-506-514 and miR-888-892 groups) according to their location on the genome. Most of the miRNAs in the former group are tumor-suppressive miRNAs that are further downregulated in various cancers compared with normal tissues. miR-506-3p in particular is the most well-known miRNA in this cluster, and it has various tumor-suppressive functions associated with the epithelial–mesenchymal transition, proliferation, and drug resistance. Moreover, other miRNAs, such as miR-508-3p and miR-509-3p, have similar tumor-suppressive effects. Hence, the expression of these miRNAs is clinically favorable as prognostic factors in various cancers. However, the functions of the latter group are less understood. In the latter group, miR-888-5p displays oncogenic functions, whereas miR-892b is tumor suppressive. Therefore, the functions of the miR-888–892 group are considered to be cell type- or tissue-specific.

In conclusion, the chrXq27.3 miRNA cluster is a critical regulator of cancer progression, and the miRNAs themselves, their regulatory mechanisms, and their target genes might be promising therapeutic targets.

Tissue micro-RNAs associated with colorectal cancer prognosis: a systematic review

Colorectal cancer (CRC) is a multifactorial disease commonly diagnosed worldwide, with high mortality rates. Several studies demonstrate important associations between differential expression of micro-RNAs (miRs) and the prognosis of CRC. The present study aimed to identify differentially expressed tissue miRs associated with prognostic factors in CRC patients, through a systematic review of the Literature. Using the PubMed database, Cochrane Library and Web of Science, studies published in English evaluating miRs differentially expressed in tumor tissue and significantly associated with the prognostic aspects of CRC were selected. All the included studies used RT-PCR (Taqman or SYBR Green) for miR expression analysis and the period of publication was from 2009 to 2018. A total of 115 articles accomplished the inclusion criteria and were included in the review. The studies investigated the expression of 100 different miRs associated with prognostic aspects in colorectal cancer patients. The most frequent oncogenic miRs investigated were miR-21, miR-181a, miR-182, miR-183, miR-210 and miR-224 and the hyperexpression of these miRs was associated with distant metastasis, lymph node metastasis and worse survival in patients with CRC. The most frequent tumor suppressor miRs were miR-126, miR-199b and miR-22 and the hypoexpression of these miRs was associated with distant metastasis, worse prognosis and a higher risk of disease relapse (worse disease-free survival). Specific tissue miRs are shown to be promising prognostic biomarkers in patients with CRC, given their strong association with the prognostic aspects of these tumors, however, new studies are necessary to establish the sensibility and specificity of the individual miRs in order to use them in clinical practice.

Mi-RNA-888-5p Is Involved in S-Adenosylmethionine Antitumor Effects in Laryngeal Squamous Cancer Cells

Simple Summary

Laryngeal Squamous Cell Carcinoma (LSCC) is a leading cause of cancer-related death with a strong interest in identifying and developing new treatments. MicroRNAs (miRNAs) have emerged as one of the most important determinants of neoplastic transformation and progression. miRNA modulation causes significant antitumor effects both in vitro and in vivo and miRNA regulation by natural compounds, represents a promising approach in the field of cancer research. S-Adenosylmethionine (AdoMet), a natural compound and a nutritional supplement, is well known for its antiproliferative and pro-apoptotic effects in many kinds of human tumors. Here, we report that AdoMet induces ER-stress and autophagy paralleled by miR-888-5p downregulation and MYCBP and CDH1 increased expression in Laryngeal Squamous Cancer Cells (LSCC). This study contributes to understanding the mechanisms by which AdoMet exerts its effects in LSCC, suggesting the use of AdoMet as an attractive miRNA-mediated chemopreventive and therapeutic strategy against cancer.

Abstract

(1) Purpose: The methyl donor S-Adenosylmethionine (AdoMet) has been widely explored as a therapeutic compound, and its application-alone or in combination with other molecules-is emerging as a potential effective strategy for the treatment and chemoprevention of tumours. In this study, we investigated the antitumor activity of AdoMet in Laryngeal Squamous Cell Carcinoma (LSCC), exploring the underlying mechanisms. (2) Results: We demonstrated that AdoMet induced ROS generation and triggered autophagy with a consistent increase in LC3B-II autophagy-marker in JHU-SCC-011 and HNO210 LSCC cells. AdoMet induced ER-stress and activated UPR signaling through the upregulation of the spliced form of XBP1 and CHOP. To gain new insights into the molecular mechanisms underlying the antitumor activity of AdoMet, we evaluated the regulation of miRNA expression profile and we found a downregulation of miR-888-5p. We transfected LSCC cells with miR-888-5p inhibitor and exposed the cells to AdoMet for 48 and 72 h. The combination of AdoMet with miR-888-5p inhibitor synergistically induced both apoptosis and inhibited cell migration paralleled by the up-regulation of MYCBP and CDH1 genes and of their targets. (3) Conclusion: Overall, these data highlighted that epigenetic reprogramming of miRNAs by AdoMet play an important role in inhibiting apoptosis and migration in LSCC cell lines.

Clinical significance of serum miR-888-5p in patients with primary hepatocellular carcinoma

BACKGROUND

MiR-888-5p is highly expressed in hepatocellular carcinoma (HCC) tissues and cell lines, and it can promote tumor invasion and metastasis and is related to disease stage and poor prognosis. However, the clinical value of serum miR-888-5p levels in the diagnosis and prognosis of HCC remains unclear.

AIM

To detect serum miR-888-5p in patients with HCC and investigate its diagnostic value and correlation with clinical characteristics of HCC.

METHODS

A total of 197 subjects were enrolled, consisting of 68 HCC patients, 46 chronic hepatitis B (CHB) patients, 43 liver cirrhosis (LC) patients, and 40 healthy volunteers. Serum miR-888-5p levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The diagnostic value of miR-888-5p and its correlation with clinical features were assessed.

RESULTS

Compared with CHB patients, LC patients, and healthy controls, serum miR-888-5p increased significantly in HCC patients (P < 0.05). Receiver operating characteristic curve (ROC) analysis demonstrated that the area under the ROC curve (AUC) of miR-888-5p combined with alpha-fetoprotein (AFP) in discriminating HCC patients from healthy controls was 0.907 (sensitivity: 91.18%; specificity: 72.50%), higher than that of either AFP (AUC = 0.819; sensitivity: 73.53%; specificity: 97.50%) or miR-888-5p alone (AUC = 0.737; sensitivity: 79.41%; specificity: 62.50%). Serum miR-888-5p maintained its diagnostic efficiency in AFP negative HCC patients with an AUC of 0.793 (sensitivity: 90.90%; specificity: 62.50%). Serum miR-888-5p levels were significantly associated with pulmonary metastasis (P = 0.01) of HCC.

CONCLUSION

Serum miR-888-5p has high diagnostic value for HCC, and combined detection of serum miR-888-5p and AFP could improve the diagnostic efficiency. MiR-888-5p also has good diagnostic value for AFP negative HCC, and it is closely related to lung metastasis of HCC. MiR-888-5p is expected to become a new serum marker for early diagnosis and prognosis evaluation of HCC.

Value of microRNAs in diagnosis and prognosis of colorectal cancer

Some new treatment methods have been explored to delay the recurrence of colorectal cancer (CRC). Early diagnosis plays an important role in the improvement of curative effect. The conventional methods used to diagnose and monitor CRC are fecal occult blood test (FOBT) and colonoscopy. However, FOBT has an unsatisfactory sensitivity, while colonoscopy is expensive and invasive. As new biomarkers, microRNAs, which can be detected in CRC tissues, cells, and body fluid as tumor suppressors or oncogenes, can be used in early diagnosis, the monitoring of metastasis and treatment, as well prognostic evaluation of CRC. This article reviews the diagnostic and prognostic value of microRNAs in CRC.

Epigenetic Influences in the Obesity/Colorectal Cancer Axis: A Novel Theragnostic Avenue

The World Health Organization (WHO) considers that obesity has reached proportions of pandemic. Experts also insist on the importance of considering obesity as a chronic disease and one of the main contributors to the worldwide burden of other nontransmissible chronic diseases, which have a great impact on health, lifestyle, and economic cost. One of the most current challenges of biomedical science faces is to understand the origin of the chronic nontransmissible diseases, such as obesity and cancer. There is a large evidence, both in epidemiological studies in humans and in animal models, of the association between obesity and an increased risk of cancer incidence. In the last years, the initial discovery of epigenetic mechanisms represents the most relevant finding to explain how the genome interacts with environmental factors and the ripple effects on disease pathogeneses. Since then, all epigenetic process has been investigated by the scientific communities for nearly two decades to determine which components are involved in this process. DNA/RNA methylation and miRNA are classified as two of the most important representative classes of such epigenetic mechanisms and dysregulated activity of such mechanism can certainly contribute to disease pathogenesis and/or progression especially in tumors. This review article serves to highlight the impact of DNA/RNA methylation and miRNA-based epigenetic mechanism activities in the interplay between obesity and the development and clinical significance of colorectal cancer.