Kanako Kubota

IgG4-related sclerosing cholangitis and autoimmune pancreatitis: histological assessment of biopsies from Vater's ampulla and the bile duct.

Background and Aim:  Autoimmune pancreatitis is commonly associated with immunoglobulin (Ig) G4‐related sclerosing cholangitis (IgG4‐SC). The discrimination between IgG4‐SC and pancreatobiliary malignancies or primary sclerosing cholangitis (PSC) is now an important issue. The present study was carried out to examine the usefulness of endoscopic biopsies from Vaters ampulla and the bile duct to diagnose IgG4‐SC.

Endoscopic retrograde cholangiography versus peroral cholangioscopy to evaluate intraepithelial tumor spread in biliary cancer

BACKGROUND AND STUDY AIMS Localized-type bile duct carcinoma (LBDC) is often accompanied by extensive intraepithelial tumor spread (ITS) of 2 cm or more, which makes radical resection more difficult. This retrospective case review compares the diagnostic accuracy of endoscopic retrograde cholangiography (ERC) and peroral cholangioscopy (POCS) to detect ITS beyond the visible LBDC. PATIENTS AND METHODS Forty-four consecutive patients with LBDC diagnosed between April 2004 and October 2008 who underwent radical resection with histopathological analysis were included in this study. Extensive ITS was found histopathologically in one-third of the cases (32 %). The outcome parameters were the presence or absence of extensive ITS and the extent of extensive ITS proximal and distal to the main tumor. RESULTS In six cases it was not possible to pass the cholangioscope through the tumor sites. ERC correctly identified the presence of extensive ITS in 11/14 cases and did not yield any false-positive results. The three cases in which ERC was negative were all correctly identified by POCS plus biopsy since the cholangioscope could be passed in all three cases. The extent of extensive ITS was correctly diagnosed by ERC alone, ERC with POCS, and ERC with POCS plus mapping biopsy in 22 %, 77 %, and 100 % of cases, respectively. CONCLUSIONS The presence of extensive ITS was correctly detected in 80 % of cases by ERC alone. POCS with mapping biopsy provided perfect diagnostic accuracy not only of the presence or absence but also of the extent of extensive ITS. However, POCS has the limitation that the cholangioscope cannot be passed through the tumor sites in approximately 15 % of cases.

Large T Antigen Promotes JC Virus Replication in G2-arrested Cells by Inducing ATM- and ATR-mediated G2 Checkpoint Signaling

Large T antigen (TAg) of the human polyomavirus JC virus (JCV) possesses DNA binding and helicase activities, which, together with various cellular proteins, are required for replication of the viral genome. We now show that JCV-infected cells expressing TAg accumulate in the G2 phase of the cell cycle as a result of the activation of ATM- and ATR-mediated G2 checkpoint pathways. Transient transfection of cells with a TAg expression vector also induced G2 checkpoint signaling and G2 arrest. Analysis of TAg mutants with different subnuclear localizations suggested that the association of TAg with cellular DNA contributes to the induction of G2 arrest. Abrogation of G2 arrest by inhibition of ATM and ATR, Chk1, and Wee1 suppressed JCV genome replication. In addition, abrogation of the G2-M transition by Cdc2 depletion disabled Wee1 depletion-induced suppression of JCV genome replication, suggesting that JCV replication is facilitated by G2 arrest resulting from G2 checkpoint signaling. Moreover, inhibition of ATM and ATR by caffeine suppressed JCV production. The observation that oligodendrocytes productively infected with JCV in vivo also undergo G2 arrest suggests that G2 checkpoint inhibitors such as caffeine are potential therapeutic agents for JCV infection.

Impact of Diagnostic Ureteroscopy on Intravesical Recurrence and Survival in Patients With Urothelial Carcinoma of the Upper Urinary Tract

PURPOSE We determined whether diagnostic ureteroscopy for upper urinary tract cancer affects intravesical recurrence and cancer specific mortality. MATERIALS AND METHODS In a retrospective, multi-institutional study we evaluated 208 patients undergoing nephroureterectomy for upper urinary tract cancer who had no perioperative systemic chemotherapy, history of invasive bladder cancer, distant metastasis or incomplete followup data. Of these 208 patients 55 who composed the study group underwent diagnostic ureteroscopy before nephroureterectomy while 153 serving as controls did not. We analyzed intravesical recurrence and cancer specific survival using the Kaplan-Meier method with the log rank test used to assess significance. RESULTS There was no significant difference between the 2 groups in patient characteristics or upper urinary tract cancer stage and grade while followup, and the proportion of multiple tumors and lymphovascular invasion positive tumors were significantly greater in controls. The 2-year bladder recurrence-free survival rate was 60.0% in the study group and 58.7% in controls. There was no significant difference in the intravesical recurrence rate between the 2 groups (log rank test p = 0.972). Estimated Kaplan-Meier cancer specific survival was 88.3% and 78.1% at 5 years in the study and control groups, respectively (log rank test p = 0.0687). CONCLUSIONS Diagnostic ureteroscopy did not affect intravesical recurrence or cancer specific survival in patients with upper urinary tract cancer undergoing nephroureterectomy.

Role of lymph node dissection in the treatment of urothelial carcinoma of the upper urinary tract: Multi-institutional relapse analysis and immunohistochemical re-evaluation of negative lymph nodes

AIM To determine the role of lymph node dissection (LND) in the treatment of urothelial carcinoma (UC) of the upper urinary tract (UUT). PATIENTS AND METHODS [Study-1] A retrospective multi-institutional study evaluated 293 patients undergoing predominantly nephroureterectomy for UC of the UUT. Of 293 patients, 267 patients had pure UC and 26 demonstrated other histological components. Regarding the pathological node status, 130 patients had pN0 disease, 141 patients had pNx disease and 22 patients had pN+ disease. The sites of initial recurrence and time to first recurrence were reviewed. The sites of recurrence were classified as locoregional or distant recurrence. The relationship between node status and future recurrence was analyzed. [Study-2] Fifty-one patients treated by nephroureterectomy at Hokkaido University Hospital were included. All had LND and all LNs were negative on hematoxylin and eosin staining. We re-evaluated the presence of micrometastasis in LND specimens by anti-cytokeratin immunohistochemistory. RESULTS [Study-1] Of 293 patients, 76 developed disease relapse. Regional lymph node recurrence was the most common site (34 patients). On multivariate analyses that adjusted for the effect of tumor stage and tumor grade, pNx (skipping LND) was an adverse factor not only for locoregional recurrence, but also for distant relapse. [Study-2] Immunohistochemistry identified micrometastases in 7 (14%) of 51 patients. Regarding survival, 5 of these 7 patients with micrometastases were alive at last follow-up. CONCLUSIONS On relapse analysis, skipping LND was an adverse factor not only for locoregional recurrence, but also for distant relapse. Immunohistochemistry detected micrometastases in about 14% of patients previously diagnosed as pN0. These findings further support a potential therapeutic benefit of LND by eliminating micrometastases.

Long-Term Hepatic Allograft Acceptance Based on CD40 Blockade by ASKP1240 in Nonhuman Primates

Blockade of the CD40–CD154 costimulatory signal is an attractive strategy for immunosuppression and tolerance induction in organ transplantation. Treatment with anti‐CD154 monoclonal antibodies (mAbs) results in potent immunosuppression in nonhuman primates (NHPs). Despite plans for future clinical use, further development of these treatments was halted by complications. As an alternative approach, we have been focusing on the inhibition of the counter receptor, CD40 and have shown that a novel human anti‐CD40 mAb, ASKP1240, markedly prolongs renal allograft survival in NHPs, although allografts eventually underwent chronic allograft nephropathy. On the basis of our previous findings that a CD40–CD154 costimulation blockade induces tolerance to hepatic, but not cardiac, allografts in rodents, we tested here our hypothesis that a blockade of CD40 by ASKP1240 allows acceptance of hepatic allografts in NHPs. A 2‐week ASKP1240 induction treatment prolonged liver allograft survival in NHPs; however, the graft function deteriorated due to chronic rejection. In contrast, a 6‐month ASKP1240 maintenance monotherapy efficiently suppressed both cellular and humoral alloimmune responses and prevented rejection on the hepatic allograft. No serious side effects, including thromboembolic complications, were noted in the ASKP1240‐treated monkeys. We conclude that CD40 blockade by ASKP1240 would be a desirable immunosuppressant for clinical liver transplantation.

Clinicopathological analysis of early-stage gastric cancers detected after successful eradication of Helicobacter pylori.

Background and Aims:  The results of a randomized controlled study and meta‐analysis study have recently proved that Helicobacter pylori eradication has a preventive effect against the development of metachronous and primary gastric cancer. However, gastric cancer is sometimes detected after successful eradication. There is a lack of study about gastric cancers in eradicated patients. To clarify the characteristics of gastric cancers detected after H. pylori eradication, we analyzed the clinicopathological features of these cancers.

THE ROLE OF LYMPH-NODE DISSECTION IN THE TREATMENT OF UPPER URINARY TRACT CANCER: A MULTI-INSTITUTIONAL STUDY

To determine the role of lymph‐node (LN) dissection in patients undergoing surgery for upper urinary tract (UUT) cancer.

Role of lymph node density in predicting survival of patients with lymph node metastases after radical cystectomy: a multi-institutional study.

Objectives:  To evaluate the prognostic role of different clinico‐pathological parameters in node‐positive patients treated by radical cystectomy.

Differential LC−MS-Based Proteomics of Surgical Human Cholangiocarcinoma Tissues

Cholangiocarcinoma is an intractable cancer for which there is no effective therapy other than surgical resection, and many patients are not candidates for this treatment. Even for patients who undergo surgical resection, the 5-year survival rate is low. One reason for this is that the disease is often detected in late stages. Thus, there is a clear need for better biomarkers to facilitate early diagnosis and prognostication. During the biomarker discovery phase of our study, we used LC-MS-based proteomics with spectral counting, a semiquantitative approach to differential expression profiling, in paired cancerous and normal bile duct tissue samples from two cases. In total, 38 proteins up-regulated in the cancer samples were identified. These were verified using a SILAC method for MS-based validation. The results led to the identification of well-characterized proteins and proteins of unknown function that are up-regulated in cholangiocarcinoma. We used immunoblot analysis to validate four candidate biomarkers, actinin-1, actinin-4, protein DJ-1 and cathepsin B, with the test case samples and four additional cholangiocarcinoma case samples. Each of the four candidate proteins was overexpressed in a subset of five of the six cases tested. By immunohistochemistry, we further confirmed that expression of these proteins was elevated in cancer cells as compared with normal bile duct cells. Thus, we successfully identified several proteins up-regulated in cholangiocarcinoma. These proteins are candidate biomarkers and may also help to provide new insights into our understanding of the disease.