microRNA-193a-3p is specifically down-regulated and acts as a tumor suppressor in BRAF-mutated colorectal cancer

Parietal Epithelial Cell Behavior and Its Modulation by microRNA-193a

Glomerular parietal epithelial cells (PECs) have been increasingly recognized to have crucial functions. Lineage tracking in animal models showed the expression of a podocyte phenotype by PECs during normal glomerular growth and after acute podocyte injury, suggesting a reparative role of PECs. Conversely, activated PECs are speculated to be pathogenic and comprise extracapillary proliferation in focal segmental glomerulosclerosis (FSGS) and crescentic glomerulonephritis (CrescGN). The reparative and pathogenic roles of PECs seem to represent two sides of PEC behavior directed by the local milieu and mediators. Recent studies suggest microRNA-193a (miR193a) is involved in the pathogenesis of FSGS and CrescGN. In a mouse model of primary FSGS, the induction of miR193a caused the downregulation of Wilms' tumor protein, leading to the dedifferentiation of podocytes. On the other hand, the inhibition of miR193a resulted in reduced crescent lesions in a mouse model of CrescGN. Interestingly, in vitro studies report that the downregulation of miR193a induces trans-differentiation of PECs into a podocyte phenotype. This narrative review highlights the critical role of PEC behavior in health and during disease and its modulation by miR193a.

Transcriptomic and Functional Evidence That miRNA193a-3p Inhibits Lymphatic Endothelial Cell (LEC) and LEC + MCF-7 Spheroid Growth Directly and by Altering MCF-7 Secretome

MicroRNA 193a-3p (miR193a-3p) is a short non-coding RNA with tumor suppressor properties. Breast cancer (BC) progression is governed by active interaction between breast cancer cells, vascular (V)/lymphatic (L) endothelial cells (ECs), and BC secretome. We have recently shown that miR193a-3p, a tumor suppressor miRNA, inhibits MCF-7 BC cell-driven growth of VECs via direct antimitogenic actions and alters MCF-7 secretome. Since LEC-BC cross-talk plays a key role in BC progression, we investigated the effects of miR193a-3p on MCF-7 secretome and estradiol-mediated growth effects in LECs and LEC + MCF-7 spheroids, and delineated the underlying mechanisms. Transfection of LECs with miR193a-3p, as well as secretome from MCF-7 transfected cells, inhibited LEC growth, and these effects were mimicked in LEC + MCF-7 spheroids. Moreover, miR193a-3p inhibited ERK1/2 and Akt phosphorylation in LECs and LEC + MCF-7 spheroids, which are importantly involved in promoting cancer development and metastasis. Treatment of LECs and LEC + MCF-7 spheroids with estradiol (E2)-induced growth, as well as ERK1/2 and Akt phosphorylation, and was abrogated by miR193a-3p and secretome from MCF-7 transfected cells. Gene expression analysis (GEA) in LEC + MCF-7 spheroids transfected with miR193a-3p showed significant upregulation of 54 genes and downregulation of 73 genes. Pathway enrichment analysis of regulated genes showed significant modulation of several pathways, including interferon, interleukin/cytokine-mediated signaling, innate immune system, ERK1/2 cascade, apoptosis, and estrogen receptor signaling. Transcriptomic analysis showed downregulation in interferon and anti-apoptotic and pro-growth molecules, such as IFI6, IFIT1, OSA1/2, IFITM1, HLA-A/B, PSMB8/9, and PARP9, which are known to regulate BC progression. The cytokine proteome array of miR193a-3p transfected MCF secretome and confirmed the upregulation of several growth inhibitory cytokines, including IFNγ, Il-1a, IL-1ra, IL-32, IL-33, IL-24, IL-27, cystatin, C-reactive protein, Fas ligand, MIG, and sTIM3. Moreover, miR193a-3p alters factors in MCF-7 secretome, which represses ERK1/2 and Akt phosphorylation, induces pro-apoptotic protein and apoptosis in LECs, and downregulates interferon-associated proteins known to promote cancer growth and metastasis. In conclusion, miR193a-3p can potentially modify the tumor microenvironment by altering pro-growth BC secretome and inhibiting LEC growth, and may represent a therapeutic molecule to target breast tumors/cancer.

Non-Coding RNAs Regulate the Resistance to Anti-EGFR Therapy in Colorectal Cancer

Colorectal cancer (CRC) is the third prevalent cancer worldwide, the morbidity and mortality of which have been increasing in recent years. As molecular targeting agents, anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (McAbs) have significantly increased the progression-free survival (PFS) and overall survival (OS) of metastatic CRC (mCRC) patients. Nevertheless, most patients are eventually resistant to anti-EGFR McAbs. With the intensive study of the mechanism of anti-EGFR drug resistance, a variety of biomarkers and pathways have been found to participate in CRC resistance to anti-EGFR therapy. More and more studies have implicated non-coding RNAs (ncRNAs) primarily including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), are widely involved in tumorigenesis and tumor progression. They function as essential regulators controlling the expression and function of oncogenes. Increasing data have shown ncRNAs affect the resistance of molecular targeted drugs in CRC including anti-EGFR McAbs. In this paper, we have reviewed the advance in mechanisms of ncRNAs in regulating anti-EGFR McAbs therapy resistance in CRC. It provides insight into exploring ncRNAs as new molecular targets and prognostic markers for CRC.

Tumor suppressor miR-193a-3p enhances efficacy of BRAF/MEK inhibitors in BRAF-mutated colorectal cancer

Patients with BRAF‐mutated colorectal cancer (CRC) have a poor prognosis despite recent therapeutic advances such as combination therapy with BRAF, MEK, and epidermal growth factor receptor (EGFR) inhibitors. To identify microRNAs (miRNAs) that can improve the efficacy of BRAF inhibitor dabrafenib (DAB) and MEK inhibitor trametinib (TRA), we screened 240 miRNAs in BRAF‐mutated CRC cells and identified five candidate miRNAs. Overexpression of miR‐193a‐3p, one of the five screened miRNAs, in CRC cells inhibited cell proliferation by inducing apoptosis. Reverse‐phase protein array analysis revealed that proteins with altered phosphorylation induced by miR‐193a‐3p were involved in several oncogenic pathways including MAPK‐related pathways. Furthermore, overexpression of miR‐193a‐3p in BRAF‐mutated cells enhanced the efficacy of DAB and TRA through inhibiting reactivation of MAPK signaling and inducing inhibition of Mcl1. Inhibition of Mcl1 by siRNA or by Mcl1 inhibitor increased the antiproliferative effect of combination therapy with DAB, TRA, and anti‐EGFR antibody cetuximab. Collectively, our study demonstrated the possibility that miR‐193a‐3p acts as a tumor suppressor through regulating multiple proteins involved in oncogenesis and affects cellular sensitivity to MAPK‐related pathway inhibitors such as BRAF inhibitors, MEK inhibitors, and/or anti‐EGFR antibodies. Addition of miR‐193a‐3p and/or modulation of proteins involved in the miR‐193a‐3p–mediated pathway, such as Mcl1, to EGFR/BRAF/MEK inhibition may be a potential therapeutic strategy against BRAF‐mutated CRC.

4-Acetyl-Antroquinonol B Improves the Sensitization of Cetuximab on Both Kras Mutant and Wild Type Colorectal Cancer by Modulating the Expression of Ras/Raf/miR-193a-3p Signaling Axis

The KRAS mutation is one of the leading driver mutations in colorectal cancer (CRC), and it is usually associated with poor prognosis and drug resistance. Therapies targeting the epidermal growth factor receptor (EFGR) are widely used for end-stage CRC. However, patients with KRAS mutant genes cannot benefit from this therapy because of Ras signaling activation by KRAS mutant genes. Our previous study revealed the anti-proliferative effect of 4-acetyl-antroquinonol B (4-AAQB) on CRC cells, but whether the drug is effective in KRAS-mutant CRC remains unknown. We screened CRC cell lines harboring the KRAS mutation, namely G12A, G12C, G12V and G13D, with one wild type cell line as the control; SW1463 and Caco-2 cell lines were used for further experiments. Sulforhodamine B assays, together with the clonogenicity and invasion assay, revealed that KRAS-mutant SW1463 cells were resistant to cetuximab; however, 4-AAQB treatment effectively resensitized CRC cells to cetuximab through the reduction of colony formation, invasion, and tumorsphere generation and of oncogenic KRAS signaling cascade of CRC cells. Thus, inducing cells with 4-AAQB before cetuximab therapy could resensitize KRAS-mutant, but not wild-type, cells to cetuximab. Therefore, we hypothesized that 4-AAQB can inhibit KRAS. In silico analysis of the publicly available GEO (GSE66548) dataset of KRAS-mutated versus KRAS wild-type CRC patients confirmed that miR-193a-3p was significantly downregulated in the former compared with the latter patient population. Overexpression of miR-193a-3p considerably reduced the oncogenicity of both CRC cells. Furthermore, KRAS is a key target of miR-193a-3p. In vivo treatment with the combination of 4-AAQB and cetuximab significantly reduced the tumor burden of a xenograft mice model through the reduction of the expression of oncogenic markers (EGFR) and p-MEK, p-ERK, and c-RAF/p-c-RAF signaling, with the simultaneous induction of miR-193a-3p expression in the plasma. In summary, our findings provide strong evidence regarding the therapeutic effect of 4-AAQB on KRAS-mutant CRC cells. Furthermore, 4-AAQB effectively inhibits Ras singling in CRC cells, through which KRAS-mutant CRC can be resensitized to cetuximab.

MicroRNA miR-425 promotes tumor progression by inhibiting Dickkopf-related protein-3 in gastric cancer

Gastric cancer is a prevalent yet heterogeneous disease which ranks as the fifth most common cancer in the world. Dietary habit, genetic background, Helicobacter Pylori infections were the risk factors of gastric cancer. MicroRNA miR-425 is highly expressed in gastric cancer, but little attention has been devoted to the mechanism of miR-425 in tumorigenesis. This study aim to investigate the role of miR-425 in gastric cancer.The expression of miR-425 and Dickkopf-related protein-3(DKK-3) were analyzed by qRT-PCR. Gastric cell line BGC-823 and SGC-7901 were transfected miR-425 inhibitors or NC. Then, cell viability was determined by CCK-8, cell apoptosis and cell cycle were assessed by flow cytometer. Cell migration and cell invasion were analyzed by wound healing and trans-well assays. Luciferase reporter assay was conducted to assess the correlation between miR-425 and DKK-3. Downstream regulators, such as p-ASK1 and p-JNK, were analysis by western blot.Compared with normal gastric epithelium cell line, miR-425 was obviously upregulated in gastric cancer cell lines. MiR-425 inhibitor suppressed the cell viability, cell migration and cell invasion. The Luciferase assay data identified that DKK-3 is a target of miR-425. While miR-425 could lower the expression of DKK-3 which mediate tumorigenesis in a certain way.

MicroRNAs and angiogenesis: a new era for the management of colorectal cancer

MicroRNAs (miRNAs) are a class of small noncoding RNA molecules containing only 20–22 nucleotides. MiRNAs play a role in gene silencing and translation suppression by targeting and binding to mRNA. Proper control of miRNA expression is very important for maintaining a normal physiological environment because miRNAs can affect most cellular pathways, including cell cycle checkpoint, cell proliferation, and apoptosis pathways, and have a wide range of target genes. With these properties, miRNAs can modulate multiple signalling pathways involved in cancer development, such as cell proliferation, apoptosis, and migration pathways. MiRNAs that activate or inhibit the molecular pathway related to tumour angiogenesis are common topics of research. Angiogenesis promotes tumorigenesis and metastasis by providing oxygen and diffusible nutrients and releasing proangiogenic factors and is one of the hallmarks of tumour progression. CRC is one of the most common tumours, and metastasis has always been a difficult issue in its treatment. Although comprehensive treatments, such as surgery, radiotherapy, chemotherapy, and targeted therapy, have prolonged the survival of CRC patients, the overall response is not optimistic. Therefore, there is an urgent need to find new therapeutic targets to improve CRC treatment. In a series of recent reports, miRNAs have been shown to bidirectionally regulate angiogenesis in colorectal cancer. Many miRNAs can directly act on VEGF or inhibit angiogenesis through other pathways (HIF-1a, PI3K/AKT, etc.), while some miRNAs, specifically many exosomal miRNAs, are capable of promoting CRC angiogenesis. Understanding the mechanism of action of miRNAs in angiogenesis is of great significance for finding new targets for the treatment of tumour angiogenesis. Deciphering the exact role of specific miRNAs in angiogenesis is a challenge due to the high complexity of their actions. Here, we describe the latest advances in the understanding of miRNAs and their corresponding targets that play a role in CRC angiogenesis and discuss possible miRNA-based therapeutic strategies.

The Role of microRNAs in Development of Colitis-Associated Colorectal Cancer

Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18-25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes' expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment.

microR-4449 Promotes Colorectal Cancer Cell Proliferation via Regulation of SOCS3 and Activation of STAT3 Signaling

Introduction

Dysregulation of microRNAs (miRNAs), which represented a critical level of gene expression modulation, regulated the development of colorectal cancer. However, the functions of numerous miRNAs remain unclear in colorectal cancer.

Methods

The microarray data of GSE115513 were retrieved; subsequently, the differentially expressed miRNAs between 411 colon tumors and 381 normal colon mucosa were analyzed. Real-time PCR (RT-qPCR) and bioinformatic analysis were applied to examine the expression of miR-4449 in collected colorectal tumors and published microarray data. The activity of signal transducer and activator of transcription 3 (STAT3) signaling was detected by Western blotting and RT-qPCR. Dual-Luciferase assay and bioinformatic analysis were used to confirm the interaction between suppressor of cytokine signaling 3 (SOCS3) and miR-4449. Loss of function and rescue assays were performed to study the involvement of miR-4449 and SOCS3 in cell proliferation and apoptosis of colorectal cancer.

Results

Herein, we identified miR-4449 as a novel upregulated miRNA in colorectal cancer. Our data suggested that miR-4449 downregulation blocked the proliferation of colorectal cancer cells accompanied with the elevation of cell apoptosis. Decreased expression of miR-4449 led to inactivation of STAT3 pathway as indicated by dephosphorylation of STAT3 and downregulation of STAT3 target genes, including vascular endothelial growth factor (VEGF), c-Myc, baculovirus inhibitor of apoptosis containing 5 (BIRC5). Furthermore, SOCS3, a negative regulator of STAT3 pathway, was found to be a target gene of miR-4449. The data also showed that the inactivation of STAT3 pathway by miR-4449 inhibitor was realized by targeting SOCS3. Moreover, the biological function of miR-4449 downregulation was reversed by SOCS3 knockdown in colorectal cancer cells.

Conclusion

The current study revealed that miR-4449 promoted cell proliferation of colorectal cancer and was a promising potential therapeutic target for colorectal cancer.

Circulating let-7e-5p, miR-106a-5p, miR-28-3p, and miR-542-5p as a Promising microRNA Signature for the Detection of Colorectal Cancer

Simple Summary

The detection of early-stage colorectal cancer increases the chance to prevent tumor progression and death by the disease. Colonoscopy is one sensitive screening test to detect malignant or potentially malignant lesions in the intestines. However, it has some disadvantages, including sedation requirements, increased risk of colon perforation, and bleeding. Circulating microRNAs (miRNAs) in plasma or serum from cancer patients have been investigated and described as potential diagnostic or prognostic markers. We conducted an miRNAs screening test in plasma samples from colorectal cancer patients and subjects without cancer, aiming to identify markers for the early detection of the disease. We identified and validated four miRNAs capable of distinguishing cancer from non-cancer cases. Our non-invasive diagnostic biomarkers presented high performance and are easily applicable to clinical practice.

Abstract

Colorectal cancer (CRC) is a disease with high incidence and mortality. Colonoscopy is a gold standard among tests used for CRC traceability. However, serious complications, such as colon perforation, may occur. Non-invasive diagnostic procedures are an unmet need. We aimed to identify a plasma microRNA (miRNA) signature for CRC detection. Plasma samples were obtained from subjects (n = 109) at different stages of colorectal carcinogenesis. The patients were stratified into a non-cancer (27 healthy volunteers, 17 patients with hyperplastic polyps, 24 with adenomas), and a cancer group (20 CRC and 21 metastatic CRC). miRNAs (381) were screened by TaqMan Low-Density Array. A classifier based on four differentially expressed miRNAs (miR-28-3p, let-7e-5p, miR-106a-5p, and miR-542-5p) was able to discriminate cancer versus non-cancer cases. The overexpression of these miRNAs was confirmed by RT-qPCR, and a cross-study validation step was implemented using eight data series retrieved from Gene Expression Omnibus (GEO). In addition, another external data validation using CRC surgical specimens from The Cancer Genome Atlas (TCGA) was carried out. The predictive model’s performance in the validation set was 76.5% accuracy, 59.4% sensitivity, and 86.8% specificity (area under the curve, AUC = 0.716). The employment of our model in the independent publicly available datasets confirmed a good discrimination performance in five of eight datasets (median AUC = 0.823). Applying this algorithm to the TCGA cohort, we found 99.5% accuracy, 99.7% sensitivity, and 90.9% specificity (AUC = 0.998) when the model was applied to solid colorectal tissues. Overall, we suggest a novel signature of four circulating miRNAs, i.e., miR-28-3p, let-7e-5p, miR-106a-5p, and miR-542-5p, as a predictive tool for the detection of CRC.

miR-193a-3p Promotes the Invasion, Migration, and Mesenchymal Transition in Glioma through Regulating BTRC

Background

The present study is aimed at exploring the specific expression of miR-193a-3p and the mechanism underlying miR-193a-3p-mediated mesenchymal transition (MT), invasion, and migration in glioma.

Methods

The gene expression profile datasets of GSE39486 and GSE25676 were downloaded from the National Center for Biotechnology (NCBI). Data regarding the expression of miR-193a-3p and survival curves were derived from Chinese Glioma Genome Atlas (CGGA). Online websites including miRWalk, DIANA, and starbase were employed to predict the target genes for miR-193a-3p. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed by the Omicsbean online software. Module analysis of the protein-protein interaction (PPI) networks was performed by the plug-in Molecular Complex Detection (MCODE), and the degrees of genes were calculated by CytoHubba plug-in of Cytoscape. Survival curves were based on the Gene Expression Profile Interaction Analysis (GEPIA). Transwell, wound healing, and Western blot experiments were performed to investigate the effects of miR-193a-3p and beta-transducin repeat containing E3 ubiquitin protein ligase (BTRC) on the invasion, migration, and MT of glioma.

Results

miR-193a-3p was highly expressed in glioma tissues and significantly correlated with poor survival in patients with glioma. The target genes for miR-193a-3p were involved in many cancer-related signaling pathways. The PPI showed 11 genes with both high degrees and MCODE scores in the network. Survival analysis demonstrated that the expression of BTRC was significantly correlated with the prognosis of patients with glioma. The results from the transwell, wound healing, and Western blot analyses suggested that miR-193a-3p promoted the invasion, migration, and MT of glioma cells, which could be reversed by BTRC.

Conclusions

miR-193a-3p was upregulated in patients with glioma and could affect the invasion, migration, and MT of glioma by regulating BTRC.

Temozolomide modulates the expression of miRNAs in colorectal cancer

Cancer is the second leading cause of death globally, where nearly 1 in 6 deaths is due to cancer, with 70% of all deaths from cancer occur in low- and middle-income countries. The overall lifetime risk of developing colorectal cancer is 1 in 22 in men and 1 in 24 in women. In this work, we aimed to evaluate the role of temozolomide (TMZ) in controlling colon cancer cells (CRC) via regulating the miRnome. For this purpose, CRC cells (CaCo-2) were treated with 50 µM of TMZ for 48 h. Cell count using trypan test and cytotoxicity using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) were carried out, and the obtained results indicated a significant decrease in cell count (p = 0.029), and in the cell viability (p = 0.0019). Cell cycle analysis was performed using flow cytometer, and results showed that TMZ arrested CRC cells at G2/M phase. A total of 84 miRNAs were profiled using real time PCR, and the results indicated that TMZ treatment upregulated 15 of 84 miRNAs panel profiled and downregulated the rest. The TMZ-upregulated/downregulated miRNAs were predicted to interact with many epigenetic-related proteins i.e., DNMTs, EZH2, and SUV31H1. This study shed some light on the role of TMZ in regulating the miRnome of CRC and hence in different types of cancers.

Downregulation of miR‑193a‑3p via targeting cyclin D1 in thyroid cancer

Thyroid cancer (TC) is a frequently occurring malignant tumor with a rising steadily incidence. microRNA (miRNA/miR)‑193a‑3p is an miRNA that is associated with tumors, playing a crucial role in the genesis and progression of various cancers. However, the expression levels of miR‑193a‑3p and its molecular mechanisms in TC remain to be elucidated. The present study aimed to probe the expression of miR‑193a‑3p and its clinical significance in TC, including its underlying molecular mechanisms. Microarray and RNA sequencing data gathered from three major databases, specifically Gene Expression Omnibus (GEO), ArrayExpress and The Cancer Genome Atlas (TCGA) databases, and the relevant data from the literature were used to examine miR‑193a‑3p expression. Meta‑analysis was also conducted to evaluate the association between clinicopathological parameters and miR‑193a‑3p in 510 TC and 59 normal samples from the TCGA database. miRWalk 3.0, and the TCGA and GEO databases were used to predict the candidate target genes of miR‑193a‑3p. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and protein‑protein interaction network enrichment analyses were conducted by using the predicted candidate target genes to investigate the underlying carcinogenic mechanisms. A dual luciferase assay was performed to validate the targeting regulatory association between the most important hub gene cyclin D1 (CCND1) and miR‑193a‑3p. miR‑193a‑3p expression was considerably downregulated in TC compared with in the non‑cancer controls (P<0.001). The area under the curve of the summary receiver operating characteristic was 0.80. Downregulation of miR‑193a‑3p was also significantly associated with age, sex and metastasis (P=0.020, 0.044 and 0.048, respectively). Bioinformatics analysis indicated that a low miR‑193a‑3p expression may augment CCND1 expression to affect the biological processes of TC. In addition, CCND1, as a straightforward target, was validated through a dual luciferase assay. miR‑193a‑3p and CCND1 may serve as prognostic biomarkers of TC. Finally, miR‑193a‑3p may possess a crucial role in the genesis and progression of TC by altering the CCND1 expression.

miR-140-3p Suppresses Cell Growth And Induces Apoptosis In Colorectal Cancer By Targeting PD-L1

Background

A variety of miRNAs have been recently reported to be abnormally expressed in colorectal cancer (CRC). A growing number of studies have demonstrated that aberrantly expressed miRNAs are closely related to the development and progression of CRC. It has been found that miR-140-3p plays a vital role in several cancers. However, its expression, roles and mechanisms in CRC are remain unknown.

Materials and methods

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to determine miR-140-3p expression in CRC tissues and cell lines. CCK8, migration, invasion and flow cytometric assays were used to determine the influence of miR-140-3p upregulation on cell proliferation, migration, invasion and apoptosis of CRC cells. Luciferase reporter assays and Western blots were utilized to identify the target genes of miR-140-3p. In addition, the potential mechanism of miR-140-3p action in CRC cells was elucidated.

Results

In our study, miR-140-3p expression was significantly decreased in CRC tissues and cell lines. Overexpression of miR-140-3p attenuated proliferation, migration, and invasion and induced the apoptosis of CRC cells. Bioinformatics analyse and luciferase reporter analysis identified PD-L1 as a putative target gene of miR-140-3p. PD-L1 was overexpressed in CRC tissues and inversely correlated with miR-140-3p expression. Suppression of PD-L1 expression in CRC cells generated biological behaviours in CRC cells that were similar to those observed after treated with miR-140-3p mimics. Restoration of PD-L1 expression partially attenuated the inhibitory effect of miR-140-3p on CRC cells. Western blot were used to verify the effect of PD-L1 expression on PI3K/AKT pathway. In addition, overexpression of miR-140-3p could inhibit CRC tumor growth in vivo.

Conclusion

In general, these data demonstrate that miR-140-3p acts as a tumour suppressor in CRC by directly targeting PD-L1 and inactivating PI3K/AKT pathway, suggesting that miR-140-3p might be a novel target for CRC diagnosis and treatment.

Explore prognostic marker of colorectal cancer based on ceRNA network

Colorectal cancer (CRC) is one of the most common malignant tumors in the world. With the deepening of people's understanding of CRC at the molecular level, the survival and prognosis of CRC have been significantly improved with the help of surgery, radiotherapy, and chemotherapy, molecular targeted biological therapy and early detection of diseases. The research of different disciplines and the development of multihistological analysis in recent years have proved that the occurrence and development of CRC is a complex biological process with the common action of multiple factors, which involves the huge changes of various histological levels such as the genome, transcriptome, and epigenome. At present, the abnormal expression of protein products in the transcription process has attracted more and more attention. Based on the sensitivity and timeliness of its changes, it has become a hot topic to study the occurrence and development mechanism of CRC through transcriptome changes, so as to provide markers for early diagnosis and prognosis. In recent years, competitive endogenous RNA (ceRNA) has become one of the hot topics in cancer research. The ceRNA hypothesis holds that transcripts such as long noncoding RNA can competitively bind microRNA (miRNA), thus preventing miRNA from binding to messenger RNA (mRNA) and thereby regulating the expression of mRNA. At present, the interaction mechanism of ceRNA in CRC is still unclear, and exploring its interaction relationship is of great significance to elucidate the occurrence and development mechanism of CRC. In this study, we used The Cancer Genome Atlas (TCGA) RNA - seq data of colorectal Cancer and microRnas - seq data to construct colorectal Cancer ceRNA topology network to mine key RNAs that influence the prognosis of colorectal cancer, providing potential RNA biomarkers.

Significance of miR-27a and miR-31 in early diagnosis and prognosis of colorectal cancer

Clinical significance of micro-ribonucleic acid (miR)-27a and miR-31 in the early diagnosis and prognosis of colorectal cancer were investigated. Forty patients with colorectal malignancy admitted to Xintai People's Hospital from February 2014 to April 2018 were enrolled as the observation group, of which 30 patients were diagnosed via pathological biopsy. Another 40 patients diagnosed with colorectal polyp and receiving surgical treatment were selected as the control group. The relative amount of miR-27a and miR-31 was measured. The relative expression levels of miR-27a and miR-31 in patients were analyzed. The diagnostic sensitivity, specificity and accordance rates of positive miR-27a and miR-31 expression in colorectal cancer were recorded. The correlation of the relative expression levels of miR-27a and miR-31 with the survival time of patients were analyzed. In the observation group, the relative expression levels of miR-27a and miR-31 in patients with lymph node metastasis and distant metastasis were higher than those in patients without lymph node metastasis and distant metastasis (P<0.05). Histological type of patients with non-mucinous carcinoma had increased relative expression levels of miR-27a and miR-31 in comparison with those with mucinous carcinoma (P<0.05). In terms of Duke's grade, the relative expression levels of miR-27a and miR-31 in patients with grade C and D were higher than those in patients with grade A and B (P<0.05). The diagnostic sensitivity, specificity and accordance rate of positive miR-27a expression were lower than those of positive miR-31 expression. The relative expression levels of miR-27a and miR-31 were positively correlated with the survival time of patients (P<0.05). The expression levels of miR-27a and miR-31 are related to distant metastasis and tumor grade of patients with colorectal cancer, and positively associated with the survival time of patients, having high diagnostic value.

MicroRNA-193a-3p suppresses the colorectal cancer cell proliferation and progression through downregulating the PLAU expression

Background

Colorectal cancer (CRC) is one of the leading causes of cancer-related death in China. Dysregulation of microRNAs (miRNAs) is involved in cancer development and progression. Our previous study showed an inverse relationship between miR-193a-3p expression and the prognosis of CRC. However, the exact biological functions of miR-193a-3p in CRC are still poorly understood. This study aimed to explore the role and mechanism of miR-193a-3p in CRC.

Methods

Real-time PCR and Western blotting were used to examine the expression levels of RNA and protein, respectively. A dual luciferase assay was performed to validate predicted targets of miR-193a-3p. Loss and gain-of-function studies were carried out to reveal the effects and potential mechanism of the miR-193a-3p in the proliferation, metastasis and angiogenesis of CRC cells.

Results

The expression levels of miR-193a-3p in human CRC cell lines were significantly decreased compared with that in normal colonic epithelium cell line. Furthermore, plasminogen activator urokinase (PLAU) was validated as a direct target gene of miR-193a-3p. Over-expression of miR-193a-3p inhibited proliferation, migration and angiogenesis of HT-29 cell, whereas forced expression of PLAU could rescue the inhibitory effects.

Conclusion

miR-193a-3p might inhibit CRC cell growth, migration and angiogenesis partly through targeting PLAU. MiR-193a-3p/PLAU axis might provide a potent therapeutic opportunity for aggressive CRC.

MiR-193a-3p inhibits pancreatic ductal adenocarcinoma cell proliferation by targeting CCND1

Background: MicroRNAs (miRNAs) could modulate gene expression at the posttranscriptional level by promoting mRNA degradation or blocking mRNA translation, thus affecting the occurrence and development of cancer. Methods: In this work, qRT-PCR was conducted to detect the expression of miR-193a-3p and CCND1. The ability of cell proliferation was evaluated via CCK-8 assay. Cell apoptosis and cell cycle distribution were detected by flow cytometry. Bioinformatic techniques were employed to research the regulatory relationship between miR-193a-3p and target genes. The relationship between miR-193a-3p and CCND1 was verified via dual-luciferase reporter assays. Results: MiR-193a-3p expression in pancreatic ductal adenocarcinoma (PDAC) tissue was significantly lower than in non-cancerous tissue. After overexpressing miR-193a-3p in PDAC cells, their multiplication ability was significantly inhibited, apoptosis was accelerated, and the cell cycle was blocked in the G1 and G2/M phases. CCND1 was confirmed to have a targeted relationship with miR-193a-3p. Moreover, CCND1 expression was significantly lower in PDAC cells with an overexpression of miR-193a-3p. Conclusions: MiR-193a-3p targeted CCND1 to suppress tumor growth in PDAC cells. MiR-193a-3p may function as a tumor inhibitor in PDAC development, which could offer a promising therapeutic and prognostic strategy for PDAC treatment.

Biomarkers for Stratification in Colorectal Cancer: MicroRNAs

Colorectal cancer (CRC) is one of the most widely recognized and deadly malignancies worldwide. In spite of the fact that the death rates have declined over the previous decade, particularly because of enhanced screening or potential treatment alternatives, CRC still remains the third leading cause of cancer-related mortality in the world, with an estimated incidence of over 1 million new cases and approximately 600 000 deaths estimated yearly. Unlike prostate and lung cancer, CRC is not easily detectable in its early stage, which may also account for its high mortality rate. MicroRNAs (miRNAs) are a class of noncoding RNAs. The roles of these noncoding RNAs have been implicated in cancer pathogenesis, most especially CRC, due to their ability to posttranscriptionally regulate the expression of oncogenes and tumor suppressor genes. Dysregulated expression of many miRNAs regulates the expression of hundreds of growth regulatory genes and pathways that are important in the multistep model of colorectal carcinogenesis. If CRC is detected early, it is a largely treatable disease. Early diagnosis, including the identification of premalignant adenomas, is regarded a major concept for improving patient survival in CRC treatment. Several lines of research suggest that miRNAs are closely implicated in the metastatic process in CRC and some of these miRNAs could be useful as promising clinical tools for identifying specific stages of CRC due to their differential expression. This review discusses the correlation between CRC staging relative to the specific expression of miRNA for early detection, treatment, and disease management.

Epigenetic Regulation by lncRNAs: An Overview Focused on UCA1 in Colorectal Cancer

Colorectal cancers have become the second leading cause of cancer-related deaths. In particular, acquired chemoresistance and metastatic lesions occurring in colorectal cancer are a major challenge for chemotherapy treatment. Accumulating evidence shows that long non-coding (lncRNAs) are involved in the initiation, progression, and metastasis of cancer. We here discuss the epigenetic mechanisms through which lncRNAs regulate gene expression in cancer cells. In the second part of this review, we focus on the role of lncRNA Urothelial Cancer Associated 1 (UCA1) to integrate research in different types of cancer in order to decipher its putative function and mechanism of regulation in colorectal cancer cells. UCA1 is highly expressed in cancer cells and mediates transcriptional regulation on an epigenetic level through the interaction with chromatin modifiers, by direct regulation via chromatin looping and/or by sponging the action of a diversity of miRNAs. Furthermore, we discuss the role of UCA1 in the regulation of cell cycle progression and its relation to chemoresistance in colorectal cancer cells.

miR-206 Inhibits Cell Proliferation, Migration, and Invasion by Targeting BAG3 in Human Cervical Cancer

miR-206 and Bcl-2-associated athanogene 3 (BAG3) have been suggested as important regulators in various cancer types. However, the biological role of miR-206 and BAG3 in cervical cancer (CC) remains unclear. We investigated the expressions and mechanisms of miR-206 and BAG3 in CC using in vitro and in vivo assays. In the present study, miR-206 expression was expressed at a lower level in CC tissues and cells than adjacent normal tissues and NEECs. By contrast, BAG3 mRNA and protein were expressed at higher levels in CC tissues and cells. Furthermore, miR-206 overexpression repressed cell proliferation, migration, and invasion in vitro, and the 3′-untranslated region (3′-UTR) of BAG3 was a direct target of miR-206. miR-206 overexpression also inhibited EGFR, Bcl-2, and MMP2/9 protein expression, but promoted Bax protein expression. Besides, BAG3 overexpression partially abrogated miR-206-inhibited cell proliferation and invasion, while BAG3 silencing enhanced miR-206-mediated inhibition. In vivo assay revealed that miR-206 repressed tumor growth in nude mice xenograft model. In conclusion, miR-206 inhibits cell proliferation, migration, and invasion by targeting BAG3 in human CC. Thus, miR-206-BAG3 can be used as a useful target for CC.