Project description:Hepatocarcinogenesis is a multistep process involving progression from cirrhosis, to low-grade dysplastic nodule, to high-grade dysplastic nodule (HGDN) and, eventually, to hepatocellular carcinoma (HCC). Early detection of HCC is challenging as the differential diagnosis between HGDN and early HCC (eHCC) is difficult. The aim of the present study was to identify a novel biomarker to specifically differentiate between HGDN and eHCC, which may facilitate early diagnosis of HCC. Immunohistochemistry was performed to determine the expression of heterogeneous nuclear ribonucleoprotein A3 (HNRNPA3) in cirrhosis, dysplastic nodules (DNs), well-differentiated HCC and progressed HCC. The staining was evaluated by assigning a staining intensity score of 0-3 and a percentage of positively stained cells score of 0-4. Receiver operator characteristic (ROC) curve analysis was used to assess the ability of HNRNPA3 expression to differentiate between DNs and HCC. HNRNPA3 expression increased in a stepwise trend in non-tumor hepatic tissue, DNs, eHCC and progressed HCC. ROC curves revealed that HNRNPA3 expression could be used to differentiate between HGDN and eHCC, particularly in combination with glypican 3 (GPC3), with a specificity of 100%. Moreover, HNRNPA3 expression was associated with HCC differentiation. In addition, high expression of HNRNPA3 was found to be associated with poor survival rates in patients with HCC. These findings demonstrated that HNRNPA3 combined with GPC3 is a helpful diagnostic biomarker in the differential diagnosis during the multistep process of hepatocarcinogenesis, particularly in the differential diagnosis between HGDN and eHCC. To the best of our knowledge, this is the first study to report the significance of HNRNPA3 in hepatocarcinogenesis and its potential role in carcinogenesis.
Project description:Common genetic traits are not well defined in hepatocellular carcinoma (HCC), because necroinflammation lasting long in prior to hepatocarcinogenesis embeds highly heterogenous genetic background in hepatocytes over the liver. We experienced a rare case with chronic hepatitis C, in which multiple liver tumors at different stages in multistep hepatocarcinogenesis were observed at the same time. Under the same genetic and etiological backgrounds, comparisons of expression profiles among dysplastic nodules (DN), well differentiated HCC (WEL), and moderately differentiated HCC (MOD) would provide critical genetic information for the initiation and progression of HCC.
Project description:Background/aimTransforming growth factor-beta (TGF-β) has a dichotomous role, functioning as a tumor suppressor and tumor promoter. TGF-β signatures, explored in mouse hepatocytes, have been reported to predict the clinical outcomes of hepatocellular carcinoma (HCC) patients; HCCs exhibiting early TGF-β signatures showed a better prognosis than those with late TGF-β signatures. The expression status of early and late TGF-β signatures remains unclear in defined lesions of human B-viral multistep hepatocarcinogenesis.MethodsThe expression of TGF-β signatures, early and late responsive signatures of TGF-β were investigated and analyzed for their correlation in cirrhosis, low-grade dysplastic nodules (DNs), high-grade DNs, early HCCs and progressed HCCs (pHCCs) by real-time PCR and immunohistochemistry.ResultsThe expression levels of TGF-β signaling genes (TGFB1, TGFBR1, TGFBR2 and SMAD4) gradually increased with the progression of hepatocarcinogenesis, peaking in pHCCs. The expression of early responsive genes of TGF-β (GADD45B, FBP1, CYP1A2 and CYP3A4) gradually decreased, and that of the late TGF-β signatures (TWIST and SNAI1) significantly increased according to the progression of multistep hepatocarcinogenesis. Furthermore, mRNA levels of TWIST and SNAI1 were well correlated with those of stemness markers, with upregulation of TGF-β signaling, whereas FBP1 expression was inversely correlated with that of stemness markers.ConclusionsThe enrichment of the late responsive signatures of TGF-β with induction of stemness is considered to be involved in the progression of the late stage of multistep hepatocarcinogenesis, whereas the early responsive signatures of TGF-β are suggested to have tumor-suppressive roles in precancerous lesions of the early stage of multistep hepatocarcinogenesis.
Project description:Cancer stem cells (CSCs), a subset of tumor cells, contribute to an aggressive biological behavior, which is also affected by the tumor stroma. Despite the role of CSCs and the tumor stroma in hepatocellular carcinoma (HCC), features of stemness have not yet been studied in relation to tumor stromal alterations in multistep hepatocarcinogenesis. We investigated the expression status of stemness markers and tumor stromal changes in B viral carcinogenesis, which is the main etiology of HCC in Asia. Stemness features of tumoral hepatocytes (EpCAM, K19, Oct3/4, c-KIT, c-MET, and CD133), and tumor stromal cells expressing ?-smooth muscle actin (?-SMA), CD68, CD163, and IL-6 were analyzed in 36 low grade dysplastic nodules (DNs), 48 high grade DNs, 30 early HCCs (eHCCs), and 51 progressed HCCs (pHCCs) by immunohistochemistry or real-time PCR. Stemness features (EpCAM and K19 in particular) were progressively acquired during hepatocarcinogenesis in combination with enrichment of stromal cells (CAFs, TAMs, IL-6+ cells). Stemness features were seen sporadically in DNs, more consistent in eHCCs, and peaked in pHCCs. Likewise, stromal cells were discernable in DNs, showed up as consistent cell densities in eHCCs and peaked in pHCCs. The stemness features and tumor stromal alterations also peaked in less differentiated or larger HCCs. In conclusion, progression of B viral multistep hepatocarcinogenesis is characterized by an enrichment of stemness features of neoplastic hepatocytes and a parallel alteration of the tumor stroma. The modulation of neoplastic hepatocytes and stromal cells was at low levels in precancerous lesions (DNs), consistently increased in incipient cancer (eHCCs) and peaked in pHCCs. Thus, in B viral hepatocarcinogenesis, interactions between CSCs and the tumor stroma, although starting early, seem to play a major role in tumor progression.
Project description:The nonsense-mediated mRNA decay (NMD) pathway is a well-known eukaryotic surveillance mechanism that eliminates aberrant mRNAs that contain a premature termination codon (PTC). The UP-Frameshift (UPF) proteins, UPF1, UPF2, and UPF3, are essential for normal NMD function. Several NMD substrates have been identified, but detailed information on NMD substrates is lacking. Here, we noticed that, in Arabidopsis, most of the mRNA-like nonprotein-coding RNAs (ncRNAs) have the features of an NMD substrate. We examined the expression profiles of 2 Arabidopsis mutants, upf1-1 and upf3-1, using a whole-genome tiling array. The results showed that expression of not only protein-coding transcripts but also many mRNA-like ncRNAs (mlncRNAs), including natural antisense transcript RNAs (nat-RNAs) transcribed from the opposite strands of the coding strands, were up-regulated in both mutants. The percentage of the up-regulated mlncRNAs to all expressed mlncRNAs was much higher than that of the up-regulated protein-coding transcripts to all expressed protein- coding transcripts. This finding demonstrates that one of the most important roles of NMD is the genome-wide suppression of the aberrant mlncRNAs including nat-RNAs.
Project description:Ocular neovascularization is a pathological sequel of multiple eye diseases. Based on the anatomical site into which the abnormal neovessels grow, ocular neovascularization can be categorized into corneal neovascularization, choroidal neovascularization, and retinal neovascularization. Each category is intractable, and may lead to blindness if not appropriately treated. However, the current therapeutic modalities, including laser photocoagulation, vitrectomy surgery, and anti-VEGF drugs, raise concerns due to limited efficacy, damage on retinal parenchyma and vasculature, and the patients' unresponsiveness to the treatments. Therefore, the in-depth study on pathogenesis of and the search for novel therapeutic targets to the ocular neovascularization are needed. During the last 10 years or so, a large number of literatures have emerged indicating a critical role of noncoding RNAs, particularly microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), in the pathogenesis and regulation of the ocular neovascularization. This review summarizes the current understanding of the biosynthesis and functions of the miRNAs and lncRNAs, the regulation of the miRNAs and lncRNAs in neovascular eye diseases, as well as the roles of these noncoding RNAs in the disease models of ocular neovascularization, in the hope that it could provide clues for the pathogenesis of and molecular targets to the ocular neovascularization.
Project description:The microRNA 21 (miR-21) is upregulated in almost all known human cancers and is considered a highly potent oncogene and potential therapeutic target for cancer treatment. In the liver, miR-21 was reported to promote hepatic steatosis and inflammation, but whether miR-21 also drives hepatocarcinogenesis remains poorly investigated in vivo. Here we show using both carcinogen (Diethylnitrosamine, DEN) or genetically (PTEN deficiency)-induced mouse models of hepatocellular carcinoma (HCC), total or hepatocyte-specific genetic deletion of this microRNA fosters HCC development-contrasting the expected oncogenic role of miR-21. Gene and protein expression analyses of mouse liver tissues further indicate that total or hepatocyte-specific miR-21 deficiency is associated with an increased expression of oncogenes such as Cdc25a, subtle deregulations of the MAPK, HiPPO, and STAT3 signaling pathways, as well as alterations of the inflammatory/immune anti-tumoral responses in the liver. Together, our data show that miR-21 deficiency promotes a pro-tumoral microenvironment, which over time fosters HCC development via pleiotropic and complex mechanisms. These results question the current dogma of miR-21 being a potent oncomiR in the liver and call for cautiousness when considering miR-21 inhibition for therapeutic purposes in HCC.
Project description:The number of annotated long noncoding RNAs (lncRNAs) continues to grow; however, their functional characterization in model organisms has been hampered by the lack of reliable genetic inactivation strategies. While partial or full deletions of lncRNA loci disrupt lncRNA expression, they do not permit the formal association of a phenotype with the encoded transcript. Here, we examined several alternative strategies for generating lncRNA null alleles in zebrafish and found that they often resulted in unpredicted changes to lncRNA expression. Removal of the transcription start sites (TSSs) of lncRNA genes resulted in hypomorphic mutants, due to the usage of either constitutive or tissue-specific alternative TSSs. Deletions of short, highly conserved lncRNA regions can also lead to overexpression of truncated transcripts. In contrast, knock-in of a polyadenylation signal enabled complete inactivation of malat1, the most abundant vertebrate lncRNA. In summary, lncRNA null alleles require extensive in vivo validation, and we propose insertion of transcription termination sequences as the most reliable approach to generate lncRNA-deficient zebrafish.
Project description:Long noncoding RNAs (lncRNAs) have emerged as important in cancer development and progression. The impact of diet on lncRNA expression is largely unknown. Sulforaphane (SFN), obtained from vegetables like broccoli, can prevent and suppress cancer formation. Here we tested the hypothesis that SFN attenuates the expression of cancer-associated lncRNAs. We analyzed whole-genome RNA-sequencing data of normal human prostate epithelial cells and prostate cancer cells treated with 15 μM SFN or dimethylsulfoxide. SFN significantly altered expression of ~100 lncRNAs in each cell type and normalized the expression of some lncRNAs that were differentially expressed in cancer cells. SFN-mediated alterations in lncRNA expression correlated with genes that regulate cell cycle, signal transduction and metabolism. LINC01116 was functionally investigated because it was overexpressed in several cancers, and was transcriptionally repressed after SFN treatment. Knockdown of LINC01116 with siRNA decreased proliferation of prostate cancer cells and significantly up-regulated several genes including GAPDH (regulates glycolysis), MAP1LC3B2 (autophagy) and H2AFY (chromatin structure). A four-fold decrease in the ability of the cancer cells to form colonies was found when the LINC01116 gene was disrupted through a CRISPR/CAS9 method, further supporting an oncogenic function for LINC01116 in PC-3 cells. We identified a novel isoform of LINC01116 and bioinformatically investigated the possibility that LINC01116 could interact with target genes via ssRNA:dsDNA triplexes. Our data reveal that chemicals from the diet can influence the expression of functionally important lncRNAs, and suggest a novel mechanism by which SFN may prevent and suppress prostate cancer.
Project description:genome-wide methylome and transcriptome profiling of cirrhotic liver, low- and high-grade dysplastic lesions, eHCC and pHCC synchronouCLy detected in HCC patients with chronic hepatitis B infection. Identification of molecular epi-drivers by integrative analyses and validation in two independent cohorts comprising 933 HCC.