Establishment of a patient-derived xenograft mouse model of pleomorphic leiomyosarcoma

Soft tissue sarcomas are difficult to treat using chemotherapy owing to a current deficiency in candidate drugs for specific targets. Screening candidate compounds and analyzing therapeutic targets in sarcomas is insufficient, given the lack of an appropriate human sarcoma animal model to accurately evaluate their efficacy, as well as the lack of an adequate technical protocol for efficient transplantation and engraftment of sarcoma specimens in patient-derived xenograft (PDX) models. Accordingly, in this study, we sought to identify the optimal type of sarcoma and develop a protocol for generating a PDX model. We characterized a PDX mouse model using histopathological and immunohistochemical analyses to determine whether it would show pathological characteristics similar to those of human sarcomas. We achieved engraftment of one of the 10 transplanted sarcoma specimens, the xenografted tumor of which exhibited massive proliferation. Histologically, the engrafted sarcoma foci resembled a primary tumor of pleomorphic leiomyosarcoma and maintained their histological structure in all passages. Moreover, immunohistochemical analysis revealed the expression of specific markers of differentiation to smooth muscle, which is consistent with the features of leiomyosarcoma. We thus demonstrated that our pleomorphic leiomyosarcoma PDX mouse model mimics at least one aspect of human sarcomas, and we believe that this model will facilitate the development of novel therapies for sarcomas.

An improved mouse orthotopic bladder cancer model exhibiting progression and treatment response characteristics of human recurrent bladder cancer

Nonmuscle-invasive (superficial) bladder cancer is generally treated via surgical removal, followed by adjuvant therapy (bacillus Calmette-Guerin). However, bladder cancer can often recur, and in a substantial number of recurrent cases, the cancer progresses and metastasizes. Furthermore, residual microtumors following excision may lead to an increased risk of recurrence. An in vivo model mimicking the pattern of urinary bladder microtumor regrowth may provide an effective experimental system for improving postsurgical treatment outcomes. A mouse bladder cancer model established using orthotopic transplant of UM-UC-3 human urinary bladder carcinoma cells has been established, however, to the best of our knowledge, no report has investigated sequential histological changes, including early-phase changes and treatment responses in bladder cancer. In the present study, the efficiency of the model was optimized and the sequential changes were examined using histopathology and in situ imaging. The therapeutic effects of cisplatin (CDDP) and gemcitabine (GEM) were also examined, which are drugs that are often used for follow-up chemotherapy. Tumor-seeding efficiency reached 90-100%, with muscle layer and bladder lumen invasion occurring in ~21 days, using the following modifications: i) Shallow catheter insertion to mitigate bladder wall damage; ii) bladder pretreatment using prewarmed trypsin, followed by light urethral clamping and body temperature maintenance for more efficient removal of transitional epithelium; and iii) seeding with UM-UC-3 cells (rather than HT1376, 5637 or T24 tumor cells) in a medium supplemented with Matrigel. Transplant with UM-UC-3 cells resulted in isolated microlesions that progressed into tumors, invading the bladder lumen and muscle layer to the serosal surface. Tumor growth was markedly reduced by weekly intravenous injections of CDDP and partially suppressed by GEM. Therefore, this model is reliable, and pathological progression and treatment responses recapitulate the features of recurrent human bladder cancer.

Modulation of methotrexate-induced intestinal mucosal injury by dietary factors

Methotrexate (MTX)-induced intestinal mucosal injury in animals has been studied to understand how MTX can cause gastrointestinal disorders, but the pathogenesis of gastrointestinal disorders is still uncertain. We have attempted to reveal how dietary factors influence intestinal toxicity due to MTX. Mice were fed normal chow (NC) or a high-fat high-sucrose diet (HFHSD) before oral administration of MTX. While MTX significantly decreased the survival rates of mice fed HFHSD, the intestinal epithelial injury was detected. MTX excretion in the feces of mice fed HFHSD was reduced. Change of diets between NC and HFHSD influences the survival. The survival rates of the mice fed a high-sucrose diet or control diet were higher than those fed HFHSD. Higher survival rates were observed in mice fed a high-fat high-sucrose diet modified (HFHSD-M) in which casein was replaced by soybean-derived proteins. The survival rates of mice treated with vancomycin were lower than those administered neomycin. Microbiome and metabolome analyses on feces suggest a similarity of the intestinal environments of mice fed NC and HFHSD-M. HFHSD may modify MTX-induced toxicity in intestinal epithelia on account of an altered MTX distribution as a result of change in the intestinal environment.

P4678The hemodynamic improvement with balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension depends on the lesion location

Background

Pulmonary endarterectomy (PEA) is a treatment of choice for patients with chronic thromboembolic pulmonary hypertension (CTEPH). Patients with proximal pulmonary artery disease are considered to be good candidates for PEA because of their generally excellent outcomes. However, not all patients can be operated because of patients' advanced age, comorbidities and poor general condition. Balloon pulmonary angioplasty (BPA) has become an alternative treatment for CTEPH patients especially whose lesions locate in the distal site. The effectiveness of BPA in patients who have lesions in the proximal pulmonary arteries but cannot be a candidate for PEA remains unclear.

Purpose

The aim of this study was to investigate the outcome of BPA in CTEPH patients whose lesions appears operable but ineligible for PEA.

Methods

A total of 370 patients who underwent BPA in our institute from November 2004 to January 2018 were enrolled. All the patients were divided into operable group and inoperable group according to the difference of lesion location based on the findings of perfusion scintigraphy, computed tomography and pulmonary angiography. Hemodynamic effects of BPA in both groups were investigated. We also conducted survival analyses using the Kaplan-Meier method with the log-rank test.

Results

Among 370 patients, 90 patients deemed operable. The main reasons why not operated in the PEA operable group were patient's refusal (44%), advanced age (14%), and comorbidities (27%). There were no baseline characteristic differences between two groups except for the history of acute pulmonary embolism. Mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) equally improved after BPA in both groups (operable: 38.2±10.8 mmHg to 21.5±4.7mmHg, inoperable: 42.4±11.3 mmHg to 21.8±4.8 mmHg, p<0.001, operable: 8.0±4.2 wood unit to 3.5±1.5 wood unit, inoperable: 9.1±4.6 wood unit to 3.4±1.3 wood unit, p<0.001). Furthermore, five-year cumulative survival rates were not different between two groups (inoperable vs. operable: 93% vs. 88%, p=0.23, median follow-up period was 23.0 months (range: 5–136 months)). Meanwhile, the absolute change of mPAP and PVR in inoperable group were greater than those in operable group (inoperable: 20.7±11.2 mmHg, operable: 16.6±11.0 mmHg, p=0.010, inoperable: 5.6±4.4 wood unit, operable: 4.5±3.9 wood unit, p=0.015).

Conclusions

Although the outcome of BPA for CTEPH patients with operable lesions appears acceptable, absolute change in hemodynamics was lower than that of the patients with inoperable lesions. CTEPH with proximal lesions should be treated with PEA rather than BPA.

P4675The utility of additional balloon pulmonary angioplasty for residual hypoxemia in normohemodynamic chronic thromboembolic pulmonary hypertension patients after invasive treatments

Background

Balloon pulmonary angioplasty (BPA) improves hemodynamics, symptoms and exercise capacity in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are ineligible for pulmonary endarterectomy (PEA). However, certain patients still have hypoxemia after BPA or PEA despite normalization of hemodynamics. In CTEPH, hypoxemia is related increased dead space ventilation caused by vascular obstruction.

Purpose

This study was aimed to clarify whether additional BPA can improve hypoxemia of CTEPH patients after normalization of hemodynamics.

Methods

A total of 335 patients who underwent initial series of BPA in our institute were followed up. Sixty-four patients with mean pulmonary artery pressure (mPAP) <30mmHg and percutaneous oxygen saturation (SpO2) <95% without oxygen inhalation at more than 6 months after the initial series of BPA and of patients who could reevaluate hemodynamics and oxygenation after additional BPA were enrolled. These patients were divided into two groups with or without additional BPA procedures. Change of hemodynamics and SpO2 were retrospectively investigated.

Results

Thirty-three of 64 patients underwent additional BPA procedures. Patients' age was older in BPA group than those in non-BPA group (71.3±10.4 vs. 66.5±9.4 years old, p=0.02). mPAP and pulmonary vascular resistance (PVR) was significantly higher in BPA group (mPAP: 23.9±3.2 vs. 20.7±3.8 mmHg, p=0.001, PVR: 4.2±1.2 vs. 3.5±1.4 wood unit, p=0.03, respectively). Among the 1.8±1.4 BPA procedures per person, total 6.6±3.8 segmental pulmonary arteries per person were treated. While no obvious improvements were observed in non-BPA group, PVR and SpO2 in BPA group were significantly improved (4.2±1.2 to 3.7±1.3 wood unit, p=0.002, 90.7±3.1% to 94.1±3.6%, p<0.001, respectively). In the multivariate logistic regression analysis, additional BPA procedures were associated with further improvement of SpO2 (hazard ratio, 3.7; 95% confidence interval, 1.2–11.5; P=0.02).

Conclusions

Additional BPA procedure was associated with improvement of hypoxemia in CTEPH patients after normalization of hemodynamics. Treating as many lesions as possible in BPA might relieve the patients' residual dyspnea.

FF-10832 enables long survival via effective gemcitabine accumulation in a lethal murine peritoneal dissemination model

Chemotherapy has been the treatment of choice for unresectable peritoneal dissemination; however, it is difficult to eradicate such tumors because of poor drug delivery. To solve this issue, we developed FF‐10832 as liposome‐encapsulated gemcitabine to maintain a high concentration of gemcitabine in peritoneal tumors from the circulation and ascites. A syngeneic mouse model of peritoneal dissemination using murine Colon26 cell line was selected to compare the drug efficacy and pharmacokinetics of FF‐10832 with those of gemcitabine. Despite the single intravenous administration, FF‐10832 treatment enabled long‐term survival of the lethal model mice as compared with those treated with gemcitabine. Pharmacokinetic analysis clarified that FF‐10832 could achieve a more effective gemcitabine delivery to peritoneal tumors owing to better stability in the circulation and ascites. The novel liposome‐encapsulated gemcitabine FF‐10832 may be a curative therapeutic tool for cancer patients with unresectable peritoneal dissemination via the effective delivery of gemcitabine to target tumors.

Factors associated with a positive willingness to practise oral health care in the future amongst oral healthcare and nursing students

OBJECTIVES

The purpose of this study was to identify the weak points in the knowledge and attitudes of first-year oral health care and nursing students towards oral health care and to identify the factors associated with their positive willingness to practise oral health care after becoming a health professional in order to develop oral healthcare curricula.

MATERIALS AND METHODS

The subjects were 88 first-year dental students (DSs), 64 dental hygiene students (DHSs) and 119 nursing students (NSs) enrolled in schools in Japan, as of April 2017. A questionnaire was distributed to subjects in each school to assess their knowledge and attitudes towards oral health care.

RESULTS

Less than half knew that oral health care was also provided in cancer hospitals, hospices, acute care hospitals, maternity wards and psychiatric wards. Only 46.2% knew that oral health care was effective in the prevention of aspiration pneumonia. The level of knowledge and attitudes in NSs regarding oral health care were likely to be lowest amongst the student groups. Only NSs' high interest towards oral health care was associated with their positive willingness to practise oral health care in the future although oral health students' high perceptions and interest regarding oral health care were associated with the willingness.

CONCLUSION

This study showed oral healthcare and nursing students' weak points regarding their attitudes and knowledge of oral health care at early stages. Oral health academic staff and professionals should develop effective oral healthcare curricula for oral healthcare students and help nursing staff develop a collaborative nursing oral healthcare curriculum to motivate nursing students.

Dedifferentiated retroperitoneal liposarcoma spontaneously occurring in an aged SD rat

Liposarcoma is a rare neoplasm in rats and is characterized by the presence of lipoblasts containing multiple cytoplasmic vacuoles. We encountered a rare type of liposarcoma in a male SD (Crj:CD(SD)IGS) rat during a long-term study to gather background data. At necropsy at 105 weeks of age, there was a large amount of fatty tissue covering the mesentery, pancreas, and retroperitoneum; a white nodule in the right kidney; and paleness of the liver. Microscopically, the tumor had a well-differentiated component and dedifferentiated high-grade component. Immunohistochemical and electron microscopic examinations revealed that the pleomorphic tumor cells retained the characteristics of lipoblasts. Distant or disseminated metastasis was also confirmed in various organs. A liposarcoma with these histological features is extremely rare in rats, and this is the first report of a highly metastatic dedifferentiated type of liposarcoma originating from the abdominal fat tissue in a rat.

Endogenous protein and enzyme fragments induce immunoglobulin E-independent activation of mast cells via a G protein-coupled receptor, MRGPRX2

Mast cells play a central role in inflammatory and allergic reactions by releasing inflammatory mediators through 2 main pathways, immunoglobulin E-dependent and E-independent activation. In the latter pathway, mast cells are activated by a diverse range of basic molecules (collectively known as basic secretagogues) through Mas-related G protein-coupled receptors (MRGPRs). In addition to the known basic secretagogues, here, we discovered several endogenous protein and enzyme fragments (such as chaperonin-10 fragment) that act as bioactive peptides and induce immunoglobulin E-independent mast cell activation via MRGPRX2 (previously known as MrgX2), leading to the degranulation of mast cells. We discuss the possibility that MRGPRX2 responds various as-yet-unidentified endogenous ligands that have specific characteristics, and propose that MRGPRX2 plays an important role in regulating inflammatory responses to endogenous harmful stimuli, such as protein breakdown products released from damaged or dying cells.

A Case of Antiphospholipid Antibody Syndrome Diagnosed after Thrombosis of an Arteriovenous Shunt

A 32-year-old male dialysis patient with lupus nephritis was admitted because of shunt obstruction. The arteriovenous fistula was reconstructed, but obstruction recurred twice within several hours after surgery. A high blood level of anticardiolipin β2-glycoprotein I antibody suggested that shunt obstruction was caused by a thrombotic tendency related to the antiphospholipid antibody syndrome. Accordingly, for the third shunt procedure, antiplatelet therapy (which had been commenced for systemic lupus erythematosus) was combined with dalteparin sodium from before surgery and warfarin was added postoperatively. This regimen prevented shunt obstruction. In conclusion, hemodialysis patients who suffer repeated shunt obstruction should be examined for antiphospholipid antibody syndrome.

Investigation into metastatic processes and the therapeutic effects of gemcitabine on human pancreatic cancer using an orthotopic SUIT-2 pancreatic cancer mouse model

Prognosis of pancreatic cancer is poor, thus the development of novel therapeutic drugs is necessary. During preclinical studies, appropriate models are essential for evaluating drug efficacy. The present study sought to determine the ideal pancreatic cancer mouse model for reliable preclinical testing. Such a model could accurately reflect human pancreatic cancer phenotypes and predict future clinical trial results. Systemic pathology analysis was performed in an orthotopic transplantation model to prepare model mice for use in preclinical studies, mimicking the progress of human pancreatic cancer. The location and the timing of inoculated cancer cell metastases, pathogenesis and cause of fatality were analyzed. Furthermore, the efficacy of gemcitabine, a key pancreatic cancer drug, was evaluated in this model where liver metastasis and peritoneal dissemination occur. Results indicated that the SUIT-2 orthotopic pancreatic cancer model was similar to the phenotypic sequential progression of human pancreatic cancer, with extra-pancreatic invasion, intra-peritoneal dissemination and other hematogenous organ metastases. Notably, survival was prolonged by administering gemcitabine to mice with metastasized pancreatic cancer. Furthermore, the detailed effects of gemcitabine on the primary tumor and metastatic tumor lesions were pathologically evaluated in mice. The present study indicated the model accurately depicted pancreatic cancer development and metastasis. Furthermore, the detailed effects of pancreatic cancer drugs on the primary tumor and on metastatic tumor lesions. We present this model as a potential new standard for new drug development in pancreatic cancer.

Isolation of new ligands for orphan receptor MRGPRX1-hemorphins LVV-H7 and VV-H7

The human MAS-related G protein-coupled receptor X1 (MRGPRX1) is a member of the GPCR family. The receptor is primate specific and expressed in the sensory neurons of dorsal root ganglion and trigeminal ganglion, where it is considered to be involved in the pain perception. The MRGPRX1 has unusual binding mechanism, as it is activated by several different ligands as well as several different fragments of precursor proteins. Thus, we hypothesize that it is activated by several unknown compounds as well since the receptor is still classified as orphan. Here, we describe the isolation of two novel endogenous ligands for the MRGPRX1 from human platelet preparation. The isolated ligands are hemoglobin β-chain fragments, known members of the hemorphin family.

The opinions and attitudes of dental school academic staff towards oral healthcare education for older adults

The term 'oral health care for older adults' has various interpretations, and its meaning is not clear among dental school academic staff. Additionally, there are no theoretical or practical stand-alone courses on oral health care for older adults in Japanese dental schools. To improve oral health care education, we investigated the opinions and attitudes toward oral health care education for older adults among academic staff in dental schools. Data were collected in seven dental schools from May to September 2013 via an online questionnaire survey. Five-hundred-fifty-eight academics (428 male, 130 female) participated (response rate 57%). The average number of years since they had completed a university degree was 20.2 (SD 10.2) years. The majority (Over 90%) of participants perceived that oral health care should be provided in nursing facilities, hospitals, and at home. Its treatments and instructions should include, not only methods of keeping good oral hygiene, but also improvement of oral function such as swallowing training and salivary glands massage. The majority (84.2%) suggested oral health care education should be combined as a one-credit, stand-alone course. Findings indicate that dental academics have an understanding the need for a course in oral health care for older adults. Participants supported the need for further development of education in oral health care for older adults' in Japan, as a separate course on its own right. However there were some different views about content by teaching field. The need for a national core program for teaching oral health care education was suggested.

Genomewide association study identifies HAS2 as a novel susceptibility gene for adult asthma in a Japanese population

BACKGROUND

It is increasingly clear that asthma is not a single disease, but a disorder with vast heterogeneity in pathogenesis, severity, and treatment response. To date, 30 genomewide association studies (GWASs) of asthma have been performed, including by our group. However, most gene variants identified so far confer relatively small increments in risk and explain only a small proportion of familial clustering.

OBJECTIVE

To identify additional genetic determinants of susceptibility to asthma using a selected Japanese population with reduced tobacco smoking exposure.

METHODS

We performed a GWAS by genotyping a total of 480 098 single-nucleotide polymorphisms (SNPs) for a Japanese cohort consisting of 734 healthy controls and 240 patients with asthma who had smoked for no more than 10 pack-years. The SNP with the strongest association was genotyped in two other independent Japanese cohorts consisting of a total of 531 healthy controls and 418 patients with asthma who had smoked for no more than 10 pack-years. For the hyaluronan synthase 2 (HAS2) gene, we investigated SNP-gene associations using an expression quantitative trait loci (eQTL) database and also analysed its gene expression profiles in 13 different normal tissues.

RESULTS

In the discovery GWAS, a SNP located upstream of HAS2, rs7846389, showed the strongest statistical significance (P = 1.43 × 10(-7) ). In the two independent replication cohorts, rs7846389 was consistently associated with asthma (nominal P = 0.0152 and 0.0478 in the first and second replication cohorts, respectively). In the meta-analysis, association of rs7846389 with susceptibility to asthma reached the level of genomewide significance (P = 7.92 × 10(-9) ). This variant was strongly correlated with HAS2 mRNA expression. The strongest expression of the gene was detected in the lung.

CONCLUSIONS

Our study identified HAS2 as a novel candidate gene for susceptibility to adult asthma.

Mutant allele frequency predicts the efficacy of EGFR-TKIs in lung adenocarcinoma harboring the L858R mutation

BACKGROUND

Whether the mutant allele frequency (MAF) may also have predictive implications for tyrosine kinase inhibitor (TKI) therapy in patients with advanced epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma (AELAd) remains unknown.

PATIENTS AND METHODS

Based on a biobanking system in conjunction with our institution, we assessed EGFR mutation status using pyrosequencing (Py) and by outsourcing laboratory tests, such as the Cycleave (Cy) and the Scorpion ARMS (A).

RESULTS

Out of 705 patients enrolled in the Shizuoka Lung Cancer Mutation Study between July 2011 and March 2013, 102 AELAd patients were identified as carrying the L858R mutation (L858Rm) using Py to analyze histological specimens. Of these 102 patients, the EGFR mutation status was assessed using both Py and Cy in 48 patients: the median MAF of L858R (MAFLR) was 18.5% (range: 8%-82%), and 45 patients (94%) were identified as having an L858Rm using both Py and Cy. Three patients (6%) with discrepant L858Rm findings were only identified using Py. The plotting of a receiver operating characteristic curve to identify the discordance in L858Rm findings showed that the area under the curve for MAFLR was 0.967 (95% confidence interval: 0.91-1) and that an MAFLR of 9% resulted in high sensitivity (100%) and specificity (99%). Also, 29 patients with AELAd, excluding those with postoperative recurrences, had their L858R status assessed using Cy or A. The median age, 69 years (range: 47-84 years); male/female, 14 (48%)/15 (52%); smokers/never-smokers 13 (45%)/16 (55%); ECOG PS 0-1/2-3, 26 (90%)/3 (10%); stage IIIB/IV, 4 (14%)/25 (86%); median MAFLR, 18% (range: 8%-63%). Patients with an MAFLR of ≤9% had a significantly shorter progression-free survival (PFS) period after TKI therapy than those with an MAFLR of >9% (mPFS: 92 versus 284 days, P = 0.0027).

CONCLUSION

The MAF may be a potential predictive factor of TKI treatment efficacy in patients with AELAd carrying the L858Rm.

Apomictic parthenogenesis in a parasitoid wasp Meteorus pulchricornis, uncommon in the haplodiploid order Hymenoptera

Although apomixis is the most common form of parthenogenesis in diplodiploid arthropods, it is uncommon in the haplodiploid insect order Hymenoptera. We found a new type of spontaneous apomixis in the Hymenoptera, completely lacking meiosis and the expulsion of polar bodies in egg maturation division, on the thelytokous strain of a parasitoid wasp Meteorus pulchricornis (Wesmael) (Braconidae, Euphorinae) on pest lepidopteran larvae Spodoptera litura (Fabricius) (Noctuidae). The absence of the meiotic process was consistent with a non-segregation pattern in the offspring of heterozygous females, and no positive evidence was obtained for the induction of thelytoky by any bacterial symbionts. We discuss the conditions that enable the occurrence of such rare cases of apomictic thelytoky in the Hymenoptera, suggesting the significance of fixed heterosis caused by hybridization or polyploidization, symbiosis with bacterial agents, and occasional sex. Our finding will encourage further genetic studies on parasitoid wasps to use asexual lines more wisely for biological control.

Experimental validation of a novel compact focusing scheme for future energy-frontier linear lepton colliders

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.