Tadashi Uwagawa

Phase II study of gemcitabine in combination with regional arterial infusion of nafamostat mesilate for advanced pancreatic cancer.

Purpose:To evaluate the efficacy of regional arterial infusion of the synthetic serine protease inhibitor nafamostat mesilate combined with gemcitabine for the treatment of patients with unresectable locally advanced or metastatic pancreatic cancer. Materials and Methods:A single-arm, single center, institutional review board-approved phase II trial was conducted. Thirty-five of 38 consecutive patients were included in the study. Patients received nafamostat mesilate (4.8 mg/kg continuous regional arterial infusion) with gemcitabine (1000 mg/m2 intravenously) on days 1, 8, and 15. This treatment was repeated at 28-day intervals. The primary endpoints were to evaluate overall survival and 1-year survival rate. The secondary endpoints were to assess therapeutic response and clinical benefit response. Overall survival times were estimated by the Kaplan-Meier survival analysis. Results:The median survival time was 10.0 months, and the 1-year survival rate was 40.0%. The response rate and disease control rate were 17.1% and 88.6%, respectively. A fraction of 25% of the patients who required opioids for cancer-related pain could reduce their opioid intake, and 37.1% of the patients showed healthy weight gain. Among the patients with metastatic pancreatic cancer, the median survival time was 9.0 months, and the 1-year survival rate was 32.0%. The proposed regimen offers an economic advantage compared with recent therapy regimens that have shown significant improvements in median survival over standard chemotherapy with gemcitabine. Conclusions:An alternative regimen for unresectable pancreatic cancer, especially for metastatic pancreatic cancer, is proposed based on acceptable survival time, clinical benefit, and cost advantage.

Combination chemotherapy of serine protease inhibitor nafamostat mesilate with oxaliplatin targeting NF-κB activation for pancreatic cancer

In this study, we assessed if nafamostat mesilate may enhance anti-tumor effects of oxaliplatin on Panc-1 cells and pancreatic cancer mouse model. In combination treatment with nafamostat mesilate and oxaliplatin, NF-κB activation was inhibited by suppressing IκBα phosphorylation, and caspase-8-mediated apoptosis was more prominent than that treated with oxaliplatin alone, both in vitro and in vivo. Nafamostat mesilate reduced proliferation rate of Panc-1 cells as compared with oxaliplatin alone in vitro and enhanced oxaliplatin-induced tumor growth inhibition in vivo. Combination chemotherapy using nafamostat mesilate and oxaliplatin induces synergistic cytotoxicity in pancreatic cancer and could be a novel strategy for treatment.

A Novel MIF Signaling Pathway Drives the Malignant Character of Pancreatic Cancer by Targeting NR3C2

Pancreatic cancers with aberrant expression of macrophage migration inhibitory factor (MIF) are particularly aggressive. To identify key signaling pathways that drive disease aggressiveness in tumors with high MIF expression, we analyzed the expression of coding and noncoding genes in high and low MIF-expressing tumors in multiple cohorts of pancreatic ductal adenocarcinoma (PDAC) patients. The key genes and pathways identified were linked to patient survival and were mechanistically, functionally, and clinically characterized using cell lines, a genetically engineered mouse model, and PDAC patient cohorts. Here, we report evidence of a novel MIF-driven signaling pathway that inhibits the orphan nuclear receptor NR3C2, a previously undescribed tumor suppressor that impacts aggressiveness and survival in PDAC. Mechanistically, MIF upregulated miR-301b that targeted NR3C2 and suppressed its expression. PDAC tumors expressing high levels of MIF displayed elevated levels of miR-301b and reduced levels of NR3C2. In addition, reduced levels of NR3C2 expression correlated with poorer survival in multiple independent cohorts of PDAC patients. Functional analysis showed that NR3C2 inhibited epithelial-to-mesenchymal transition and enhanced sensitivity to the gemcitabine, a chemotherapeutic drug used in PDAC standard of care. Furthermore, genetic deletion of MIF disrupted a MIF-mir-301b-NR3C2 signaling axis, reducing metastasis and prolonging survival in a genetically engineered mouse model of PDAC. Taken together, our results offer a preclinical proof of principle for candidate therapies to target a newly described MIF-miR-301b-NR3C2 signaling axis for PDAC management. Cancer Res; 76(13); 3838-50. ©2016 AACR.

Intrahepatic Cholangiocarcinoma Mimicking Hepatic Inflammatory Pseudotumor

A 50-year-old male with hepatitis B was referred for a small intrahepatic nodule. Magnetic resonance images raised strong suspicion of a benign lesion, such as an inflammatory pseudotumor, while the other radiological studies were equivocal. Furthermore, the high-intensity image on diffusion magnified-weighted imaging with a low B value strongly suggested a benign tumor. In spite of the absence of typical clinical or radiological findings, needle biopsy revealed an intrahepatic cholangiocarcinoma (ICC). The diagnosis of peripheral ICC rich in fibrous tissue seems to require needle biopsy for pathological examination with immunohistochemical staining because it frequently mimics other diseases, including benign tumors.

Inhibition of Nuclear Factor Kappa-B Enhances the Antitumor Effect of Combination Treatment with Tumor Necrosis Factor-Alpha Gene Therapy and Gemcitabine for Pancreatic Cancer in Mice

BACKGROUND Combination therapy with tumor necrosis factor-alpha (TNF-α) gene delivery and gemcitabine is a new therapeutic approach for pancreatic cancer. However, the efficacy of both TNF-α and gemcitabine is suppressed due to activation of nuclear factor-kappa B (NF-κB). We hypothesized that nafamostat mesilate (FUT175), an NF-κB inhibitor, enhances the antitumor effect of combination treatment with an adenoviral vector-expressing TNF-α (AxCAhTNF-α) and gemcitabine for pancreatic cancer in mice. STUDY DESIGN In vitro, we assessed that FUT175 inhibited both TNF-α- and gemcitabine-induced NF-κB activation and enhanced apoptosis in human pancreatic cancer cell lines (MIAPaCa-2 and AsPC-1). In vivo, we established a xenograft pancreatic cancer model in mice by subcutaneous injection of MIAPaCa-2 and AsPC-1. The animals were treated with AxCAhTNF-α intratumorally and gemcitabine intraperitoneally once a week (combination group) or AxCAhTNF-α intratumorally and gemcitabine intraperitoneally once a week as well as FUT175 intraperitoneally 3 times a week (triple combination group). RESULTS In vitro, FUT175 inhibited both TNF-α- and gemcitabine-induced NF-κB activation and enhanced induction of apoptosis. In the triple combination group, tumor growth in vivo was significantly slower and there were more apoptotic cells than in the combination group (p < 0.05). CONCLUSIONS Inhibition of NF-κB by FUT175 enhances the antitumor effect of combined TNF-α gene therapy and gemcitabine for pancreatic cancer.

Combination treatment using adenovirus vector-mediated tumor necrosis factor-alpha gene transfer and a NF-κB inhibitor for pancreatic cancer in mice

Gene therapy using an adenoviral vector expressing tumor necrosis factor-alpha (TNF-α) is a new therapeutic approach for pancreatic cancer. However, the efficacy of TNF-α is limited, because it activates nuclear factor-κB (NF-κB). We investigated the combined use of AxCAhTNF-α, adenoviral vector-expressing human TNF-α, and nafamostat mesilate, a serine-protease inhibitor, a NF-κB inhibitor, using pancreatic cancer in mice. In vitro, nafamostat mesilate inhibited TNF-α-induced NF-κB activation and enhanced TNF-α-induced apoptosis in human cancer cell line (MIAPaCa-2). In vivo, we assessed combination treatment of AxCAhTNF-α and nafamostat mesilate using xenograft models in nude mice by subcutaneous injection of MIAPaCa-2. When the implanted tumor size reached 8.0mm, TNF-α group (n=12), was injected AxCAhTNF-α intra-tumorally once a week, while combination group (n=12), was injected AxCAhTNF-α intra-tumorally once a week and nafamostat mesilate intraperitoneally thrice a week. In combination group, tumor growth was significantly slower, and the number of apoptosis cells was significantly greater than those in AxCAhTNF-α group (p<0.05). In conclusion, adenovirus vector-mediated TNF-α gene therapy combined with nafamostat mesilate was effective for pancreatic cancer in mice.

Hydroxyurea decreases gemcitabine resistance in pancreatic carcinoma cells with highly expressed ribonucleotide reductase.

Objectives This study aimed to determine whether the treatment of pancreatic carcinoma can be defined on the basis of the expression of genes involved in gemcitabine metabolism and whether combination treatment is more effective than conventional treatment. Methods Four pancreatic carcinoma cell lines (Panc-1, MIAPaCa-2, BxPC-3, and Capan-2) were used to determine the patterns of gemcitabine-metabolizing genes and mesenchymal marker gene expressions using quantitative real-time polymerase chain reaction. Chemosensitivity and cell proliferation were measured using colorimetric assay. Gemcitabine was combined with hydroxyurea or small interfering RNA targeting ribonucleotide reductase to assess changes in chemoresistance. Results Panc-1 and MIAPaCa-2 cell lines were profoundly chemoresistant and expressed genes corresponding to cells with distinct mesenchymal phenotypes. In addition, Panc-1 highly expressed ribonucleotide reductase and showed a 4-fold increase in gemcitabine sensitivity after treatment with hydroxyurea. Conclusions Combination treatment tailored to cells with highly expressed ribonucleotide reductase was more effective than treatment with gemcitabine alone. Moreover, phenotype and gemcitabine metabolism may independently confer chemoresistance. Abbreviations RR - ribonucleotide reductase, CDA - cytidine deaminase, dCK - deoxycytidine kinase

Combination paclitaxel and inhibitor of nuclear factor κB activation improves therapeutic outcome for model mice with peritoneal dissemination of pancreatic cancer.

Objectives: Paclitaxel (PTX) is a useful treatment for peritoneal dissemination of malignant tumors. However, chemoresistance due to PTX-induced nuclear factor &kgr;B (NF-&kgr;B) activation is an important cause of suboptimal therapeutic effect. We previously reported nafamostat mesilate (FUT175) inhibits NF-&kgr;B activation and promotes apoptosis in pancreatic cancer. We hypothesized that addition of FUT175 to PTX may enhance the antitumor effect in peritoneal dissemination of pancreatic cancer. Methods: In vitro, we assessed NF-&kgr;B activity and apoptosis by the combination of FUT175 and PTX using human pancreatic cancer cell line (AsPc-1). In vivo, we established peritoneal dissemination in nude mice by intraperitoneal injection of AsPc-1 cells. The animals were treated with intraperitoneal injection thrice a week of FUT175, once a week of PTX, or a combination of thrice a week of FUT175 and once a week of PTX (combination group). Results: In the combination groups, PTX-induced NF-&kgr;B activation was inhibited, and apoptosis was enhanced in comparison with other groups both in vitro and in vivo. In the combination group, tumor growth, serum tumor marker, and survival rate were significantly better than those in other groups (P < 0.05). Conclusions: Combination chemotherapy using PTX with FUT175 exerts an antitumor effect for peritoneal dissemination of pancreatic cancer.

Effect of NF-κB inhibition on chemoresistance in biliary–pancreatic cancer

Biliary cancer and pancreatic cancer are considered to be difficult diseases to cure. Although complete resection provides the only means of curing these cancers, the rate of resectability is not high. Therefore, chemotherapy is often selected in patients with advanced unresectable biliary–pancreatic cancer. Many combination chemotherapy regimens have been applied in clinical trials. However, the survival time is not satisfactory. On the other hand, most chemotherapeutic agents induce anti-apoptotic transcriptional factor nuclear factor kappa b (NF-κB) activation, and agent-induced NF-κB activation is deeply involved in the onset of chemoresistance. Recently, novel approaches to potentiating chemosensitivity in cases of biliary–pancreatic cancer using NF-κB inhibitors with cytotoxic agents have been reported, most of which comprise translational research, although some clinical trials have also been conducted. Nevertheless, to date, there is no breakthrough chemotherapy regimen for these diseases. As some reports show promising data, combination chemotherapy consisting of a NF-κB inhibitor with chemotherapeutic agents seems to improve chemosensitivity and prolong the survival time of biliary–pancreatic cancer patients.

Successful treatment of advanced gallbladder cancer with an anticancer drug S-1: assessment based on intratumoral gene

While surgical resection is the most effective treatment for gallbladder cancer, most of these cancers are not resectable at the time of diagnosis, and therefore, chemotherapy serves as the primary therapy in many cases. However, to date, there is no standard chemotherapy for this cancer. We report a case of advanced gallbladder cancer for which the anticancer drug S-1 was effective. The patient was a 53-year-old woman who presented with a huge ovarian tumor. On workup, all abdominal images revealed the presence of advanced gallbladder cancer that had invaded the liver. Because the gallbladder formed a relatively hard and swollen mass involving the omentum, as revealed during exploration, the surgical resection of the gallbladder was not possible at that time, and only hysterectomy and bilateral salpingo-oophorectomy were performed. She started on the anticancer drug S-1 just after this operation. S-1 is a prodrug of 5-fluorouracil (5-FU), and contains 5-chloro-2-4-dihydroxypyridine (CDHP), an inhibitor of dihydropyrimidine dehydrogenase (DPD) that rapidly degrades 5-FU. Eight months after the first operation, radical cholecystectomy was performed. Pathologically, the tumor was diagnosed as an adenocarcinoma of the gallbladder, and no evidence of liver invasion was found. Intratumoral gene expression analysis of the resected gallbladder revealed significantly elevated DPD expression. We suggest that the rapid degradation of 5-FU mediated by this high DPD in our patient was significantly blocked by the CDHP in S-1, and that the efficacy of 5-FU was consequently maintained at the maximum level.