Chung Yong Kim

Liver abscess after transcatheter oily chemoembolization for hepatic tumors: incidence, predisposing factors, and clinical outcome.

PURPOSE To evaluate the incidence of, predisposing factors for, and clinical outcome of liver abscess developing in patients with hepatic tumors after transcatheter oily chemoembolization (TOCE). MATERIALS AND METHODS During the past 6-year period, 2,439 patients with hepatic tumors underwent a total of 6,255 TOCE procedures. With a retrospective review of medical records, the authors evaluated the occurrence of liver abscess, the statistical significance of potential predisposing factors including portal vein obstruction, metastatic tumors, biliary abnormalities (type 1, simple biliary obstruction; type 2, status prone to ascending biliary infection), malignant gastrointestinal mucosal lesions, and additional gelatin sponge particle embolization in liver abscess formation, and the clinical outcome of abscess. RESULTS Fifteen liver abscesses occurred in 14 patients (0.2%). Liver abscesses developed in three of 987 (0.3%) TOCE procedures for portal vein obstruction, three of 114 (2.6%) procedures for metastatic tumors, one of 49 (1.8%) for type 1 biliary abnormality, four of 55 (7.4%) for type 2 biliary abnormality, two of 18 (11.1%) for malignant gastrointestinal mucosal lesion, and nine of 2,108 (0.4%) for additional gelatin sponge particle embolization. Univariate and multivariate statistical analysis showed that type 2 biliary abnormality was a significant predisposing factor. The mortality related to liver abscess occurred in two patients (13.3%). Thirteen liver abscesses were successfully treated with parenteral antibiotics and percutaneous catheter drainage. However, irreversible deterioration of liver function occurred in two patients. Two of nine further TOCE procedures in three patients caused recurrent septicemia and liver abscess. CONCLUSION The biliary abnormality prone to ascending biliary infection was the most important predisposing factor to the development of liver abscess after TOCE. Postembolic liver abscess could be effectively managed with percutaneous catheter drainage.

Helicobacter pylori induces an array of pro‐inflammatory cytokines in human gastric epithelial cells: Quantification of mRNA for interleukin‐8, ‐1α/β, granulocyte‐macrophage colony‐stimulating factor, monocyte chemoattractant protein‐1 and tumour necrosis factor‐α

Despite the fact that Helicobacter pylori is known to be non‐invasive, mucosal infiltration of inflammatory cells have been observed in the gastric mucosa. The exact pathogenesis of such an inflammatory reaction has not been well defined. We explored the repertoire of cytokine genes expressed in human gastric epithelial cells in response to coculture with H. pylori. After gastric epithelial cells, SNU‐5 and KATO III, were infected with H. pylori, expression of several cytokine genes was assessed using quantitative reverse transcription polymerase chain reaction. Interleukin (IL)‐8, ‐1α and ‐1β mRNA were expressed in both gastric epithelial cells throughout the entire infection period. In SNU‐5, IL‐1α and IL‐8 mRNA were expressed at 1 h, reached a peak level at 4 h and then decreased. Interleukin‐1β mRNA was expressed less frequently than IL‐1α or IL‐8 mRNA. In SNU‐5 cells, granulocyte‐macrophage colony‐stimulating factor (GM‐CSF), monocyte chemoattractant protein‐1 (MCP‐1), and tumour necrosis factor‐α (TNF‐α) mRNA were expressed at 9h, but was not expressed in KATO III. Gene expression paralleled the amount of IL‐8 protein measured by enzyme‐linked immunoabsorbent assay (ELISA). Interleukin‐8 mRNA expression was not observed in KATO III cells infected with Campylobacter fetus ssp. fetus, Campylobacter jejuni or Escherichia coli. IL‐8 mRNA expression was increased not only in gastric epithelial cells but also in non‐gastric cells infected with H. pylori. These results suggest that an inflammatory reaction induced by H. pylori may be initially triggered by an array of pro‐inflammatery cytokines expressed by infected gastric epithelial cells.

Identification of a Cholangiocarcinoma-Like Gene Expression Trait in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the major adult liver cancers. The existence of combined hepatocellular-cholangiocarcinoma (CHC), a histopathologic intermediate form between HCC and CC, suggests phenotypic overlap between these tumors. Here, we applied an integrative oncogenomic approach to address the clinical and functional implications of the overlapping phenotype between these tumors. By performing gene expression profiling of human HCC, CHC, and CC, we identified a novel HCC subtype, i.e., cholangiocarcinoma-like HCC (CLHCC), which expressed cholangiocarcinoma-like traits (CC signature). Similar to CC and CHC, CLHCC showed an aggressive phenotype with shorter recurrence-free and overall survival. In addition, we found that CLHCC coexpressed embryonic stem cell-like expression traits (ES signature) suggesting its derivation from bipotent hepatic progenitor cells. By comparing the expression of CC signature with previous ES-like, hepatoblast-like, or proliferation-related traits, we observed that the prognostic value of the CC signatures was independent of the expression of those signatures. In conclusion, we suggest that the acquisition of cholangiocarcinoma-like expression traits plays a critical role in the heterogeneous progression of HCC.

Gene Expression–Based Recurrence Prediction of Hepatitis B Virus–Related Human Hepatocellular Carcinoma

Purpose: The poor prognosis of hepatocellular carcinoma (HCC) is, in part, due to the high rate of recurrence even after “curative resection” of tumors. Therefore, it is axiomatic that the development of an effective prognostic prediction model for HCC recurrence after surgery would, at minimum, help to identify in advance those who would most benefit from the treatment, and at best, provide new therapeutic strategies for patients with a high risk of early recurrence. Experimental Design: For the prediction of the recurrence time in patients with HCC, gene expression profiles were generated in 65 HCC patients with hepatitis B infections. Result: Recurrence-associated gene expression signatures successfully discriminated between patients at high-risk and low-risk of early recurrence (P = 1.9 × 10−6, log-rank test). To test the consistency and robustness of the recurrence signature, we validated its prognostic power in an independent HCC microarray data set. CD24 was identified as a putative biomarker for the prediction of early recurrence. Genetic network analysis suggested that SP1 and peroxisome proliferator–activated receptor-α might have regulatory roles for the early recurrence of HCC. Conclusion: We have identified a gene expression signature that effectively predicted early recurrence of HCC independent of microarray platforms and cohorts, and provided novel biological insights into the mechanisms of tumor recurrence.

Therapeutic Efficacy of Transcatheter Arterial Chemoembolization as Compared With Hepatic Resection in Hepatocellular Carcinoma Patients With Compensated Liver Function in a Hepatitis B Virus–Endemic Area: A Prospective Cohort Study

PURPOSE Identifying a special subgroup of hepatocellular carcinoma (HCC) patients who may benefit from transcatheter arterial chemoembolization (TACE) when compared with the standard treatment of hepatic resection (HR) warrants research in Asian countries. PATIENTS AND METHODS From January 1993 to December 1994, 182 patients with operable HCC (Child-Pugh class A and International Union Against Cancer [UICC] stage T1-3N0M0) were enrolled. After initial TACE and lipiodol computed tomography, 91 received HR and 91, who refused the operation, received repeated sessions of TACE. After stratification according to the tumor stage (UICC and Cancer of the Liver Italian Program [CLIP]) and lipiodol retention pattern, the survival rates of the two treatment groups were compared. The median follow-up period was 83 months. RESULTS As of December 31, 2000, 48 patients who underwent HR and 68 patients who underwent TACE had died. In a subgroup analysis according to tumor stage, the HR group survival rate was significantly higher than the TACE group in both UICC T1-2N0M0 (P =.0058) and CLIP 0 (P =.0027) subgroups. However, there was no significant difference in either UICC T3N0M0 (P =.7512) or CLIP 1-2 (P =.5366) subgroups. Even in patients with UICC T1-2N0M0 HCC, when lipiodol was compactly retained, the survival rate of the HR group was comparable to that of the TACE group (P =.0596). CONCLUSION TACE proved to be as effective as HR in the subpopulations with UICC T3N0M0 or CLIP 1-2 HCC and adequate liver function, and even with UICC T1-2N0M0 HCC when lipiodol was compactly retained in the tumor. In such cases, the choice of treatment modality between TACE and HR may be left to the patients preference.

Genetic alterations in gallbladder adenoma, dysplasia and carcinoma

Adenoma and dysplasia in the gallbladder (GB) have been reported as precancerous lesions, but the genetic evidence of this is not clearly defined. The purpose of this study was to analyze the frequencies of K-ras, p53, and p16 gene mutations, of microsatellite instability (MI) and of loss of heterozygosity (LOH) in GB cancer, dysplasia, and adenoma. Tissues from 15 GB cancers, five dysplasias around cancerous tumors, and three adenomas were collected prospectively. The mutation rates of K-ras, p53, and p16 were 20.0, 35.7, and 30.7%, respectively, in GB cancers. However, no mutations were found in dysplasia or adenoma. Reduced staining for p16 was seen in 23% of carcinomas. All of the GB carcinomas and four out of five (80%) of the dysplasias showed LOH in a minimum of one locus, but one out of three (33%) cases of adenoma displayed LOH in only one locus. All of the loci of LOH in the dysplasias, except one, showed the same patterns of allelic loss as the adjacent carcinomas. Only one dysplasia showed multiple MI. In conclusion, multiple LOH may be associated with the development of dysplasia and the malignant transformation of GB carcinoma. Gene alterations of K-ras, p53, and p16 are important steps in the malignant changes of dysplasia. However, MI seems to have only a limited role in GB cancer development.

A genome-wide association study identified new variants associated with the risk of chronic hepatitis B

UNLABELLED Hepatitis B virus (HBV) infection is the predominant risk factor for chronic hepatitis B (CHB), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Recently, several genome-wide association studies (GWASs) of CHB identified human leukocyte antigen (HLA) loci, including HLA-DP and HLA-DQ in Asian populations, as being associated with the risk of CHB. To confirm and identify the host genetic factors related to CHB infection, we performed another GWAS using a higher-density chip in Korean CHB carriers. We analyzed 1400 samples from Korean population (400 CHB cases and 1000 population controls) using a higher-density GWAS chip [1 140 419 single nucleotide polymorphisms (SNPs)]. In subsequent replication analysis, we further analyzed in an independent study of a Korean CHB cohort consisting of 2909 Korean samples (971 cases and 1938 controls). Logistic regression methods were used for statistical analysis adjusting for age and sex as covariates. This study identified two new risk-associated loci for CHB on the HLA region of chromosome 6, e.g. rs652888 on euchromatic histone-lysine-methyltransferase 2 (EHMT2, P = 7.07 × 10(-13)) and rs1419881 on transcription factor 19 (TCF19, P = 1.26 × 10(-18)). Conditional analysis with nearby HLA CHB loci that were previously known, confirmed the independent genetic effects of these two loci on CHB. CONCLUSION The GWAS and the subsequent validation study identified new variants associated with the risk of CHB. These findings may advance the understanding of genetic susceptibility to CHB.

Fatal Submassive Hepatic Necrosis Associated with Tyrosine-Methionine-Aspartate-Aspartate-Motif Mutation of Hepatitis B Virus after Long-Term Lamivudine Therapy

We present a case of infection with lamivudine-resistant mutant hepatitis B virus (HBV) that fatally exacerbated hepatitis following the emergence of HBV with mutations in the tyrosine-methionine-aspartate-aspartate (YMDD) motif in an immunocompetent patient who was receiving long-term lamivudine therapy. Restriction fragment length polymorphism analysis showed that the YMDD-motif mutant was the predominant form of circulating HBV at the time of the fatal exacerbation, and a necropsy specimen of the liver revealed submassive hepatic necrosis without steatosis.

Helicobacter pylori Water-Soluble Surface Proteins Activate Human Neutrophils and Up-Regulate Expression of CXC Chemokines

To elucidate the mechanisms of the persistent neutrophil recruitment in H. pylori-infected gastric mucosa, we evaluated the activation of human neutrophils and CXC chemokine expression in neutrophils by H. pylori water-soluble surface proteins. H. pylori water extract (HPWE) was prepared from a supernatant of the H. pylori suspension in distilled water. After neutrophils were stimulated with HPWE, the mobilization of intracellular free calcium, the expression of lymphocyte function-associated antigen-1β, and the secretion of myeloperoxidase (MPO) were enhanced in the neutrophils. In H. pylori-infected gastric mucosa, transendothelial and transepithelial migration of neutrophils were observed by electron microscopy and mucosal MPO levels were elevated. Up-regulation of the expression of interleukin-8 (IL-8) and growth-related oncogenes (GROs; GROα, GROβ and GROγ) mRNA and protein in neutrophils by HPWE was demonstrated by quantitative reverse transcription–polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. In conclusion, H. pylori-induced neutrophil recruitment may be mediated by CXC chemokines which are expressed by neutrophils activated by H. pylori water-soluble surface proteins.

Helicobacter pylori reinfection rate and duodenal ulcer recurrence in Korea.

In the short term, the eradication of Helicobacter pylori in patients with duodenal ulcer (DU) is deemed to be clearly effective; the long-term effectiveness apparently depends on the H. pylori reinfection rate. We conducted the present study to investigate the rates of H. pylori reinfection and DU recurrence in 45 patients previously cured of DU in whom H. pylori had been eradicated. These patients underwent gastroscopy and tests for H. pylori at least 1 year after eradication. In a control group comprising 31 patients with DU who were not treated with H. pylori eradication regimen, the DU recurrence rate was checked annually for 4 years. Twenty of 45 patients (44.4%) in whom the mean follow-up period was 3.5 years were again found to be H. pylori positive, and the reinfection rate was 12.8% per year. DU recurred in 8 of these 20 (40%) but not in any nonreinfected patients. In the control group, the DU recurrence rate was 61% within 1 year, 81% within 2 years, 84% within 3 years, and 90% within 4 years. The respective recurrence rates in the 45 patients in whom the bacteria had been eradicated were 0%, 4%, 13%, and 18%. The H. pylori reinfection rate was as high as 12.8% per year in Korea, but in that the DU recurrence rate is significantly lower (p < 0.01; odds ratio, 129.5) in the H. pylori-eradicated group than in the control group, the eradication of H. pylori in DU patients is effective over the long term (at least 4 years).