The hepatitis B virus X protein (HBx) has been implicated as an oncogene in both epigenetic modifications and genetic regulation during hepatocarcinogenesis, but the underlying mechanisms are not entirely clear. Long noncoding RNAs (lncRNAs), which regulate gene expression with little or no protein-coding capacity, are involved in diverse biological processes and in carcinogenesis. We asked whether HBx could promote hepatocellular carcinoma (HCC) by regulating the expression of lncRNAs. In this study we investigated the alteration in expression of lncRNAs induced by HBx using microarrays and real-time quantitative polymerase chain reaction (PCR). Our results indicate that HBx transgenic mice have a specific profile of liver lncRNAs compared with wildtype mice. We identified an lncRNA, down-regulated expression by HBx (termed lncRNA-Dreh), which can inhibit HCC growth and metastasis in vitro and in vivo, act as a tumor suppressor in the development of hepatitis B virus (HBV)-HCC. LncRNA-Dreh could combine with the intermediate filament protein vimentin and repress its expression, and thus further change the normal cytoskeleton structure to inhibit tumor metastasis. We also identified a human ortholog RNA of Dreh (hDREH) and found that its expression level was frequently downregulated in HBV-related HCC tissues in comparison with the adjacent noncancerous hepatic tissues, and its decrement significantly correlated with poor survival of HCC patients. Conclusion: These findings support a role of lncRNA-Dreh in tumor suppression and survival prediction in HCC patients. This discovery contributes to a better understanding of the importance of the deregulated lncRNAs by HBx in HCC and provides a rationale for the potential development of lncRNA-based targeted approaches for the treatment of HBV-related HCC. (HEPATOLOGY 2013;57:1882-1892 A s one of the most common malignancies in the world, hepatocellular carcinoma (HCC) has a very high morbidity and mortality. It is a major global health challenge that affects an estimated 500,000 people worldwide each year.1 The leading cause of HCC is attributable to persistent hepatitis B virus (HBV) infection, which can result in endstage liver disease, including liver cirrhosis and HCC. The smallest open reading frame of the HBV genome, HBX, encodes the hepatitis B virus X protein (HBx) and has been implicated in hepatocarcinogenesis and considered to be oncogenic.2 Furthermore, it has been observed that about 60% of HBx transgenic mice develop HCC after the age of 18 months and that some of these tumors eventually metastasize, which Abbreviations: Dreh, down-regulated expression by HBx EMT, epithelial-to-mesenchymal transition; HBx, hepatitis B virus X protein; HCC, hepatocellular carcinoma; H&E, hematoxylin and eosin; IF, intermediate filament; lncRNA, long noncoding RNA; OS, overall survival; qRT-PCR, quantitative reverse transcription-polymerase chain reaction; RACE, rapid amplification of cDNA ends; RIP, RNA immunoprecipitation; RFS, recurrence-free survival.From the
Early-onset hepatocellular carcinoma (HCC) accounts for 15%-20% of total HCC cases in Asia, and the incidence is increasing. The low frequency of cirrhosis and poor prognosis of early-onset HCC suggests that its mechanisms may differ from late-onset HCC. Although hepatitis B virus (HBV) infection is epidemiologically associated with HCC, the role of HBV in early-onset HCC remains poorly understood. Here, we report a comparative study of HBV subgenotypes and integration in early-( £ 30) and late-onset (70) HBV-associated HCC using a novel high-throughput viral integration detection method. We report that HBV B2 is predominantly present in early-onset HCC. HBV integration is a common phenomenon, both in early-and late-onset HCC, which favors integrating into human repeat regions. Moreover, we found a breakpoint in 8q24 located between c-Myc and plasmocytoma variant translocation 1 (PVT1), which was detected in 12.4% (14 of 113) of early-onset HCCs, but only 1.4% (2 of 145) in lateonset HCCs. HBV integrating this site results in c-MYC, PVT1, and microRNA-1204 overexpression in tumors, thereby potentially contributing to the development of earlyonset HCC. Conclusion: HBV genotype and integration patterns may be distinct in early-onset HCC. Our results may shed light on HCC risk factors in young HBV carriers. Further studies are needed to elucidate at which time in tumor development this integration event occurs and whether it plays an important, causative role in HCC development or progression. (HEPATOLOGY 2015;61:1821-1831 H epatocellular carcinoma (HCC) is a common solid tumor and the third leading cause of cancer death worldwide.1 Hepatitis B virus (HBV) is a major etiological agent in China, Southeast Asia, and sub-Saharan Africa, and individuals with chronic HBV infection are at increased risk of developing HCC, particularly those with chronic liver disease and cirrhosis.2 Average age at onset of HBVassociated HCC is 50 years 3,4 ; thus, the recommendations advise HCC screening for Asian male HBV patients older than 40 and Asian female HBV patients older than 50.5 Nonetheless, incidence of HCC in patients younger than 40, especially in high-risk populations, is relatively high. 6,7 Recent studies have reported a significant prevalence and worse prognosis in early-onset HCC patients, 8,9 suggesting that there Abbreviations: ALB, albumin; bp, base pairs; DR1/2, direct repeat 1 and 2; FN1, fibronectin 1; GATM, glycine amidinotransferase; gDNA, genomic DNA; HBV, hepatitis B virus; Hbx, HBV x gene; HCC, hepatocellular carcinoma; HIVID, high-throughput viral integration detection; kb, kilobase; LC, liver cirrhosis; LINE, long interspersed nuclear elements; miR, microRNA; MLL4, myeloid/lymphoid or mixed-lineage leukemia 4; PVT1, plasmocytoma variant translocation 1; RT-PCR, reverse-transcription polymerase chain reaction; SINE, short interspersed nuclear elements; ST18, suppression of tumorigenicity 18; STAT1, signal transducer and activator of transcription 1; SYT12, synaptotagmin XII; TERT, telomerase reverse transc...
An efficient preparation of N‐succinimidyl 4‐[18F]fluorobenzoate ([18F]SFB) based on a convenient three‐step, one‐pot procedure is described. [18F]Fluorination of the precursor ethyl 4‐(trimethylammonium triflate)benzoate gave ethyl 4‐[18F]fluorobenzoate. Saponification of the ethyl 4‐[18F]fluorobenzoate with aqueous tetrapropylammonium hydroxide yielded the corresponding 4‐[18F]fluorobenzoate salt ([18F]FBA), which was then treated with N,N,N,N′‐tetramethyl‐O‐(N‐succinimidyl)uronium hexafluorophosphate. The purified [18F]SFB was used for the labeling of Avastin™ (Bevacizumab) through [18F]fluorobenzoylation of the Avastin's α‐amino groups. The decay‐corrected radiochemical yields of [18F]SFB were as high as 44% (based on [18F]fluoride (n=10) with a synthesis time of less than 60 min. [18F]Avastin was produced in decay‐corrected radiochemical yields of up to 42% (n=5) within 30 min (based on [18F]SFB). The radiochemical purities of [18F]SFB and [18F]Avastin were greater than 95%. Copyright © 2008 John Wiley & Sons, Ltd.
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