MiR-203 down-regulates Rap1A and suppresses cell proliferation, adhesion and invasion in prostate cancer

CircTHSD4 promotes the malignancy and docetaxel (DTX) resistance in prostate cancer by regulating miR-203/HMGA2 axis

Objective

Circular ribose nucleic acids (circRNAs) are implicated in tumor progression and drug resistance of prostate cancer (PCa). The current work explored the function of circ_0005203 (circTHSD4) in the malignancy and docetaxel (DTX) resistance of PCa.

Methods

circTHSD4 expression within PCa as well as matched non-carcinoma samples was measured through real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, a subcellular fraction assay was conducted to determine circTHSD4 subcellular localization within PCa cells. In addition, we performed a Western blot (WB) assay to detect high-mobility-group A2 protein (HMGA2) levels. Besides, functional associations of two molecules were investigated through dual luciferase reporter assay. Cell Counting Kit (CCK)-8, colony formation together with Transwell assay was conducted to assess malignant phenotypes of PCa cells, whereas flow cytometry was performed to determine cell apoptosis. Furthermore, a xenograft mouse model was constructed to verify the effect of circTHSD4 on the carcinogenesis of PCa cells.

Results

According to RT-qPCR results, circTHSD4 was up-regulated within PCa tissues and cells, which predicted the dismal prognostic outcome of PCa cases. circTHSD4 silencing within PCa cells markedly suppressed cell growth, migration, and colony formation. circTHSD4 silencing remarkably elevated PCa cell apoptosis and carcinogenesis within the xenograft model. Further, circTHSD4 silencing enhanced docetaxel (DTX) sensitivity in PCa cells. Furthermore, we demonstrated that circTHSD4 modulated the malignancy of PCa cells by regulating HMGA2 expression through sponging miR-203.

Conclusion

Together, our findings suggest that circTHSD4 overexpression could promote the malignant phenotype and DTX resistance in PCa through the regulation of the miR-203/HMGA2 axis.

miR-129-2-3p inhibits colon cancer cell proliferation by down-regulating the expression of BZW1

BACKGROUND AND STUDY AIMS

MicroRNA (miRNA) is involved in diverse biological and physiological processes of tumors. Dysregulation of miRNA will induce a series of human diseases. miR-129-2-3p has vital effects in the pathogenesis of various tumors. However, the regulatory function of miR-129-2-3p in colon cancer remains to be clarified. This study investigated the role of miR-129-2-3p targeting BZW1 in proliferation, apoptosis, migration, and invasion of colon cancer.

PATIENTS AND METHODS

Here, RT-qPCR was applied to measure the miR-129-2-3p levels in colon cancer tissues. The predicted targets of miR-129-2-3p were identified by bioinformatics and verified using luciferase reporter assay. The effects of miR-129-2-3p on colon cancer were detected by CCK-8, colony formation, transwell chamber test, wound healing, and flow cytometry assays. Finally, the influence of miR-129-2-3p on tumor growth was studied. Nude mice were xenografted with transfected Lovo cells by subcutaneous injection of 5 × 105 cells in 100 µl. HE staining and TUNEL were used to assess metastasis ability.

RESULTS

miR-129-2-3p level in colon cancer tissue was significantly reduced. Furthermore, it was verified that BZW1 was a target of miR-129-2-3p, and its expression in colon cancer cells was inhibited by miR-129-2-3p. Additionally, miR-129-2-3p inhibited colon cancer cell proliferation, colony formation, mobility ability and tumor growth, and promoted cell apoptosis by targeting BZW1. miR-129-2-3p overexpression in tumor xenografts in vivo decreased BZW1 expression, and suppressed tumor growth.

CONCLUSION

Collectively, these findings indicated that miR-129-2-3p exerts a suppressive role in colon cancer cells by directly targeting BZW1, and may have significant therapeutic implications for patients with colon cancer.

MiRNA-30a-5p/VCAN Arrests Tumor Metastasis via Modulating the Adhesion of Lung Adenocarcinoma Cells

Previous research indicated that the dysregulation of miRNA-30a-5p has a correlation with cell metastasis of lung adenocarcinoma (LUAD). But the study about the molecular regulatory mechanism of miRNA-30a-5p in LUAD cell metastasis is limited. Thus, we discussed the mechanism of miRNA-30a-5p and its biological function in LUAD cells. By utilizing bioinformatics analysis, how miRNA-30a-5p was expressed in LUAD tissue was determined and its downstream target genes were predicted. The signaling pathways where these target genes enriched were analyzed. Several in vitro experiments were applied for cell function detection: dual-luciferase assay for validating the targeting relationship between miRNA-30a-5p and its target gene; quantitative real-time polymerase chain reaction for testing the expression of miRNA-30a-5p and its target gene in LUAD cells; MTT, transwell, cell adhesion, flow cytometry and immunofluorescence assays for examining the capabilities of LUAD cells to proliferate, migrate, invade, adhere, apoptosis and epithelial-mesenchymal transition (EMT) effect; Western blot for determining the expression of adhesion-related proteins and EMT-related proteins. Down-regulated miRNA-30a-5p was discovered in LUAD cells, but on the contrary, VCAN was upregulated. MiRNA-30a-5p overexpression notably repressed the virulent progression of LUAD cells. Besides, dual-luciferase assay validated the targeting relationship between miRNA-30a-5p and VCAN. MiRNA-30a-5p, by negatively regulating VCAN, was capable of hindering LUAD cell proliferation, migration, invasion, adhesion, viability and EMT. It was illustrated that miRNA-30a-5p could downregulate VCAN to retard the malignant progression of LUAD cells, which provides novel insights into LUAD pathogenesis, suggesting that miRNA-30a-5p/VCAN axis can be a promising anti-cancer target for LUAD.

The Role of microRNAs in Gene Expression and Signaling Response of Tumor Cells to an Acidic Environment

Many tumors are characterized by marked extracellular acidosis due to increased glycolytic metabolism, which affects gene expression and thereby tumor biological behavior. At the same time, acidosis leads to altered expression of several microRNAs (Mir7, Mir183, Mir203, Mir215). The aim of this study was to analyze whether the acidosis-induced changes in cytokines and tumor-related genes are mediated via pH-sensitive microRNAs. Therefore, the expression of Il6, Nos2, Ccl2, Spp1, Tnf, Acat2, Aox1, Crem, Gls2, Per3, Pink1, Txnip, and Ypel3 was examined in acidosis upon simultaneous transfection with microRNA mimics or antagomirs in two tumor lines in vitro and in vivo. In addition, it was investigated whether microRNA expression in acidosis is affected via known pH-sensitive signaling pathways (MAPK, PKC, PI3K), via ROS, or via altered intracellular Ca2+ concentration. pH-dependent microRNAs were shown to play only a minor role in modulating gene expression. Individual genes (e.g., Ccl2, Txnip, Ypel3) appear to be affected by Mir183, Mir203, or Mir215 in acidosis, but these effects are cell line-specific. When examining whether acid-dependent signaling affects microRNA expression, it was found that Mir203 was modulated by MAPK and ROS, Mir7 was affected by PKC, and Mir215 was dependent on the intracellular Ca2+ concentration. Mir183 could be increased by ROS scavenging. These correlations could possibly result in new therapeutic approaches for acidotic tumors.

MicroRNAs Regulate Tumorigenesis by Downregulating SOCS3 Expression: An In silico Approach

Tumor microenvironment is characterized by the occurrence of significant changes due to disrupted signaling pathways that affect a broad spectrum of cellular activities such as proliferation, differentiation, signaling, invasiveness, migration, and apoptosis. Similarly, a downregulated suppressor of cytokine signaling 3 (SOCS3) promotes increased JAK/STAT function due to aberrant cytokine signaling, which results in increased cell proliferation, differentiation, and migration. Multiple carcinomas including breast cancer, prostate cancer, hepatocellular carcinoma, pancreatic cancer, and colorectal cancer involve the disruption of SOCS3 expression due to microRNA overexpression. MicroRNAs are small, conserved, and non-coding RNA molecules that regulate gene expression through post-transcriptional inhibition and mRNA destabilization. The aim of this study was to identify putative microRNAs that interact with SOCS3 and downregulate its expression. In this study, miRWalk, TargetScan, and miRDB were used to identify microRNAs that interact with SOCS3, whereas RNA22 was utilized to identify the binding sites of 238 significant microRNAs. The tertiary structures of shortlisted microRNAs and SOCS3 regions were predicted through MC Sym and RNAComposer, respectively. For molecular docking, HDOCK was used, which predicted 80 microRNA-messengerRNA complexes and the interactions of the top 5 shortlisted complexes were assessed. The complexes were shortlisted on the basis of least binding affinity score and maximum confidence score. This study identifies the interactions of known (miR-203a-5p) and novel (miR-6756-5p, miR-6732-5p, miR-1203, miR-6887-5p) microRNAs with SOCS3 regions due to their maximum interactions. Identifying the interactions of these microRNAs with SOCS3 will significantly advance the understanding of oncomiRs (miRNAs that are associated with cancer development) in tumor development due to their influence on SOCS3 expression. These insights will assist in future studies to understand the significance of miRNA-SOCS3-associated tumor development and progression.

Rap1A accelerates homocysteine-induced ANA-1 cells inflammation via synergy of FoxO1 and DNMT3a

Abnormal elevation of homocysteine (Hcy) level accelerates atherosclerosis through promote macrophage inflammation, while the precise mechanisms remain to be well elucidated. Previous study revealed that Rap1A is involved in the development of atherosclerosis, but little is known regarding the regulation of macrophage inflammation induced by Hcy and its potential mechanisms. In the present study, we demonstrated that Hcy upregulates Rap1A expression and knockdown of Rap1A inhibited pro-inflammatory cytokines IL-6 and TNF-α levels in ANA-1 cells. Mechanistically, DNMT3a-mediated DNA hypomethylation of Rap1A promoter accelerates Hcy-induced ANA-1 cells inflammation. Furthermore, FoxO1 transcriptionally activate Rap1A by direct binding to its promoter. More importantly, Hcy could enhance FoxO1 interaction with DNMT3a and synergistically promote the expression of Rap1A resulting in accelerate ANA-1 cells inflammation. These data indicate that Rap1A is a novel and important regulator in Hcy-induced ANA-1 cells inflammation.

An overview of prostate cancer (PCa) diagnosis: Potential role of miRNAs

Prostate cancer is the second most frequently diagnosed cancer among men worldwide, with the estimated sixth leading cause of cancer death. Despite major advancements in clinical biology and imaging, digital rectal examination (DRE), prostate-specific antigen (PSA), and biopsies indication remain the keystone for screening. Several kits are used to detect genomic changes and non-coding RNAs in the sample. However, its indication remains controversial for screening purposes. There is an urged need for non-invasive biomarkers to implement precision medicine. Recent research shows that miRNAs have an important role in the diagnostic, prognostic, and therapeutic agents as non-invasive biomarkers. Though prostate cancer data remains controversial in other cancer types, such as breast cancer, miR-21 expression is upregulated. Here, we reported a prolonged revision of miRNAs as prostate cancer prognostic, diagnostic, and predictive tools, including data on androgen receptor (AR) signaling, epithelial-mesenchymal transition (EMT) process, and cancer stem cells (CSCs) regulation. The combined utilization of miRNAs with other tests will help patients and clinicians to select the most appropriate personalized treatment and to avoid overdiagnosis and unnecessary biopsies. Future clinical applications of our reported novel miRNAs have a substantial role in the primary diagnosis of prostate cancer to help treatment decisions.

Role of acidosis-sensitive microRNAs in gene expression and functional parameters of tumors in vitro and in vivo

Background: The acidic extracellular environment of tumors has been shown to affect the malignant progression of tumor cells by modulating proliferation, cell death or metastatic potential. The aim of the study was to analyze whether acidosis-dependent miRNAs play a role in the signaling cascade from low pH through changes in gene expression to functional properties of tumors in vitro and in vivo.

Methods: In two experimental tumor lines the expression of 13 genes was tested under acidic conditions in combination with overexpression or downregulation of 4 pH-sensitive miRNAs (miR-7, 183, 203, 215). Additionally, the impact on proliferation, cell cycle distribution, apoptosis, necrosis, migration and cell adhesion were measured.

Results: Most of the genes showed a pH-dependent expression, but only a few of them were additionally regulated by miRNAs in vitro (Brip1, Clspn, Rif1) or in vivo (Fstl, Tlr5, Txnip). Especially miR-215 overexpression was able to counteract the acidosis effect in some genes. The impact on proliferation was cell line-dependent and most pronounced with overexpression of miR-183 and miR-203, whereas apoptosis and necrosis were pH-dependent but not influenced by miRNAs. The tumor growth was markedly regulated by miR-183 and miR-7. In addition, acidosis had a strong effect on cell adhesion, which could be modulated by miR-7, miR-203 and miR-215.

Conclusions: The results indicate that the acidosis effect on gene expression and functional properties of tumor cells could be mediated by pH-dependent miRNAs. Many effects were cell line dependent and therefore do not reflect universal intracellular signaling cascades. However, the role of miRNAs in the adaptation to an acidic environment may open new therapeutic strategies.

MAPK-RAP1A Signaling Enriched in Hepatocellular Carcinoma Is Associated With Favorable Tumor-Infiltrating Immune Cells and Clinical Prognosis

Background

MAPK-RAP1A signaling, which is involved in cancer progression, remains to be defined. Upregulation of MAPK-RAP1A signaling accounts for most cancers that harbor high incident rate, such as non-small cell lung cancer (NSCLC) and pancreatic cancer, especially in hepatocellular carcinoma (HCC). MAPK-RAP1A signaling plays an important function as clinical diagnosis and prognostic value in cancers, and the role of MAPK-RAP1A signaling related with immune infiltration for HCC should be elucidated.

Methods

Microarray data and patient cohort information from The Cancer Genome Atlas (TCGA; n = 425) and International Cancer Genome Consortium (ICGC; n = 405) were selected for validation. The Cox regression and least absolute shrinkage and selection operator (LASSO) were used to construct a clinical prognostic model in this analysis and validation study. We also tested the area under the curve (AUC) of the risk signature that could reflect the status of predictive power by determining model. MAPK-RAP1A signaling is also associated with tumor-infiltrating immune cells (TICs) as well as clinical parameters in HCC. The GSEA and CIBERSORT were used to calculate the proportion of TICs, which should be beneficial for the clinical characteristics (clinical stage, distant metastasis) and positively correlated with the survival of HCC patients.

Results

HCC patients with enrichment of MAPK-RAP1A signaling were associated with clinical characteristics and favorable T cell gamma delta (Vδ T cells), and STMN1, RAP1A, FLT3, HSPA8, ANGPT2, and PGF were used as candidate biomarkers for risk scores of HCC. To determine the molecular mechanism of this signature gene association, Gene Set Enrichment Analysis (GSEA) was proposed. Cytokine-cytokine receptor interaction, TGF-β signaling pathway, and Intestinal immune network for IgA production gene sets were closely related in MAPK-RAP1A gene sets. Thus, we established a novel prognostic prediction of HCC to deepen learning of MAPK-RAP1A signaling pathways.

Conclusion

Our findings demonstrated that HCC patients with enrichment of MAPK-RAP1A signaling were associated with clinical characteristics and favorable T cell gamma delta (Vδ T cells), which may be a novel prognostic prediction of HCC.

Rac1/Wave2/Arp3 Pathway Mediates Rat Blood-Brain Barrier Dysfunction under Simulated Microgravity Based on Proteomics Strategy

The blood-brain barrier (BBB) is critical to maintaining central nervous system (CNS) homeostasis. However, the effects of microgravity (MG) on the BBB remain unclear. This study aimed to investigate the influence of simulated MG (SMG) on the BBB and explore its potential mechanism using a proteomic approach. Rats were tail-suspended to simulate MG for 21 days. SMG could disrupt the BBB, including increased oxidative stress levels, proinflammatory cytokine levels, and permeability, damaged BBB ultrastructure, and downregulated tight junctions (TJs) and adherens junctions (AJs) protein expression in the rat brain. A total of 554 differentially expressed proteins (DEPs) induced by SMG were determined based on the label-free quantitative proteomic strategy. The bioinformatics analysis suggested that DEPs were mainly enriched in regulating the cell–cell junction and cell–extracellular matrix biological pathways. The inhibited Ras-related C3 botulinum toxin substrate 1 (Rac1)/Wiskott–Aldrich syndrome protein family verprolin-homologous protein 2 (Wave2)/actin-related protein 3 (Arp3) pathway and the decreased ratio of filamentous actin (F-actin) to globular actin contributed to BBB dysfunction induced by SMG. In the human brain microvascular endothelial cell (HBMECs), SMG increased the oxidative stress levels and proinflammatory cytokine levels, promoted apoptosis, and arrested the cell cycle phase. Expression of TJs and AJs proteins were downregulated and the distribution of F-actin was altered in SMG-treated HBMECs. The key role of the Rac1/Wave2/Arp3 pathway in BBB dysfunction was confirmed in HBMECs with a specific Rac1 agonist. This study demonstrated that SMG induced BBB dysfunction and revealed that Rac1/Wave2/Arp3 could be a potential signaling pathway responsible for BBB disruption under SMG. These results might shed a novel light on maintaining astronaut CNS homeostasis during space travel.

Involvement of miR-337 in high glucose-suppressed osteogenic differentiation in bone marrow mesenchymal stem cells via negative regulation of Rap1A

This study aims to investigate the inhibitory effect of microRNA-337 (miR-337) on osteogenic differentiation in bone marrow mesenchymal stem cells and its action of mechanisms. Overexpression and knockdown of miR-337 were performed in bone marrow mesenchymal stem cells (BMSCs). Cell proliferation was assessed by using a cell counting kit-8 (CCK-8), mineralization assay was performed by alizarin red staining, and alkaline phosphatase activity was then measured. Luciferase reporter assay was applied to verify miR-337 binding to Ras-related protein 1A (Rap1A) mRNA. Reverse transcription and quantitative polymerase chain reaction (RT-qPCR) was applied to measure the expressions of runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteocalcin (OCN), osteopontin (OPN), bone morphogenetic protein (BMP2), and miR-337. Then the protein level of Rap1A was determined by western blot analysis. High glucose inhibited osteogenic differentiation but increased the level of miR-337. Overexpression of miR-337 inhibited osteogenic differentiation in high glucose-treated BMSCs, while the knockdown of miR-337 reversed this process. Luciferase reporter assay confirmed that the presumed pairing binding site of miRNA-337 was in the 3'-UTR of the Rap1A WT. In addition, the knockdown of Rap1A distinctly repressed osteogenic differentiation, which blocked the effect of miR-337-knockdown on osteogenic differentiation in high glucose-treated BMSCs. MiR-337 could repress osteogenic differentiation in high glucose-treated BMSCs directly targeting Rap1A, thus provide a potential therapeutic strategy for patients with diabetic osteoporosis in clinic.

miR-203 inhibits cell proliferation and ERK pathway in prostate cancer by targeting IRS-1

INTRODUCTION

Prostate cancer (PCa) is one of the most common types of cancer in men. In the course of the development and progression of this disease, abnormal expression of miR-203 is usually accompanied. However, its role in prostate tumorigenesis and the underlying mechanism are poorly understood.

METHODS

Dual luciferase reporter gene analysis was used to detect miR-203 binding site in insulin receptor substrates 1 (IRS-1). Cell proliferation was assessed by MTT assay in PCa cells with either IRS-1 knockdown or miR-203 overexpression. IRS-1 and other proteins expression in PCa cells was assessed by Western Blot.

RESULTS

we found that the insulin receptor substrates 1 (IRS-1) is a novel target of miR-203 in PCa and miR-203 can specifically bind to the 3'UTR region of the IRS-1 thus suppresses its expression. Moreover, we demonstrate that miR-203 functions as a tumor suppressor by directly targeting IRS-1 to inhibit cell proliferation and migration which results in PCa cell cycle arrest. Importantly, miR-203 overexpression blocks ERK signalling pathway by down-regulating IRS-1 expression.

CONCLUSIONS

Our results show a novel link between miR-203 and IRS-1, and reveal the importance of strict control of IRS - 1 by miR-203 in the progression of PCa, suggesting miR-203 may act as a promising target for the diagnosis and treatment of advanced PCa.

Long non-coding RNA LINC01116 accelerates the progression of keloid formation by regulating miR-203/SMAD5 axis

BACKGROUND

Emerging evidence reveals the importance of long non-coding RNAs (lncRNAs) in the development and progression of keloid formation. However, the roles and molecular mechanism of lncRNA LINC01116 in the progression of keloid formation remain largely unknown.

METHODS

The expression levels of LINC01116, microRNA-203 (miR-203) and SMAD family member 5 (SMAD5) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell proliferation, migration and invasion were detected by Cell counting Kit-8 (CCK-8) assay and transwell assay. Flow cytometry and western blot assay were used to examine cell apoptosis and extracellular matrix (ECM) production. The interaction between miR-203 and LINC01116 or SMAD5 was predicted by bioinformatics analysis and verified by dual-luciferase reporter and RNA Immunoprecipitation (RIP) and RNA pull-down assays.

RESULTS

LINC01116 and SMAD5 were upregulated while miR-203 was downregulated in keloid tissues and keloid fibroblasts. LINC01116 knockdown suppressed the proliferation, migration, invasion, and ECM production but induced apoptosis in keloid fibroblasts through enhancing miR-203 and inhibiting SMAD5. Moreover, SMAD5 was identified as a direct target of miR-203 and miR-203 could directly bind to LINC01116. Besides, LINC01116 regulated SMAD5 expression by targeting miR-203.

CONCLUSION

Downregulation of LINC01116 inhibited the progression of keloid formation by regulating miR-203/SMAD5 axis, which might provide a novel target for keloid therapy.

Serum extracellular vesicle miR-203a-3p content is associated with skeletal muscle mass and protein turnover during disuse atrophy and regrowth

Small noncoding microRNAs (miRNAs) are important regulators of skeletal muscle size, and circulating miRNAs within extracellular vesicles (EVs) may contribute to atrophy and its associated systemic effects. The purpose of this study was to understand how muscle atrophy and regrowth alter in vivo serum EV miRNA content. We also associated changes in serum EV miRNA with protein synthesis, protein degradation, and miRNA within muscle, kidney, and liver. We subjected adult (10 mo) F344/BN rats to three conditions: weight bearing (WB), hindlimb suspension (HS) for 7 days to induce muscle atrophy, and HS for 7 days followed by 7 days of reloading (HSR). Microarray analysis of EV miRNA content showed that the overall changes in serum EV miRNA were predicted to target major anabolic, catabolic, and mechanosensitive pathways. MiR-203a-3p was the only miRNA demonstrating substantial differences in HS EVs compared with WB. There was a limited association of EV miRNA content to the corresponding miRNA content within the muscle, kidney, or liver. Stepwise linear regression demonstrated that EV miR-203a-3p was correlated with muscle mass and muscle protein synthesis and degradation across all conditions. Finally, EV miR-203a-3p expression was significantly decreased in human subjects who underwent unilateral lower limb suspension (ULLS) to induce muscle atrophy. Altogether, we show that serum EV miR-203a-3p expression is related to skeletal muscle protein turnover and atrophy. We suggest that serum EV miR-203a-3p content may be a useful biomarker and future work should investigate whether serum EV miR-203a-3p content is mechanistically linked to protein synthesis and degradation.

Implication of the p53-Related miR-34c, -125b, and -203 in the Osteoblastic Differentiation and the Malignant Transformation of Bone Sarcomas

The formation of the skeleton occurs throughout the lives of vertebrates and is achieved through the balanced activities of two kinds of specialized bone cells: the bone-forming osteoblasts and the bone-resorbing osteoclasts. Impairment in the remodeling processes dramatically hampers the proper healing of fractures and can also result in malignant bone diseases such as osteosarcoma. MicroRNAs (miRNAs) are a class of small non-coding single-strand RNAs implicated in the control of various cellular activities such as proliferation, differentiation, and apoptosis. Their post-transcriptional regulatory role confers on them inhibitory functions toward specific target mRNAs. As miRNAs are involved in the differentiation program of precursor cells, it is now well established that this class of molecules also influences bone formation by affecting osteoblastic differentiation and the fate of osteoblasts. In response to various cell signals, the tumor-suppressor protein p53 activates a huge range of genes, whose miRNAs promote genomic-integrity maintenance, cell-cycle arrest, cell senescence, and apoptosis. Here, we review the role of three p53-related miRNAs, miR-34c, -125b, and -203, in the bone-remodeling context and, in particular, in osteoblastic differentiation. The second aim of this study is to deal with the potential implication of these miRNAs in osteosarcoma development and progression.

Donor polymorphisms of Rap1A rs494453 contribute to a higher risk of hepatocellular carcinoma recurrence following liver transplantation

Background: Hepatocellular carcinoma (HCC) recurrence appears commonly after liver transplantation (LT), and it severely affected the long-term survival of patients. Previous studies have proved that Rap1A is involved in hepatocarcinogenesis and metastasis, and demonstrated the significant association between Rap1A gene rs494453 polymorphism and HCC. However, the relationship between Rap1A rs494453 polymorphism and HCC recurrence after LT remained unclear.

Methods: A total of 74 HCC patients who underwent LT from July 2005 to June 2015 was analyzed. The genotypes of both donors and recipients had been confirmed as Rap1A rs494453. The independent risk factors that associated with HCC recurrence were investigated with univariate and multivariate logistic regression analysis. The recurrence-free (RFS) and overall survival (OS) were calculated with Cox regression analysis. The Rap1A rs494453 genotype frequencies were determined using the Χ² test and the minor allele frequencies (MAFs) of Rap1A rs494453 genotypes were calculated by Hardy-Weinberg equilibrium.

Results: We found that the donor Rap1A rs494453 polymorphism was profoundly associated with HCC recurrence after LT. Moreover, the Milan criteria, microvascular invasion and donor Rap1A rs494453 genotype were proved to be independent risk factors for HCC recurrence. Patients with donor AG/GG genotypes had a distinct lower RFS and OS than AA genotype. The TNM stage, Milan criteria, microvascular invasion, and donor Rap1A rs494453 genotype were independent factors for the RFS of LT patients.

Conclusions: Donor Rap1A rs494453 is a potential predictive marker for HCC recurrence risk after LT.

MicroRNA-101-5p Suppresses the Expression of the Ras-Related Protein RAP1A

MicroRNAs (miRs) are small, non-coding RNAs that negatively regulate gene expression. The stem-loop sequence miR-101-1 generates mature miR-101-5p and miR-101-3p. The function and target mRNA of miR-101-5p have not yet been elucidated in detail. Here, we demonstrate that miR-101-5p inhibits the expression of RAP1A, a member of the RAS gene family. Transfection of a miR-101-5p mimic significantly inhibited the expression of RAP1A mRNA in HeLa, HEK293, A549, and COLO201 cells. The same treatment significantly inhibited cell proliferation. The cytostatic effect with transfection of miR-101-5p was antagonized by treatment with the RAP inhibitor salirasib. These results suggested that miR-101-5p inhibits RAP1A, and thus, the expression levels of miR-101-5p regulate cell proliferation.

LncRNA PCAT-1 upregulates RAP1A through modulating miR-324-5p and promotes survival in lung cancer

INTRODUCTION

Lung cancer is the malignant tumor with the fastest increase in morbidity and mortality and the greatest threat to human health and life. Long non-coding RNA (lncRNA) is emerging as an important regulator in many cancers. Recently, it was found that lncRNA prostate cancer associated transcript 1 (PCAT-1) was up-regulated in lung cancer, playing oncogenic roles. However, the underlying regulatory mechanism of PCAT-1 remains unknown.

MATERIAL AND METHODS

The expression levels of PCAT-1 and miR-324-5p were analyzed by real-time PCR, and RAP1A expression was determined by western blotting. RNA pull-down, luciferase and western blotting assays were used to examine the target relationship between PCAT-1 and miR-324-5p or that between miR-324-5p and RAP1A. The functional effects of PCAT-1 and miR-324-5p were examined using cell viability and cell apoptosis assays.

RESULTS

PCAT-1 overexpression remarkably promoted cell proliferation and suppressed cell apoptosis. Mechanistic investigations demonstrated that PCAT-1 can interact with miR-324-5p and repress its expression, thereby increasing the expression of its target RAP1A. Additionally, rescue experiments revealed that PCAT-1 served as an oncogene partly through sponging miR-324-5p and upregulating RAP1A in lung cancer cells.

CONCLUSIONS

Our findings demonstrate that on account of the dual function of pro-proliferation and anti-apoptosis, PCAT-1/miR-324-5p/RAP1A may be novel candidates for application in the diagnosis, prognosis and therapy of lung cancer.

CADM1 inhibits ovarian cancer cell proliferation and migration by potentially regulating the PI3K/Akt/mTOR pathway

Previous studies have shown that cell adhesion molecule 1 (CADM1), an immunoglobulin superfamily member, is frequently inactivated but functions as a tumor suppressor in many solid tumors. However, the characterization of CADM1 expression in ovarian cancer cells and the mechanisms of its tumor suppressor function are not fully understood. We generated ovarian cancer cell lines in which CADM1 was stably upregulated or downregulated. CADM1 expression was significantly decreased in ovarian cancer tissue and cells lines. Functionally, knockdown of CADM1 promoted the growth, migration and invasion of ovarian cancer cells. Conversely, further experimental evidence indicated that overexpression of CADM1 inhibited the migration and invasion of ovarian cancer cells potentially through inhibition of the PI3K/Akt/mTOR signaling pathway by regulating upstream regulators (LXR/RXR, IGF1, IFI44L and C4BPA) and downstream effectors (APP, EDN1, TGFBI and Rap1A). In conclusion, CADM1 inhibits ovarian cancer cell proliferation and migration by potentially regulating the PI3K/Akt/mTOR signaling pathway. CADM1 could be a potential therapeutic target for ovarian cancer.

Decreased expression of miR-410-3p correlates with poor prognosis and tumorigenesis in human glioma

Background

Gliomas are the most common type of primary tumors in the central nervous system. This study aimed to investigate the biological role of miR-410-3p in glioma and elucidate the potential molecular mechanisms involved.

Methods

The expression levels of miR-410-3p in clinical tissue samples and glioma cell lines were determined using qRT-PCR analysis. The clinical significance of miR-410-3p in glioma was evaluated using Kaplan-Meier survival analysis and Fisher’s exact test. The effects of miR-410-3p on glioma cell proliferation, apoptosis, migration and invasion were investigated using MTT assays, flow cytometry, transwell migration and invasion assays. Besides, corresponding mechanistic studies were carried out.

Results

miR-410-3p was significantly down-regulated in glioma tissues. Besides, Kaplan-Meier analysis demonstrated that patients with low miR-410-3p expression had a shorter overall survival. Decreased miR-410-3p expression was associated with larger tumor size, lower Karnofsky performance score (KPS), and higher World Health Organization (WHO) grade. Over-expression of miR-410-3p suppressed cell proliferation, migration, and invasion, and accelerated apoptosis; whereas depletion of miR-410-3p facilitated cell proliferation, migration, and invasion, and inhibited apoptosis. Mechanistic investigations demonstrated that Ras-related protein 1A (RAP1A) was a direct target of miR-410-3p, and that rescue of RAP1A expression reversed miR-410-3p over-expression-induced inhibitory effects on cell proliferation, migration, and invasion. Notably, miR-410-3p over-expression repressed tumor growth in mouse xenograft models.

Conclusion

Our findings indicate that miR-410-3p functions as a tumor suppressor in glioma by directly targeting RAP1A. Thus, this study may provide some new insights into gliomagenesis and progression.

MiR-501-3p functions as a tumor suppressor in non-small cell lung cancer by downregulating RAP1A

MicroRNA-501-3p (miR-501-3p) has been reported to play tumor-suppressive roles in different cancers; however, its expression pattern and biological function in non-small cell lung cancer (NSCLC) remain unknown. In this study, we noted downregulation of miR-501-3p in NSCLC tissues and cell lines. Functional assays showed that overexpression of miR-501-3p suppressed NSCLC cell proliferation, clonogenicity, migration, and invasion. Moreover, miR-501-3p overexpression attenuated in vivo tumor growth in a nude mouse model. In terms of the mechanism, RAP1A was identified as a novel target of miR-501-3p. Overexpression of RAP1A strongly attenuated the inhibitory effects of miR-501-3p on the capacity of NSCLC cells for proliferation and motility. In the clinical samples of NSCLC, miR-501-3p levels negatively correlated with RAP1A expression, which was upregulated in NSCLC. Collectively, these results indicate that miR-501-3p acts as a tumor suppressor in NSCLC by directly targeting RAP1A mRNA and may serve as a theranostic biomarker for patients with NSCLC.

Rap1A promotes esophageal squamous cell carcinoma metastasis through the AKT signaling pathway

Ras‑associated protein 1A (Rap1A) is a member of the Ras subfamily of small GTP‑binding proteins and is found to promote metastasis in several types of cancer. However, the functional role and molecular mechanism of action in Rap1A in esophageal squamous cell carcinoma (ESCC) is not fully understood. In the present study, Rap1A was found to be upregulated in ESCC tissues and its expression was correlated with cancer stage. Functional studies revealed that Rap1A could promote ESCC metastasis by stimulating cell migration and invasion in vivo and in vitro. Further study indicated that the transcriptional factor SP1 increased Rap1A expression via promoter binding and transcription activation. Furthermore, Rap1A promoted epithelial‑to‑mesenchymal transition, possibly through the AKT signaling pathway. Hence, the findings of the present study indicated that Rap1A may be a potential prognostic marker or therapeutic target for ESCC.

Combination of Gentiana rhodantha and Gerbera anandria in the BL02 formula as therapeutics to non-small cell lung carcinoma acting via Rap1/cdc42 signaling: A transcriptomics/ bio-informatics biological validation approach

BACKGROUND

Non-small cell lung cancer (NSCLC) ranks the most commonly diagnosed and highest mortality-leading cancer worldwide despite a variety of treatment strategies are available. The highly heterogeneous and aggressive property of NSCLC as well as its poor prognosis indicates the need for novel therapeutic targets identification. The objective of this study is to identify potential targets from the adjuvant herbal formula BL02 using a combined approach of high throughput transcriptomics and network pharmacology.

METHODS

The quality and stability of BL02 were assessed by UHPLC analysis. The inhibitory effect of BL02 on NSCLC was measured by in vivo orthotopic intrathoracic mouse model and in vitro cellular models. EGFR-mutant HCC827 and wild type A549 cell lines were employed. Transcriptomics analysis was introduced to profile the gene expression of NSCLC cells treated with BL02; Network pharmacology and molecular docking analyses predicted the interaction of compounds and NSCLC targets. Immuno-blotting and pull-down assays verified the putative targets.

RESULTS

The UHPLC analysis revealed that BL02 was relatively stable between batches of production and for 24 months of storage. Orally administration of BL02 was safe and effective to inhibit pulmonary NSCLC growth in mice implanted with A549 and HCC827-generated tumors. BL02 exhibited relatively low cytotoxicity to NSCLC cells in vitro, but potently suppressed NSCLC cell motility. The transcriptomic analysis illustrated that EGFR and cellular adhesion-related signaling is involved in BL02 action. Further bioinformatics analysis validated BL02 activity is mediated by cdc42-regulated signaling. BL02 depolymerized the actin cytoskeleton through suppressing cdc42 and deactivating its upstream molecule Rap1. These effects may be primarily mediated by the direct binding of 5-methylcoumarin-4-cellobioside and mangiferin from BL02 to Rap1 protein.

CONCLUSION

Our study proposes an integration model of experimental, transcriptomic and bioinformatics analyses in the identification of novel therapeutic target of NSCLC from an adjuvant herbal formula BL02. Our findings revealed that inhibition of Rap1/cdc42 signaling by active compounds 5-methylcoumarin-4-cellobioside and mangiferin from BL02 might be potentially effective therapy for NSCLC.

Eukaryotic initiation factor 3, subunit C silencing inhibits cell proliferation and promotes apoptosis in human ovarian cancer cells

Ovarian cancer remains the leading cause of death among all gynaecological cancers, illustrating the urgent need to understand the molecular mechanisms involved in this disease. Eukaryotic initiation factor 3c (EIF3c) plays an important role in protein translation and cancer cell growth and proliferation, but its role in human ovarian cancer is unclear. Our results showed that EIF3c silencing significantly up-regulated 217 and down-regulated 340 genes. Ingenuity Pathway Analysis (IPA) indicated that the top differentially expressed genes are involved in ‘Classical Pathways’, ‘Diseases and Functions’ and ‘Networks’, especially those involved in signalling and cellular growth and proliferation. In addition, eIF3c silencing inhibited cellular proliferation, enhanced apoptosis and regulated the expression of apoptosis-associated proteins. In conclusion, these results indicate that by dysregulating translational initiation, eIF3c plays an important role in the proliferation and survival of human ovarian cancer cells. These results should provide experimental directions for further in-depth studies on important human ovarian cancer cell pathways.

MicroRNA-203 Acts as a Potent Suppressor in Septic Shock by Alleviating Lung Injury via Inhibition of VNN1

BACKGROUND

Septic shock, the most serious complication of sepsis, is a life-threatening disease that is mainly characterized by hypoperfusion and multiple organ failure. Various aberrantly expressed microRNAs (miRNAs) have been reported to be related to septic shock. We explored the regulatory effect of microRNA-203 (miR-203) on lung injury in septic shock mice.

METHODS

Microarray-based gene expression profiling related to septic shock identified the differentially expressed gene vanin-1 (VNN1) and potential regulatory miR-203. miR-203 was predicted to mediate VNN1 expression, thus affecting septic shock, which was investigated by treatment with miR-203 mimic, miR-203 inhibitor, and siRNA-VNN1 in septic shock mouse models. Polymorphonuclear neutrophils (PMNs) and pulmonary alveolar macrophages in bronchoalveolar lavage fluid (BALF) as well as the wet/dry ratio of the lung were also measured to assess lung injury. Additionally, the effects of miR-203 on inflammatory cytokines, oxidative stress indexes, blood biochemical indexes, serine-threonine protein kinase (AKT) signaling pathway-related factors, and apoptosis-related factors were determined.

RESULTS

VNN1 was verified to be targeted and negatively regulated by miR-203. In mouse models of septic shock, weak expression of miR-203, high expression of VNN1, and inhibition of AKT signaling pathway were identified. In response to miR-203 mimic and VNN1 gene silencing, mouse models of septic shock displayed reduced apoptosis, MDA, ALT, and AST in lung tissues, decreased levels of TNF-α, IL-1β, IFN-γ, IL-10, and IL-6, in serum, and reduced PMN and PAM levels in BALF, in addition to elevated SOD activity. Notably, the presence of miR-203 mimic led to AKT signaling pathway activation.

CONCLUSION

This study shows that upregulating miR-203 can alleviate lung injury through activation of the AKT signaling pathway by downregulating VNN1 in septic shock.

The role of miRNAs as biomarkers in prostate cancer

There is an urged need of non-invasive biomarkers for the implementation of precision medicine. These biomarkers are required to these days for improving prostate cancer (PCa) screening, treatment or stratification in current clinical strategies. There are several commercial kits (Oncotype DX genomic prostate score^®, Prolaris^®, among others) that use genomic changes, rearrangement or even non-coding RNA events. However, none of them are currently used in the routine clinical practice. Many recent studies indicate that miRNAs are relevant molecules (small single-stranded non-coding RNAs that regulate gene expression of more than 30% of human genes) to be implement non-invasive biomarkers. However, contrasting to others tumors, such as breast cancer where miR-21 seems to be consistently upregulated; PCa data are controversial. Here we reported an extended revision about the role of miRNAs in PCa including data of AR signaling, cell cycle, EMT process, CSCs regulation and even the role of miRNAs as PCa diagnostic, prognostic and predictive tool. It is known that current biomedical research uses big-data analysis like Next Generation Sequencing (NGS) analysis. We also conducted an extensive online search, including the main platforms and kits for miRNAs massive analysis (like MiSeq, Nextseq 550, or Ion S5™ systems) indicating their pros, cons and including pre-analytical and analytical issues of miRNA studies.

Diagnostic and prognostic significance of serum miR-203 in patients with acute myeloid leukemia

MicroRNAs play important roles in the initiation and progression of acute myeloid leukemia (AML). This study aimed to detect serum miR-203 expression levels in AML and explore its potential clinical significance. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was performed to measure the serum miR-203 levels in 134 patients with AML and 70 healthy controls. The results demonstrated that serum miR-203 expression was significantly reduced in AML patients compared with healthy controls. Receiver operating characteristic curve (ROC) analysis revealed miR-203 could distinguish AML cases from normal controls. Low serum miR-203 levels were associated with worse clinical features, as well as poorer overall survival and relapse free survival of AML patients. Moreover, multivariate analysis confirmed low serum miR-203 expression to be an independent unfavorable prognostic predictor for AML. The bioinformatics analysis showed that the downstream genes and pathways of miR-203 was closely associated with tumorigenesis. Downregulation of miR-203 in AML cell lines upregulated the expression levels of oncogenic promoters such as CREB1, SRC and HDAC1. Thus, these findings demonstrated that serum miR-203 might be a promising biomarker for the diagnosis and prognosis of AML.

MicroRNA-203 impacts on the growth, aggressiveness and prognosis of hepatocellular carcinoma by targeting MAT2A and MAT2B genes

Hepatocellular carcinoma (HCC) is characterized by the down-regulation of the liver-specific methyladenosyltransferase 1A (MAT1A) gene, encoding the S-adenosylmethionine synthesizing isozymes MATI/III, and the up-regulation of the widely expressed methyladenosyltransferase 2A (MAT2A), encoding MATII isozyme, and methyladenosyltransferase 2B (MAT2B), encoding a β-subunit without catalytic action that regulates MATII enzymatic activity. Different observations showed hepatocarcinogenesis inhibition by miR-203. We found that miR-203 expression in HCCs is inversely correlated with HCC proliferation and aggressiveness markers, and with MAT2A and MAT2B levels. MiR-203 transfection in HepG2 and Huh7 liver cancer cells targeted the 3'-UTR of MAT2A and MAT2B, inhibiting MAT2A and MAT2B mRNA levels and MATα2 and MATβ2 protein expression. These molecular events were paralleled by an increase in SAM content and were associated with growth restraint and apoptosis, inhibition of cell migration and invasiveness, and suppression of the expression of CD133 and LIN28B stemness markers. In contrast, MAT2B transfection in the same cell lines led to a rise of both MATβ2 and MATα2 expression, associated with increases in cell growth, migration, invasion and overexpression of stemness markers and p-AKT. Altogether, our results indicate that the miR-203 oncosuppressor activity may at least partially depend on its inhibition of MAT2A and MAT2B and show, for the first time, an oncogenic activity of MAT2B linked to AKT activation.

miR-142-5p regulates pancreatic cancer cell proliferation and apoptosis by regulation of RAP1A

Pancreatic cancer, one of the fatal and aggressive malignancies, leads the sixth cancer-associated death in China. microRNAs are believed to exert function in the diagnosis and treatment of pancreatic cancer. In the present study, we firstly found that miR-142-5p was downregulated in pancreatic cancer tumor tissues while Ras-related protein Rap-1 A (RAP1A) was upregulated compared with para-carcinoma non-tumor tissues. Then, we found that RAP1A could be a putative target gene of miR-142-5p by bioinformatics tool TargetScan. Furthermore, we conducted luciferase reporter assay, RT-qPCR, western blot and correlation analysis to demonstrate that miR-142-5p could negatively regulate RAP1A expression by binding to its 3'UTR. In addition, cell-counting kit 8 (CCK-8) and flow cytometry assays certified that miR-142-5p overexpression may inhibit pancreatic cancer cell proliferation but promote cell apoptosis; while the variation could be reversed by co-transfected with pcDNA3.1-RAP1A. Finally, miR-142-5p overexpression downregulated p-ERK1/2, phosphate p38 mitogen-activated protein kinases (p-p38); however, the variation induced by miR-142-5p mimic could be reversed by co-transfected with pcDNA3.1-RAP1A. In conclusion, our findings indicate that targeting miR-142-5p may provide a novel strategy for the treatment of pancreatic cancer.

The Functional Role of Prostate Cancer Metastasis-related Micro-RNAs

The mortality of patients with hormone-resistant prostate cancer can be ascribed to a large degree to metastasis to distant organs, predominantly to the bones. In this review, we discuss the contribution of micro-RNAs (miRs) to the metastatic process of prostate cancer. The criteria for selection of miRs for this review were the availability of preclinical in vivo metastasis-related data in conjunction with prognostic clinical data. Depending on their function in the metastatic process, the corresponding miRs are up- or down-regulated in prostate cancer tissues when compared to matching normal tissues. Up-regulated miRs preferentially target suppressors of cytokine signaling or tumor suppressor-related genes and metastasis-inhibitory transcription factors. Down-regulated miRs promote epithelial-mesenchymal transition or mesenchymal-epithelial transition and diverse pro-metastatic signaling pathways. Some of the discussed miRs exert their function by simultaneously targeting epigenetic pathways as well as cell-cycle-related, anti-apoptotic and signaling-promoting targets. Finally, we discuss potential therapeutic options for the treatment of prostate cancer-related metastases by substitution or inhibition of miRs.

Regulat-INGs in tumors and diseases: Focus on ncRNAs

ING family genes (Inhibitor of Growth) are tumor suppressor genes that play a vital role in cell homeostasis. It has been shown that their expression is lost or diminished in many cancers and other diseases. The main mechanisms by which they are regulated in oncogenesis have not yet been fully elucidated. The involvement of non-coding RNAs (ncRNAs) and in particular microRNAs (miRNAs) in post-transcriptional gene regulation is well established. miRNAs are short sequences (18-25 nucleotides) that can bind to the 3 'UTR sequence of the targeted messenger RNA (mRNA), leading to its degradation or translational repression. Interactions between the ING family and miRNAs have been described in some cancers but also in other diseases. The involvement of miRNAs in ING family regulation opens up new fields of investigation, particularly for targeted therapies. In this review, we will summarize the regulatory mechanisms at the RNA and protein level of the ING family and focus on the interactions with ncRNAs.

miR-181a and miR-203 inhibit migration and invasion of laryngeal carcinoma cells by interacting with ATF2

MicroRNAs (miRNAs) have been recognized to modulate the progression of tumorigenesis by serving as oncogenes or tumor suppressors. Despite the involvement of miR-181a and miR-203 in several cancers as has been substantiated, their roles in laryngeal carcinoma (LC) remain unclear. In this study, the abundances of miR-181a, miR-203 and activating transcription factor 2 (ATF2) mRNA in LC cell lines were detected by RT-qPCR. Western blot was performed to detect the protein levels of N-cadherin, E-cadherin and ATF2. Cell migration and invasion ability were assessed by Trans-well assay. The putative binding sites between miR-181a or miR-203 and ATF2 were predicted using Bioinformatics software and further validated by Dual-Luciferase reporter and RNA immunoprecipitation (RIP) assays. Results showed reduced abundances of miR-181a and miR-203 in LC cell lines. Introduction of miR-181a or miR-203 reduced cell migration and invasion, which was further confirmed by the reduction of N-cadherin and increase of E-cadherin in LC cells. ATF2 was identified to be a potential target of miR-181a and miR-203. Absence of ATF2 overturned the stimulatory effects of anti-miR-181a and anti-miR-203 on cell migration and invasion in LC cells. Our findings suggested that miR-181a and miR-203 attenuated cell migration and invasion ability by directly targeting ATF2 in LC, providing novel insight into the regulatory mechanisms of miR-181a and miR-203 in LC.

The Many Faces of Rap1 GTPase

This review addresses the issue of the numerous roles played by Rap1 GTPase (guanosine triphosphatase) in different cell types, in terms of both physiology and pathology. It is one among a myriad of small G proteins with endogenous GTP-hydrolyzing activity that is considerably stimulated by posttranslational modifications (geranylgeranylation) or guanine nucleotide exchange factors (GEFs), and inhibited by GTPase-activating proteins (GAPs). Rap1 is a ubiquitous protein that plays an essential role in the control of metabolic processes, such as signal transduction from plasma membrane receptors, cytoskeleton rearrangements necessary for cell division, intracellular and substratum adhesion, as well as cell motility, which is needed for extravasation or fusion. We present several examples of how Rap1 affects cells and organs, pointing to possible molecular manipulations that could have application in the therapy of several diseases.

High expression of Ras-related protein 1A promotes an aggressive phenotype in colorectal cancer via PTEN/FOXO3/CCND1 pathway

Background

Colorectal cancer (CRC) is a commonly diagnosed digestive malignancy worldwide. Ras-related protein 1A (RAP1A) is a member of the Ras superfamily of small GTPases and has been recently identified as a novel oncoprotein in several human malignancies. However, its specific role in CRC remains unclear.

Method

In this study, we firstly analyzed its expression and clinical significance in a retrospective cohort of 144 CRC patients. Then, cellular assays in vitro and in vivo were performed to clarify its biological role in CRC cells. Finally, microarray analysis was utilized to investigate the molecular mechanisms regulated by RAP1A in CRC progression.

Results

Firstly, RAP1A expression was abnormally higher in CRC tissues as compared with adjacent normal tissues, and significantly correlated tumor invasion. High RAP1A expression was an independent unfavourable prognostic factor for CRC patients. Combining RAP1A expression and preoperative CEA level contributed to a more accurate prognostic stratification in CRC patients. Secondly, knockdown of RAP1A dramatically inhibited the growth of CRC cells, while it was opposite for RAP1A overexpression. Finally, the microarray analysis revealed RAP1A promoted CRC growth partly through phosphatase and tensin homolog (PTEN)/forkhead box O3(FOXO3)/cyclin D1(CCND1) signaling pathway. FOXO3 overexpression could partly mimic the inhibitory effect of RAP1A knockdown in CRC growth. Moreover, FOXO3 overexpression inhibited CCND1 expression, but had no impact on RAP1A and PTEN expression.

Conclusion

RAP1A promotes CRC development partly through PTEN/FOXO3 /CCND1 signaling pathway. It has a great potential to be an effective clinical biomarker and therapeutic target for CRC patients.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0827-y) contains supplementary material, which is available to authorized users.

A directly negative interaction of miR-203 and ZEB2 modulates tumor stemness and chemotherapy resistance in nasopharyngeal carcinoma

miR-203 is a tumor suppressor that is disregulated in numerous malignancies including nasopharyngeal carcinoma (NPC). However, the role of miR-203 in suppressing tumor stemness, chemotherapy resistance as well as its molecular mechanisms are unclear. In this study, we observed that miR-203 suppressed cell migration, invasion, tumor stemness, and chemotherapy resistance to cisplatin (DDP) in vitro and in vivo. miR-203 exerted these effects by targeting ZEB2 and downstream epithelial-mesenchymal transition (EMT) and tumor stemness signals. Interestingly we observed that miR-203 expression was directly suppressed by ZEB2 via targeting its promoter, which significantly reduced cell migration, invasion, tumor stemness, and chemotherapy resistance in NPC cells. Finally, we found that miR-203 was negatively correlated with ZEB2 expression in NPC tissues and tumor spheres. Our data demonstrate a directly negative feedback loop between miR-203 and ZEB2 participating in tumor stemness and chemotherapy resistance, highlighting the therapeutic potential of targeting this signal for NPC chemotherapy.

The PCAT3/PCAT9-miR-203-SNAI2 axis functions as a key mediator for prostate tumor growth and progression

Long non-coding RNAs (lncRNAs) have been reported to be of great importance in the formation and progression of a wide range of human carcinomas including prostate cancer (PCa). Among them, PCAT3 and PCAT9 have been identified as two prostate tissue-specific lncRNAs and are up-regulated in PCa. However, their roles in the biological characteristics of PCa have not been fully elucidated. In the present study, our data revealed that knockdown of PCAT3 and PCAT9 suppressed cellular proliferation, invasion, migration, angiogenesis and stemness in androgen-dependent LNCaP and 22Rv1 cells. Strikingly, bioinformatics analysis predicted that both PCAT3 and PCAT9 transcripts had two conserved binding sties for miR-203. Meanwhile, dual luciferase report assays revealed that miR-203 could suppress the luciferase activities of reporter plasmids carrying the binding site of miR-203 on the mRNA of PCAT3 or PCAT9. Quantitative RT-PCR (qRT-PCR) and RNA fluorescence in situ hybridization (RNA-FISH) showed that miR-203 mimic reduced the expression of PCAT3 and PCAT9 both in LNCaP and 22Rv1 cells. We also noted that both PCAT3 and PCAT9 inhibited miR-203 expression and alleviated repression on the expression of SNAI2, a critical regulator of epithelial-mesenchymal transition directly targeted by miR-203. Functionally, silence of miR-203 or ectopic expression of SNAI2 attenuated the inhibitory effect of PCAT3 and PCAT9 knockdown on cell proliferation and migration in vitro, and xenograft growth in vivo. Taken together, our data suggested that the PCAT3/PCAT9-miR-203-SNAI2 axis may serve as a promising diagnostic and therapeutic target for PCa.

Examining plasma microRNA markers for colorectal cancer at different stages

Circulating microRNAs (miRNAs) have emerged as promising biomarkers; however, few miRNAs have been reproducible and can be used in clinical practice. In this study, we screened the levels of 754 miRNAs using TaqMan array in 50 individual plasma samples from 10 demographically matched healthy controls and 40 colorectal cancer (CRC) patients (10 each of stage I-IV) and identified 22 miRNAs associated with the presence of and stages of CRC. Then we performed the validation for 11 miRNAs in an independent cohort including 187 CRC cases and 47 healthy controls. Comprehensive analyses showed that plasma miR-96 distinguished stage I-IV CRC from healthy controls with an area under curve (AUC) of 0.740; miR-203 separated stage III-IV CRC patients from stage I-II with an AUC of 0.757; and miR-141 differentiated stage IV CRC from stage I-III patients with an AUC of 0.851. Survival analyses showed that plasma miR-96 and miR-200b were independent prognostic factors for overall survival. Thus, we propose four miRNAs (miR-96, miR-203, miR-141 and miR-200b) as clinically validated circulating biomarkers for CRC prognosis that warrant further evaluation for clinical utility.

Targeting protein geranylgeranylation slows tumor development in a murine model of prostate cancer metastasis

The isoprenoid biosynthetic pathway (IBP) plays a critical role in providing substrates and enzymes necessary for the post-translational modification and thus activation of a number of proteins involved in prostate cancer metastasis. Previous work by our lab found novel compound disodium [(6Z,11E,15E)-9-[bis(sodiooxy)phosphoryl]-17-hydroxy-2,6,12,16-tetramethyheptadeca-2,6,11,15-tetraen-9-yl]phosphonate (GGOHBP), which inhibits the IBP enzyme geranylgeranyl diphosphate synthase (GGDPS), reduced protein geranylgeranylation without altering protein farnesylation. This activity significantly reduced adrenal gland tumor burden in a murine model of human prostate cancer metastasis which relied on treatment of established disease. The present study determined the ability of GGDPS inhibition to slow the development of prostate cancer metastasis in a preventative murine model. Using tail vein injection of human derived PC-3 prostate cancer cells 4 d after initiating daily GGOHBP or vehicle treatments, we found GGOHBP significantly reduced whole body tumor burden, significantly slowed the development of tumors, and prolonged overall survival as compared to vehicle treated animals. The observed reduction in soft tissue tumor burden corresponded to a biochemical reduction in Rap1A geranylgeranylation, which for prostate cancer is important in its own merit and which serves as a surrogate marker for Rho family, i.e. Rac, protein modification. This effect was present in all treated mice pointing to strong target engagement, which was not observed in non-tumor burdened tissues or control mice. Our findings reiterate a role for protein geranylgeranylation in the development of prostate cancer metastasis in vivo.

Gene expression profile identifies potential biomarkers for human intervertebral disc degeneration

The present study aimed to reveal the potential genes associated with the pathogenesis of intervertebral disc degeneration (IDD) by analyzing microarray data using bioinformatics. Gene expression profiles of two regions of the intervertebral disc were compared between patients with IDD and controls. GSE70362 containing two groups of gene expression profiles, 16 nucleus pulposus (NP) samples from patients with IDD and 8 from controls, and 16 annulus fibrosus (AF) samples from patients with IDD and 8 from controls, was downloaded from the Gene Expression Omnibus database. A total of 93 and 114 differentially expressed genes (DEGs) were identified in NP and AF samples, respectively, using a limma software package for the R programming environment. Gene Ontology (GO) function enrichment analysis was performed to identify the associated biological functions of DEGs in IDD, which indicated that the DEGs may be involved in various processes, including cell adhesion, biological adhesion and extracellular matrix organization. Pathway enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) demonstrated that the identified DEGs were potentially involved in focal adhesion and the p53 signaling pathway. Further analysis revealed that there were 35 common DEGs observed between the two regions (NP and AF), which may be further regulated by 6 clusters of microRNAs (miRNAs) retrieved with WebGestalt. The genes in the DEG‑miRNA regulatory network were annotated using GO function and KEGG pathway enrichment analysis, among which extracellular matrix organization was the most significant disrupted biological process and focal adhesion was the most significant dysregulated pathway. In addition, the result of protein‑protein interaction network modules demonstrated the involvement of inflammatory cytokine interferon signaling in IDD. These findings may not only advance the understanding of the pathogenesis of IDD, but also identify novel potential biomarkers for this disease.

MiR-203a-3p suppresses cell proliferation and metastasis through inhibiting LASP1 in nasopharyngeal carcinoma

BACKGROUND

miR-203a-3p was reported as a tumor suppressor and disregulated in many malignancies including nasopharyngeal carcinoma (NPC). However, its function in tumor growth and metastasis in NPC has rarely been reported.

METHODS

The expression level of miR-203a-3p in human NPC tissues and cell lines was detected via real-time PCR (RT-PCR). Cell proliferation, migration and invasion were assessed in vitro by MTT, colony formation and transwell assay, respectively. The function of miR-203a-3p in vivo was detected through NPC xenograft tumor growth and lung metastatic mice model. Dual-luciferase reporter assay was used to identify the direct target of miR-203a-3p.

RESULTS

The expression of miR-203a-3p was decreased in NPC tissues and cell lines in comparison with normal nasopharyngeal tissues and cell line. Ectopic expression of miR-203a-3p inhibited while inhibiting miR-203a-3p expression increased NPC cell proliferation, migration and invasion in vitro. MR-203a-3p overexpression suppressed xenograft tumor growth and lung metastasis in vivo. LASP1 was identified as a direct target of miR-203a-3p, which was confirmed by real-time PCR and western blotting assay. Ectopic expression of LASP1 partially reversed miR-203a-3p-mediated inhibition on proliferation, migration and invasion in NPC cells.

CONCLUSION

Collectively, miR-203a-3p suppresses tumor growth and metastasis through targeting LASP1 in NPC. The newly identified miR-203a-3p/LASP1 pathway provides further insights into the initiation and progression of NPC, which may represent a novel therapeutic target for NPC.

Silencing of lncRNA CCDC26 Restrains the Growth and Migration of Glioma Cells In Vitro and In Vivo via Targeting miR-203

Gliomas are the most common primary brain tumors with high mortality. The treatment for gliomas is largely limited due to its uncomprehending pathological mechanism. Here we aimed to investigate the effect of long noncoding RNA (lncRNA) coiled-coil domain-containing 26 (CCDC26) in glioma progression. In our study, the expression of CCDC26 was found upregulated in glioma tissues and cell lines compared with normal tissues and cell lines. Further exploration detected decreased cell proliferation and increased cell apoptosis in U-251 and M059J cells transfected with CCDC26-siRNA. In addition, the silencing of CCDC26 strongly reduced the wound closing rate and the number of invasive cells compared with the scramble group. Simultaneously, the expression of miR-203 was found suppressed in glioma tissues and cells lines. Suppressed level of miR-203 was then elevated in U-251 and M059J cells transfected with CCDC26-siRNA. The result of the luciferase activity assay also showed that the luciferase activity was strongly strengthened by adding the miR-203 inhibitor into the CCDC26 WT group. Moreover, CDCC26-siRNA counteracted the effect of the miR-203 inhibitor in facilitating cell viability and mobility in U-251 cells. The in vivo experiment also revealed that CCDC26-siRNA inhibited glioma growth and metastasis. Taken together, our research indicated a CCDC26/miR-203 pathway in regulating the growth and metastasis of gliomas, providing new viewpoints and promising targets for glioma therapy.

Deciphering the function of non-coding RNAs in prostate cancer

The advent of next-generation sequencing methods is fuelling the discovery of multiple non-coding RNA transcripts with direct implication in cell biology and homeostasis. This new layer of biological regulation seems to be of particular importance in human pathogenesis, including cancer. The aberrant expression of ncRNAs is a feature of prostate cancer, as they promote tumor-suppressive or oncogenic activities, controlling multicellular events leading to carcinogenesis and tumor progression. From the small RNAs involved in the RNAi pathway to the long non-coding RNAs controlling chromatin remodeling, alternative splicing, and DNA repair, the non-coding transcriptome represents the significant majority of transcriptional output. As such, ncRNAs appear as exciting new diagnostic, prognostic, and therapeutic tools. However, additional work is required to characterize the RNA species, their functions, and their applicability to clinical practice in oncology. In this review, we summarize the most important features of ncRNA biology, emphasizing its relevance in prostate carcinogenesis and its potential for clinical applications.

Rap1A promotes ovarian cancer metastasis via activation of ERK/p38 and notch signaling

As one of the Ras-associated proteins, Rap1A has been linked to cancer initiation and development. However, the precise function of Rap1A in ovarian cancer is still not understood. Here, we show that Rap1A promotes ovarian cancer tumorigenesis and metastasis via stimulating cell proliferation, migration and invasion both in vivo and in vitro. Mechanistic study showed that Rap1A activates extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and Notch pathways, leading to the enhanced expression of several epithelial-mesenchymal transition (EMT) markers such as slug, zeb1, vimentin, fibronectin, and MMP9. However, the pretreatment of Rap1A-overexpressing cells with the Notch inhibitor DAPT or ERK inhibitor (U0126) inhibited the up-regulated expression of those molecules. These findings provide the first evidence linking Rap1A with ovarian cancer development through the ERK/p38 and Notch signaling pathways, indicating that Rap1A may be used as a novel diagnostic marker or a therapeutic target for ovarian cancer.

miR-203a is involved in HBx-induced inflammation by targeting Rap1a

Hepatitis B virus (HBV) causes acute and chronic hepatitis, and is one of the major causes of cirrhosis and hepatocellular carcinoma. Accumulating evidence suggests that inflammation is the key factor for liver cirrhosis and hepatocellular carcinoma. MicroRNAs play important roles in many biological processes. Here, we aim to explore the function of microRNAs in the HBX-induced inflammation. First, microarray experiment showed that HBV⁺ liver samples expressed higher level of miR-203a compared to HBV^- liver samples. To verify these alterations, HBx-coding plasmid was transfected into HepG2 cells to overexpress HBx protein. The real-time PCR results suggested that over-expression of HBx could induce up-regulation of miR-203a. To define how up-regulation of miR-203a can induce liver cells inflammation, we over-expressed miR-203a in HepG2 cells. Annexin V staining and BrdU staining suggested that overexpression of miR-203a significantly increased the cell apoptosis and proliferation, meanwhile, over-expression of miR-203a could lead to a decrease in G0/G1 phase cells and an increase in G2/M phase cells. Some cytokines production including IL-6 and IL-8 were significantly increased, but TGFβ and IFNγ were decreased in miR-203a over-expressed HepG2 cells. Luciferase reporter assay experiments, protein mass-spectrum assay and real-time PCR all together demonstrated that Rap1a was the target gene of miR-203a. Further experiments showed that these alterations were modulated through PI3K/ERK/p38/NFκB pathways. These data suggested that HBV-infection could up-regulate the expression of miR-203a, thus down regulated the expression of Rap1a and affected the PI3K/ERK/p38/NFκB pathways, finally induced the hepatitis inflammation.

MicroRNA-203 Inversely Correlates with Differentiation Grade, Targets c-MYC, and Functions as a Tumor Suppressor in cSCC

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer and a leading cause of cancer mortality among solid organ transplant recipients. MicroRNAs (miR) are short RNAs that regulate gene expression and cellular functions. Here, we show a negative correlation between miR-203 expression and the differentiation grade of cSCC. Functionally, miR-203 suppressed cell proliferation, cell motility, and the angiogenesis-inducing capacity of cSCC cells in vitro and reduced xenograft tumor volume and angiogenesis in vivo. Transcriptomic analysis of cSCC cells with ectopic overexpression of miR-203 showed dramatic changes in gene networks related to cell cycle and proliferation. Transcription factor enrichment analysis identified c-MYC as a hub of miR-203-induced transcriptomic changes in squamous cell carcinoma. We identified c-MYC as a direct target of miR-203. Overexpression of c-MYC in rescue experiments reversed miR-203-induced growth arrest in cSCC, which highlights the importance of c-MYC within the miR-203-regulated gene network. Together, miR-203 acts as a tumor suppressor in cSCC, and its low expression can be a marker for poorly differentiated tumors. Restoration of miR-203 expression may provide a therapeutic benefit, particularly in poorly differentiated cSCC.

Gax regulates human vascular smooth muscle cell phenotypic modulation and vascular remodeling

Abnormal phenotypic modulation of vascular smooth muscle cells (VSMCs) is a hallmark of cardiovascular diseases such as atherosclerosis, hypertension and restenosis after angioplasty. Transcription factors have emerged as critical regulators for VSMCs function, and recently we verified inhibiting transcription factor Gax was important for controlling VSMCs proliferation and migration. This study aimed to determine its role in phenotypic modulation of VSMCs. Western blot revealed that overexpression of Gax increased expression of VSMCs differentiation marker genes such as calponin and SM-MHC 11. Then, Gax overexpression potently suppressed proliferation and migration of VSMCs with or without platelet-derived growth factor-induced-BB (PDGF-BB) stimuli whereas Gax silencing inhibited these processes. Furthermore, cDNA array analysis indicated that Rap1A gene was the downstream target of Gax in human VSMCs. And overexpression of Gax significantly inhibited expression of Rap1A in VSMCs with or without PDGF-BB stimuli. Moreover, overexpression of Rap1A decreased expression of VSMCs differentiation marker genes and increased proliferation and migration of VSMCs with or without PDGF-BB stimuli. Finally, Gax overexpression significantly inhibited the neointimal formation in carotid artery injury of mouse models, specifically through maintaining VSMCs contractile phenotype by decreasing Rap1A expression. In conclusion, these results indicated that Gax was a regulator of human VSMCs phenotypic modulation by targeting Rap1A gene, which suggested that targeting Gax or its downstream targets in human VSMCs may provide an attractive approach for the prevention and treatment of cardiovascular diseases.

Overexpression of miR-203 sensitizes paclitaxel (Taxol)-resistant colorectal cancer cells through targeting the salt-inducible kinase 2 (SIK2)

MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression through the endogenous RNA interference machinery. Treatments with combination of chemotherapy with surgery are essential for advanced-stage colorectal cancer. However, the development of chemoresistance is a major obstacle for clinical application of anticancer drugs. In this study, we report a miR-203-SIK2 axis that involves in the regulation of Taxol sensitivity in colon cancer cells. MiR-203 is downregulated in human colon tumor specimens and cell lines compared with their normal counterparts. We report miR-203 is correlated with Taxol sensitivity: overexpression of miR-203 sensitizes colon cancer cells and the Taxol-resistant cells display downregulated miR-203 compared with Taxol-sensitive cells. We identify SIK2 as a direct target of miR-203 in colorectal cancer cells. Overexpression of miR-203 complementary pairs to the 3' untranslated region (UTR) of SIK2, leading to the sensitization of Taxol resistant cells. In addition, miR-203 and the salt-inducible kinase 2 (SIK2) are reverse expressed in human colorectal tumors. Finally, we demonstrate recovery of SIK2 by overexpression of SIK2-desensitized Taxol-resistant cells, supporting the miR-203-mediated sensitization to Taxol, is through the inhibition of SIK2. In general, our study will provide mechanisms of the microRNA-based anti-tumor therapy to develop anti-chemoresistance drugs.