MiRNA-203 suppresses cell proliferation, migration and invasion in colorectal cancer via targeting of EIF5A2

Molecular mechanism of miR-203a targeting Runx2 to regulate thiram induced-chondrocyte development

Thiram is a kind of organic compound, which is commonly used for sterilization, insecticidal and deodorization in daily life. Its toxicology has been broadly studied. Recently, more and more microRNAs have been shown to participate in the regulation of cartilage development. However, the potential mechanism by which microRNA regulates chondrocyte growth is still unclear. Our experiments have demonstrated that thiram can hamper chondrocytes development and cause a significant increase in miR-203a content in vitro and in vivo trials. miR-203a mimic significantly decrease in mRNA and protein expression of Wnt4, Runx2, COL2A1, β-catenin and ALP, and significantly enhance the mRNA and protein levels of GSK-3β. It has been observed that overexpression of miR-203a hindered chondrocytes development. In addition, Runx2 was confirmed to be a direct target of miR-203a by dual luciferase report gene assay. Transfection of si-Runx2 into chondrocytes reveals that significant downregulation of genes is associated with cartilage development. Overall, these results suggest that overexpression of miR-203a inhibits the expression of Runx2. These findings are conducive to elucidate the mechanism of chondrocytes dysplasia induced by thiram and provide new research ideas for the toxicology of thiram.

Exosome miRNA-203 promotes M1 macrophage polarization and inhibits prostate cancer tumor progression

Prostate cancer (PCa) is a prevalent malignant neoplasm affecting the male reproductive system globally. However, the diagnostic and therapeutic approaches fall short of meeting the demands posed by PCa. Poor expression of miRNA-203 (miR-203) within PCa tissues and cells implies its potential utility as a diagnostic indicator for PCa. Exosomes (Exo), membranous vesicles released by various cells, are rich reservoirs of miRNAs. However, the presence of miR-203 presents within Exo derived from PCa cells remains unclarified. In this study, Exo was isolated from urine specimens collected from clinical PCa patients and LNCaP cells to detect miR-203 expression. Meanwhile, the impact of overexpressed miR-203 on M0 macrophages (mø) was analyzed. Subsequently, alterations in the proliferative, migratory, and invasive capacities of LNCaP cells were examined within a co-culture system featuring elevated miR-203 levels in both macrophages and LNCaP cells. Furthermore, the repercussions of miR-203 upregulation or inhibition were explored in a murine PCa tumor model. The results revealed that Exo manifested a circular or elliptical morphology, encapsulating a phospholipid bilayer approximately 100 nm in diameter. Notably, Exo readily infiltrated, with both Exo and miR-203-overexpressing Exo prompting macrophage polarization toward the M1 subtype. In the co-culture system, miR-203 exhibited pronounced suppression of LNCaP cell proliferation, migration, and invasion, while concurrently fostering apoptosis as compared with the LNCaP group (Control). In vivo experiments further disclosed that miR-203 greatly inhibited the growth of PCa tumors in nude mice. Markedly heightened expression of M1 macrophage markers such as IL-1β, IL-6, IL-12, CXCL9, and CXCL10 was observed within the tumor microenvironment following miR-203 intervention, as opposed to the model group. However, the introduction of miR-203 antagomir led to a reversal in tumor growth trends. This investigation indicates the presence of miR-203 within the urine of PCa patients and Exo originating from cells, and that miR-203 exerted antitumor effect by facilitating M1 macrophage polarization. Our study furnishes valuable insights into the potential applicability of miR-203 as a diagnostic biomarker and therapeutic target for PCa.

MicroRNAs in cancer metastasis: biological and therapeutic implications

Cancer metastasis is the primary cause of cancer-related deaths. The seeding of primary tumours at a secondary site is a highly inefficient process requiring substantial alterations in the genetic architecture of cancer cells. These alterations include significant changes in global gene expression patterns. MicroRNAs are small, non-protein coding RNAs which play a central role in regulating gene expression. Here, we focus on microRNA determinants of cancer metastasis and examine microRNA dysregulation in metastatic cancer cells. We dissect the metastatic process in a step-wise manner and summarise the involvement of microRNAs at each step. We also discuss the advantages and limitations of different microRNA-based strategies that have been used to target metastasis in pre-clinical models. Finally, we highlight current clinical trials that use microRNA-based therapies to target advanced or metastatic tumours.

Clinicopathological utility of miR-203a-3p in diagnosing colorectal cancer

BACKGROUND

Biomarkers, such as microRNAs, are helpful in diagnosing colorectal cancer, regulating disease progression, predicting disease recurrence, and determining therapy success. This research aimed to look at the clinicopathological characteristics of serum miRNA-203a-3p expression in colorectal cancer patients.

METHODS AND RESULTS

This case-control study was conducted on 43 patients with colorectal cancer and 43 healthy individuals. After RNA extraction, cDNA was synthesized. The expression of miR-203a-3p was measured using RT-qPCR. Demographic and histochemical data were extracted from patient documents. SPSS and GraphPad Prism software were used to analyze the data. The expression of miR-203a-3p in CRC patients was 2.39 times lower than in the control group (p < 0.0001). The miR-203a-3p expression was significantly lower in the CRC tumor stages, tumor grades, and lymph node metastasis compared to the control group (p < 0.0001 each). The ROC curves showed that the AUC was 0.73, and the best cut-point based on the Youden index was 0.3954, 0.7105, 0.5087, and 0.4868 for detecting colorectal cancer (p = 0.0002), tumor grade (p = 0.006), tumor stage (p = 0.001), and lymph node metastasis (p = 0.0011) compared to the control group, respectively. The binary logistic regression analysis was performed on the correlation between BMI, smoking, and cancer inheritance with miR-203a-3p in cancer and control groups.

CONCLUSION

This study's findings revealed that serum miR-203a-3p is a fair non-invasive molecular biomarker for diagnosing and progressing tumor grade, tumor stage, and lymph node metastasis in colorectal cancer. However, further research with higher statistical numbers is needed to strengthen the correlation and be used for diagnostic applications.

Transcriptome Profiling and Network Analysis Provide Insights Into the Pathogenesis of Vulvar Lichen Sclerosus

Vulvar lichen sclerosus (VLS) is a chronic inflammatory dermatosis that affects female anogenital skin. Although VLS is considered a T cell-mediated autoimmune disease, the diagnosis criteria, molecular mechanism, and universally accepted therapies for this disease remain largely unresolved. To explore disease pathogenesis and potential biomarkers, we performed an RNA-Seq-based transcriptome analysis to profile the gene expression of VLS lesions. Differentially expressed gene (DEG) analysis revealed profound changes in expressions of coding genes, microRNAs, and long non-coding RNAs. Pathway and network analysis suggested that T cell activation-associated genes, including CD3G, CD3D, CD8B, LAT, LCK, ZAP70, CCR5, CXCR3, CXCL9, CXCL10, and CXCL11, were highly expressed in VLS, while NR4A family genes (NR4A1, NR4A2, NR4A3), whose coding products inhibit T cell activity, were significantly downregulated, suggesting heightened T cell response in VLS. Neutrophil chemoattractant genes CXCL1, CXCL2, CXCL3, CXCL8, and their cognate receptor CXCR2 were downregulated, suggesting dampened neutrophil activity. We also found the downregulation of genes involved in cell cycle progression, including cyclins (CCNB1, CCNB2, CCNL1, CCNE1, and CCNK) and centrosome factors (CENPA, CENPE, CENPF, and CENPN), while microRNA-203a and let-7, microRNAs known to inhibit cell growth, were found to be upregulated. These data collectively indicate that cell proliferation in VLS is compromised. In sum, these findings comprehensively deciphered key regulatory genes and networks in VLS, which could further our understanding of disease mechanisms and point toward therapeutic strategies.

MicroRNAs and 'Sponging' Competitive Endogenous RNAs Dysregulated in Colorectal Cancer: Potential as Noninvasive Biomarkers and Therapeutic Targets

The gastrointestinal (GI) tract in mammals is comprised of dozens of cell types with varied functions, structures, and histological locations that respond in a myriad of ways to epigenetic and genetic factors, environmental cues, diet, and microbiota. The homeostatic functioning of these cells contained within this complex organ system has been shown to be highly regulated by the effect of microRNAs (miRNA). Multiple efforts have uncovered that these miRNAs are often tightly influential in either the suppression or overexpression of inflammatory, apoptotic, and differentiation-related genes and proteins in a variety of cell types in colorectal cancer (CRC). The early detection of CRC and other GI cancers can be difficult, attributable to the invasive nature of prophylactic colonoscopies. Additionally, the levels of miRNAs associated with CRC in biofluids can be contradictory and, therefore, must be considered in the context of other inhibiting competitive endogenous RNAs (ceRNA) such as lncRNAs and circRNAs. There is now a high demand for disease treatments and noninvasive screenings such as testing for bloodborne or fecal miRNAs and their inhibitors/targets. The breadth of this review encompasses current literature on well-established CRC-related miRNAs and the possibilities for their use as biomarkers in the diagnoses of this potentially fatal GI cancer.

Oncogenic Role of Exosomal Circular and Long Noncoding RNAs in Gastrointestinal Cancers

Circular RNAs (circRNAs) and long noncoding RNAs (lncRNAs) are differentially expressed in gastrointestinal cancers. These noncoding RNAs (ncRNAs) regulate a variety of cellular activities by physically interacting with microRNAs and proteins and altering their activity. It has also been suggested that exosomes encapsulate circRNAs and lncRNAs in cancer cells. Exosomes are then discharged into the extracellular environment, where they are taken up by other cells. As a result, exosomal ncRNA cargo is critical for cell-cell communication within the cancer microenvironment. Exosomal ncRNAs can regulate a range of events, such as angiogenesis, metastasis, immune evasion, drug resistance, and epithelial-to-mesenchymal transition. To set the groundwork for developing novel therapeutic strategies against gastrointestinal malignancies, a thorough understanding of circRNAs and lncRNAs is required. In this review, we discuss the function and intrinsic features of oncogenic circRNAs and lncRNAs that are enriched within exosomes.

Androgen receptor regulates eIF5A2 expression and promotes prostate cancer metastasis via EMT

Androgen receptor (AR) is an androgen-activated transcription factor of the nuclear receptor superfamily. AR plays a role in the development and progression of prostate cancer (PCa). However, the exact role of AR in PCa metastasis remains unclear. In the present study, we aimed to elucidate the function of AR in PCa. We found that eukaryotic translation initiation factor (EIF) 5A2, an elongation factor that induces epithelial-to-mesenchymal transition (EMT) in PCa cells, was significantly upregulated after 5α-dihydrotestosterone (DHT) stimulation and downregulated after anti‐androgen bicalutamide treatment in PCa cells with high AR expression, but not in cells with low AR expression. Moreover, eIF5A2 knockdown could eliminate DHT-induced invasion and migration of AR-positive PCa cells. DHT treatment decreased epithelial expression of E‐cadherin and β-catenin but increased the expression of the mesenchymal marker proteins Vimentin and N-cadherin. DHT therefore induced EMT, and knockdown of eIF5A2 inhibited DHT-induced EMT. Moreover, in vivo study, Luciferase signals from the lungs of the eIF5A2 plasmid group indicated higher metastasis ability, and the eIF5A2 siRNA group had lower metastasis ability. Our results suggest that AR positively regulates eIF5A2 expression in androgen-dependent cells, and stimulation of AR expression and signaling in prostate tumors promotes PCa metastasis by EMT induction and upregulation of eIF5A2.

The roles of microbial products in the development of colorectal cancer: a review

A large number of microbes exist in the gut and they have the ability to process and utilize ingested food. It has been reported that their products are involved in colorectal cancer development. The molecular mechanisms which underlie the relationship between gut microbial products and CRC are still not fully understood. The role of some microbial products in CRC is particularly controversial. Elucidating the effects of gut microbiota products on CRC and their possible mechanisms is vital for CRC prevention and treatment. In this review, recent studies are examined in order to describe the contribution metabolites and toxicants which are produced by gut microbes make to CRC, primarily focusing on the involved molecular mechanisms.Abbreviations: CRC: colorectal cancer; SCFAs: short chain fatty acids; HDAC: histone deacetylase; TCA cycle: tricarboxylic acid cycle; CoA: cytosolic acyl coenzyme A; SCAD: short chain acyl CoA dehydrogenase; HDAC: histone deacetylase; MiR-92a: microRNA-92a; KLF4: kruppel-like factor; PTEN: phosphatase and tensin homolog; PI3K: phosphoinositide 3-kinase; PIP2: phosphatidylinositol 4, 5-biphosphate; PIP3: phosphatidylinositol-3,4,5-triphosphate; Akt1: protein kinase B subtype α; ERK1/2: extracellular signal-regulated kinases 1/2; EMT: epithelial-to-mesenchymal transition; NEDD9: neural precursor cell expressed developmentally down-regulated9; CAS: Crk-associated substrate; JNK: c-Jun N-terminal kinase; PRMT1: protein arginine methyltransferase 1; UDCA: ursodeoxycholic acid; BA: bile acids; CA: cholic acid; CDCA: chenodeoxycholic acid; DCA: deoxycholic acid; LCA: lithocholic acid; CSCs: cancer stem cells; MHC: major histocompatibility; NF-κB: NF-kappaB; GPR: G protein-coupled receptors; ROS: reactive oxygen species; RNS: reactive nitrogen substances; BER: base excision repair; DNA: deoxyribonucleic acid; EGFR: epidermal growth factor receptor; MAPK: mitogen activated protein kinase; ERKs: extracellular signal regulated kinases; AKT: protein kinase B; PA: phosphatidic acid; TMAO: trimethylamine n-oxide; TMA: trimethylamine; FMO3: flavin-containing monooxygenase 3; H₂S: Hydrogen sulfide; SRB: sulfate-reducing bacteria; IBDs: inflammatory bowel diseases; NSAID: non-steroidal anti-inflammatory drugs; BFT: fragile bacteroides toxin; ETBF: enterotoxigenic fragile bacteroides; E-cadherin: extracellular domain of intercellular adhesive protein; CEC: colonic epithelial cells; SMOX: spermine oxidase; SMO: smoothened; Stat3: signal transducer and activator of transcription 3; Th17: T helper cell 17; IL17: interleukin 17; AA: amino acid; TCF: transcription factor; CDT: cytolethal distending toxin; PD-L1: programmed cell death 1 ligand 1.

miRNA-7062-5p Promoting Bone Resorption After Bone Metastasis of Colorectal Cancer Through Inhibiting GPR65

Bone metastasis is positively associated with a poor prognosis in patients with colorectal cancer (CRC). CRC always leads to osteolytic change, which is regulated by aberrant activation of osteoclasts. MicroRNAs are remarkedly involved in metastasis of CRC; however, their role in bone metastasis of CRC is still unclear. The aim of this study is to find key microRNAs that are critical to bone resorption in bone metastasis of CRC. In this study, bone metastasis model was established through intratibially injecting CT-26 cells or MC-38 cells. Tartrate-resistant acid phosphatase (TRAP) staining was performed to explore the osteoclastogenesis of primary early osteoclast precursors (OCPs) after stimulation by CT-26 conditioned medium (CM). Then, microarray assay was performed to find differentially expressed miRNAs and mRNAs. The target gene of miRNA was confirmed by dual-luciferase analysis. The effect of miRNA, its target gene on osteoclastogenesis, and involved pathways were explored by Western blot, immunofluorescence analysis, and TRAP staining. Finally, the effect of miRNA on bone resorption in vivo was observed. miRNA-7062-5p was upregulated in early OCPs cultured in CT-26 CM or MC-38 CM. GPR65 was proven to be the target gene of miRNA-7062-5p. Overexpression of GPR65 can rescue the osteoclastogenesis caused by miRNA-7062-5p through activation of AMPK pathway. Local injection of miRNA-7062-5p inhibitors efficiently improved the bone resorption. Our study found the role of miRNA-7062-5p in regulating osteoclast formation, and our findings provided a potential therapeutic target in treatment of bone metastasis of CRC.

microRNA Prognostic Signature for Postoperative Success of Metastatic Orthopedic Cancers: Implications for Precision Microsurgery

The importance of miRNA prognostic signature in cancer, particular cancer metastasis is increasingly being realized. Bone metastasis from several primary human cancers can be managed in clinics by surgical intervention but the prognostic impact of miRNA signature on post-surgery outcome of patients is unknown. This study evaluated a miRNA signature for post-operative outcome of patients with bone metastatic disease. First, the miRNAs, miR-135, miR-203, miR-10b, miR-194, miR-886, and miR-124 were evaluated in bone metastatic tissues, relative to adjacent control tissue. The cohorts of samples (n = 44) consisted of bone metastatic cancer patients with primary lung (n = 18) or breast cancer (n = 26). miR-203 was significantly down-regulated while miR-10b was significantly up-regulated in bone metastasis. Additionally, miR-135 was significantly differentially expressed in the primary lung cancer patients while miR-194 in primary breast cancer patients. The low miR-203- high miR-10b expression was designated high risk group and, compared to the low risk group (high miR-203-low miR-10b expression). Patients with the signature high risk fared significantly better with surgical intervention, in terms of survival at 12 months time point (40% survival with surgery vs. 10% survival without surgery), as revealed by retrospective analysis of patient data. This work reveals potential utilization of miRNA expression levels in not only the general prognosis of cancer metastasis but also the prognosis of surgical intervention with implication for better stratification of patients.

Impact of miRNAs expression modulation on the methylation status of breast cancer stem cell-related genes

PURPOSE

Altered miRNAs play a crucial role in the emergence of the breast cancer stem cell (BCSC) phenotype. The interplay between miRNAs and methylation enzymes has been documented. One of the most aggressive breast cancer cell lines, MDA-MB-231, has expressed much more DNMT3B than DNMT3A. This study aims to evaluate the ability of miR-203 restoration and miR-150 inhibition to regulate DNMT3B and DNMT3A to modify the methylation level of BCSC-associated genes.

METHODS

MDA-MB-231 cells were transfected with miR-203 mimic or miR-150 inhibitor or DNMT3B siRNA, and downstream analysis was performed by flow cytometry, real-time PCR and Western blotting.

RESULTS

DNMT3A and DNMT3B are regulated both by miR-203a-3p and miR-150-5p. Transfection with miR-203 mimic and miR-150 inhibitor significantly reduced the CD44+CD24- subpopulation and down-regulated the expression of CD44 mRNA by increasing promoter methylation levels. SiRNA knockdown of DNMT3B increased the CD44+CD24- subpopulation and the expression of CD44 and ALDH1A3 by decreasing methylation density. The inhibition of miR-150 down-regulated OCT3/4 and SOX2 expression without affecting methylation levels, while miR-203 restoration and miR-150 inhibition down-regulated NANOG expression by elevating the methylation level. A positive-feedback loop was found between miR-203 and its target DNMT3B, as restoring miR-203 suppressed DNMT3B, while knocking down DNMT3B up-regulated miR-203. The restoration of miR-203 and knockdown of DNMT3B decreased methylation levels and increased the expression of miR-141 and miR-200c.

CONCLUSIONS

The study concluded that miR-203 and miR-150 play a role in the regulation of genes involved in BCSC methylation, including other miRNAs, by targeting DNMT3B and DNMT3A.

miRNA Clusters with Up-Regulated Expression in Colorectal Cancer

Simple Summary

As miRNAs show the capacity to be used as CRC biomarkers, we analysed experimentally validated data about frequently up-regulated miRNA clusters in CRC tissue. We identified 15 clusters that showed increased expression in CRC: miR-106a/363, miR-106b/93/25, miR-17/92a-1, miR-181a-1/181b-1, miR-181a-2/181b-2, miR-181c/181d, miR-183/96/182, miR-191/425, miR-200c/141, miR-203a/203b, miR-222/221, mir-23a/27a/24-2, mir-29b-1/29a, mir-301b/130b and mir-452/224. Cluster positions in the genome are intronic or intergenic. Most clusters are regulated by several transcription factors, and by long non-coding RNAs. In some cases, co-expression of miRNA with other cluster members or host gene has been proven. miRNA expression patterns in cancer tissue, blood and faeces were compared. The members of the selected clusters target 181 genes. Their functions and corresponding pathways were revealed with the use of Panther analysis. Clusters miR-17/92a-1, miR-106a/363, miR-106b/93/25 and miR-183/96/182 showed the strongest association with metastasis occurrence and poor patient survival, implicating them as the most promising targets of translational research.

Abstract

Colorectal cancer (CRC) is one of the most common malignancies in Europe and North America. Early diagnosis is a key feature of efficient CRC treatment. As miRNAs can be used as CRC biomarkers, the aim of the present study was to analyse experimentally validated data on frequently up-regulated miRNA clusters in CRC tissue and investigate their members with respect to clinicopathological characteristics of patients. Based on available data, 15 up-regulated clusters, miR-106a/363, miR-106b/93/25, miR-17/92a-1, miR-181a-1/181b-1, miR-181a-2/181b-2, miR-181c/181d, miR-183/96/182, miR-191/425, miR-200c/141, miR-203a/203b, miR-222/221, mir-23a/27a/24-2, mir-29b-1/29a, mir-301b/130b and mir-452/224, were selected. The positions of such clusters in the genome can be intronic or intergenic. Most clusters are regulated by several transcription factors, and miRNAs are also sponged by specific long non-coding RNAs. In some cases, co-expression of miRNA with other cluster members or host gene has been proven. miRNA expression patterns in cancer tissue, blood and faeces were compared. Based on experimental evidence, 181 target genes of selected clusters were identified. Panther analysis was used to reveal the functions of the target genes and their corresponding pathways. Clusters miR-17/92a-1, miR-106a/363, miR-106b/93/25 and miR-183/96/182 showed the strongest association with metastasis occurrence and poor patient survival, implicating them as the most promising targets of translational research.

Long non-coding RNA TP73-AS1 promotes pancreatic cancer growth and metastasis through miRNA-128-3p/GOLM1 axis

BACKGROUND

Previous studies have suggested that long non-coding RNAs (lncRNA) TP73-AS1 is significantly upregulated in several cancers. However, the biological role and clinical significance of TP73-AS1 in pancreatic cancer (PC) remain unclear.

AIM

To investigate the role of TP73-AS1 in the growth and metastasis of PC.

METHODS

The expression of lncRNA TP73-AS1, miR-128-3p, and GOLM1 in PC tissues and cells was detected by quantitative real-time polymerase chain reaction. The bioinformatics prediction software ENCORI was used to predict the putative binding sites of miR-128-3p. The regulatory roles of TP73-AS1 and miR-128-3p in cell proliferation, migration, and invasion abilities were verified by Cell Counting Kit-8, wound-healing, and transwell assays, as well as flow cytometry and Western blot analysis. The interactions among TP73-AS1, miR-128-3p, and GOLM1 were explored by bioinformatics prediction, luciferase assay, and Western blot.

RESULTS

The expression of TP73-AS1 and miRNA-128-3p was dysregulated in PC tissues and cells. High TP73-AS1 expression was correlated with a poor prognosis. TP73-AS1 silencing inhibited PC cell proliferation, migration, and invasion in vitro as well as suppressed tumor growth in vivo. Mechanistically, TP73-AS1 was validated to promote PC progression through GOLM1 upregulation by competitively binding to miR-128-3p.

CONCLUSION

Our results demonstrated that TP73-AS1 promotes PC progression by regulating the miR-128-3p/GOLM1 axis, which might provide a potential treatment strategy for patients with PC.

Role of mir-33a, mir-203b, mir361-3p, and mir-424 in hepatocellular carcinoma

Background/aim

Hepatocellular carcinoma (HCC) is one of the most aggressive cancer types. MicroRNAs (miRNAs) are small noncoding regulatory RNAs that function posttranscriptionally. miRNA deregulation was observed in the development and progression of HCC. In this study, we aimed to investigate the expression levels of four miRNAs (mir-33a, mir-203b, mir361-3p, and mir-424) in HCC patients in comparison to healthy individuals.

Materials and methods

Venous blood samples were collected from both HCC patients and healthy individuals. In order to determine the relative expression levels of mir-33a, mir-203b, mir361-3p, and hsa-mir-424 in HCC patients, probe-based quantitative real time PCR (qRT-PCR) was performed. The cycle threshold (Ct) results were analyzed according to the 2−∆∆Ct method and statistical analyses were performed by SPSS Statistics version 15 for Windows.

Results

qRT-PCR analysis revealed that the expression levels of mir-33a (fold change: 7.3 and P < 0.001), mir-203b (fold change: 4.6 and P < 0.001), and mir361-3p (fold change: 5.1 and P < 0.001)were downregulated compared to healthy individuals and mir-424 did not show any significant change between HCC patients and controls.

Conclusion

Our results indicated that mir-33a, mir-203b, and mir-361-3p may significantly contribute to tumor pathogenesis in HCC and have potential to be used as a noninvasive biomarker for cancer therapy.

miR-203a suppresses cell proliferation by targeting RING-finger protein 6 in colorectal cancer

Colorectal cancer (CRC) is one of most common cancers worldwide. Although miR-203a is reported as a tumor suppressor involved in cell progression in some cancers, the role of miR-203a in CRC is still controversial and the underling mechanism of miR-203a in CRC remains unclear. Here, we demonstrated that low expression of miR-203a had poorer survival in CRC patients. miR-203a was down-regulated in most human colon cancer cells. Overexpression of miR-203a could inhibit colon cancer cell proliferation and arrest cell cycle in G1 phase. Bioinformatics and dual luciferase reporter assay confirmed that RING-finger protein 6 (RNF6) was a target gene of miR-203a. Silencing RNF6 inhibited cell proliferation and arrest cell cycle in G1 phase. RNF6 overexpression reversed the effects of miR-203a overexpression in colon cancer cells. Taken together, our data indicate that miR-203a inhibits colon cancer cell proliferation by targeting RNF6, offer novel insights into the regulatory network of miR-203a-modulated cell cycle and proliferation, and suggest that miR-203a a potential therapeutic target in CRC treatment.

Circulating miRNA as Biomarkers for Colorectal Cancer Diagnosis and Liver Metastasis

Colorectal cancer (CRC) is the second leading cause of cancer deaths worldwide. Stage IV CRC patients have poor prognosis with a five-year survival rate of 14%. Liver metastasis is the main cause of mortality in CRC patients. Since current screening tests have several drawbacks, effective stable non-invasive biomarkers such as microRNA (miRNA) are needed. We aim to investigate the expression of miRNA (miR-21, miR-19a, miR-23a, miR-29a, miR-145, miR-203, miR-155, miR-210, miR-31, and miR-345) in the plasma of 62 Lebanese Stage IV CRC patients and 44 healthy subjects using RT-qPCR, as well as to evaluate their potential for diagnosis of advanced CRC and its liver metastasis using the Receiver Operating Characteristics (ROC) curve. miR-21, miR-145, miR-203, miR-155, miR-210, miR-31, and miR-345 were significantly upregulated in the plasma of surgery naïve CRC patients when compared to healthy individuals. We identified two panels of miRNA that could be used for diagnosis of Stage IV CRC (miR-21 and miR-210) with an area under the curve (AUC) of 0.731 and diagnostic accuracy of 69% and liver metastasis (miR-210 and miR-203) with an AUC = 0.833 and diagnostic accuracy of 72%. Panels of specific circulating miRNA, which require further validation, could be potential non-invasive diagnostic biomarkers for CRC and liver metastasis.

The miR-203a Regulatory Network Affects the Proliferation of Chronic Myeloid Leukemia K562 Cells

To study the molecular mechanism by which miR-203a affects the development of CML, bioinformatics software was used to predict the upstream transcription factors and downstream target genes of miR-203a. A 5’-rapid amplification of cDNA ends assay was performed to detect gene transcription initiation sites. A chromatin immunoprecipitation assay was used to verify the binding of transcription factors and promoter regions. A double luciferase reporter gene vector was constructed to demonstrate the regulatory effect of miR-203a on target genes. Real-time PCR and western blotting were used to detect the relative expression levels of genes and proteins, respectively. The results showed that there was a binding site for the transcription factor EGR1 in the upstream promoter region of miR-203a. WT1, BMI1, and XIAP were identified as target genes regulated by miR-203a. EGR1 and miR-203a were downregulated in human peripheral blood mononuclear cells and the CML K562 cell line, while WT1, BMI1, and XIAP were upregulated. The transcription initiation site of miR-203a was identified in the upstream promoter region (G nucleotide at −339 bp), and the transcription factor EGR1 could bind to the promoter region (at −268 bp) of miR-203a and increase its expression. Over expression of miR-203a inhibited the proliferation of K562 cells. A rescue assay showed that overexpression of WT1, BMI1, and XIAP offset the antitumor effect of miR-203a. Conclusion, EGR1 positively regulated the expression of miR-203a, thus relieving the inhibition of miR-203a on the translation of its target genes (WT1, BMI1, and XIAP) and affecting the proliferation of K562 cells.

Portrait of Cancer Stem Cells on Colorectal Cancer: Molecular Biomarkers, Signaling Pathways and miRNAome

Colorectal cancer (CRC) is a leading cause of cancer death worldwide, and about 20% is metastatic at diagnosis and untreatable. Increasing evidence suggests that the heterogeneous nature of CRC is related to colorectal cancer stem cells (CCSCs), a small cells population with stemness behaviors and responsible for tumor progression, recurrence, and therapy resistance. Growing knowledge of stem cells (SCs) biology has rapidly improved uncovering the molecular mechanisms and possible crosstalk/feedback loops between signaling pathways that directly influence intestinal homeostasis and tumorigenesis. The generation of CCSCs is probably connected to genetic changes in members of signaling pathways, which control self-renewal and pluripotency in SCs and then establish function and phenotype of CCSCs. Particularly, various deregulated CCSC-related miRNAs have been reported to modulate stemness features, controlling CCSCs functions such as regulation of cell cycle genes expression, epithelial-mesenchymal transition, metastasization, and drug-resistance mechanisms. Primarily, CCSC-related miRNAs work by regulating mainly signal pathways known to be involved in CCSCs biology. This review intends to summarize the epigenetic findings linked to miRNAome in the maintenance and regulation of CCSCs, including their relationships with different signaling pathways, which should help to identify specific diagnostic, prognostic, and predictive biomarkers for CRC, but also develop innovative CCSCs-targeted therapies.

The potential value of miRNA-223 as a diagnostic biomarker for Egyptian colorectal patients

OBJECTIVES

Colorectal cancer (CRC) is the third lethal malignancy worldwide. Dysregulation of microRNAs (miRNAs) mediates several growth factors signaling pathways and induces abnormal genes expression, which leads to colorectal carcinogenesis. We aimed to comprehensively assess the expression of miRNA-200c, miRNA-203a, miRNA-223 in Egyptian CRC tissue and their corresponding serum samples and to explore if they have any potential prognostic or diagnostic value for CRC patients.

METHODS

A total of 195 subjects (120 CRC patients and 75 healthy controls) participated in exploration and validation sets. The relative expression of miRNA-200c, miRNA-203a, and miRNA-223 was measured in both CRC tissue and serum samples, and the expressed miRNAs were compared in different CRC grades and types and the prognostic value was evaluated.

RESULTS

The expression levels of miRNA-200c and miRNA-203a were reduced in CRC tissue samples than adjacent noncancerous tissues. miRNA-223 level was significantly upregulated in both CRC tissue and serum samples with a positive association between them (r = 0.85, P = 0.001). The miRNA-223 can effectively discriminate CRC patients from controls and can significantly differentiate between colon and rectal cancer patients. The association between serum miRNA-223 expression and CRC development was validated in the second set and the ROC curve showed highly significant prognostic value with 90.1% sensitivity, 87% specificity, and area under the curve of 0.914 (95% confidence interval: 0.830-0.978, P = 0.0001). These results showed the association between miRNA-223 upregulation and the CRC carcinogenesis.

CONCLUSION

Circulating miRNA-223 can be a potential noninvasive prognostic biomarker for Egyptian CRC patients.

Correlation between lncRNA SNHG16 gene polymorphism and its interaction with environmental factors and susceptibility to colorectal cancer

OBJECTIVE

To study the relationship between long-chain non-coding RNA small nucleolar RNA host gene 16 (lncRNA SNHG16) polymorphisms and its interaction with environmental factors and susceptibility to colorectal cancer (CRC).

METHODS

Sanger sequencing was used to analyze genotypes of lncRNA SNHG16 gene rs7353, rs8038, and rs15278 sites. Multifactor dimensionality reduction was used to analyze interactions between lncRNA SNHG16 gene rs7353, rs8038, rs15278 sites, and environmental factors. Haploview 4.1 software was used to analyze linkage disequilibrium of lncRNA SNHG16 gene rs7353, rs8038, and rs15278 sites. Quantitative real-time polymerase chain reaction was used to analyze plasma lncRNA SNHG16 levels of CRC patients and control subjects.

RESULTS

Variation of the lncRNA SNHG16 gene rs7353 site A>G variation was associated with decreased CRC susceptibility (Odds ratio [OR] = 0.50, 95% confidence interval [CI]: 0.40-0.62, P < .01). The rs8038 site G>A and rs15278 site A>G variation were associated with increased CRC susceptibility (OR = 1.87, 95% CI: 1.47-2.36, P < .01). The rs15278 site G>A variation was associated with increased CRC susceptibility (OR = 2.24, 95% CI: 1.61-3.11, P < .01). Interaction combinations featuring age, rs7353, rs8038, and rs15278 single nucleotide polymorphism are 13.53 times more susceptible to CRC than other interactions (95% CI: 9.43-19.41, P < .01). The rs15278, rs8038, and rs7353 site AGA haplotypes were significantly associated with a decreased CRC risk (OR = 0.65, 95% CI: 0.48-0.88, P = .01), AAG haplotypes were significantly associated with an increased CRC risk (OR = 2.00, 95% CI: 1.27-3.17, P < .01). High lncRNA SNHG16 expression was associated with tumor progression in CRC patients (χ = 8.85, P = .03). The rs7353 site A>G variation caused a significant decrease in plasma lncRNA SNHG16 level (P < .01), while the rs8038 site G>A variation and rs15278 site A>G variation resulted in increased plasma lncRNA SNHG16 levels.

CONCLUSION

Polymorphisms of lncRNA SNHG16 gene rs7353, rs8038, rs15278 loci and their interaction with age are significantly associated with CRC susceptibility.

Biomarker exploration of microRNA-203 as a promising substrate for predicting poor survival outcome in colorectal cancer

Background

Increasing studies indicated that microRNA-203 (miR-203) may play an important part in the prognosis of CRC. Nevertheless, the prognostic and influential mechanism of miR-203 expression in CRC remains to be inconclusive. Accordingly, we conducted the current study to investigate the biomarker performance of miR-203 in CRC.

Methods

In the present study, we conducted an evidence synthesis of the published literatures to identify the prognostic roles of miR-203 in patients with CRC. Moreover, several bioinformatics methods were applied for exploring the biomarker roles of miR-203.

Results

It was demonstrated that elevated miR-203 expression was clearly related to worse overall survival (HR: 1.55, 95% CI: 1.07–2.24, P = 0.021) for CRC. The gene Ontology (GO) analysis indicated that miR-203 targets were primarily involved in a series of GO items closely associated with the molecular pathogenesis of CRC. The pathway analysis exhibited the potential signal pathways of miR-203 involved in CRC including pathways in cancer, wnt pathway, prolactin signaling pathway, proteoglycans in cancer, FoxO pathway, focal adhesion and Ras pathway. By constructing a protein-protein interaction (PPI) network of the targets of miR-203, ten crucial proteins and a significant network module were retrieved and found to serve important roles in the molecular pathogenesis of CRC.

Conclusions

Our results indicated that miR-203 may function as a promising biomarker to monitor CRC survival outcomes and progression. Notably, large-scale prospective cohort studies and biological experiments are required to confirm our conclusions.

miRNA profiling of primate cervicovaginal lavage and extracellular vesicles reveals miR-186-5p as a potential antiretroviral factor in macrophages

Cervicovaginal secretions, or their components collected, are referred to as cervicovaginal lavage (CVL). CVL constituents have utility as biomarkers and play protective roles in wound healing and against HIV-1 infection. However, several components of cervicovaginal fluids are less well understood, such as extracellular RNAs and their carriers, for example, extracellular vesicles (EVs). EVs comprise a wide array of double-leaflet membrane extracellular particles and range in diameter from 30 nm to over one micron. The aim of this study was to determine whether differentially regulated CVL microRNAs (miRNAs) might influence retrovirus replication. To this end, we characterized EVs and miRNAs of primate CVL during the menstrual cycle and simian immunodeficiency virus (SIV) infection of macaques. EVs were enriched by stepped ultracentrifugation, and miRNA profiles were assessed with a medium-throughput stem-loop/hydrolysis probe qPCR platform. Whereas hormone cycling was abnormal in infected subjects, EV concentration correlated with progesterone concentration in uninfected subjects. miRNAs were present predominantly in the EV-depleted CVL supernatant. Only a small number of CVL miRNAs changed during the menstrual cycle or SIV infection, for example, miR-186-5p, which was depleted in retroviral infection. This miRNA inhibited HIV replication in infected macrophages in vitro. In silico target prediction and pathway enrichment analyses shed light on the probable functions of miR-186-5p in hindering HIV infections via immunoregulation, T-cell regulation, disruption of viral pathways, etc. These results provide further evidence for the potential of EVs and small RNAs as biomarkers or effectors of disease processes in the reproductive tract.

Eukaryotic translation initiation factor 5A in the pathogenesis of cancers

Cancer is the leading cause of death worldwide. The absence of obvious symptoms and insufficiently sensitive biomarkers in early stages of carcinoma limits early diagnosis. Cancer therapy agents and targeted therapy have been used extensively against tissues or organs of specific cancers. However, the intrinsic and/or acquired resistance to the agents or targeted drugs as well as the serious toxic side effects of the drugs would limit their use. Therefore, identifying biomarkers involved in tumorigenesis and progression represents a challenge for cancer diagnosis and therapeutic strategy development. The eukaryotic translation factor 5A (eIF5A), originally identified as an initiation factor, was later shown to promote translation elongation of iterated proline sequences. There are two eIF5A isoforms (eIF5A1 and eIF5A2). eIF5A2 protein consists of 153 residues, and shares 84% amino acid identity with eIF5A1. However, the biological functions of these two isoforms may be significantly different. Recently, it was demonstrated that eIF5Ais widely involved in the pathogenesis of a number of diseases, including cancers. In particular, eIF5A plays an important role in regulating tumor growth, invasion, metastasis and tumor microenvironment. It was also shown to serve as a potential biomarker and target for the diagnosis and treatment of cancers. The present review briefly discusses the latest findings of eIF5A in the pathogenesis of certain malignant cancers and evolving clinical applications.

Roles of miRNAs in Colorectal Cancer: Therapeutic Implications and Clinical Opportunities

Colorectal cancer (CRC) is one of the most disseminated diseases across the globe engaging the digestive system. Various therapeutic methods from traditional to the state-of-the-art ones have been applied in CRC patients, however, the attempts have been unfortunate to lead to a definite cure. MiRNAs are a smart group of non-coding RNAs having the capabilities of regulating and controlling coding genes. By utilizing this stock-in-trade biomolecules, not only disease’s symptoms can be eliminated, there may also be a good chance for the complete cure of the disease in the near future. Herein, we provide a comprehensive review delineating the therapeutic relationship between miRNAs and CRC. To this, various clinical aspects of miRNAs which act as a tumor suppressor and/or an oncogene, their underlying cellular processes and clinical outcomes, and, in particular, their effects and expression level changes in patients treated with chemo- and radiotherapy are discussed. Finally, based on the results deducted from scientific research studies, therapeutic opportunities based on targeting/utilizing miRNAs in the preclinical as well as clinical settings are highlighted.

Inflammatory Breast Carcinoma: Elevated microRNA miR-181b-5p and Reduced miR-200b-3p, miR-200c-3p, and miR-203a-3p Expression as Potential Biomarkers with Diagnostic Value

Inflammatory breast cancer (IBC) is a rare yet aggressive breast cancer variant, associated with a poor prognosis. The major challenge for IBC is misdiagnosis due to the lack of molecular biomarkers. We profiled dysregulated expression of microRNAs (miRNAs) in primary samples of IBC and non-IBC tumors using human breast cancer miRNA PCR array. We discovered that 28 miRNAs were dysregulated (10 were upregulated, while 18 were underexpressed) in IBC vs. non-IBC tumors. We identified 128 hub genes, which are putative targets of the differentially expressed miRNAs and modulate important cancer biological processes. Furthermore, our qPCR analysis independently verified a significantly upregulated expression of miR-181b-5p, whereas a significant downregulation of miR-200b-3p, miR-200c-3p, and miR-203a-3p was detected in IBC tumors. Receiver operating characteristic (ROC) curves implied that the four miRNAs individually had a diagnostic accuracy in discriminating patients with IBC from non-IBC and that miR-203a-3p had the highest diagnostic value with an AUC of 0.821. Interestingly, a combination of miR-181b-5p, miR-200b-3p, and miR-200c-3p robustly improved the diagnostic accuracy, with an area under the curve (AUC) of 0.897. Intriguingly, qPCR revealed that the expression of zinc finger E box-binding homeobox 2 (ZEB2) mRNA, the putative target of miR-200b-3p, miR-200c-3p, and miR-203a-3p, was upregulated in IBC tumors. Overall, this study identified a set of miRNAs serving as potential biomarkers with diagnostic relevance for IBC.

Finding new cancer epigenetic and genetic biomarkers from cell-free DNA by combining SALP-seq and machine learning

The effective non-invasive diagnosis and prognosis are critical for cancer treatment. The plasma cell-free DNA (cfDNA) provides a good material for cancer liquid biopsy and its worth in this field is increasingly explored. Here we describe a new pipeline for effectively finding new cfDNA-based biomarkers for cancers by combining SALP-seq and machine learning. Using the pipeline, 30 cfDNA samples from 26 esophageal cancer (ESCA) patients and 4 healthy people were analyzed as an example. As a result, 103 epigenetic markers (including 54 genome-wide and 49 promoter markers) and 37 genetic markers were identified for this cancer. These markers provide new biomarkers for ESCA diagnosis, prognosis and therapy. Importantly, these markers, especially epigenetic markers, not only shed important new insights on the regulatory mechanisms of this cancer, but also could be used to classify the cfDNA samples. We therefore developed a new pipeline for effectively finding new cfDNA-based biomarkers for cancers by combining SALP-seq and machine learning. In this study, we also discovered new clinical worth of cfDNA distinct from other reported characters.

LINC00657 promotes colorectal cancer stem-like cell invasion by functioning as a miR-203a sponge

Recently, the role of long non-coding RNAs (lncRNAs) in regulating multiple cancer types has attracted increasing interest because of their involvement in cell metastasis in different cancer types. Previous studies indicated that LINC00657 may work as an oncogene in gastric and colon cancer. However, the functional role and mechanistic action of LINC00657 on colorectal cancer (CRC) remains unknown. Therefore, in this study, the role of LINC00657 in CRC was evaluated. Our results showed that LINC00657 was enriched in CRC stem-like cells (CSCs) and significantly promoted CSCs invasion ability. LINC00657 expression resulted frequently up-regulated in CRC patient tissue, and high expression of LINC00657 was correlated with an advanced clinical stage, lymph node metastasis, distant metastasis and poor overall survival of CRC patients. Furthermore, LINC00657 worked as a competing endogenous RNA (ceRNA) for miR-203a, antagonizing its function as a tumor suppressor and leading to the de-repression of CSCs invasion. Collectively, our observations revealed that LINC00657 is involved in CRC invasion by acting as a competing endogenous RNA. Thus, LINC00657 may serve as a potential prognostic factor and/or therapeutic target for CRC.

LncRNA FTX Contributes to the Progression of Colorectal Cancer Through Regulating miR-192-5p/EIF5A2 Axis

Background

Long non-coding RAN five prime to Xist (LncRNA FTX) has been revealed to be a cancer-related lncRNA and implicated in the progression of colorectal cancer (CRC). Besides, miR-192-5p (miR-192) or eukaryotic initiation factor 5A2 (EIF5A2) also was identified to link with the tumorigenesis of CRC. Here, we further explored the function of FTX and the regulatory relationship among FTX, miR-192 and EIF5A2 in CRC progression.

Methods

Levels of FTX, miR-192-5p and EIF5A2 were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or Western blot, respectively. Cell proliferation, apoptosis, migration and invasion were analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry or transwell assay, respectively. The interaction between miR-192-5p and FTX or EIF5A2 was confirmed by dual-luciferase reporter and pull-down assay. Murine xenograft model was established using LoVo cells transfected with sh-FTX.

Results

FTX was up-regulated in CRC tissues and cell lines, knockdown of FTX inhibited CRC cell proliferation, migration and invasion in vitro as well as suppressed CRC tumor growth in vivo. FTX was confirmed to directly bind to miR-192-5p and negatively regulated miR-192-5p expression in CRC cells. Besides that overexpressed FTX positively modulated EIF5A2, a direct target of miR-192-5p, via miR-192-5p in CRC cells. Importantly, the inhibitory activities on CRC progression mediated by FTX deletion were reversed miR-192-5p down-regulation or EIF5A2 up-regulation.

Conclusion

LncRNA FTX functioned as an oncogene to contribute to CRC progression by regulating miR-192-5p/EIF5A2 axis, providing a novel insight into the pathogenesis of CRC and a promising therapeutic target for CRC treatment.

Identification of novel functional CpG-SNPs associated with type 2 diabetes and coronary artery disease

Genome-wide association studies (GWASs) have identified hundreds of single nucleotide polymorphisms (SNPs) associated with type 2 diabetes (T2D) and coronary artery disease (CAD), respectively. Nevertheless, these studies were generally performed for single-trait/disease and failed to assess the pleiotropic role of the identified variants. To identify novel functional loci and the pleiotropic relationship between CAD and T2D, the targeted cFDR analysis on CpG-SNPs was performed by integrating two independent large and multi-centered GWASs with summary statistics of T2D (26,676 cases and 132,532 controls) and CAD (60,801 cases and 123,504 controls). Applying the cFDR significance threshold of 0.05, we observed a pleiotropic enrichment between T2D and CAD by incorporating pleiotropic effects into a conditional analysis framework. We identified 79 novel CpG-SNPs for T2D, 61 novel CpG-SNPs for CAD, and 18 novel pleiotropic loci for both traits. Among these novel CpG-SNPs, 33 of them were annotated as methylation quantitative trait locus (meQTL) in whole blood, and ten of them showed expression QTL (eQTL), meQTL, and metabolic QTL (metaQTL) effects simultaneously. To the best of our knowledge, we performed the first targeted cFDR analysis on CpG-SNPs, and our findings provided novel insights into the shared biological mechanisms and overlapped genetic heritability between T2D and CAD.

Downregulation of lung miR-203a-3p expression by high-altitude hypoxia enhances VEGF/Notch signaling

Hypoxia-related microRNAs (miRNAs) are involved in the pathogenesis of various diseases. Because potential variations in miRNA expression mediated by hypoxic lung injury at high altitude remain incompletely characterized, we used a rat model to investigate the biochemical and miRNA changes induced by high-altitude hypoxia. After 24, 48, or 72 h of hypoxic exposure, expression of VEGF/Notch pathway-related proteins were increased in rat lung tissues. Microarray screening of hypoxic lung samples revealed 57 differentially expressed miRNAs, 19 of which were related to the VEGF/Notch signaling pathway. We verified that the top downregulated miRNA (miR-203a-3p) suppresses VEGF-A translation through direct binding and also indirectly reduces Notch1, VEGFR2, and Hes1 levels, which restricts the angiogenic capacity of pulmonary microvascular endothelial cells in vitro. These findings may aid in the development of new therapeutic strategies for the prevention and treatment of hypoxic lung injury at high altitude.

Recent insights into eukaryotic translation initiation factors 5A1 and 5A2 and their roles in human health and disease

The eukaryotic translation initiation factor 5A1 (eIF5A1) and its homolog eIF5A2 are the only two human proteins containing the unique post-translational modification-hypusination, which is essential for the function of these two proteins. eIF5A1 was initially identified as a translation initiation factor by promoting the first peptide bond formation of protein during translation; however, recent results suggest that eIF5A1 also functions as a translation elongation factor. It has been shown that eIF5A1 is implicated in certain human diseases, including diabetes, several human cancer types, viral infections and diseases of neural system. Meanwhile, eIF5A2 is overexpressed in many cancers, and plays an important role in the development and progression of cancers. As multiple roles of these two factors were observed among these studies, therefore, it remains unclear whether they act as oncogene or tumor suppressor. In this review, the recent literature of eIF5As and their roles in human diseases, especially in human cancers, will be discussed.

MicroRNAs and Metastasis

Metastasis, the development of secondary malignant growths at a distance from the primary site of a cancer, is associated with almost 90% of all cancer deaths, and half of all cancer patients present with some form of metastasis at the time of diagnosis. Consequently, there is a clear clinical need for a better understanding of metastasis. The role of miRNAs in the metastatic process is beginning to be explored. However, much is still to be understood. In this review, we present the accumulating evidence for the importance of miRNAs in metastasis as key regulators of this hallmark of cancer.

MiR-486-5p Suppresses Proliferation and Migration of Hepatocellular Carcinoma Cells through Downregulation of the E3 Ubiquitin Ligase CBL

MicroRNAs have been broadly implicated in cancer, but precise functions and mechanisms in carcinogenesis vary among cancer types and in many cases remain poorly understood. Hepatocellular carcinoma (HCC) is among the most frequent and lethal cancers. The aim of the present study was to investigate the role of miR-486-5p in HCC and identify its specific target. MiR-486-5p was significantly downregulated in HCC tissues and cell lines compared with noncancerous tissues and, respectively, although expression level was not correlated with the degree of infiltration or tumor stage. However, miR-486-5p overexpression in HCC cells inhibited proliferation and migration as evidenced by CCK-8 cell counting, wound healing, and transwell assays, indicating that miR-486-5p is an HCC suppressor. We employed four miRNA databases to predict the target genes of miR-486-5p and verified retrieved genes using qPCR and western blotting. The E3 ubiquitin ligase CBL was significantly downregulated by miR-486-5p overexpression in HCC cell lines at both mRNA and protein level, and overexpression of CBL counteracted the inhibitory effects of miR-486-5p on HCC cell proliferation and migration. Moreover, CBL expression was negatively correlated with miR-486-5p expression in HCC tissues. Collectively, our results suggest that miR-486-5p may act as a tumor suppressor gene in HCC by downregulating CBL expression.

Long Noncoding RNA TP73-AS1 Modulates Medulloblastoma Progression In Vitro And In Vivo By Sponging miR-494-3p And Targeting EIF5A2

Background

Previous studies have shown that P73 antisense RNA 1T (non-protein coding), also known as TP73-AS1, is a long non-coding RNA (lncRNA) and involved in the development of medulloblastoma. However, the regulatory mechanism of lncRNA TP73-AS1 in medulloblastoma was still unclear, the present study was aimed to investigate the detailed functions and the mechanism of TP73-AS1 in regulation of medulloblastoma.

Materials and methods

The levels of TP73-AS1, miR-494-3p, and Eukaryotic initiation factor 5A2 (EIF5A2) were determined using quantitative real-time PCR (qRT-PCR), in situ hybridization (ISH), or Immunohistochemistry (IHC). The function of TP73-AS1 in proliferation, apoptosis, migration, and invasion of medulloblastoma cells was evaluated using cell counting Kit-8 (CCK-8), flow cytometry, and transwell assay, respectively. The protein levels were determined by Western blot. Bioinformatics analysis and dual-luciferase reporter assay, RNA immunoprecipitation (RIP) and pull-down assay were used to search and confirm the target gene of TP73-AS1 and miR-494-3p. The effect of TP73-AS1 knockdown in vivo was detected by animal experiment.

Results

The levels of TP73-AS1 and EIF5A2 were up-regulated, while miR-494-3p expression was down-regulated in medulloblastoma tissues and cells, ELF5A2 was a direct target of miR-494-3p, and miR-494-3p bound to TP73-AS1. The knockdown of TP73-AS1 inhibited cell proliferation, invasion, migration, and promoted apoptosis of medulloblastoma cells, while the miR-494-3p inhibitor abolished the effects of TP73-AS1 knockdown on medulloblastoma cells.

Conclusion

TP73-AS1 positively regulated EIF5A2 expression by sponging miR-494-3p. These findings suggested that TP73-AS1 served as an oncogene and promoted the progression of medulloblastoma.

LncRNA BANCR promotes tumorigenesis and enhances adriamycin resistance in colorectal cancer

Colorectal cancer (CRC) is the third most common malignancy in the United States. Chemotherapeutic resistance is a massive obstacle for cancer treatment. The roles and molecular basis of long non-coding RNA BRAF-activated noncoding RNA (BANCR) in CRC progression and adriamycin (ADR) resistance have not been extensively identified. In this study, we found that BANCR and CSE1L expressions were upregulated in CRC tumor tissues. Meanwhile, CSE1L expression was correlated with depth of CRC. BANCR silencing suppressed cell proliferation and invasion capacity, increased apoptotic rate and potentiated cell sensitivity to ADR. CSE1L downregulation triggered a reduction of cell proliferation and invasion ability, and an increase of apoptosis rate and cell sensitivity to ADR. CSE1L overexpression attenuated si-BANCR-mediated anti-proliferation, anti-invasion and pro-apoptosis effects in CRC cells. BANCR acted as a molecular sponge of miR-203 to sequester miR-203 away from CSE1L in CRC cells, resulting in the upregulation of CSE1L expression. CSE1L knockdown inhibited expressions of DNA-repair-related proteins (53BP1 and FEN1) in HCT116 cells. BANCR knockdown also inhibited tumor growth and enhanced ADR sensitivity in CRC mice model. In conclusion, BANCR knockdown suppressed CRC progression and strengthened chemosensitization of CRC cells to ADR possibly by regulating miR-203/CSE1L axis, indicating that BANCR might be a promising target for CRC treatment.

MicroRNA-203 diminishes the stemness of human colon cancer cells by suppressing GATA6 expression

The interaction between hyaluronan and CD44, an important cancer stem-cell marker, stimulates various tumor cell-specific functions such as the stemness of tumor cells. microRNA-203 (miR-203) can be downregulated by this interaction in human colorectal cancer (CRC) cells, which increases their stemness; however, the underlying mechanism is not yet defined. Here, we show that overexpression and sequestration of miR-203 in HCT-116 and HT-29 human CRC cells reduces and enhances their stemness, respectively. We also show that GATA-binding factor 6 (GATA6) is a direct target of miR-203. Our results indicate that upregulated expression of this transcription factor not only restores the self-renewal abilities of miR-203-overexpressing HCT-116 and HT-29 cells but also promotes the stemness properties of their parental counterparts. More important, we show that silencing the expression of either LRH-1 or Hes-1 is sufficient to diminish the stemness-promoting effects of GATA6 in human CRC cells. Together, our findings delineate the stemness-inhibitory mechanism of miR-203 in human CRC cells and suggest that this miR is a potential therapeutic agent for colorectal cancer.

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

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

Identification and expression of microRNAs in european eels Anguilla anguilla from two natural sites with different pollution levels

MicroRNAs (miRNAs) are a class of small non-coding RNA that control multiple biological processes through negative post-transcriptional regulation of gene expression. Recently a role of miRNAs in the response of aquatic organisms to environmental toxicants emerged. Toxicant-induced changes in miRNA expression might then represent novel biomarkers to evaluate the health status of these organisms. In this study, we aimed to identify the miRNA repertoire in the liver of the European eel Anguilla anguilla and to compare their differential expression between a polluted site located in the Gironde Estuary and a pristine site in Arcachon Bay (France). A total of 299 mature miRNAs were identified. In polluted water, 19 miRNAs were up-regulated and 22 were down-regulated. We predicted that these differentially expressed miRNAs could target 490 genes that were involved in ribosome biogenesis, response to hormones, response to chemical and chromatin modification. Moreover, we observed only few examples (29) of negative correlation between the expression levels of miRNAs and their targets suggesting that, in the system studied, miRNAs might not only regulate gene expression directly by degrading mRNA but also by inhibiting protein translation or by regulating other epigenetic processes. This study is the first example of in situ investigation of the role of miRNAs in the response of a fish species to water quality. Our findings provide new insights into the involvement of epigenetic mechanisms in the response of animals chronically exposed to pollution and pave the way for the utilization of miRNAs in aquatic ecotoxicology.

Eukaryotic initiation factor 5A2 and human digestive system neoplasms

Eukaryotic initiation factor 5A2 (eIF5A2), as one of the two isoforms in the family, is reported to be a novel oncogenic protein that is involved in multiple aspects of many types of human cancer. Overexpression or gene amplification of EIF5A2 has been demonstrated in many cancers. Accumulated evidence shows that eIF5A2 initiates tumor formation, enhances cancer cell growth, increases cancer cell metastasis, and promotes treatment resistance through multiple means, including inducing epithelial–mesenchymal transition, cytoskeletal rearrangement, angiogenesis, and metabolic reprogramming. Expression of eIF5A2 in cancer correlates with poor survival, advanced disease stage, as well as metastasis, suggesting that eIF5A2 function is crucial for tumor development and maintenance but not for normal tissue homeostasis. All these studies suggest that eIF5A2 is a useful biomarker in the prediction of cancer prognosis and serves as an anticancer molecular target. This review focuses on the expression, subcellular localization, post-translational modifications, and regulatory networks of eIF5A2, as well as its biochemical functions and evolving clinical applications in cancer, especially in human digestive system neoplasms.

Sevoflurane inhibits the migration and invasion of colorectal cancer cells through regulating ERK/MMP-9 pathway by up-regulating miR-203

Surgery resection is the primary treatment for colorectal cancer (CRC) patients with the risk of cancer dissemination and metastasis. Sevoflurane is one inhalational anesthesia which regulates migration and invasion in varying cancers. However, the effect of sevoflurane on CRC cells and its mechanism remain poorly understood. In this study, SW620 and HCT116 cells were treated with different concentrations of sevoflurane for 6 h in vitro. We measured the effect of sevoflurane on cell survival, migration and invasion by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide or trans-well assays. Moreover, we explored the interaction between sevoflurane and miR-203 and Roundabout1 (Robo1) as well as the extracellular signal-regulated kinase (ERK) and matrix metalloproteinase-9 (MMP-9) pathway. Results showed that sevoflurane inhibited cell migration and invasion in SW620 and HCT116 cells in a concentration dependent manner. Moreover, different concentrations of sevoflurane suppressed the phosphorylation of ERK. miR-203 expression was impaired while sevoflurane reversed the expression of miR-203 in CRC cells. In addition, inhibition of miR-203 attenuated the inhibitory effect of sevoflurane on cell migration, invasion and phosphorylated ERK level. Notably, MMP-9, as a downstream of ERK, was involved in sevoflurane-mediated processes in CRC cells. Besides, Robo1 was indicated as a target of miR-203 and inhibited by sevoflurane treatment. These results indicated that sevoflurane suppressed cell migration and invasion through regulating ERK/MMP-9 pathway via miR-203/Robo1 in CRC cells, indicating important clinical implications for anesthetic agents to prevent metastasis in CRC.

MicroRNA-203 reinforces stemness properties in melanoma and augments tumorigenesis in vivo

One of the challenges encountered in microRNA (miRNA) studies is to observe their dual role in different conditions and cells. This leads to a tougher prediction of their behavior as gene expression regulators. miR-203 has been identified to play a negative role in the progression of malignant melanoma; however, it has been reported, with dual effect, as both an oncomiR and tumor suppressor miRNA in some malignancies, such as breast cancer, meanwhile, the role of miR-203 in melanoma stem cells or even metastatic cells is unclear. In the present study, after observation of upregulation of miR-203 in melanoma patient's serum and also melanospheres as cancer stem cells model, we examined its overexpression on the stemness potential and migration ability of melanoma cells. Our data demonstrated that the increased miR-203 level was significantly associated with significant increase in the ability of proliferation, colony and spheres formation, migration, and tumorigenesis in A375 and NA8 cells. All of these changes were associated with enhancement of BRAF, several epithelial to mesenchymal transition factors, and stemness genes. In conclusion, our results clearly determined that miR-203 could be down-regulateddownregulated in melanoma tissues but be overexpressed in melanoma stem cells. It has an important role as oncomiR and promote repopulation, tumorigenicity, self-renewal, and migration. Therefore, we suggested overexpression of miR-203 as biomarker for early detection of metastasis. However, more studies are needed to validate our data.

Extracellular small non-coding RNA contaminants in fetal bovine serum and serum-free media

In the research field of extracellular vesicles (EVs), the use of fetal bovine serum (FBS) depleted of EVs for in vitro studies is advocated to eliminate the confounding effects of media derived EVs. EV-depleted FBS may either be prepared by ultracentrifugation or purchased commercially. Nevertheless, these preparations do not guarantee an RNA-free FBS for in vitro use. In this study we address the RNA contamination issue, of small non-coding (nc)RNA in vesicular or non-vesicular fractions of FBS, ultracentrifugation EV-depleted FBS, commercial EV-depleted FBS, and in our recently developed filtration based EV-depleted FBS. Commercially available serum- and xeno-free defined media were also screened for small ncRNA contamination. Our small ncRNA sequencing data showed that all EV-depleted media and commercially available defined media contained small ncRNA contaminants. Out of the different FBS preparations studied, our ultrafiltration-based method for EV depletion performed the best in depleting miRNAs. Certain miRNAs such miR-122 and miR-203a proved difficult to remove completely and were found in all media. Compared to miRNAs, other small ncRNA (snRNA, Y RNA, snoRNA, and piRNA) were difficult to eliminate from all the studied media. Additionally, our tested defined media contained miRNAs and other small ncRNAs, albeit at a much lower level than in serum preparations. Our study showed that no media is free of small ncRNA contaminants. Therefore, in order to screen for baseline RNA contamination in culturing media, RNA sequencing data should be carefully controlled by adding a media sample as a control. This should be a mandatory step before performing cell culture experiments in order to eliminate the confounding effects of media.

BCAT1 and miR-2504: novel methylome signature distinguishes spindle/desmoplastic melanoma from superficial malignant peripheral nerve sheath tumor

Superficial/cutaneous malignant peripheral nerve sheath tumor is a rare soft tissue neoplasm that shares morphological, immunohistochemical, and molecular features with spindle/desmoplastic melanoma. We aimed to identify a methylome signature to distinguish these two entities. We analyzed 15 cases of spindle/desmoplastic melanoma and 15 cases of cutaneous malignant peripheral nerve sheath tumor in 23 men and 7 women. DNA from formalin-fixed, paraffin-embedded tissues was extracted and processed using the Illumina Infinium Methylation EPIC array interrogating 866,562 CpG sites. Using a home-grown informatics pipeline, we identified differentially methylated positions between the two entities. Functional network analysis for enrichment signatures was performed using DAVID tools. Identified differentially methylated positions were compared with the Cancer Genome Atlas's cutaneous melanoma dataset and a recently published malignant peripheral nerve sheath tumor dataset to assess the specificity of the identified signature. Unsupervised hierarchical clustering showed different patterns of methylation in cutaneous malignant peripheral nerve sheath tumor and spindle/desmoplastic melanoma. Two probes, cg20783223 and cg13332552, colocalized in the promoter region of BCAT1 and miR-2504. Pathway analysis highlighted enrichment in a subset of genes involved in breast and gastric cancer centered on BCAT1 and downstream activated genes in the mTOR pathway. Our study identifies BCAT1 as a novel methylome signature distinguishing spindle/desmoplastic melanoma from cutaneous malignant peripheral nerve sheath tumor.

COUP‑TFII promotes epithelial‑mesenchymal transition by inhibiting miR‑34a expression in colorectal cancer

Chicken ovalbumin upstream promoter‑transcription factor II (COUP‑TFII) expression is upregulated in colorectal cancer and is associated with its progression and a poor prognosis. The aim of the present study was to determine whether COUP‑TFII regulates colorectal cancer cell (CRC) invasion and migration by inhibiting microRNA (miR)‑34a. Transwell system and wound healing assays were performed to examine cell invasiveness and migration, respectively. Reverse transcription polymerase chain reaction and western blotting were used to detect the RNA and protein levels of target molecules, respectively. The results revealed that COUP‑TFII knockdown significantly inhibited CRC invasion and migration. In addition, the expression of miR‑34a, a well‑known tumor suppressor was revealed to be inversely correlated with COUP‑TFII expression. The miR‑34a mimic significantly reduced CRC invasion and migration abilities, while the miR‑34a inhibitor enhanced CRC invasion and migration activity. There was no significant difference between the negative small interfering RNA and miR‑34a inhibitor groups following knockdown of COUP‑TFII. Furthermore, western blotting demonstrated that miR‑34a mimics inhibited the epithelial‑mesenchymal transition (EMT) process of CRCs, while the miR‑34a inhibitor had the opposite effect. Taken together, the results demonstrate that miR‑34a regulates CRC invasion and migration by examining the mechanism by which COUP‑TFII regulates EMT.

Distinct shed microvesicle and exosome microRNA signatures reveal diagnostic markers for colorectal cancer

Extracellular vesicle (EV) microRNAs are of major interest as potential diagnostic biomarkers in all cancer types. This study aims to identify miRNA profiles of shed microvesicles (sMVs) and exosomes (Exos) secreted from the isogenic colorectal cancer (CRC) cell lines SW480 and SW620 and evaluate their ability to predict CRC. Deep sequencing of miRNAs in parental cell lysates (CLs) and highly-purified sMVs and Exos was performed. We focused on miRNAs enriched in EVs and dysregulated miRNAs in metastatic cells (SW620) relative to primary cancer cells (SW480). We investigated the ability of EV miRNA signatures to predict CRC tumours using 594 tumours (representing different pathological stages) and 11 normal samples obtained from TCGA. In SW480 and SW620 cells we identified 345 miRNAs, of which 61 and 73 were upregulated and downregulated in SW620-CLs compared to SW480-CLs, respectively. Selective distribution of cellular miRNAs into EVs results in distinct miRNA signatures for sMVs and Exos in each cell line. Cross cell line comparisons of EV miRNA profiles reveal a subset of miRNAs critical in CRC progression from primary carcinoma to metastasis. Many miRNAs non-detectable (<5 TPM) in CLs were significantly enriched (>1000 TPM) in secreted EVs. Strikingly, miR-7641 which is non-detectable in SW480-CL but upregulated in SW620-CL is highly enriched in EVs secreted from both cell lines. Pearson correlation analysis demonstrated that EV miRNA profiles can be used to predict CRC tumours with ~96% accuracy. Our findings suggest that EV miRNA profiles from CRC cell lines may allow prediction of CRC tumours, and that miR-7641 may serve as an attractive candidate for the specific, non-invasive diagnosis and prognosis of CRC.

The predictive powers of plasma trefoil factor 3 or its related micro RNAs for patients with hepatocellular carcinoma

Background

Earlier diagnosis is beneficial for the prognosis of hepatocellular carcinoma (HCC). Alpha fetoprotein (AFP) is the most widely used biomarker for HCC, but its sensitivity and specificity are only 60 and 90%, respectively. Therefore, it is of great clinical significance to identify early prognostic biomarkers for HCC, especially a blood-based biomarker as it offers several advantages over tissue-based biomarkers. Trefoil factor 3 (TFF3), a novel secretory protein, was over-expressed in HCC tissues, indicating it might be a blood-based biomarker for HCC. In addition, circulating microRNAs have been investigated as biomarkers for HCC, indicating that miR-7-5p and miR-203a-3p, which are reported or predicted to target TFF3, also hold promise as blood-based biomarkers for HCC.

Methods

We enrolled 43 patients who were firstly diagnosed HCC and matched 47 control subjects without HCC. The levels of TFF3, miR-7-5p and miR-203a-3p were tested in the plasma of HCC patients. Moreover, we assayed the correlation of TFF3 with its related micro RNAs, miR-7-5p and miR-203a-3p, and evaluated their predictive powers for HCC.

Results

Decrease of TFF3 was associated with increase of miR-203a-3p in the plasma of HCC patients and they displayed potent predictive powers for HCC diagnosis. However, there was no significant change of plasma miR-7-5p between HCC and control group.

Conclusion

Decrease of TFF3 correlated with increase of miR-203a-3p in the plasma of HCC patients and they could be additional biomarkers to improve sensitivity and specificity in the diagnosis of HCC.

MicroRNA-588 regulates invasion, migration and epithelial-mesenchymal transition via targeting EIF5A2 pathway in gastric cancer

Background

miRNAs are potential regulators of genes in many cancers. Here, we confirmed that the expression of miR-588 decreased in gastric cancer (GC) tissues and cells.

Materials and methods

Sixty-seven GC tissues along with noncancerous tissues adjacent to them were included in the study. Quantitative real-time reverse transcription-PCR study was done to quantify the expression levels of mature miRNA. The expression of proteins was determined by Western blot and transwell chamber assay for invasion and migration studies. Immunohistochemical analysis and luciferase assay were done for evaluating the expression of epithelial–mesenchymal transition (EMT) markers and activity of EIF5A2, respectively. In vivo metastatic assay was done by injecting MGC-803 cells into nude mice.

Results

In the 5-year predicted survival study of GC patients included in the study, we found that miR-588 acted as a specific prognostic marker. Overexpression of miR-588 resulted in suppression of cell invasion, migration and progression of EMT, whereas suppression of miR-588 inverted the effects in both in vivo and in vitro experiments. miR-588 retained EIF5A2 by directly binding to the 3′-UTR. EIF5A2 was overexpressed in GC tissue samples, and the expression of miR-588 was inversely correlated to the levels of EIF5A2. The impact of miR-588 on invasion, migration and progression of EMT may be partially due to miR-588–mediated alterations of EiF5A2.

Conclusion

Overall, the findings of the study suggest that miR-588 acts as a tumor suppressor by regulating the invasion, migration and EMT via EIF5A2 pathway, hence presenting miR-588 as a prognostic marker as well as a therapeutic target for GC.

Non-target Genes Regulate miRNAs-Mediated Migration Steering of Colorectal Carcinoma

MicroRNAs (miRNAs) trigger a two-layer regulatory network directly or through transcription factors and their co-regulators. Unlike miR-375, the role of miR-145 and miR-224 in inhibiting or driving cancer cell migration is controversial. This study is a step towards addressing the potential of miR-375, miR-145 and miR-224 expression modulation to inhibit colorectal carcinoma (CRC) cells migration in vitro through regulation of non-target genes VEGFA, TGFβ1, IGF1, CD105 and CD44. Transwell migration assay results revealed a significant subdue of migration ability of cells transfected with miR-375 and miR-145 mimics and miR-224 inhibitor. Real time PCR data showed that expression of VEGFA, TGFβ1, IGF1, CD105 and CD44 was downregulated as a consequence of exogenous re-expression of miR-375 and inhibition of miR-224. On the other hand, ectopic expression of miR-145 did not affect VEGFA, TGFβ1 and CD44 expression, while it elevated CD105 and suppressed IGF1 expression. MAP4K4, a predicted target of miR-145, was validated as a target that could play a role in miR-145-mediated regulation of migration. At mRNA level, no change was observed in expression of MAP4K4 in cells with restored expression of miR-145, while western blotting analysis revealed a 25% reduction of protein level. By applying luciferase reporter assay, a significant decrease in luciferase activity was observed, supporting that miR-145 directly target 3' UTR of MAP4K4. The study highlighted the involvement of non-target genes VEGFA, TGFβ1, IGF1, CD105 and CD44 in mediating anti- and pro-migratory effect of miR-375 and miR-224, respectively, and validated MAP4K4 as a direct target of anti-migratory miR-145.