Frequent Mutations in the β-Catenin Gene in Cholangiocarcinoma

The molecular pathogenesis of cholangiocarcinoma (CC) remains unclear. β-Catenin functions in both intercellular adhesion and signal transduction. As a signaling molecule, mutations in exon 3 of the β-catenin gene encoding the regions phosphorylated by glycogen synthase kinase (GSK)-3β stabilize this protein in cytoplasm. Subsequently, accumulated β-catenin protein translocates to nuclei and up-regulates the transcriptional activity of genes involved in oncogenesis. Recently, mutations in exon 3 of the β-catenin gene were detected in various carcinomas. Using polymerase chain reaction (PCR)-single-strand conformational polymorphism (SSCP) analysis, direct sequencing and subcloning-sequencing, we investigated mutations of exon 3 of the β-catenin gene in CC. Mutations were found in 26 out of 33 (78.8%) CC tumor samples. All of the mutations were heterozygous 1-base deletions at codon 15, resulting in a stop codon at codon 46. This is the first study demonstrating the presence of β-catenin gene mutations in CC. However, it was suggested that this mutation might not be involved in deregulation of β-catenin signaling, because no correlation was observed between the β-catenin mutation and immunolocalization of β-catenin protein

Expression of DNA Methyltransferase (DNMT) 1, 3a and 3b Proteins in Human Hepatocellular Carcinoma

Alteration of aberrant DNA methylation is one of the most consistent epigenetic changes found in human cancers. DNA methylation is catalyzed by DNA methyltransferase (DNMT). In this study, we examined DNMT protein expression by immunohistochemistry in surgically resected hepatocellular carcinomas (HCCs). Sections of paraffin-embedded specimens were obtained from 95 patients with HCC between 1989 and 2002. The specimens were stained with anti-DNMTs (DNMT1, DNMT3a and DNMT3b) antibodies. There were statistically significant associations between DNMT protein expression and tumor differentiation (P < 0.05) and intrahepatic metastasis (P < 0.05). DNMT3a protein expression was significantly correlated with portal vein involvement of tumors (P < 0.05). The overall survival rates of patients with DNMT3a-positive HCCs and DNMT3b-positive HCCs were significantly lower than those of patients negative for these proteins (P < 0.005, respectively). To further evaluate the correlation between DNMT protein expression and patient survival, we classified patients into 3 groups: Group 1, DNMT1(+), 3a(–) and 3b(–); Group 2) DNMT1(+), 3a or 3b(+); and Group 3) DNMT1(+), 3a(+) and 3b(+). The overall survival rate of patients in Group 3 was significantly lower than those of patients in Groups 1 and 2 (P = 0.0009). In conclusion, the results of this study suggest that DNMT1, DNMT3a and DNMT3b are cooperatively involved in determining the extent of HCCs, and that DNMT protein overexpression in HCCs may be a predictive factor for poor survival

Investigation of the Utility and Safety of Dynamic Computed Tomography with Vasodilators

Background: Dynamic computed tomography (CT) angiography is useful for evaluating of hepatic vascularity. Although vasodilators increase hepatic blood flow, the utility of dynamic CT with vasodilators is unclear. Here we investigated the utility and safety of dynamic CT with vasodilators. Methods: A prospective case-control radiographic evaluation using abdominal dynamic CT with and without vasodilator was performed at a single center between October 2015 and September 2016. We compared the CT values in Hounsfield units of the aorta; celiac artery; and common, right, and left hepatic arteries in the arterial phase and the main trunk; right and left branches of the portal vein; and right, middle, and left hepatic veins in the portal phase with and without vasodilators. The region of interest was set in each element of the liver vasculature. Four radiological technologists independently and visually compared the scores of the portal vein (P-score) and hepatic vein (V-score) on a 5-point scale with and without vasodilators. Results: The CT values of arteries and veins using vasodilators were significantly higher than those without vasodilators. With and without vasodilators, the P-scores were 3.1 ± 1.2 and 4.0 ± 1.1 (P < 0.05) and the V-scores were 3.3 ± 1.4 and 4.3 ± 1.0 (P < 0.05). Only one patient with vasodilator use had transient hypotension and recovered immediately without medication. Conclusion: Dynamic CT with vasodilators can provides better visualization of vascular structures

C-Reactive Protein/Albumin Ratio and Prognostic Nutritional Index Are Strong Prognostic Indicators of Survival in Resected Pancreatic Ductal Adenocarcinoma

Purpose: We evaluated the clinical importance, such as the occurrence of postoperative pancreatic fistula (POPF) or prognosis, of preoperative serum markers of chronic inflammation, nutrition, and immunity, as well as that of serum tumor markers after curative resection of pancreatic ductal adenocarcinomas (PDACs). Methods: Between 2006 and 2015, 43 patients with PDACs underwent curative resection at Tottori Prefectural Central Hospital. We analyzed which preoperative indicators (i.e., C-reactive protein/albumin ratio [CAR], neutrophil/lymphocyte ratio [NLR], prognostic nutritional index [PNI], carcinoembryonic antigen [CEA], and carbohydrate antigen 19-9 [CA 19-9]) were the most relevant risk factors for occurrence of POPF and poor patient survival. Results: POPF was detected in 8/43 (18.6%) patients. One patient died of pancreatic fistula at 2 months postoperatively. Among nine candidate factors (operative procedure, operation time, tumor stage, preoperative serum amylase, preoperative CAR, NLR, PNI, CEA, and CA 19-9), we did not identify any significant risk factor for the occurrence of POPF. The 5-year overall survival (OS) rate of the 43 patients was 22.4%, and the overall median survival time was 21 months. The multivariate OS analysis demonstrated that high CAR and low PNI were strong preoperative markers of poor prognosis independently of tumor stage. Conclusions: Preoperative CAR and PNI are useful prognostic markers for patients with operable PDACs