Abstract 195: CD44v9 expression in clinical pancreatic cancer and the gemcitabine plus sulfasalazine therapy against chemoresistant pancreatic cancer murine model

Objective: Chemoresistance associating CD44-positive cancer stem cells may presents a crucial problem in treating pancreatic cancer. Among the various isoforms of CD44, valiant 9 (CD44v9) have revealed especially implicated in tumor growth, invasion, and metastasis. Interaction of CD44v9 with the cystine transporter subunit xCT provide the ability of cancer cells to defend themselves against reactive oxygen species, mediating chemoresistance. Sulfasalazine (SSZ), which is a specific inhibitor of xCT-mediated cystine transport,could be a new therapeutic weapon fight against cancer stem cells.

However, the extent of this remains unclear, suggesting the need for a histological evaluation of CD44v9 expression in clinical pancreatic cancer and the anti-tumor effect on pancreatic cancer of SSZ. Therefore,

In this study, we analyze the expression of CD44v9 in a pancreatic cancer surgical specimen and examine the anti-tumor effect of SSZ and altered expression of CD44v9 by administration of GEM (GEM) with tumorgrafts.

Methods:

Experiment 1: A total of 70 clinical primary ductal adenocarcinoma of the pancreas were applied for immunohistochemical evaluation of CD44v9 expression. Randomly picked up 10 fields for each cases were analyzed for intensity of membrane staining and the percentage of stained cancer cells per field, followed by summing the scores using our own scoring system.

Experiment 2: Three lines of created tumorgrafts from clinical pancreatic cancer. We administered GEM to the tumorgrafts and also scored the clinical specimens’ immunohistochemical evaluation by CD44v9. In addition, using one line, we divided the mice into two groups, a GEM group and a GEM + SSZ group, and repeated as above to determine the effect on GEM of SSZ.

Results:

Experiment 1: There was no correlation for prognosis. It was found that CD44v9-positive cells are present in high numbers.

Experiment 2: In 1 line, which increased CD44v9-positive cell after GEM treatment,the GEM group showed tumor regression of 85% and the GEM+SSZ group showed tumor regression of 90%.

Discussion: Result in Experiment 1 is reasonable, therefore, to consider the significance of the treatment target CD44vv9 as likely to be very high. Further, there was one line of tumorgrafts used, but not all percentages of CD44v9-positive cells increased markedly by GEM administration. This suggests the possibility that CD44v9 may be regarded as a marker of GEM resistance. In addition, a small but insignificant tumor regression effect on GEM of SSZ was found.

We present evidence that for pancreatic cancer as well as other carcinomas, CD44v9-positive cells may be regarded as one of the markers of chemo resistance. Furthermore, since SSZ shows the antitumor effects of plus for GEM, we suggest that SSZ treatment is a possibility for a new treatment option.

Citation Format: Tomohiro Kurokawa, Tatsuya Oda, Yuki Inagaki, Ryoichi Miyamoto, Yoshimasa Akashi, Nobuhiro Ohkohchi. CD44v9 expression in clinical pancreatic cancer and the gemcitabine plus sulfasalazine therapy against chemoresistant pancreatic cancer murine model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 195. doi:10.1158/1538-7445.AM2014-195

Abstract 171: Adipose-derived mesenchymal stem cell (ADSC) has the differentiation capacity toward cancer associated fibroblast (CAF) and reproduce the morphology of the clinical tumor stroma

[Objectives] Crosstalk between cancer cells and Cancer-Associated Fibroblast (CAF) plays a crucial role that comprises 3D organization of solid cancers. It seems general understanding that the main origin of CAF is circulating bone marrow derived Mesenchymal Stem Cell (BM-MSC), though locally pre-existing resident MSC of adipose tissue (AD-MSC) should partly contribute to CAF formation. The role of CAF and MSC to tumorigenesis remains controversial,since some studies reported cancer stimulating effect by externally added MSC or its potential differentiating into CAF, while others showed its suppressive effect. The capability of MSC's innate tropism for cancer, which enables us to apply it for the cellular delivery of anti-cancer molecules, has attracted much attention. One of the key issues should be whether externally added MSC would accepted as a member of cancer 3D organization, and would contribute to the cancer morphology. We tried to reveal whether AD-MSC, which is much convenient source as engineered MSC than BM-MSC, stimulates or inhibit tumor growth, and how MSC contribute to tumor stromal morphogenesis.

[Materials & Methods]

Experiment: To evaluate the growth advantage by adding MSC, and how MSC contribute to tumor stromal morphogenesis, two differently-originated ADSC cell lines transfected with GFP was mixed with human pancreatic-cancer cell line (Capan-1) at a rate of 3×106 /5×106 , and inoculated into the back subcutaneous resion of BALB/cAJcl-nu/nu mice. The tumor volume was calculated at Day4, Day7 and Day10 to assess the growth advantage of tumor mixed with ADSC. The mice was sacrificed at Day 10 and the histology of the resected tumor was evaluated with fluorescence microscopy and immunostaining procedure with anti-GFP antibody.

[Results]

Capan-1 formed significantly larger subcutaneous tumor by adding with both two AD-MSC cell lines(352mm3,265mm3) compared to control (70mm3) at Day10. In the tumor mixed with one ADSC cell line, cancer cells formed ductal stractures and contained fiber rich stroma with GFP positive fibroblasts among cancer ducts, mimicked the similar distribution to that in clinical solid cancer specimen. However, in the graft with the other ADSC cell line, cancer cells presented cord-like structures or deregulated cell proliferation, not formed ductal stractures. Though GFP positive cells could be observed, they thinly and rondamly distributed in the stroma.

[Discussion]

Both two AD-MSC plays promotive role in tumor growth, and one of which strongly contribute to the tumor stromal morphogenesis. Our AD-MSC could be regarded as a case which obviously differentiated into CAF, and would be a good candidate source for forecomming CAF therapy. Further studies revealing CAFs specific signature would helpful for providing stable AD-MSC source.

Citation Format: Yuki Inagaki, Tatsuya Oda, Tomohiro Kurokawa, Ryoichi Miyamoto, Yasuyuki Kida, Nobuhiro Ohkohchi. Adipose-derived mesenchymal stem cell (ADSC) has the differentiation capacity toward cancer associated fibroblast (CAF) and reproduce the morphology of the clinical tumor stroma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 171. doi:10.1158/1538-7445.AM2014-171

Abstract 2663: Hyperthermia improves Cetuximab accumulation in pancreatic cancer mouse model

Objective:

Histopathological characteristics of pancreatic carcinoma are the presence of abundant stroma that prevent mAb diffusion and consequently hampers mAb from direct attacking cancer cells. With a strong conviction that additional tool that improve mAb penetration and diffusion in dense fibroblastic solid cancer should indispensable for better therapeutic effect, we focused and employed the simple but strongest modalities, heat. Heat might increase tumor blood flow and tumor vessel permeability, leading enhanced accumulation of anticancer mAb.

In this study, we aimed the increased accumulation of mAb in mouse pancreatic subcutaneous models and also boosted antitumor effects by applying moderate heat.

Methods:

Heat generation was completed by hot bathtub method for subcutaneous tumor in nude mice leg. Three human pancreatic cell of different stromal amount were employed (abundant: Capan-1, moderate: BxPC-3, and scant: MIAPaCa-2). At the timing of each tumors growth up to 70mm3, Cetuximab (1 mg/kg) was systematically administrated via caudal vein, subsequently applying heat to tumors for 30 min at three different temperatures of 25°C (control temperature), 37°C (intraabdominal organs), or 41°C (hyperthermia) (n = 5 each). The amount of accumulated Cetuximab were quantified by the fluorescent intensity of Alexa 488 against anti-human IgG at 24 hr, followed by figuring up the intensity of one cancer cell by dividing the total intensity value by the number of a cancer cell nuclei stained with DAPI. Enhanced antitumor effects, among irradiating various heat doses, were evaluated by the tumor volume over time.

Results:

In Capan-1, the fluorescent intensity per a cancer cell at 25°C, 37°C, 41°C were 675, 1130, 2332 respectively. Similarly, those in BxPC-3 were 673, 1347, 1573, and in MIAPaCa-2 were 1632, 1921, 1949, respectively.

In Capan-1 and BxPC-3, the mean tumor growth on day 40 were significantly inhibited at 37°C group (934, 189 mm3), and 41°C group (491, 121 mm3) in compared with 25°C group (1385, 470 mm3) respectively.

In MIAPaCa-2, however, that on day 50 was not inhibited at 37 degrees group (109 mm3), and 41 group (151 mm3) as compared with 25 group (123 mm3).

Discussion:

We demonstrated that hyperthermia actually contributed to measurable add-on antitumor effect for two among three pancreatic cancer models. Intending to provide more add-on effect, we are now evaluating the combined effects of hyperthermia plus applying a cyclic tumor-penetrating peptide (iRGD), which improved anticancer mAb penetration to cancer cells by binding to integrin αv/β3 or β5 and to neuropillin-1 on cancer cells. We suggested that this novel combined strategy would remarkably contribute to the enhanced accumulation of anticancer mAb in tumors and to the enhanced antitumor effects.

Citation Format: Ryoichi Miyamoto, Tatsuya Oda, Shinji Hashimoto, Yoshimasa Akashi, Tomohiro Kurokawa, Yuki Inagaki, Nobuhiro Ohkohchi. Hyperthermia improves Cetuximab accumulation in pancreatic cancer mouse model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2663. doi:10.1158/1538-7445.AM2014-2663

Three-dimensional imaging identified the accessory bile duct in a patient with cholangiocarcinoma

The development of diagnostic imaging technology, such as multidetector computed tomography (MDCT) and magnetic resonance cholangiopancreatography (MRCP), has made it possible to obtain detailed images of the bile duct. Recent reports have indicated that a 3-dimensional (3D) reconstructed imaging system would be useful for understanding the liver anatomy before surgery. We have investigated a novel method that fuses MDCT and MRCP images. This novel system easily made it possible to detect the anatomical relationship between the vessels and bile duct in the portal hepatis. In this report, we describe a very rare case of extrahepatic cholangiocarcinoma associated with an accessory bile duct from the caudate lobe connecting with the intrapancreatic bile duct. We were unable to preoperatively detect this accessory bile duct using MDCT and MRCP. However, prior to the second operation, we were able to clearly visualise the injured accessory bile duct using our novel 3D imaging modality. In this report, we suggest that this imaging technique can be considered a novel and useful modality for understanding the anatomy of the portal hepatis, including the hilar bile duct.

Measurement of intravenously administered γ-Fe2O3 particle amount in mice tissues using vibrating sample magnetometer

Dispersions of platelet γ-Fe2O3 particles 30-50nm in size were intravenously administered to mice and the amount of particles accumulated in each tissue was obtained by magnetization measurement using a vibrating sample magnetometer. Background noise was greatly reduced by measuring dried tissues under a magnetic field of 500 Oe so that the effect of diamagnetism was slight. Remarkable particle accumulation was observed in the liver and spleen. Considerable particle accumulation was observed in the lung when a large quantity of γ-Fe2 O3 particles was administered. There was no significant particle accumulation in the kidney and heart.

Anticancer effects of gemcitabine are enhanced by co-administered iRGD peptide in murine pancreatic cancer models that overexpressed neuropilin-1

BACKGROUND

Impaired drug transport is an important factor that reduces the efficacy of anticancer agents against pancreatic cancer. Here, we report a novel combination chemotherapy using gemcitabine (GEM) and internalised-RGD (iRGD) peptide, which enhances tumour-specific drug penetration by binding neuropilin-1 (NRP1) receptor.

METHODS

A total of five pancreatic cancer murine models (two cell line-based xenografts (CXs) and three tumour grafts (TGs)) were treated with either GEM (100 mg kg(-1), q3d × 4) alone or GEM plus iRGD peptide (8 μmol kg(-1)). Evaluation of NRP1 expression in xenografts and 48 clinical cancer specimens was performed by immunohistochemistry (IHC).

RESULTS

We identified a subset of pancreatic cancer models that showed NRP1 overexpression sensitive to iRGD co-administration. Treatment with GEM plus iRGD peptide resulted in a significant tumour reduction compared with GEM monotherapy in CXs, but not remarkable in TGs. Potential targets of iRGD were characterised as cases showing NRP1 overexpression (IHC-2+/3+), and these accounted for 45.8% of the clinical specimens.

CONCLUSIONS

Internalised RGD peptide enhances the effects of co-administered drugs in pancreatic cancer models, its efficacy is however only appreciable in those employing cell lines. Therefore, the clinical application needs to be given careful consideration.

Histological and prognostic importance of CD44(+) /CD24(+) /EpCAM(+) expression in clinical pancreatic cancer

CD44(+) /CD24(+) /EpCAM(+) cells have been reported to be cancer stem cells in pancreatic cancer; however, the histological and clinical importance of these cells has not yet been investigated. Here we clarified the characteristics of CD44(+) /CD24(+) /EpCAM(+) cells in clinical specimens of pancreatic cancer using immunohistochemical assay. We used surgical specimens of pancreatic ductal adenocarcinoma from 101 patients. In view of tumor heterogeneity, we randomly selected 10 high-power fields per case, and triple-positive CD44(+) /CD24(+) /EpCAM(+) expression was identified using our scoring system. The distribution, histological characteristics, and prognostic importance of CD44(+) /CD24(+) /EpCAM(+) cells were then analyzed. As a result, the distribution of CD44(+) /CD24(+) /EpCAM(+) cells varied widely among the 101 cases examined, and CD44(+) /CD24(+) /EpCAM(+) expression was correlated with poor glandular differentiation and high proliferation. Survival analysis showed that CD44(+) /CD24(+) /EpCAM(+) expression was not correlated with patient outcome; however, CD44(+) /CD24(+) expression appeared to be correlated with poor prognosis. In conclusion, CD44(+) /CD24(+) /EpCAM(+) expression overlapped with poorly differentiated cells and possessed high proliferative potential in clinical pancreatic cancer. In particular, the presence of double-positive CD44(+) /CD24(+) expression seemed to have clinical relevance, associating with poor prognosis.

Abstract OT1-1-01: A phase II study of neoadjuvant epirubicin/cyclophosphamide (EC) followed by weekly nanoparticle albumin-bound paclitaxel with or without trastuzumab for node-positive breast cancer

Background: Paclitaxel is considered standard treatment for metastatic breast cancer (MBC) and is often used as adjuvant and neoadjuvant chemotherapy for patients with early-stage disease. Conventional paclitaxel requires solvents such as polyoxyethylated castor oil; however, such solvents are associated with toxicity including peripheral neuropathy and hypersensitivity reaction. Moreover, the use of the drug requires special tubing and in-line filters. Therefore, nanoparticle albumin-bound paclitaxel (nab-PTX) requiring no solvent has been developed. Nab-PTX was effective in patients with MBC and as a neoadjuvant therapy. A comparison between weekly and triweekly nab-PTX suggested that weekly nab-PTX was superior in progression-free survival.

Trial design: This is a phase II trial to evaluate the efficacy and toxicity of neoadjuvant epirubicin/cyclophosphamide (EC) (epirubicin/cyclophosphamide) followed by weekly nab-PTX with or without trastuzumab for node-positive breast cancer. Patients receive four cycles of epirubicin (90 mg/m2) and cyclophosphamide (600 mg/m2) every 3 weeks, followed by four cycles of nab-PTX (125 mg/m2) on days 1, 8 and 15 in a 28-day cycle. Fifteen cycles of trastuzumab (2 mg/kg, loading 4 mg/kg) are added to the nab-PTX regimen in HER2-positive patients every week.

Eligibility criteria: Patients with histologically diagnosed invasive breast cancer based on a core needle biopsy of the T1-4 N1-3 without previous operation or chemotherapy are included in this trial. Eligible patients are aged between 20 years and 70 years with a performance status of 0 to 2 and adequate organ functions.

Specific aims: The primary endpoint is the pathologic complete response (pCR) rate in the breast and axilla, and the secondary endpoints are the breast conserving rate, toxicities, feasibility and overall survival.

Statistical methods: The sample size was calculated using the Simon method, with a type I error of 10% and a study power of 80%. 1. HER2-negative patients

The expected rate of pCR was 25% and the required number of patients was estimated to be 33. 2. HER2-positive patients

The expected rate of pCR was 50%, and the required number of patients was estimated to be 21.

Present and target accrual: Patient accrual within two medical centers started in April 2011 with 20 patients being on study to date (2012, June 12). A total of 56 patients (22 are HER2-positive and 34 are HER2-negative) are planned to be enrolled in the trial.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT1-1-01.

Decrease of blood dendritic cells and increase of tissue-infiltrating dendritic cells are involved in the induction of Sjögren's syndrome but not in the maintenance

We have demonstrated previously that, in primary Sjögren's syndrome (SS), immature myeloid dendritic cells (DCs) are decreased in blood and mature myeloid DCs are accumulated in salivary glands, suggesting recruitment of the myeloid DCs from blood to salivary glands. To verify whether this finding is universal in patients of not only primary SS but also secondary SS, in this study we analysed the blood DCs of secondary SS patients. We examined 24 secondary SS and 29 primary SS patients. A direct correlation between the decreased number of myeloid DCs and the duration of Sicca syndrome in primary and secondary SS was observed; namely, the reduction of myeloid DCs in blood was restored spontaneously with duration time of Sicca syndrome. We also examined the immunohistochemical staining of salivary glands of SS patients with monoclonal antibodies against fascin, CD11c and human leucocyte antigen DR (HLA-DR). Fascin(+) or CD11c(+)/HLA-DR(+) mononuclear cells were present in the salivary glands of secondary SS patients, as in primary SS. However, fascin(+) mononuclear cells were barely detected in the salivary glands of a chronic phase of SS patients. We also found a negative correlation between the frequency of blood myeloid DCs and salivary gland-infiltrating DCs in secondary SS patients, as well as primary SS. Our results suggest that the reduction of blood myeloid DCs and preferential trafficking of myeloid DCs into salivary glands is a common event in the early stage of SS. Myeloid DCs may play essential roles in the pathogenesis of Sicca syndrome of SS by initiating T helper cell immune responses.

Purification and comparison of triosephosphate isomerases from ammonia-oxidizing bacteria isolated from terrestrial and marine environments

Triosephosphate isomerases [TIMs, EC 5.3.1.1] were purified from two ammonia-oxidizing bacteria: Nitrosomonas sp. K1 (K1), Nitrosomonas sp. TNO632 (TNO). The molecular masses of the native enzymes were estimated to be about 53.6 (K1-TIM) and 51.9 kDa (TNO-TIM) by gel filtration, whereas SDS-PAGE produced one band for each enzyme with M(r) values of 27.1 (K1-TIM) and 26.4 kDa (TNO-TIM), respectively, suggesting that the enzymes consist of identical subunits. The apparent K(m) for d-glyceraldehyde-3-phosphate (GAP) and dihydroxyacetone phosphate (DHAP) were about 1.19 and 4.78 mM (K1-TIM), and 0.41 and 6.01 mM (TNO-TIM), respectively. The two TIMs had different pH-activity curves with an optimum pH range of 6.5 (K1-TIM) and 8.0 (TNO-TIM). The temperature optima of K1-TIM and TNO-TIM were 50-60 and 60-65 degrees C, respectively. Both enzymes were strongly inhibited by 5,5'-ditiobis at 1.0 mM. The N-terminal amino acid sequences of K1-TIM and TNO-TIM were MRAGFVAGNWKMHG (K1-TIM) and MVRTGLVAGNWKMNG (TNO-TIM). A homology of 74.1% was observed between K1-TIM and TNO-TIM.

[A clinical investigation of oro-maxillary sinus-perforation due to tooth extraction]

Oro-maxillary sinus perforation occurs occasionally at the extraction of a maxillary tooth, and it may be a cause of maxillary sinusitis or antro-oral fistula. Our purpose was to investigate the most frequent site of perforation, and to understand the clinical course of patients after perforation. We examined 2,038 maxillary teeth extracted from 1,337 patients (473 males and 864 females) at the First Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, from January 1991 to December 1993. Perforation occurred in 77 of all 2,038 teeth (3.8%). Of these, 38 teeth were from males (38/733; 5.2%), and 39 were from females (39/1,305; 3.0%). The perforation rate was significantly higher in males. Perforation occurred most often with extraction of an upper first molar, and in the third decade of life. The perforation rate gradually decreased with higher age. We classified 38 cases into 3 categories according to panorama X-P: 1) The tip of the root crossed over the bottom line of the maxillary sinus (29 cases), 2) Not crossed over distinctly (4 cases), 3) Just lie on, or whether the tip of the root crossed over the bottom line of the maxillary sinus was not distinct (5 cases). As to treatment, 30 perforations (39.0%) closed spontaneously in the course of observation, irrigation with physiological saline was used in 43 cases (55.8%), radical sinusotomy accompanied by closure of the perforation was performed in 4 cases, and only flap closure was used in 7 cases. There were no cases of relapse.

Cumulative effect of family environment on psychiatric symptomatology among multiethnic adolescents

PURPOSE

To examine the influence of family adversity and support on levels of psychiatric symptomatology in Hawaiian and non-Hawaiian adolescents.

METHOD

More than 4000 students from five high schools in Hawaii completed a survey during the 1992-1993 school year about their family environment and mental health. The response rate was approximately 60%. Logistic regression analyses were performed and responses for Hawaiians and non-Hawaiians were compared.

RESULTS

Hawaiian adolescents experienced significantly more adversity than their non-Hawaiian counterparts. The cumulative effect of family adversity had a greater effect on psychiatric symptomatology than any single indicator. Family support reduced the risk for internalizing symptoms, particularly for Hawaiian adolescents. The influence of family support was less clear for externalizing symptoms, increasing the risk for some adolescents and decreasing the risk for others.

CONCLUSION

We identified strong associations between family adversity and levels of psychiatric symptomatology. We found that Hawaiian adolescents are at increased risk for psychiatric symptomatology, given the presence of family adversity and the effect of reduced family support. However, risk was also substantial for non-Hawaiians. Clinicians need to assess the family environment routinely and implement family-oriented interventions.

Tol1, a fission yeast phosphomonoesterase, is an in vivo target of lithium, and its deletion leads to sulfite auxotrophy

Lithium is the drug of choice for the treatment of bipolar affective disorder. The identification of an in vivo target of lithium in fission yeast as a model organism may help in the understanding of lithium therapy. For this purpose, we have isolated genes whose overexpression improved cell growth under high LiCl concentrations. Overexpression of tol1(+), one of the isolated genes, increased the tolerance of wild-type yeast cells for LiCl but not for NaCl. tol1(+) encodes a member of the lithium-sensitive phosphomonoesterase protein family, and it exerts dual enzymatic activities, 3'(2'),5'-bisphosphate nucleotidase and inositol polyphosphate 1-phosphatase. tol1(+) gene-disrupted cells required high concentrations of sulfite in the medium for growth. Consistently, sulfite repressed the sulfate assimilation pathway in fission yeast. However, tol1(+) gene-disrupted cells could not fully recover from their growth defect and abnormal morphology even when the medium was supplemented with sulfite, suggesting the possible implication of inositol polyphosphate 1-phosphatase activity for cell growth and morphology. Given the remarkable functional conservation of the lithium-sensitive dual-specificity phosphomonoesterase between fission yeast and higher-eukaryotic cells during evolution, it may represent a likely in vivo target of lithium action across many species.