miR-150-504-519d inhibits the growth of human colorectal cancer cell line SW48 and downregulates c-FLIP receptor

Molecular detection of exosomal miRNAs of blood serum for prognosis of colorectal cancer

Colorectal cancer (CRC) is the third most common cancer affecting people. The discovery of new, non-invasive, specific, and sensitive molecular biomarkers for CRC may assist in the diagnosis and support therapeutic decision making. Exosomal miRNAs have been demonstrated in carcinogenesis and CRC development, which makes these miRNAs strong biomarkers for CRC. Deep sequencing allows a robust high-throughput informatics investigation of the types and abundance of exosomal miRNAs. Thus, exosomal miRNAs can be efficiently examined as diagnostic biomarkers for disease screening. In the present study, a number of 660 mature miRNAs were detected in patients diagnosed with CRC at different stages. Of which, 29 miRNAs were differentially expressed in CRC patients compared with healthy controls. Twenty-nine miRNAs with high abundance levels were further selected for subsequent analysis. These miRNAs were either highly up-regulated (e.g., let-7a-5p, let-7c-5p, let-7f-5p, let-7d-3p, miR-423-5p, miR-3184-5p, and miR-584) or down-regulated (e.g., miR-30a-5p, miR-99-5p, miR-150-5p, miR-26-5p and miR-204-5p). These miRNAs influence critical genes in CRC, leading to either tumor growth or suppression. Most of the reported diagnostic exosomal miRNAs were shown to be circulating in blood serum. The latter is a novel miRNA that was found in exosomal profile of blood serum. Some of the predicted target genes of highly expressed miRNAs participate in several cancer pathways, including CRC pathway. These target genes include tumor suppressor genes, oncogenes and DNA repair genes. Main focus was given to multiple critical signaling cross-talking pathways including transforming growth factor β (TGFβ) signaling pathways that are directly linked to CRC. In conclusion, we recommend further analysis in order to experimentally confirm exact relationships between selected differentially expressed miRNAs and their predicted target genes and downstream functional consequences.

The role of inflammatory miRNA-mRNA interactions in PBMCs of colorectal cancer and obesity patients

Introduction

Inflammation is a critical hallmark in obesity and colorectal cancer (CRC). This study aimed to investigate effective microRNA (miRNA)–messenger RNA (mRNA) interactions on inflammatory networks involved in obesity and CRC.

Methods

The literature searches were applied to identify genes expression reported on peripheral blood mononuclear cells (PBMCs) and/or blood of CRC subjects and to find inflammatory miRNA  in blood samples. Furthermore, bioinformatics analysis was utilized to find inflammatory miRNA:mRNA interactions of the genes. Finally, a case‐control study was set to investigate the expression of LAMC1 and GNB3 genes besides miR‐10b, miR‐506‐3p, miR‐150‐5p, and miR‐124‐3p in CRC and control subjects.

Results

The expression of LAMC1 gene in healthy control groups was associated with body mass index (BMI) (p < .05). The level of miR‐10b (p < .001), miR‐506 (p < .001), and miR‐124 (p <. 001) were significantly increased in PBMCs of CRC patients, while they were not associated with BMI. The level of miR‐150 was associated with BMI in healthy subjects (p < .05).

Conclusions

The changes in the level of miR‐506 and miR‐124 in CRC patients may be associated with the regulatory role of these miRNAs on LAMC1 expression. The LAMC1 may be related to BMI, however, more observational studies on other populations are needed.

MicroRNA regulation of the proliferation and apoptosis of Leydig cells in diabetes

BACKGROUND

The number of patients with diabetes is increasing worldwide. Diabetic testicular damage can cause spermiogenesis disorders and sexual dysfunction. We thus explored the role of miRNAs in diabetic testicular damage, and revealed that they could serve as effective prevention and treatment therapeutic targets.

METHODS

Streptozotocin (STZ) was used to generate a rat model of type 2 diabetes. Rat testicular tissues were used for miRNA and mRNA sequencing. Through bioinformatics analysis, we constructed an miRNA-mRNA diabetic testicular damage regulatory network and screened for key miRNAs. We also used Leydig cells to generate a diabetic cell model and detected the downstream target genes of miRNAs, secretion of testosterone, and proliferation and apoptotic levels to elucidate the role and mechanism of the selected miRNAs in diabetic testicular damage.

RESULTS

Using second-generation sequencing, we identified 19 differentially expressed miRNAs and 555 mRNAs in the testes of diabetic rats. Based on computational prediction of targets and negative regulation relationships, we constructed a miRNA-mRNA regulatory network, including 12 miRNAs and 215 mRNAs. KEGG enrichment analysis revealed that genes were more concentrated on the survival signalling pathway. Based on this, we screened 2 key miRNAs, miR-504 and miR-935. In vitro, glucose could induce an increase in miR-504 and miR-935, whereas a decrease in MEK5 and MEF2C in a dose-dependent manner. Overexpression of miR-504 and miR-935 led to the decreased expression of MEK5 and MEF2C, decreased proliferation rate of Leydig cells, increased apoptotic rate, and decreased secretion of testosterone. Whereas, knockdown of miR-504 and miR-935 displayed opposite tendencies.

CONCLUSIONS

miRNAs play important roles in diabetic testicular damage. miR-504 and miR-935 might regulate testicular damage through the classic survival pathway of MEK5-ERK5-MEF2C. Targeted inhibition of miR-504 and miR-935 could reverse the high-glucose-induced testicular complications, thus posing as a potential therapeutic approach in diabetic testicular injury.

An in silico approach to identify and prioritize miRNAs target sites polymorphisms in colorectal cancer and obesity

Colorectal cancer (CRC) and obesity are linked clinical entities with a series of complex processes being engaged in their development. MicroRNAs (miRNAs) participate in these processes through regulating CRC and obesity‐related genes. This study aimed to develop an in silico approach to systematically identify and prioritize miRNAs target sites polymorphisms in obesity and CRC. Data from genome‐wide association studies (GWASs) were used to retrieve CRC and obesity‐associated variants. The polymorphisms that were resided in experimentally verified or computationally predicted miRNA target sites were retrieved and prioritized using a range of bioinformatics analyses. We found 6284 CRC and 38931 obesity unique variants. For CRC 33 haplotypes variants in 134 interactions were in miRNA targetome, while for obesity we found more than 935 unique interactions. Functionally prioritized SNPs revealed that, SNPs in 153 obesity and 50 CRC unique interactions were have disruptive effects on miRNA:mRNA integration by changing on target RNA secondary structure. Structural accessibility of target sites were decreased in 418 and 103 unique interactions and increased in 516 and 79 interactions, for obesity and CRC, respectively. The miRNA:mRNA hybrid stability was increased in 127 and 17 unique interactions and decreased in 33 and 24 interactions for the effect of obesity and CRC SNPs, respectively. In this study, seven SNPs with 15 interactions and three SNPs with four interactions were prioritized for obesity and CRC, respectively. These SNPs could be used for future studies for finding potential biomarkers for diagnoses, prognosis, or treatment of CRC and obesity.

Long non-coding RNA MIAT promotes the growth of melanoma via targeting miR-150

Melanoma is a common skin cancer and it can lead to high mortality probably by early invasion and metastasis. LncRNA MIAT is involved in tumor proliferation, invasion and epithelial-to-mesenchymal transition (EMT). However, the roles of MIAT in melanoma still require further investigation. Thus, the aim of the study is to investigate the roles of MIAT in melanoma, especially the effects of MIAT on EMT of melanoma cancer cells. The results showed that the expression of MIAT was significantly upregulated in melanoma tissue and cells compared with the normal skin and normal melanocytes; moreover, miR-150 was confirmed as a target of MIAT. Furthermore, knockdown of MIAT inhibited cell proliferation and invasion in melanoma cancer cells and transfection of miR-150 inhibitors partial abrogated the anti-tumor effects of MIAT siRNA. In addition, MIAT siRNA also inhibited the EMT of melanoma cells, while miR-150 inhibitors can reverse the effects of MIAT siRNA. Finally, knockdown of MIAT also inhibited the carcinogenic effects of melanoma in vivo by targeting miR-150. In conclusion, we reported that MIAT promotes the proliferation, invasion and EMT of melanoma cells via targeting miR-150, which suggested that MIAT might be a therapeutic target for the treatment of melanoma.