miR-422a inhibits cell proliferation in colorectal cancer by targeting AKT1 and MAPK1

Metabolomics and network pharmacology-based identification of phenolic acids in Polygonatum kingianum var. grandifolium rhizomes as anti-cancer/Tumor active ingredients

Broadly targeted metabolomics techniques were used to identify phenolic acid compounds in Polygonatum kingianum var. grandifolium (PKVG) rhizomes and retrieve anti-cancer/tumor active substance bases from them. We identified potential drug targets by constructing Venn diagrams of compound and disease targets. Further, KEGG pathway analysis was performed to reveal the relevant pathways for anti-cancer/tumor activity of PKVG. Finally, we performed molecular docking to determine whether the identified proteins were targets of phenolic acid compounds from PKVG rhizome parts. The study's results revealed 71 phenolic acid compounds in PKVG rhizomes. Among them, three active ingredients and 42 corresponding targets were closely related to the anticancer/tumor activities of PKVG rhizome site phenolic acids. We identified two essential compounds and eight important targets by constructing the compound-target pathway network. 2 essential compounds were androsin and chlorogenic acid; 8 key targets were MAPK1, EGFR, PRKCA, MAPK10, GSK3B, CASP3, CASP8, and MMP9. The analysis of the KEGG pathway identified 42 anti-cancer/tumor-related pathways. In order of degree, we performed molecular docking on two essential compounds and the top 4 targets, MAPK1, EGFR, PRKCA, and MAPK10, to further validate the network pharmacology screening results. The molecular docking results were consistent with the network pharmacology results. Therefore, we suggest that the phenolic acids in PKVG rhizomes may exert anti-cancer/tumor activity through a multi-component, multi-target, and multi-channel mechanism of action.

The microRNA Let-7 and its exosomal form: Epigenetic regulators of gynecological cancers

Many types of gynecological cancer (GC) are often silent until they reach an advanced stage, and are therefore often diagnosed too late for effective treatment. Hence, there is a real need for more efficient diagnosis and treatment for patients with GC. During recent years, researchers have increasingly studied the impact of microRNAs cancer development, leading to a number of applications in detection and treatment. MicroRNAs are a particular group of tiny RNA molecules that regulate regular gene expression by affecting the translation process. The downregulation of numerous miRNAs has been observed in human malignancies. Let-7 is an example of a miRNA that controls cellular processes as well as signaling cascades to affect post-transcriptional gene expression. Recent research supports the hypothesis that enhancing let-7 expression in those cancers where it is downregulated may be a potential treatment option. Exosomes are tiny vesicles that move through body fluids and can include components like miRNAs (including let-7) that are important for communication between cells. Studies proved that exosomes are able to enhance tumor growth, angiogenesis, chemoresistance, metastasis, and immune evasion, thus suggesting their importance in GC management.

LncRNA FOXD1-AS1 regulates pancreatic cancer stem cell properties and 5-FU resistance by regulating the miR-570-3p/SPP1 axis as a ceRNA

Cancer stem cells (CSCs) play a pivotal role in the pathogenesis of human cancers. Previous studies have highlighted the role of long non-coding RNA (lncRNA) in modulating the stemness of CSCs. In our investigation, we identified an upregulation of lncRNA FOXD1-AS1 in CSCs. The enforced expression of lncRNA FOXD1-AS1 promotes tumorigenesis and self-renewal in pancreatic cancer CSCs. Conversely, the knockdown of lncRNA FOXD1-AS1 inhibits tumorigenesis and self-renewal in pancreatic cancer CSCs. Furthermore, our findings reveal that lncRNA FOXD1-AS1 enhances self-renewal and tumorigenesis in pancreatic cancer CSCs by up-regulating osteopontin/secreted phosphoprotein 1(SPP1) and acting as a ceRNA to sponge miR-570-3p in pancreatic cancer (PC) CSCs. Additionally, lncRNA FOXD1-AS1 depleted pancreatic cancer cells exhibit heightened sensitivity to 5-FU-indued cell growth inhibition and apoptosis. Analysis of patient-derived xenografts (PDX) indicates that a low level of lncRNA FOXD1-AS1 may serve as a predictor of 5-FU benefits in PC patients. Moreover, the introduction of SPP1 can reverse the sensitivity of lncRNA FOXD1-AS1-knockdown PC cells to 5-FU-induced cell apoptosis. Importantly, molecular studies have indicated that the elevated levels of lncRNAFOXD1-AS1 in PC are facilitated through METTL3 and YTHDF1-dependent m6A methylation. In summary, our results underscore the critical functions of lncRNA FOXD1-AS1 in the self-renewal and tumorigenesis of pancreatic cancer CSCs, positioning lncRNA FOXD1-AS1 as a promising therapeutic target for PC.

Novel insights on perils and promises of miRNA in understanding colon cancer metastasis and progression

Colorectal cancer (CRC) is the third highest frequent malignancy and ultimate critical source of cancer-associated mortality around the world. Regardless of latest advances in molecular and surgical targeted medicines that have increased remedial effects in CRC patients, the 5-year mortality rate for CRC patients remains dismally low. Evidence suggests that microRNAs (miRNAs) execute an essential part in the development and spread of CRC. The miRNAs are a type of short non-coding RNA that exhibited to control the appearance of tumor suppressor genes and oncogenes. miRNA expression profiling is already being utilized in clinical practice as analytical and prognostic biomarkers to evaluate cancer patients' tumor genesis, advancement, and counteraction to drugs. By modulating their target genes, dysregulated miRNAs are linked to malignant characteristics (e.g., improved proliferative and invasive capabilities, cell cycle aberration, evasion of apoptosis, and promotion of angiogenesis). This review presents an updated summary of circulatory miRNAs, tumor-suppressive and oncogenic miRNAs, and the potential reasons for dysregulated miRNAs in CRC. Further we will explore the critical role of miRNAs in CRC drug resistance.

Deregulation of the miR-19b/PPP2R5E Signaling Axis Shows High Functional Impact in Colorectal Cancer Cells

MicroRNA (miR)-19b is deregulated in colorectal cancer (CRC) and locally advanced rectal cancer (LARC), predicting worse outcome and disease progression in CRC patients, and acting as a promising prognostic marker of patient recurrence and pathological response to 5-fluorouracil (5-FU)-based neoadjuvant chemoradiotherapy in LARC. Moreover, there is a strong inverse correlation between miR-19b and PPP2R5E in LARC, and both predict the response to neoadjuvant therapy in LARC patients. However, the functional role of the miR-19b/PPP2R5E axis in CRC cells remains to be experimentally evaluated. Here, we confirm with luciferase assays that miR-19b is a direct negative regulator of PPP2R5E in CRC, which is concordant with the observed decreased PP2A activity levels after miR-19b overexpression. Furthermore, PPP2R5E downregulation plays a key role mediating miR-19b-induced oncogenic effects, increasing cell viability, colonosphere formation ability, and the migration of CRC cells. Lastly, we also confirm the role of miR-19b mediating 5-FU sensitivity of CRC cells through negative PPP2R5E regulation. Altogether, our findings demonstrate the functional relevance of the miR-19b/PPP2R5E signaling pathway in disease progression, and its potential therapeutic value determining the 5-FU response of CRC cells.

LncRNA DICER1-AS1 promotes colorectal cancer progression by activating the MAPK/ERK signaling pathway through sponging miR-650

BACKGROUND

Colorectal cancer (CRC) is a disease with high morbidity and mortality rates globally. Long noncoding RNAs (lncRNAs) play a fundamental role in tumor progression, and increasing attention has been paid to their role in CRC. This study aimed to determine the function of lncRNA DICER1 antisense RNA 1 (DICER1-AS1) in CRC and confirm its potential regulatory mechanisms in CRC.

METHODS

The publicly available dataset was used to assess DICER1-AS1 function and expression in CRC. RT-qPCR or western blot assays were performed to verify DICER1-AS1, miR-650, and mitogen-activated protein kinase 1 (MAPK1) expression in CRC cells or tissues. To determine the function of DICER1-AS1, we performed CCK-8, colony formation, transwell, cell cycle, and in vivo animal assays. Using RNA sequence analysis, luciferase reporter assays, and bioinformatics analysis, the connection between DICER1-AS1, MAPK1, and miR-650 was investigated.

RESULTS

DICER1-AS1 was significantly upregulated in CRC tissue compared to normal colon tissue. High DICER1-AS1 expression suggested a poor prognosis in CRC patients. Functionally, upregulation of DICER1-AS1 effectively promoted CRC proliferation, migration, and invasion ex vivo and tumor progression in vivo. Mechanistically, DICER1-AS1 functions as a competitive endogenous RNA (ceRNA) that sponges miR-650 to upregulate MAPK1, promotes ERK1/2 phosphorylation, and sequentially activates the MAPK/ERK signaling pathway.

CONCLUSION

Our investigations found that upregulation of DICER1-AS1 activates the MAPK/ERK signaling pathway by sponging miR-650 to promote CRC progression, revealing a possible clinically significant biomarker and therapeutic target.

Anti-colorectal cancer of Ardisia gigantifolia Stapf. and targets prediction via network pharmacology and molecular docking study

BACKGROUND

Ardisia gigantifolia Stapf. (AGS), a Chinese folk medicine widely grows in the south of China and several studies reported that AGS could inhibit the proliferation of breast cancer, liver cancer, and bladder cancer cell lines. However, little is known about its anti-colorectal cancer (CRC) efficiency.

METHODS

In the present study, a combination of MTT assay, network pharmacological analysis, bioinformatics, molecular docking, and molecular dynamics simulation study was used to investigate the active ingredients, and targets of AGS against CRC, as well as the potential mechanism.

RESULTS

MTT assay showed that three kinds of fractions from AGS, including the n-butanol extract (NBAGS), ethyl acetate fraction (EAAGS), and petroleum ether fraction (PEAGS) significantly inhibited the proliferation of CRC cells, with the IC₅₀ values of 197.24, 264.85, 15.45 µg/mL on HCT116 cells, and 523.6, 323.59, 150.31 µg/mL on SW620 cells, respectively. Eleven active ingredients, including, 11-O-galloylbergenin, 11-O-protocatechuoylbergenin, 11-O-syringylbergenin, ardisiacrispin B, bergenin, epicatechin-3-gallate, gallic acid, quercetin, stigmasterol, stigmasterol-3-o-β-D-glucopyranoside were identified. A total of 173 targets related to the bioactive components and 21,572 targets related to CRC were picked out through database searching. Based on the crossover targets of AGS and CRC, a protein-protein interaction network was built up by the String database, from which it was concluded that the core targets would be SRC, MAPK1, ESR1, HSP90AA1, MAPK8. Besides, GO analysis showed that the numbers of biological process, cellular component, and molecular function of AGS against CRC were 1079, 44, and 132, respectively, and KEGG pathway enrichment indicated that 96 signaling pathways in all would probably be involved in AGS against CRC, among which MAPK signaling pathway, lipid, and atherosclerosis, proteoglycans in cancer, prostate cancer, adherens junction would probably be the major pathways. The docking study verified that AGS had multiple ingredients and multiple targets against CRC. Molecular dynamics (MD) simulation analysis showed that the binding would be stable via forming hydrogen bonds.

CONCLUSION

Our study showed that AGS had good anti-CRC potency with the characteristics of multi-ingredients, -targets, and -signaling pathways.

miR-451a suppresses papillary thyroid cancer cell proliferation and invasion and facilitates apoptosis through targeting DCBLD2 and AKT1

Papillary thyroid cancer (PTC) is a common malignancy. MicroRNAs (miRNAs) may act as oncogenes or tumor suppressor genes. However, the role of miR-451a in PTC is not fully understood. Hence, the objective of the study was to research the effect and mechanism of miR-451a in PTC. Differentially expressed miRNAs between GSE113629 and GSE103996 databases were assessed by Venn diagram. miR-451a and its downstream target genes were assessed by RT-PCR and Western blot. The proliferation, invasion, and apoptosis were determined by CCK-8, EdU, transwell, and flow cytometry assays. Dual-luciferase reporter assay were used to evaluated the target of miR-451a. Xenografted tumors was used to explore the function of miR-451a in vivo. Pathological changes and related protein expression were measured by HE staining and immunohistochemistry. MiR-451a was downregulated in PTC tissues and blood, and low expression of miR-451a was related to short overall survival, serious lymph node metastasis and high TNM grade in PTC patients. Moreover, increase of miR-451a restrained the proliferation and invasion and accelerated the apoptosis. Furthermore, miR-451a repressed VEGF signaling pathway. Importantly, miR-451a was demonstrated to target DCBLD2 and AKT1. Overexpression of DCBLD2 and AKT1 could restore the effect of miR-451a on PTC cells. In addition, miR-451a reduced the growth of xenografted tumors in vivo. The data suggested that miR-451a attenuated the proliferation, invasion and promoted apoptosis in PTC cells via inhibiting DCBLD2 and AKT1.

MicroRNA panels as diagnostic biomarkers for colorectal cancer: A systematic review and meta-analysis

Background

Circulating microRNAs (miRNA) have emerged as promising diagnostic biomarkers for several diseases, including cancer. However, the diagnostic accuracy of miRNA panels in colorectal cancer (CRC) remains inconsistent and there is still lack of meta-analyses to determine whether miRNA panels can serve as robust biomarkers for CRC diagnosis.

Methods

This study performed a systematic review and meta-analysis to evaluate the clinical utility of miRNA panels as potential biomarkers for the diagnosis of CRC. The investigation systematically searched PubMed, Medline, Web of Science, Cochrane Library, and Google Scholar (21-year span, between 2000 and 2021) to retrieve articles reporting the diagnostic role of miRNA panels in detecting CRC. Diagnostic meta-analysis of miRNA panels used diverse evaluation indicators, including sensitivity, specificity, Positive Likelihood Ratio (PLR), Negative Likelihood Ratio (NLR), Diagnostic Odds Ratio (DOR), and the area under the curve (AUC) values.

Results

Among the 313 articles identified, 20 studies met the inclusion criteria. The pooled estimates of miRNA panels for the diagnosis of CRC were 0.85 (95% CI: 0.84-0.86), 0.79 (95% CI: 0.78-0.80), 4.06 (95% CI: 3.89-4.23), 0.20 (95% CI: 0.19-0.20), 22.50 (95% CI: 20.81-24.32) for sensitivity, specificity, PLR, NLR, and DOR, respectively. Moreover, the summary receiver operating characteristics (SROC) curve revealed an AUC value of 0.915 (95% CI: 0.914-0.916), suggesting an outstanding diagnostic accuracy for overall miRNA panels. Subgroup and meta-regression analyses demonstrated that miRNA panels have the highest diagnostic accuracy within serum samples, rather than in other sample-types - with a sensitivity, specificity, PLR, NLR, DOR, and AUC of 0.87, 0.86, 7.33, 0.13, 55.29, and 0.943, respectively. Sensitivity analysis revealed that DOR values did not differ markedly, which indicates that the meta-analysis had strong reliability. Furthermore, this study demonstrated no proof of publication bias for DOR values analyzed using Egger's regression test (P > 0.05) and funnel plot. Interestingly, miR-15b, miR-21 and miR-31 presented the best diagnostic accuracy values for CRC with sensitivity, specificity, PLR, NLR, DOR, and AUC values of 0.95, 0.94, 17.19, 0.05, 324.81, and 0.948, respectively.

Conclusion

This study's findings indicated that miRNA panels, particularly serum-derived miRNA panels, can serve as powerful and promising biomarkers for early CRC screening.

Systematic review registration

[www.crd.york.ac.uk/prospero], identifier [CRD42021268172].

Construction, bioinformatics analysis, and validation of competitive endogenous RNA networks in ulcerative colitis

Background: Ulcerative colitis (UC) is a common chronic disease of the digestive system. Recently, competitive endogenous RNAs (ceRNAs) have been increasingly used to reveal key mechanisms for the pathogenesis and treatment of UC. However, the role of ceRNA in UC pathogenesis has not been fully clarified. This study aimed to explore the mechanism of the lncRNA-miRNA-mRNA ceRNA network in UC and identify potential biomarkers and therapeutic targets.

Materials and Methods: An integrative analysis of mRNA, microRNA (miRNA), and long non-coding RNA (lncRNA) files downloaded from the Gene Expression Omnibus (GEO) was performed. Differentially expressed mRNA (DE-mRNAs), miRNA (DE-miRNAs), and lncRNA (DE-lncRNAs) were investigated between the normal and UC groups by the limma package. A weighted correlation network analysis (WGCNA) was used to identify the relative model for constructing the ceRNA network, and, concurrently, miRWalk and DIANA-LncBase databases were used for target prediction. Consecutively, the Gene Ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG) pathway, and Reactome pathway enrichment analyses, protein-protein interaction (PPI) network, Cytohubba, and ClueGO were performed to identify hub genes. Additionally, we examined the immune infiltration characteristics of UC and the correlation between hub genes and immune cells using the immuCellAI database. Finally, the expression of potential biomarkers of ceRNA was validated via qRT-PCR in an experimental UC model induced by dextran sulfate sodium (DSS).

Result: The ceRNA network was constructed by combining four mRNAs, two miRNAs, and two lncRNAs, and the receiver operating characteristic (ROC) analysis showed that two mRNAs (CTLA4 and STAT1) had high diagnostic accuracy (area under the curve [AUC] > 0.9). Furthermore, CTLA4 up-regulation was positively correlated with the infiltration of immune cells. Finally, as a result of this DSS-induced experimental UC model, CTLA4, MIAT, and several associate genes expression were consistent with the results of previous bioinformatics analysis, which proved our hypothesis.

Conclusion: The investigation of the ceRNA network in this study could provide insight into UC pathogenesis. CTLA4, which has immune-related properties, can be a potential biomarker in UC, and MIAT/miR-422a/CTLA4 ceRNA networks may play important roles in UC.

Hsa-miR-422a Originated from Short Interspersed Nuclear Element Increases ARID5B Expression by Collaborating with NF-E2

MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate the expression of target messenger RNA (mRNA) complementary to the 3' untranslated region (UTR) at the post-transcriptional level. Hsa-miR-422a, which is commonly known as miRNA derived from transposable element (MDTE), was derived from short interspersed nuclear element (SINE). Through expression analysis, hsa-miR-422a was found to be highly expressed in both the small intestine and liver of crab-eating monkey. AT-Rich Interaction Domain 5 B (ARID5B) was selected as the target gene of hsa-miR-422a, which has two binding sites in both the exon and 3'UTR of ARID5B. To identify the interaction between hsa-miR-422a and ARID5B, a dual luciferase assay was conducted in HepG2 cell line. The luciferase activity of cells treated with the hsa-miR-422a mimic was upregulated and inversely downregulated when both the hsa-miR-422a mimic and inhibitor were administered. Nuclear factor erythroid-2 (NF-E2) was selected as the core transcription factor (TF) via feed forward loop analysis. The luciferase expression was downregulated when both the hsa-miR-422a mimic and siRNA of NF-E2 were treated, compared to the treatment of the hsa-miR-422a mimic alone. The present study suggests that hsa-miR-422a derived from SINE could bind to the exon region as well as the 3'UTR of ARID5B. Additionally, hsa-miR-422a was found to share binding sites in ARID5Bwith several TFs, including NF-E2. The hsa-miR-422a might thus interact with TF to regulate the expression of ARID5B, as demonstrated experimentally. Altogether, hsa-miR-422a acts as a super enhancer miRNA of ARID5Bby collaborating with TF and NF-E2.

miRNA-Dependent Regulation of AKT1 Phosphorylation

The phosphoinositide-3-kinase (PI3K)/AKT pathway regulates cell survival and is over-activated in most human cancers, including ovarian cancer. Following growth factor stimulation, AKT1 is activated by phosphorylation at T308 and S473. Disruption of the AKT1 signaling pathway is sufficient to inhibit the epithelial-mesenchymal transition in epithelial ovarian cancer (EOC) cells. In metastatic disease, adherent EOC cells transition to a dormant spheroid state, characterized previously by low S473 phosphorylation in AKT1. We confirmed this finding and observed that T308 phosphorylation was yet further reduced in EOC spheroids and that the transition from adherent to spheroid growth is accompanied by significantly increased levels of let-7 miRNAs. We then used mechanistic studies to investigate the impact of let-7 miRNAs on AKT1 phosphorylation status and activity in cells. In growth factor-stimulated HEK 293T cells supplemented with let-7a, we found increased phosphorylation of AKT1 at T308, decreased phosphorylation at S473, and enhanced downstream AKT1 substrate GSK-3β phosphorylation. Let-7b and let-7g also deregulated AKT signaling by rendering AKT1 insensitive to growth factor simulation. We uncovered let-7a-dependent deregulation of PI3K pathway components, including PI3KC2A, PDK1, and RICTOR, that govern AKT1 phosphorylation and activity. Together, our data show a new role for miRNAs in regulating AKT signaling.

Dose-dependent expression of extracellular microRNAs in HCT116 colorectal cancer cells exposed to high-dose-rate ionising radiation

Biomarkers of tumour response to radiotherapy may help optimise cancer treatment. The aim of the present study was to identify changes in extracellular microRNAs (miRNAs) as a biomarker of radiation-induced damage to human colorectal cancer cells. HCT116 cells were exposed to increasing doses of X-rays, and extracellular miRNAs were analysed by microarray. The results were correlated with the frequency of micronuclei. A total of 59 miRNAs with a positive correlation and 4 with a negative correlation between dose (up to 6 Gy) and extracellular miRNA expression were identified. In addition, for doses between 0 and 10 Gy, 12 miRNAs among those 59 miRNAs with a positive correlation were identified; for these extracellular miRNAs, a significantly positive correlation was observed between their expression and the frequency of micronuclei for doses up to 10 Gy. These results suggest that specific miRNAs may be considered as cell damage markers and may serve as secreted radiotherapy response biomarkers for colorectal cancer; however, the results must be further validated in serum samples collected from patients undergoing radiotherapy.

Identification and functional analysis of a three-miRNA ceRNA network in hypertrophic scars

Background

Hypertrophic scar (HTS) is a fibrotic disorder of skins and may have repercussions on the appearance as well as functions of patients. Recent studies related have shown that competitive endogenous RNA (ceRNA) networks centering around miRNAs may play an influential role in HTS formation. This study aimed to construct and validate a three-miRNA (miR-422a, miR-2116-3p, and miR-3187-3p) ceRNA network, and explore its potential functions.

Methods

Quantitative real‑time PCR (qRT‑PCR) was used to compare expression levels of miRNAs, lncRNAs, and genes between HTS and normal skin. Target lncRNAs and genes of each miRNA were predicted using starBase as well as TargetScan database to construct a distinct ceRNA network; overlapping target lncRNAs and genes of the three miRNAs were utilized to develop a three-miRNA ceRNA network. For every network, protein–protein interaction (PPI) network analysis was performed to identify its hub genes. For each network and its hub genes, Gene Oncology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were conducted to explore their possible functions.

Results

MiR-422a, miR-2116-3p, and miR-3187-3p were all downregulated in HTS tissues and fibroblasts. MiR-422a-based ceRNA network consisted of 101 lncRNAs with 133 genes; miR-2116-3p-centered ceRNA network comprised 85 lncRNAs and 978 genes; miR-3187-3p-derived ceRNA network encompassed 84 lncRNAs as well as 1128 genes. The three-miRNA ceRNA network included 2 lncRNAs with 9 genes, where MAPK1, FOSL2, ABI2, KPNA6, CBL, lncRNA-KCNQ1OT1, and lncRNA-EBLN3P were upregulated. According to GO and KEGG analysis, these networks were consistently related to ubiquitination. Three ubiquitination-related genes (CBL, SMURF2, and USP4) were upregulated and negatively correlated with the expression levels of the three miRNAs in HTS tissues.

Conclusions

This study identified a three-miRNA ceRNA network, which might take part in HTS formation and correlate with ubiquitination.

Circular RNA Foxo3 enhances progression of ovarian carcinoma cells

Background: Ovarian carcinoma (OC) is the deadliest gynecologic malignancy in females worldwide. Circular RNA Foxo3 (Foxo3) plays essential roles in various cancers. However, the detailed function of Foxo3 in OC remains unclear. This study aimed to investigate the role of Foxo3 in OC and the underlying molecular mechanism.

Methods: The abundance of Foxo3 was detected in OC cell lines by qPCR. Lentivirus transduction, CCK-8, wound healing assays, transwell migration and invasion assays, luciferase reporter assay, western blotting, fluorescence in situ hybridization (FISH), transmission electron microscopy, nanoparticle tracking analysis, and bioinformatics analysis were performed to investigate the underlying mechanism.

Results: The results demonstrated that Foxo3 was significantly upregulated in OC cell lines. Overexpression and knockdown of Foxo3 promoted and inhibited the proliferation, migration, and invasion of OC cells, respectively. Foxo3 could bind to miR-422a to negatively regulate miR-422a expression. Also, proteolipid protein 2 (PLP2) was a targeting gene of miR-422a. Additionally, Foxo3 was highly expressed in exosomes derived from OC cells. Furthermore, Foxo3 could be shuttled to OC cells by exosomes and promoted OC progression.

Conclusions: Foxo3 promoted OC progression through exosome-mediated intercellular interaction to target miR-422a/PLP2 axis. Foxo3 may serve as a potential biomarker for OC.

LncRNA LBX2-AS1 promotes colorectal cancer progression and 5-fluorouracil resistance

BACKGROUND

Recent reports suggest that the long non-coding RNA LBX2 antisense RNA 1 (LBX2-AS1) acts as an important regulator in cancer progression, but its significance in colorectal cancer (CRC) remains undetermined.

METHODS

LBX2-AS1 expression levels in CRC were determined from the GEPIA database and CRC tissues to investigate clinical relevance. meRIP-PCR assays investigated the molecular mechanisms underlying the function of m6A in LBX2-AS1. Loss of function experiments was used to define the role of LBX2-AS1 in the progression of CRC. The ceRNA function of LBX2-AS1 was evaluated by RNA immunoprecipitation. In vitro and PDX models were used to determine if LBX2-AS1 promotes 5-fluorouracil resistance.

RESULTS

Data from the TCGA and our institutional patient cohorts established that LBX2-AS1 levels were significantly upregulated in most CRC tissues relative to normal adjacent colon tissues. Moreover, LBX2-AS1 levels were positively correlated with aggressive disease characteristics, constituting an independent prognostic indicator of overall patient survival. Mechanistic investigations suggested that the increased LBX2-AS1 in CRC was mediated by METTL3-dependent m6A methylation. In vitro experiments indicated that knockdown of LBX2-AS1 inhibited CRC proliferation, migration and invasion with this phenotype linked to LBX2-AS1-mediated regulation of AKT1, acting as a ceRNA to sponge miR-422a. Ex vivo analysis of patient-derived CRC xenografts showed that low LBX2-AS1 expression cases exhibited 5-FU responsiveness and clinical investigations confirmed that low LBX2-AS1 expression was associated with improved clinical benefits from 5-FU therapy.

CONCLUSIONS

Together these results suggest that LBX2-AS1 may serve as a therapeutic target and predictor of 5-FU benefit in CRC patients.

Knockdown of lncRNA PVT1 inhibits the proliferation and accelerates the apoptosis of colorectal cancer cells via the miR‑761/MAPK1 axis

Colorectal cancer (CRC) is associated with high morbidity rates. Long non‑coding RNAs (lncRNAs) participate in the development of CRC. However, the potential roles of lncRNA plasmacytoma variant translocation 1 (PVT1) in CRC remain unknown. Therefore, the aim of the present study was to investigate the potential roles of PVT1 in CRC. Reverse transcription‑quantitative PCR and western blot analyses were conducted to determine the mRNA and protein expression levels. The cellular behaviors were detected using 5‑Ethynyl‑2'‑deoxyuridine, Cell Counting Kit‑8 and flow cytometry assays. The interaction between PVT1 and microRNA (miR)‑761 or MAPK1 was confirmed using a dual‑luciferase reporter assay. Moreover, the Pearson's method was applied for correlation analysis. The results demonstrated that the expression levels of PVT1 and MAPK1 were upregulated, while miR‑761 was downregulated in CRC tissues. The expression of PVT1 was positively correlated with MAPK1 and negatively correlated with miR‑761. In addition, PVT1 sponged miR‑761 to upregulate MAPK1 expression. It was found that the knockdown of PVT1 expression inhibited the proliferation and promoted the apoptosis of CRC cells, which was more potent in cells transfected with miR‑761. The regulatory role of small interfering RNA‑PVT1 on the expression of apoptosis‑related genes was reduced by MAPK1. Collectively, the present results suggested that knockdown of PVT1 may inhibit the progression of CRC by regulating the miR‑761/MAPK1 axis, which may provide a promising biomarker for the treatment of CRC.

Long noncoding RNA LINC00958 suppresses apoptosis and radiosensitivity of colorectal cancer through targeting miR-422a

Background

Long noncoding RNAs (lncRNAs) have been elucidated to participate in the development and progression of various cancers. In this study, we aimed to explore the underlying functions and mechanisms of LINC00958 in colorectal cancer.

Methods

LINC00958 expression in colorectal cancer tissues was examined by qRT-PCR. The correlations between LINC00958 expression and clinical characteristics and prognosis were evaluated. The biological functions of LINC00958 were detected by CCK-8, MTT, colony formation and flow cytometric analyses. RNA pulldown, RIP and luciferase reporter assays were used to confirm the regulatory effects of LINC00958 on miR-422a. Rescue experiments were performed to detect the effects of miR-422a on the roles of LINC00958.

Results

LINC00958 was upregulated in colorectal cancer tissues and cell lines. High LINC00958 levels were positively associated with T stage and predicted poor prognosis. Cell experiments showed that LINC00958 promoted cell proliferation and suppressed apoptosis and sensitivity to radiotherapy in vitro and promoted tumor growth in vivo. Bioinformatics analysis predicted the binding site of miR-422a on LINC00958. Mechanistically, RNA pulldown, RIP and luciferase reporter assays demonstrated that LINC00958 specifically targeted miR-422a. In addition, we found that miR-422a suppressed MAPK1 expression by directly binding to the 3’-UTR of MAPK1, thereby inhibiting cell proliferation and enhancing cell apoptosis and radiosensitivity. Furthermore, miR-422a rescued the roles of LINC00958 in promoting MAPK1 expression and cell proliferation and decreasing cell apoptosis and radiosensitivity.

Conclusions

LINC00958 promoted MAPK1 expression and cell proliferation and suppressed cell apoptosis and radiosensitivity by targeting miR-422a, which suggests that it is a potential biomarker for the prognosis and treatment of colorectal cancer.

Circ_0000317/microRNA-520g/HOXD10 axis affects the biological characteristics of colorectal cancer

Circular RNAs (circRNAs) are a class of noncoding RNAs that are widely expressed in cancer tissues and play a pro- or anticancer role in modulating cancer progression. This work is aimed to probe the biological role of circ_0000317 in colorectal cancer (CRC) and its underlying mechanism. Circ_0000317 was selected from the circRNA microarray datasets (GSE121895). Quantitative real-time polymerase chain reaction was utilized to examine circ_0000317, microRNA (miR)-520g, and homeobox D10 (HOXD10) mRNA expression in CRC. Cell Counting Kit-8 and Transwell experiments were conducted to examine the effects of circ_0000317 on proliferation, migration, and invasion of CRC cells. Bioinformatic analysis and dual-luciferase reporter gene experiments were implemented to predict and validate the targeting relationship between circ_0000317 and miR-520g, miR-520g, and HOXD10. Western blot was employed to examine HOXD10 expression at protein level in CRC cells. Circ_0000317 and HOXD10 mRNA expression were unveiled to be down-modulated and miR-520g expression was up-modulated in CRC. Functionally, circ_0000317 overexpression repressed CRC cell proliferation, migration, and invasion. Mechanistically, miR-520g was a direct target of circ_0000317 and miR-520g specifically modulated HOXD10 expression. Furthermore, miR-520g mimics partially counteracted the suppressing effect of circ_0000317 on malignant phenotype of CRC cells. Circ_0000317 represses CRC progression by targeting miR-520g and modulating HOXD10 expression. Hence, circ_0000317 may be a promising diagnostic biomarker and a therapeutic target for CRC.

miR-1250-5p is a novel tumor suppressive intronic miRNA hypermethylated in non-Hodgkin's lymphoma: novel targets with impact on ERK signaling and cell migration

Background

miR-1250 is localised to the second intron of AATK at chromosome 17q25. As a CpG island is present at the putative promoter region of its host gene, AATK, we postulated that the intronic miR-1250-5p is a tumor suppressor miRNA co-regulated with its host gene, AATK, by promoter DNA methylation in non-Hodgkin’s lymphoma (NHL).

Methods

AATK/miR-1250 methylation was studied in healthy controls, including ten normal peripheral blood buffy coats and eleven normal tonsils, ten lymphoma cell lines, and 120 primary lymphoma samples by methylation-specific PCR (MSP). The expression of miR-1250-5p and AATK was investigated by quantitative real-time PCR. Tumor suppressor properties of miR-1250-5p were demonstrated by over-expression of precursor miR-1250-5p in lymphoma cells. The target of miR-1250-5p was verified by luciferase reporter assay.

Results

AATK/miR-1250 methylation was absent in healthy peripheral blood and tonsils, but detected in five (50%) NHL cell lines. AATK/miR-1250 methylation correlated with repression of miR-1250-5p and AATK in NHL cell lines. In completely methylated SU-DHL-6 and SUP-T1 cells, treatment with 5-AzadC led to promoter demethylation and re-expression of both miR-1250-5p and AATK. In primary lymphoma samples, AATK/miR-1250 was frequently methylated in B-cell lymphoma (n = 41, 44.09%) and T-cell lymphoma (n = 9, 33.33%) with a comparable frequency (P = 0.318). In SU-DHL-6 and SU-DHL-1 cells, restoration of miR-1250-5p resulted in decreased cellular proliferation by MTS assay, increased cell death by trypan blue staining and enhanced apoptosis by annexin V-PI assay. Moreover, MAPK1 and WDR1 were verified as direct targets of miR-1250-5p by luciferase assay. In 39 primary NHLs, miR-1250-5p expression was shown to be inversely correlated with each of MAPK1 (P = 0.05) and WDR1 (P = 0.031) by qRT-PCR. Finally, in SU-DHL-1 cells, overexpression of miR-1250-5p led to repression of MAPK1 and WDR1 at both transcript and protein levels, with downregulation of phospho-ERK2 by Western-blotting and inhibition of SDF-1-dependent cell migration by transwell assay.

Conclusions

miR-1250-5p is a novel tumor suppressive intronic miRNA co-regulated and silenced by promoter DNA methylation of its host gene AATK in NHL. MAPK1 and WDR1 are novel miR-1250-5p direct targets rendering inhibition of MAPK/ERK signaling and SDF-1-dependent cell migration, hence implicated in survival and dissemination of lymphoma.

Downregulation of long non‑coding RNA GACAT1 suppresses proliferation and induces apoptosis of NSCLC cells by sponging microRNA‑422a

Increasing evidence has demonstrated the important roles of long non‑coding (lnc) RNA in non‑small cell lung cancer (NSCLC). lncRNA gastric cancer‑associated transcript 1 (GACAT1) has been reported to play an oncogenic role in different types of cancer; however, the function of GACAT1 in NSCLC remains unclear. The present study found that GACAT1 was overexpressed in NSCLC tissues and was associated with poor outcomes in patients with NSCLC. Functional experiments revealed that GACAT1 downregulation inhibited proliferation, induced apoptosis and cell cycle arrest of 2 NSCLC cell lines. GACAT1 was found to target microRNA(miR)‑422a mechanically and negatively regulated miR‑422a expression. Reduced expression of miR‑422a in NSCLC tissues was inversely correlated with that of GACAT1. Furthermore, YY1 transcription factor (YY1) was identified as a downstream miR‑422a target. Reduced expression of GACAT1 inactivated YY1 by sponging miR‑422a in NSCLC cells. YY1 reintroduction reversed the reduced proliferation of NSCLC cells via GACAT1 knockdown. Taken together, these results revealed the novel role of the GACAT1/miR‑422a pathway in the progression of NSCLC cell lines, providing a possible therapeutic strategy for NSCLC treatment.

Cytochrome C Oxidase Assembly Factor 1 Homolog Predicts Poor Prognosis and Promotes Cell Proliferation in Colorectal Cancer by Regulating PI3K/AKT Signaling

Purpose

Colorectal cancer (CRC) is one of the most common malignancies in the world. The prognosis of advanced CRC is still poor. The purpose of this study was to identify a gene expression profile associated with CRC that may contribute to the early diagnosis of CRC and improve patient prognosis.

Patients and Methods

Five pairs of CRC tissues and paracancerous tissues were used to identify causative genes using microarray assays. The prognostic value of Cytochrome C Oxidase Assembly Factor 1 Homolog (COA1) in CRC was assessed in 90 CRC patients. Loss-of-function assays, cell proliferation assays using Celigo and MTT, colony formation assays, a subcutaneous xenograft mouse model, and apoptosis assays were used to define the effects of downregulation of COA1 in CRC cells in vitro and in vivo. The underlying molecular mechanisms of COA1 in CRC were also investigated.

Results

The causative gene COA1 was identified through microarray analysis. COA1 expression in CRC was notably associated with pathologic differentiation, tumor size, and tumor depth. COA1 expression may act as an independent prognostic factor for overall survival of CRC. Knockdown of COA1 inhibited the proliferation of CRC cells in vitro and the tumorigenicity of CRC cells in vivo. Decreased COA1 expression induced apoptosis of CRC cells. Based on the microarray assay results comparing HCT116 cells transfected with lentivirus encoding anti-COA1 shRNA or negative control shRNA, ingenuity pathway analysis (IPA) revealed that the PI3K/AKT signaling pathway was significantly enriched. Moreover, CCND1, mTOR, AKT1, and MDM2 were identified as the downstream genes of COA1.

Conclusion

These findings demonstrate that COA1 promotes CRC cell proliferation and inhibits apoptosis by regulating the PI3K/AKT signaling pathway. Our results implicate COA1 as a potential oncogene involved in tumor growth and progression of CRC.

Circular RNA NOX4 promotes the development of colorectal cancer via the microRNA‑485‑5p/CKS1B axis

Colorectal cancer (CRC) is a common malignancy globally. The aim of the present study was to explore the role and the working mechanism of circular RNA NADPH oxidase 4 (circNOX4; circBase ID, hsa_circ_0023990) in CRC. Reverse transcription‑quantitative (RT‑q)PCR was used to examine the expression of circNOX4, NOX4 mRNA and microRNA (miR)‑485‑5p in CRC tissues and cell lines. 3‑(4,5‑Dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide and Transwell assays were performed to analyze CRC cell viability and motility. The glycolytic ability of CRC cells was assessed by measuring glucose consumption, lactate production, extracellular acidification and O2 consumption rates using commercial kits. The starBase database was used to predict the targets of circNOX4 and miR‑485‑5p, and the interaction was confirmed by dual‑luciferase reporter and RNA immunoprecipitation assays. A murine xenograft model was established to verify the role of circNOX4 in CRC in vivo. The results demonstrated that the expression of circNOX4 was upregulated in CRC tissues and cell lines compared with that in adjacent normal tissues and a normal colon epithelial cell line, respectively. The expression of circNOX4 was negatively associated with the prognosis of patients with CRC. CircNOX4 silencing suppressed the proliferation, migration, invasion and glycolysis of CRC cells. miR‑485‑5p was identified as a target of circNOX4. CircNOX4 promoted CRC progression by sponging miR‑485‑5p. miR‑485‑5p was demonstrated to bind to the 3' untranslated region (UTR) of CDC28 protein kinase regulatory subunit 1B (CKS1B). miR‑485‑5p overexpression‑mediated malignant properties of CRC cells were partly reversed by the transfection with the CKS1B overexpression plasmid. CircNOX4 silencing restrained the CRC xenograft growth in vivo. Collectively, the results of the present study demonstrated that circNOX4 may serve an oncogenic role in CRC by promoting the proliferation, migration, invasion and glycolysis of CRC cells via the miR‑485‑5p/CKS1B axis.

MicroRNA‑422a functions as a tumor suppressor in glioma by regulating the Wnt/β‑catenin signaling pathway via RPN2

MicroRNAs (miRs), which act as crucial regulators of oncogenes and tumor suppressors, have been confirmed to play a significant role in the initiation and progression of various malignancies, including glioma. The present study analyzed the expression and roles of miR‑422a in glioma, and reverse transcription‑quantitative PCR confirmed that miR‑422a expression was significantly lower in glioblastoma multiforme (GBM) samples and cell lines compared with the low‑grade glioma samples and the H4 cell line, respectively. miR‑422a overexpression suppressed proliferation and invasion, and induced apoptosis in LN229 and U87 cell lines. Luciferase reporter assay, western blotting and RNA immunoprecipitation analysis revealed that ribophorin II (RPN2) is a direct functional target of miR‑422a. Additionally, the overexpression of RPN2 partially reversed the miR‑422a‑mediated inhibitory effect on the malignant phenotype. Mechanistic investigation demonstrated that the upregulation of miR‑422a inhibited β‑catenin/transcription factor 4 transcriptional activity, at least partially through RPN2, as indicated by in vitro and in vivo experiments. Furthermore, RPN2 expression was inversely correlated with miR‑422a expression in GBM specimens and predicted patient survival in the Chinese Glioma Genome Atlas, UALCAN, Gene Expression Profiling Interactive Analysis databases. In conclusion, the present data reveal a new miR‑422a/RPN2/Wnt/β‑catenin signaling axis that plays critical roles in glioma tumorigenesis, and it represents a potential therapeutic target for GBM.

LncRNA EIF3J-AS1 enhanced esophageal cancer invasion via regulating AKT1 expression through sponging miR-373-3p

Esophageal cancer (ECa) remains a major cause of mortality across the globe. The expression of EIF3J-AS1 is altered in a plethora of tumors, but its role in ECa development and progression are undefined. Here, we show that EIF3J-AS1 is up-regulated in ECa and that its expression correlates with advanced TNM stage (P = 0.014), invasion depth (P = 0.001), positive lymph node metastasis (P < 0.001) and poor survival (OS: P = 0.0059; DFS: P = 0.0037) in ECa. Functional experiments showed that knockdown EIF3J-AS1 inhibited ECa growth and metastasis through in vitro and in vivo experiments. Regarding the mechanism, EIF3J-AS1/miR-373-3p/AKT1 established the ceRNA network involved in the modulation of cell progression of ECa cells. Overall, EIF3J-AS1 may exhibit an oncogenic function in ECa via acting as a sponge for miR-373-3p to up-regulate AKT1 mRNA level, and may serve as a potential therapeutic target and a prognostic biomarker for ECa patients.

Nongenomic Actions of Thyroid Hormone: The Integrin Component

The extracellular domain of plasma membrane integrin αvβ3 contains a cell surface receptor for thyroid hormone analogues. The receptor is largely expressed and activated in tumor cells and rapidly dividing endothelial cells. The principal ligand for this receptor is l-thyroxine (T₄), usually regarded only as a prohormone for 3,5,3'-triiodo-l-thyronine (T₃), the hormone analogue that expresses thyroid hormone in the cell nucleus via nuclear receptors that are unrelated structurally to integrin αvβ3. At the integrin receptor for thyroid hormone, T₄ regulates cancer and endothelial cell division, tumor cell defense pathways (such as anti-apoptosis), and angiogenesis and supports metastasis, radioresistance, and chemoresistance. The molecular mechanisms involve signal transduction via mitogen-activated protein kinase and phosphatidylinositol 3-kinase, differential expression of multiple genes related to the listed cell processes, and regulation of activities of other cell surface proteins, such as vascular growth factor receptors. Tetraiodothyroacetic acid (tetrac) is derived from T₄ and competes with binding of T₄ to the integrin. In the absence of T₄, tetrac and chemically modified tetrac also have anticancer effects that culminate in altered gene transcription. Tumor xenografts are arrested by unmodified and chemically modified tetrac. The receptor requires further characterization in terms of contributions to nonmalignant cells, such as platelets and phagocytes. The integrin αvβ3 receptor for thyroid hormone offers a large panel of cellular actions that are relevant to cancer biology and that may be regulated by tetrac derivatives.

Long noncoding RNA DUXAP8 contributes to the progression of hepatocellular carcinoma via regulating miR-422a/PDK2 axis

Background

Hepatocellular carcinoma (HCC) is one of the most deadly cancer worldwide. Multiple long noncoding RNAs (lncRNAs) are recently identified as crucial oncogenic factors or tumor suppressors. In this study, we explored the functon and mechanism of lncRNA double homeobox A pseudogene 8 (DUXAP8) in the progression of HCC.

Methods

Expression levels of DUXAP8 in HCC tissue samples were measured using qRT‐PCR. The association between pathological indexes and the expression of DUXAP8 was also analyzed. Human HCC cell lines SMMC‐7721 and QSG‐7701 were used in in vitro studies. CCK‐8 assay was used to assess the effect of DUXAP8 on HCC cell line proliferation. Scratch healing assay and Transwell assay were conducted to detect the effect of DUXAP8 on migration and invasion. Furthermore, dual‐luciferase reporter assay was used to confirm targeting relationship between miR‐422a and DUXAP8. Additionally, Western blot was used to detect the regulatory function of DUXAP8 on pyruvate dehydrogenase kinase 2 (PDK2).

Results

DUXAP8 expression HCC clinical samples was significantly increased and this was correlated with unfavorable pathological indexes. High expression of DUXAP8 was associated with shorter overall survival time of patients. Its overexpression remarkably facilitated the proliferation, metastasis, and epithelial‐mesenchymal transition of HCC cells. Accordingly, knockdown of it suppressed the malignant phenotypes of HCC cells. Overexpression of DUXAP8 significantly reduced the expression of miR‐422a by sponging it, but enhanced the expression of PDK2.

Conclusions

DUXAP8 was a sponge of tumor suppressor miR‐422a in HCC, enhanced the expression of PDK2 indirectly, and functioned as an oncogenic lncRNA.

Inhibition of miR-378a-3p by Inflammation Enhances IL-33 Levels: A Novel Mechanism of Alarmin Modulation in Ulcerative Colitis

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) characterized by mucosa damage associated with an uncontrolled inflammatory response. This immunological impairment leads to altered inflammatory mediators such as IL-33, which is shown to increase in the mucosa of active UC (aUC) patients. MicroRNAs present a distorted feature in inflamed colonic mucosa and are potential IL-33 regulating candidates in UC. Therefore, we studied the microRNA and mRNA profiles in inflamed colonic samples of UC patients, evaluating the effect of a microRNA (selected by in silico analysis and its expression in UC patients), on IL-33 under inflammatory conditions. We found that inflamed mucosa (n = 8) showed increased expression of 40 microRNAs and 2,120 mRNAs, while 49 microRNAs and 1,734 mRNAs were decreased, as determined by microarrays. In particular, IL-33 mRNA showed a 3.8-fold increase and eight members of a microRNA family (miR-378), which targets IL-33 mRNA in the 3'UTR, were decreased (-3.9 to -3.0 times). We selected three members of the miR-378 family (miR-378a-3p, miR-422a, and miR-378c) according to background information and interaction energy analysis, for further correlation analyses with IL-33 expression through qPCR and ELISA, respectively. We determined that aUC (n = 24) showed high IL-33 levels, and decreased expression of miR-378a-3p and miR-422a compared to inactive UC (n = 10) and controls (n = 6). Moreover, both microRNAs were inversely correlated with IL-33 expression, while miR-378c does not show a significant difference. To evaluate the effect of TNFα on the studied microRNAs, aUC patients with anti-TNF therapy were compared to aUC receiving other treatments. The levels of miR-378a-3p and miR-378c were higher in aUC patients with anti-TNF. Based on these findings, we selected miR-378a-3p to exploring the molecular mechanism involved by in vitro assays, showing that over-expression of miR-378a-3p decreased the levels of an IL-33 target sequence β-gal-reporter gene in HEK293 cells. Stable miR-378a-3p over-expression/inhibition inversely modulated IL-33 content and altered viability of HT-29 cells. Additionally, in an inflammatory context, TNFα decreased miR-378a-3p levels in HT-29 cells enhancing IL-33 expression. Together, our results propose a regulatory mechanism of IL-33 expression exerted by miR-378a-3p in an inflammatory environment, contributing to the understanding of UC pathogenesis.

Identification of key genes and pathways between type I and type II endometrial cancer using bioinformatics analysis

Endometrial carcinoma (EC) is a common malignant neoplasm of the female reproductive tract. The malignant degree of type II EC is much greater than that of type I EC, usually presenting with a high recurrence rate and a poor prognosis. Therefore, the present study aimed to examine the principal genes associated with the degree of differentiation in type I and type II EC and reveal their potential mechanisms. Differentially expressed genes (DEGs) were selected from the gene expression profiles derived from The Cancer Genome Atlas. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted. In the present study, the KEGG pathway enrichment analysis revealed that 5,962 upregulated DEGs were significantly enriched in the ‘p53 signaling pathway’ and involved in ‘lysine degradation’. In addition, 3,709 downregulated DEGs were enriched in ‘pathways in cancer’, as well as ‘tight junction regulation’, the ‘cell cycle’ and the ‘Wnt signaling pathway’. The 13 top hub genes MAPK1, PHLPP1, ESR1, MDM2, CDKN2A, CDKN1A, AURKA, BCL2L1, POLQ, PIK3R3, RHOQ, EIF4E and LATS2 were identified via the protein-protein interaction network. Furthermore, the OncoPrint algorithm from cBioPortal declared that 25% of EC cases carried genetic alterations. The altered DEGs (MAPK1, MDM2, AURKA, EIF4E and LATS2) may be involved in tumor differentiation and may be valuable diagnostic biomarkers. In conclusion, a number of principal genes were identified in the present study that may be determinants of poorly differentiated type II EC carcinogenesis, which may contribute to future research into potential molecular mechanisms. In addition, these genes may help identify candidate biomarkers and novel therapeutic targets for type II EC.

HypoxamiRs Profiling Identify miR-765 as a Regulator of the Early Stages of Vasculogenic Mimicry in SKOV3 Ovarian Cancer Cells

Vasculogenic mimicry (VM) is a novel cancer hallmark in which malignant cells develop matrix-associated 3D tubular networks with a lumen under hypoxia to supply nutrients needed for tumor growth. Recent studies showed that microRNAs (miRNAs) may have a role in VM regulation. In this study, we examined the relevance of hypoxia-regulated miRNAs (hypoxamiRs) in the early stages of VM formation. Data showed that after 48 h hypoxia and 12 h incubation on matrigel SKOV3 ovarian cancer cells undergo the formation of matrix-associated intercellular connections referred hereafter as 3D channels-like structures, which arose previous to the apparition of canonical tubular structures representative of VM. Comprehensive profiling of 754 mature miRNAs at the onset of hypoxia-induced 3D channels-like structures showed that 11 hypoxamiRs were modulated (FC>1.5; p < 0.05) in SKOV3 cells (9 downregulated and 2 upregulated). Bioinformatic analysis of the set of regulated miRNAs showed that they might impact cellular pathways related with tumorigenesis. Moreover, overall survival analysis in a cohort of ovarian cancer patients (n = 485) indicated that low miR-765, miR-193b, miR-148a and high miR-138 levels were associated with worst patients outcome. In particular, miR-765 was severely downregulated after hypoxia (FC < 32.02; p < 0.05), and predicted to target a number of protein-encoding genes involved in angiogenesis and VM. Functional assays showed that ectopic restoration of miR-765 in SKOV3 cells resulted in a significant inhibition of hypoxia-induced 3D channels-like formation that was associated with a reduced number of branch points and patterned tubular-like structures. Mechanistic studies confirmed that miR-765 decreased the levels of VEGFA, AKT1 and SRC-α transducers and exerted a negative regulation of VEGFA by specific binding to its 3'UTR. Finally, overall survival analysis of a cohort of ovarian cancer patients (n = 1435) indicates that high levels of VEGFA, AKT1 and SRC-α and low miR-765 expression were associated with worst patients outcome. In conclusion, here we reported a novel hypoxamiRs signature which constitutes a molecular guide for further clinical and functional studies on the early stages of VM. Our data also suggested that miR-765 coordinates the formation of 3D channels-like structures through modulation of VEGFA/AKT1/SRC-α axis in SKOV3 ovarian cancer cells.

Application of Artificial Neural Network in miRNA Biomarker Selection and Precise Diagnosis of Colorectal Cancer

BACKGROUND

The early diagnosis of colorectal cancer (CRC) is associated with improved survival rates, and development of novel non-invasive, sensitive, and specific diagnostic tests is highly demanded. The objective of this paper was to identify commonly circulating microRNA (miRNA) biomarkers for use in CRC diagnosis.

METHODS

An artificial neural network (ANN) model was proposed in this work. Among miRNAs retrieved from the Gene Expression Omnibus dataset, four miRNAs with the best miRNA score were selected by ANN units.

RESULTS

The simulation results showed that the designed ANN model could accurately classify the sample data into cancerous or non-cancerous. Furthermore, based on the results of evaluated ANN model, the area under the ROC curve (AUC) of the designed ANN model as well as the regression coefficient between the output of the ANN and the expected output was one. The confusion matrix of the ANN model indicated that all non-cancerous patients were predicted as normal, and the cancerous patients as cancerous.

CONCLUSION

Our findings suggest that the improved model can be used as a robust prediction toolbox for cancer diagnosis. In conclusion, by using ANN, circulatory miRNAs can be used as a non-invasive, sensitive and specific diagnostic marker.

Emerging microRNA biomarkers for colorectal cancer diagnosis and prognosis

MicroRNAs (miRNAs) are one abundant class of small, endogenous non-coding RNAs, which regulate various biological processes by inhibiting expression of target genes. miRNAs have important functional roles in carcinogenesis and development of colorectal cancer (CRC), and emerging evidence has indicated the feasibility of miRNAs as robust cancer biomarkers. This review summarizes the progress in miRNA-related research, including study of its oncogene or tumour-suppressor roles and the advantages of miRNA biomarkers for CRC diagnosis, treatment and recurrence prediction. Along with analytical technique improvements in miRNA research, use of the emerging extracellular miRNAs is feasible for CRC diagnosis and prognosis.

Contributions of Thyroid Hormone to Cancer Metastasis

Acting at a cell surface receptor on the extracellular domain of integrin αvβ3, thyroid hormone analogues regulate downstream the expression of a large panel of genes relevant to cancer cell proliferation, to cancer cell survival pathways, and to tumor-linked angiogenesis. Because αvβ3 is involved in the cancer cell metastatic process, we examine here the possibility that thyroid hormone as l-thyroxine (T4) and the thyroid hormone antagonist, tetraiodothyroacetic acid (tetrac), may respectively promote and inhibit metastasis. Actions of T4 and tetrac that are relevant to cancer metastasis include the multitude of synergistic effects on molecular levels such as expression of matrix metalloproteinase genes, angiogenesis support genes, receptor tyrosine kinase (EGFR/ERBB2) genes, specific microRNAs, the epithelial–mesenchymal transition (EMT) process; and on the cellular level are exemplified by effects on macrophages. We conclude that the thyroid hormone-αvβ3 interaction is mechanistically linked to cancer metastasis and that modified tetrac molecules have antimetastatic activity with feasible therapeutic potential.