miR‑675 promotes colorectal cancer cell growth dependent on tumor suppressor DMTF1

miRNAs as Interconnectors between Obesity and Cancer

Obesity and cancer are a concern of global interest. It is proven that obesity may trigger the development or progression of some types of cancer; however, the connection by non-coding RNAs has not been totally explored. In the present review, we discuss miRNAs and lncRNAs dysregulation involved in obesity and some cancers, shedding light on how these conditions may exacerbate one another through the dysregulation of ncRNAs. lncRNAs have been reported as regulating microRNAs. An in silico investigation of lncRNA and miRNA interplay is presented. Our investigation revealed 44 upregulated and 49 downregulated lncRNAs in obesity and cancer, respectively. miR-375, miR-494-3p, miR-1908, and miR-196 were found interacting with 1, 4, 4 and 4 lncRNAs, respectively, which are involved in PPARγ cell signaling regulation. Additionally, miR-130 was found to be downregulated in obesity and reported as modulating 5 lncRNAs controlling PPARγ cell signaling. Similarly, miR-128-3p and miR-143 were found to be downregulated in obesity and cancer, interacting with 5 and 4 lncRNAs, respectively, associated with MAPK cell signaling modulation. The delicate balance between miRNA and lncRNA expression emerges as a critical determinant in the development of obesity-associated cancers, presenting these molecules as promising biomarkers. However, additional and deeper studies are needed to reach solid conclusions about obesity and cancer connection by ncRNAs.

Diagnostic and Prognostic Significance of miR-675-3p in Patients With Atherosclerosis

In recent years, a rising number of studies have confirmed that microRNA (miRNA) plays a prominent role in the early diagnosis and prognostic value assessment of cardiovascular diseases. The current study was conducted to examine the expression of miR-675-3p in atherosclerosis (AS) patients and to evaluate its clinical diagnosis and prognostic value. 110 AS patients and 70 healthy controls were included in the study. Serum miR-675-3p levels were detected by quantitative real-time PCR (qRT-PCR). The clinical diagnostic significance of serum miR-675-3p in AS patients were investigated by the receiver operating characteristic (ROC) curve. The correlation between miRNA and carotid intima-media thickness (CIMT) was analyzed by the Spearman correlation coefficient. The prognostic significance of serum miR-675-3p was evaluated by the Kaplan-Meier method and Cox regression analysis. The patient’s serum miR-675-3p was significantly increased than the healthy individuals (P < 0.05). An increase of carotid intima-media thickness (CIMT) was positively correlated with the promotion of serum miR-675-3p levels. The area under the ROC curve (AUC) was 0.918, with high sensitivity and specificity. miR-675-3p is a key independent predictor of cardiovascular adverse events in AS patients (HR = 5.375, 95%CI = 1.590-18.170, P = 0.007), and patients with elevated miR-675-3p were more likely to have cardiovascular adverse events (log-rank P = 0.030). Increased miR-675-3p can be used as a potential marker for the diagnosis of AS, and was associated with the poor prognosis of AS.

miRNAs Involved in Esophageal Carcinogenesis and miRNA-Related Therapeutic Perspectives in Esophageal Carcinoma

MicroRNAs (miRNAs) are small non-coding RNAs that play a pivotal role in many aspects of cell biology, including cancer development. Within esophageal cancer, miRNAs have been proved to be involved in all phases of carcinogenesis, from initiation to metastatic spread. Several miRNAs have been found to be dysregulated in esophageal premalignant lesions, namely Barrett’s esophagus, Barrett’s dysplasia, and squamous dysplasia. Furthermore, numerous studies have investigated the alteration in the expression levels of many oncomiRNAs and tumor suppressor miRNAs in esophageal squamous cell carcinoma and esophageal adenocarcinoma, thus proving how miRNAs are able modulate crucial regulatory pathways of cancer development. Considering these findings, miRNAs may have a role not only as a diagnostic and prognostic tool, but also as predictive biomarker of response to anti-cancer therapies and as potential therapeutic targets. This review aims to summarize several studies on the matter, focusing on the possible diagnostic–therapeutic implications.

MiR-6838-5p facilitates the proliferation and invasion of renal cell carcinoma cells through inhibiting the DMTF1/ARF-p53 axis

Renal cell carcinoma (RCC) is one of the most common renal malignancies in the urinary system. Numerous studies have demonstrated that miRNAs can regulate tumorigenesis and progression. This study aims to investigate the role and regulatory mechanism of miR-6838-5p in RCC. Our study confirmed that miR-6838-5p was upregulated in human RCC tissues (30/42, 77.43%, P < 0.01) and RCC cell lines (P < 0.05) compared to adjacent non-neoplastic tissues and normal renal epithelial cells. In vitro, overexpression of miR-6838-5p enhanced cell proliferation and invasion in human RCC cell lines (ACHN and 786-O), which were detected by CCK-8, Transwell and Colony formation assays (P < 0.05), and knockdown of miR-6838-5p suppressed cell proliferation and invasion (P < 0.05). Results of Bioinformatics analysis combined with Dual-luciferase reporter gene assay demonstrated that miR-6838-5p could bind to Cyclin D binding myb-like transcription factor 1 (DMTF1). In addition, RT-qPCR and Western blotting confirmed that DMTF1 was downregulated in RCC tissues and cell lines. Meanwhile, it was demonstrated that overexpression of miR-6838-5p inhibited DMTF1 level in ACHN cells. Next, we confirmed that DMTF1 overexpression reversed the inhibitory effects of overexpression of miR-6838-5p on phosphatase and tensin homolog (PTEN), tumor protein 53(p53), murine double minute 2 (MDM2) and alternative reading frame (ARF) protein levels in the ARF-p53 signaling pathway. In conclusion, our research showed that miR-6838-5p enhanced the proliferation and invasion of RCC cells by inhibiting the DMTF1/ARF-p53 axis.

Comprehensive upstream and downstream regulatory analyses identify miR-675-3p as a potential prognostic biomarker in melanoma

This study assessed miR-675-3p-related regulatory mechanisms in melanoma and the clinical relevance of such regulatory activities. We downloaded miRNA mature strand expression RNA-Seq, phenotypic, and DNA methylation data pertaining to the TCGA Melanoma cohort. Differentially expressed miRNAs (DEMs) between metastatic and primary melanoma patient tissues were then identified, and miR-675-3p expression in melanoma patient peripheral blood was confirmed using the GSE20994 GEO dataset, while its expression in melanoma cell lines was evaluated via qRT-RCR. The clinical and prognostic implications of miR-675-3p in melanoma were assessed, and miR-675-3p target genes were identified using bioinformatics tools. Functional roles of this miRNA were explored via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. We identified 3 and 22 miRNAs that were up- and downregulated, respectively, in metastatic melanoma samples relative to primary melanoma samples. Upregulation of miR-675-3p was associated with poorer overall patient survival, tumor histologic grade, and Clark's level. Consistently, miR-675-3p was also overexpressed in the peripheral blood of melanoma patients relative to healthy controls, and in melanoma cell lines relative to control cells. Gene regulatory networks indicated that 32 transcription factors control miR-675-3p expression, and that it, in turn, regulates 10 target genes. KEGG analyses indicated that these genes were associated with cell cycle, transcriptional misregulation in cancer, TGF-beta signaling, and HIF-1 signaling pathways. Gain-of-function assays revealed that miR-675-3p could promote cell proliferation via accelerating cell cycle progression. Western blotting results indicated that miR-675-3p could active TGF-beta and HIF-1 signaling. Through upstream and downstream analyses of miR-675-3p-related regulatory activity, we confirmed that this miRNA participates in key melanoma-related processes and offers value as a prognostic biomarker in melanoma patients.

Mechanisms regulating DMTF1β/γ expression and their functional interplay with DMTF1α

The cyclin D binding myb-like transcription factor 1 (DMTF1), a haplo-insufficient tumor suppressor gene, has 3 alternatively spliced mRNA isoforms encoding DMTF1α, β and γ proteins. Previous studies have indicated a tumor suppressive role of DMTF1α and the oncogenic activity of DMTF1β, while the function of DMTF1γ remains largely undetermined. In the present study, the mechanisms regulating DMTF1 isoform expression were investigated and the functional interplay of DMTF1β and γ with DMTF1α was characterized. It was found that specific regions of DMTF1β and γ transcripts can impair their mRNA integrity or stability, and thus reduce protein expression levels. Additionally, DMTF1β and γ proteins exhibited a reduced stability compared to DMTF1α and all 3 DMTF1 isoforms were localized in the nuclei. Two basic residues, K52 and R53, in the DMTF1 isoforms determined their nuclear localization. Importantly, both DMTF1β and γ could associate with DMTF1α and antagonize its transactivation of the ARF promoter. Consistently, the ratios of both DMTF1β/α and γ/α were significantly associated with a poor prognoses of breast cancer patients, suggesting oncogenic roles of DMTF1β and γ isoforms in breast cancer development.

Long noncoding RNA HULC accelerates the growth of human liver cancer stem cells by upregulating CyclinD1 through miR675-PKM2 pathway via autophagy

BACKGROUND

The functions of HULC have been demonstrated in several cancers. However, its mechanism has not been elucidated in human liver cancer stem cells.

METHODS

Liver cancer stem cells were isolated from Huh7 cells; gene infection and tumorigenesis test in vitro and in vivo were performed.

RESULTS

We demonstrate that HULC promotes growth of liver cancer stem cells in vitro and in vivo. Mechanistically, HULC enhances the expression of Sirt1 dependent on miR675 and then induces the cellular autophagy through Sirt1. HULC enhances CyclinD1 and thereby increases pRB and inhibited P21 WAF1/CIP 1 via autophagy-miR675-PKM2 pathway in human liver cancer stem cells. Ultimately, our results demonstrate that CyclinD1 is required for the oncogenic functions of HULC in liver cancer stem cells.

CONCLUSIONS

It reveals the key molecular signaling pathways for HULC and provides important basic information for finding effective tumor therapeutic targets based on HULC.

The Neglected Insulin: IGF-II, a Metabolic Regulator with Implications for Diabetes, Obesity, and Cancer

When originally discovered, one of the initial observations was that, when all of the insulin peptide was depleted from serum, the vast majority of the insulin activity remained and this was due to a single additional peptide, IGF-II. The IGF-II gene is adjacent to the insulin gene, which is a result of gene duplication, but has evolved to be considerably more complicated. It was one of the first genes recognised to be imprinted and expressed in a parent-of-origin specific manner. The gene codes for IGF-II mRNA, but, in addition, also codes for antisense RNA, long non-coding RNA, and several micro RNA. Recent evidence suggests that each of these have important independent roles in metabolic regulation. It has also become clear that an alternatively spliced form of the insulin receptor may be the principle IGF-II receptor. These recent discoveries have important implications for metabolic disorders and also for cancer, for which there is renewed acknowledgement of the importance of metabolic reprogramming.

MicroRNA‑203a‑3p is a candidate tumor suppressor that targets thrombospondin 2 in colorectal carcinoma

The aim of the present study was to investigate the role of miR-203a-3p in colorectal cancer (CRC) and identify the target gene of microRNA (miR)-203a-3p. A total of 59 sets of cancer tissues and corresponding adjacent non-tumor tissues were collected from CRC patients (aged 31–78 years) between October 2016 and May 2017. Total RNA extraction and reverse transcription-quantitative polymerase chain reaction analysis, transfection assay, and Transwell and apoptosis assays, western blot analysis, a luciferase reporter assay and immunohistochemistry were performed. miR-203a-3p was found to be significantly downregulated in CRC tissues compared with adjacent normal tissues. The overexpression of miR-203a-3p was shown to inhibit the invasion and migration of human CRC SW480 and HT29 cells, and increase their apoptosis rates. Furthermore, miR-203a-3p downregulated the expression of thrombospondin 2 (THBS2) in SW480 and HT29 cells. It was also experimentally demonstrated that miR-203a-3p binds to the 3′-untranslated region of THBS2, downregulating THBS2 expression and thereby inhibiting CRC progression and metastasis. The expression of miR-203a-3p, which serves a tumor-suppressive role, in CRC tissues was significantly downregulated. As miR-203a-3p was determined to target THBS2 to inhibit CRC progression and metastasis; thus, miR-203a-3p may be considered as a potential novel approach to treating CRC.