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

Nafamostat mesylate attenuates the pathophysiologic sequelae of neurovascular ischemia

Nafamostat mesylate, an apparent soi-disant panacea of sorts, is widely used to anticoagulate patients undergoing hemodialysis or cardiopulmonary bypass, mitigate the inflammatory response in patients diagnosed with acute pancreatitis, and reverse the coagulopathy of patients experiencing the commonly preterminal disseminated intravascular coagulation in the Far East. The serine protease inhibitor nafamostat mesylate exhibits significant neuroprotective effects in the setting of neurovascular ischemia. Nafamostat mesylate generates neuroprotective effects by attenuating the enzymatic activity of serine proteases, neuroinflammatory signaling cascades, and the endoplasmic reticulum stress responses, downregulating excitotoxic transient receptor membrane channel subfamily 7 cationic currents, modulating the activity of intracellular signal transduction pathways, and supporting neuronal survival (brain-derived neurotrophic factor/TrkB/ERK1/2/CREB, nuclear factor kappa B. The effects collectively reduce neuronal necrosis and apoptosis and prevent ischemia mediated disruption of blood-brain barrier microarchitecture. Investigational clinical applications of these compounds may mitigate ischemic reperfusion injury in patients undergoing cardiac, hepatic, renal, or intestinal transplant, preventing allograft rejection, and treating solid organ malignancies. Neuroprotective effects mediated by nafamostat mesylate support the wise conduct of randomized prospective controlled trials in Western countries to evaluate the clinical utility of this compound.

The Molecular Aspect of Antitumor Effects of Protease Inhibitor Nafamostat Mesylate and Its Role in Potential Clinical Applications

Nafamostat mesylate (NM), a synthetic serine protease inhibitor first placed on the market by Japan Tobacco in 1986, has been approved to treat inflammatory-related diseases, such as pancreatitis. Recently, an increasing number of studies have highlighted the promising effects of NM in inhibiting cancer progression. Alone or in combination treatments, studies have shown that NM attenuates various malignant tumors, including pancreatic, colorectal, gastric, gallbladder, and hepatocellular cancers. In this review, based on several activating pathways, including the canonical Nuclear factor-κB (NF-κB) signaling pathway, tumor necrosis factor receptor-1 (TNFR1) signaling pathway, and tumorigenesis-related tryptase secreted by mast cells, we summarize the anticancer properties of NM in existing studies both in vitro and in vivo. In addition, the efficacy and side effects of NM in cancer patients are summarized in detail. To further clarify NM's antitumor activities, clinical trials devoted to validating the clinical applications and underlying mechanisms are needed in the future.

Glycogen synthase kinase-3β activity plays a key role in the antitumor effect of nafamostat mesilate in pancreatic cancer cells

Pancreatic cancer is often resistant to chemotherapy. We previously showed the efficacy of combination treatment using gemcitabine and nafamostat mesilate (FUT‐175) for patients with unresectable pancreatic cancer. However, the mechanisms that affect the sensitivity of FUT‐175 are not fully understood. The purpose of the present study was to clarify the mechanism of the sensitivity to FUT‐175, with a focus on the activity of glycogen synthase kinase‐3β (GSK‐3β). In vitro, we assessed sensitivity to FUT‐175 in human pancreatic cancer cell lines (PANC‐1 and MIAPaCa‐2) and difference of signaling in these cells by cell proliferation assay, Western blot analysis and microarray. Next, we assessed cell viability, apoptotic signal and nuclear factor‐kappa B (NF‐κB) activity in response to treatment with FUT‐175 alone and in combination with GSK‐3 inhibitor or protein phosphatase 2A (PP2A) by cell proliferation assay, Western blot analysis and enzyme‐linked immunosorbent assay. Phosphorylated GSK‐3β level was significantly higher in MIAPaCa‐2 (high sensitivity cell) than in PANC‐1 (low sensitivity cell). Cell viability and NF‐κB activity were significantly decreased by addition of GSK‐3 inhibitor to FUT‐175, and levels of cleaved caspase‐8 were increased by inhibition of GSK‐3. PP2A inhibitor increased the levels of phosphorylated GSK‐3β and sensitized both cell lines to FUT‐175 as measured by cell viability and apoptotic signal. The results indicate that GSK‐3β activity plays a key role in the antitumor effect of FUT‐175 in pancreatic cancer cells, and regulation of GSK‐3β by PP2A inhibition could be a novel therapeutic approach for pancreatic cancer.

Radical Resection of a Primarily Unresectable Pancreatic Cancer After Neoadjuvant Chemotherapy Using Gemcitabine, TS-1, and Nafamostat Mesilate; Report of a Case

A 58-year-old male visited his primary physician for epigastric and back pain. Abdominal-enhanced computed tomography (CT) revealed a hypovascular pancreatic tumor measuring 17 × 11 mm in the uncinate process of the pancreas extending into the superior mesenteric plexus for greater than 180°. With a diagnosis of unresectable pancreatic cancer, the patient received gemcitabine and TS-1 with arterial infusion of nafamostat mesilate. After 3 courses of chemotherapy, enhanced CT revealed a decrease in size of the pancreatic tumor with no lymph node and distant metastasis and improved invasion of the superior mesenteric plexus down to 120°. The patient underwent R0 pancreaticoduodenectomy. The patient made a satisfactory recovery without complications and was discharged on postoperative day 10. We herein report the first curative resected case of a primarily unresectable pancreatic cancer after neoadjuvant chemotherapy using gemcitabine, TS-1, and nafamostat mesilate.

Dual inhibition of nuclear factor kappa-B and Mdm2 enhance the antitumor effect of radiation therapy for pancreatic cancer

INTRODUCTION

Radiation therapy, alone or in combination with chemotherapy, is effective for patients with locally advanced and recurrent pancreatic cancer. Ionizing radiation induces cell cycle arrest and cell apoptosis through enhancement several signals such as p53, p21(Waf1/Cip1), and caspase. However, the therapeutic efficacy is attenuated by radiation-induced activation of NF-κB. Nafamostat mesilate, a synthetic serine protease inhibitor, inhibits NF-κB activation in pancreatic cancer. Therefore, we hypothesized that nafamostat mesilate inhibited radiation-induced activation of NF-κB and improves therapeutic outcome.

RESULTS

In combination group, NF-κB activation was significantly inhibited in comparison with that of radiation group. Nafamostat mesilate obviously down-regulated the expression levels of Mdm2 compared with control cells or irradiated cells. Consequently, p53 expression was stabilized inversely in correlation with Mdm2 protein expression level. The expression levels of p53, p21(Waf1/Cip1), cleaved caspase-3 and -8 were the highest in the combination group. Nafamostat mesilate enhanced ionizing radiation-induced cell apoptosis and G2/M cell cycle arrest. In combination group, cell proliferation and tumor growth were significantly slower than those in other groups.

CONCLUSION

Combination therapy of radiation with nafamostat mesilate exerts enhanced anti-tumor effect against human pancreatic cancer.

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.

Inhibition of nuclear factor-κB enhances the antitumor effect of paclitaxel against gastric cancer with peritoneal dissemination in mice

BACKGROUND

Intraperitoneal (i.p.) administration of paclitaxel is useful for treating malignant tumors with peritoneal dissemination, but the therapeutic efficacy is limited. Chemoresistance due to paclitaxel-induced nuclear factor-kappa B (NF-κB) activation is an important cause of suboptimal therapeutic efficacy.

AIMS

The purpose of this study was to prove that addition of nafamostat mesilate (FUT-175), a synthetic serine protease inhibitor and an NF-κB inhibitor, to i.p. paclitaxel enhances antitumor effects of paclitaxel against gastric cancer with peritoneal dissemination.

METHODS

In vitro, we assessed NF-κB activity and apoptosis in response to treatment with FUT-175 alone, paclitaxel alone, or a combination of FUT-175 and paclitaxel in a human gastric cancer cell line (MKN-45). In vivo, we established peritoneal dissemination in nude mice by i.p. injection of MKN-45 cells. The animals received i.p. injections of FUT-175 alone three times a week (FUT-175 group), of paclitaxel alone once a week (paclitaxel group), or a combination of FUT-175 and paclitaxel (combination group) three times and once a week, respectively.

RESULTS

In the combination group, paclitaxel-induced NF-κB activation was inhibited and apoptosis was enhanced in comparison with those in the other groups both in vitro and in vivo. In the combination group, number and weight of peritoneal nodules were significantly lower than those in the paclitaxel group (p = 0.0009 and p = 0.0417, respectively). In the survival analysis, the combination group had a significantly better survival than the paclitaxel group (p = 0.0048).

CONCLUSION

FUT-175 enhances the antitumor effect of i.p. paclitaxel against gastric cancer with peritoneal dissemination by inhibiting NF-κB activation in mice.

Swainsonine inhibits growth and potentiates the cytotoxic effect of paclitaxel in hepatocellular carcinoma in vitro and in vivo

Swainsonine, an extract from Astragalus membranaceus, exhibits broad inhibition of growth and pro-apoptotic activity in a number of tumor types. However, the underlying mechanism involved remains unclear. To investigate the effects and mechanisms of swainsonine on hepatocellular carcinoma (HCC), we performed experiments on HepG2, SMCC7721, Huh7 and MHCC97-H human hepatoma and HL-7702 human hepatocyte cells. We observed that swainsonine significantly inhibited the viability of human hepatoma cells in a dose- and time-dependent manner, but did not affect human hepatocytes. Due to their highly proliferative and tumorigenic nature, we selected MHCC97-H cells as a model system to examine. Swainsonine significantly inhibited MHCC97-H cell growth by causing cell cycle arrest at the G0/G1 phase and the induction of apoptosis. Blockage of G0/G1 phase was accompanied by a decrease in cyclins (D1 and E) and cyclin-dependent kinases (Cdk2 and Cdk4) and an increase in the Cdk inhibitors p21 and p27. Furthermore, swainsonine enhanced the apoptosis of MHCC97-H cells with the induction of the upregulation of Bax and the downregulation of Bcl-2, whereas the expressionof Fas and Fas-L remained almost unchanged. These changes were accompanied by the enhanced cytoplasmic accumulation of nuclear factor κB (NF-κB) with a concomitant decrease in the nuclear fraction. Importantly, swainsonine also potentiated the cytotoxic effects of paclitaxel in vitro and in vivo, in part, by restricting the paclitaxel-induced nuclear accumulation of NF-κB. Taken together, these results suggest that swainsonine may be an important agent against HCC via directly inhibiting HCC cell growth and enhancing the responsiveness of HCC cells to paclitaxel.