LncRNA AY promotes hepatocellular carcinoma metastasis by stimulating ITGAV transcription.
ABSTRACT: Rationale: Tumor metastasis is the main cause for cancer-related death. However, the driving molecules of metastasis remain largely unknown. Here, we aim to identify long non-coding RNAs (lncRNAs) critical for human hepatocellular carcinoma (HCC) metastasis. Methods: Microarrays were used to screen a comprehensive set of lncRNAs with differential expression profiles in sulfatide-treated cells. Mass spectrometry, protein arrays, and RNA pull-down experiments were used to identify proteins that interacted with lncRNA. Epigenetic analysis was used to study lncRNA-mediated regulation mechanisms. Results: We identified lncRNA AY927503 (AY) as a metastasis-associated molecule that was highly expressed in human hepatocellular carcinoma (HCC) and correlated with metastatic events and poor prognosis in patients with HCC. AY promoted HCC cell migration, stemness, 5-fluorouracil resistance, and metastasis in mice. However, knockdown of integrin ?V (ITGAV) abolished AY-stimulated migration, cell viability in HCC cells or tube formation. AY strongly promoted ITGAV transcription and ?V?3 expression by interacting with the ITGAV promoter specifically and stimulating its activity. AY was identified to interact with histone 1FX (H1FX), but deletion of the central domain of AY (AY?371-522) abolished H1FX binding and ITGAV promoter stimulation. AY significantly enriched H3K4Me3 and acH3K9/14 but reduced H3K27Me3 and H1FX occupancy on the ITGAV promoter, which remodeled chromatin structures for RNA polymerase II recruitment. Knockdown of H1FX abrogated ITGAV transcription stimulated by AY. Conclusions: Our findings suggested that lncRNA AY promoted HCC metastasis via induction of chromatin modification for ITGAV transcription as a pioneer factor and was a potential molecular signature for metastasis or poor prognosis in patients with HCC.
Project description:During tumorigenesis and metastasis, integrins regulate localization and activity of proteolytic enzymes that remodel the extracellular matrix. Previous studies have demonstrated blocking of ?V?3 to effectively inhibit proliferation, angiogenesis, and the survival of various cancer cell types. However, little is known about the functional role of the integrin subunit alpha-V gene (ITGAV) in metastatic breast cancer. In this study, ITGAV knockdown was used to identify the molecular mechanism by which ITGAV promotes tumorigenesis, metastasis, proliferation, invasion, and cellular self-renewal. The effectiveness of an ITGAV antagonist, cilengitide, for breast cancer treatment was investigated in vivo. Analysis of publicly available data demonstrated that overexpression of ITGAV was associated with poor relapse free survival of breast cancer patients. Silencing of ITGAV inhibited cell proliferation, invasion, and self-renewal of breast cancer cell lines by altering expression of BCL2 and PXN. The use of cilengitide significantly reduced lung metastasis in a metastatic breast cancer animal model. In conclusion, overexpression of ITGAV contributes to breast cancer metastasis through upregulation of PXN. Targeting ITGAV is a potential treatment for metastatic breast cancer as well as primary breast tumors with high ITGAV expression. ITGAV expression levels may be useful predictors of patient treatment and outcome responses.
Project description:Hepatocellular carcinoma (HCC) is a highly aggressive, solid malignancy that has a poor prognosis. Long non-coding RNAs (lncRNAs) have been found to be dysregulated in various cancers, including HCC. However, the molecular mechanism involving lncRNAs in HCC remains largely unknown. In this study, lncRNAs differentially expressed between HCC and corresponding non-cancerous tissue were identified by microarray analysis. A specific differentially expressed lncRNA UBE2CP3 (ubiquitin conjugating enzyme E2 C pseudogene 3) was identified. LncRNA UBE2CP3 was frequently up-regulated in HCC samples as assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and in situ hybridization (ISH) experiments. Clinical data showed that high levels of lncRNA UBE2CP3 were correlated with poor prognosis in HCC patients. Functional studies demonstrated that over-expression of lncRNA UBE2CP3 promoted cell invasion and migration in vitro and in vivo. Mechanistically, enhanced expression of lncRNA UBE2CP3 increased the expression of Snail1 and N-cadherin, but decreased the expression of E-cadherin, thus promoting the process of epithelial to mesenchymal transition (EMT) and finally inducing cell invasion and migration. Furthermore, serum levels of lncRNA UBE2CP3 were increased in HCC patients and decreased after surgery. Our results suggest that lncRNA UBE2CP3 promotes the metastasis of HCC and that serum lncRNA UBE2CP3 may be a new biomarker for the diagnosis of HCC.
Project description:Hepatocellular carcinoma (HCC) metastasis is largely responsible for HCC-associated recurrence and mortality. We aimed to identify metastasis-related long non-coding RNAs (lncRNAs) to understand the molecular mechanism of HCC metastasis. We first identified that miR-1258 was downregulated in HCC tissues both in The Cancer Genome Atlas (TCGA) and Sun Yat-sen University Cancer Center (SYSUCC) dataset. MiR-1258 expression negatively correlated with recurrence-free survival and overall survival of HCC patients. MiR-1258 overexpression inhibited migration and invasion of HCC cells both in vitro and in vivo, whereas miR-1258 downregulation promoted cell metastasis. Luciferase assays verified direct binding of miR-1258 to Smad2 and Smad3, thereby attenuating TGF-?/Smad signaling. We further established that lncRNA LINC01278 was a negative regulator of miR-1258. In vivo and in vitro assays demonstrated that LINC01278-mediated HCC metastasis was dependent on miR-1258 expression. Furthermore, miR-1258 downregulation in turn increased LINC01278 expression. We also observed that TCF-4 could bind to the LINC01278 promoter site. In addition, LINC01278 downregulation decreased migration and invasion of HCC cells induced by ?-catenin and TGF-?1 both in vitro and in vivo. We uncovered a novel mechanism for ?-catenin/TCF-4-LINC01278-miR-1258-Smad2/3 feedback loop activation in HCC metastasis, and the study indicated that LINC01278 could serve as a therapeutic target for HCC metastasis.
Project description:Hepatocellular carcinoma (HCC) is one of the most common malignancies with poor outcomes. The main causes of HCC-related deaths are recurrence and metastasis. Long noncoding RNAs (lncRNAs) are recently identified as critical regulators in cancers. However, the lncRNAs involved in HCC recurrence and metastasis are poorly understood. In this study, via analyzing The Cancer Genome Atlas Liver Hepatocellular Carcinoma dataset, we identified a novel lncRNA LINC01134, which is highly expressed in HCC tissues and correlated with microvascular invasion, macrovascular invasion, recurrence, and poor overall survival of HCC patients. Functional experiments revealed that ectopic expression of LINC01134 promotes HCC cell migration and invasion in vitro and HCC liver metastasis and lung metastasis in vivo. Knockdown of LINC01134 represses HCC cell migration and invasion in vitro and HCC liver metastasis and lung metastasis in vivo. Mechanistically, we found that LINC01134 directly binds the promoter of AKT1S1 and activates AKT1S1 expression. Via activating AKT1S1, LINC01134 further activates NF-?B signaling. The expression of LINC01134 is significantly positively correlated with that of AKT1S1 in HCC tissues. In line with LINC01134, AKT1S1 is also highly expressed in HCC tissues and correlated with poor survival of HCC patients. Functional rescue experiments showed that repressing AKT1S1 or NF-?B signaling abrogates the roles of LINC01134 in HCC. Taken together, these findings recognized LINC01134 as a novel oncogenic lncRNA, which indicates vascular invasion, recurrence, and poor overall survival of HCC patients. LINC01134 promotes HCC metastasis via activating AKT1S1 expression and subsequently activating NF-?B signaling. This study suggested LINC01134 as a potential prognostic biomarker and therapeutic target for HCC.
Project description:Long noncoding RNAs (lncRNAs) are emerging as critical regulators of gene expression, which play fundamental roles in cancer development. In this study, we found that <i>homeobox A11 antisense RNA (HOXA11-AS)</i>, a highly expressed lncRNA in cell lines derived from prostate cancer bone metastases, promoted the cell invasion and proliferation of PC3 prostate cancer cells. Transcription factor homeobox B13 (HOXB13) was identified as an upstream regulator of <i>HOXA11-AS.</i><i>HOXA11-AS</i> regulated bone metastasis-associated C-C motif chemokine ligand 2 (CCL2)/C-C chemokine receptor type 2 (CCR2) signaling in both PC3 prostate cancer cells and SaOS2 osteoblastic cells. The HOXB13/<i>HOXA11-AS</i> axis also regulated integrin subunits (ITGAV and ITGB1) specific to prostate cancer bone metastasis. HOXB13, in combination with <i>HOXA11-AS</i>, directly regulated the <i>integrin-binding sialoprotein</i> (<i>IBSP</i>) promoter. Furthermore, conditioned medium containing <i>HOXA11-AS</i> secreted from PC3 cells could induce the expression of <i>CCL2</i> and <i>IBSP</i> in SaOS2 osteoblastic cells. These results suggest that prostate cancer <i>HOXA11-AS</i> and HOXB13 promote metastasis by regulation of CCL2/CCR2 cytokine and integrin signaling in autocrine and paracrine manners.
Project description:OBJECTIVES:Long non-coding RNAs (LncRNAs) play an important role in hepatocellular carcinoma development, however, as a crucial driver of hepatocellular carcinoma (HCC) metastasis, their functions in tumour metastasis remain largely unknown. MATERIALS AND METHODS:The lncRNA TRERNA1 expression levels were detected in HCC by quantitative real-time PCR (qPCR). The function of TRERNA1 was examined by wound-healing assays, transwell assays and tail vein injection experiments. The potential regulatory mechanisms of TRERNA1 on its target genes were explored by ChIP, RIP, IP and WB assays. RESULTS:Elevated TRERNA1 levels promoted HCC cell migration and invasion in vitro and in vivo. TRERNA1 recruited EHMT2 to dimethylate H3K9 in the CDH1 promoter region. Furthermore, EHMT2 bound to SNAI1 to suppress CDH1 expression in HCC cells. After inhibiting TRERNA1, the expression level of CDH1 was restored and was involved in the regulation of the EHMT2/SNAI1 complex. The level of TRERNA1 was positively correlated with tumour metastasis and was negatively correlated with the expression of CDH1 in HCC tissues. CONCLUSIONS:For the first time, the current study reveals that TRERNA1 promotes cell metastasis and the invasion of HCC via the recruitment of EHMT2 and/or the EHMT2/SNAI1 complex to suppress CDH1. These data identify a novel mechanism that regulates TRERNA1 in metastatic HCC and provides a potential targeted therapy for HCC patients.
Project description:Tumor-associated macrophages have important roles in hepatocellular carcinoma (HCC) initiation and progression. Long noncoding RNAs (lncRNAs) have also been reported to be involved in HCC. In this study, we explored how lncRNA LINC00662 may influence HCC progression through both tumor cell-dependent and macrophage-dependent mechanisms. LINC00662 was found to be upregulated in HCC, and high LINC00662 levels correlated with poor survival of HCC patients. LINC00662 upregulated WNT3A expression and secretion via competitively binding miR-15a, miR-16, and miR-107. Through inducing WNT3A secretion, LINC00662 activated Wnt/?-catenin signaling in HCC cells in an autocrine manner and further promoted HCC cell proliferation, cell cycle, and tumor cell invasion, while repressing HCC cell apoptosis. In addition, acting through WNT3A secretion, LINC00662 activated Wnt/?-catenin signaling in macrophages in a paracrine manner and further promoted M2 macrophage polarization. Via activating Wnt/?-catenin signaling and M2 macrophages polarization, LINC00662 significantly promoted HCC tumor growth and metastasis in vivo. Hence, targeting LINC00662 may provide novel therapeutic strategy against HCC.
Project description:Long noncoding RNAs (lncRNAs) are a new class of regulatory noncoding RNAs. Emerging evidences indicate that lncRNAs play a critical role in the development of hepatocellular carcinoma (HCC). Although several lncRNAs have been annotated, the association of most lncRNAs with HCC is unknown. In this study, we investigated lncRNA alterations in HCC by performing lncRNA microarray analysis. We identified a novel lncRNA called HCC-associated lncRNA (HCAL) that was highly expressed in HCC tissues. HCAL upregulation was clinically associated with poor differentiation, intravascular cancer embolus, and decreased survival of patients with HCC. HCAL silencing significantly inhibited the growth and metastasis of HCC cells both in vitro and in vivo. Interestingly, transcriptome-sequencing analysis of HCAL-knockdown cells showed alterations in some cancer-related pathways. Mechanistically, HCAL directly interacted with and functioned as a sponge for microRNAs such as miR-15a, miR-196a, and miR-196b to modulate LAPTM4B expression. Taken together, our findings suggest the presence of a novel lncRNA-miRNA-mRNA regulatory network, i.e., the HCAL-miR-15a/miR-196a/miR-196b-LAPTM4B network, in HCC and indicate that HCAL may be a potential target for treating HCC.
Project description:LncRNA ANCR plays important roles in the modulation of epithelial mesenchymal transition (EMT) and tumour metastasis in many tumours. However, the role of ANCR in regulating hepatocellular carcinoma (HCC) metastasis is still not known. The current study aims to investigate the underlying mechanism for tumour oncogenesis of ANCR in HCC metastasis. HCC cell proliferation and migration/invasion were measured by MTT and Transwell assays. Xenograft model was established to determine the effect of ANCR on HCC growth and metastasis. ChIP assay was used to detect the H3 and H4 histone acetylation levels at the ANCR promoter region. RNA pull-down and RIP assay was performed to analyse the relationship between ANCR and heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1). Dual-luciferase reporter gene assay was conducted to determine the interaction between ANCR and miR-140-3p. The results indicated that ANCR was highly expressed in HCC tissues and cells, which promoted the proliferation and migration/invasion of HCC cells. <i>In vivo</i> experiments showed interfering ANCR suppressed the growth and metastasis of HCC. H3/H4 histone acetylation levels at the ANCR promoter region were elevated in HCC tissues and cells, and interfering histone deacetylases 3 (HDAC3) significantly up-regulated ANCR expression. ANCR could bind to HNRNPA1, and promoted the expression of HNRNPA1 through regulating its degradation. In addition, ANCR upregulated the expression of HNRNPA1 through sponging miR-140-3p. Finally, we found that ANCR promoted the EMT and invasion/migration of HCC cells through regulating HNRNPA1. In conclusion, ANCR promoted HCC metastasis by upregulating HNRNPA1, inhibiting HNRNPA1 degradation and sponging miR-140-3p.
Project description:Hepatocellular carcinoma (HCC) is one type of cancers whose carcinogenesis and progression are closely related to chronic inflammation. Identifying the molecular mechanisms for inflammation-related HCC progression will contribute to improve the efficacy of current therapeutics for HCC patients. Many kinds of epigenetic factors, including long non-coding RNAs (lncRNAs), have been discovered to be important in HCC growth and metastasis. However, how the lncRNAs promote HCC progression and what's the application of lncRNA silencing in vivo in suppressing HCC remain to be further investigated. Here, we found that lncRNA metastasis associated lung adenocarcinoma transcript1 (MALAT1) was upregulated in HCC tumor tissues, and knockdown of MALAT1 suppressed proliferation, cell cycle and invasion of HCC cells in response to lipopolysaccharide (LPS) stimulation. Knockdown of MALAT1 significantly inhibited LPS-induced pro-inflammatory mediators IL-6 and CXCL8 expression in HCC cells, which could be restored by overexpressing MALAT1. Mechanistically, MALAT1 recruited Brahma-related gene 1 (BRG1), a catalytic subunit of chromatin remodeling complex switching/sucrose non-fermentable (SWI/SNF), to the promoter region of IL-6 and CXCL8, and thus facilitated NF-κB to induce the expression of these inflammatory factors. Importantly, in vivo silencing of MALAT1 in HCC tissues inhibited growth of HCC xenografts, and also suppressed the expression of pro-inflammatory factors in HCC tissues accordingly. Our results demonstrate that MALAT1 promotes HCC progression by binding BRG1 to epigenetically enhance inflammatory response in HCC tissues, and silencing of MALAT1 may be a potential approach to the treatment of HCC.