Takahiro Einama

Co-expression of mesothelin and CA125 correlates with unfavorable patient outcome in pancreatic ductal adenocarcinoma.

Objectives: Recent studies have shown that the high affinity of mesothelin-CA125 interaction might cause intracavitary tumor metastasis. We examined the clinicopathologic significance and prognostic implication of mesothelin and CA125 expression in pancreatic ductal adenocarcinoma. Methods: Tissue samples from 66 pancreatic ductal adenocarcinomas were immunohistochemically examined. Proportion and intensity of constituent tumor cells with mesothelin and CA125 expression were analyzed and classified as high-level expression, defined as expression by more than 50% of tumor cells and/or moderate to strong staining, or low-level expression otherwise. Results: A high level of mesothelin was correlated with a higher histological grade (P = 0.049) and the level of blood vessel permeation (P = 0.0006), whereas a high level of CA125 expression was correlated with a higher recurrence rate (P = 0.015). The expression of mesothelin was strongly correlated with that of CA125 (P = 0.0041). Co-expression of mesothelin and CA125 were associated with an unfavorable patient outcome (P = 0.0062). Conclusions: This is the first report showing that co-expression of mesothelin and CA125 were in pancreatic ductal adenocarcinoma, and such co-expression is associated with a poor prognosis. Our finding suggests that co-expression of these two factors plays a significant role in the acquisition of aggressive clinical behavior.

High-level Skp2 expression in pancreatic ductal adenocarcinoma: correlation with the extent of lymph node metastasis, higher histological grade, and poorer patient outcome.

Objectives: Recent studies have shown that overexpression of S-phase kinase-associated protein 2 (Skp2) occurs in many cancers at an advanced stage. We examined the clinicopathologic significance and prognostic implication of Skp2 expression in pancreatic invasive ductal carcinoma. Methods: Tissue samples from 46 pancreatic carcinomas were examined immunohistochemically for Skp2. The proportion of constituent tumor cells with Skp2 expression was analyzed and classified as high-level nuclear expression when more than 20% of the cancer cells were positive, or low-level nuclear expression otherwise. Results: High-level Skp2 overexpression was detected in 13 (28.3%) of the 46 tumors. The incidence of high-level Skp2 was correlated with higher histological grade (P = 0.0056), the extent of lymph node metastasis (P = 0.0086), the level of lymphatic permeation (P = 0.0024), and poorer patient outcome (P = 0.0189). Multivariate analysis showed that high-level Skp2 expression was an independent predictor of overall patient survival (P = 0.0140). Conclusions: It is suggested that examination of Skp2 expression might be clinically useful for prognostication in patients with pancreatic carcinoma and that Skp2 protein might be a novel therapeutic molecular target.

Luminal membrane expression of mesothelin is a prominent poor prognostic factor for gastric cancer

Background:Mesothelin is expressed in various types of malignant tumour, and we recently reported that expression of mesothelin was related to an unfavourable patient outcome in pancreatic ductal adenocarcinoma. In this study, we examined the clinicopathological significance of the mesothelin expression in gastric cancer, especially in terms of its association with the staining pattern.Methods:Tissue specimens from 110 gastric cancer patients were immunohistochemically examined. The staining proportion and intensity of mesothelin expression in tumour cells were analysed, and the localisation of mesothelin was classified into luminal membrane and/or cytoplasmic expression.Results:Mesothelin was positive in 49 cases, and the incidence of mesothelin expression was correlated with lymph-node metastasis. Furthermore, luminal membrane staining of mesothelin was identified in 16 cases, and the incidence of luminal membrane expression was also correlated with pT factor, pStage, lymphatic permeation, blood vessel permeation, recurrence, and poor patient outcome. Multivariate analysis showed that luminal membrane expression of mesothelin was an independent predictor of overall patient survival.Conclusion:We described that the luminal membrane expression of mesothelin was a reliable prognostic factor in gastric cancer, suggesting the functional significance of membrane-localised mesothelin in the aggressive behaviour of gastric cancer cells.

Clinical impacts of mesothelin expression in gastrointestinal carcinomas

Mesothelin, C-ERC/mesothelin is a 40-kDa cell surface glycoprotein that is normally present on normal mesothelial cells lining the pleura, peritoneum, and pericardium. Moreover, mesothelin has been shown to be overexpressed in several human cancers, including virtually all mesothelioma and pancreatic cancer, approximately 70% of ovarian cancer and extra bile duct cancer, and 50% of lung adenocarcinomas and gastric cancer. The full-length human mesothelin gene encodes the primary product, a 71-kDa precursor protein. The 71-kDa mesothelin precursor is cleaved into two products, 40-kDa C-terminal fragment that remains membrane-bound via glycosylphosphatidylinositol anchor, and a 31-kDa N-terminal fragment, megakaryocyte potentiating factor, which is secreted into the blood. The biological functions of mesothelin remain largely unknown. However, results of recent studies have suggested that the mesothelin may play a role of cell proliferation and migration. In pancreatic cancer, mesothelin expression was immunohistochemically observed in all cases, but absent in normal pancreas and in chronic pancreatitis. Furthermore, the expression of mesothelin was correlated with an poorer patient outcome in several human cancers. The limited mesothelin expression in normal tissues and high expression in many cancers makes it an attractive candidate for cancer therapy. The present review discusses the expression and function of mesothelin in cancer cells and the utility of mesothelin as a target of cancer therapy.

Hepatic clearance measured with (99m)Tc-GSA single-photon emission computed tomography to estimate liver fibrosis.

AIM To evaluate the clinical utility of hepatic clearance (HC) measured with technetium-99m-diethylenetriaminepenta-acetic acid-galactosyl human serum albumin ((99m)Tc-GSA) single-photon emission computed tomography (SPECT) to estimate the degree of liver fibrosis. METHODS Seventy-eight consecutive patients who underwent initial hepatectomy due to hepatocellular carcinoma were enrolled in this study. Indocyanine green clearance (ICG R15), quantitative indices estimated by (99m)Tc-GSA [the receptor index (LHL15 and HH15) and HC via SPECT analysis], and conventional liver function tests were performed before hepatectomy. Correlations among the quantitative indices for liver functional reserve, conventional liver function tests, and the degree of liver fibrosis were evaluated. RESULTS The degree of liver fibrosis was correlated with ICG R15, HH15, LHL15, and HC. HC showed the best correlation with conventional liver function tests. According to multivariate analysis, HC and LHL15 were significant independent predictors of severe fibrosis. HC was the most valuable index for predicting severe fibrosis. CONCLUSION HC measured with (99m)Tc-GSA SPECT is a reliable index for assessing liver fibrosis before hepatectomy.

Long‑term survival and prognosis associated with conversion surgery in patients with metastatic gastric cancer

In gastric cancer, primary systemic chemotherapy is the standard approach for the management of patients with initially unresectable metastasis, and it occasionally leads to a reduction in the size of the lesion, which facilitates surgical resection. The aim of this study was to examine the prognosis of patients who were able to undergo complete resection following chemotherapy. A total of 10 patients who underwent radical surgery for stage IV primary gastric cancer after chemotherapy between 2009 and 2015 at the Department of Surgery of Hokkaido Social Work Association Obihiro Hospital (Obihiro, Japan) were retrospectively investigated. Three regimens were used (S-1, n=1; S-1 + cisplatin, n=8; and S-1 + docetaxel, n=1). The mean time from chemotherapy to surgery was 210 days. One total gastrectomy + splenectomy + colectomy, one total gastrectomy + splenectomy, four total gastrectomies and three distal gastrectomies were performed. There were two cases of pancreatic fistula formation postoperatively. All the patients survived for >1 year. Of the 10 patients, 5 survived without recurrence. The median survival time was 871.1 days after diagnosis. Therefore, curative resection after chemotherapy is associated with a better prognosis in stage IV gastric cancer patients.

Huge hepatocellular carcinoma greater than 10 cm in diameter worsens prognosis by causing distant recurrence after curative resection

This study aimed to evaluate the impact of huge (≥10 cm) hepatocellular carcinoma (HCC) to the recurrence pattern and the prognosis after hepatectomy.

The anti-mesothelin monoclonal antibody amatuximab enhances the anti-tumor effect of gemcitabine against mesothelin-high expressing pancreatic cancer cells in a peritoneal metastasis mouse model

Pancreatic cancer often has a very poor prognosis, even after complete resection. The recurrence of hepatic and peritoneal metastases is an important prognostic factor; therefore, the development of improved adjuvant therapy is urgently required. Mesothelin is a cell surface glycoprotein whose expression is restricted to a variety of cancer types, including pancreatic cancer. This expression pattern makes mesothelin an attractive target for cancer therapy, and several agents targeting mesothelin are currently in clinical trials. Here, we used the chimerized high-affinity anti-mesothelin monoclonal antibody amatuximab to investigate its effect on peritoneal metastasis. We used the AsPC-1 pancreatic cancer cell line engineered to express Gaussia luciferase (Gluc), (AsPC-1-Gluc) for in vivo experiments. Results showed that while amatuximab was not directly cytotoxic on an AsPC-1-Gluc tumor cells in a peritoneal metastasis model, it prevented the formation of tumor growth. In combination therapy with gemcitabine, amatuximab exhibited synergistic killing. Our results suggest that blockade of mesothelin by amatuximab may be a useful strategy for preventing the peritoneal dissemination of pancreatic cancer under an adjuvant setting.

Cytoplasmic CD133 expression correlates with histologic differentiation and is a significant prognostic factor in extrahepatic bile duct cancer and gallbladder cancer

Prominin-1 (CD133) is one of the most important stem cell markers among various malignant tumor types, but the clinicopathological significance of CD133 expression in intrahepatic cholangiocarcinoma remains controversial. To the best of our knowledge, there have been no reports on extrahepatic bile duct cancer (EHBDCA) and gallbladder cancer (GBCA). The present study examined the clinicopathological significance of CD133 expression in EHBDCA and GBCA. Immunohistochemistry was used to evaluate CD133 expression in resected specimens obtained from 82 patients with EHBDCA and GBCA, and this expression was compared with the clinicopathological parameters and survival data of the patients. Cytoplasmic CD133 expression was identified in 20 patients, and its incidence was significantly associated with histopathological grade (P=0.035), pT factor (P=0.020) and recurrence (P=0.046). Survival analysis revealed that cytoplasmic CD133 expression in patients was significantly associated with a poorer overall survival (OS) and relapse-free survival (RFS) compared with those without cytoplasmic expression (5-year OS rate, 11.6% vs. 39.1%; 3-year RFS rate, 12.5% vs. 42.0%, respectively). Multivariate analysis revealed that cytoplasmic CD133 expression was an independent prognostic factor for OS and RFS (P=0.0036 and P<0.0001, respectively). To the best of our knowledge, this is the first report demonstrating that cytoplasmic CD133 expression was associated with histologic differentiation, cancer progression, recurrence and poor prognosis in EHBDCA and GBCA. CD133 expression may be a useful marker for clinical prognosis in patients with EHBDCA and GBCA.

L-Carnitine supplementation reduces the general fatigue of cancer patients during chemotherapy

L-Carnitine (LC) plays an important role in the metabolism of fatty acids, and LC deficiency is associated with a feeling of weakness or general fatigue. Cancer patients receiving chemotherapy often develop LC deficiency, which is considered to be a factor contributing to general fatigue. The aim of the present study was to evaluate the efficacy of LC supplementation as a treatment for general fatigue in cancer patients during chemotherapy. A total of 11 cancer patients who were suffering from general fatigue during chemotherapy in our hospital between September 2014 and December 2015 were examined (6 cases involved adjuvant chemotherapy and 5 cases involved chemotherapy for unresectable or recurrent disease). The patients were administered 1,500 mg/day of levocarnitine per os, and the change in mean daily fatigue from the baseline to 8 weeks was assessed using the Brief Fatigue Inventory. The change in the plasma levels of albumin and the lymphocyte counts from the baseline to 8 weeks were also assessed. LC supplementation reduced general fatigue in all cases. Moreover, LC supplementation maintained the plasma levels of albumin and lymphocyte counts during chemotherapy, and enabled patients to continue chemotherapy sequentially without dose reduction. Therefore, LC supplementation improved general fatigue in all the examined cancer patients during chemotherapy. This treatment may make improve the tolerability of chemotherapy in cancer patients by reducing general fatigue and improving the nutritional status.