Elevated microRNA-185 is associated with high vascular endothelial growth factor receptor 2 expression levels and high microvessel density in clear cell renal cell carcinoma

MicroRNA-185-5p: a marker of brain-sparing in foetuses with late-onset growth restriction

To compare the expression of microRNA-185-5p (miR-185-5p) in normal foetuses and in foetuses with late-onset growth restriction (FGR) and to determine the factors influencing this expression. In a prospective study, 40 foetuses (22 of them with late-onset FGR and 18 with normal growth) were scanned with Doppler ultrasound after week 35 and followed until birth. Subsequently, blood samples from umbilical cords were collected after delivery to evaluate the expression of miR-185-5p using real-time qPCR. Finally, multivariable regression analysis was applied to determine the clinical and ultrasonographic factors influencing miR-185-5p expression in both normal and late-onset FGR foetuses. In comparison with normal foetuses, late-onset FGR foetuses expressed upregulation of miR-185-5p (2.26 ± 1.30 versus 1.27 ± 1.03 2^-ddCt, P = 0.011). Multivariable regression analysis confirmed that cerebroplacental ratio (P < 0.05) was the only determinant of this overexpression. FGR foetuses overexpress miR-185-5p in relation to brain-sparing. Future studies will be needed to investigate the role of miR-185 in the management of late-onset FGR.

MiRNAs in renal cell carcinoma

MicroRNAs (miRNAs) are small RNA sequences that act as post-transcriptional regulatory genes to control many cellular processes through pairing bases with a complementary messenger RNA (mRNA). A single miRNA molecule can regulate more than 200 different transcripts and the same mRNA can be regulated by multiple miRNAs. In this review, we highlight the importance of miRNAs and collect the existing evidence on their relationship with kidney cancer.

MicroRNAs Targeting HIF-2α, VEGFR1 and/or VEGFR2 as Potential Predictive Biomarkers for VEGFR Tyrosine Kinase and HIF-2α Inhibitors in Metastatic Clear-Cell Renal Cell Carcinoma

Metastatic clear-cell renal cell carcinoma (m-ccRCC) is characterized by increased hypoxia-induced factor (HIF)-2α and vascular endothelial growth factor receptor (VEGFR)-dependent angiogenesis through loss of function of the von Hippel-Lindau protein. VEGFR tyrosine kinase inhibitors (VEGFR-TKIs) are a cornerstone of m-ccRCC treatment, and new treatments targeting HIF-2α are currently under investigation. However, predictive biomarkers for these treatments are lacking. In this retrospective cohort study including 109 patients treated with VEGFR-targeted therapies as first-line treatment, we aimed to study the possible predictive function of microRNAs (miRNAs) targeting HIF-2α, VEGFR1 and VEGFR2. We selected miRNAs inversely correlated with HIF-2α, VEGFR1 and/or VEGFR2 expression and with predicted target sites in the respective genes and subsequently studied their impact on therapeutic outcomes. We identified four miRNAs (miR-34c-5p, miR-221-3p, miR-222-3p and miR-3529-3p) inversely correlated with VEGFR1 and/or VEGFR2 expression and associated with tumor shrinkage and progression-free survival (PFS) upon treatment with VEGFR-TKIs, highlighting the potential predictive value of these miRNAs. Moreover, we identified three miRNAs (miR-185-5p, miR-223-3p and miR-3529-3p) inversely correlated with HIF-2α expression and associated with tumor shrinkage and PFS upon treatment with VEGFR-TKIs. These three miRNAs can have a predictive value not only upon treatment with VEGFR-TKIs but possibly also upon treatment with the upcoming HIF-2α inhibitor belzutifan.

Identification of biomarkers and construction of a microRNA‑mRNA regulatory network for clear cell renal cell carcinoma using integrated bioinformatics analysis

With the recent research development, the importance of microRNAs (miRNAs) in renal clear cell carcinoma (CCRCC) has become widely known. The purpose of this study is to screen out the potential biomarkers of renal clear cell carcinoma (CCRCC) by microarray analysis. The miRNA chip (GSE16441) and mRNA chip (GSE66270) related to CCRCC were downloaded from the Gene Expression Omnibus (GEO) database. After data filtering and pretreating, R platform and a series of analysis tools (funrich3.1.3, string, Cytoscape_ 3.2.1, David, etc.) were used to analyze chip data and identify the specific and highly sensitive biomarkers. Finally, by constructing the miRNA -mRNA interaction network, it was determined that five miRNAs (hsa-mir-199a-5p, hsa-mir-199b-5p, hsa-mir-532-3p and hsa-mir-429) and two key genes (ETS1 and hapln1) are significantly related to the overall survival rate of patients.

miRNA profiling in renal carcinoma suggest the existence of a group of pro-angionenic tumors in localized clear cell renal carcinoma

Renal cell carcinoma comprises a variety of entities, the most common being the clear-cell, papillary and chromophobe subtypes. These subtypes are related to different clinical evolution; however, most therapies have been developed for clear-cell carcinoma and there is not a specific treatment based on different subtypes. In this study, one hundred and sixty-four paraffin samples from primary nephrectomies for localized tumors were analyzed. MiRNAs were isolated and measured by microRNA arrays. Significance Analysis of Microarrays and Consensus Cluster algorithm were used to characterize different renal subtypes. The analyses showed that chromophobe renal tumors are a homogeneous group characterized by an overexpression of miR 1229, miR 10a, miR 182, miR 1208, miR 222, miR 221, miR 891b, miR 629-5p and miR 221-5p. On the other hand, clear cell renal carcinomas presented two different groups inside this histological subtype, with differences in miRNAs that regulate focal adhesion, transcription, apoptosis and angiogenesis processes. Specifically, one of the defined groups had an overexpression of proangiogenic microRNAs miR185, miR126 and miR130a. In conclusion, differences in miRNA expression profiles between histological renal subtypes were established. In addition, clear cell renal carcinomas had different expression of proangiogenic miRNAs. With the emergence of antiangiogenic drugs, these differences could be used as therapeutic targets in the future or as a selection method for tailoring personalized treatments.

The biological roles and clinical implications of microRNAs in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) accounts for about 3% of tumors in adults as well as 85% of all primary renal carcinoma. And it is the third most predominant urological carcinoma, but it has the maximum mortality rate. Early diagnosis and proper follow-up of ccRCC patients may improve the prognosis of the illness. Thus, it is imperative to understand the new biomarkers of ccRCC and study new method for the modern therapy of this deadly disease. Furthermore, a large number of microRNAs (miRNAs), small non-coding RNAs, have been relevant to tumor type, stage, or survival and miRNAs might be progressed as the markers of diagnosis or prognosis in ccRCC. A growing body of data also advised the rationality of regarding miRNAs as therapeutic targets for ccRCC treatment. In this review, we tried to summarize biogenesis of miRNAs and their expression profiles, biological roles, and clinical implications in ccRCC.

Expression of micro-RNAs and genes related to angiogenesis in ccRCC and associations with tumor characteristics

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the third most common urological cancer in adults. Our aim is to evaluate genes and miRNAs expression profiles involved with angiogenesis and tumor characteristics in ccRCC.

METHODS

The expression levels of miRNAs miR-99a, 99b, 100; 199a; 106a; 106b; 29a; 29b; 29c; 126; 200a, 200b and their respective target genes: mTOR, HIF1-α, VHL, PDGF, VEGF, VEGFR1 and VEGFR2 were analyzed using qRT-PCR in tumor tissue samples from 56 patients with ccRCC. Five samples of benign renal tissue were utilized as control. The expression levels of miRNAs and genes were related to tumor size, Fuhrman nuclear grade and microvascular invasion.

RESULTS

miR99a was overexpressed in most samples and its target gene mTOR was underexpressed, this also occurs for miRNAs 106a, 106b, and their target gene VHL. An increase in miR-200b was correlated with high-risk tumors (p = 0.01) while miR-126 overexpression was associated with Fuhrman's low grade (p = 0.03).

CONCLUSIONS

Our results show that in ccRCC there are changes in miRNAs expression affecting gene expression that could be important in determining the aggressiveness of this lethal neoplasia.

Candesartan attenuates angiogenesis in hepatocellular carcinoma via downregulating AT1R/VEGF pathway

Angiotensin II type 1 receptor (AT1R) was reported to express in many types of tumors, promoting tumor growth and angiogenesis. We herein examined AT1R expression in liver cancer and the potential antitumor effects of AT1R antagonist Candesartan in liver cancer. We found that AT1R expression was positively correlated with VEGF-A expression and microvascular density (MVD) in 40 HCC patients. Angiotensin II and Candesartan neither had effects on the proliferation of liver cancer cells in vitro. However, Angiotensin II upregulated AT1R protein expression and promoted production of VEGF-A in liver cancer cells in a dose-dependent manner. Candesartan was able to reverse this process in a dose-dependent manner. Moreover, Candesartan downregulated the expression of VEGF-A in SMMC-7721 bearing xenografts in mice and inhibited tumor growth and angiogenesis in vivo. Our data suggested that AT1R antagonist Candesartan might be useful to suppress liver cancer by inhibiting angiogenesis.

miR-372 suppresses tumour proliferation and invasion by targeting IGF2BP1 in renal cell carcinoma

OBJECTIVES

MicroRNAs (miRNAs) are endogenous small non-coding RNAs that regulate proteins and mRNAs for degradation or translational suppression. Up to now, the role of miR-372 in renal cell carcinoma has remained unknown; in this study, we have aimed to reveal its functional importance in this tumour.

MATERIALS AND METHODS

qRT-PCR was performed to measure expression levels of miR-372 in renal cell carcinoma cell lines and tissues. CCK-8 and an invasion assay were performed to measure its functional role. Luciferase assays, qRT-PCR and western blotting were performed to discover miR-372's target gene.

RESULTS

We demonstrated that miRNA-372 was down-regulated in renal cell carcinoma cell lines and tissue specimens; its over-expression inhibited cell proliferation and invasion. Moreover, we showed that miRNA-372 repressed insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) expression by directly interacting with its putative binding site at the 3'-UTR. Furthermore, ectopic expression of IGF2BP1 significantly reversed suppression of cell proliferation and invasion caused by miR-372 over-expression.

CONCLUSIONS

Our data indicated that miR-372 seemed to function as a tumour suppressor in renal cell carcinoma progression by inhibiting the IGF2BP1 expression.