The lncRNA MALAT1 functions as a competing endogenous RNA to regulate MCL-1 expression by sponging miR-363-3p in gallbladder cancer.

Gallbladder carcinoma (GBC) is an aggressive neoplasm, and the treatment options for advanced GBC are limited. Recently, long non-coding RNAs (lncRNAs) have emerged as new gene regulators and prognostic markers in several cancers. In this study, we found that metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) expression was up-regulated in GBC tissues (P < 0.05). Luciferase reporter assays and RNA pull down assays showed that MALAT1 is a target of miR-363-3p. Real-time quantitative PCR and Western blot analysis indicated that MALAT1 regulated Myeloid cell leukaemia-1 (MCL-1) expression as a competing endogenous RNA (ceRNA) for miR-363-3p in GBC cells. Furthermore, MALAT1 silencing decreased GBC cell proliferation and the S phase cell population and induced apoptosis in vitro. In vivo, tumour volumes were significantly decreased in the MALAT1 silencing group compared with those in the control group. These data demonstrated that the MALAT1/miR-363-3p/MCL-1 regulatory pathway controls the progression of GBC. Inhibition of MALAT1 expression may be to a novel therapeutic strategy for gallbladder cancer.

Overexpression of LncRNA-ROR predicts a poor outcome in gallbladder cancer patients and promotes the tumor cells proliferation, migration, and invasion.

LncRNA-ROR has been reported to be involved in many kinds of human cancers. However, whether LncRNA-ROR is involved in gallbladder cancer progression remains largely unknown. The objective of this study is to investigate the role of LncRNA-ROR in gallbladder cancer. We found that LncRNA-ROR expression level was upregulated in gallbladder cancer tissues (P < 0.05) and was significantly associated with tumor sizes (P < 0.05) and lymph node metastasis (P < 0.05). High expression of LncRNA-ROR was significantly associated with poor prognosis in gallbladder cancer patients (P < 0.05). Moreover, knockdown of LncRNA-ROR inhibited cell proliferation, migration, and invasion. The epithelial-mesenchymal transition (EMT) phenotype induced by TGF-ß1 was reversed after LncRNA-ROR knocking down in SGC-996 and Noz cells. LncRNA-ROR plays an important role in the development of gallbladder cancer and mediates the EMT in gallbladder cancer. LncRNA-ROR might act as a marker of prognosis and therapeutic target for gallbladder cancer.

Long noncoding RNA H19 contributes to gallbladder cancer cell proliferation by modulated miR-194-5p targeting AKT2.

Gallbladder cancer (GBC) is a highly malignant cancer with poor prognosis. Although long noncoding RNA (lncRNA) H19 has been reported to play vital role in many human cancers, whether it is involved in GBC proliferation is still unknown. This study was designed to explore the effect of H19 in GBC cell proliferation. The expression of H19 and AKT2 were significantly elevated in GBC tissues, and the level of miR-194-5p is markedly decreased. Moreover, the RNA levels of H19 and AKT2 were positively correlated, and H19 elevation was significantly associated with tumor size. Cell proliferation decreased significantly after knockdown of H19 in GBC-SD and NOZ cells and after knockdown of AKT2 in NOZ cells. Results from cell cycle studies indicated that the S phase were significantly decreased after knockdown of H19 in NOZ cells but significantly elevated after overexpression of H19 in GBC-SD cells. Furthermore, knockdown of H19 upregulated miR-194-5p levels, yet significantly decreased miR-194-5p targeting AKT2 gene expression in NOZ cells. Inhibitor against miR-194-5p reversed these effects. In addition, overexpression of H19 in GBC-SD cells downregulated miR-194-5p and markedly increased AKT2 expression, and miR-194-5p mimic reversed these effects. Eventually, GBC cells were arrested in G0/G1-phase after H19 knockdown, inhibition of miR-194-5p markedly promoted cells into S-phase and co-transfection of siH19, and miR-194-5p inhibitor exerted mutually counter-regulated effects on cell cycle. These results suggested that H19/miR-194-5p/AKT2 axis regulatory network might modulate cell proliferation in GBC.

Near-Infrared Polymer Dots in the Portal-Hepatic Circulation Achieve Localization of Hepatic Carcinoma In Vivo.

The present study aims to use polymer dots to explore whether they can visualize tumor lesions in a diethylnitrosamine (DENA)-induced hepatocellular carcinoma (HCC) model. The HCC rat model was set up, and serum liver function indexes and AFP were tested on days 0, 30, 60, and 90 of the modeling process. After characterization of the polymer dots, they were injected into the rats and mice. The liver, spleen, and kidney of rats and the gallbladder of mice were extracted to verify the metabolic pathways of the polymer dots and their capability of fluorescent localization of HCC and gallbladder by fluorescence imaging. Strong fluorescent emission from the liver appeared immediately and 15 min after the polymer dots were injected through the main portal veins and tail veins of the model rats, respectively. A satisfactory fluorescent imaging effect lasted up to 45 min. Polymer dots circulate through the bloodstream within intrahepatic vessels rather than intracellular areas and can be clearly visualized by using both the pCLE and IVIS spectrum imaging systems. Contrast imaging of HCC lesions without fluorescent emissions was due to the lack of normal portal-hepatic veins within the tumor areas. Fluorescent imaging of the gallbladder could also be detected at 15 min after the polymer dots were injected through the tail veins of mice. The polymer dots had satisfactory fluorescent localization capability for targeted intrahepatic vessels and HCC lesions in vivo and showed potential practical value in hepato-biliary surgery.

Long non-coding RNA TUG1 promotes cell proliferation and metastasis by negatively regulating miR-300 in gallbladder carcinoma.

BACKGROUND: As we all know, long non-coding RNAs (lncRNAs) have been reported to play vital roles in various human cancers. In this study, we aimed to explore the role of lncRNA TUG1 in gallbladder carcinoma (GBC) development. METHODS: Total RNA was extracted from the tissues of thirty GBC patients, four GBC cell lines. We detected the expression levels of TUG1 using quantitative real-time PCR. We performed CCK8, colony formation, transwell invasion and apoptosis assays to study the effects of TUG1 on GBC cell proliferation and invasion. Western blot assay was performed to assess to the expression level of epithelial-mesenchymal transition (EMT) markers in transforming growth factor-ß1 (TGF-ß1) treated and TUG1 knockdown GBC cell. Lastly, dual-luciferase reporter assay and quantitative real-time PCR were performed to verify the potential target microRNAs (miRNAs) of TUG1. RESULTS: TUG1 expression was significantly overexpressed in GBC tissues. Functionally, this study demonstrated that knockdown of TUG1 significantly inhibited GBC cell proliferation, metastasis. Mechanically, we found that TUG1 is upregulated by TGF-ß1, and knockdown of TUG1 inhibited GBC cell EMT. Furthermore, we identified that miR-300, which has been reported as a suppressor in other types of cancer, is negatively regulated by TUG1. CONCLUSIONS: LncRNA TUG1 promotes GBC cell proliferation, metastasis and EMT progression by functioning as a miRNA sponge to abrogate the endogenous effect of miR-300.

The NmrA-like family domain containing 1 pseudogene Loc344887 is amplified in gallbladder cancer and promotes epithelial-mesenchymal transition.

The expression pattern and biological role of long non-coding RNA (lncRNA) in cancer has been reported to be involved in many cancers. Here, we report the expression and biological role of a newly discovered lncRNA NmrA-like family domain containing 1 pseudogene (Loc344887) in gallbladder cancer (GBC). In this study, we found that the expression of Loc344887 was significantly elevated in GBC tissues and cell lines when compared with matched normal tissues and normal epithelial bile duct cell line, respectively. High Loc344887 was associated with larger tumor size. Loc344887 was upregulated significantly after ectopic expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in GBC cells. Downregulation of Loc344887 in GBC cells suppressed cell proliferation, blocked cells in G0/S phase, and decreased the migration and invasion cell numbers. In addition, downregulation of Loc344887 decreased the expression of transcription factor Twist, mesenchymal marker Vimentin, and N-cadherin and increased the expression of epithelial maker E-cadherin, which could prompt a mesenchymal-to-epithelial transition phenotype. These results demonstrated that Loc344887 might contribute to cell proliferation and epithelial-to-mesenchymal transition process in GBC, which might be a potential therapeutic target.

Upregulation of H19 indicates a poor prognosis in gallbladder carcinoma and promotes epithelial-mesenchymal transition.

The imprinted oncofetal long non-coding RNA H19 has been reported to be involved in many kinds of human cancers. However, whether lncRNA H19 implicate in oncogenesis and cancer progression in gallbladder cancer remain largely unknown. In the present study, compared with adjacent normal tissues, the level of H19 was significantly upregulated in gallbladder cancer tissues and was positively associated with lymphatic metastasis and tumor size. The overall survival is shorter in those who had higher H19 expression among GBC patients. In vitro, both TGF-ß1 and IL-6 treatment induced upregulation of H19, downregulated the protein level of E-cadherin while increased Vimentin, indicating an epithelial-mesenchymal transition (EMT) phenotype in GBC. The overexpression of H19 in GBC cells enhanced tumor invasion and promoted EMT by upregulated transcription factor Twist1. On the contrary, Loss of function studies indicated that H19 interference in GBC suppressed tumor cell invasion and promoted mesenchymal-epithelial transition (MET) via suppressing Twist expression. In vivo, the volume of the tumors in H19-inteference group was significantly decreased compared to those in the control group of nude mice. Both western-blot and immunohistochemistry confirmed that a MET phenotype existed in the H19 interference group when compared to control group. These results defined H19 as a novel prognostic factor for GBC, and indicated that it might play important regulatory roles in the EMT process.

Erratum: Upregulation of H19 indicates a poor prognosis in gallbladder carcinoma and promotes epithelial-mesenchymal transition.

[This corrects the article on p. 15 in vol. 6, PMID: 27073719.].

Overexpression of LncRNA AFAP1-AS1 predicts poor prognosis and promotes cells proliferation and invasion in gallbladder cancer.

BACKGROUND: Long non-coding RNA actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1) has been elucidated to be associated with some kinds of human cancers. However, whether lncRNA AFAP1-AS1 implicates in tumor development of gallbladder cancer (GBC) remains largely unknown. This study aims to elucidate the tumorigenic role and regulatory function of lncRNA AFAP1-AS1 in gallbladder cancer. METHODS: We analyzed lncRNA AFAP1-AS1 expression by quantitative real time PCR (qRT-PCR) in 40 gallbladder cancer tissue and adjacent normal tissues, survival plots were generated by Kaplan-Meier analysis and the log-rank test. The expression levels of transcription factor Twist1 and epithelial-to mesenchymal transition (EMT) makers (E-cadherin and Vimentin) were detected by quantitative real time PCR and western blotting analysis after knockdown of lncRNA AFAP1-AS1. RESULTS: The expression levels of lncRNA AFAP1-AS1 were significantly elevated in GBC tissues and GBC cell lines. In addition, the expression level of lncRNA AFAP1-AS1 was significantly associated with tumor sizes and the higher expression of lncRNA AFAP1-AS1 was correlated with poor prognosis in GBC patients. Knockdown of LncRNA AFAP1-AS1 suppressed cell growth and invasion in NOZ and GBC-SD cells. Furthermore, we found that knockdown of LncRNA AFAP1-AS1 in GBC cells inhibited EMT by down-regulating the transcription factor Twist1 and Vimentin and up-regulated the E-cadherin. CONCLUSIONS: Our results suggested lncRNA AFAP1-AS1 was correlated with poor prognosis in GBC patients and lncRNA AFAP1-AS1 might be novel therapeutic target in gallbladder cancer.

Upregulation of long non-coding RNA LINC00152 by SP1 contributes to gallbladder cancer cell growth and tumor metastasis via PI3K/AKT pathway.

Gallbladder cancer (GBC) is one of the most lethal cancers with poor prognosis. In this study, we report that the long non-coding RNA LINC00152 is significantly upregulated in GBC tissues and cell lines. The high LINC00152 levels correlated positively with tumor status progression, lymph node invasion and TNM stage advancement. Functionally, we revealed that LINC00152 dramatically promoted cell proliferation, metastasis and inhibited apoptosis in vitro. In vivo, LINC00152 overexpression significantly promoted tumor growth. Mechanistic analyses indicated that LINC00152 could participate in the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, and transcription factor specificity protein 1 (SP1) induces its overexpression. In summary, our findings suggest that LINC00152 contributes to the oncogenic potential of GBC and SP1/LINC00152/PI3K/AKT may be a potential therapeutic target for GBC.

Long non-coding RNA MINCR promotes gallbladder cancer progression through stimulating EZH2 expression.

The regulation of MYC-regulated long non-coding RNAs has been reported to contribute to certain types of cancers. However, the role of MYC-induced long non-coding RNA (MINCR) in the tumorigenesis of gallbladder cancer (GBC) is still largely unknown. In this study, we discovered that MINCR was markedly upregulated in GBC tissues compared with adjacent normal tissues. High MINCR expression levels in GBC were positively associated with tumor volume and lymph node metastasis and were negatively correlated with overall survival (OS). Upregulation of MINCR and enhancer of zeste homolog 2 (EZH2) in GBC coincided with the downregulation of miR-26a-5p in GBC. Mechanistically, MINCR/miR-26a-5p/EZH2 axis was found to be involved in cell proliferation, cell invasive and apoptosis in GBC cells. Moreover, knockdown of MINCR suppressed cell proliferation, decreased S-phase cell numbers, increased cell apoptosis, and inhibited cell invasion by inhibiting the epithelial-mesenchymal transition (EMT) phenomenon in GBC cells. In vivo, tumor volumes were significantly decreased in the MINCR silencing group compared with those in the control group. These results demonstrated that MINCR could potentially be a therapeutic target as well as a prognostic marker in GBC.

Long non-coding RNA Malat1 promotes gallbladder cancer development by acting as a molecular sponge to regulate miR-206.

Long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (Malat1) functions as an oncogene in many types of human cancer. In this study, we show that Malat1 is overexpressed in gallbladder cancer (GBC) tissue and cells. The high Malat1 levels correlated positively with tumor size and lymphatic metastasis, and correlated negatively with overall survival. We also show that Malat1 functions as a competing endogenous RNA (ceRNA) for miR-206. Because miR-206 directly suppresses expression of ANXA2 and KRAS, which are thought to promote GBC progression, Malat1 binding of miR-206 in GBC tissue and cells has an oncogenic effect. Conversely, Malat1 knockdown inhibits proliferation and invasion by GBC cells while increasing apoptosis. In vivo, silencing Malat1 decreases tumor volume. These results suggest Malat1 could potentially serve as a therapeutic target and prognostic marker for GBC.

Long non-coding RNA H19 regulates FOXM1 expression by competitively binding endogenous miR-342-3p in gallbladder cancer.

BACKGROUND: Long non-coding RNA (lncRNA) H19 has been reported to involve in many kinds of human cancers and functions as an oncogene. Our previous study found that H19 was over-expressed in gallbladder cancer (GBC) and was shown to promote tumor development in GBC. However, the competing endogenous RNA (ceRNA) regulatory network involving H19 in GBC progression has not been fully elucidated. We aim to detect the role of H19 as a ceRNA in GBC. METHODS AND RESULTS: In this study, the expression of H19 and miR-342-3p were analyzed in 35 GBC tissues and matched normal tissues by using quantitative polymerase chain reaction (qRT-PCR). We demonstrated H19 was overexpressed and negatively correlated with miR-342-3p in GBC. By dual-luciferase reporter assays, RNA-binding protein immunoprecipitation (RIP) and RNA pull-down assays, we verified that H19 was identified as a direct target of miR-342-3p. QRT-PCR and Western-blotting assays demonstrated that H19 silencing down-regulated, whereas over-expression enhanced the expression of miR-342-3p targeting FOXM1 through competitively 'sponging' miR-342-3p. Furthermore, transwell invasion assays and cell cycle assays indicated that H19 knockdown inhibited both cells invasion and proliferation, but this effects was attenuated by co-transfection of siRNA-H19 and miR-342-3p inhibitor in GBC cells. In vivo, tumor volumes were decreased significantly in H19 silenced group compared to the control group, but was attenuated by co-transfection of shRNA-H19 and miR-342-3p inhibitor, which were stablely constructed through lenti-virus vector. CONCLUSION: Our results suggest a potential ceRNA regulatory network involving H19 regulates FOXM1 expression by competitively binding endogenous miR-342-3p in GBC. This mechanism may contribute to a better understanding of GBC pathogenesis and provides potential therapeutic strategy for GBC.

Long Noncoding RNA GCASPC, a Target of miR-17-3p, Negatively Regulates Pyruvate Carboxylase-Dependent Cell Proliferation in Gallbladder Cancer.

Long noncoding RNAs (lncRNA) are being implicated in the development of many cancers. Here, we report the discovery of a critical role for the lncRNA GCASPC in determining the progression of gallbladder cancer. Differentially expressed lncRNAs and mRNAs between gallbladder cancer specimens and paired adjacent nontumor tissues from five patients were identified and validated by an expression microarray analysis. Quantitative real-time PCR was used to measure GCASPC levels in tissues from 42 gallbladder cancer patients, and levels of GCASPC were confirmed further in a separate cohort of 89 gallbladder cancer patients. GCASPC was overexpressed or silenced in several gallbladder cancer cell lines where molecular and biological analyses were performed. GCASPC levels were significantly lower in gallbladder cancer than adjacent nontumor tissues and were associated with tumor size, American Joint Committee on Cancer tumor stage, and patient outcomes. GCASPC overexpression suppressed cell proliferation in vitro and in vivo, whereas GCASPC silencing had opposite effects. By RNA pull-down and mass spectrometry, we identified pyruvate carboxylase as an RNA-binding protein that associated with GCASPC. Because GCASPC is a target of miR-17-3p, we confirmed that both miR-17-3p and GCASPC downregulated pyruvate carboxylase level and activity by limiting protein stability. Taken together, our results defined a novel mechanism of lncRNA-regulated cell proliferation in gallbladder cancer, illuminating a new basis for understanding its pathogenicity. Cancer Res; 76(18); 5361-71. ©2016 AACR.