Linc00210 drives Wnt/ß-catenin signaling activation and liver tumor progression through CTNNBIP1-dependent manner.

BACKGROUND: Liver tumor initiating cells (TICs) have self-renewal and differentiation properties, accounting for tumor initiation, metastasis and drug resistance. Long noncoding RNAs are involved in many physiological and pathological processes, including tumorigenesis. DNA copy number alterations (CNA) participate in tumor formation and progression, while the CNA of lncRNAs and their roles are largely unknown. METHODS: LncRNA CNA was determined by microarray analyses, realtime PCR and DNA FISH. Liver TICs were enriched by surface marker CD133 and oncosphere formation. TIC self-renewal was analyzed by oncosphere formation, tumor initiation and propagation. CRISPRi and ASO were used for lncRNA loss of function. RNA pulldown, western blot and double FISH were used to identify the interaction between lncRNA and CTNNBIP1. RESULTS: Using transcriptome microarray analysis, we identified a frequently amplified long noncoding RNA in liver cancer termed linc00210, which was highly expressed in liver cancer and liver TICs. Linc00210 copy number gain is associated with its high expression in liver cancer and liver TICs. Linc00210 promoted self-renewal and tumor initiating capacity of liver TICs through Wnt/ß-catenin signaling. Linc00210 interacted with CTNNBIP1 and blocked its inhibitory role in Wnt/ß-catenin activation. Linc00210 silencing cells showed enhanced interaction of ß-catenin and CTNNBIP1, and impaired interaction of ß-catenin and TCF/LEF components. We also confirmed linc00210 copy number gain using primary hepatocellular carcinoma (HCC) samples, and found the correlation between linc00210 CNA and Wnt/ß-catenin activation. Of interest, linc00210, CTNNBIP1 and Wnt/ß-catenin signaling targeting can efficiently inhibit tumor growth and progression, and liver TIC propagation. CONCLUSION: With copy-number gain in liver TICs, linc00210 is highly expressed along with liver tumorigenesis. Linc00210 drives the self-renewal and propagation of liver TICs through activating Wnt/ß-catenin signaling. Linc00210 interacts with CTNNBIP1 and blocks the combination between CTNNBIP1 and ß-catenin, driving the activation of Wnt/ß-catenin signaling. Linc00210-CTNNBIP1-Wnt/ß-catenin axis can be targeted for liver TIC elimination.

LncAPC drives Wnt/ß-catenin activation and liver TIC self-renewal through EZH2 mediated APC transcriptional inhibition.

Liver tumor initiating cells (TICs), a small subset cells in tumor bulk, are responsible for liver tumor initiation, metastasis, and relapse. However, the regulatory mechanism of liver TICs remains largely unknown. Here we found a long noncoding RNA lncAPC, locating near from APC locus, was highly expressed in liver cancer and liver TICs. LncAPC was required for liver TIC self-renewal. Silencing and overexpressing lncAPC showed impaired and enhanced sphere formation capacity of liver TICs, respectively. By recruiting EZH2 to APC promoter, LncAPC inhibits APC transcription and thus drives the activation of Wnt/ß-catenin signaling. Attenuate binding between EZH2 and APC promoter was observed upon lncAPC knockdown. What is more, lncAPC-EZH2-APC axis can be targeted to eliminate liver TICs. Altogether, LncAPC promotes liver TIC self-renewal through EZH2-dependent APC transcriptional inhibition.

Plasma BNP level combined with surgical Apgar score to predict operative major cardiac adverse events in malignant obstructive jaundice patients.

OBJECTIVE: To investigate the predictive effect of major adverse cardiac events (MACE) in malignant obstructive jaundice (OJ) patients using plasma brain natriuretic peptide (BNP) level and surgical Apgar scoring (SAS) system. METHODS: Forty one malignant OJ patients undergoing surgical treatments were studied at a single center. Pre-and postoperative plasma BNP level, total bilirubin (TBil) and data of cardiac function (HR, CVP, CI, LVEF%) were detected, the SAS was calculated during the surgery, the relationship of both plasma BNP level and SAS with MACE after surgery was analyzed. RESULTS: Thirteen patients out of 41 (31.71%) experienced MACE without cardiac death. OJ patients had a higher plasma BNP level than baseline before operation (191.61±105.76 pg/ml VS 175 pg/ml, P<0.05), the cardiac function data was improved (CVP: t=4.761, p=0.000; CI: t=3.539, p=0.001; LVEF%: t=3.632, p=0.001) after the operation. Patients with lower SAS had increasing incidence of MACE after surgery. CONCLUSION: Malignant OJ patients with higher preoperative BNP level and lower surgical Apgar score were identified at high risk of MACE after surgery.

MEF2 transcription factors promotes EMT and invasiveness of hepatocellular carcinoma through TGF-ß1 autoregulation circuitry.

Invasion and metastasis is the main causes leading to the death of hepatocellular carcinoma (HCC) patients. However, the underlying mechanism is still to be explored. Transforming growth factor ß1 (TGF-ß1) is a stronger inducer of HCC cell invasion. However, the downstream effector of TGF-ß1 that promotes HCC invasion is still unknown. In this study, we found that PI3K/Akt activation takes place following the stimulation of TGF-ß1. The inhibition of PI3K/Akt activation abolished epithelial-mesenchymal transition (EMT) and invasion of HCC cells induced by TGF-ß1. Myocyte enhancer factors 2 (MEF2) family proteins were found to be overexpressed in HCC cells under the treatment of TGF-ß1 in a PI3K/Akt-dependent way. Silencing the expression of MEF2s was able to prevent the effect of TGF-ß1 on HCC EMT and invasion. Unexpectedly, MEF2 proteins were able to promote the expression of TGF-ß1 in HCC cells, suggesting the existence of regulatory circuitry consisting of TGF-ß1, PI3K/Akt, and MEF2. A natural compound, oleanolic acid, was demonstrated to suppress the invasion and EMT of HCC cells by downregulating MEF2, showing that targeting this pathway is an effective therapeutic strategy for HCC invasion. We believe that our findings can contribute to better understanding of the involved mechanism of HCC invasion and the development of preventive and therapeutic strategy.

CircANTXR1 Contributes to the Malignant Progression of Hepatocellular Carcinoma by Promoting Proliferation and Metastasis.

BACKGROUND: Circular RNA (circRNA) is a key regulator for the malignant progression of cancer. However, the role of circRNA anthrax toxin receptor 1 (circANTXR1) in hepatocellular carcinoma (HCC) is still unclear. METHODS: Quantitative real-time PCR was performed to detect RNA expression. Cell proliferation, migration and invasion were determined using MTT assay, EdU staining, colony formation assay, wound healing assay and transwell assay. The protein levels of metastasis markers, x-ray repair cross complementing 5 (XRCC5) and exosome markers were examined using Western blot analysis. Xenograft tumor models were built to investigate the role of circANTXR1 in HCC tumorigenesis. The relationship between microRNA (miR)-532-5p and circANTXR1 or XRCC5 was confirmed by dual-luciferase reporter assay and RNA pull-down assay. The identification of exosomes were performed using transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). RESULTS: CircANTXR1 was a stable and highly expressed circRNA in HCC. Silenced circANTXR1 inhibited the proliferation, migration and invasion of HCC cells in vitro, and suppressed HCC tumor growth in vivo. MiR-532-5p could be sponged by circANTXR1, and its inhibitor could reverse the inhibition of circANTXR1 silencing on HCC cells progression. In addition, we discovered that XRCC5 was a target of miR-532-5p. Furthermore, XRCC5 overexpression could reverse the suppressive effect of miR-532-5p overexpression on HCC cell proliferation, migration and invasion. Exosome was involved in the transport of circANTXR1 in HCC cells. Exosome circANTXR1 might be a potential serum biomarker for HCC patients. CONCLUSION: CircANTXR1 promotes the progression of HCC through the miR-532-5p/XRCC5 axis, which might be a potential serum biomarker and therapeutic target of HCC.

Several genes involved in the JAK-STAT pathway may act as prognostic markers in pancreatic cancer identified by microarray data analysis.

PURPOSE: This study aimed to identify the underlying mechanisms in pancreatic cancer (PC) carcinogenesis and those as potential prognostic biomarkers, which can also be served as new therapeutic targets of PC. METHODS: Differentially expressed genes (DEGs) were identified between PC tumor tissues and adjacent normal tissue samples from a public GSE62452 dataset, followed by functional and pathway enrichment analysis. Then, protein-protein interaction (PPI) network was constructed and prognosis-related genes were screened based on genes in the PPI network, before which prognostic gene-related miRNA regulatory network was constructed. Functions of the prognostic gene in the network were enriched before which Kaplan-Meier plots were calculated for significant genes. Moreover, we predicted related drug molecules based on target genes in the miRNA regulatory network. Furthermore, another independent GSE60979 dataset was downloaded to validate the potentially significant genes. RESULTS: In the GSE62452 dataset, 1017 significant DEGs were identified. Twenty-six important prognostic-related genes were found using multivariate Cox regression analysis. Through pathway enrichment analysis and miRNA regulatory analysis, we found that the 5 genes, such as Interleukin 22 Receptor Subunit Alpha 1 (IL22RA1), BCL2 Like 1 (BCL2L1), STAT1, MYC Proto-Oncogene (MYC), and Signal Transducer And Activator Of Transcription 2 (STAT2), involved in the Jak-STAT signaling pathway were significantly associated with prognosis. Moreover, the expression change of these 5 genes was further validated using another microarray dataset. Additionally, we identified camptothecin as an effective drug for PC. CONCLUSION: IL22RA1, BCL2L1, STAT1, MYC, and STAT2 involved in the Jak-STAT signaling pathway may be significantly associated with prognosis of PC.

MicroRNA-200c overexpression inhibits chemoresistance, invasion and colony formation of human pancreatic cancer stem cells.

INTRODUCTION: Cancer stem cells (CSCs) are believed to be 'seed cell' in cancer recurrence and metastasis. MicroRNAs (miRNAs) have emerged as potential therapeutic candidates due to their ability to regulate multiple targets involved in tumor progression and chemoresistance. The goal of this study was to investigate the role of miRNA-200c (miR-200c) in regulating colony formation, invasion and chemoresistance of human pancreatic cancer stem cells (PCSCs). METHODS: PCSCs with CD24(+)CD44(+)ESA(+) as the marker was sorted from PANC-1 cell line by fluorescence activated cell sorter (FACS). Quantitative real-time PCR (qRT-PCR) assay was used to detect the expression of miR-200c in PCSCs and PANC-1 cells. Transfection of miR-200c mimic into PCSCs was performed to establish miR-200c over-expressed cells. The effects of overexpressing miR-200c on PCSCs were examined by cell colony forming, invasion and survival assays in vitro. RESULTS: Our data showed that CD24(+)CD44(+)ESA(+) PCSCs (0.5%) were isolated from PANC-1 cells. Expression of miR-200c was significantly reduced in PCSCs compared with PANC-1 cells. In addition, the capability of colony formation, invasion and chemoresistance were markedly increased in PCSCs than that in PANC-1 cells. Adverse results were obtained in miR-200c overexpressing PCSCs transfected with miR-200c mimic. CONCLUSION: Our study demonstrated that miR-200c overexpression could decrease colony formation, invasion and chemoresistance of PCSCs. It may become a new therapeutic target for gene therapy in patients suffered from pancreatic cancer.

Expression of long non-coding RNA LOC285194 and its prognostic significance in human pancreatic ductal adenocarcinoma.

INTRODUCTION: Dysregulation of long non-coding RNAs (lncRNAs) plays critical roles in tumor progression. lncRNA LOC285194 was previously shown to be correlated with aggressive clinicopathological features and poor prognosis in several cancers. The aim of this study was to investigate relationship between LOC285194 expression and clinical outcomes in human pancreatic ductal adenocarcinoma (PDAC). METHODS: Quantitative real-time PCR (qRT-PCR) assay was performed to detect the expression of lncRNA LOC285194 in human PDAC cells and tissue samples. The association of LOC285194 expression with clinicopathologic features was analyzed. Kaplan-Meier analyses were used to assess survival of patients. Univariate and multivariate analyses were performed using the Cox proportional hazards model to analyze the prognostic significance of LOC285194 expression. RESULTS: Our data showed that the relative level of LOC285194 in PDAC cells was significantly lower than that in normal human pancreatic duct epithelial cell line. Also, the expression of LOC285194 in PDAC tissues was significantly lower than that in adjacent non-tumor tissues. By statistical analyses, low LOC285194 expression was observed to be closely correlated with clinical stage, lymphnode metastasis and liver metastasis. Kaplan-Meier survival analysis revealed that patients with low LOC285194 expression had a poor overall survival compared with the high LOC285194 group (P < 0.05). Univariate and multivariate analyses showed that low LOC285194 expression was an independent poor prognostic factor for PDAC patients. CONCLUSIONS: Our data provided the first evidence that reduced LOC285194 in PDAC tissues was correlated with tumor progression, and lncRNA LOC285194 might be a potential molecular biomarker for predicting the prognosis of patients.