microRNA-210-3p depletion by CRISPR/Cas9 promoted tumorigenesis through revival of TWIST1 in renal cell carcinoma

MiRNA Signatures Related to Invasiveness and Recurrence in Patients With Non-Functioning Pituitary Neuroendocrine Tumors

PURPOSE

This preliminary study aimed to analyze and identify differentially expressed miRNAs in Bulgarian patients with non-functioning pituitary neuroendocrine tumors (NFPitNET). The relationship between deregulated miRNAs and tumor invasiveness, recurrence, and size was determined.

METHODS

Twenty patients with NFPitNET were selected and fresh pituitary tumor tissues were collected. RNA containing miRNAs were isolated using miRNAeasy mini kit and analyzed by quantitative real-time polymerase chain reaction (PCR) using LNA miRNA Cancer-Focus PCR Panel (Qiagen).

RESULTS

Three miRNAs (miR-210-3p, miR-149-3p, and miR-29b-3p) were deregulated in invasive compared to non-invasive NFPitNETs. Differential expression of four-miRNA signatures - miRNA-17, miR-19, miR-106a, and miR-20, correlated with patient recurrence.

CONCLUSION

This prospective pilot study selected a unique miRNA expression profile, that correlates with invasiveness and recurrence in non-functioning pituitary neuroendocrine tumors. Moreover, some of the selected miRNAs are reported for the first time in patients with this disease, shedding light on the molecular mechanisms involved in pituitary pathogenesis. The identified miRNAs demonstrate potential as biomarkers, deserving further investigation in a larger cohort to validate their clinical applicability.

Targeted disruption of the BCR-ABL fusion gene by Cas9/dual-sgRNA inhibits proliferation and induces apoptosis in chronic myeloid leukemia cells

The BCR-ABL fusion gene, formed by the fusion of the breakpoint cluster region protein ( BCR) and the Abl Oncogene 1, Receptor Tyrosine Kinase ( ABL) genes, encodes the BCR-ABL oncoprotein, which plays a crucial role in leukemogenesis. Current therapies have limited efficacy in patients with chronic myeloid leukemia (CML) because of drug resistance or disease relapse. Identification of novel strategies to treat CML is essential. This study aims to explore the efficiency of novel CRISPR-associated protein 9 (Cas9)/dual-single guide RNA (sgRNA)-mediated disruption of the BCR-ABL fusion gene by targeting BCR and cABL introns. A co-expression vector for Cas9 green fluorescent protein (GFP)/dual-BA-sgRNA targeting BCR and cABL introns is constructed to produce lentivirus to affect BCR-ABL expression in CML cells. The effects of dual-sgRNA virus-mediated disruption of BCR-ABL are analyzed via the use of a genomic sequence and at the protein expression level. Cell proliferation, cell clonogenic ability, and cell apoptosis are assessed after dual sgRNA virus infection, and phosphorylated BCR-ABL and its downstream signaling molecules are detected. These effects are further confirmed in a CML mouse model via tail vein injection of Cas9-GFP/dual-BA-sgRNA virus-infected cells and in primary cells isolated from patients with CML. Cas9-GFP/dual-BA-sgRNA efficiently disrupts BCR-ABL at the genomic sequence and gene expression levels in leukemia cells, leading to blockade of the BCR-ABL tyrosine kinase signaling pathway and disruption of its downstream molecules, followed by cell proliferation inhibition and cell apoptosis induction. This method prolongs the lifespan of CML model mice. Furthermore, the effect is confirmed in primary cells derived from patients with CML.

Diagnostic applications and therapeutic option of Cascade CRISPR/Cas in the modulation of miRNA in diverse cancers: promises and obstacles

The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas technology is a molecular tool specific to sequences for engineering genomes. Among diverse clusters of Cas proteins, the class 2/type II CRISPR/Cas9 system, despite several challenges, such as off-target effects, editing efficiency, and efficient delivery, has shown great promise for driver gene mutation discovery, high-throughput gene screening, epigenetic modulation, nucleic acid detection, disease modeling, and more importantly for therapeutic purposes. CRISPR-based clinical and experimental methods have applications across a wide range of areas, especially for cancer research and, possibly, anticancer therapy. On the other hand, given the influential role of microRNAs (miRNAs) in the regulations of cellular division, carcinogenicity, tumorigenesis, migration/invasion, and angiogenesis in diverse normal and pathogenic cellular processes, in different stages of cancer, miRNAs are either oncogenes or tumor suppressors, according to what type of cancer they are involved in. Hence, these noncoding RNA molecules are conceivable biomarkers for diagnosis and therapeutic targets. Moreover, they are suggested to be adequate predictors for cancer prediction. Conclusive evidence proves that CRISPR/Cas system can be applied to target small non-coding RNAs. However, the majority of studies have highlighted the application of the CRISPR/Cas system for targeting protein-coding regions. In this review, we specifically discuss diverse applications of CRISPR-based tools for probing miRNA gene function and miRNA-based therapeutic involvement in different types of cancers.

Novel insights regarding the role of noncoding RNAs in diabetes

Diabetes mellitus (DM) is a group of metabolic disorders defined by hyperglycemia induced by insulin resistance, inadequate insulin secretion, or excessive glucagon secretion. In 2021, the global prevalence of diabetes is anticipated to be 10.7% (537 million people). Noncoding RNAs (ncRNAs) appear to have an important role in the initiation and progression of DM, according to a growing body of research. The two major groups of ncRNAs implicated in diabetic disorders are miRNAs and long noncoding RNAs. miRNAs are single-stranded, short (17–25 nucleotides), ncRNAs that influence gene expression at the post-transcriptional level. Because DM has reached epidemic proportions worldwide, it appears that novel diagnostic and therapeutic strategies are required to identify and treat complications associated with these diseases efficiently. miRNAs are gaining attention as biomarkers for DM diagnosis and potential treatment due to their function in maintaining physiological homeostasis via gene expression regulation. In this review, we address the issue of the gradually expanding global prevalence of DM by presenting a complete and up-to-date synopsis of various regulatory miRNAs involved in these disorders. We hope this review will spark discussion about ncRNAs as prognostic biomarkers and therapeutic tools for DM. We examine and synthesize recent research that used novel, high-throughput technologies to uncover ncRNAs involved in DM, necessitating a systematic approach to examining and summarizing their roles and possible diagnostic and therapeutic uses.

Disruption in networking of KCMF1 linked ubiquitin ligase impairs autophagy in CD8+ memory T cells of patients with renal cell carcinoma

Metastatic Renal Cell Carcinoma (mRCC) remains incurable, despite the current checkpoint-blockade-driven, limited overall response rate. The CD8⁺ memory T cells can mount a rapid and an effective response. The ubiquitin ligase RAD6-KCMF1-UBR4-mediated regulation of autophagy in CD8⁺ memory T cells in patients with renal cell carcinoma (RCC) remains unexplored. Consequently, flow cytometry was used to study memory T cells, and their subsets, including activation and regulatory phenotypes in peripheral blood mononuclear cells (PBMCs). Expression of the ubiquitin ligase and autophagy was measured both at the cellular and molecular levels in memory T cells of patients with RCC. JC.1 staining and Annexin/PI assays were used to evaluate the memory T cells depolarization and apoptosis rates. The results indicated that the disruption of Ub-E2-E3 complex and impaired autophagy in memory T cells diminished their ability to survive and combat against tumor cells. Inhibition of memory T cells apoptosis by targeting E3 ubiquitin ligase or autophagy pathways can be explored as a potential therapeutic strategy to improve the long-term survival of memory T cells in RCC.

MicroRNA Expression Signatures in Clear Cell Renal Cell Carcinoma: High-Throughput Searching for Key miRNA Markers in Patients from the Volga-Ural Region of Eurasian Continent

Clear cell renal cell carcinoma (ccRCC) is characterized by high molecular genetic heterogeneity, metastatic activity and unfavorable prognosis. MicroRNAs (miRNA) are 22-nucleotide noncoding RNAs that are aberrantly expressed in cancer cells and have gained serious consideration as non-invasive cancer biomarkers. We investigated possible differential miRNA signatures that may differentiate high-grade ccRCC from primary disease stages. High-throughput miRNAs expression profiling, using TaqMan OpenArray Human MicroRNA panel, was performed in a group of 21 ccRCC patients. The obtained data was validated in 47 ccRCC patients. We identified nine dysregulated miRNAs (miRNA-210, -642, -18a, -483-5p, -455-3p, -487b, -582-3p, -199b and -200c) in tumor ccRCC tissue compared to normal renal parenchyma. Our results show that the combination of miRNA-210, miRNA-483-5p, miRNA-455 and miRNA-200c is able to distinguish low and high TNM ccRCC stages. Additionally, miRNA-18a, -210, -483-5p and -642 showed statistically significant differences between the low stage tumor ccRCC tissue and normal renal tissue. Contrariwise, the high stages of the tumor process were accompanied by alteration in the expression levels of miRNA-200c, -455-3p and -582-3p. Although the biological roles of these miRNAs in ccRCC are not totally clear, our findings need additional investigations into their involvement in the pathogenesis of ccRCC. Prospective studies with large study cohorts of ccRCC patients are important to further establish the clinical validity of our miRNA markers to predict ccRCC.

Application of CRISPR/Cas9 Technology in Cancer Treatment: A Future Direction

Gene editing, especially with clustered regularly interspaced short palindromic repeats associated protein 9 (CRISPR-Cas9), has advanced gene function science. Gene editing's rapid advancement has increased its medical/clinical value. Due to its great specificity and efficiency, CRISPR/Cas9 can accurately and swiftly screen the whole genome. This simplifies disease-specific gene therapy. To study tumor origins, development, and metastasis, CRISPR/Cas9 can change genomes. In recent years, tumor treatment research has increasingly employed this method. CRISPR/Cas9 can treat cancer by removing genes or correcting mutations. Numerous preliminary tumor treatment studies have been conducted in relevant fields. CRISPR/Cas9 may treat gene-level tumors. CRISPR/Cas9-based personalized and targeted medicines may shape tumor treatment. This review examines CRISPR/Cas9 for tumor therapy research, which will be helpful in providing references for future studies on the pathogenesis of malignancy and its treatment.

Diabetic cardiomyopathy: The role of microRNAs and long non-coding RNAs

Diabetes mellitus (DM) is on the rise, necessitating the development of novel therapeutic and preventive strategies to mitigate the disease's debilitating effects. Diabetic cardiomyopathy (DCMP) is among the leading causes of morbidity and mortality in diabetic patients globally. DCMP manifests as cardiomyocyte hypertrophy, apoptosis, and myocardial interstitial fibrosis before progressing to heart failure. Evidence suggests that non-coding RNAs, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), regulate diabetic cardiomyopathy-related processes such as insulin resistance, cardiomyocyte apoptosis and inflammation, emphasizing their heart-protective effects. This paper reviewed the literature data from animal and human studies on the non-trivial roles of miRNAs and lncRNAs in the context of DCMP in diabetes and demonstrated their future potential in DCMP treatment in diabetic patients.

CRISPR-Cas knockout of miR21 reduces glioma growth

Non-coding RNAs, including microRNAs (miRNAs), support the progression of glioma. miR-21 is a small, non-coding transcript involved in regulating gene expression in multiple cellular pathways, including the regulation of proliferation. High expression of miR-21 has been shown to be a major driver of glioma growth. Manipulating the expression of miRNAs is a novel strategy in the development of therapeutics in cancer. In this study we aimed to target miR-21. Using CRISPR genome-editing technology, we disrupted the miR-21 coding sequences in glioma cells. Depletion of this miRNA resulted in the upregulation of many downstream miR-21 target mRNAs involved in proliferation. Phenotypically, CRISPR-edited glioma cells showed reduced migration, invasion, and proliferation in vitro. In immunocompetent mouse models, miR-21 knockout tumors showed reduced growth resulting in an increased overall survival. In summary, we show that by knocking out a key miRNA in glioma, these cells have decreased proliferation capacity both in vitro and in vivo. Overall, we identified miR-21 as a potential target for CRISPR-based therapeutics in glioma.

miRNA Pattern in Hypoxic Microenvironment of Kidney Cancer—Role of PTEN

MicroRNAs are post-transcriptional regulators of gene expression, and disturbances of their expression are the basis of many pathological states, including cancers. The miRNA pattern in the context of tumor microenvironment explains mechanisms related to cancer progression and provides a potential target of modern therapies. Here we show the miRNA pattern in renal cancer focusing on hypoxia as a characteristic feature of the tumor microenvironment and dysregulation of PTEN, being a major tumor suppressor. Methods comprised the CRSPR/Cas9 mediated PTEN knockout in the Renca kidney cancer cell line and global miRNA expression analysis in both in vivo and in vitro (in normoxic and hypoxic conditions). The results were validated on human cancer models with distinct PTEN status. The increase in miR-210-3p in hypoxia was universal; however, the hypoxia-induced decrease in PTEN was associated with an increase in miR-221-3p, the loss of PTEN affected the response to hypoxia differently by decreasing miR-10b-5p and increasing miR-206-3p. In turn, the complete loss of PTEN induces miR-155-5p, miR-100-5p. Upregulation of miR-342-3p in knockout PTEN occurred in the context of the whole tumor microenvironment. Thus, effective identification of miRNA patterns in cancers must consider the specificity of the tumor microenvironment together with the mutations of key suppressors.

Elucidating miRNA Function in Cancer Biology via the Molecular Genetics’ Toolbox

Micro-RNA (miRNAs) are short non-coding RNAs of about 18–20 nucleotides in length and are implicated in many cellular processes including proliferation, development, differentiation, apoptosis and cell signaling. Furthermore, it is well known that miRNA expression is frequently dysregulated in many cancers. Therefore, this review will highlight the various mechanisms by which microRNAs are dysregulated in cancer. Further highlights include the abundance of molecular genetics tools that are currently available to study miRNA function as well as their advantages and disadvantages with a special focus on various CRISPR/Cas systems This review provides general workflows and some practical considerations when studying miRNA function thus enabling researchers to make informed decisions in regards to the appropriate molecular genetics tool to be utilized for their experiments.

The Role of MiRNA in Cancer: Pathogenesis, Diagnosis, and Treatment

Cancer is also determined by the alterations of oncogenes and tumor suppressor genes. These gene expressions can be regulated by microRNAs (miRNA). At this point, researchers focus on addressing two main questions: "How are oncogenes and/or tumor suppressor genes regulated by miRNAs?" and "Which other mechanisms in cancer cells are regulated by miRNAs?" In this work we focus on gathering the publications answering these questions. The expression of miRNAs is affected by amplification, deletion or mutation. These processes are controlled by oncogenes and tumor suppressor genes, which regulate different mechanisms of cancer initiation and progression including cell proliferation, cell growth, apoptosis, DNA repair, invasion, angiogenesis, metastasis, drug resistance, metabolic regulation, and immune response regulation in cancer cells. In addition, profiling of miRNA is an important step in developing a new therapeutic approach for cancer.

Knockdown of microRNA-214-3p Promotes Tumor Growth and Epithelial-Mesenchymal Transition in Prostate Cancer

Simple Summary

Prostate Cancer is the second leading cause of cancer-related deaths in the United States. In this study, we analyzed a molecule known as a microRNA, which regulates the expression of genes. microRNAs are involved in processes related to cancer onset and progression. Abnormal expression of microRNAs can promote prostate cancer. This study showed that knockdown of microRNA miR-214-3p enhanced the progression and of prostate cancer. In addition, miR-214 regulated the expression of many genes. These results are useful to better understand the function of miR-214-3p in prostate cancer and can be a useful target in the treatment of the disease.

Abstract

Abnormal expression of microRNA miR-214-3p (miR-214) is associated with multiple cancers. In this study, we assessed the effects of CRISPR/Cas9 mediated miR-214 depletion in prostate cancer (PCa) cells and the underlying mechanisms. Knockdown of miR-214 promoted PCa cell proliferation, invasion, migration, epithelial-mesenchymal transition (EMT), and increased resistance to anoikis, a key feature of PCa cells that undergo metastasis. The reintroduction of miR-214 in miR-214 knockdown cells reversed these effects and significantly suppressed cell proliferation, migration, and invasion. These in vitro studies are consistent with the role of miR-214 as a tumor suppressor. Moreover, miR-214 knockout increased tumor growth in PCa xenografts in nude mice supporting its anti-oncogenic role in PCa. Knockdown of miR-214 increased the expression of its target protein, Protein Tyrosine Kinase 6 (PTK6), a kinase shown to promote oncogenic signaling and tumorigenesis in PCa. In addition, miR-214 modulated EMT as exhibited by differential regulation of E-Cadherin, N-Cadherin, and Vimentin both in vitro and in vivo. RNA-seq analysis of miR-214 knockdown cells revealed altered gene expression related to PCa tumor growth pathways, including EMT and metastasis. Collectively, our findings reveal that miR-214 is a key regulator of PCa oncogenesis and is a potential novel therapeutic target for the treatment of the disease.

MicroRNA Therapeutics in Cancer: Current Advances and Challenges

Simple Summary

Cancer is a complex disease associated with deregulation of numerous genes. In addition, redundant cellular pathways limit efficiency of monotarget drugs in cancer therapy. MicroRNAs are a class of gene expression regulators, which often function by targeting multiple genes. This feature makes them a double-edged sword (a) as attractive targets for anti-tumor therapy and concomitantly (b) as risky targets due to their potential side effects on healthy tissues. As for conventional antitumor drugs, nanocarriers have been developed to circumvent the problems associated with miRNA delivery to tumors. In this review, we highlight studies that have established the pre-clinical proof-of concept of miRNAs as relevant therapeutic targets in oncology. Particular attention was brought to new strategies based on nanovectorization of miRNAs as well as to the perspectives for their applications.

Abstract

The discovery of microRNAs (miRNAs) in 1993 has challenged the dogma of gene expression regulation. MiRNAs affect most of cellular processes from metabolism, through cell proliferation and differentiation, to cell death. In cancer, deregulated miRNA expression leads to tumor development and progression by promoting acquisition of cancer hallmark traits. The multi-target action of miRNAs, which enable regulation of entire signaling networks, makes them attractive tools for the development of anti-cancer therapies. Hence, supplementing downregulated miRNA by synthetic oligonucleotides or silencing overexpressed miRNAs through artificial antagonists became a common strategy in cancer research. However, the ultimate success of miRNA therapeutics will depend on solving pharmacokinetic and targeted delivery issues. The development of a number of nanocarrier-based platforms holds significant promises to enhance the cell specific controlled delivery and safety profile of miRNA-based therapies. In this review, we provide among the most comprehensive assessments to date of promising nanomedicine platforms that have been tested preclinically, pertaining to the treatment of selected solid tumors including lung, liver, breast, and glioblastoma tumors as well as endocrine malignancies. The future challenges and potential applications in clinical oncology are discussed.

microRNA-210/ Long non-coding RNA MEG3 axis inhibits trophoblast cell migration and invasion by suppressing EMT process

INTRODUCTION

Pre-eclampsia is characterized by insufficient spiral artery remodeling, and trophoblast dysfunction plays an important role in this process. Noncoding RNAs (microRNAs (miRNAs) and long noncoding RNAs (LncRNAs) are included) can regulate trophoblasts. MicroRNA-210 (miR-210) can decrease trophoblast cell migration and invasion and may act as a biomarker for preeclampsia. LncRNA maternally expressed gene 3 (MEG3) plays a positive role in pre-eclampsia, and MEG3 can be a downstream target of miR-210 in human umbilical vein endothelial cells (HUVEC). However, the effect of miR-210 on MEG3 and the mechanism of action of the miR-210/MEG3 axis in trophoblasts remain unclear.

METHOD

The localization of miR-210 and MEG3 in the human placenta in early pregnancy was determined by in situ hybridization. Then, HTR8/SVneo cells were used to investigated the effect of miR-210 on MEG3 expression and biological activity of trophoblasts in the migration and invasion assays. Gain- and loss-of-function experiments were performed to determine the mechanism of action of miR-210 and MEG3 in Epithelial-mesenchymal transition (EMT) of HTR8/SVneo cells.

RESULTS

The qRT-PCR and western blotting results demonstrated that the upregulation of miR-210 decreases MEG3, N-cadherin and Vimentin expression and increases E-cadherin expression to inhibit EMT in HTR-8/SVneo cells. Inhibition of the expression of miR-210 results in the opposite effects. Gain- and loss-of-function assay indicated that miR-210 can impair the EMT, migration, and invasion of HTR8/SVneo cells by regulating the expression of MEG3.

DISSCUSSION

MiR-210 may be a negative regulator of trophoblast EMT that acts by suppressing MEG3 expression.

The interplay between non-coding RNAs and Twist1 signaling contribute to human disorders

Twist-related protein 1 (Twist1) is a basic helix-loop-helix (bHLH) transcription factor (TF) being coded by the TWIST1 gene. This TF has a fundamental effect on the normal development and in the pathogenesis of various diseases especially cancer. Twist1 has interactions with some long non-coding RNAs and miRNAs. The interactions between this TF and various miRNAs such as miR-16, miR-26b-5p, miR-1271, miR-539, miR-214, miR-200b/c, miR-335, miR-10b, and miR-381 are implicated in the carcinogenic processes. TP73-AS1, LINC01638, ATB, NONHSAT101069, CASC15, H19, PVT1, LINC00339, LINC01385, TANAR, SNHG5, DANCR, CHRF, and TUG1 are among long non-coding RNAs which interact with Twist1 and participate in the carcinogenesis. This review aims at depicting the interaction between these non-coding transcripts and Twist1 and the consequence of these interactions in human neoplasms.

CRISPR-Cas9, A Promising Therapeutic Tool for Cancer Therapy: A Review

Cancer is one of the most leading causes of mortality all over the world and remains a foremost social and economic burden. Mutations in the genome of individuals are taking place more frequently due to the excessive progress of xenobiotics and industrialization in the present world. With the progress in the field of molecular biology, it is possible to alter the genome and to observe the functional changes derived from genetic modulation using gene-editing technologies. Several therapies have been applied for the treatment of malignancy which affect the normal body cells; however, more effort is required to develop vsome latest therapeutic approaches for cancer biology and oncology exploiting these molecular biology advances. Recently, the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) associated protein 9 (Cas9) system has emerged as a powerful technology for cancer therapy because of its great accuracy and efficiency. Genome editing technologies have demonstrated a plethora of benefits to the biological sciences. CRISPR- Cas9, a versatile gene editing tool, has become a robust strategy for making alterations to the genome of organisms and a potent weapon in the arsenal of tumor treatment. It has revealed an excellent clinical potential for cancer therapy by discovering novel targets and has provided the researchers with the perception about how tumors respond to drug therapy. Stern efforts are in progress to enhance its efficiency of sequence specific targeting and consequently repressing offtarget effects. CRISPR-Cas9 uses specific proteins to convalesce mutations at genetic level. In CRISPR-Cas9 system, RNA-guided Cas9 endonuclease harnesses gene mutation, DNA deletion or insertion, transcriptional activation or repression, multiplex targeting only by manipulating 20-nucleotide components of RNA. Originally, CRISPR-Cas9 system was used by bacteria for their defense against different bacteriophages, and recently this system is receiving noteworthy appreciation due to its emerging role in the treatment of genetic disorders and carcinogenesis. CRISPR-Cas9 can be employed to promptly engineer oncolytic viruses and immune cells for cancer therapeutic applications. More notably, it has the ability to precisely edit genes not only in model organisms but also in human being that permits its use in therapeutic analysis. It also plays a significant role in the development of complete genomic libraries for cancer patients. In this review, we have highlighted the involvement of CRISPR-Cas9 system in cancer therapy accompanied by its prospective applications in various types of malignancy and cancer biology. In addition, some other conspicuous functions of this unique system have also been discussed beyond genome editing.

Early prognostic performance of miR155-5p monitoring for the risk of rejection: Logistic regression with a population pharmacokinetic approach in adult kidney transplant patients

Previous results from our group and others have shown that urinary pellet expression of miR155-5p and urinary CXCL-10 production could play a key role in the prognosis and diagnosis of acute rejection (AR) in kidney transplantation patients. Here, a logistic regression model was developed using NONMEM to quantify the relationships of miR155-5p urinary expression, CXCL-10 urinary concentration and tacrolimus and mycophenolic acid (MPA) exposure with the probability of AR in adult kidney transplant patients during the early post-transplant period. Owing to the contribution of therapeutic drug monitoring to achieving target exposure, neither tacrolimus nor MPA cumulative exposure was identified as a predictor of AR in the studied population. Even though CXCL-10 urinary concentration showed a trend, its effect on AR was not significant. In contrast, urinary miR155-5p expression was prognostic of clinical outcome. Monitoring miR155-5p urinary pellet expression together with immunosuppressive drug exposure could be very useful during routine clinical practice to identify patients with a potential high risk of rejection at the early stages of the post-transplant period. This early risk assessment would allow for the optimization of treatment and improved prevention of AR.

MicroRNA Signature in Renal Cell Carcinoma

Renal cell carcinoma (RCC) includes 2.2% of all diagnosed cancers and 1.8% of cancer-related mortalities. The available biomarkers or screening methods for RCC suffer from lack of sensitivity or high cost, necessitating identification of novel biomarkers that facilitate early diagnosis of this cancer especially in the susceptible individuals. MicroRNAs (miRNAs) have several advantageous properties that potentiate them as biomarkers for cancer detection. Expression profile of miRNAs has been assessed in biological samples from RCC patients. Circulatory or urinary levels of certain miRNAs have been proposed as markers for RCC diagnosis or follow-up. Moreover, expression profile of some miRNAs has been correlated with response to chemotherapy, immunotherapy or targeted therapeutic options such as sunitinib. In the current study, we summarize the results of studies that assessed the application of miRNAs as biomarkers, therapeutic targets or modulators of response to treatment modalities in RCC patients.

Targeting NPL4 via drug repositioning using disulfiram for the treatment of clear cell renal cell carcinoma

The alcohol-abuse drug disulfiram has antitumor effects against diverse cancer types via inhibition of the ubiquitin-proteasome protein nuclear protein localization protein 4 (NPL4). However, the antitumor effects of NPL4 and disulfiram in clear cell renal cell carcinoma (ccRCC) are unclear. Here, we evaluated the therapeutic potential of targeting the ubiquitin-proteasome pathway using disulfiram and RNA interference and investigated the mechanisms underlying disulfiram in ccRCC. According to data from The Cancer Genome Atlas, NPL4 mRNA expression was significantly upregulated in clinical ccRCC samples compared with that in normal kidney samples, and patients with high NPL4 expression had poor overall survival compared with patients with low NPL4 expression. Disulfiram and NPL4 siRNA inhibited ccRCC cell proliferation in vitro, and disulfiram inhibited ccRCC tumor growth in a xenograft model. Synergistic antiproliferative effects were observed for combination treatment with disulfiram and sunitinib in vitro and in vivo. In RCC cells from mice treated with disulfiram and/or sunitinib, several genes associated with serine biosynthesis and aldose reductase were downregulated in cells treated with disulfiram or sunitinib alone and further downregulated in cells treated with both disulfiram and sunitinib. These findings provided insights into the mechanisms of disulfiram and suggested novel therapeutic strategies for RCC treatment.

EMT signaling: potential contribution of CRISPR/Cas gene editing

Epithelial to mesenchymal transition (EMT) is a complex plastic and reversible cellular process that has critical roles in diverse physiological and pathological phenomena. EMT is involved in embryonic development, organogenesis and tissue repair, as well as in fibrosis, cancer metastasis and drug resistance. In recent years, the ability to edit the genome using the clustered regularly interspaced palindromic repeats (CRISPR) and associated protein (Cas) system has greatly contributed to identify or validate critical genes in pathway signaling. This review delineates the complex EMT networks and discusses recent studies that have used CRISPR/Cas technology to further advance our understanding of the EMT process.

Characterization of PHGDH expression in bladder cancer: potential targeting therapy with gemcitabine/cisplatin and the contribution of promoter DNA hypomethylation

d‐3‐Phosphoglycerate dehydrogenase (PHGDH) conducts an important step in the synthesis of serine. Importantly, the PHGDH gene is often amplified in certain cancers. Our previous studies revealed that PHGDH gene amplification was associated with poor overall survival in clear cell renal cell carcinoma (ccRCC) and that metabolic reprogramming of serine synthesis through PHGDH recruitment allowed ccRCC cells to survive in unfavorable environments. There have been no investigations of the role of PHGDH expression in bladder cancer (BC). In this investigation, we examined the clinical importance of PHDGH in BC. Furthermore, we asked whether PHGDH expression could be exploited for BC therapy. Finally, we investigated the regulatory mechanisms that modulated the expression of PHGDH. Using data from The Cancer Genome Atlas, we found that patients with high‐grade BC had significantly higher PHGDH expression levels than did those with low‐grade BC. In addition, patients with high PHGDH expression did not survive as long as those with low expression. PHGDH downregulation by si‐RNAs or an inhibitor in BC cell lines significantly inhibited proliferative ability and induced apoptosis. Furthermore, combined treatment using a PHGDH inhibitor and gemcitabine/cisplatin achieved synergistic tumor suppression compared to use of a single agent both in vitro as well as in vivo. Mechanistic analyses of PHGDH regulation showed that PHGDH expression might be associated with DNA copy number and hypomethylation in BC. These findings suggest novel therapeutic strategies could be used in BC. Finally, our data enhance our understanding of the role of PHGDH in BC.

Non-coding RNAs in cancer: platforms and strategies for investigating the genomic "dark matter"

The discovery of the role of non-coding RNAs (ncRNAs) in the onset and progression of malignancies is a promising frontier of cancer genetics. It is clear that ncRNAs are candidates for therapeutic intervention, since they may act as biomarkers or key regulators of cancer gene network. Recently, profiling and sequencing of ncRNAs disclosed deep deregulation in human cancers mostly due to aberrant mechanisms of ncRNAs biogenesis, such as amplification, deletion, abnormal epigenetic or transcriptional regulation. Although dysregulated ncRNAs may promote hallmarks of cancer as oncogenes or antagonize them as tumor suppressors, the mechanisms behind these events remain to be clarified. The development of new bioinformatic tools as well as novel molecular technologies is a challenging opportunity to disclose the role of the "dark matter" of the genome. In this review, we focus on currently available platforms, computational analyses and experimental strategies to investigate ncRNAs in cancer. We highlight the differences among experimental approaches aimed to dissect miRNAs and lncRNAs, which are the most studied ncRNAs. These two classes indeed need different investigation taking into account their intrinsic characteristics, such as length, structures and also the interacting molecules. Finally, we discuss the relevance of ncRNAs in clinical practice by considering promises and challenges behind the bench to bedside translation.

Role of microRNA-210-3p in hepatitis B virus-related hepatocellular carcinoma

Hepatitis B virus (HBV)-related hepatocarcinogenesis is not necessarily associated with the liver fibrotic stage and is occasionally seen at early fibrotic stages. MicroRNAs (miRNAs) are essentially 18- to 22-nucleotide-long endogenous noncoding RNAs. Aberrant miRNA expression is a common feature of various human cancers. The aberrant expression of specific miRNAs has been shown in hepatocellular carcinoma (HCC) tissue compared with nontumor tissue. Thus, we examined targetable miRNAs as a potential new biomarker related to the high risk of HBV-related hepatocarcinogenesis, toward the prevention of cancer-related deaths. HCC tissue samples from 29 patients who underwent hepatectomy at our hospital in 2002-2013 were obtained. We extracted the total RNA and analyzed it by microRNA array, real-time RT-PCR, and three comparisons: 1) HBV-related HCC and adjacent nontumor tissue, 2) HCV-related HCC and adjacent nontumor tissue, and 3) non-HBV-, non-HCV-related HCC and adjacent nontumor tissue. We also performed a functional analysis of miRNAs specific for HBV-related HCC by using HBV-positive HCC cell lines. MiR-210-3p expression was significantly increased only in the HBV-related HCC tissue samples. MiR-210-3p expression was upregulated, and the levels of its target genes were reduced in the HBV-positive HCC cells. The inhibition of miR-210-3p enhanced its target gene expression in the HBV-positive HCC cells. In addition, miR-210-3p regulated the HBx expression in HBV-infected Huh7/NTCP cells. The enhanced expression of miR-210-3p was detected specifically in HBV-related HCC and regulated various target genes, including HBx in the HBV-positive HCC cells. MiR-210-3p might, thus, be a new biomarker for the risk of HBV-related HCC.NEW & NOTEWORTHY Our present study demonstrated that miR-210-3p is the only microRNA with enhanced expression in HBV-related HCC, and the enhanced expression of miR-210-3p upregulates HBx expression. Therefore, miR-210-3p might be a pivotal biomarker of HBV-related hepatocarcinogenesis, and the inhibition of miR-210-3p could prevent inducing hepatocarcinogenesis related to HBV infection.

Precision gene editing technology and applications in nephrology

The expanding field of precision gene editing is empowering researchers to directly modify DNA. Gene editing is made possible using synonymous technologies: a DNA-binding platform to molecularly locate user-selected genomic sequences and an associated biochemical activity that serves as a functional editor. The advent of accessible DNA-targeting molecular systems, such as zinc-finger nucleases, transcription activator-like effectors (TALEs) and CRISPR-Cas9 gene editing systems, has unlocked the ability to target nearly any DNA sequence with nucleotide-level precision. Progress has also been made in harnessing endogenous DNA repair machineries, such as non-homologous end joining, homology-directed repair and microhomology-mediated end joining, to functionally manipulate genetic sequences. As understanding of how DNA damage results in deletions, insertions and modifications increases, the genome becomes more predictably mutable. DNA-binding platforms such as TALEs and CRISPR can also be used to make locus-specific epigenetic changes and to transcriptionally enhance or suppress genes. Although many challenges remain, the application of precision gene editing technology in the field of nephrology has enabled the generation of new animal models of disease as well as advances in the development of novel therapeutic approaches such as gene therapy and xenotransplantation.

miR-210-3p regulates the proliferation and apoptosis of non-small cell lung cancer cells by targeting SIN3A

Previous studies have indicated that microRNA (miR)-210-3p is upregulated in NSCLC, however, the specific mechanism underlying the role of miR-210-3p in NSCLC pathogenesis requires further investigation. The aim of the present study was to explore the roles of miR-210-3p in NSCLC and the associated mechanisms. A total of 30 NSCLC tissues and paired adjacent normal tissues were collected for study. Reverse transcription-quantitative polymerase chain reaction was performed to compare the expression of miR-210-3p in the 30 paired cancerous and adjacent normal tissues. Additionally, the expression of miR-210-3p in different NSCLC lines and normal human lung epithelial cell line BEAS-2B were also compared. Furthermore, A549 and H1299 NSCLC cells were cultured and transfected with miR-210-3p inhibitors, and MTT and propidium iodide/annexin V assays were performed to investigate the effects of miR-210-3p inhibition on the proliferation and apoptosis of the cells. RT-qPCR and western blot analyses were also performed to determine the effects of miR-210-3p on the expression levels of SIN3A, B-cell lymphoma 2 (Bcl-2) and Caspase-3. Finally, a reverse experiment was conducted by transfecting A549 cells with miR-210-3p inhibitor and SIN3A small interfering (si)RNA, and a dual-luciferase reporter assay was performed to confirm that SIN3A is a direct target of miR-210-3p. It was observed that miR-210-3p was significantly upregulated in NSCLC tissues compared with the levels in the adjacent normal tissues, and that the expression of miR-210-3p in patients with NSCLC was negatively correlated with the expression of SIN3A in NSCLC tissue. miR-210-3p was also significantly upregulated in different NSCLC cell lines compared with the levels in BEAS-2B cells. The transient downregulation of miR-210-3p in A549 cells led to a significant suppression of cell proliferation and markedly increased cell apoptosis, as well as increased the expression of SIN3A and Caspase-3 and decreased the expression of Bcl-2. On the other hand, co-transfection of miR-210-3p inhibitor and SIN3A siRNA partially blocked miR-210-3p inhibitor-induced pro-apoptotic effects. The results of the dual-luciferase reporter assay demonstrated that SIN3A is a direct target of miR-210-3p. Collectively, these findings indicate that can regulate the proliferation and apoptosis of NSCLC cells by targeting SIN3A. These results suggest that miR-210-3p has the potential to become a novel therapeutic target for the treatment of NSCLC.

Molecular Mechanisms in Clear Cell Renal Cell Carcinoma: Role of miRNAs and Hypermethylated miRNA Genes in Crucial Oncogenic Pathways and Processes

Clear cell renal cell carcinoma (ccRCC) is the third most common urological cancer, and it has the highest mortality rate. The increasing drug resistance of metastatic ccRCC has resulted in the search for new biomarkers. Epigenetic regulatory mechanisms, such as genome-wide DNA methylation and inhibition of protein translation by interaction of microRNA (miRNA) with its target messenger RNA (mRNA), are deeply involved in the pathogenesis of human cancers, including ccRCC, and may be used in its diagnosis and prognosis. Here, we review oncogenic and oncosuppressive miRNAs, their putative target genes, and the crucial pathways they are involved in. The contradictory behavior of a number of miRNAs, such as suppressive and anti-metastatic miRNAs with oncogenic potential (for example, miR-99a, miR-106a, miR-125b, miR-144, miR-203, miR-378), is examined. miRNAs that contribute mostly to important pathways and processes in ccRCC, for instance, PI3K/AKT/mTOR, Wnt-β, histone modification, and chromatin remodeling, are discussed in detail. We also separately consider their participation in crucial oncogenic processes, such as hypoxia and angiogenesis, metastasis, and epithelial-mesenchymal transition (EMT). The review also considers the interactions of long non-coding RNAs (lncRNAs) and miRNAs of significance in ccRCC. Recent advances in the understanding of the role of hypermethylated miRNA genes in ccRCC and their usefulness as biomarkers are reviewed based on our own data and those available in the literature. Finally, new data and perspectives concerning the clinical applications of miRNAs in the diagnosis, prognosis, and treatment of ccRCC are discussed.

miR‑210‑3p regulates cell growth and affects cisplatin sensitivity in human ovarian cancer cells via targeting E2F3

The potential role of microRNA (miR)‑210‑3p in carcinogenesis and the cisplatin sensitivity of ovarian cancer were evaluated in the present study. The relative expression levels of miR‑210‑3p in cisplatin‑sensitive SKOV‑3 cells and cisplatin‑resistant SKOV‑3/DDP cells were determined using reverse transcription‑quantitative polymerase chain reaction analysis. miR‑210‑3p mimics and inhibitors were transfected into SKOV‑3/DDP cells. Cell Counting Kit‑8, scratch and Transwell invasion assays and flow cytometry were conducted to evaluate the role of miR‑210‑3p in ovarian cancer cells. A luciferase reporter assay was used to verify the association between miR‑210‑3p and E2F transcription factor 3 (E2F3). Drug sensitivity was evaluated by treating the cells with cisplatin. The expression level of miR‑210‑3p was lower in SKOV‑3/DDP cells than in SKOV‑3 cells. Compared with the untransfected control, SKOV‑3 cells transfected with miR‑210‑3p exhibited a significantly higher survival rate. The overexpression of miR‑210‑3p inhibited SKOV‑3/DDP cell proliferation, migration and invasion, and promoted cell apoptosis. By contrast, the inhibition of miR‑210‑3p promoted cell migration and invasion. The luciferase reporter assay confirmed that E2F3 was a direct target gene of miR‑210‑3p. Cisplatin treatment resulted in a sharp decrease in the survival rate of SKOV‑3/DDP cells transfected with the miR‑210‑3p mimics. The decrease in cell survival rate caused by the overexpression of miR‑210‑3p was rescued by the overexpression of E2F3 in SKOV‑3/DDP cells. Taken together, these results suggest that miR‑210‑3p may act as a tumor suppressor in ovarian cancer cells and affect the sensitivity of cells to cisplatin by directly targeting E2F3. This indicates its potential use as a therapeutic target for improving drug resistance in ovarian cancer.

Downregulation of RGMA by HIF-1A/miR-210-3p axis promotes cell proliferation in oral squamous cell carcinoma

Repulsive guidance molecules comprise a group of proteins that play an important role in carcinogenesis through interactions with their receptors, but their function in oral squamous cell carcinoma (OSCC) is unclear. Here, we investigated the potential role of the RGM family members in oral cancer pathogenesis. Our study showed that only RGMA was significantly downregulated in the OSCC tissues analyzed by TCGA and validated this finding in OSCC cells. The decreased expression of RGMA was strongly associated with the T stage and with poor prognosis. The ectopic expression of RGMA significantly inhibited the proliferation of OSCC cells both in vitro and in vivo. Moreover, we confirmed that RGMA was a target of miR-210-3p in OSCC and miR-210-3p overexpression contributed to the acceleration of OSCC growth. Further experiments revealed that HIF1A specifically interacted with the promoter of miR-210-3p and enhanced its expression. In summary, our research indicates that RGMA is regulated by the HIF1A/miR-210-3p axis and inhibits OSCC cell proliferation; thus, in the future, the development of therapies that target the HIF1A/miR-210-3p/RGMA axis may aid in the treatment of aggressive cancers.

MicroRNA-885-5p promotes osteosarcoma proliferation and migration by downregulation of cell division cycle protein 73 homolog expression

Osteosarcoma (OS) is the most common primary malignant bone tumor. Numerous studies have strongly implicated the ectopic expression of microRNAs (miRNAs/miRs), including miR-885-5p, which is aberrantly expressed in several cancer types, in multiple cancer-related processes. However, the role of miR-885-5p in OS remains unknown. In the present study, it was found that the expression of miR-885-5p was markedly upregulated in OS cell lines and clinical tissues. Moreover, high expression of miR-885-5p was significantly associated with the development of OS. The human OS MG-63 cell line was transfected with recombinant lentivirus to regulate miR-885-5p expression. Overexpressed miR-885-5p significantly promoted the proliferation and migration of MG-63 cells in vitro, while downregulating miR-885-5p expression reversed these effects. Furthermore, bioinformatic analysis was used to predict the potential target genes of miR-885-5p, and cell division cycle protein 73 homolog (CDC73) was identified as a novel and direct target of miR-885-5p. This interaction was further confirmed using reverse transcription-quantitative polymerase chain reaction, western blotting and luciferase activity assays. These findings suggest that miR-885-5p serves a critical role in facilitating OS proliferation and migration, and can regulate CDC73 expression in OS cells and tissues. Thus, miR-885-5p could be a promising novel therapeutic biomarker for OS.

Lamp2 inhibits epithelial-mesenchymal transition by suppressing Snail expression in HCC

Lysosomal associated membrane protein 2 (Lamp2) influences a broad range of physiological and pathological processes. However, little is known about the role of Lamp2 in hepatocellular carcinoma (HCC) metastasis. This study found that Lamp2 expression was significantly lower in HCC tissues than in adjacent nontumor tissues (ANTs), and its expression level correlated with HCC metastasis. Low Lamp2 expression was significantly correlated with the AFP serum level (> 20 ng/Ml, P = 0.024), capsular formation (absent, P = 0.024), and microvascular invasion (present, P < 0.001), and low expression of Lamp2 indicated a poor prognosis in HCC. LowLamp2 expression was an independent and significant risk factor for recurrence-free survival (RFS; P < 0.001) and overall survival (OS; P < 0.001) in HCC. In this study, we demonstrated that Lamp2 overexpression inhibited cell motility and invasiveness in vitro and inhibited lung metastasis in vivo. In addition, Lamp2 could reverse the EMT program. Lamp2 silencing by siRNA in HCC cell lines enhanced the expression of mesenchymal markers and decreased the expression of epithelial markers. Consistent with these findings, Lamp2 overexpression had the opposite effects. Mechanistically, we found that Lamp2 could suppress Snail expression, upregulate E-cadherin, and inhibit HCC cell epithelial-mesenchymal transition (EMT).Together, these findings suggest that Lamp2 attenuates EMT by suppressing Snail expression in HCC.

Bromodomain protein BRD4 inhibitor JQ1 regulates potential prognostic molecules in advanced renal cell carcinoma

Sunitinib is a standard molecular-targeted drug used as a first-line treatment for metastatic clear cell renal cell carcinoma (ccRCC); however, resistance to sunitinib has become a major problem in medical practice. Recently, bromodomain containing 4 (BRD4), a member of the bromodomain family proteins, was identified as a promising therapeutic target, and its inhibitor JQ1 has been shown to have inhibitory effects in various human cancers. However, the anti-cancer effects of JQ1 in ccRCC, particularly sunitinib-resistant ccRCC, are still unclear. Here, we aimed to elucidate the anti-cancer effects of JQ1 and the mechanisms underlying BRD4 inhibition in sunitinib-sensitive and -resistant ccRCCs. Analysis of The Cancer Genome Atlas (TCGA) ccRCC cohort showed that patients with high BRD4 expression had shorter overall survival than those with low expression. JQ1 treatment significantly inhibited tumor growth of sunitinib-sensitive and -resistant ccRCC cells in part through MYC regulation. Based on RNA sequencing analyses of ccRCC cells treated with JQ1 to elucidate the mechanisms other than MYC regulation, we identified several oncogenes that may be potential therapeutic targets or prognostic markers; patients with high expression of SCG5, SPOCD1, RGS19, and ARHGAP22 had poorer overall survival than those with low expression in TCGA ccRCC cohort. Chromatin immunoprecipitation assays revealed that these oncogenes may be promising BRD4 targets, particularly in sunitinib-resistant ccRCC cells. These results identified SCG5, SPOCD1, RGS19, and ARHGAP22 as potential prognostic markers and showed that BRD4 inhibition may have applications as a potential therapeutic approach in sunitinib-sensitive and -resistant ccRCC.

Expanding the Utilization of Formalin-Fixed, Paraffin-Embedded Archives: Feasibility of miR-Seq for Disease Exploration and Biomarker Development from Biopsies with Clear Cell Renal Cell Carcinoma

Novel predictive tools for clear cell renal cell carcinoma (ccRCC) are urgently needed. MicroRNAs (miRNAs) have been increasingly investigated for their predictive value, and formalin-fixed paraffin-embedded biopsy archives may potentially be a valuable source of miRNA sequencing material, as they remain an underused resource. Core biopsies of both cancerous and adjacent normal tissues were obtained from patients (n = 12) undergoing nephrectomy. After small RNA-seq, several analyses were performed, including classifier evaluation, obesity-related inquiries, survival analysis using publicly available datasets, comparisons to the current literature and ingenuity pathway analyses. In a comparison of tumour vs. normal, 182 miRNAs were found with significant differential expression; miR-155 was of particular interest as it classified all ccRCC samples correctly and correlated well with tumour size (R² = 0.83); miR-155 also predicted poor survival with hazard ratios of 2.58 and 1.81 in two different TCGA (The Cancer Genome Atlas) datasets in a univariate model. However, in a multivariate Cox regression analysis including age, sex, cancer stage and histological grade, miR-155 was not a statistically significant survival predictor. In conclusion, formalin-fixed paraffin-embedded biopsy tissues are a viable source of miRNA-sequencing material. Our results further support a role for miR-155 as a promising cancer classifier and potentially as a therapeutic target in ccRCC that merits further investigation.

MicroRNA-139-3p Suppresses Tumor Growth and Metastasis in Hepatocellular Carcinoma by Repressing ANXA2R

The direct roles of miR-139-3p on hepatocellular carcinoma (HCC) cell growth and metastasis remain poorly understood. We attempted to demonstrate the regulatory role of miR-139-3p in HCC progression and its underlying mechanisms. Here we showed that miR-139-3p expression was significantly reduced in the HCC tissues compared to paratumor tissues. Exogenous overexpression of miR-139-3p inhibited the migration and invasion of HCC cells, whereas downregulation of miR-139-3p was able to induce HCC HepG2 and SNU-449 cell migration and invasion. In addition, miR-139-3p inhibited HCC growth and lung metastasis in an in vivo mouse model, which is mainly regulated by annexin A2 receptor (ANXA2R). Finally, we identified that the expression of miR-139-3p was inversely correlated with ANXA2R expression in human HCC tissue. All these results demonstrated that miR-139-3p inhibited the metastasis process in HCC by downregulating ANXA2R expression.

Down-regulation of miR-210-3p encourages chemotherapy resistance of renal cell carcinoma via modulating ABCC1

Background

ATP-binding cassette transporter super-family including ABCC1 and MDR-1 were involved in multi-drug resistance (MDR) of renal cell carcinoma (RCC) patients. Several miRNAs were confirmed to promote the MDR and the survival of tumor cells.

Methods

The RCC cell lines Caki-2 with vinblastine-resistant (Caki-2/VBL) or doxorubicin-resistant (Caki-2/DOX) were constructed, respectively. The expressions of miR-210-3p, ABCC1 and MDR-1 protein were determined by qRT-PCR and Western blot assays. The viability of RCC cells was assessed by MTT assay. The regulatory relationship between miR-210-3p and ABCC1 was analyzed by Dual Luciferase assay. The effect of miR-210-3p in vivo was investigated with a tumor xenograft model in mice.

Results

MiR-210-3p expression was observed to significantly decrease in Caki-2/VBL and Caki-2/DOX cells. Meanwhile, ABCC1 and MDR-1 were significantly increased in Caki-2/VBL and Caki-2/DOX cells. ABCC1 was a novel target of miR-210-3p and negatively regulated by miR-210-3p. And miR-210-3p improved drug-sensitivity of RCC cells. Down-regulation of ABCC1 could reverse the effect of miR-210-3p knockdown on the drug-resistance and the level of MDR-1 in drug-sensitive RCC cells.

Conclusion

We confirmed that down-regulation of miR-210-3p increased ABCC1 expression, thereby enhancing the MRP-1-mediated multidrug resistance of RCC cells.

CRISPR-Cas9: a promising genetic engineering approach in cancer research

Bacteria and archaea possess adaptive immunity against foreign genetic materials through clustered regularly interspaced short palindromic repeat (CRISPR) systems. The discovery of this intriguing bacterial system heralded a revolutionary change in the field of medical science. The CRISPR and CRISPR-associated protein 9 (Cas9) based molecular mechanism has been applied to genome editing. This CRISPR-Cas9 technique is now able to mediate precise genetic corrections or disruptions in in vitro and in vivo environments. The accuracy and versatility of CRISPR-Cas have been capitalized upon in biological and medical research and bring new hope to cancer research. Cancer involves complex alterations and multiple mutations, translocations and chromosomal losses and gains. The ability to identify and correct such mutations is an important goal in cancer treatment. In the context of this complex cancer genomic landscape, there is a need for a simple and flexible genetic tool that can easily identify functional cancer driver genes within a comparatively short time. The CRISPR-Cas system shows promising potential for modeling, repairing and correcting genetic events in different types of cancer. This article reviews the concept of CRISPR-Cas, its application and related advantages in oncology.

Characteristic miRNA expression signature and random forest survival analysis identify potential cancer-driving miRNAs in a broad range of head and neck squamous cell carcinoma subtypes

AIM

To characterize the miRNA expression profile in head and neck squamous cell carcinoma (HNSSC) accounting for a broad range of cancer subtypes and consequently identify an optimal miRNA signature with prognostic value.

BACKGROUND

HNSCC is consistently among the most common cancers worldwide. Its mortality rate is about 50% because of the characteristic aggressive behavior of these cancers and the prevalent late diagnosis. The heterogeneity of the disease has hampered the development of robust prognostic tools with broad clinical utility.

MATERIALS AND METHODS

The Cancer Genome Atlas HNSC dataset was used to analyze level 3 miRNA-Seq data from 497 HNSCC patients. Differential expression (DE) analysis was implemented using the limma package and multivariate linear model that adjusted for the confounding effects of age at diagnosis, gender, race, alcohol history, anatomic neoplasm subdivision, pathologic stage, T and N stages, and vital status. Random forest (RF) for survival analysis was implemented using the randomForestSRC package.

RESULTS

A characteristic DE miRNA signature of HNSCC, comprised of 11 upregulated (i.e., miR-196b-5p, miR-1269a, miR-196a-5p, miR-4652-3p, miR-210-3p, miR-1293, miR-615-3p, miR-503-5p, miR-455-3p, miR-205-5p, and miR-21-5p) and 9 downregulated (miR-376c-3p, miR-378c, miR-29c-3p, miR-101-3p, miR-195-5p, miR-299-5p, miR-139-5p, miR-6510-3p, miR-375) miRNAs was identified. An optimal RF survival model was built from seven variables including age at diagnosis, miR-378c, miR-6510-3p, stage N, pathologic stage, gender, and race (listed in order of variable importance).

CONCLUSIONS

The joint differential miRNA expression and survival analysis controlling for multiple confounding covariates implemented in this study allowed for the identification of a previously undetected prognostic miRNA signature characteristic of a broad range of HNSCC.

Emerging Role of CRISPR/Cas9 Technology for MicroRNAs Editing in Cancer Research

MicroRNAs (miRNA) are small, noncoding RNA molecules with a master role in the regulation of important tasks in different critical processes of cancer pathogenesis. Because there are different miRNAs implicated in all the stages of cancer, for example, functioning as oncogenes, this makes these small molecules suitable targets for cancer diagnosis and therapy. RNA-mediated interference has been one major approach for sequence-specific regulation of gene expression in eukaryotic organisms. Recently, the CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 system, first identified in bacteria and archaea as an adaptive immune response to invading genetic material, has been explored as a sequence-specific molecular tool for editing genomic sequences for basic research in life sciences and for therapeutic purposes. There is growing evidence that small noncoding RNAs, including miRNAs, can be targeted by the CRISPR/Cas9 system despite their lacking an open reading frame to evaluate functional loss. Thus, CRISPR/Cas9 technology represents a novel gene-editing strategy with compelling robustness, specificity, and stability for the modification of miRNA expression. Here, I summarize key features of current knowledge of genomic editing by CRISPR/Cas9 technology as a feasible strategy for globally interrogating miRNA gene function and miRNA-based therapeutic intervention. Alternative emerging strategies for nonviral delivery of CRISPR/Cas9 core components into human cells in a clinical context are also analyzed critically. Cancer Res; 77(24); 6812-7. ©2017 AACR.

PHGDH as a Key Enzyme for Serine Biosynthesis in HIF2α-Targeting Therapy for Renal Cell Carcinoma

Continuous activation of hypoxia-inducible factor (HIF) is important for progression of renal cell carcinoma (RCC) and acquired resistance to antiangiogenic multikinase and mTOR inhibitors. Recently, HIF2α antagonists PT2385 and PT2399 were developed and are being evaluated in a phase I clinical trial for advanced or metastatic clear cell RCC (ccRCC). However, resistance to HIF2α antagonists would be expected to develop. In this study, we identified signals activated by HIF2α deficiency as candidate mediators of resistance to the HIF2α antagonists. We established sunitinib-resistant tumor cells in vivo and created HIF2α-deficient variants of these cells using CRISPR/Cas9 technology. Mechanistic investigations revealed that a regulator of the serine biosynthesis pathway, phosphoglycerate dehydrogenase (PHGDH), was upregulated commonly in HIF2α-deficient tumor cells along with the serine biosynthesis pathway itself. Accordingly, treatment with a PHGDH inhibitor reduced the growth of HIF2α-deficient tumor cells in vivo and in vitro by inducing apoptosis. Our findings identify the serine biosynthesis pathway as a source of candidate therapeutic targets to eradicate advanced or metastatic ccRCC resistant to HIF2α antagonists. Cancer Res; 77(22); 6321-9. ©2017 AACR.

CRISPR/Cas9 editing reveals novel mechanisms of clustered microRNA regulation and function

MicroRNAs (miRNAs) are important regulators of diverse physiological and pathophysiological processes. MiRNA families and clusters are two key features in miRNA biology. Here we explore the use of CRISPR/Cas9 as a powerful tool to delineate the function and regulation of miRNA families and clusters. We focused on four miRNA clusters composed of miRNA members of the same family, homo-clusters or different families, hetero-clusters. Our results highlight different regulatory mechanisms in miRNA cluster expression. In the case of the miR-497~195 cluster, editing of miR-195 led to a significant decrease in the expression of the other miRNA in the cluster, miR-497a. Although no gene editing was detected in the miR-497a genomic locus, computational simulation revealed alteration in the three dimensional structure of the pri-miR-497~195 that may affect its processing. In cluster miR-143~145 our results imply a feed-forward regulation, although structural changes cannot be ruled out. Furthermore, in the miR-17~92 and miR-106~25 clusters no interdependency in miRNA expression was observed. Our findings suggest that CRISPR/Cas9 is a powerful gene editing tool that can uncover novel mechanisms of clustered miRNA regulation and function.

MiR-210-3p inhibits the tumor growth and metastasis of bladder cancer via targeting fibroblast growth factor receptor-like 1

Current evidence indicates that microRNAs are widely down-regulated in various tumors including colorectal carcinoma, liver cancer and lung cancer, and function as tumor suppressors through inhibiting cancer cell growth, invasion and migration. Here, we demonstrated that miR-210-3p level was significantly reduced in the bladder cancer compared to paratumor tissues, and attempt to reveal the regulatory role of miR-210-3p in bladder cancer progression. Exogenous overexpression of miR-210-3p inhibited the proliferation, migration and invasion of bladder cancer cells in vitro. In addition, the nude mouse xenograft model showed that miR-210-3p over-expressing inhibited bladder cancer growth and liver metastasis whereas silencing miR-210-3p caused an opposite outcome, which is mainly regulated by targeting fibroblast growth factor receptor-like 1 (FGFRL1). We also demonstrated that the expression of FGFRL1 in bladder cancer specimens were negatively correlated with miR-210-3p level, and FGFRL1 overexpression rescued the cell proliferation and invasion inhibited by ectopic expression of miR-210-3p. Moreover, knockdown of FGFRL1 was able to mimic the cell growth and metastasis effects induced by miR-210-3p over-expressing in bladder cancer cells. Together, these results indicate that miR-210-3p plays an important role in the regulation of bladder cancer growth and metastasis in vitro and in vivo through targeting FGFRL1.

Secreted miR-210-3p as non-invasive biomarker in clear cell renal cell carcinoma

The most common subtype of renal cell carcinoma (RCC) is clear cell RCC (ccRCC). It accounts for 70-80% of all renal malignancies representing the third most common urological cancer after prostate and bladder cancer. The identification of non-invasive biomarkers for the diagnosis and responsiveness to therapy of ccRCC may represent a relevant step-forward in ccRCC management. The aim of this study is to evaluate whether specific miRNAs deregulated in ccRCC tissues present altered levels also in urine specimens. To this end we first assessed that miR-21-5p, miR-210-3p and miR-221-3p resulted upregulated in ccRCC fresh frozen tissues compared to matched normal counterparts. Next, we evidenced that miR-210-3p resulted significantly up-regulated in 38 urine specimens collected from two independent cohorts of ccRCC patients at the time of surgery compared to healthy donors samples. Of note, miR-210-3p levels resulted significantly reduced in follow-up samples. These results point to miR-210-3p as a potential non-invasive biomarker useful not only for diagnosis but also for the assessment of complete resection or response to treatment in ccRCC management.

[ARTICLE WITHDRAWN] MicroRNA-539 Inhibits the Epithelial-Mesenchymal Transition of Esophageal Cancer Cells by Twist-Related Protein 1-Mediated Modulation of Melanoma-Associated Antigen A4

This article has been withdrawn at the request of the publisher in December 2020.

Impact of MicroRNAs in the Cellular Response to Hypoxia

In mammalian cells, hypoxia, or inadequate oxygen availability, regulates the expression of a specific set of MicroRNAs (MiRNAs), termed "hypoxamiRs." Over the past 10 years, the appreciation of the importance of hypoxamiRs in regulating the cellular adaptation to hypoxia has grown dramatically. At the cellular level, each hypoxamiR, including the master hypoxamiR MiR-210, can simultaneously regulate expression of multiple target genes in order to fine-tune the adaptive response of cells to hypoxia. This review addresses the complex molecular regulation of MiRNAs in both physiological and pathological conditions of low oxygen adaptation and the multiple functions of hypoxamiRs in various hypoxia-associated biological processes, including apoptosis, survival, proliferation, angiogenesis, inflammation, and metabolism. From a clinical perspective, we also discuss the potential use of hypoxamiRs as new biomarkers and/or therapeutic targets in cancer and aging-associated diseases including cardiovascular and fibroproliferative disorders.