Kinya Okamoto

Combination therapy with transcatheter arterial chemoembolization and percutaneous ethanol injection compared with percutaneous ethanol injection alone for patients with small hepatocellular carcinoma

To assess whether the effectiveness of a combination of transcatheter arterial chemoembolization (TACE) and percutaneous ethanol injection (PEI) is superior to PEI alone in the treatment of patients with small hepatocellular carcinoma (HCC), a randomized controlled study was performed.

Diagnostic value of serum markers of connective tissue turnover for predicting histological staging and grading in patients with chronic hepatitis C.

Purpose. Chronic hepatitis C is an insidiously progressive disease, in which repeated assessment of liver histology is required. Various serum fibrotic markers have now been introduced. Our present aim was to assess, by receiver operating characteristic analysis, the usefulness of serum fibrotic markers for diagnosing fibrotic staging and necroinflammatory grading in chronic hepatitis C. Methods. Serum levels of procollagen type III N-terminal peptide (PIIINP), 7S fragment of type IV collagen (PIVNP), hyaluronan (HA), matrix metalloproteinase (MMP)-1, MMP-2, and tissue inhibitor of metalloproteinases (TIMP)-1 were measured in 169 patients with chronic hepatitis C. Results. The accuracy of these tests for discriminating stages greater than F2 from stages less than F1 was superior to that for discriminating stage F3 from stages less than F2. The most useful test for predicting stages greater than F2 was the serum HA test (cutoff value, 50 ng/ml; sensitivity, 75%; specificity, 80%), and the next-most useful was the serum MMP-2 test (cutoff value, 550 ng/ml; sensitivity, 75%; specificity, 70%). The usefulness of these tests for discriminating moderate grade from grades less than mild was superior to that for discriminating grades more than mild from minimal grade. The most useful test for predicting moderate grade was the serum HA test (cutoff value, 60 ng/ml; sensitivity, 77%; specificity, 74%), and the second-most useful was the serum PIVNP test (cutoff value, 6.5 ng/ml; sensitivity, 74%; specificity, 75%). The combination of the most useful and next-most useful test results increased the accuracy of the diagnosis of staging and grading. Conclusions. These serum fibrotic markers, especially the serum HA test, would be clinically useful for assessing staging and grading in patients with chronic hepatitis C.

Association of functional gene polymorphisms of matrix metalloproteinase (MMP)-1, MMP-3 and MMP-9 with the progression of chronic liver disease.

Background and Aims:  Matrix metalloproteinases (MMP) play an important role in the progression of liver fibrosis in addition to fibrogenesis. MMP‐1, MMP‐3, and MMP‐9 gene polymorphisms have been shown to influence the transcriptional activity of their respective gene promoter in an allele‐specific manner. The aim of this study was to examine the possible association of MMP‐1, MMP‐3, and MMP‐9 gene polymorphisms with the progression of chronic liver disease in the Japanese population.

The pan-deacetylase inhibitor panobinostat inhibits growth of hepatocellular carcinoma models by alternative pathways of apoptosis.

Inhibition of deacetylases represents a new treatment option for human cancer diseases. We applied the novel and potent pan-deacetylase inhibitor panobinostat (LBH589) to human hepatocellular carcinoma models and investigated by which pathways tumor cell survival is influenced. HepG2 (p53wt) and Hep3B (p53null) responded to panobinostat treatment with a reduction of cell proliferation and a significant increase in apoptotic cell death at low micromolar concentrations. Apoptosis was neither mediated by the extrinsic nor the intrinsic pathway but quantitative RT-PCR showed an upregulation of CHOP, a marker of the unfolded protein response and endoplasmic reticulum stress with subsequent activation of caspase 12. Dependent on the p53 status, a transcriptional upregulation of p21cip1/waf1, an increased phosphorylation of H2AX, and an activation of the MAPK pathway were observed. In a subcutaneous xenograft model, daily i.p. injections of 10 mg/kg panobinostat lead to a significant growth delay with prolonged overall survival, mediated by reduced tumor cell proliferation, increased apoptosis and reduced angiogenesis in tumor xenografts. Panobinostat increased the acetylation of histones H3 and H4. Panobinostat is a well tolerated new treatment option for HCC that activates alternative pathways of apoptosis, also in p53-deficient tumors.

miR-29b, miR-205 and miR-221 enhance chemosensitivity to gemcitabine in HuH28 human cholangiocarcinoma cells.

Background and Aims Cholangiocarcinoma (CCA) is highly resistant to chemotherapy, including gemcitabine (Gem) treatment. MicroRNAs (miRNAs) are endogenous, non-coding, short RNAs that can regulate multiple genes expression. Some miRNAs play important roles in the chemosensitivity of tumors. Here, we examined the relationship between miRNA expression and the sensitivity of CCA cells to Gem. Methods Microarray analysis was used to determine the miRNA expression profiles of two CCA cell lines, HuH28 and HuCCT1. To determine the effect of candidate miRNAs on Gem sensitivity, expression of each candidate miRNA was modified via either transfection of a miRNA mimic or transfection of an anti-oligonucleotide. Ontology-based programs were used to identify potential target genes of candidate miRNAs that were confirmed to affect the Gem sensitivity of CCA cells. Results HuCCT1 cells were more sensitive to Gem than were HuH28 cells, and 18 miRNAs were differentially expressed whose ratios over ± 2log2 between HuH28 and HuCCT1. Among these 18 miRNAs, ectopic overexpression of each of three downregulated miRNAs in HuH28 (miR-29b, miR-205, miR-221) restored Gem sensitivity to HuH28. Suppression of one upregulated miRNA in HuH28, miR-125a-5p, inhibited HuH28 cell proliferation independently to Gem treatment. Selective siRNA-mediated downregulation of either of two software-predicted targets, PIK3R1 (target of miR-29b and miR-221) or MMP-2 (target of miR-29b), also conferred Gem sensitivity to HuH28. Conclusions miRNA expression profiling was used to identify key miRNAs that regulate Gem sensitivity in CCA cells, and software that predicts miRNA targets was used to identify promising target genes for anti-tumor therapies.

bcl-2-specific siRNAs restore Gemcitabine sensitivity in human pancreatic cancer cells

Gemcitabine has been shown to ameliorate disease related symptoms and to prolong overall survival in pancreatic cancer.Yet, resistance to Gemcitabine is commonly observed in this tumour entity and has been linked to increased expression of anti‐apoptotic bcl‐2. We therefore investigated if and to what extend silencing of bcl‐2 by specific siRNAs (siBCL2) might enhance Gemcitabine effects in human pancreatic carcinoma cells. siBCL2 was transfected into the pancreatic cancer cell line YAP C alone and 72 hrs before co‐incubation with different concentrations of Gemcitabine. Total protein and RNA were extracted for Western‐blot analysis and quantitative polymerase chain reaction. Pancreatic cancer xenografts in male nude mice were treated intraperitoneally with siBCL2 alone, Gemcitabine and control siRNA or Gemcitabine and siBCL2 for 21 days. Combination of both methods lead to a synergistic induction of apoptosis at otherwise ineffective concentrations of Gemcitabine. Tumour growth suppression was also potentiated by the combined treatment with siBCL2 and Gemcitabine in vivo and lead to increased TUNEL positivity. In contrast, non‐transformed human foreskin fibroblasts showed only minor responses to this treatment. Our results demonstrate that siRNA‐mediated silencing of anti‐apoptotic bcl‐2 enhances chemotherapy sensitivity in human pancreatic cancer cells in vitro and might lead to improved therapy responses in advanced stages of this disease.

Assessment of ablative margin by unenhanced magnetic resonance imaging after radiofrequency ablation for hepatocellular carcinoma

PURPOSE The aim of this study was to evaluate the feasibility of magnetic resonance imaging (MRI) without a contrast agent to visualize the ablative margin after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC), compared with enhanced CT. METHODS Twenty-five HCCs in 19 patients were treated by RFA. T1-weighted MRI was performed before and after RFA, and the signal intensities of the tumors and surrounding liver tissues were measured. Treatment efficacy was assessed based on three grades: margin (+), a continuous high-intensity rim around the index tumor; margin zero, a partially discontinuous high-intensity rim; margin (-), the tumor extends beyond the high-intensity rim. RESULTS Twelve (86%) of fourteen low-intensity tumors on the pre-MRI were visualized as low-intensity tumors on post-MRI, and the ablative margins were visualized as high-intensity rims. Two (67%) of three high-intensity tumors on pre-MRI were visualized as higher-intensity tumors in the high-intensity ablative margin. Because the signal intensities of tumors and surrounding tissues in 14 tumors that were low- or high-intensity tumors on pre-MRI increased to the same extent, the tumors and ablative margin could be distinguished on post images. In 6 (75%) of the 8 iso-intensity tumors on pre-MRI, the ablative margin and tumor could also not be discriminated on post-MRI. The overall agreement between MRI and CT for the ablative margin was good (κ coefficient=0.716, p=0.00002). CONCLUSION In 82% of low- or high-intensity tumors on pre-MRI, post-MRI without a contrast agent enabled visualization of the ablative margin as a high-intensity rim, and it was possible to evaluate the ablative margin earlier and easier than with enhanced CT.

Serum matrix metalloproteinase-3 (stromelysin-1) concentration in patients with chronic liver disease

BACKGROUND/AIMS Matrix metalloproteinase (MMP)-3 plays an important role in extracellular matrix degradation, because of its broad substrate specificity and its activation of other proMMPs. Our aims in the present study were to determine whether the measurement of serum MMP-3 is clinically useful for assessing ongoing liver fibrolysis in patients with chronic liver disease. METHODS We measured the serum MMP-3 concentrations with a sandwich enzyme immunoassay in 58 patients with chronic hepatitis, 22 patients with liver cirrhosis, 45 patients with hepatocellular carcinoma and 124 healthy individuals. The liver MMP-3 content was also measured in autopsied livers. RESULTS Among the healthy controls, the serum levels of MMP-3 were about 2-fold higher in the males than in the females. In this study, the serum MMP-3 results of mainly the male group were analyzed because of the large number of male subjects. Compared to the control level, the mean serum MMP-3 concentration was 55% lower in chronic hepatitis, 53% lower in liver cirrhosis and 46% lower in hepatocellular carcinoma. There was no significant difference in the serum MMP-3 levels among the chronic hepatitis, liver cirrhosis and hepatocellular carcinoma groups. The serum MMP-3 levels were not related to the histological degree of necroinflammation or of liver fibrosis in the patients with chronic hepatitis. No significant difference in serum MMP-3 levels was observed among three Childs subgroups in the group of cirrhotic patients. In the group of patients with hepatocellular carcinoma, the serum MMP-3 levels were not related to the severity of liver function, the HCC tumor size, or the histological differentiation. The serum MMP-3 level was not correlated with serum markers for connective tissue turnover, i.e. procollagen type III peptide, 7S fragment of type IV collagen, hyaluronan and tissue inhibitor of metalloproteinase-1 in the patients with chronic liver disease or hepatocellular carcinoma. CONCLUSIONS The measurement of serum MMP-3 is of little use for assessing fibrolysis in chronically diseased livers.

Expression of oxidative stress-related molecules in circulating leukocytes and urine in patients with chronic viral hepatitis

Abstract: Aims: Oxidative stress plays a role in pathogenesis of chronic viral hepatitis. Expression of oxidative stress‐related molecules remains to be clarified.

The proMMP-2 activation rate in patients with chronic viral liver disease

BACKGROUND We previously showed that serum promatrix metalloproteinase-2 (proMMP-2) concentrations were increased in cirrhotic patients, reflecting the increase in liver proMMP-2 concentrations. We examined whether the increased proMMP-2 concentration reflects the biological matrix metalloproteinase-2 (MMP-2) activity. METHODS We measured serum concentrations of active MMP-2 and proMMP-2, and calculated the active MMP-2/proMMP-2 ratio as an index of the proMMP-2 activation rate in chronic viral liver disease. RESULTS The serum active MMP-2 concentrations were not altered in chronic liver disease, although the serum proMMP-2 concentration was markedly increased in cirrhotic patients. The active MMP-2/proMMP-2 ratio decreased with the grade of liver fibrosis, and was negatively correlated with serum levels of tissue inhibitor of metalloproteinases (TIMP)-2. CONCLUSION The proMMP-2 activation rate may be inhibited by the increased TIMP-2 in liver cirrhosis (LC), resulting in the accumulation of basement membrane collagens.