Downregulation of microRNA-100/microRNA-125b is associated with lymph node metastasis in early colorectal cancer with submucosal invasion

Effect of the MiR-99b and MiR-135b on peritoneal carcinomatosis and liver metastasis in colorectal cancer

AIM

This study aimed to evaluate the expression levels of miR-99b and miR-135b in peritoneal carcinoma and liver metastases associated with Colorectal Cancer (CRC), assess their association with the intracellular signaling pathway proteins Kirsten Rat Sarcoma Virus (KRAS) and Akt, and investigate their effects on survival.

MATERIALS AND METHODS

Changes in the KRAS gene and Akt proteins, expression levels of miR-99b and miR-135b, and factors affecting survival were compared between colorectal cancer-associated peritoneal carcinomatosis and liver metastasis.

RESULTS

The expression levels of miR-99b and miR-135b and the immunohistochemical grade classification score of Akt were higher in colorectal cancer, peritoneal carcinomatosis, and liver metastasis than in normal tissues (p < 0.05). MiR-99b expression was highest in CRC, whereas miR-135b expression was highest in peritoneal carcinomatosis (p < 0.05). The expression level of miR-99b decreased and that of miR-135b increased in peritoneal and liver metastases compared with that in the tumor tissue. MiR-99b, Akt, and recurrence were risk factors that affected the overall survival rate in the model of clinical predictions (p = 0.045, p = 0.006, and p = 0.012, respectively).

CONCLUSION

While the expression of miR-99b was highest in the primary tumor, its decrease in liver metastasis and peritoneal carcinomatosis suggests that miR-99b has a protective effect against liver metastasis and peritoneal carcinomatosis. However, the detection of miR-135b expression was highest in peritoneal carcinomatosis and liver metastasis compared with that in the colorectal cancer tissues suggesting that it facilitates peritoneal carcinomatosis and liver metastasis. Furthermore, miR-99b, KRAS mutations, and Akt are risk factors for the overall survival of colorectal cancer.

miR-144-3p/miR-451a promotes lymphovascular invasion through repression of PTEN/p19 in rectal neuroendocrine tumors

BACKGROUND AND AIM

Although rectal neuroendocrine tumor (NET-G1) have potential metastatic capability, even among small tumors, no predictive biomarker for invasion and metastasis has been reported. We analyzed microRNA (miRNA) expression profiles in rectal NET-G1 tissues with and without lymphovascular invasion (LVI). Moreover, we then investigated their target genes to clarify the mechanism of invasion/metastasis in NET-G1.

METHODS

miRNA array analysis was performed using seven rectal NET-G1 tissues with LVI and seven without LVI. miRNA expression was confirmed by quantitative real-time PCR. A NET cell line H727 was transfected with miRNA mimic or target gene small interfering RNA, and migration and invasion assays were performed.

RESULTS

The expression levels of miR-144-3p and miR-451a were significantly higher in NET-G1 with LVI versus without LVI, as determined by miRNA array analysis and RT-qPCR. A significant correlation was observed between miR-144-3p and miR-451a expression levels, strongly suggesting miR144/451 cluster overexpression in NET-G1 with LVI. Bioinformatic analysis of target genes revealed that miR-144-3p and miR-451a directly interact with PTEN and p19 mRNA, respectively. Immunohistochemistry revealed significantly lower expression of PTEN and p19 in NET-G1 tissues with LVI than in those without LVI. The miR-144-3p and miR-451a mimic significantly increased cell migration/invasion capability, respectively. Knockdown of PTEN and p19 induced significant augmentation of cell invasion and migration capability, respectively.

CONCLUSIONS

Our data suggest that overexpression of miR-144/miR-451 cluster promotes LVI via repression of PTEN and p19 in rectal NET-G1 cells. miR-144/451 cluster may be a novel biomarker for predicting invasion/metastasis in rectal NET-G1.

Exosomal miRNAs as a Promising Source of Biomarkers in Colorectal Cancer Progression

Colorectal cancer (CRC) is the third most common type of cancer worldwide amongst males and females. CRC treatment is multidisciplinary, often including surgery, chemotherapy, and radiotherapy. Early diagnosis of CRC can lead to treatment initiation at an earlier stage. Blood biomarkers are currently used to detect CRC, but because of their low sensitivity and specificity, they are considered inadequate diagnostic tools and are used mainly for following up patients for recurrence. It is necessary to detect novel, noninvasive, specific, and sensitive biomarkers for the screening and diagnosis of CRC at earlier stages. The tumor microenvironment (TME) has an essential role in tumorigenesis; for example, extracellular vesicles (EVs) such as exosomes can play a crucial role in communication between cancer cells and different components of TME, thereby inducing tumor progression. The importance of miRNAs that are sorted into exosomes has recently attracted scientists’ attention. Some unique sequences of miRNAs are favorably packaged into exosomes, and it has been illustrated that particular miRNAs can be directed into exosomes by special mechanisms that occur inside the cells. This review illustrates and discusses the sorted and transported exosomal miRNAs in the CRC microenvironment and their impact on CRC progression as well as their potential use as biomarkers.

Role of extracellular LncRNA-SNHG14/miRNA-3940-5p/NAP12 mRNA in colorectal cancer

BACKGROUND

We aim to identify and analyze the expression of dyregulated RNAs in colorectal cancer (CRC).

METHODS

We selected a panel of RNAs specific to CRC composed of Nucleosome Assembly Protein 1 Like 2 (NAP1L2) mRNA, LNCRNA SNHG14 small nucleolar RNA host gene 14 (LNCRNA SNHG14) and homo sapiens microRNA-3940-5p(hsa-miRNA-3940-5p) from genetic and epigenetic databases. Validation of the chosen RNAs was achieved by real time quantitative PCR in sera of patients with CRC, versus controls groups (benign lesions and healthy individual).

RESULTS

We found that LLNCRNA SNHG14, hsa-miRNA-3940-5p and NAP1L2 mRNA had an excellent performance characteristics and more superior than CEA, and CA19.9 for differentiating CRC from controls. Combined expression of lncRNA SNHG14- hsa-miR-3940-5p and NAP1L2 mRNA had reached 100% sensitivity with accuracy 93%. Interestingly, serum hsa-miRNA-3940-5p could be an independent prognostic factor in CRC.

CONCLUSION

The extracellular lncRNA SNHG14- hsa-miR-3940-5p - NAP1L2 mRNA may aid in CRC management.KEY MESSAGESThe extracellular RNAs provide a potential class of noninvasive biomarkers with high specificity, accuracy and stability for detection of CRC.We used insilico data analysis followed by qPCR for detection of differential NAP1L2 gene expression with the selected epigenetic regulators.Our data presented interesting biomarker panel (NAP1L2 gene, lncRNA-SNHG14 and hsa-miR-3940-5p) that may be potential for CRC diagnosis and prognosis.

Siglec-15 Is an Immune Suppressor and Potential Target for Immunotherapy in the Pre-Metastatic Lymph Node of Colorectal Cancer

Lymph node metastasis indicates a poor prognosis in colorectal cancer. To better understand the underlying mechanisms of lymph node metastasis, we analyzed transcriptome characteristics of the pre-metastatic lymph node, a putative microenvironment favorable for the seeding and proliferation of cancer cells. Thus, we tried to compare and elucidate the transcriptional and immune characteristics of sentinel lymph nodes (SNs) with matched non-sentinel lymph nodes (NSNs) in colorectal cancer patients. In this study, a total of 38 pairs of SNs and NSNs were collected, in which 26 pairs of non-metastatic lymph nodes were subjected to RNA-seq and bioinformatics analysis for the gene expression profiles. There were 16 differentially expressed genes between SNs and NSNs being identified, including 9 upregulated and 7 downregulated genes in SN. Gene Ontology (GO) classification analysis revealed that the differentially expressed genes were mainly involved in leukocyte differentiation, chemokine secretion, and immune system regulation. In the meantime, gene set enrichment analysis (GSEA) showed that immune-related signaling pathways, such as transforming growth factor beta (TGF-β) signaling and tumor necrosis factor alpha (TNF-α)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, were enriched in NSN, while cell proliferation–related signaling pathways were enriched in SN, including MYC signaling and G2M checkpoint signaling. We further identified SIGLEC15 as a top upregulated gene in SN. However, RNAscope assay showed that SIGLEC15 was not largely co-expressed with M2 macrophage marker CD163. We then selected eight pairs of lymph nodes for further cytological studies. Flow cytometry analysis revealed that Siglec-15 was expressed on all myeloid cell subsets. The relative expression of SEGLEC15 (SN/NSN) was correlated with the microsatellite instability (MSI) status in colorectal cancer patients. Further studies found that small interfering ribonucleic acid (siRNA)-mediated silencing of SLGLEC15 can enhance the anti-tumor function of T cells, as indicated by cytokine release analysis. In conclusion, we presented here a first report on the gene expression profiling of the pre-metastatic lymph node in colorectal cancer. The findings in this study suggest that SIGLEC15 plays an important role in SN immunosuppression. SEGLEC15 silencing could be a therapeutic strategy for restoring T cell function in tumor SNs.

MiR-125b enhances autophagic flux to improve septic cardiomyopathy via targeting STAT3/HMGB1

We explore the role of miR-125b in septic cardiomyopathy, focusing on miR-125b/STAT3/HMGB1 axis. CLP mouse model and LPS-stimulated primary rat cardiomyocytes (CMs) and H9C2 cell were used as in vivo and in vitro models of septic cardiomyopathy, respectively. qRT-PCR and western blot were performed to measure expression levels of miR-125b, STAT3, HMGB1, and autophagy-related proteins. MTT assay was employed to examine LPS toxicity. Dual luciferase activity assay and CHIP were performed to validate interactions of miR-125b/STAT3 and STAT3/HMGB1 promoter. Immunostaining was used to assess the level of autophagic flux. ROS level was measured by fluorescence assay. Heart functions were examined via intracoronary Doppler ultrasound. miR-125b was diminished while STAT3 and HMGB1 were elevated in the heart tissue following CLP surgery and in LPS-treated H9C2 cells. LPS treatment up-regulated ROS generation and suppressed autophagic flux. Overexpression of miR-125b mimics or knockdown of STAT3 or HMGB1 alleviated LPS-induced hindrance of autophagic flux and ROS production. miR-125b directly targeted STAT3 mRNA and STAT3 bound with HMGB1 promoter. Overexpression of miR-125b mitigated myocardial dysfunction induced by CLP in vivo. Hyperactivation of STAT3/HMGB1 caused by reduced miR-125b contributes to ROS generation and the hindrance of autophagic flux during septic cardiomyopathy, leading to myocardial dysfunction.

Identification of Molecules Responsible for Therapeutic Effects of Extracellular Vesicles Produced from iPSC-Derived MSCs on Sjo¨gren's Syndrome

Recent research indicated that extracellular vesicles (EVs) derived from mesenchymal stem/stromal cells (MSCs) are a promising alternative to MSCs for immunomodulatory therapy. However, the contents of MSC-EVs would change as their parent MSCs change, hence the therapeutic efficacy of MSC-derived EVs (MSC-EVs) would largely depend on donors, tissue sources and culture conditions of MSCs. To overcome limitations of tissue-derived MSCs, we previously used MSCs derived from human induced pluripotent stem cells (iMSCs) to produce EVs and demonstrated their therapeutic potential in a mouse model of secondary Sjo¨gren's Syndrome. Here, we further found that EVs from early-passage iMSCs had better immunomodulatory potency than EVs from late-passage iMSCs in TLR4-stimulated splenocytes and in a mouse model of primary Sjögren's syndrome. Comparative molecular profiling using proteomics and microRNA sequencing revealed distinctive molecular profiles of iMSC-EVs with or without immunomodulation capacity. Amongst them, manipulation of TGF-β1, miR-21 and miR-125b levels in iMSC-EVs significantly affected their immunosuppressive effects. These findings would help improve our understanding of the molecular mechanism underlying iMSC-EV-mediated immunomodulation and further provide strategies to improve regulatory function of EVs for the treatment of immune-mediated diseases.

Bioinformatics analysis of dysregulated exosomal microRNAs derived from oral squamous cell carcinoma cells

PURPOSE

The present study aimed to identify dysregulated exosomal miRNAs associated with diagnostic and therapeutic biomarkers in oral squamous cell carcinoma (OSCC).

METHODS

Microarray analysis was used to compare expression profiles of exosomal miRNAs in the OSCC-derived cell lines HSC-2, HSC-3, Ca9-22, and HO-1-N1 with those in human normal keratinocytes (HNOKs). The identified OSCC-related miRNAs and their potential target genes were analyzed with bioinformatic analyses, and the data were subjected to Ingenuity Pathway Analysis (IPA) to clarify functional networks and gene ontologies of the identified exosomal miRNAs secreted by OSCC cells.

RESULTS

Comparison with HNOKs detected 8 upregulated and 12 downregulated miRNAs in OSCC-secreted exosomes. The potential target mRNAs of these dysregulated miRNAs were suggested by IPA, and 6 significant genetic networks were indicated by genetic network analysis. Furthermore, 4 crucial upstream miRNAs-miR-125b-5p, miR-17-5p, miR-200b-3p, and miR-23a-3p-were identified. miR-125b-5p was a central node in the most significant network. Gene ontology analysis showed significant enrichment of genes with cancer-related functions, such as molecular mechanisms of cancer, cell cycle, and regulation of the epithelial-mesenchymal transition.

CONCLUSION

These results provide a comprehensive view of the functions of dysregulated exosomal miRNAs in OSCC, thus illuminating OSCC tumorigenesis and development.

Essential functions of miR-125b in cancer

MicroRNAs (miRNAs) are small and highly conserved non-coding RNAs that silence target mRNAs, and compelling evidence suggests that they play an essential role in the pathogenesis of human diseases, especially cancer. miR-125b, which is the mammalian orthologue of the first discovered miRNA lin-4 in Caenorhabditis elegans, is one of the most important miRNAs that regulate various physiological and pathological processes. The role of miR-125b in many types of cancer has been well established, and so here we review the current knowledge of how miR-125b is deregulated in different types of cancer; its oncogenic and/or tumour-suppressive roles in tumourigenesis and cancer progression; and its regulation with regard to treatment response, all of which are underlined in multiple studies. The emerging information that elucidates the essential functions of miR-125b might help support its potentiality as a diagnostic and prognostic biomarker as well as an effective therapeutic tool against cancer.

MicroRNA-99 family in cancer and immunity

The microRNA (miR)-99 family comprising miR-99a, miR-99b, and miR-100 is an evolutionarily conserved family with existence dating prior to the bilaterians. Members are typically oncogenic in leukemia while their functional roles in other cancers alternate between that of a tumor suppressor and a tumor promoter. Targets of the miR-99 family rank in the lists of oncogenes and tumor suppressors, thereby illustrating the dual role of this miR family as oncogenic miRs (oncomiRs) and tumor suppressing miRs (TSmiRs) in different cellular contexts. In addition to their functional roles in cancers, miR-99 family is implicated in the modulation of macrophage inflammatory responses and T-cell subsets biology, thereby exerting critical roles in the maintenance of tissue homeostasis, establishment of peripheral tolerance as well as resolution of an inflammatory reaction. Here, we review emerging knowledge of this miR family and discuss remaining concerns linked to their activities. A better dissection of the functional roles of miR-99 family members in cancer and immunity will help in the development of novel miR-99-based therapeutics for the treatment of human cancer and immune-related diseases. This article is categorized under: RNA in Disease and Development > RNA in Disease.

A promising naphthoquinone [8-hydroxy-2-(2-thienylcarbonyl)naphtho[2,3-b]thiophene-4,9-dione] exerts anti-colorectal cancer activity through ferroptosis and inhibition of MAPK signaling pathway based on RNA sequencing

Naphthoquinones are naturally occurring metabolites with recognized anti-cancer potential but limited clinical application. This study investigated the molecular mechanism of 8-hydroxy-2-(2-thenoyl)naphtho[2,3-b]thiophene-4,9-dione (1), a new candidate for colorectal cancer (CRC) treatment, using different experimental settings: MTT, clonogenic, wound healing, and cell cycle assays; as well as RNA sequencing. Naphthoquinone 1 selectively reduced the viability and migration of HT-29 cells by G2/M arrest and changes in their transcriptome signature with significant effect on cellular survival, proliferation, angiogenesis, response to interferon, oxidative stress, and immune response. Impact analysis identified ferroptosis and MAPK pathways as significantly affected. In summary, our results suggest that 1 induces the selective death of CRC cells by inducing oxidative stress, ferroptosis, and MAPK inhibition.

Exosomal miR-200c-3p negatively regulates the migraion and invasion of lipopolysaccharide (LPS)-stimulated colorectal cancer (CRC)

Background

Colorectal cancer (CRC) is a leading cancer and a major cause of death. Lipopolysaccharide (LPS), an abundant component in gut microbiome, is involved in CRC progression and metastasis, potentially through regulating the miRNA composition of CRC-derived exosomes. In this study, we aimed to identify miRNA species in exosome which regulates CRC progression after LPS stimulation.

Results

Firstly, we discovered a shift of miRNA profile in CRC exosome after LPS stimulation. Among the differentially expressed miRNAs, we identified miR-200c-3p as a potential key regulator of CRC progression and metastasis. Retrospective analysis revealed that miR-200c-3p was elevated in CRC tumor tissues, but decreased in the serum exosome in CRC patients. In vitro experiments demonstrated that exosomal miR-200c-3p expression did not influence CRC cell proliferation, but negatively regulated their capacity of migration and invasion in the presence of LPS. miR-200c-3p level in exosome influenced exosomal expression of Zinc finger E-box-binding homeobox-1 (ZEB-1) mRNA, one of the miR-200c targets which affects migration and invasion capacity, and further altered ZEB-1 protein expression in CRC cell. In addition, exosomal miR-200c-3p promotes apoptosis of HCT-116 cells.

Conclusions

Our findings indicate that exosomal miR-200c-3p inhibits CRC migration and invasion, and promotes their apoptosis after LPS stimulation. It is suggested as a potential diagnostic marker and therapeutic target of CRC.

The Emerging Roles of miR-125b in Cancers

MicroRNAs (miRNAs) are endogenous, noncoding, single-stranded RNA molecules of 22 nucleotides in length. MiRNAs have both tumor-suppressive properties and oncogenic properties that can control critical processes in tumors. Mature miR-125b originates from miR-125b-1 and miR-125b-2 and leads to the degradation of target mRNAs or the inhibition of translation through binding to the 3′ untranslated regions (3′-UTR) of target mRNAs. Importantly, miR-125b is involved in regulating NF-κB, p53, PI3K/Akt/mTOR, ErbB2, Wnt, and another signaling pathways, thereby controlling cell proliferation, differentiation, metabolism, apoptosis, drug resistance and tumor immunity. This review aims to summarize the recent literature on the role of miR-125b in the regulation of tumorigenesis and to explore its potential clinical application in the diagnosis, prognosis and clinical treatment of tumors.

The circular RNA hsa-circ-0072309 plays anti-tumour roles by sponging miR-100 through the deactivation of PI3K/AKT and mTOR pathways in the renal carcinoma cell lines

Aims: To explore the roles and regulatory mechanisms of the circular RNA (circRNA)-hsa-circ-0072309 in CAKI-1 and ACHN cells. Methods: CAKI-1 and ACHN cells were transfected with hsa-circ-0072309 overproduction vector (circRNA) and microRNA-100 (miR-100) mimic or the corresponding controls. Cell viability was detected with the CCK-8. The protein expression levels of p53, c-Myc, cleaved-caspase-3/9, matrix metalloproteinase (MMP)-2/9, vimentin, AKT, PI3K and mTOR were individually determined through western blot. qRT-PCR was used to examine the expressions of hsa-circ-0072309 and miR-100. The apoptotic rate and the migration or invasion rates were separately determined by the annexin v-FITC/PI with a flow cytometer and modified two-chamber migration assay or millicell hanging cell culture. Results: The hsa-circ-0072309 was poorly expressed in tumor tissue. Abundant hsa-circ-0072309 induced the inhibitions of cell proliferation, migration and invasion, as well as the PI3K/AKT and the mTOR cascades but enhancement of apoptosis. circRNA stimulated the down-regulation of miR-100, which was low-expressed in tumour tissue and whose overproduction abolished the impacts of circRNA on these elements mentioned above. Conclusion: The hsa-circ-0072309 played anti-tumour roles by targeting miR-100 by blocking the PI3K/AKT and mTOR cascades in the CAKI-1 and ACHN cell lines.

Long noncoding RNA HAGLROS promotes the process of mantle cell lymphoma by regulating miR-100/ATG5 axis and involving in PI3K/AKT/mTOR signal

This research planned to grab the expression and impact of lncRNA HAGLROS in the biology and progression of mantle cell lymphoma. HAGLROS level in mantle cell lymphoma cell lines was detected, followed by investigation of the influences of HAGLROS silencing on Mino cell biological performances. Afterwards, the express patterns of HAGLROS vs. miR-100, as well as miR-100 vs. ATG5, were investigated. Furthermore, whether HAGLROS could regulate the signals of PI3K/AKT/mTOR was analyzed. HAGLROS level was high in mantle cell lymphoma cell lines. Silencing of HAGLROS inhibited Mino cell viability, increased apoptosis and decreased autophagy by sponging miR-100. Moreover, miR-100 targeted ATG5 fixed. Furthermore, HAGLROS suppression resulted in inhibition on the briskness of PI3K/AKT/mTOR signals. Concurrently HAGLROS suppression and miR-100 inhibitor markedly changed the impacts of HAGLROS down-regulation alone on activating PI3K/AKT/mTOR signals, which could further change after co-transfection of si-HAGLROS + miR-100 inhibitor + siATG5. Our findings point out that expression of HAGLROS is increased in mantle cell lymphoma cells and may function as an oncogene in mantle cell lymphoma. HAGLROS may promote tumour development by regulating miR-100/ATG5/PI3K/AKT/mTOR axis.

Modified TLR-mediated downregulation of miR-125b-5p enhances CD248 (endosialin)-induced metastasis and drug resistance in colorectal cancer cells

CD248, also called endosialin or tumor endothelial marker-1, is markedly upregulated in almost all cancers, including colon cancers. Changes in microRNA profiles are one of the direct causes of cancer development and progression. In this study, we investigated whether a change in CD248 expression in colon cancer cells could induce drug resistance after chemotherapy, and we explored the relationship between miR-125b-5p levels and CD248 expression in Toll-like receptor (TLR)-modified chemoresistant colon cancer cells. TLR2/6 and TLR5 upregulation in drug-resistant colon cancer cells contributed to miR-125b-5p downregulation and specificity protein 1 (Sp1)-mediated CD248 upregulation via nuclear factor-kappa B (NF-κB) activation. Exposure to specific TLR2/6 or TLR5 ligands enhanced the expression of mesenchymal markers as well as the migratory activity of oxaliplatin- or 5-fluorouracil-resistant colon cancer cells. The transfection of a synthetic miR-125b-5p mimic into chemoresistant cells prevented Sp1 and CD248 activation and significantly impaired invasive activity. Furthermore, Sp1 or CD248 gene silencing as well as miR-125b-5p overexpression markedly reversed drug resistance and inhibited epithelial-mesenchymal transition in colon cancer cells. Taken together, these results suggest that changes in miR-125b-5p levels play an important role in Sp1-mediated CD248 expression and the development of drug resistance in TLR-mutated colon cancer cells.

MiR-218 and miR-100 polymorphisms as markers of irinotecan-based chemotherapy response in metastatic colorectal cancer

PURPOSE

Colorectal cancer is the fourth cause of cancer-related death. Drug toxicity and resistance remain concerns of major importance. miR-100 and miR-218 are micro-RNAs that regulate cellular proliferation, differentiation and apoptosis acting as oncogenes and tumour suppressors; their functions and have been linked with toxicity development and drug resistance.

METHODS

We investigated the correlation between rs11134527 miR-218 and rs1834306 miR-100 polymorphisms and irinotecan-based regimens with regard to drug efficacy and toxicity. A total of 105 mCRC patients receiving irinotecan-based regimens were included in our study and assessed in terms of toxicity development and response to treatment. Rs11134527 miR-218 and rs1834306 miR-100 polymorphism genotyping in the peripheral blood was performed with PCR-RFLP.

RESULTS

Neither rs11134527 miR-218 nor rs1834306 miR-100 are associated with toxicity risk to treatment regimens. GA/AA genotypes of rs11134527 and CT/TT genotypes of rs1834306 were associated with a significantly reduced time-to-progression (TTP) and overall survival (OS).

CONCLUSIONS

GA/AA genotypes of rs11134527 miR-218 and CT/TT genotypes of rs1834306 miR-100 polymorphisms could serve as prognostic biomarkers of TTP and OS. Carriers of the A allele of the miR-218 rs11134527 and T allele of the miR-100 rs1834306 polymorphisms are more likely not to respond to irinotecan-based therapies. However, further studies in larger patient populations are required.

Serum microRNA-381: A Potential Marker for Early Diagnosis of Gastric Cancer

PURPOSE

The purpose of this study was to explore the potential early diagnostic value of serum microRNA-381(miRNA-381) in patients with gastric cancer (GC).

MATERIALS AND METHODS

Patients with advanced gastric cancer (AGC) and early gastric cancer (EGC), as well as healthy individuals, were enrolled in this study. Expression of miRNA-381 in serum was detected using real-time quantitative PCR. Electrochemiluminescence analysis was used to investigate the expression of classic tumor markers, including carbohydrate antigen (CA) 199, CA724, and carcinoembryonic antigen. Finally, receiver operating characteristic curve and Kaplan-Meier analysis were used to determine the value of miRNA-381 in clinical diagnosis of GC.

RESULTS

miRNA-381 was differentially expressed among the study groups. AUC analysis showed that the sensitivity and specificity of serum miRNA-381 in the diagnosis of GC were superior to those of other tumor markers. Furthermore, low levels of miRNA-381 expression were positively correlated with lymph node metastasis and AGC. Finally, Kaplan-Meier survival analysis showed that down-regulation of miRNA-381 was associated with lymph node metastasis and the development of GC.

CONCLUSION

miRNA381, which was down-regulated in GC, might be a novel early diagnosis marker for patients with GC.

LSGSP: a novel miRNA–disease association prediction model using a Laplacian score of the graphs and space projection federated method

Lots of research findings have indicated that miRNAs (microRNAs) are involved in many important biological processes; their mutations and disorders are closely related to diseases, therefore, determining the associations between human diseases and miRNAs is key to understand pathogenic mechanisms. Existing biological experimental methods for identifying miRNA–disease associations are usually expensive and time consuming. Therefore, the development of efficient and reliable computational methods for identifying disease-related miRNAs has become an important topic in the field of biological research in recent years. In this study, we developed a novel miRNA–disease association prediction model using a Laplacian score of the graphs and space projection federated method (LSGSP). This integrates experimentally validated miRNA–disease associations, disease semantic similarity scores, miRNA functional scores, and miRNA family information to build a new disease similarity network and miRNA similarity network, and then obtains the global similarities of these networks through calculating the Laplacian score of the graphs, based on which the miRNA–disease weighted network can be constructed through combination with the miRNA–disease Boolean network. Finally, the miRNA–disease score was obtained via projecting the miRNA space and disease space onto the miRNA–disease weighted network. Compared with several other state-of-the-art methods, using leave-one-out cross validation (LOOCV) to evaluate the accuracy of LSGSP with respect to a benchmark dataset, prediction dataset and compare dataset, LSGSP showed excellent predictive performance with high AUC values of 0.9221, 0.9745 and 0.9194, respectively. In addition, for prostate neoplasms and lung neoplasms, the consistencies between the top 50 predicted miRNAs (obtained from LSGSP) and the results (confirmed from the updated HMDD, miR2Disease, and dbDEMC databases) reached 96% and 100%, respectively. Similarly, for isolated diseases (diseases not associated with any miRNAs), the consistencies between the top 50 predicted miRNAs (obtained from LSGSP) and the results (confirmed from the above-mentioned three databases) reached 98% and 100%, respectively. These results further indicate that LSGSP can effectively predict potential associations between miRNAs and diseases.

Lots of research findings have indicated that the mutations and disorders of miRNAs (microRNAs) are closely related to diseases. Therefore, determining the associations between human diseases and miRNAs is key to understand the pathogenic mechanisms.

A two-microRNA-based signature predicts first-line chemotherapy outcomes in advanced colorectal cancer patients

Prognostic and predictive markers are needed to predict the clinical outcomes of patients with advanced colorectal cancer (CRC) who receive standard first-line treatments. We performed a prospective cohort study in advanced CRC patients to identify a miRNA signature that could predict the benefit of receiving first-line chemotherapy for these patients. Twenty-one paired tumours and adjacent normal tissues were collected from advanced CRC patients and analysed by miRNA microarrays. Between tumour and normal tissues, 33 miRNAs were differentially expressed and was confirmed by qRT-PCR from another group of 67 patients from a prospective cohort study. A two-miRNA-based signature was obtained using the LASSO Cox regression model based on the association between the expression of each miRNA and the PFS of individual patients. Internal and external validation cohorts, including 40 and 44 patients with advanced CRC, respectively, were performed to prove the prognostic and predictive value of this signature. A signature was built based on two miRNAs, miR-125b-2-3p and miR-933. CRC patients were classified into low- and high-risk groups for disease progression based on this tool. The patients with low risk scores generally had better PFS than those with high risk scores. In the training set, the median PFS in the low- and high-risk groups were 12.00 and 7.40 months, respectively. In the internal validation set, the median PFS in the low- and high-risk groups were 9.90 and 5.10 months, respectively. In the external validation set, the median PFS in the low- and high-risk groups were 9.90 and 6.40 months, respectively. Furthermore, we detected miR-125b-2-3p associated with CRC cell sensitivity to first-line chemotherapy. Our two-miRNA-based signature was a reliable prognostic and predictive tool for tumour progression in patients with advanced CRC, and might be able to predict the benefit of receiving standard first-line chemotherapy in CRC.

Long noncoding RNA HAGLROS regulates apoptosis and autophagy in colorectal cancer cells via sponging miR-100 to target ATG5 expression

The aim of this study was to explore the relationship between the expression of HOXD antisense growth-associated long noncoding RNA (HAGLROS) and prognosis of patients with colorectal cancer (CRC), as well as the roles and regulatory mechanism of HAGLROS in CRC development. The HAGLROS expression in CRC tissues and cells was detected. The correlation between HAGLROS expression and survival time of CRC patients was investigated. Moreover, HAGLROS was overexpressed and suppressed in HCT-116 cells, followed by detection of cell viability, apoptosis, and the expression of apoptosis-related proteins and autophagy markers. Furthermore, the association between HAGLROS and miR-100 and the potential targets of miR-100 were investigated. Besides, the regulatory relationship between HAGLROS and PI3K/AKT/mTOR pathway was elucidated. The results showed that HAGLROS was highly expressed in CRC tissues and cells. Highly expression of HAGLROS correlated with a shorter survival time of CRC patients. Moreover, knockdown of HAGLROS in HCT-116 cells induced apoptosis by increasing the expression of Bax/Bcl-2 ratio, cleaved-caspase-3, and cleaved-caspase-9, and inhibited autophagy by decreasing the expression of LC3II/LC3I and Beclin-1 and increasing P62 expression. Furthermore, HAGLROS negatively regulated the expression of miR-100, and HAGLROS controlled HCT-116 cell apoptosis and autophagy through negatively regulation of miR-100. Autophagy related 5 (ATG5) was verified as a functional target of miR-100 and miR-100 regulated HCT-116 cell apoptosis and autophagy through targeting ATG5. Besides, HAGLROS overexpression activated phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway. In conclusion, a highly expression of HAGLROS correlated with shorter survival time of CRC patients. Downregulation of HAGLROS may induce apoptosis and inhibit autophagy in CRC cells by regulation of miR-100/ATG5 axis and PI3K/AKT/mTOR pathway.

Circulating microRNA-99 family as liquid biopsy marker in pancreatic adenocarcinoma

PURPOSE

Recently, we identified the microRNA-99 family as unfavorable prognostic factor in patients with pancreatic ductal adenocarcinoma (PDAC). The aim of this study is to evaluate its value as circulating biomarker for PDAC.

METHODS

Tissue and corresponding preoperative blood samples of 181 patients with PDAC UICC Stages I-IV (n = 90), intraductal papillary mucinous neoplasm (IPMN, n = 11), chronic pancreatitis (n = 40), pancreatic cystadenoma (n = 20), and age-matched healthy blood serum controls (n = 20) were collected between 2014 and 2017 prospectively. Expression of microRNA-21 as confirmatory marker and the microRNA-99 family, consisting of microRNA-99a, -99b, and -100, was analyzed by qRT-PCR. Target analysis of insulin-like growth factor 1 receptor (IGF1R) was performed using tissue array immunohistochemistry and Western blotting.

RESULTS

Expression of microRNA-99 family members was significantly increased in macrodissected tumor tissue and corresponding blood serum samples (p < 0.05) of patients with PDAC of all stages. Correspondingly, its target protein IGF1R was upregulated (p < 0.001) in carcinoma tissue. Circulating and tissue-related microRNA-100 could well discriminate PDAC from healthy samples with area under the receiver operating characteristic (ROC) curve (AUC) values of 0.81 and 0.85, respectively. Low expression of circulating microRNA-100 was associated with significantly improved overall survival (p = 0.004) and recurrence-free survival (p = 0.03) in multivariate analyses. Circulating microRNA-21 was overexpressed in PDAC with fair discrimination between PDAC and healthy controls (AUC = 0.71) and decreased overall survival (p = 0.046) and recurrence-free survival (p = 0.03) in PDAC patients.

CONCLUSIONS

Multivariate survival and ROC analyses identified circulating microRNA-100 as potential diagnostic and prognostic marker in PDAC patients.

MicroRNA analysis of gastroenteropancreatic neuroendocrine tumors and metastases

The incidence of neuroendocrine neoplasias (NEN) continues to increase. Since the primary tumor cannot be diagnosed in some cases of metastatic disease, new biomarkers are clearly needed to find the most probable site of origin. Tissue samples from 79 patients were analyzed and microRNA profiles were generated from a total of 76 primary tumors, 31 lymph node and 14 solid organ metastases. NEN metastases were associated with elevated levels of miR-30a-5p, miR-210, miR-339-3p, miR-345 and miR-660. Three microRNAs showed a strong correlation between proliferation index and metastatic disease in general (miR-150, miR-21 and miR-660). Further, each anatomic location (primary or metastatic) had one or more site-specific microRNAs more highly expressed in these tissues. Comparison between primary tumors and metastases revealed an overlap only in pancreatic (miR-127) and ileal tumors (let-7g, miR-200a and miR-331). This thorough analysis of gastroenteropancreatic neuroendocrine tumors demonstrates site-specific microRNA profiles, correlation with proliferation indices as well as corresponding nodal and distant metastases. Using microRNA profiling might improve NEN diagnostics by linking metastases to a most probable site of origin.

High miR-100 expression is associated with aggressive features and modulates TORC1 complex activation in lung carcinoids

PURPOSE

Mammalian target of rapamycin (mTOR) is a promising therapeutic target in advanced lung carcinoid patients. However, the mechanisms of mTOR modulation and of responsiveness to mTOR inhibitors are largely unclear. Our aim was to analyze the expression and functional role of specific miRNAs in lung carcinoids as an alternative mechanism targeting mTOR pathway.

EXPERIMENTAL DESIGN

Seven miRNAs, selected by bioinformatic tools and literature search, were analyzed in 142 lung neuroendocrine neoplasms (92 carcinoids and a control group of 50 high grade neuroendocrine carcinomas), and compared with mTOR mRNA expression and clinical/pathological parameters. Tissue results were validated in vitro in two lung carcinoid cell lines by specific RNA interference and biological/pharmacological tests.

RESULTS

Tissutal expression of five miRNAs (miR-99b, miR-100, miR-155, miR-193a-3p, miR-193a-5p) was inversely correlated with mTOR mRNA expression, supporting their role in the negative regulation of mTOR transcription. High expression of miR-100, miR-193a-3p and miR-193a-5p was associated with aggressive features and, for the former two, with shorter time to progression. In H727 and UMC11 lung carcinoid cells, miR-100 modulated mTOR RNA and TORC1 complex protein expression, positively promoted cell migration and negatively influenced cell proliferation. Moreover, miR-100 directly influenced responsiveness of H727 and UMC11 cells to rapamycin.

CONCLUSIONS

MiR-100 actively participates to the regulation of mTOR expression in lung carcinoids and represents a novel candidate prognostic biomarker for this tumor type; moreover, inhibition of its expression is associated to increased responsiveness to mTOR inhibitors and might represent a novel strategy to sensitize lung carcinoids to these target agents.

MicroRNA-125b inhibits cell proliferation and induces cell apoptosis in esophageal squamous cell carcinoma by targeting BMF

MicroRNAs (miRNAs) have been reported to regulate the expression of genes by suppressing translation or facilitating mRNA decay. Their expression regulates a wide variety of cellular processes, including the development and progression of cancer. Esophageal squamous cell carcinoma (ESCC) is a malignant cancer with high morbidity and recurrence in Asia. In the present study, the biological function of miR-125b and its underlying mechanism in ESCC were explored. The results revealed that miR-125b expression was significantly decreased in ESCC tissues and cell lines. A decrease in miR-125b was markedly related to lymphatic metastasis in patients. Functional analysis revealed that the overexpression of miR-125b using miR-125b mimics significantly inhibited cell growth and induced cell apoptosis, and increased the G1 phase of the cell cycle in EC109 and EC9706 cells. Notably, the miR-125b inhibitors revealed the opposite effect. Additionally, overexpression of miR-125b significantly inhibited tumor growth in vivo. Furthermore, BCL-2-modifying factor (BMF) was considered to be a potential candidate target of miR-125b based on miRNA target databases. miR-125b negatively regulated BMF expression by directly binding to its 3′-untranslated region. BMF was a functional target of miR-125b in the regulation of cell proliferation, cell apoptosis and the cell cycle in EC109 and EC9706 cells. In clinical ESCC specimens, BMF expression was upregulated, and negatively correlated with that of miR-125b. In conclusion, miR-125b had an antitumor role in ESCC cells mediated by targeting BMF, which can be potentially useful for tumorigenesis in ESCC.

Inhibition of microRNA-21-3p suppresses proliferation as well as invasion and induces apoptosis by targeting RNA-binding protein with multiple splicing through Smad4/extra cellular signal-regulated protein kinase signalling pathway in human colorectal cancer HCT116 cells

MicroRNA-21-3p (miR-21-3p), the passenger strand of pre-mir-21, has been found to be high-expressing in various cancers and to be associated with tumour malignancy, which is proposed as a novel focus in malignant tumours. Colorectal cancer (CRC), currently known as one of the most prevalent malignancy, is a leading cause of cancer death. This study aimed to investigate the key role of miR-21-3p in CRC by inhibiting its expression using transfection with miR-21-3p inhibitors into human CRC HCT116 cells. Results showed that the expression of miR-21-3p was higher than other CRC cells used in the study including Lovo, HT29, Colo320 and SW480 cells, inhibition of which suppressed the proliferation and induced cell cycle arrest in HCT116 cells. Besides, transfection with miR-21-3p inhibitors also attenuated cell migration and invasion, and induced apoptosis as well. Moreover, luciferase assay confirmed RBPMS as a direct target of miR-21-3p in HCT116 cells. Further, miR-21-3p inhibitors increased the nuclear accumulation of Smad4 and reduced phosphorylation of ERK. Interestingly, we found that silence of RBPMS using RNA interference (siRNA) not only elevated the cell viability but also increased the phosphorylation of ERK and reversed the nuclear accumulation of Smad4 induced by miR-21-3p inhibitors in HCT116 cells. Data suggest that inhibition of miR-21-3p suppresses cell proliferation, invasion as well as migration and induces apoptosis by directly targeting RBPMS through Smad4/ERK signalling pathway in HCT116 cells. Our study demonstrates miR-21-3p as a potent target for suppressing tumour progression of CRC which may have implications in CRC therapy in the future.

mTOR signaling-related MicroRNAs and Cancer involvement

MicroRNAs (miRNAs) are a class of single-stranded RNAs, 18-23 nucleotides in length that regulate gene expression at the post-transcriptional level. Dysregulation of miRNAs has been closely associated with the development of cancer. In the process of tumorigenesis, mammalian target of rapamycin (mTOR) plays important roles, and the mTOR signaling pathway is aberrant in various types of human cancers, including non-small cell lung cancer (NSCLC), breast cancer, prostate cancer, as well as others. However, the relationship between miRNAs and the mTOR signaling pathway is indistinct. Herein, we not only summarize the progress of miRNAs and the mTOR signaling pathway in cancers, but also highlight their role in the diagnosis and treatment in the clinic.

Combined low miRNA-29s is an independent risk factor in predicting prognosis of patients with hepatocellular carcinoma after hepatectomy: A Chinese population-based study

The prediction of prognosis of hepatocellular carcinoma (HCC) following partial hepatectomy is still an unresolved issue. The aim of this study is to identify the association between miRNA-29s family and the prognosis of patients with HCC in a large Asian cohort. We retrospectively reviewed 122 patients with HCC managed in our institution between 2008 and 2015. The expression of miRNA-29s was detected by real-time polymerase chain reaction (PCR). Prognostic factors were evaluated using Kaplan-Meier curves and Cox proportional hazards models. For the entire cohort of 122 patients, the normalized real-time PCR results showed that miRNA-29s (miR-29a, miR-29b, and miR-29c) were deregulated in tumor tissues as compared with corresponding nontumorous tissue samples. We then performed survival analysis to investigate the prognostic value of miRNA-29s. We found that low miR-29b was associated with a decreasing 5-year overall survival (OS) rate from 70.2% to 39.1% and low miR-29c was associated with a decreasing 5-year OS rate from 53.6% to 23.7%. We further conducted multivariate Cox proportional hazards analysis adding the variable of combined low miR-29b and low miR-29c. The results demonstrated that combined low miR-29b and miR-29c was an independent prognostic factor of patients with HCC. In conclusion, we found that the miRNA-29s were down-regulated in tumor tissues as compared with corresponding nontumorous tissue samples. Combined low miR-29b and miR-29c was an independent prognostic factor of patients with HCC.

miR-125b-5p functions as a tumor suppressor gene partially by regulating HMGA2 in esophageal squamous cell carcinoma

MicroRNAs (miRNAs) play important roles in the progression of human cancer including esophageal squamous cell carcinoma (ESCC). Although previous reports showed that miR-125b-5p was down-regulated in ESCC, the roles and mechanisms of loss of function of miR-125b-5p in ESCC were still unknown. Using microRNA microarray and GEO datasets, we found and confirmed that miR-125b-5p was down-regulated in ESCC tissues. In-vitro assays showed that ectopic miR-125b-5p expression repressed cell proliferation, migration and invasion, and induced cell senescence. We also found that miR-125b-5p reduced the expressions of cell cycle regulatory genes including CCNA2, CCND1 and CCNE1, and regulated the markers of epithelial to mesenchymal transition (EMT) including E-cadherin, N-cadherin and EMT associated transcription factor Slug, and also decreased the MMPs including MMP2, MMP7 and MMP13. Furthermore, the candidate target gene HMGA2 was negatively regulated by miR-125b-5p both in mRNA and protein levels. Importantly, knockdown of HMGA2 partially phenocopied the effects of miR-125b-5p overexpression on cell cycle regulators and EMT markers. In conclusion, our results suggested that overexpression of miR-125b-5p inhibited cell proliferation, migration and invasion partially by down-regulating HMGA2 in ESCC.

A biosystems approach to identify the molecular signaling mechanisms of TMEM30A during tumor migration

Understanding the molecular mechanisms underlying cell migration, which plays an important role in tumor growth and progression, is critical for the development of novel tumor therapeutics. Overexpression of transmembrane protein 30A (TMEM30A) has been shown to initiate tumor cell migration, however, the molecular mechanisms through which this takes place have not yet been reported. Thus, we propose the integration of computational and experimental approaches by first predicting potential signaling networks regulated by TMEM30A using a) computational biology methods, b) our previous mass spectrometry results of the TMEM30A complex in mouse tissue, and c) a number of migration-related genes manually collected from the literature, and subsequently performing molecular biology experiments including the in vitro scratch assay and real-time quantitative polymerase chain reaction (qPCR) to validate the reliability of the predicted network. The results verify that the genes identified in the computational signaling network are indeed regulated by TMEM30A during cell migration, indicating the effectiveness of our proposed method and shedding light on the regulatory mechanisms underlying tumor migration, which facilitates the understanding of the molecular basis of tumor invasion.

Downregulation of microRNA-100/microRNA-125b is associated with lymph node metastasis in early colorectal cancer with submucosal invasion

A majority of early colorectal cancers (CRCs) with submucosal invasion undergo surgical operation, despite a very low incidence of lymph node metastasis. Our study aimed to identify microRNAs (miRNAs) specifically responsible for lymph node metastasis in submucosal CRCs. MicroRNA microarray analysis revealed that miR‐100 and miR‐125b expression levels were significantly lower in CRC tissues with lymph node metastases than in those without metastases. These results were validated by quantitative real‐time PCR in a larger set of clinical samples. The transfection of a miR‐100 or miR‐125b inhibitor into colon cancer HCT116 cells significantly increased cell invasion, migration, and MMP activity. Conversely, overexpression of miR‐100 or miR‐125b mimics significantly attenuated all these activities but did not affect cell growth. To identify target mRNAs, we undertook a gene expression array analysis of miR‐100‐silenced HCT116 cells as well as negative control cells. The Ingenuity Pathway Analysis, TargetScan software analyses, and subsequent verification of mRNA expression by real‐time PCR identified mammalian target of rapamycin (mTOR) and insulin‐like growth factor 1 receptor (IGF1R) as direct, and Fas and X‐linked inhibitor‐of‐apoptosis protein (XIAP) as indirect candidate targets for miR‐100 involved in lymph node metastasis. Knockdown of each gene by siRNA significantly reduced the invasiveness of HCT116 cells. These data clearly show that downregulation of miR‐100 and miR‐125b is closely associated with lymph node metastasis in submucosal CRC through enhancement of invasion, motility, and MMP activity. In particular, miR‐100 may promote metastasis by upregulating mTOR, IGF1R, Fas, and XIAP as targets. Thus, miR‐100 and miR‐125b may be novel biomarkers for lymph node metastasis of early CRCs with submucosal invasion.

[The Role of MicroRNAs in Colorectal Cancer]

Colorectal cancer (CRC) is one of the leading causes of cancer related deaths in the world. Many oncogenes and tumor suppressor genes are involved in the development of CRC. MicroRNAs (miRNAs) are a class of small, non-coding, endogenous RNAs in animals and plants. Recent studies have shown that miRNAs are associated with the mediation process of tumorigenesis, including inflammation, cell cycle, stress response, differentiation, apoptosis, migration, and invasion in cancer. These miRNAs have been linked to the development of CRC and recently studied as new potential biomarkers in the diagnosis and treatment for CRC. Specific miRNAs expression patterns help distinguish CRC from other colon-related diseases, and miRNAs can target the oncogenes and regulatory molecular pathways. Recent studies have demonstrated the restoration of tumor suppressive miRNAs and inhibition of oncogenic miRNAs for CRC treatment. Herein, we describe the diagnostic and therapeutic roles of miRNAs in CRC.