Toru Wakamatsu

Histone lysine methyltransferase G9a is a novel epigenetic target for the treatment of hepatocellular carcinoma

Histone H3 lysine 9 dimethylation (H3K9me2) is mainly regulated by the histone lysine methyltransferase G9a and is associated with the repression of transcription. However, both the role of G9a and the significance of H3K9me2 in hepatocellular carcinoma (HCC) cells remain unclear. In this study, we conducted loss-of-function assay of G9a using short-hairpin RNA and pharmacological interference. Knockdown of G9a reduced H3K9me2 levels and impaired both HCC cell growth and sphere formation. However, transforming growth factor β1-induced epithelial mesenchymal transition (EMT) was not suppressed by G9a knockdown. Combined analyses of chromatin immunoprecipitation followed by sequencing and RNA-sequencing led to successful identification of 96 candidate epigenetic targets of G9a. Pharmacological inhibition of G9a by BIX-01294 resulted in both cell growth inhibition and induction of apoptosis in HCC cells. Intraperitoneal administration of BIX-01294 suppressed the growth of xenograft tumors generated by implantation of HCC cells in non-obese diabetic/severe combined immunodeficient mice. Immunohistochemical analyses revealed high levels of G9a and H3K9me2 in 36 (66.7%) and 35 (64.8%) primary HCC tissues, respectively. G9a expression levels were significantly positively correlated with H3K9me2 levels in tumor tissues. In contrast, in non-tumor tissues, G9a and H3K9me2 were only observed in biliary epithelial cells and periportal hepatocytes. In conclusion, G9a inhibition impairs anchorage-dependent and -independent cell growth, but not EMT in HCC cells. Our data indicate that pharmacological interference of G9a might be a novel epigenetic approach for the treatment of HCC.

Characteristics of patients with sorafenib-treated advanced hepatocellular carcinoma eligible for second-line treatment

SummaryBackground Regorafenib has been investigated for its efficacy and safety as a second-line treatment in patients with advanced hepatocellular carcinoma (HCC). We assessed the characteristics of patients with HCC treated with sorafenib who might be eligible for second-line treatment in general and regorafenib in particular. Methods Patients with HCC treated with sorafenib were retrospectively analyzed. We defined second-line candidate patients as maintaining Child–Pugh A and ECOG-PS ≤1 at the time of sorafenib failure. We also defined regorafenib candidate patients as follows: 1) continuing sorafenib at the time of radiological progression, 2) maintaining Child–Pugh A and ECOG-PS ≤ 1 at the time of sorafenib failure, and 3) continuing sorafenib 400 mg or more without intolerable adverse events at least 20 days of the last 28 days of treatment. Results Of 185 patients, 130 (70%) and 69 (37%) were candidates for second-line treatment and regorafenib. Child-Pugh score 6 and ECOG-PS 1 at the time of starting sorafenib were significantly lower in both second-line treatment and regorafenib candidate patients. Moreover, hand–foot skin reaction and liver failure during sorafenib treatment were associated with significantly low and high probabilities, respectively, of both Child–Pugh score > 6 and ECOG-PS > 1 at the time of sorafenib failure. Conclusion Regorafenib candidate patients after sorafenib failure are limited, and generally fewer than those who are candidates for second-line treatment. A lower Child–Pugh score and a better ECOG-PS were predictors of eligibility for second-line therapy and regorafenib treatment in sorafenib-treated patients with advanced HCC patients.

Impact of Radiofrequency Ablation-Induced Glisson’s Capsule-Associated Complications in Patients with Hepatocellular Carcinoma

Background Radiofrequency ablation (RFA) is commonly used to locally treat hepatocellular carcinoma (HCC). However, when tumors are close to the Glisson’s capsule, RFA may induce injury in this region, complicating therapeutic efforts. We investigated the impact of RFA-induced Glisson’s capsule-associated complications on liver function and prognosis of HCC patients. Methods We retrospectively reviewed our patient database and found 170 early-stage HCC patients treated via RFA from April 2004 to December 2012. We defined RFA-induced Glisson’s capsule-associated complication as lasting hepatic arterioportal (AP) fistula, major intrahepatic bile-duct dilatation (affecting two or more subsegments), or hepatic infarction. We also defined liver failure as initial occurrence of either total bilirubin increase (>3.0 mg/dL), uncontrolled ascites, or encephalopathy. Results In our cohort, 15 patients had RFA-induced Glisson’s capsule-associated complications (incidence of related complications, with some overlap: lasting AP fistula, n = 9; major intrahepatic bile-duct dilatation, n = 7; and hepatic infarction, n = 2). The cumulative incidence of liver failure before stage progression was significantly higher and the median overall survival (OS) was significantly lower (52.3 months) in HCC patients with Glisson’s capsule-associated complications than in those without Glisson’s capsule-associated complications (95.0 months). In addition, multivariate analysis demonstrated that Glisson’s capsule-associated complication was a significant independent factor associated with OS. Conclusions In this study, we have shown that early-stage HCC patients with RFA-induced Glisson’s capsule-associated complications may have higher risks in poor prognosis.

Analysis of Sorafenib Outcome: Focusing on the Clinical Course in Patients with Hepatocellular Carcinoma.

Background Treatment outcomes of sorafenib therapy may greatly vary depending not only on tumor spread but also on past clinical processes prior to sorafenib therapy and timing of sorafenib administration in the past clinical course of hepatocellular carcinoma (HCC). We evaluated the efficacy of sorafenib in patients with HCC, taking into account of their past clinical courses. Methods Patients with HCC treated with sorafenib as a first-line systemic therapy, whose courses documented from the time of the initial diagnosis, were retrospectively analyzed. Results Of the 123 patients receiving sorafenib therapy at an advanced-stage, baseline characteristics differed including the rate of hepatitis C virus, Child–Pugh class, and status of intrahepatic lesions according to stage progression processes. Overall survival (OS) in patients progressed directly from the early-stage (15.3 months) was significantly longer than that in patients diagnosed at the advanced-stage (5.3 months, P = 0.022) and progressed from the intermediate-stages (6.0 months, P = 0.041). Of 105 patients diagnosed at the intermediate-stage on past clinical courses, OS of starting sorafenib therapy before progression to the advanced-stage (67 patients) was significantly longer than for patients starting sorafenib therapy only after progression to the advanced-stage (38 patients) (P = 0.015). Conclusion Characteristic differences between past stage progression processes might affect prognosis in advanced-stage HCC patients receiving sorafenib. Switching to sorafenib therapy before progression to the advanced-stage appears more effective than that after progression to the advanced-stage in patients diagnosed in the intermediate-stage on past clinical courses prior to sorafenib administration.

Presence of non-hypervascular hypointense nodules on Gd-EOB-DTPA enhanced MRI in patients with hepatocellular carcinoma

Gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA)‐enhanced magnetic resonance imaging (MRI) performed before curative therapy for hepatocellular carcinoma (HCC) can distinguish between intrahepatic distant recurrence and hypervascularization. This study aimed to retrospectively evaluate the presence of non‐hypervascular hypointense nodules on hepatobiliary phase images from Gd‐EOB‐DTPA‐enhanced MRI as a risk factor of the intrahepatic distant recurrence of early stage HCC following radiofrequency ablation (RFA).

Fatal Diaphragmatic Hernia following Radiofrequency Ablation for Hepatocellular Carcinoma: A Case Report and Literature Review.

An 81-year-old man was admitted to our hospital because of right quadrant abdominal pain. On admission, his liver function was Child-Pugh grade C (10 points). Computed tomography (CT) revealed a diaphragmatic herniation of bowel loops into the right thoracic cavity, accompanied by pleural effusion. Although diaphragmatic hernia was successfully repaired by emergency surgery, he died of liver failure 23 days after the surgery. A retrospective reading of CT images revealed the presence of diaphragmatic injury after radiofrequency ablation (RFA) which had been conducted 33 months before the development of diaphragmatic hernia. Of importance, the lesion of the diaphragmatic injury was located on the estimated needle track of RFA for hepatocellular carcinomas in segment 5 and segment 5/8, but not adjacent to their ablation areas. Subsequently, diaphragmatic perforation had been observed 24 months before admission. This suggests that diaphragmatic hernia caused by RFA is not necessarily due to thermal damage of ablation and is possibly life-threatening, at least in some patients with an impaired liver function.

Acute Liver Failure in an Antimitochondrial Antibody- Positive 63-Year-Old Man

Antimitochondrial antibody (AMA) is one of the representative features of primary biliary cirrhosis (PBC). PBC is a female-dominant disease usually presenting intrahepatic bile duct destruction, cholestasis and fibrosis with or without chronic nonsuppurative destructive cholangitis. We presented the case of a 63-year-old man with acute liver failure who had AMA, pronounced alanine aminotransferase elevation and high bilirubinemia. We administered corticosteroids and rescued this patient without liver transplantation. It is well known that some patients within the spectrum of autoimmune liver disease present with characteristics of both PBC and autoimmune hepatitis. Although corticosteroids may be associated with a significant worsening of adverse events in patients with PBC, if acute liver failure in AMA-positive cases is progressive, the administration of corticosteroids has to be considered, as well as the preparation of urgent liver transplantation.

Transarterial chemoembolization as a substitute to radiofrequency ablation for treating Barcelona Clinic Liver Cancer stage 0/A hepatocellular carcinoma

Background and Aim Transarterial chemoembolization (TACE) is the standard procedure for treating Barcelona clinic liver cancer (BCLC) stage B hepatocellular carcinoma (HCC). However, it is often carried out in the treatment of BCLC stage 0/A HCC for various reasons. This study aimed to elucidate the prognosis for BCLC stage 0/A HCC patients treated with TACE or with radiofrequency ablation (RFA). Materials and Methods The prognosis of 242 BCLC stage 0/A HCC patients within Milan criteria who underwent initially TACE or RFA were retrospectively analyzed using propensity score matching analysis. Results The analyses of baseline patient characteristics revealed that the maximum tumor size and the proportion of BCLC stage A patients were significantly higher in patients treated with TACE than in those treated with RFA (P<0.001 and 0.047, respectively). After adjusting these factors using propensity score matching (1:3 matching), patients treated with TACE (n=32) and those treated with RFA (n=96) were further analyzed. The local recurrence rate was significantly higher in the TACE group than in the RFA group (P<0.001). However, the overall survival (OS) in HCC patients treated with TACE was comparable to that in HCC patients treated with RFA (1 year, 93.5 vs. 95.8%; 3 years, 75.4 vs. 85.8%; 5 years, 61.8 vs. 70.7%; P=0.196). Multivariate analyses followed by univariate analyses revealed that serum bilirubin level (P=0.032), serum albumin level (P=0.008), HBV-DNA (P=0.013), and tumor number (P=0.021) were independent predictors of OS. Conclusion TACE can substitute RFA at least in some patients with BCLC 0/A HCC.

Henoch-Schönlein Purpura Complicated by Hepatocellular Carcinoma

Although Henoch-Schönlein purpura (HSP) is known to be accompanied by malignancies, cases with hepatobiliary cancer are extremely rare. A 62-year-old man with palpable purpura rapidly extending to both lower legs was admitted to our hospital. He was undergoing follow-up for cirrhosis caused by chronic hepatitis B virus infection and hepatocellular carcinoma (HCC). He had renal dysfunction with hematuria and proteinuria and abdominal pain. Based on the clinical presentation and skin biopsy findings, he was diagnosed with HSP. The administration of steroids resulted in the rapid improvement of the patients symptoms and he was discharged 12 days after admission.

Successful Treatment of Hepatocellular Carcinoma Complicated by Fanconi Anemia

A 42-year-old woman with liver tumors was referred to our hospital. Her condition was complicated by Fanconi anemia, and she had undergone total laryngectomy 8 years ago. On admission, contrast-enhanced computed tomography revealed hypervascular tumors in the right hepatic lobe. Ultrasound-guided tumor biopsy revealed that the tumor comprised moderately differentiated hepatocellular carcinoma. Although the patient exhibited preserved liver function (Child-Pugh A), complete blood count revealed severe pancytopenia. Eventually, the tumor was successfully treated by transcatheter arterial embolization (TAE). Both platelet transfusion and systemic administration of antibiotics were performed. She was discharged 35 days after TAE.