Sachiko Matsuda

Abstract 1321: A novel prevention method against re-obstruction of titanium alloy stent for biliary malignancy using generation of hydroxyl radical under ultrasonic irradiation

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL [introduction] Palliative biliary drainage using a metallic stent is performed for biliary obstruction by unresectable biliary carcinoma.The most important problem of biliary stenting therapy is re-obstruction due to tumor ingrowth. The generation of hydroxyl radical was investigated during ultrasonic irradiation and in the presence of TiO2(Shimizu, etal.Ultrason.Sonochem.2008).The metal stent which is used for biliary drainage is made of titanium alloy, and it is thought that it could generate hydroxyl radicals under ultrasonic irradiation in the same way. The object of this study was to establish a novel prevention method of re-obstruction of the stent using generation of hydroxyl radical under ultrasonic irradiation. [method] {in vitro}Nickel titanium alloy was ultrasonically irradiated at frequency of 1MHz for 30 seconds and the amount of generated hydroxyl radical was measured when intensity was changed to 0.1-0.5 W/cm2 by APF method. To evaluate the cytotoxic effect of the generated radicals, trypan blue exclusion assay was used.The number of living cells were counted. {in vivo}A stent re-obstruction model was established.Nude mice(BALB c nu/nu) were given an injection of 1.0×107 of human squamous carcinoma A431 cells on the back.After Seven days, a stent was put in the neighborhood of tumor.The irradiation group(n=3) was given 10 minutes-ultrasonic irradiation of 0.3W /cm2 once a day.The non-irradiation group(n=3) was not irradiated. Tumors with stents were resected on the 14th day. Tumor ingrowth area was measured and histlogical examination of the tumors was performed. [result] {in vitro}The maximum amount of hydroxyl radical generation was measured under ultrasonic irradiation of 0.3W /cm2. The number of living cells with titanium alloy under ultrasonic irradiation(0.3W /cm2 30seconds) was 79% of that without ultrasonic irradiation. {in vivo}On the 14th day, tumor ingrowth to the stent was seen in the non-irradiation group of the stent re-obstruction model.Tumor ingrowth to the stent was clearly inhibited in the irradiation group. [conclusion] Hydroxyl radical was generated from a titanium alloy stent by ultrasonic irradiation and seemed to have therapeutic efficacy. Tumor ingrowth was inhibited, and preventive effect against re-obstruction was suggested. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1321. doi:1538-7445.AM2012-1321

Clinical significance of plasma fibrinogen level as a predictive marker for postoperative recurrence of esophageal squamous cell carcinoma in patients receiving neoadjuvant treatment.

Among multidisciplinary therapies developed for advanced esophageal cancer, neoadjuvant chemotherapy and chemoradiotherapy have been established as standard treatments. To deliver cautious follow up and intense treatment for high-risk patients, a simple and instructive biomarker for the postoperative recurrence needs to be identified. Fibrinogen, a common component of hemostasis, has been suggested to not only play an important role in cancer metastasis, but also correlate with tumor recurrence. We aim to clarify the validity of plasma fibrinogen as a marker for predicting the postoperative recurrence of esophageal squamous cell carcinoma patients who received neoadjuvant treatment. We reviewed 72 consecutive patients with esophageal squamous cell carcinoma who received neoadjuvant chemotherapy or chemoradiotherapy, followed by esophagectomy at the Keio University Hospital from 2001 to 2010. Of them, we retrospectively examined 68 patients who underwent plasma fibrinogen examination before and after neoadjuvant treatment and underwent transthoracic radical esophagectomy. We investigated patient characteristics, clinicopathological factors, neoadjuvant treatment effects, postoperative course, and plasma fibrinogen levels. We investigated pretreatment and preoperative (postneoadjuvant treatment) plasma fibrinogen levels, as well as changes in fibrinogen levels before and after neoadjuvant treatment. Patients with preoperative hyperfibrinogenemia (>350 mg/dL) and patients with increased plasma fibrinogen levels during neoadjuvant treatment showed significantly shorter postoperative disease-free survival (DFS) (P = 0.002 and P = 0.037, respectively). Moreover, we classified these patients into three classes on the basis of their preoperative fibrinogen levels and changes in fibrinogen levels during neoadjuvant treatment. Patients who had both high preoperative plasma fibrinogen and increased fibrinogen levels showed significantly shorter DFS than others. In contrast, patients who had normal preoperative plasma fibrinogen and decreased fibrinogen levels showed significantly longer DFS. Based on this fibrinogen classification, we could differentiate between significantly favorable and poor prognosis patients group. Overall, this classification (hazard ratio = 1.812, P = 0.013) and the response to neoadjuvant treatment (hazard ratio = 0.350, P = 0.007) were found to be significant determining factors for postoperative DFS. With the validity of preoperative plasma fibrinogen levels and changes in fibrinogen levels during neoadjuvant treatment, the plasma fibrinogen level was found to be a possible biomarker for postoperative recurrence in advanced esophageal cancer patients who received neoadjuvant treatment. Moreover, plasma fibrinogen classification could be a simple and valuable predictive marker for postoperative follow up.

Increased plasma levels of high mobility group box 1 in patients with acute liver failure

Background: High-mobility group box 1 (HMGB1) is a monocyte-derived late-acting inflammatory mediator, which is released in conditions such as shock, tissue injury and endotoxin-induced lethality. In this study, we determined the plasma and hepatic tissue levels of HMGB1 in patients with acute liver failure (ALF). Patients and Methods: We determined the plasma levels of HMGB1 and aspartate aminotransferase (AST) in 7 healthy volunteers (HVs), 40 patients with liver cirrhosis (LC), 37 patients with chronic hepatitis (CH), 18 patients with severe acute hepatitis (AH), and 14 patients with fulminant hepatitis (FH). The 14 patients with FH were divided into two subgroups depending upon the history of plasma exchange (PE) before their plasma sample collection. The hepatic levels of HMGB1 were measured in tissue samples from 3 patients with FH who underwent living-donor liver transplantation and from 3 healthy living donors. Hepatic tissue samples were also subjected to immunohistochemical examination for HMGB1. Results: The plasma levels of HMGB1 (ng/ml) were higher in patients with liver diseases, especially in FH patients with no history of PE, than in HVs (0.3 ± 0.3 in HVs, 4.0 ± 2.0 in LC, 5.2 ± 2.6 in CH, 8.6 ± 4.8 in severe AH, 7.8 ± 2.7 in FH with a history of PE, and 12.5 ± 2.6 in FH with no history of PE, p < 0.05 in each comparison). There was a strong and statistically significant relationship between the mean plasma HMGB1 level and the logarithm of the mean AST level (R = 0.900, p < 0.05). The hepatic tissue levels of HMGB1 (ng/mg tissue protein) were lower in patients with FH than in healthy donors (539 ± 116 in FH vs. 874 ± 81 in healthy donors, p < 0.05). Immunohistochemical staining for HMGB1 was strong and clear in the nuclei of hepatocytes in liver sections from healthy donors, but little staining in either nuclei or cytoplasm was evident in specimens from patients with FH. Conclusion: We confirmed that plasma HMGB1 levels were increased in patients with ALF. Based on a comparison between HMGB1 contents in normal and ALF livers, it is very likely that HMGB1 is released from injured liver tissue.

Neutrophil elastase inhibitor improves survival rate after ischemia reperfusion injury caused by supravisceral aortic clamping in rats

BACKGROUND Sivelestat sodium hydrate is a specific neutrophil elastase inhibitor effective in acute lung injury (ALI) associated with systemic inflammatory response syndrome. Bowel ischemia reperfusion injury (IRI) induced by supravisceral aortic clamping is associated with an excessive systemic inflammatory response, resulting in remote organ damage, including ALI. In this study, we investigated whether sivelestat can attenuate neutrophil sequestration in the lung, alleviate ALI, and improve survival in a rat bowel IRI model. METHODS Adult male Sprague-Dawley rats underwent bowel IRI induced by supravisceral aortic clamping and were randomly assigned to receive sivelestat or saline (control) and monitored for survival. We randomly assigned other rats to undergo laparotomy alone (sham operation), IRI alone, or IRI and sivelestat treatment. We evaluated blood samples for organ function, cytokine levels, and neutrophil elastase activity after reperfusion. Organs were analyzed histologically. We also determined lung injury in another set of rats. RESULTS Bowel IRI induced a significant increase in serum variables indicative of organ function, cytokine concentrations, neutrophil elastase activity, and lung permeability and edema, which reflected the presence of both systemic inflammatory response syndrome and compensatory anti-inflammatory response syndrome. Treatment with sivelestat significantly improved survival rate, lung permeability and edema, and significantly decreased levels of creatinine, interleukin 6, interleukin 10, and neutrophil elastase activity. Histological studies showed that sivelestat-treated rats had less bowel IRI-induced damage to lung and liver tissue than controls. CONCLUSION In a rat model, administration of sivelestat attenuated the effects of bowel IRI induced by supravisceral aortic clamping, and improved the survival rate.

Magnetically Promoted Rapid Immunoreactions Using Functionalized Fluorescent Magnetic Beads: A Proof of Principle

BACKGROUND Accurate detection and monitoring of disease-related biomarkers is important in understanding pathophysiology. We devised a rapid immunoreaction system that uses submicrometer polymer-coated fluorescent ferrite (FF) beads containing both ferrites (magnetic iron oxide) and fluorescent europium complexes. METHODS FF beads were prepared by encapsulation of hydrophobic europium complexes into the polymer layers of affinity magnetic beads using organic solvent. A sandwich immunoassay using magnetic collection of antibody-coated FF beads to a specific place was performed. Brain natriuretic peptide and prostate-specific antigen were selected as target detection antigens to demonstrate the feasibility of this approach. An immunohistochemical staining using magnetic collection of antibody-coated FF beads onto carcinoma cell samples was also performed. RESULTS The sandwich immunoassays, taking advantage of the magnetic collection of antibody-coated FF beads, detected target antigens within 5 min of sample addition. Without magnetic collection, the sandwich immunoassay using antibody-coated FF beads required long times, similar to conventional immunoassays. Using the magnetic collection of antibody-coated FF beads, immunohistochemical staining enabled discrimination of carcinoma cells within 20 min. CONCLUSIONS This proof of principle system demonstrates that immunoreactions involving the magnetic collection of antibody-coated FF beads allow acceleration of the antigen-antibody reaction. The simple magnetic collection of antibody-coated FF beads to a specific space enables rapid detection of disease-related biomarkers and identification of carcinoma cells.

Photodynamic Therapy Using an Anti-EGF Receptor Antibody Complexed with Verteporfin Nanoparticles: A Proof of Concept Study

Photodynamic therapy (PDT) is a noninvasive optical treatment method in which the topical or systemic delivery of photosensitizing drugs is followed by irradiation with broadband red light. Coupling photosensitizers with a specific antibody may allow this approach to target specific cancers. This study determines the antitumor efficacy of coupling verteporfin (Visudyne(®)), a hydrophobic polyporphryin oligomer, with an antiepidermal growth factor receptor (anti-EGFR) antibody. Poly[2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate-co-p-nitrophenylcarbonyloxyethyl methacrylate] (PMBN) was conjugated with an anti-EGFR antibody and mixed with verteporfin (verteporfin-PMBN-antibody complex). Tumor-bearing mice were intravenously injected with the verteporfin-PMBN-antibody complex or verteporfin plus PMBN without the antibody. Irradiation was conducted at 640 nm with a dose of 75 J/cm(2). The fluorescence intensity in A431 cells in vitro was threefold higher after exposure to verteporfin-PMBN-antibody complex than after exposure to verteporfin-PMBN. In A431 tumor-bearing mice, the intratumor concentration of verteporfin was 9.4 times higher than that of the skin, following administration of the verteporfin-PMBN-antibody complex. Tumor size significantly decreased within 8 days in mice treated with verteporfin-PMBN-antibody complex compared with those treated with verteporfin-PMBN. PDT using a PMBN-verteporfin-antibody complex offers a promising anticancer therapy.

Potent in vitro and in vivo antitumor activity of interleukin-4-conjugated Pseudomonas exotoxin against human biliary tract carcinoma

Targeting cytotoxins or immunotoxins to tumor cell surface receptors represents a new approach for the treatment of cancers. We tested the antitumor activity of a cytotoxin (IL‐4‐PE) composed of an interleukin‐4 (IL‐4) targeting moiety and a truncated form of Pseudomonas exotoxin A against human biliary tract carcinoma (BTC). Immunohistochemical analysis showed that cultured BTC cell lines and cancerous epithelia in BTC tissue (e.g., gallbladder carcinoma, extraheaptic cholangiocarcinoma, and intrahepatic cholangiocarcinoma) expressed receptors for IL‐4 in situ at high densities. However, normal epithelial cells in gallbladder and bile duct tissues did not express these IL‐4 receptors. Eight BTC cell lines expressed IL‐4R on the cell surface as determined by radiolabeled ligand binding assays. When these cells were treated with IL‐4‐PE, significant cytotoxicity was observed as determined by the inhibition of protein synthesis. The concentration of agent causing 50% inhibition of protein synthesis (IC50) was found to be less than 10 ng/mL in 4 of the 8 BTC cell lines studied. The antitumor activity of IL‐4‐PE was assessed for human BTC cells implanted subcutaneously in immunodeficient mice. By intratumoral injection of IL‐4‐PE, complete disappearance of the established tumors was observed in 40% of animals. Intraperitoneal administration of IL‐4‐PE at tolerated doses to animals with peritoneally disseminated BTC exhibited significantly prolonged survival compared to untreated animals (>14 weeks vs. 5 weeks in treated and untreated mice, respectively). These results indicate that IL‐4 receptor‐targeted cytotoxin is a potent agent that may provide a new therapeutic option for BTC.

In vivo identification of sentinel lymph nodes using MRI and size-controlled and monodispersed magnetite nanoparticles.

To develop a sentinel lymph node (SN) identification method using accurately synthesized magnetic nanoparticles (MNPs), as an enhanced specific SN tracer in combination with magnetic resonance imaging (MRI) in intact rodent and SN metastasis models.

Differential pathological response to preoperative chemotherapy across breast cancer intrinsic subtypes

Background: Breast cancer is a heterogeneous disease with a diversity of clinical behaviors. The purpose of this study was to evaluate the utility of breast cancer intrinsic subtypes in the prediction of pathological complete response (pCR) in a cohort of breast cancer patients receiving preoperative chemotherapy. Methods: Patients with stage II/III breast cancer received 4 cycles of XT (capecitabine and docetaxel) followed by 4 cycles of FEC (fluorouracil, epirubicin, and cyclophosphamide) as preoperative chemotherapy. Tumors were classified as luminal A, luminal B, luminal/HER2, HER2, basal-like, or non-basal-like triple negative by immunohistochemical analysis in core needle biopsy samples at baseline. Results: The overall pCR rate was 11.9% (12/101). Multivariate analysis showed that intrinsic subtype was an independent factor to predict pCR. With luminal A patients as the reference group, luminal B (OR = 16.39; 95% CI 1.44–185.88; p = 0.024), HER2 (OR = 14.73; 95% CI 1.19–180.84; p = 0.035), and basal-like (OR = 13.27; 95% CI 1.27–138.79; p = 0.031) patients had a significantly higher likelihood of pCR. Conclusion: The present data indicate that intrinsic subtypes may be useful predictive biomarkers of pCR in breast cancer patients treated with preoperative chemotherapy.

KRAS mutations in cell-free DNA from preoperative and postoperative sera as a pancreatic cancer marker: a retrospective study

Background:Pancreatic ductal adenocarcinoma (PDAC) has very poor prognosis despite existing multimodal therapies. This study aimed to investigate whether KRAS mutations at codons 12/13 in cell-free DNA (cfDNA) from preoperative and postoperative sera from patients with PDAC can serve as a predictive biomarker for treatment response and outcomes after surgery.Methods:Preoperative and postoperative serum samples obtained from 45 patients with PDAC whom underwent curative pancreatectomy at our institution between January 2013 and July 2016 were retrospectively analysed. Peptide nucleic acid-directed PCR clamping was used to identify KRAS mutations in cfDNA.Results:Among the 45 patients enrolled, 11 (24.4%) and 20 (44.4%) had KRAS mutations in cfDNA from preoperative and postoperative sera, respectively. Multivariate analysis revealed that KRAS mutations in postoperative serum (hazard ratio (HR)=2.919; 95% confidence interval (CI)=1.109–5.621; P=0.027) are an independent prognostic factor for disease-free survival. Furthermore, the shift from wild-type KRAS in preoperative to mutant KRAS in postoperative cfDNA (HR=9.419; 95% Cl=2.015–44.036; P=0.004) was an independent prognostic factor for overall survival.Conclusions:Changes in KRAS mutation status between preoperative and postoperative cfDNA may be a useful predictive biomarker for survival and treatment response.