MiR-511 inhibits growth and metastasis of human hepatocellular carcinoma cells by targeting PIK3R3

MicroRNA as Key Players in Hepatocellular Carcinoma: Insights into Their Role in Metastasis

Liver cancer or hepatocellular carcinoma (HCC) remains the most common cancer in global epidemiology. Both the frequency and fatality of this malignancy have shown an upward trend over recent decades. Liver cancer is a significant concern due to its propensity for both intrahepatic and extrahepatic metastasis. Liver cancer metastasis is a multifaceted process characterized by cell detachment from the bulk tumor, modulation of cellular motility and invasiveness, enhanced proliferation, avoidance of the immune system, and spread either via lymphatic or blood vessels. MicroRNAs (miRNAs) are small non-coding ribonucleic acids (RNAs) playing a crucial function in the intricate mechanisms of tumor metastasis. A number of miRNAs can either increase or reduce metastasis via several mechanisms, such as control of motility, proliferation, attack by the immune system, cancer stem cell properties, altering the microenvironment, and the epithelial-mesenchymal transition (EMT). Besides, two other types of non-coding RNAs, such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) can competitively bind to endogenous miRNAs. This competition results in the impaired ability of the miRNAs to inhibit the expression of the specific messenger RNAs (mRNAs) that are targeted. Increasing evidence has shown that the regulatory axis comprising circRNA/lncRNA-miRNA-mRNA is correlated with the regulation of HCC metastasis. This review seeks to present a thorough summary of recent research on miRNAs in HCC, and their roles in the cellular processes of EMT, invasion and migration, as well as the metastasis of malignant cells. Finally, we discuss the function of the lncRNA/circRNA-miRNA-mRNA network as a crucial modulator of carcinogenesis and the regulation of signaling pathways or genes that are relevant to the metastasis of HCC. These findings have the potential to offer valuable insight into the discovery of novel therapeutic approaches for management of liver cancer metastasis.

Assessment of circulating levels of microRNA-326, microRNA-424, and microRNA-511 as biomarkers for hepatocellular carcinoma in Egyptians

BACKGROUND

Hepatocellular carcinoma (HCC) is the fifth most common cancer. Differential expression of microRNAs (miRNAs)-326, miRNA-424, and miRNA-511 has been associated with the diagnosis and prognosis of HCC in different populations. However, limited information is available regarding their expression in Egyptian HCC patients.

AIM

To assess the role of circulating miRNAs-326, miRNA-424, and miRNA-511 in Egyptian HCC patients.

METHODS

This prospective observational study included 70 HCC patients and 25 healthy controls. The circulating levels of these three miRNAs were evaluated by real-time PCR. Receiver operating characteristic curve analysis was used to test the diagnostic accuracy of microRNA expression levels.

RESULTS

All miRNAs were differentially expressed in HCC patients; miRNAs326 and miRNA-424 were upregulated, while miRNA-511 was downregulated. Both miRNA-326 and miRNA-424 showed sensitivity and specificity of 97%, 71.4%, and 52%, 60%, respectively, to differentiate HCC from controls. Moreover, miRNA-326 was associated with survival and could differentiate between Child grades (A vs B); miRNA-424 significantly differentiated early vs intermediate stages of HCC; while miRNA-511 was significantly correlated with response to modified Response Evaluation Criteria in Solid Tumors (mRECIST).

CONCLUSION

We conclude that miRNA-326, miRNA-424, and miRNA-511 have diagnostic and prognostic roles in Egyptian patients with hepatitis C virus-related HCC and should be considered for better disease management.

The Computational Analysis of Single Nucleotide Associated with MicroRNA Affecting Hepatitis B Infection

BACKGROUND

MicroRNAs (miRNAs) have a pivotal role in Hepatitis B Virus (HBV) infection and its complications by targeting the cellular transcription factors required for gene expression or directly binding to HBV transcripts. Single Nucleotide Polymorphisms (SNPs) in miRNA genes affect their expression and the regulation of target genes, clinical course, diagnosis, and therapeutic interventions of HBV infection.

METHODS

Computational assessment and cataloging of miRNA gene polymorphisms targeting mRNA transcripts straightly or indirectly through the regulation of hepatitis B infection by annotating the functional impact of SNPs on mRNA-miRNA and miRNA-RBS (miRNA binding sites) interaction were screened by applying various universally available datasets such as the miRNA SNP3.0 software.

RESULTS

2987 SNPs were detected in 139 miRNAs affecting hepatitis B infection. Among them, 313 SNPs were predicted to have a significant role in the progression of hepatitis B infection. The computational analysis also revealed that 45 out of the 313 SNPs were located in the seed region and were more important than others. Has-miR-139-3p had the largest number of SNPs in the seed region (n=6). On the other hand, proteoglycans in cancer, adherens junction, lysine degradation, NFkappa B signaling cascade, ECM-receptor binding, viral carcinogenesis, fatty acid metabolism, TGF-beta signaling pathway, p53 signaling pathway, immune evasion related pathways, and fatty acid biosynthesis were the most important pathways affected by these 139 miRNAs.

CONCLUSION

The results revealed 45 SNPs in the seed region of 25 miRNAs as the catalog in miRNA genes that regulated the hepatitis B infection. The results also showed the most important pathways regulated by these miRNAs that can be targeted for therapeutic purposes.

PIK3R3, part of the regulatory domain of PI3K, is upregulated in sarcoma stem-like cells and promotes invasion, migration, and chemotherapy resistance

To identify drivers of sarcoma cancer stem-like cells (CSCs), we compared gene expression using RNA sequencing between HT1080 fibrosarcoma and SK-LMS-1 leiomyosarcoma spheroids (which are enriched for CSCs) compared with the parent populations. The most overexpressed survival signaling-related gene in spheroids was phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3), a regulatory subunit of PI3K, which functions in tumorigenesis and metastasis. In a human sarcoma microarray, PIK3R3 was also overexpressed by 4.1-fold compared with normal tissues. PIK3R3 inhibition using shRNA in the HT1080, SK-LMS-1, and DDLS8817 dedifferentiated liposarcoma in spheroids and in CD133+ cells (a CSC marker) reduced expression of CD133 and the stem cell factor Nanog and blocked spheroid formation by 61-71%. Mechanistic studies showed that in spheroid cells, PIK3R3 activated AKT and ERK signaling. Inhibition of PIK3R3, AKT, or ERK using shRNA or inhibitors decreased expression of Nanog, spheroid formation by 68-73%, and anchorage-independent growth by 76-91%. PIK3R3 or ERK1/2 inhibition similarly blocked sarcoma spheroid cell migration, invasion, secretion of MMP-2, xenograft invasion into adjacent normal tissue, and chemotherapy resistance. Together, these results show that signaling through the PIK3R3/ERK/Nanog axis promotes sarcoma CSC phenotypes such as migration, invasion, and chemotherapy resistance, and identify PIK3R3 as a potential therapeutic target in sarcoma.

MiR-513b-5p represses autophagy during the malignant progression of hepatocellular carcinoma by targeting PIK3R3

Hepatocellular carcinoma (HCC) serves as a prevailing global malignancy with severe mortality and extremely unsatisfactory prognosis, in which autophagy is a fundamental process in liver cancer pathogenesis, but the mechanisms are poorly understood. MicroRNAs (miRNAs) serve as a type of well-recognized non-coding regulators and contribute to the modulation of liver cancer development, from the aspects of diagnosis, progression, and therapy. Here, we aimed to investigate the function of hsa_microRNA-513b-5p (miR-513b-5p) in regulating autophagy during HCC progression. Specifically, our data showed that miR-513b-5p mimic reduced the LC3-II and beclin1 expression but enhanced p62 expression in HCC cells. MiR-513b-5p repressed liver cancer cell proliferation, migration/invasion, and induced apoptosis in vitro. Crucially, miR-513b-5p attenuated tumor growth of liver cancer cells in vivo. In the mechanical investigation, we identified that PIK3R3 mRNA 3′UTR was targeted by miR-513b-5p and miR-513b-5p suppressed PIK3R3 expression. PIK3R3 overexpression partly reversed miR-513b-5p-mediated autophagy, proliferation, and apoptosis of liver cancer cells. Consequently, we concluded that miR-513b-5p repressed autophagy during the malignant progression of HCC by targeting PIK3R3. MiR-513b-5p may be applied as a therapeutic target for HCC.

Long non-coding RNA 01559 mediates the malignant phenotypes of hepatocellular carcinoma cells through targeting miR-511

BACKGROUND

Long non-coding RNA 01559 (LINC01559) has been found to be associated with the tumorigenesis of malignant tumors. However, the expression pattern and the potential molecular mechanism of LINC01559 in hepatocellular carcinoma (HCC) progression remain unclear.

METHODS

Expression profile and clinical data of patients with HCC were retrieved from The Cancer Genome Atlas database. The quantitative real-time PCR (qRT-PCR) and western blot assays were used to detect the mRNA and protein levels of indicated molecules. Loss-of-function of LINC01559 and microRNA-511 (miR-511) assays were implemented to validate their roles in regulating proliferation, invasion and migration of HCC HepG2 and Huh7 cells. Bioinformatics and luciferase reporter assays were used to determine the possible interactions between LINC01559, miR-511 and solute carrier family 38 member 1 (SLC38A1).

RESULTS

LINC01559 was highly expressed, and related to poor prognosis in HCC patients. LINC01559-knockdown restrained the proliferation and growth of HepG2 and Huh7 cells. Furthermore, LINC01559 can function as a sponge for miR-511, which was downregulated in HCC patients. Downregulation of miR-511 significantly increased the cell viability, invasive and migratory capacities, and could abolish the suppressive effect of LINC01559-knockdown on these HCC cells. Moreover, SLC38A1 was a target of miR-511 and upregulated in HCC. Knockdown of LINC01559 significantly reduced while miR-511 inhibitor notably elevated the mRNA and protein levels of SLC38A1, which were abrogated by downregulation of LINC01559 and miR-511 simultaneously.

CONCLUSIONS

LINC01559 functioned as a competitive endogenous RNA mediating the malignant phenotypes of HCC cells via sponging miR-511, and may be a considerable therapeutic bio-target in HCC.

Inhibition of protein kinase D by CID755673 promotes maintenance of the pluripotency of embryonic stem cells

The identification of novel mechanisms to maintain embryonic stem cell (ESC) pluripotency is of crucial importance, because the currently used culture conditions are not suitable for ESCs from all species. In this study, we show that the protein kinase D (PKD) inhibitor CID755673 (CID) is able to maintain the undifferentiated state of mouse ESCs in combination with the mitogen-activated protein kinase kinase (MEK) inhibitor. The expression levels of PKD members, including PKD1, PKD2 and PKD3, were low in mouse ESCs but significantly increased under differentiation conditions. Therefore, depletion of three PKD genes was able to phenocopy PKD inhibition. Mechanistically, PKD inhibition activated PI3K/AKT signaling by increasing the level of AKT phosphorylation, and the addition of a PI3K/AKT signaling pathway inhibitor partially reduced the cellular response to PKD inhibition. Importantly, the self-renewal-promoting effect of CID was maintained in human ESCs. Simultaneous knockdown of the three human PKD isoforms enabled short-term self-renewal in human ESCs, whereas PI3K/AKT signaling inhibition eliminated this self-renewal ability downstream of the PKD inhibitor. These findings expand our understanding of the gene regulatory network of ESC pluripotency.

RETRACTED: Long non-coding RNA LINC00160 functions as a decoy of microRNA-132 to mediate autophagy and drug resistance in hepatocellular carcinoma via inhibition of PIK3R3

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors. Following the publication of the above article, the authors found that “LINC00160 did not affect Atg5 and P65 protein expression in HCC cells, which was inconsistent with the result of this paper. Furthermore, we apologize to the readership of the Journal for any inconvenience caused.” Additionally, after publication, the journal was made aware of comments in relation to this article (https://pubpeer.com/publications/333AE65483683ADF50A723BE34AD62). The authors have not responded to our request to respond to these comments.

Long Non-Coding RNAs in Biliary Tract Cancer-An Up-to-Date Review

The term long non-coding RNA (lncRNA) describes non protein-coding transcripts with a length greater than 200 base pairs. The ongoing discovery, characterization and functional categorization of lncRNAs has led to a better understanding of the involvement of lncRNAs in diverse biological and pathological processes including cancer. Aberrant expression of specific lncRNA species was demonstrated in various cancer types and associated with unfavorable clinical characteristics. Recent studies suggest that lncRNAs are also involved in the development and progression of biliary tract cancer, a rare disease with high mortality and limited therapeutic options. In this review, we summarize current findings regarding the manifold roles of lncRNAs in biliary tract cancer and give an overview of the clinical and molecular consequences of aberrant lncRNA expression as well as of underlying regulatory functions of selected lncRNA species in the context of biliary tract cancer.

MiR-511 mimic transfection inhibits the proliferation, invasion of osteosarcoma cells and reduces metastatic osteosarcoma tumor burden in nude mice via targeting MAPK1

Osteosarcoma, a highly aggressive cancer, can rapidly metastasize to distant organs such as lung, liver, brain. Despite much progress in the therapeutic regime has been made, the prognosis of osteosarcoma remains poor. In present study, microRNA-511 (miR-511) is lowly expressed in osteosarcoma cells, including MG63, U-2 OS, Saos-2 cells, while mitogen activated protein kinase1 (MAPK1) is highly expressed in osteosarcoma cells. Interestingly, MAPK1 might be a target of miR-511. We found that overexpression of miR-511 by miR-511 mimic transfection may result to low expression of MAPK1. Further study showed that miR-511 mimic inhibits the development of osteosarcoma MG63 cell, including proliferation and invasion. Moreover, miR-511 mimic transfection reduces metastatic osteosarcoma tumor burden in nude mice. These activities are mediated by targeting MAPK1. Our study provides a new sight for the molecular pathogenesis of osteosarcoma.

circZFR promotes cell proliferation and migration by regulating miR-511/AKT1 axis in hepatocellular carcinoma

BACKGROUND

Emerging data suggest the crucial regulatory roles of circular RNAs (circRNAs) in hepatocellular carcinoma (HCC). However, the pathophysiology role of circZFR in HCC remains largely unknown.

AIMS

This study aims to disclose the functions of circZFR in HCC progression and its potential molecular mechanism.

METHODS

circZFR and miR-511 were identified by qRT-PCR. Colony formation assay, wound-healing assay, transwell assay, and flow cytometry assay were performed to determine the cell proliferation, migration, invasion and apoptosis. Western blotting and immunohistochemistry (IHC) were utilized to evaluate the expression level of AKT1, GSK3β, β-catenin and cascades of proliferation-related proteins both in vitro and in vivo. Dual luciferase reporter assay was conducted to evaluate the interactions among circZFR, miR-511 and AKT1.

RESULTS

The expression of circZFR was enhanced and the expression of miR-511 was down-regulated in HCC tissues and cells. Functionally, circZFR silencing or miR-511 overexpression suppressed cell proliferation, migration and invasion, and induced apoptosis of HCC cells. Mechanistically, circZFR acted as a miR-511 sponge to up-regulate its target gene AKT1, which activated cascades of proliferation-related proteins (c-Myc, cyclin D1, Survivin and Bcl-2). Furthermore, depletion of circZFR inhibited tumorigenesis and decreased the expression level of AKT1 in xenograft models.

CONCLUSION

circZFR promotes HCC progression by directly down-regulating miR-511 to activate AKT1 signaling, suggesting that circZFR is a potential target in HCC treatment. Targeting circZFR may provide therapeutic benefits for HCC.

Edwardsiella tarda-induced miR-7a functions as a suppressor in PI3K/AKT/GSK3β signaling pathway by targeting insulin receptor substrate-2 (IRS2a and IRS2b) in Paralichthys olivaceus

To study the effect of Edwardsiella tarda infection on miRNAs expression profile in Japanese flounder, fish were injected intraperitoneally with E. tarda. The miRNAs involved in regulating immune responses were analyzed by high-throughput sequencing. A total of 164 mature miRNAs were identified, of which 17 miRNAs were differentially expressed (DE miRNAs) after E. tarda infection, indicating that they were immune-related miRNAs. To further examine the relationship between the miRNAs and their predicted target mRNAs, a total of 22 predicted target mRNAs, mainly related to endocytic signaling pathway, NF-κB signaling pathway, and p53 signaling pathway, were detected with miRNA mimics in HEK-293T cells by dual-luciferase reporter experiments. Finally, we confirmed that insulin receptor substrate-2 (IRS2a and IRS2b) were regulated by miR-7a. And the target sites of the 3' untranslated region (UTR) of IRS2a and IRS2b were verified by dual-luciferase reporter experiments. Furthermore, we found that the E. tarda and LPS significantly increased host miR-7a expression. In vivo and in vitro studies revealed that IRS2-mediated PI3K/AKT/GSK3β signaling pathway was suppressed. Taken together, these results implied that miR-7a might be a key regulator of PI3K/AKT/GSK3β signaling pathway via suppressing the IRS2a and IRS2b genes.

Identification of key candidate genes involved in melanoma metastasis

Metastasis is the most lethal stage of cancer progression. The present study aimed to investigate the underlying molecular mechanisms of melanoma metastasis using bioinformatics. Using the microarray dataset GSE8401 from the Gene Expression Omnibus database, which included 52 biopsy specimens from patients with melanoma metastasis and 31 biopsy specimens from patients with primary melanoma, differentially expressed genes (DEGs) were identified, subsequent to data preprocessing with the affy package, followed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. A protein-protein interaction (PPI) network was constructed. Mutated genes were analyzed with 80 mutated cases with melanoma from The Cancer Genome Atlas. The overall survival of key candidate DEGs, which were within a filtering of degree >30 criteria in the PPI network and involved three or more KEGG signaling pathways, and genes with a high mutation frequency were delineated. The expression analysis of key candidate DEGs, mutant genes and their associated genes were performed on UALCAN. Of the 1,187 DEGs obtained, 505 were upregulated and 682 were downregulated. ‘Extracellular exosome’ processes, the ‘amoebiasis’ pathway, the ‘ECM-receptor interaction’ pathway and the ‘focal adhesion’ signaling pathway were significantly enriched and identified as important processes or signaling pathways. The overall survival analysis of phosphoinositide-3-kinase regulator subunit 3 (PIK3R3), centromere protein M (CENPM), aurora kinase A (AURKA), laminin subunit α 1 (LAMA1), proliferating cell nuclear antigen (PCNA), adenylate cyclase 1 (ADCY1), BUB1 mitotic checkpoint serine/threonine kinase (BUB1), NDC80 kinetochore complex component (NDC80) and protein kinase C α (PRKCA) in DEGs was statistically significant. Mutation gene analysis identified that BRCA1-associated protein 1 (BAP1) had a higher mutation frequency and survival analysis, and its associated genes in the BAP1-associated PPI network, including ASXL transcriptional regulator 1 (ASXL1), proteasome 26S subunit, non-ATPase 3 (PSMD3), proteasome 26S subunit, non ATPase 11 (PSMD11) and ubiquitin C (UBC), were statistically significantly associated with the overall survival of patients with melanoma. The expression levels of PRKCA, BUB1, BAP1 and ASXL1 were significantly different between primary melanoma and metastatic melanoma. Based on the present study, ‘extracellular exosome’ processes, ‘amoebiasis’ pathways, ‘ECM-receptor interaction’ pathways and ‘focal adhesion’ signaling pathways may be important in the formation of metastases from melanoma. The involved genes, including PIK3R3, CENPM, AURKA, LAMA1, PCNA, ADCY1, BUB1, NDC80 and PRKCA, and mutation associated genes, including BAP1, ASXL1, PSMD3, PSMD11 and UBC, may serve important roles in metastases of melanoma.

Mechanism of miR-137 regulating migration and invasion of melanoma cells by targeting PIK3R3 gene

OBJECTIVE

To investigate the effect of microRNA-137 (miR-137) on the migration and invasion of melanoma cells and its mechanism.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-137 in melanoma tissues and cells. miR-137 mimics, phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) small interfering RNA and corresponding controls were transfected into A375 and WM451 cells by lipofection. The expression of PIK3R3 was examined by qRT-PCR and Western blot analysis. The Trans-well assay was conducted to measure cell migration and invasion. Dual luciferase reporter assay was used to detect the interaction between miR-137 and PIK3R3.

RESULTS

Compared with normal pigmented nevus tissue, miR-137 expression was significantly reduced in melanoma tissues. Compared with keratinous HaCaT cells, the level of miR-137 was significantly decreased in melanoma SK-MEL-1, A375, and WM451 cells. Knockdown of miR-137 significantly reduced the migrated and invasive abilities of melanoma A375 and WM451 cells. Moreover, inhibition of PIK3R3 obviously suppressed the migration and invasion abilities of melanoma A375 and WM451 cells. Luciferase activity assay showed that PIK3R3 was a direct target of miR-137. In addition, overexpression of miR-137-inhibited PIK3R3 expression, while knockdown of miR-137-enhanced PIK3R3 abundance. Restoration of PIK3R3 reversed the regulatory effect of miR-137 on cell migration and invasive in melanoma A375 and WM451 cells.

CONCLUSION

miR-137 inhibited melanoma cell migration and invasion by targeting PIK3R3 gene.

Targeting the mTOR regulatory network in hepatocellular carcinoma: Are we making headway?

The mechanistic target of rapamycin (mTOR) pathway coordinates organismal growth and homeostasis in response to growth factors, nutrients, and cellular energy stage. The pathway regulates several major cellular processes and is implicated in various pathological conditions, including hepatocellular carcinoma (HCC). This review summarizes recent advances of the mTOR pathway, highlights the potential of the mTOR pathway as a therapeutic target, and explores clinical trials targeting the mTOR pathway in HCC. Although the review focuses on the mTOR pathway involved in HCC, more comprehensive discussions (eg, developing a rational design for future trials targeting the mTOR pathway) are also applicable to other tumors.

MicroRNA‑601 serves as a potential tumor suppressor in hepatocellular carcinoma by directly targeting PIK3R3

Recently, microRNAs (miRNAs) have been acknowledged as important regulators of hepatocarcinogenesis and tumor progression. Therefore, identifying the underlying molecular mechanisms of miRNAs in the occurrence and development of hepatocellular carcinoma (HCC) may be important for understanding the pathogenesis of HCC and aid the identification of potential therapeutic strategies. In the present study, miRNA (miR)‑601 was significantly downregulated in HCC tissues and cell lines; low miR‑601 expression was strongly associated with tumor, node and metastasis staging and lymph node metastasis of patients with HCC. In addition, the overexpression of miR‑601 expression significantly inhibited the proliferation and invasion of HCC cells. Regarding the underlying mechanism, phosphoinositide‑3‑kinase regulatory subunit 3 (PIK3R3) was predicted to be a direct target of miR‑601 in HCC cells. Furthermore, restoration of PIK3R3 expression in these cells counteracted the inhibitory effects of miR‑601 on cell proliferation and invasion in HCC. Notably, miR‑601 overexpression inhibited the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway in HCC via the regulation of PIK3R3. Collectively, these results demonstrated that miR‑601 may inhibit the progression of HCC by directly targeting PIK3R3 and regulating the AKT/mTOR signaling pathway. Therefore, miR‑601 may be an effective therapeutic target for the treatment of patients with HCC.

The oncoprotein TBX3 is controlling severity in experimental arthritis

BACKGROUND

Development of autoimmune diseases is the result of a complex interplay between hereditary and environmental factors, with multiple genes contributing to the pathogenesis in human disease and in experimental models for disease. The T-box protein 3 is a transcriptional repressor essential during early embryonic development, in the formation of bone and additional organ systems, and in tumorigenesis.

METHODS

With the aim to find novel genes important for autoimmune inflammation, we have performed genetic studies of collagen-induced arthritis (CIA), a mouse experimental model for rheumatoid arthritis.

RESULTS

We showed that a small genetic fragment on mouse chromosome 5, including Tbx3 and three additional protein-coding genes, is linked to severe arthritis and high titers of anti-collagen antibodies. Gene expression studies have revealed differential expression of Tbx3 in B cells, where low expression was accompanied by a higher B cell response upon B cell receptor stimulation in vitro. Furthermore, we showed that serum TBX3 levels rise concomitantly with increasing severity of CIA.

CONCLUSIONS

From these results, we suggest that TBX3 is a novel factor important for the regulation of gene transcription in the immune system and that genetic polymorphisms, resulting in lower expression of Tbx3, are contributing to a more severe form of CIA and high titers of autoantibodies. We also propose TBX3 as a putative diagnostic biomarker for rheumatoid arthritis.

A miRNA signature suggestive of nodal metastases from laryngeal carcinoma

The discovery that miRNAs are frequently deregulated in tumours offers the opportunity to identify them as prognostic and diagnostic markers. The aim of this multicentric study is to identify a miRNA expression profile specific for laryngeal cancer. The secondary endpoint was to identify specific deregulated miRNAs with potential as prognostic biomarkers for tumour spread and nodal involvement, and specifically to search for a miRNA pattern pathognomonic for N+ laryngeal cancer and for N- tissues. We identified 20 miRNAs specific for laryngeal cancer and a tissue-specific miRNA signature that is predictive of lymph node metastases in laryngeal carcinoma characterised by 11 miRNAs, seven of which are overexpressed (upregulated) and four downregulated. These results allow the identification of a group of potential specific tumour biomarkers for laryngeal carcinoma that can be used to improve its diagnosis, particularly in early stages, as well as its prognosis.

Mir-1287 suppresses the proliferation, invasion, and migration in hepatocellular carcinoma by targeting PIK3R3

Mature microRNAs (miRNAs) are a class of small noncoding RNA molecules involved in regulation of post-translational gene expression. Although aberrant levels of miRNAs have been found in various tumor tissues, their importance in tumor development and the molecular basis of their regulatory role remain unclear. Our bioinformatic analysis on The Cancer Genome Atlas database and microarray-based comparison of miRNA in different cell lines revealed that the level of mir-1287 is suppressed in hepatocellular carcinoma (HCC) cells. When upregulated, mir-1287 can reduce the tumorigenesis phenotypes of HCC cells in several in vitro models. We further found that mir-1287 directly targets messenger RNA encoding PIK3R3, which is a tumor-promoting factor acting in several pathways linked to tumorigenesis. Our study suggests that aberrant suppression of mir-1287 is potentially responsible for the development of HCC, and miRNA-based strategies may be developed for efficient detection and treatment of HCC.

Genetic variants in PI3K/Akt/mTOR pathway genes contribute to gastric cancer risk

PI3K/Akt/mTOR pathway is involved in tumor initiation and progression, including gastric cancer (GC). However, the single nucleotide polymorphisms (SNPs) in this pathway and underlying molecular mechanism remain largely unexplored. A case-control study of 1275 GC patients and 1436 controls was performed to explore the associations of potentially functional SNPs in PI3K/Akt/mTOR pathway genes with the risk of GC. In the logistic regression analyses, one SNP rs7536272 out of the four candidate SNPs showed a significant association with GC risk (additive model: OR = 1.16, 95% CI = 1.03-1.30; co-dominant model: AG vs. AA, OR = 1.30, 95% CI = 1.11-1.53; dominant model: AG/GG vs. AA, OR = 1.28, 95% CI = 1.10-1.49).The luciferase assay indicated that rs7536272 G allele significantly enhanced the transcriptional activity, compared with A allele. Further expression quantitative trait loci (eQTL) analysis showed that GC patients with rs7536272 AG/GG genotypes had remarkably higher PIK3R3 levels than those with AA genotype, suggesting that rs7536272 polymorphism influenced the expression of PIK3R3. Additionally, we observed that GC patients with high expression of PIK3R3 had significant poorer outcome than those with low expression (HR = 1.29, 95% CI = 1.09-1.53). Our result demonstrated that SNP rs7536272, a functional risk variant located in the promoter region of PIK3R3, showed association with increased transcriptional activity and upregulation of PIK3R3 expression, thus involved in GC development.

Screening for susceptibility genes in hereditary non-polyposis colorectal cancer

In the present study, hereditary non-polyposis colorectal cancer (HNPCC) susceptibility genes were screened for using whole exome sequencing in 3 HNPCC patients from 1 family and using single nucleotide polymorphism (SNP) genotyping assays in 96 other colorectal cancer and control samples. Peripheral blood was obtained from 3 HNPCC patients from 1 family; the proband and the proband's brother and cousin. High-throughput sequencing was performed using whole exome capture technology. Sequences were aligned against the HAPMAP, dbSNP130 and 1,000 Genome Project databases. Reported common variations and synonymous mutations were filtered out. Non-synonymous single nucleotide variants in the 3 HNPCC patients were integrated and the candidate genes were identified. Finally, SNP genotyping was performed for the genes in 96 peripheral blood samples. In total, 60.4 Gb of data was retrieved from the 3 HNPCC patients using whole exome capture technology. Subsequently, according to certain screening criteria, 15 candidate genes were identified. Among the 96 samples that had been SNP genotyped, 92 were successfully genotyped for 15 gene loci, while genotyping for HTRA1 failed in 4 sporadic colorectal cancer patient samples. In 12 control subjects and 81 sporadic colorectal cancer patients, genotypes at 13 loci were wild-type, namely DDX20, ZFYVE26, PIK3R3, SLC26A8, ZEB2, TP53INP1, SLC11A1, LRBA, CEBPZ, ETAA1, SEMA3G, IFRD2 and FAT1. The CEP290 genotype was mutant in 1 sporadic colorectal cancer patient and was wild-type in all other subjects. A total of 5 of the 12 control subjects and 30 of the 81 sporadic colorectal cancer patients had a mutant HTRA1 genotype. In all 3 HNPCC patients, the same mutant genotypes were identified at all 15 gene loci. Overall, 13 potential susceptibility genes for HNPCC were identified, namely DDX20, ZFYVE26, PIK3R3, SLC26A8, ZEB2, TP53INP1, SLC11A1, LRBA, CEBPZ, ETAA1, SEMA3G, IFRD2 and FAT1.

miRNAs as potential regulators of mTOR pathway in renal cell carcinoma

Renal cell carcinoma (RCC) is the most commonly occurring solid cancer of the adult kidney with the majority of RCC cases being detected accidentally. The most aggressive subtype is clear cell RCC (ccRCC). miRNAs, a family of small noncoding RNAs regulating gene expression have been identified as key biological modulators. The von Hippel-Lindau pathway is one of the signaling pathways involved in the pathophysiology of ccRCC. Another oncogenic mechanism involves the activation of PI3K/AKT/mTOR signaling and serves as a central regulator of cell metabolism, proliferation and survival. Several studies have described the involvement of miRNA dysregulation in the pathogenesis and progression of ccRCC. These molecules can be considered as potential diagnostic and prognostic biomarkers, allowing response to therapy to be monitored.

Molecular mechanism for miR-350 in regulating of titanium dioxide nanoparticles in macrophage RAW264.7 cells

This study investigated the role of microRNA(miRNA) in regulating the cytotoxicity of TiO₂ nanoparticles (nano-TiO₂) to RAW264.7 cells. RAW264.7 cells were treated with 0 and 100 μg/ml nano-TiO₂ for 24 h (for miRNA analysis). The differentially expressed miRNAs were detected using Illumina HiSeq™ 2000 sequencing. Through the bio-informatics analysis, miR-350 was found to play an important role in multiple signaling pathways, including MAPK signaling pathway, NF-kappa B signaling pathway and Apoptosis. To characterize the miR-350 function, miR-350 mimic was transfected into RAW264.7 cells for 24 h. MTT and Flow Cytometry were performed to detect cell proliferation, apoptosis and cell cycle (repetition), respectively. QRT-PCR, Western Blot methods and Luciferase assays were applied to detect expression of putative target gene PIK3R3. The results showed that miRNA profiles were differentially dysregulated. The apoptosis rate of miR-350 mimic group was significantly higher than negative control group (p < .05). Cell proliferation and cell cycle had no significant differences between treatment and negative control group. Compared with negative control, the level of protein of PIK3R3 was significantly decreased (p < .05), and the expression of 3'UTR constructs of PIK3R3 was significantly decreased (p < .05) in miR-350 mimic group. The expression of miRNAs was changed after exposed to nano-TiO₂, and biological function and target gene results showed miR-350 may promote RAW264.7 cell apoptosis through the negative regulation of PIK3R3 gene. Our results could provide a basis for further understanding of toxicity and possible mechanisms of nano-TiO₂ exposure.

LncRNA-PAGBC acts as a microRNA sponge and promotes gallbladder tumorigenesis

Long noncoding RNAs (lncRNAs) play roles in the development and progression of many cancers; however, the contributions of lncRNAs to human gallbladder cancer (GBC) remain largely unknown. In this study, we identify a group of differentially expressed lncRNAs in human GBC tissues, including prognosis-associated gallbladder cancer lncRNA (lncRNA-PAGBC), which we find to be an independent prognostic marker in GBC Functional analysis indicates that lncRNA-PAGBC promotes tumour growth and metastasis of GBC cells. More importantly, as a competitive endogenous RNA (ceRNA), lncRNA-PAGBC competitively binds to the tumour suppressive microRNAs miR-133b and miR-511. This competitive role of lncRNA-PAGBC is required for its ability to promote tumour growth and metastasis and to activate the AKT/mTOR pathway. Moreover, lncRNA-PAGBC interacts with polyadenylate binding protein cytoplasmic 1 (PABPC1) and is stabilized by this interaction. This work provides novel insight on the molecular pathogenesis of GBC.

miR-511 promotes the proliferation of human hepatoma cells by targeting the 3'UTR of B cell translocation gene 1 (BTG1) mRNA

Aberrant expression of miR-511 is involved in the development of cancer, but the role of miR-511 in hepatocellular carcinoma (HCC) is not well documented. In this study, we explored the molecular mechanisms of miR-511 in hepatocarcinogenesis. Our results of bioinformatics analysis suggested that B cell translocation gene 1 (BTG1), a member of anti-proliferative gene family, was one of the putative targets of miR-511. The expression levels of miR-511 were significantly higher in 30 clinical HCC tissues than in corresponding peritumor tissues, and were negatively correlated with those of BTG1 in the HCC tissues (r=-0.6105, P<0.01). In human hepatoma cell lines HepG2 and H7402, overexpression of miR-511 dose-dependently inhibited the expression of BTG1, whereas knockdown of miR-511 dose-dependently increased the expression of BTG1. Luciferase reporter gene assays verified that miR-511 targeted the 3'UTR of BTG1 mRNA. In the hepatoma cells, overexpression of miR-511 significantly decreased BTG1-induced G₁ phase arrest, which was rescued by overexpression of BTG1. Furthermore, overexpression of miR-511 promoted the proliferation of the hepatoma cells, which was rescued by overexpression of BTG1. Conversely, knockdown of miR-511 inhibited cell proliferation, which was reversed by knockdown of BTG1. In conclusion, miR-511 promotes the proliferation of human hepatoma cells in vitro by targeting the 3'UTR of BTG1 mRNA.

Cancer cachexia-induced muscle atrophy: evidence for alterations in microRNAs important for muscle size

Muscle atrophy is a hallmark of cancer cachexia resulting in impaired function and quality of life and cachexia is the immediate cause of death for 20-40% of cancer patients. Multiple microRNAs (miRNAs) have been identified as being involved in muscle development and atrophy; however, less is known specifically on miRNAs in cancer cachexia. The purpose of this investigation was to examine the miRNA profile of skeletal muscle atrophy induced by cancer cachexia to uncover potential miRNAs involved with this catabolic condition. Phosphate-buffered saline (PBS) or Lewis lung carcinoma cells (LLC) were injected into C57BL/6J mice at 8 wk of age. LLC animals were allowed to develop tumors for 4 wk to induce cachexia. Tibialis anterior muscles were extracted and processed to isolate small RNAs, which were used for miRNA sequencing. Sequencing results were assembled with mature miRNAs, and functions of miRNAs were analyzed by Ingenuity Pathway Analysis. LLC animals developed tumors that contributed to significantly smaller tibialis anterior muscles (18.5%) and muscle cross-sectional area (40%) compared with PBS. We found 371 miRNAs to be present in the muscle above background levels. Of these, nine miRNAs were found to be differentially expressed. Significantly altered groups of miRNAs were categorized into primary functionalities including cancer, cell-to-cell signaling, and cellular development among others. Gene network analysis predicted specific alterations of factors contributing to muscle size including Akt, FOXO3, and others. These results create a foundation for future research into the sufficiency of targeting these genes to attenuate muscle loss in cancer cachexia.

Regulation of TRIM24 by miR-511 modulates cell proliferation in gastric cancer

Background

Increasing evidence highlights the important roles of tripartite motif containing 24 (TRIM24) in tumor initiation and malignant progression in many tumors, including gastric cancer (GC). Although TRIM24 expression is remarkably upregulated during GC carcinogenesis, the molecular mechanisms underlying TRIM24 dysregulation remain unexplored.

Methods

In this study, miRNA target prediction tools were applied to explore miRNAs that potentially target TRIM24. Western blot and quantitative reverse-transcriptase PCR (qRT-PCR) were performed to detected TRIM24 and miR-511 expression in GC tissues and cell lines. Dual-luciferase reporter assay was utilized to validate if TRIM24 is a direct target gene of miR-511. CCK-8 assay, cell colony formation assay, EdU incorporation assay and cell cycle analysis were performed to determine whether miR-511-mediated regulation of TRIM24 could affect GC progression.

Results

In our study, miR-511 was found to be downregulated in GC and an inverse correlation was observed between TRIM24 and miR-511 expression in primary GC tissues and cell lines. Dual-luciferase reporter assay further verified TRIM24 is a direct target of miR-511. Functional assays showed miR-511 overexpression inhibited cell growth, colony formation ability and cell cycle progression. Conversely, inhibition of endogenous miR-511 promoted these phenotypes in GC cells. Moreover, reintroduction of TRIM24 rescued miR-511-induced inhibitory effects on GC cells. Furthermore, miR-511 elicits tumor-suppressive effects through inactivating PI3K/AKT and Wnt/β-catenin pathways by suppressing TRIM24.

Conclusions

Our results provide the new evidence supporting the tumor-suppressive role of miR-511 in GC by suppressing TRIM24, suggesting that this novel miR-511/TRIM24 axis is critical in the control of gastric cancer tumorigenesis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13046-017-0489-1) contains supplementary material, which is available to authorized users.

Transcriptional profiling reveals protective mechanisms in brains of long-lived mice

The brain plays a central role in organismal aging but is itself most sensitive to aging-related functional impairments and pathologies. Insights into processes underlying brain aging are the basis to positively impact brain health. Using high-throughput RNA sequencing and quantitative polymerase chain reaction (PCR), we monitored cerebral gene expression in mice throughout their whole lifespan (2, 9, 15, 24, and 30 months). Differentially expressed genes were clustered in 6 characteristic temporal expression profiles, 3 of which revealed a distinct change between 24 and 30 months, the period when most mice die. Functional annotation of these genes indicated a participation in protection against cancer and oxidative stress. Specifically, the most enriched pathways for the differentially expressed genes with higher expression at 30 versus 24 months were found to be glutathione metabolism and chemokine signaling pathway, whereas those lower expressed were enriched in focal adhesion and pathways in cancer. We therefore conclude that brains of very old mice are protected from certain aspects of aging, in particular cancer, which might have an impact on organismal health and lifespan.

A Seven-microRNA Expression Signature Predicts Survival in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth common cancer. The differential expression of microRNAs (miRNAs) has been associated with the prognosis of various cancers. However, limited information is available regarding genome-wide miRNA expression profiles in HCC to generate a tumor-specific miRNA signature of prognostic values. In this study, the miRNA profiles in 327 HCC patients, including 327 tumor and 43 adjacent non-tumor tissues, from The Cancer Genome Atlas (TCGA) Liver hepatocellular carcinoma (LIHC) were analyzed. The associations of the differentially expressed miRNAs with patient survival and other clinical characteristics were examined with t-test and Cox proportional regression model. Finally, a tumor-specific miRNA signature was generated and examined with Kaplan-Meier survival, univariate\multivariate Cox regression analyses and KEGG pathway analysis. Results showed that a total of 207 miRNAs were found differentially expressed between tumor and adjacent non-tumor HCC tissues. 78 of them were also discriminatively expressed with gender, race, tumor grade and AJCC tumor stage. Seven miRNAs were significantly associated with survival (P value <0.001). Among the seven significant miRNAs, six (hsa-mir-326, hsa-mir-3677, hsa-mir-511-1, hsa-mir-511-2, hsa-mir-9-1, and hsa-mir-9-2) were negatively associated with overall survival (OS), while the remaining one (hsa-mir-30d) was positively correlated. A tumor-specific 7-miRNAs signature was generated and validated as an independent prognostic predictor. Collectively, we have identified and validated an independent prognostic model based on the expression of seven miRNAs, which can be used to assess patients' survival. Additional work is needed to translate our model into clinical practice.