Identification and validation of an individualized autophagy-clinical prognostic index in bladder cancer patients.

Purpose: Autophagy is a major catabolic system by which eukaryotic cells undergo self-degradation of damaged, defective, or unwanted intracellular components. An abnormal autophagic level is implicated in the pathogenesis of multiple diseases, including cancers. The aim of this study is to explore the prognostic value of autophagy in bladder cancer (BC), which is a major cause of cancer-related death globally. Patients and methods: First, 27 differentially expressed autophagy-related genes (ARGs) were identified in BC patients based on The Cancer Genome Atlas (TCGA) database. Functional enrichment analyses hinted that autophagy may act in a tumor-suppressive role in the initiation of BC. Then, the Cox proportional hazard regression model were employed to identify three key prognostic ARGs (JUN, MYC, and ITGA3), which were related with overall survival (OS) significantly in BC. The three genes represented important clinical significance and prognostic value in BC. Then a prognostic index (PI) was constructed. Results: The PI was constructed based on the three genes, and significantly stratified BC patients into high- and low-risk groups in terms of OS (HR=1.610, 95% CI=1.200-2.160, P=0.002). PI remained as an independent prognostic factor in multivariate analyses (HR=2.355, 95% CI=1.483-3.739, P<0.001). When integrated with clinical characteristics of age and stage, an autophagy-clinical prognostic index (ACPI) was finally validated, which had improved performance in predicting OS of BC patients (HR=2.669, 95% CI=1.986-3.587, P<0.001). The ACPI was confirmed in datasets of GSE13507 (HR=7.389, 95% CI=3.645-14.980, P<0.001) and GSE31684 (HR=1.665, 95% CI=0.872-3.179, P=0.122). Conclusion: This study provides a potential prognostic signature for predicting prognosis of BC patients and molecular insights of autophagy in BC.

Evaluation of miR-302b-5p expression and molecular mechanism in hepatocellular carcinoma: Findings based on RT-qPCR and in silico analysis.

BACKGROUND AND AIM: Extensive research has revealed that microRNAs (miRNAs) play a principle role in cancer, and miRNAs associated with specific cancers have also been identified. The role of microRNA (miR)-302b-5p, which is one of the miRNAs reported in association with cancer, in hepatocellular carcinoma (HCC) is still unclear. Thus, the present study aimed to reveal the expression and potential molecule mechanism of miR-302b-5p in HCC. METHODS: An extensive meta-analysis of data from real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR), Gene Expression Omnibus and ArrayExpress microarrays was used to determine the expression of miR-302b-5p in HCC tissue samples and non-cancerous liver tissue samples. The sensitivity and specificity of miR-302b-5p as an indicator of HCC was estimated by plotting the receiver operating characteristic (ROC) and summarized ROC (sROC). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were employed to unravel the molecular mechanisms and biological functions of miR-302b-5p in HCC. Further, the putative target genes of miR-302b-5p were harvested based on the predicted genes and differentially expressed genes in HCC. Finally, the protein-protein interaction (PPI) network was built to determine the hub genes. RESULTS: According to the RT-qPCR results, the expression of miR-302b-5p was pronouncedly decreased in 39 HCC tissue samples as compared to 39 non-cancerous liver tissue samples. The standard mean difference (SMD) values of all the samples used in the meta-analysis also indicated lower miR-302b-5p expression in the 558 HCC tissue samples than in the 286 non-cancerous liver tissue samples. ROC and sROC analyses showed that miR-302b-5p had good specificity and sensitivity for distinguishing HCC tissue from non-cancerous liver tissue. Bioinformatics analyses identified 227 putative genes, and these genes were evidently enriched in the processes of organelle fission, chromosome and chromatin binding and were centralized in a "lysosome" pathway. The PPI network indicated that DNA topoisomerase II alpha (TOP2 A) was the most prominent hub gene of miR-302b-5p in HCC. Interestingly, according to the TCGA and Genotype-Tissue Expression databases, the mRNA and protein expression of TOP2 A were both elevated in HCC tissue samples as compared to non-cancerous liver tissue samples, and the overall survival and disease-free survival revealed that a high level of TOP2 A might reflect poor HCC outcome. CONCLUSIONS: Our findings indicate that miR-302b-5p might suppress HCC progression, and TOP2 A might be a potential target of miR-302b-5p in HCC. However, in-depth in vivo and in vitro experiments are required to verify these findings and explore the mechanisms involved.

Overexpression of MiR-452-5p in hepatocellular carcinoma tissues and its prospective signaling pathways.

BACKGROUND: The implication of miR-452-5p and its prospective machinery in hepatocellular carcinoma (HCC) remains largely unknown. For this reason, this study aimed to inspect the clinical implication of miR-452-5p expression in HCC tissues with multiple detection approaches, to analyze its potential function via in silico methods, and to validate this using a dual-luciferase reporter assay. METHODS: The assessment of the expression level of miR-452-5p in HCC was conducted via four methods: 1) in-house real-time quantitative PCR (RT-qPCR), 2) miRNA-sequencing (miRNA-seq) from The Cancer Genome Atlas (TCGA), 3) miRNA microarrays from the Gene Expression Omnibus (GEO), and 4) comprehensive meta-analyses calculating the standard mean difference (SMD) and summary of receiver operator characteristic (sROC). Following the target prediction, one of the potential targets of miR-452-5p was validated through a dual-luciferase reporter assay. RESULTS: MiR-452-5p was consistently elevated in HCC tissues via various detection methods, including in-house RT-qPCR, miRNA-seq, and miRNA microarrays. The final SMD was 0.842 for 820 cases of HCC samples. Simultaneously, the area under curve (AUC) of the sROC was 0.80 (0.76-0.83). The 1,135 predicted targets of miR-452-5p were enriched in the pathways of cytokine-cytokine receptor interaction, carbon metabolism, and complement and coagulation cascades. Among these predicted targets, CDKN1B was verified to be a real target of miR-452-5p. CONCLUSION: The overexpression of miR-452-5p may play a pivotal role in the carcinogenesis of HCC via targeting multiple signaling pathways and genes. The function and molecular machinery of miR-452-5p in HCC requires further in-depth exploration.

Exploration and validation of downregulated microRNA-199a-3p, downstream messenger RNA targets and transcriptional regulation in osteosarcoma.

Osteosarcoma (OS) is a primary bone tumor with a high incidence and mortality in children and adolescents. Emerging evidence shows that microRNAs (miRNAs) participate in biological tumor mechanisms by targeting downstream messenger RNAs (mRNAs). This article aimed to investigate the potential regulatory targets of microRNA-199a-3p (miR-199a-3p) in OS and to contribute to the understanding of miR-199a-3p-related OS regulatory mechanisms. MicroRNA-related Gene Expression Omnibus (GEO) chips, ArrayExpress chips and literature data were used to determine the expression of miR-199a-3p in OS and pooled to explore its potential clinical value. To investigate the target genes of miR-199a-3p further, we integrated the results from the following three-part gene study: Twelve online prediction tools were used to predict the target genes of miR-199a-3p; the GEO GSE89370 chip transfected with miRSelect pEP-miR-199a-3p was used to analyze the downregulated differentially expressed genes (DEGs) in OS cells; and highly expressed DEGs were derived from an in-house microarray generated from three pairs of clinical OS and normal tissue samples acquired through our department. Then, we analyzed the target genes using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases and the protein-protein interaction (PPI) network to further identify the primary target genes. In addition, we constructed transcription factor (TF)-miRNA-joint gene feed-forward regulatory loops (FFLs) with Circuits DB using miR-199a-3p as the core. A comprehensive meta-analysis of a hub of miR-199a-3p targeted genes was performed to integrate expression level, summary ROC (sROC) curves and survival analysis results from the GEO data for verification and exploration. Finally, the expression levels of the hub genes were verified in OS tissues and U2OS cells by immunohistochemistry (IHC) and immunocytochemistry (ICC). Data on miR-199a-3p expression were obtained from three data sets (GSE65071, GSE69524, and PMID 21666078), which showed low miR-199a-3p expression levels in OS tissues. The combined data indicated the same tendency, with the SMD of the random effect model, as shown in forest plots, being -2.8 (95% CI: -4.49, -1.11). In addition, we determined that miR-199a-3p may serve as a molecular marker useful for distinguishing OS tissues from normal tissues with high sensitivity and specificity, with the measured outcomes being 0.94 (95% CI: 0.80, 0.99) and 0.96 (95% CI: 0.78, 1.00), respectively. In addition, 391 genes were considered targets of miR-199a-3p in OS, and the enrichment analysis indicated that these targets were mainly enriched in proteoglycans in cancer and in spliceosomes. Four genes, CDKI, CCNB1, AURKA and NEK2, were regarded as hub targets based on the PPI data. Subsequently, TF-miRNA-joint genes FFLs were constructed in Circuits DB and included 17 TFs and 82 joint targets. These joint targets were mainly enriched in spliceosomes. UBE2D1 and RBM25 were regarded as hub joint targets based on the enrichment analysis. All selected target genes were further verified to ensure that they were upregulated in OS and to determine their prognostic significance. At the experimental verification level, the CDK1 protein was confirmed to be positively expressed in the cytoplasm of OS tissues and the U2OS cell line. Our study verified that miR-199a-3p was obviously downregulated in OS. CDK1, CCNB1, NEK2, AURKA, UBE2D1 and RBM25 were identified as potential target genes of miR-199a-3p in OS.

Expression and potential molecular mechanisms of miR­204­5p in breast cancer, based on bioinformatics and a meta­analysis of 2,306 cases.

Breast cancer (BC) is the most common cancer among women worldwide. However, there is insufficient research that focuses on the expression and molecular mechanisms of microRNA (miR)­204­5p in BC. In the current study, data were downloaded from the Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO) and the University of California Santa Cruz (UCSC) Xena databases. They were then used to undertake a meta­analysis that leveraged the standard mean difference (SMD) and summarized receiver operating characteristic (sROC) to evaluate the expression of the precursor miR­204 and mature miR­204­5p in BC. Additionally, an intersection of predicted genes, differentially expressed genes (DEGs) from the TCGA database and the GEO database were plotted to acquire desirable putative genes. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and protein­protein interaction (PPI) network analyses were performed to assess the potential pathways and hub genes of miR­204­5p in BC. A decreased trend in precursor miR­204 expression was detected in 1,077 BC tissue samples in comparison to 104 para­carcinoma tissue samples in the TCGA database. Further, the expression of mature miR­204­5p was markedly downregulated in 756 BC tissue samples in comparison to 76 para­carcinoma tissue samples in the UCSC Xena database. The outcome of the SMD from meta­analysis also indicated that the expression of miR­204­5p was markedly reduced in 2,306 BC tissue samples in comparison to 367 para­carcinoma tissue samples. Additionally, the ROC and sROC values indicated that miR­204­5p had a great discriminatory capacity for BC. In GO analysis, 'cell development', 'cell surface activity', and 'receptor agonist activity' were the most enriched terms; in KEGG analysis, 'endocytosis' was significantly enriched. Rac GTPase activating protein 1 (RACGAP1) was considered the hub gene in the PPI network. In conclusion, miR­204­5p may serve a suppressor role in the oncogenesis and advancement of BC, and miR­204­5p may have crucial functions in BC by targeting RACGAP1.

Upregulated miR­203a­3p and its potential molecular mechanism in breast cancer: A study based on bioinformatics analyses and a comprehensive meta­analysis.

Breast cancer (BC) has been identified as the leading malignancy in women worldwide. However, the potential molecular mechanism of microRNA (miR)­203a­3p in BC remains to be elucidated. The present study evaluated the expression of miR­203a­3p in BC and adjacent normal tissue in several publically available datasets. The distinguishability of precursor miR­203a and miR­203a­3p in BC tissue and adjacent breast tissue was assessed using receiver operating characteristic (ROC) and summarized ROC (sROC) approaches. In addition, gene ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes pathway analysis and protein­protein interaction analysis were performed to determine the potential molecular mechanism of miR­203a­3p in BC. It was identified that the expression of precursor miR­203a was markedly upregulated in 1,077 BC tissue samples compared to 104 adjacent breast tissue samples from The Cancer Genome Atlas. Additionally, an increasing trend in miR­203a­3p expression was observed in 756 BC tissue samples compared with 76 adjacent breast tissue samples from the University of California Santa Cruz Xena project. In addition, a comprehensive meta­analysis suggested that the expression of miR­203a­3p was markedly increased in 2,444 BC tissue samples compared with 559 adjacent breast tissue samples. The area under the curve of the ROC and sROC revealed that miR­203a­3p expression was able to distinguish between BC tissue and adjacent breast tissue. However, miR­203a­3p exhibited no prognostic value in BC. The results of GO enrichment demonstrated that the miR­203a target genes were associated with 'plasma membrane integrity', 'cell surface receptor linked signal and transduction' and '3',5'­cyclic nucleotide phosphodiesterase activity'. 'Purine metabolism' was identified as the pathway with the most enrichment of miR­203a­3p target genes in BC. The present study also identified insulin­like growth factor receptor (IGF1) as a hub gene associated with miR­203a in BC. In summary, miR­203a­3p may enhance the development and oncogenesis of BC, and IGF1 was defined as a hub gene of miR­203a­3p in BC.

Long non­coding RNA HOTTIP promotes hepatocellular carcinoma tumorigenesis and development: A comprehensive investigation based on bioinformatics, qRT­PCR and meta­analysis of 393 cases.

HOTTIP functions as an independent biomarker in multiple cancers. However, the role of HOTTIP in hepatocellular carcinoma (HCC) remains unclear. In this study, we sought to investigate the HOTTIP expression in HCC and normal liver. We combined quantitative reverse transcription-polymerase chain reactions (qRT­PCR), Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA), Multi Experiment Matrix (MEM) and Oncomine database to assess the clinical role and the potential molecular mechanism of HOTTIP in HCC. Furthermore, a meta­analysis was performed to evaluate the relationship between HOTTIP and HCC tumorigenesis and development. Additionally, bioinformatics analysis, which contained Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and network analysis, were applied to investigate the underlying functions, pathways and networks of the potential genes. HOTTIP was obviously upregulated in HCC. A statistically significant higher expression of HOTTIP was found in TNM (III +Ⅳ), age (≥60), sex (male), race (white) and cirrhosis (no) compared to the control groups (P<0.05). Furthermore, the meta­analysis of 393 cases from multiple centers indicated that HOTTIP had high diagnostic value in HCC. Additionally, according to GO and KEGG analyses, we found that the most strongly enriched functional terms were gland development, transcription factor activity and extrinsic to membrane. Also, the HOTTIP co­expressed genes were significantly related to PPAR signaling pathway. We speculate that HOTTIP might play a vital part in HCC via regulating various pathways, especially PPAR signaling pathway. However, the detailed mechanism should be confirmed by functional experiments.

Clinical Significance and Effect of lncRNA HOXA11-AS in NSCLC: A Study Based on Bioinformatics, In Vitro and in Vivo Verification.

HOXA11 antisense RNA (HOXA11-AS) has been shown to be involved in tumorigenesis and development of different cancers. However, the role of HOXA11-AS in non-small cell lung cancer (NSCLC) remains unclear. In this study, we firstly explored and confirmed the expression of HOXA11-AS in NSCLC tissues and cells. Cytometry, CCK-8, cell scratch, migration, Matrigel invasion and flow cytometry assays were performed to determine the biological impact of HOXA11-AS in vitro. Furthermore, a chick embryo chorioallantoic membrane (CAM) model of NSCLC was constructed to explore the effect of HOXA11-AS on tumorigenicity and angiogenesis in vivo. Additionally, bioinformatics analyses were performed to investigate the prospective pathways of HOXA11-AS co-expressed genes. As results, HOXA11-AS was markedly highly expressed in NSCLC tissues and cells. Furthermore, the proliferation, migration, invasion, tumorigenic and angiogenic ability of NSCLC cells were all inhibited and apoptosis was induced after HOXA11-AS knock-down. HOXA11-AS RNAi also led to cell cycle arrest on G0/G1 or G2/M phase. In addition, the non-small cell lung cancer pathway might be involved in regulating the co-expressed genes of HOXA11-AS in NSCLC. These results indicate that HOXA11-AS plays pivotal roles in NSCLC and it can become a novel therapeutic direction for treating NSCLC.