miR‑873 inhibits colorectal cancer cell proliferation by targeting TRAF5 and TAB1

Explore on the Mechanism of miRNA-146a/TAB1 in the Regulation of Cellular Apoptosis and Inflammation in Ulcerative Colitis Based on NF-κB Pathway

OBJECTIVE

Ulcerative colitis (UC) is a chronic non-specific inflammatory disease of the rectum and colon with unknown etiology. A growing number of evidence suggest that the pathogenesis of UC is related to excessive apoptosis and production of inflammatory cytokines. However, the functions and molecular mechanisms associated with UC remain unclear.

MATERIALS AND METHODS

The in vivo and in vitro models of UC were established in this study. MiRNA or gene expression was measured by qRT-PCR assay. ELISA, CCK-8, TUNEL, and flow cytometry assays were applied for analyzing cellular functions. The interactions between miR-146a and TAB1 were verified by luciferase reporter and miRNA pull-down assays.

RESULTS

MiR-146a was obviously increased in UC patients, DSS-induced colitis mice, and TNF-α-induced YAMC cells, when compared to the corresponding controls. MiR- 146a knockdown inhibited the inflammatory response and apoptosis in DSS-induced colitis mice and TNF-α-induced YAMC cells. Mechanistically, we found that TAB1 was the target of miR-146a and miR-146a knockdown suppressed the activation of NF-κB pathway in UC. More importantly, TAB1 could overturn the inhibitory effect of antagomiR-146a on cell apoptosis and inflammation in UC.

CONCLUSION

MiR-146a knockdown inhibited cell apoptosis and inflammation via targeting TAB1 and suppressing NF-κB pathway, suggesting that miR-146a may be a new therapeutic target for UC treatment.

Predictive action of oncomiR in suppressing TP53 signaling pathway in hypoxia-conditioned colon cancer cell line HCT-116

Hypoxia-induced heterogeneity in colorectal cancer (CRC) significantly impacts patient survival by promoting chemoresistance. These conditions alter the regulation of miRNAs, key regulators of crucial processes like proliferation, apoptosis, and invasion, leading to tumor progression. Despite their promising potential as diagnostic and therapeutic targets, the underlying mechanisms by which miRNAs influence hypoxia-mediated tumorigenesis remain largely unexplored. This study aims to elucidate the action of miRNAs in HCT-116 colorectal cancer stem cells (CSCs) under hypoxia, providing valuable insights into their role in tumor adaptation and progression. MiRNA expression was determined using Nanostring nCounter, and bioinformatic analysis was performed to explain the molecular pathway. A total of 50 miRNAs were obtained with an average count of ≥ 20 reads for comparative expression analysis. The results showed that hypoxia-affected 36 oncomiRs were increased in HCT-116, and 14 suppressor-miRs were increased in MSCs. The increase in miRNA expression occurred consistently from normoxia to hypoxia and significantly differed between mesenchymal stem cells (MSCs) and HCT-116. Furthermore, miR-16-5p and miR-29a-3p were dominant in regulating the p53 signaling pathway, which is thought to be related to the escape mechanism against hypoxia and maintaining cell proliferation. More research with a genome-transcriptome axis approach is needed to fully understand miRNAs' role in adapting CRC cells and MSCs to hypoxia. Further research could focus on developing specific biomarkers for diagnosis. In addition, anti-miR can be developed as a therapy to prevent cancer proliferation or inhibit the adaptation of cancer cells to hypoxia.

IL-2RG as a possible immunotherapeutic target in CRC predicting poor prognosis and regulated by miR-7-5p and miR-26b-5p

Despite advances in treatment strategies, colorectal cancer (CRC) continues to cause significant morbidity and mortality, with mounting evidence a close link between immune system dysfunctions issued. Interleukin-2 receptor gamma (IL-2RG) plays a pivotal role as a common subunit receptor in the IL-2 family cytokines and activates the JAK-STAT pathway. This study delves into the role of Interleukin-2 receptor gamma (IL-2RG) within the tumor microenvironment and investigates potential microRNAs (miRNAs) that directly inhibit IL-2RG, aiming to discern their impact on CRC clinical outcomes. Bioinformatics analysis revealed a significant upregulation of IL-2RG mRNA in TCGA-COAD samples and showed strong correlations with the infiltration of various lymphocytes. Single-cell analysis corroborated these findings, highlighting IL-2RG expression in critical immune cell subsets. To explore miRNA involvement in IL-2RG dysregulation, mRNA was isolated from the tumor tissues and lymphocytes of 258 CRC patients and 30 healthy controls, and IL-2RG was cloned into the pcDNA3.1/CT-GFP-TOPO vector. Human embryonic kidney cell lines (HEK-293T) were transfected with this construct. Our research involved a comprehensive analysis of miRPathDB, miRWalk, and Targetscan databases to identify the miRNAs associated with the 3' UTR of human IL-2RG. The human microRNA (miRNA) molecules, hsa-miR-7-5p and hsa-miR-26b-5p, have been identified as potent suppressors of IL-2RG expression in CRC patients. Specifically, the downregulation of hsa-miR-7-5p and hsa-miR-26b-5p has been shown to result in the upregulation of IL-2RG mRNA expression in these patients. Prognostic evaluation of IL-2RG, hsa-miR-7-5p, and hsa-miR-26b-5p, using TCGA-COAD data and patient samples, established that higher IL-2RG expression and lower expression of both miRNAs were associated with poorer outcomes. Additionally, this study identified several long non-coding RNAs (LncRNAs), such as ZFAS1, SOX21-AS1, SNHG11, SNHG16, SNHG1, DLX6-AS1, GAS5, SNHG6, and MALAT1, which may act as competing endogenous RNA molecules for IL2RG by sequestering shared hsa-miR-7-5p and hsa-miR-26b-5p. In summary, this investigation underscores the potential utility of IL-2RG, hsa-miR-7-5p, and hsa-miR-26b-5p as serum and tissue biomarkers for predicting CRC patient prognosis while also offering promise as targets for immunotherapy in CRC management.

METTL14 mediates m6a modification on osteogenic proliferation and differentiation of bone marrow mesenchymal stem cells by regulating the processing of pri-miR-873

N6-methyl-adenosine (m6a) is involved in the occurrence and development of various diseases such as autogenic immune disease and tumors. Methyltransferases regulate primary (pri)-microRNA (miRNA/miR) processing by mediating m6a modifications, consequently affecting pathological processes including immune-related diseases by regulating both innate and adaptive immune cells. However, the roles of m6a on the biological functions of bone marrow mesenchymal stem cells (BMSCs) remain to be elucidated. The relative expression levels of methyltransferase-like 14 (METTL14) and other methyltransferases, demethylases, and miR-873 in bone samples from patients with osteoporosis and from normal individuals were measured by reverse transcription-quantitative PCR. Cell Counting Kit-8 assay was used to examine the proliferation of BMSCs. Co-immunoprecipitation (Co-IP) was used to investigate the binding of METTL14 to DiGeorge syndrome critical region 8 (DGCR8). RNA immunoprecipitation (RIP) was used to examine the binding of METTL14 to pri-miR-873. METTL14 and m6a modifications were highly detected in patients with osteoporosis compared with the controls. Co-IP results indicated that silencing of METTL14 reduced METTL14 and m6a modification levels in BMSCs. Downregulation of METTL14 significantly promoted the proliferation of BMSCs. RIP results suggested that METTL14/m6a methylation modification promoted the processing of pri-miR-873 by binding to DGCR8 in BMSCs. Furthermore, overexpression of miR-873 inhibited the proliferation of BMSCs. The results also showed that miR-873 mimics significantly inhibited the proliferation in small interfering (si)-METTL14 transfected BMSCs; however, miR-873 inhibitors markedly promoted the proliferation of si-METTL14 transfected BMSCs. METTL14 and m6a modifications were upregulated in osteoporosis samples. METTL14 promoted the processing of pri-miR-873 into mature miR-873 by regulating m6a modification. Furthermore, overexpression of miR-873 significantly inhibited the proliferation of BMSCs. Therefore, the METTL14/m6a/miR-873 axis may be a potential target for the treatment of osteoporosis.

Exosomal miR-767 from senescent endothelial-derived accelerating skin fibroblasts aging via inhibiting TAB1

Skin aging is a complicated physiological process, and microRNA-mediated regulation has been shown to contribute to this process. Exosomes mediate intercellular communication through miRNAs, mRNAs and proteins, and participate in many physiological and pathological processes. Vascular endothelial cell-derived exosomes have been confirmed to be involved in the development of many diseases, however, their effects on skin aging have not been reported. In this study, senescent endothelial cells could regulate skin fibroblast functions and promote cell senescence through exosomal pathway. miR-767 was highly expressed in senescent vascular endothelial cells and their exosomes, and miR-767 is also upregulated in skin fibroblasts after treatment with exosomes derived from senescent vascular endothelial cells. In addition, transfection with miR-767 mimic promoted senescence of skin fibroblasts, while transfection with miR-767 inhibitor reversed the effect of D-galactose. Double luciferase analysis confirmed that TAB1 was a direct target gene of miR-767. Furthermore, miR-767 expression was increased and TAB1 expression was decreased in D-galactose induced aging mice. In mice that overexpressed miR-767, HE staining showed thinning of dermis and senescence appearance. In conclusion, senescent vascular endothelial cell-derived exosome mediated miR-767 regulates skin fibroblasts through the exosome pathway. Our study reveals the role of vascular endothelial cell-derived exosomes in aging in the skin microenvironment and contributes to the discovery of new targets for delaying senescence.

Inducible MicroRNA-132 Inhibits the Production of Inflammatory Cytokines by Targeting TRAF6, TAK1, and TAB1 in Teleost Fish

The innate immune response is the first line of defense against pathogen infection. Eradication of pathogen infection requires appropriate immune and inflammatory responses, but excessive inflammation may cause inflammatory and autoimmune diseases. MicroRNAs (miRNAs) are a group of small noncoding RNAs, and accumulating evidence has shown that in mammals, they can act as negative regulators that participate in the regulation of inflammation and immune responses. However, the miRNA-mediated immune regulation networks in the inflammatory responses of lower vertebrates are largely unknown. In this study, we report an miRNA, miR-132, identified from miiuy croaker, that acts as a negative regulator in the host's bacterium-induced inflammatory response. We found that miR-132 expression was dramatically increased upon infection by the Gram-negative bacterium Vibrio harveyi and lipopolysaccharide (LPS). Inducible miR-132 inhibits the production of inflammatory cytokines by targeting tumor necrosis factor receptor-associated factor 6 (TRAF6), transforming growth factor-activated protein kinase 1 (TAK1), and TAK1 binding protein 1 (TAB1), thus avoiding an excessive inflammatory response. Furthermore, we demonstrate that miR-132 modulates the inflammatory response through a TRAF6-, TAK1-, and TAB1-mediated NF-κB signaling pathway. These results collectively reveal that miR-132 plays a negative regulatory role in the host antibacterial immune response, which will help to gain insight into the intricate network of host resistance to pathogen infection in lower vertebrates.

CircZKSCAN1 Suppresses Hepatocellular Carcinoma Tumorigenesis by Regulating miR-873-5p/Downregulation of Deleted in Liver Cancer 1

BACKGROUND

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-associated mortality worldwide. CircZKSCAN1 (hsa_circ_0001727) was reported to be related to HCC development. The present study aims to elucidate the potential role and molecular mechanism of circZKSCAN1 in the regulation of HCC progression.

METHODS

CircZKSCAN1, miR-873-5p, and downregulation of deleted in liver cancer 1 (DLC1) in HCC tissues and cells were detected by RT-qPCR. Correlation between circZKSCAN1 expression and overall survival rate was measured by Kaplan-Meier survival analysis. The effects of circZKSCAN1, miR-873-5p, and DLC1 on proliferation, migration, and invasion were analyzed by CCK-8 and transwell assays, respectively. CyclinD1, Matrix metalloproteinase (MMP)-9, MMP-2, and DLC1 in HCC cells were detected by Western blot assay. The binding relationship between miR-873-5p and circZKSCAN1 or DLC1 was predicted by the Circinteractome or Starbase, and then confirmed by dual-luciferase reporter assays, respectively. Tumor volume and tumor weight were measured in vivo.

RESULTS

CircZKSCAN1 was downregulated in HCC tissues and cells. Kaplan-Meier survival analysis suggested that there was a positive correlation between circZKSCAN1 expression and overall survival rate. Functionally, circZKSCAN1 blocked proliferation, migration, and invasion of HCC cells. MiR-873-5p was a target miRNA of circZKSCAN1, and miR-873-5p directly bound with DLC1. Rescue experiments confirmed that miR-873-5p overexpression or DLC1 knockdown attenuated the suppressive effects of circZKSCAN1 on HCC tumor growth in vitro. Besides, circZKSCAN1 inhibited HCC cell growth in vivo.

CONCLUSIONS

This study firstly revealed that circZKSCAN1 curbed HCC progression via modulating miR-873-5p/DLC1 axis, providing a potential therapeutic target for HCC treatment.

The Rapidly Expanding Nexus of Immunoglobulin G N-Glycomics, Suboptimal Health Status, and Precision Medicine

Immunoglobulin G is a prevalent glycoprotein, whose downstream immune responses are partially mediated by the N-glycans within the fragment crystallisable domain. Collectively termed the N-glycome, it is considered a complex intermediate phenotype: an amalgamation of genetic predisposition, environmental exposure, and health behaviours over the life-course. Thus, the immunoglobulin G N-glycome may provide an indication of health status on the spectrum from health to disease and infirmary. Although variability exists within and between populations, composition of the immunoglobulin G N-glycome remains stable over short periods of time. This underscores the potential of harnessing the immunoglobulin G N-glycome as an ideal tool for preclinical disease risk prediction, stratification, and prognosis through the development of precise dynamic biomarkers.

MiR-873-5p: A Potential Molecular Marker for Cancer Diagnosis and Prognosis

miR-873 is a microRNA located on chromosome 9p21.1. miR-873-5p and miR-873-3p are the two main members of the miR-873 family. Most studies focus on miR-873-5p, and there are a few studies on miR-873-3p. The expression level of miR-873-5p was down-regulated in 14 cancers and up-regulated in 4 cancers. miR-873-5p has many targeted genes, which have unique molecular functions such as catalytic activity, transcription regulation, and binding. miR-873-5p affects cancer development through the PIK3/AKT/mTOR, Wnt/β-Catenin, NF-κβ, and MEK/ERK signaling pathways. In addition, the target genes of miR-873-5p are closely related to the proliferation, apoptosis, migration, invasion, cell cycle, cell stemness, and glycolysis of cancer cells. The target genes of miR-873-5p are also related to the efficacy of several anti-cancer drugs. Currently, in cancer, the expression of miR-873-5p is regulated by a variety of epigenetic factors. This review summarizes the role and mechanism of miR-873-5p in human tumors shows the potential value of miR-873-5p as a molecular marker for cancer diagnosis and prognosis.

MicroRNA-29b-3p promotes 5-fluorouracil resistance <em>via</em> suppressing TRAF5-mediated necroptosis in human colorectal cancer

Drug resistance in colorectal cancer is a great challenge in clinic. Elucidating the deep mechanism underlying drug resistance will bring much benefit to diagnosis, therapy and prognosis in patients with colorectal cancer. In this study, miR-29b-3p was shown to be involved in resistance to 5-fluorouracil (5-FU)-induced necroptosis of colorectal cancer. Further, miR-29b-3p was shown to target a regulatory subunit of necroptosis TRAF5. Rescue of TRAF5 could reverse the effect of miR-29b-3p on 5-FU-induced necroptosis, which was consistent with the role ofnecrostatin-1 (a specific necroptosis inhibitor). Then it was demonstrated that miR-29b-3p was positively correlated with chemo-resistance in colorectal cancer while TRAF5 negatively. In conclusion, it is deduced that miR-29b-3p/TRAF5 signaling axis plays critical role in drug resistance in chemotherapy for colorectal cancer patients by regulating necroptosis. The findings in this study provide us a new target for interfere therapy in colorectal cancer.

HP1BP3 promotes tumor growth and metastasis by upregulating miR-23a to target TRAF5 in esophageal squamous cell carcinoma

HP1BP3, an ubiquitously expressed nuclear protein belonging to the H1 histone family of proteins, plays an important role in cell growth and viability. Recently, it was reported that HP1BP3 exclusively regulates miRNA biogenesis by enhancing transcriptional miRNA processing. Although HP1BP3 has previously been implicated in common cancer types, the mechanistic functions and effects of HP1BP3 and its role in the prognosis of esophageal squamous cell carcinoma (ESCC) remain unclear. Here, we report that ESCC tissues and cell lines show increased endogenous expression of HP1BP3. Knockdown of HP1BP3 in TE-1 cells significantly inhibited tumor growth and metastasis in vivo emphasizing its role in cell proliferation and invasion. In contrast, overexpression of HP1BP3 significantly enhanced tumor growth and metastasis in Eca-109 cells. Further, we found that HP1BP3 regulates these functions by upregulating miR-23a, which directly binds to the 3'UTR region of TRAF5 downstream to alter cell survival and proliferation. Our findings describe a role for HP1BP3 in promoting tumor growth and metastasis by upregulating miR-23a to target TRAF5 in esophageal cancer. This study provides novel insights into the potential of targeting miRNAs for therapy and as clinical markers for cancer progression.

Prognostic Significance of Autophagy-Relevant Gene Markers in Colorectal Cancer

Background

Colorectal cancer (CRC) is a common malignant solid tumor with an extremely low survival rate after relapse. Previous investigations have shown that autophagy possesses a crucial function in tumors. However, there is no consensus on the value of autophagy-associated genes in predicting the prognosis of CRC patients. This work screens autophagy-related markers and signaling pathways that may participate in the development of CRC, and establishes a prognostic model of CRC based on autophagy-associated genes.

Methods

Gene transcripts from the TCGA database and autophagy-associated gene data from the GeneCards database were used to obtain expression levels of autophagy-associated genes, followed by Wilcox tests to screen for autophagy-related differentially expressed genes. Then, 11 key autophagy-associated genes were identified through univariate and multivariate Cox proportional hazard regression analysis and used to establish prognostic models. Additionally, immunohistochemical and CRC cell line data were used to evaluate the results of our three autophagy-associated genes EPHB2, NOL3, and SNAI1 in TCGA. Based on the multivariate Cox analysis, risk scores were calculated and used to classify samples into high-risk and low-risk groups. Kaplan-Meier survival analysis, risk profiling, and independent prognosis analysis were carried out. Receiver operating characteristic analysis was performed to estimate the specificity and sensitivity of the prognostic model. Finally, GSEA, GO, and KEGG analysis were performed to identify the relevant signaling pathways.

Results

A total of 301 autophagy-related genes were differentially expressed in CRC. The areas under the 1-year, 3-year, and 5-year receiver operating characteristic curves of the autophagy-based prognostic model for CRC were 0.764, 0.751, and 0.729, respectively. GSEA analysis of the model showed significant enrichment in several tumor-relevant pathways and cellular protective biological processes. The expression of EPHB2, IL-13, MAP2, RPN2, and TRAF5 was correlated with microsatellite instability (MSI), while the expression of IL-13, RPN2, and TRAF5 was related to tumor mutation burden (TMB). GO analysis showed that the 11 target autophagy genes were chiefly enriched in mRNA processing, RNA splicing, and regulation of the mRNA metabolic process. KEGG analysis showed enrichment mainly in spliceosomes. We constructed a prognostic risk assessment model based on 11 autophagy-related genes in CRC.

Conclusion

A prognostic risk assessment model based on 11 autophagy-associated genes was constructed in CRC. The new model suggests directions and ideas for evaluating prognosis and provides guidance to choose better treatment strategies for CRC.

circFAT1(e2) Promotes Papillary Thyroid Cancer Proliferation, Migration, and Invasion via the miRNA-873/ZEB1 Axis

Circular RNAs (circRNAs) play an extremely important regulatory role in the occurrence and development of various malignant tumors including papillary thyroid cancer (PTC). circFAT1(e2) is a new type of circRNA derived from exon 2 of the FAT1 gene, which is distributed in the cytoplasm and nucleus of PTC cells. However, so far, the role of circFAT1(e2) in PTC is still unclear. In this study, circFAT1(e2) was found to be highly expressed in PTC cell lines and tissues. circFAT1(e2) knockdown suppressed PTC cell growth, migration, and invasion. Also, circFAT1(e2) acted as a sponge for potential microRNAs (miRNAs) to modulate cancer progression. A potential miRNA target was discovered to be miR-873 which was targeted by circFAT1(e2) in PTC. The dual-luciferase assay conducted later also confirmed that there was indeed a direct interaction between circFAT1(e2) and miR-873. This study also confirmed that circFAT1(e2) inhibited the miR-873 expression and thus promoted the ZEB1 expression, thus affecting the proliferation, metastasis, and invasion of PTC cells. In conclusion, the results of this study indicated that circFAT1(e2) played a carcinogenic role by targeting the miR-873/ZEB1 axis to promote PTC invasion and metastasis, which might become a potential novel target for therapy of PTC.

Transcriptional Factor Yin Yang 1 Promotes the Stemness of Breast Cancer Cells by Suppressing miR-873-5p Transcriptional Activity

Transcription factor Yin Yang 1 (YY1) is upregulated in multiple tumors and plays essential roles in tumor proliferation and metastasis. However, the function of YY1 in breast cancer stemness remains unclear. Herein, we found that YY1 expression was negatively correlated with the overall survival and relapse-free survival of breast cancer patients and positively correlated with the expression of stemness markers in breast cancer. Overexpression of YY1 increased the expression of stemness markers, elevated CD44+CD24- cell sub-population, and enhanced the capacity of cell spheroid formation and tumor-initiation. In contrast, YY1 knockdown exhibited the opposite effects. Mechanistically, YY1 decreased microRNA-873-5p (miR-873-5p) level by recruiting histone deacetylase 4 (HDAC4) and HDAC9 to miR-873-5p promoter and thus increasing the deacetylation level of miR-873-5p promoter. Sequentially, YY1 activated the downstream PI3K/AKT and ERK1/2 pathways, which have been confirmed to be suppressed by miR-873-5p in our recent work. Moreover, the suppressed effect of YY1/miR-873-5p axis on the stemness of breast cancer cells was partially dependent on PI3K/AKT and ERK1/2 pathways. Finally, it was found that the YY1/miR-873-5p axis is involved in the chemoresistance of breast cancer cells. Our study defines a novel YY1/miR-873-5p axis responsible for the stemness of breast cancer cells.

TNNT1, negatively regulated by miR-873, promotes the progression of colorectal cancer

BACKGROUND

Troponin T1 (TNNT1) is a subunit of troponin that has been linked to neuromuscular disorder. Recently, it was reported that TNNT1 facilitates the proliferation of breast cancer cells. Interestingly, Cancer Genome Atlas data indicate that its overexpression is associated with an unfavorable prognosis of colorectal cancer (CRC) patients. The present study aimed to explore the expression, function and mechanism of dysregulation of TNNT1 in CRC.

METHODS

Immunohistochemical staining and a real-time polymerase chain reaction were used to compare the expression level of TNNT1 in CRC tissues and adjacent tissues. Western blotting was used to detect the expression of TNNT1 in cell lines. Kaplan-Meier analysis and a chi-squared test were applied to evaluate the potential of TNNT1 to function as a cancer biomarker. RNA interference was used to inhibit TNNT1 expression in CRC cells, followed by detection of cell proliferation, apoptosis, migration and invasion. A luciferase reporter gene assay was used to determine the regulatory relationship between miR-873 and TNNT1.

RESULTS

In the present study, we found that TNNT1 was significantly up-regulated in CRC samples and cell lines. The up-regulation of TNNT1 was also associated with several clinicopathologic features, and its high expression was correlated with an unfavorable prognosis of the patients. Knockdown of TNNT1 markedly arrested proliferation, migration and invasion, whereas it also promoted apoptosis. TNNT1 was identified as a target gene of miR-873, and there was a negative correlation among CRC samples.

CONCLUSIONS

In conclusion, we have demonstrated that TNNT1, regulated by miR-873, is an oncogene of CRC associated with patient prognosis.

miR-141-3p and TRAF5 Network Contributes to the Progression of T-Cell Acute Lymphoblastic Leukemia

Numerous lines of evidence have shown that microRNAs (miRNAs) play a vital role in regulating the progression in many types of cancers, including T cell acute lymphoblastic leukemia (T-ALL). In this study, the potential underlying mechanism and functional role of miR-141-3p in T-ALL cells were determined. We found that the expression level of miR-141-3p was significantly downregulated, while that of tumor necrosis factor receptor-associated factor 5 (TRAF5) was strongly upregulated in tissues from patients with T-ALL compared with healthy controls. Subsequently, upregulation of miR-141-3p significantly repressed T-ALL cell proliferation and promoted cell apoptosis. Conversely, downregulation of miR-141-3p significantly inhibited cell apoptosis and enhanced T-ALL cell proliferation. We also verified that TRAF5 was the direct target of miR-141-3p in T-ALL cells. Additionally, TRAF5 overexpression significantly repressed cell apoptosis and increased T-ALL cell proliferation. In summary, miR-141-3p regulates T-ALL cell progression by directly targeting TRAF5, and may serve as a potential therapeutic target for T-ALL.

miRDRN-miRNA disease regulatory network: a tool for exploring disease and tissue-specific microRNA regulatory networks

BACKGROUND

MicroRNA (miRNA) regulates cellular processes by acting on specific target genes, and cellular processes proceed through multiple interactions often organized into pathways among genes and gene products. Hundreds of miRNAs and their target genes have been identified, as are many miRNA-disease associations. These, together with huge amounts of data on gene annotation, biological pathways, and protein-protein interactions are available in public databases. Here, using such data we built a database and web service platform, miRNA disease regulatory network (miRDRN), for users to construct disease and tissue-specific miRNA-protein regulatory networks, with which they may explore disease related molecular and pathway associations, or find new ones, and possibly discover new modes of drug action.

METHODS

Data on disease-miRNA association, miRNA-target association and validation, gene-tissue association, gene-tumor association, biological pathways, human protein interaction, gene ID, gene ontology, gene annotation, and product were collected from publicly available databases and integrated. A large set of miRNA target-specific regulatory sub-pathways (RSPs) having the form (T, G 1, G 2) was built from the integrated data and stored, where T is a miRNA-associated target gene, G 1 (G 2) is a gene/protein interacting with T (G 1). Each sequence (T, G 1, G 2) was assigned a p-value weighted by the participation of the three genes in molecular interactions and reaction pathways.

RESULTS

A web service platform, miRDRN (http://mirdrn.ncu.edu.tw/mirdrn/), was built. The database part of miRDRN currently stores 6,973,875 p-valued RSPs associated with 116 diseases in 78 tissue types built from 207 diseases-associated miRNA regulating 389 genes. miRDRN also provides facilities for the user to construct disease and tissue-specific miRNA regulatory networks from RSPs it stores, and to download and/or visualize parts or all of the product. User may use miRDRN to explore a single disease, or a disease-pair to gain insights on comorbidity. As demonstrations, miRDRN was applied: to explore the single disease colorectal cancer (CRC), in which 26 novel potential CRC target genes were identified; to study the comorbidity of the disease-pair Alzheimer's disease-Type 2 diabetes, in which 18 novel potential comorbid genes were identified; and, to explore possible causes that may shed light on recent failures of late-phase trials of anti-AD, BACE1 inhibitor drugs, in which genes downstream to BACE1 whose suppression may affect signal transduction were identified.

MicroRNA-873 inhibits the proliferation and invasion of endometrial cancer cells by directly targeting hepatoma-derived growth factor

An accumulation of evidence has demonstrated that abnormal microRNA (miRNA or miR) expression is associated with different types of cancer, including endometrial cancer (EC). The dysregulation of miRNAs may serve important roles in the development and progression of EC by regulating multiple aggressive biological behaviors, including cell proliferation, apoptosis, metastasis and angiogenesis. An in-depth understanding of the miRNAs associated with EC initiation and progression may be crucial for identifying successful therapeutic techniques. miR-873 has been demonstrated to be dysregulated in different types of cancer. However, the expression status and regulatory roles of miR-873 are yet to be elucidated in EC. In the present study, reverse transcription-quantitative PCR was carried out to detect miR-873 expression in EC tissues and cell lines. Cell Counting Kit-8 and in vitro invasion assays were utilized to determine the influence of miR-873 on the proliferation and invasion of EC cells. miR-873 expression was revealed to be downregulated in EC tissues and cell lines. Decreased miR-873 expression was significantly associated with International Federation of Gynecology and Obstetrics stage and lymph node metastasis of patients with EC. Functional assays revealed that resumed miR-873 expression suppressed the proliferation and invasion of EC cells. Additionally, hepatoma-derived growth factor (HDGF) was indicated to be a direct target gene of miR-873 in EC cells. HDGF was highly expressed in EC tissues and inversely correlated with miR-873 expression. HDGF silencing also imitated the tumor-suppressor activity of miR-873 overexpression in EC cells. A series of rescue experiments identified that recovered HDGF expression hindered the anti-proliferative and anti-invasive roles of miR-873 upregulation in EC cells. In conclusion, the present study indicated that miR-873 serves an important role as a tumor suppressor in EC development by directly targeting HDGF. The results may provide a novel insight into clinical treatments, which can be used to prevent EC aggression.

Upregulation of miR-29b-3p protects cardiomyocytes from hypoxia-induced apoptosis by targeting TRAF5

Background

MicroRNAs (miRNAs) are pivotal regulators in regulating hypoxia-induced cardiomyocyte injury. This study was designed to evaluate the effects of miR-29b-3p on hypoxic cardiomyocytes.

Methods

Human AC16 cells were cultured under normoxic or hypoxic conditions. Hypoxic injury was confirmed based on alterations in cell viability using CCK-8 assay and apoptosis using flow cytometry and Hoechst staining. Bioinformatics analyses and the dual-luciferase reporter assay were performed to predict and validate the target gene of miR-29b-3p.

Results

We found that hypoxia suppressed cell viability and promoted apoptosis. TNF receptor-associated factor 5 (TRAF5) was a potential target gene of miR-29b-3p. Our in vitro experiments revealed that miR-29b-3p overexpression or TRAF6 knockdown significantly protected cardiomyocytes against hypoxia-induced injury. Moreover, knockdown of TRAF5 knockdown potentiated the protective effects of miR-29b-3p against hypoxia-induced cell injury.

Conclusion

These findings suggest that upregulation of miR-29b-3p could protect cardiomyocytes against hypoxia-induced injury through downregulation of TRAF5. Targeting TRAF5 with miR-29b-3p might be a potential therapeutic method for AMI.

The Modulatory Role of MicroRNA-873 in the Progression of KRAS-Driven Cancers

KRAS is one of the most frequently mutated proto-oncogenes in pancreatic ductal adenocarcinoma (PDAC) and aberrantly activated in triple-negative breast cancer (TNBC). A profound role of microRNAs (miRNAs) in the pathogenesis of human cancer is being uncovered, including in cancer therapy. Using in silico prediction algorithms, we identified miR-873 as a potential regulator of KRAS, and we investigated its role in PDAC and TNBC. We found that reduced miR-873 expression is associated with shorter patient survival in both cancers. miR-873 expression is significantly repressed in PDAC and TNBC cell lines and inversely correlated with KRAS levels. We demonstrate that miR-873 directly bound to the 3′ UTR of KRAS mRNA and suppressed its expression. Notably, restoring miR-873 expression induced apoptosis; recapitulated the effects of KRAS inhibition on cell proliferation, colony formation, and invasion; and suppressed the activity of ERK and PI3K/AKT, while overexpression of KRAS rescued the effects mediated by miR-873. Moreover, in vivo delivery of miR-873 nanoparticles inhibited KRAS expression and tumor growth in PDAC and TNBC tumor models. In conclusion, we provide the first evidence that miR-873 acts as a tumor suppressor by targeting KRAS and that miR-873-based gene therapy may be a therapeutic strategy in PDAC and TNBC.

miR-106b-5p inhibits the invasion and metastasis of colorectal cancer by targeting CTSA

Background

Although miR-106b-5p has been reported to play a pivotal role in various human malignancies, its role in colorectal cancer (CRC) remains unknown. In this study, we comprehensively investigated miR-106b-5p expression and biologic functions in CRC and the molecular mechanism involved.

Patients and methods

miR-106b-5p expression was detected in CRC tissues and cell lines by quantitative reverse transcription-polymerase chain reaction. The effects of miR-106b-5p on metastasis were determined in vitro using transwell assays, and in vivo effects were evaluated using a mouse tail vein injection model. Downstream targets of miR-106b-5p were confirmed using bioinformatics programs, luciferase assays, and rescue experiments. Target gene expression and clinicopathologic parameters were also analyzed.

Results

miR-106b-5p expression was lower in CRC tissues than in corresponding nontumorous tissues (P=0.009), and miR-106b-5p downregulation was negatively associated with lymph node metastasis (P=0.006). Functional assays demonstrated that miR-106b-5p overexpression suppressed CRC cell migration and invasion in vitro and lung metastasis formation in vivo. In addition, luciferase assays confirmed that miR-106b-5p directly bound to the 3' untranslated region of cathepsin A (CTSA) and that miR-106b-5p suppressed CRC cell migration and invasion by targeting CTSA. Clinicopathologic analysis showed that CTSA was significantly upregulated in CRC, and increased CTSA was negatively associated with lymph node metastasis (P=0.012).

Conclusion

Our findings revealed that miR-106b-5p inhibits CRC metastasis by upregulating CTSA expression, which may lead to novel therapeutic strategies for CRC patients.