Histone methyltransferase SUV420H1/KMT5B contributes to poor prognosis in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) has a high rate of recurrence and poor prognosis, even after curative surgery. Multikinase inhibitors have been applied for HCC patients, but their effect has been restricted. This study aims to clarify the clinical impact of SUV420H1/KMT5B, one of the methyltransferases for histone H4 at lysine 20, and elucidate the novel mechanisms of HCC progression. We retrospectively investigated SUV420H1 expression using HCC clinical tissue samples employing immunohistochemical analysis (n = 350). We then performed loss-of-function analysis of SUV420H1 with cell cycle analysis, migration assay, invasion assay and RNA sequence for Gene Ontology (GO) pathway analysis in vitro, and animal experiments with xenograft mice in vivo. The SUV420H1-high-score group (n = 154) had significantly poorer prognosis for both 5-year overall and 2-year/5-year disease-free survival than the SUV420H1-low-score group (n = 196) (p < 0.001 and p < 0.05, respectively). The SUV420H1-high-score group had pathologically larger tumor size, more tumors, poorer differentiation, and more positive vascular invasion than the SUV420H1-low-score group. Multivariate analysis demonstrated that SUV420H1 high score was the poorest independent factor for overall survival. SUV420H1 knockdown could suppress cell cycle from G1 to S phase and cell invasion. GO pathway analysis showed that SUV420H1 contributed to cell proliferation, cell invasion, and/or metastasis. Overexpression of SUV420H1 clinically contributed to poor prognosis in HCC, and the inhibition of SUV420H1 could repress tumor progression and invasion both in vitro and in vivo; thus, further analyses of SUV420H1 are necessary for the discovery of future molecularly targeted drugs.

Prognostic impact of surgery and radiofrequency ablation on single nodular HCC ⩽5 cm: Cohort study based on serum HCC markers.

BACKGROUND & AIMS: Serological markers of hepatocellular carcinoma (HCC) indicate its invasiveness. We aimed to investigate whether the prognostic impact of surgical resection (SR) and radiofrequency thermal ablation (RFA) on patients with single nodular HCC ⩽5cm were different regarding positive conditions of the following three HCC markers: alpha-fetoprotein (AFP); lens culinaris agglutinin-reactive fraction of AFP; and des-γ-carboxy prothrombin. METHODS: This study reviewed 296 patients with single nodular HCC ⩽5cm with Child-Pugh grade A between 2001 and 2011 (SR, n=136; RFA, n=160). Based on positive conditions of previous HCC markers (defined as non-positive, single-positive, double-positive, and triple-positive), overall survival (OS) and prognostic factors were analyzed. RESULTS: Five-year OS rates of SR and RFA among all patients were 70.1% and 69.8%, respectively (p=0.14). However, when stratified by the positive conditions of three HCC markers, their rates of non-, single-, double-, and triple-positive patients were 60.6%, 78.2%, 54.2%, and 75.9% in the SR group, whereas rates were 83.3%, 75.7%, 62.2%, and 47.6% in the RFA group (p values between SR and RFA of each tumor marker condition were 0.45, 0.10, 0.77, and <0.01, respectively). Multivariate analyses showed that RFA itself became an independent prognostic factor in the triple-positive group, with an odds ratio of 1.78 (95% confidence interval, 1.16-2.72). CONCLUSIONS: Positive conditions of three HCC markers differently influenced survival rates of those who underwent SR and RFA when treating single nodular HCC ⩽5cm. RFA itself became an independent prognostic risk when all three HCC markers were positive. Preoperative evaluation of multiple HCC markers might become an index for selecting treatment modalities.

Adjuvant chemolipiodolization reduces early recurrence derived from intrahepatic metastasis of hepatocellular carcinoma after hepatectomy.

BACKGROUND: The recurrence of hepatocellular carcinoma is still high even after surgery. Two general recurrence patterns occur: intrahepatic metastasis (IM) and multicentric carcinogenesis (MC). The aim of this study was to investigate the effectiveness of adjuvant chemolipiodolization for reducing IM or MC recurrences after surgery. METHODS: A retrospective case-control study was carried out. From April 2005, adjuvant chemolipiodolization was performed in 63 initial hepatocellular carcinoma patients 3 months after surgery. Sixty-four patients who underwent surgery between April 2001 and March 2005 were analyzed as the control group. Recurrence-free and overall survival as well as prognostic factors were analyzed univariately and multivariately. RESULTS: The 2-year recurrence-free survival was 57% in the chemolipiodolization group and 37% in the control group (P = 0.02). However, there was no significant difference at 5 years after surgery (P = 0.09). The 5-year overall survival rates in the chemolipiodolization and the control groups were 82.4 and 55.7%, respectively (P = 0.04). Cox proportional multivariate analysis revealed that adjuvant chemolipiodolization was an independent favorable prognostic factor for 2-year recurrence-free survival, and the odds ratio [95% confidential interval] was 0.55 [0.34-0.90] (P = 0.02). However, adjuvant chemolipiodolization was not an independent favorable prognostic factor for 5-year overall survival. CONCLUSIONS: Adjuvant chemolipiodolization can reduce the risk of early recurrences, which would be mainly IM derived. However, chemolipiodolization did not reduce late phase recurrences after surgery, which would be mainly MC derived. To prevent late phase recurrences, another novel strategy would be needed.

A laparoscopic splenectomy allows the induction of antiviral therapy for patients with cirrhosis associated with hepatitis C virus.

It is difficult to treat patients with cirrhosis-associated hepatitis C with pegylated interferon (PEG-IFN) and ribavirin because of thrombocytopenia-related hypersplenism. Both safety and clinical efficacy were retrospectively analyzed for patients who underwent a laparoscopic splenectomy (LS) from January 2003 to December 2007. A total of 35 patients with cirrhosis associated with hepatitis C virus had LS for thrombocytopenia before PEG-IFN and ribavirin therapy, and all patients had thrombocytopenia, which was a contraindication for antiviral therapy. The hepatopathy was Child A in 24 patients, Child B in 10 patients, and Child C in one patient. All 35 patients increased platelet count from 48,000 +/- 15,000 to 155,000 +/- 55,000/microl (P < 0.0001) after LS. The median hospital stay and blood loss were 13.0 days (range, 8 to 57 days) and 342.0 mL (range, 5 to 2350 mL). There was no postoperative death. Twenty-nine (83%) patients had PEG-IFN and ribavirin therapy after LS; 18 had complete therapy and 11 had partial therapy. Of these, nine had a sustained virologic response. A laparoscopic splenectomy for patients with cirrhosis associated with hepatitis C virus can be performed safely and allows induction of antiviral treatment.

Combined intraoperative use of contrast-enhanced ultrasonography imaging using a sonazoid and fluorescence navigation system with indocyanine green during anatomical hepatectomy.

PURPOSE: The clear demarcation line is ideal for real-time surgical navigation imaging during hepatectomy. METHODS: The study population was comprised of 22 patients with moderate liver cirrhosis scheduled to undergo an anatomical liver resection for the treatment of hepatocellular carcinoma. This study set out to assess the clinical value of the concomitant intra-operative use of contrast-enhanced intra-operative ultrasound using Sonazoid™, and a fluorescence navigation system (PDE) with ICG, as a novel tool for patients undergoing an anatomical liver resection. RESULTS: Following portal pedicle ligation for anatomical resection, 2 min after injection of ICG, the segments to be resected were detected as a negative-brightness area using PDE fluorescence. Sonazoid™ administration provides a parenchymal transectional line, as the margin of a loss of blood flow shows a hypo-enhanced image, and the resectional line of the parenchyma can be confirmed by CE-IOUS. Although the demarcation line of the liver surface after the portal pedicle ligation was apparent in 17 patients, the resection line using PDE was clearly detected in all 22 patients (p < 0.018). CONCLUSIONS: The combined use of these methods is therefore considered to be useful and safe for surgeons, as an additional tool for performing a liver resection.

Combined use of contrast-enhanced intraoperative ultrasonography and a fluorescence navigation system for identifying hepatic metastases.

BACKGROUND: The purpose of this study was to assess the concomitant use of contrast-enhanced intraoperative ultrasound (CE-IOUS) using the new microbubble agent Sonazoid, and to assess the fluorescence navigation system (Photo Dynamic Eye, or PDE) using indocyanine green (ICG) as a novel tool for identifying colorectal metastatic lesions compared with preoperative contrast-enhanced multiple row-detected computed tomography (MDCT) and gadoxetic acid-enhanced MRI. METHODS: Thirty-two patients who underwent a liver resection for colorectal metastatic carcinoma from 2008 to 2009 were included in the present study. ICG was intravenously injected within 2 weeks of the operation. The liver was inspected with CE-IOUS using Sonazoid and PDE for visualizing small metastatic lesions. A lesion analysis was performed with the postoperative histopathological examination of the resected tissues. The clinical values of CE-IOUS and PDE to confirm the malignant lesion diagnoses were statistically evaluated. RESULTS: A total of 56 lesions were identified based on the histopathological findings of the biopsies and resected tissues; of these, 52 were confirmed to be metastases, whereas 4 were benign tumors. The numbers of identified metastases by MDCT/MRI and CE-IOUS/PDE were 46 and 51, respectively. The use of CE-IOUS and PDE improved the diagnostic sensitivity compared with the use of MDCT and EOB-MRI (98.1 vs. 88.5%, respectively; P = 0.050). CONCLUSIONS: The present results suggested that the concomitant use of CE-IOUS with the Sonazoid and PDE system may be a useful and safe method, in addition to CT or MRI.

Rectal obstruction by a giant pharmacobezoar composed of magnesium oxide: report of a case.

This report presents the rare case of a 75-year-old woman who developed a rectal obstruction caused by a pharmacobezoar, following the long-term ingestion of magnesium oxide cathartics for constipation. She was admitted to the hospital with lower abdominal pain and nausea. Abdominal computed tomography and magnetic resonance imaging showed that a huge calcified mass caused the rectal obstruction. A divided sigmoid colostomy was performed to relieve her symptoms, a colonoscopy from the distal stoma delineated a huge bezoar in the rectum, and thereafter she underwent an enterotomy. Magnesium oxide was detected in an analysis of a sample from this bezoar. Phamacobezoars resulting from laxatives or cathartics have rarely been reported. The current report showed a rectal obstruction caused by a pharmacobezoar composed primarily of magnesium oxide.

Overexpression of KDM5B/JARID1B is associated with poor prognosis in hepatocellular carcinoma.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) has high potential for recurrence, even in curative operative cases. Although several molecular-targeting drugs have been applied to recurrent HCC, their effectiveness has been limited. This study therefore aims to develop novel cancer drugs through protein methylation. METHODS: We investigated the role of KDM5B/JARID1B, a member of JmjC histone demethylase, in HCC. Expression profiles of KDM5B were examined by immunohistochemical analysis in 105 HCC clinical tissue samples. To examine functional effects of KDM5B using HCC cell lines, we performed loss-of-function analysis treated with KDM5B-specific small interfering RNAs (siKDM5B). RESULTS: All HCC cases were divided into KDM5B-positive expression group (n=54) and negative expression group (n=51). In five-year overall survival, KDM5B-positive group had poorer prognosis than KDM5B-negative (61% vs 77%, p=0.047). KDM5B-positive group had much poorer prognosis than that of the negative group, especially in HCC derived from persistent infection of hepatitis B virus (HBV) or hepatitis C virus (HCV) (54% vs 78%, p=0.015). Multivariate analysis indicated that KDM5B was the strongest risk factor for poor prognosis, especially in HCC derived from HBV/HCV. Inhibition of KDM5B could significantly suppress HCC cell proliferation through no promotion from G1 to S phase. Real-time PCR and Western blotting demonstrated that E2F1/E2F2 were downstream genes of KDM5B. CONCLUSIONS: Overexpression of KDM5B results in poor prognosis in HCC that especially derived from HBV/HCV. KDM5B appears to be an ideal target for the development of anti-cancer drugs.

Depth of Hepatic Infiltration and Lymph Node Swelling as Factors for Considering Surgery for T2-4 Gallbladder Carcinoma Patients.

BACKGROUND/AIM: The aim of the present study was to clarify if the degree of hepatic infiltration and lymph node swelling of gallbladder carcinoma (GBC) should be held as deciding factors for T2-4 GBC patients to undergo surgery. PATIENTS AND METHODS: Fifty consecutive patients with T2-4 GBC who underwent surgery were reviewed retrospectively. We investigated the preoperative information and imaging factors as predictors of survival. RESULTS: The estimated overall survival in all patients was lower in patients with hepatic infiltration ≥5 mm (n=12) than in those with <5 mm (n=38) (p=0.003). Multivariate analyses demonstrated that liver infiltration ≥5 mm (OR=2.251; 95%CI=0.906-5.596, p=0.081) and lymph node swelling (OR=2.462; 95%CI=1.034-5.859, p=0.042) were risk factors of poor survival. CONCLUSION: Our results suggested that ≥5 mm liver infiltration and lymph node swelling may serve as deciding factors for surgery consideration in GBC patients.

Whole-genome mutational landscape of liver cancers displaying biliary phenotype reveals hepatitis impact and molecular diversity.

Intrahepatic cholangiocarcinoma and combined hepatocellular cholangiocarcinoma show varying degrees of biliary epithelial differentiation, which can be defined as liver cancer displaying biliary phenotype (LCB). LCB is second in the incidence for liver cancers with and without chronic hepatitis background and more aggressive than hepatocellular carcinoma (HCC). To gain insight into its molecular alterations, we performed whole-genome sequencing analysis on 30 LCBs. Here we show, the genome-wide substitution patterns of LCBs developed in chronic hepatitis livers overlapped with those of 60 HCCs, whereas those of hepatitis-negative LCBs diverged. The subsequent validation study on 68 LCBs identified recurrent mutations in TERT promoter, chromatin regulators (BAP1, PBRM1 and ARID2), a synapse organization gene (PCLO), IDH genes and KRAS. The frequencies of KRAS and IDHs mutations, which are associated with poor disease-free survival, were significantly higher in hepatitis-negative LCBs. This study reveals the strong impact of chronic hepatitis on the mutational landscape in liver cancer and the genetic diversity among LCBs.

Integrated analysis of whole genome and transcriptome sequencing reveals diverse transcriptomic aberrations driven by somatic genomic changes in liver cancers.

Recent studies applying high-throughput sequencing technologies have identified several recurrently mutated genes and pathways in multiple cancer genomes. However, transcriptional consequences from these genomic alterations in cancer genome remain unclear. In this study, we performed integrated and comparative analyses of whole genomes and transcriptomes of 22 hepatitis B virus (HBV)-related hepatocellular carcinomas (HCCs) and their matched controls. Comparison of whole genome sequence (WGS) and RNA-Seq revealed much evidence that various types of genomic mutations triggered diverse transcriptional changes. Not only splice-site mutations, but also silent mutations in coding regions, deep intronic mutations and structural changes caused splicing aberrations. HBV integrations generated diverse patterns of virus-human fusion transcripts depending on affected gene, such as TERT, CDK15, FN1 and MLL4. Structural variations could drive over-expression of genes such as WNT ligands, with/without creating gene fusions. Furthermore, by taking account of genomic mutations causing transcriptional aberrations, we could improve the sensitivity of deleterious mutation detection in known cancer driver genes (TP53, AXIN1, ARID2, RPS6KA3), and identified recurrent disruptions in putative cancer driver genes such as HNF4A, CPS1, TSC1 and THRAP3 in HCCs. These findings indicate genomic alterations in cancer genome have diverse transcriptomic effects, and integrated analysis of WGS and RNA-Seq can facilitate the interpretation of a large number of genomic alterations detected in cancer genome.

Whole-genome sequencing of liver cancers identifies etiological influences on mutation patterns and recurrent mutations in chromatin regulators.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. We sequenced and analyzed the whole genomes of 27 HCCs, 25 of which were associated with hepatitis B or C virus infections, including two sets of multicentric tumors. Although no common somatic mutations were identified in the multicentric tumor pairs, their whole-genome substitution patterns were similar, suggesting that these tumors developed from independent mutations, although their shared etiological backgrounds may have strongly influenced their somatic mutation patterns. Statistical and functional analyses yielded a list of recurrently mutated genes. Multiple chromatin regulators, including ARID1A, ARID1B, ARID2, MLL and MLL3, were mutated in ∼50% of the tumors. Hepatitis B virus genome integration in the TERT locus was frequently observed in a high clonal proportion. Our whole-genome sequencing analysis of HCCs identified the influence of etiological background on somatic mutation patterns and subsequent carcinogenesis, as well as recurrent mutations in chromatin regulators in HCCs.