Engineering fibronectin-templated multi-component fibrillar extracellular matrices to modulate tissue-specific cell response

Cells assemble fibronectin, the major extracellular matrix (ECM) protein, into fibrillar matrices, which serve as 3D architectural scaffolds to provide, together with other ECM proteins tissue-specific environments. Although recent approaches enable to bioengineer 3D fibrillar fibronectin matrices in vitro, it remains elusive how fibronectin can be co-assembled with other ECM proteins into complex 3D fibrillar matrices that recapitulate tissue-specific compositions and cellular responses. Here, we introduce the engineering of fibrillar fibronectin-templated 3D matrices that can be complemented with other ECM proteins, including vitronectin, collagen, and laminin to resemble ECM architectures observed in vivo. For the co-assembly of different ECM proteins, we employed their innate fibrillogenic mechanisms including shear forces, pH-dependent electrostatic interactions, or specific binding domains. Through recapitulating various tissue-specific ECM compositions and morphologies, the large scale multi-composite 3D fibrillar ECM matrices can guide fibroblast adhesion, 3D fibroblast tissue formation, or tissue morphogenesis of epithelial cells. In other examples, we customize multi-composite 3D fibrillar matrices to support the growth of signal propagating neuronal networks and of human brain organoids. We envision that these 3D fibrillar ECM matrices can be tailored in scale and composition to modulate tissue-specific responses across various biological length scales and systems, and thus to advance manyfold studies of cell biological systems.

Aggregated chromosomes/chromatin transfer: a novel approach for mitochondrial replacement with minimal mitochondrial carryover: the implications of mouse experiments for human aggregated chromosome transfer

Nuclear transfer techniques, including spindle chromosome complex (SC) transfer and pronuclear transfer, have been employed to mitigate mitochondrial diseases. Nevertheless, the challenge of mitochondrial DNA (mtDNA) carryover remains unresolved. Previously, we introduced a method for aggregated chromosome (AC) transfer in human subjects, offering a potential solution. However, the subsequent rates of embryonic development have remained unexplored owing to legal limitations in Japan, and animal studies have been hindered by a lack of AC formation in other species. Building upon our success in generating ACs within mouse oocytes via utilization of the phosphodiesterase inhibitor 3-isobutyl 1-methylxanthine (IBMX), this study has established a mouse model for AC transfer. Subsequently, a comparative analysis of embryo development rates and mtDNA carryover between AC transfer and SC transfer was conducted. Additionally, the mitochondrial distribution around SC and AC structures was investigated, revealing that in oocytes at the metaphase II stage, the mitochondria exhibited a relatively concentrated arrangement around the spindle apparatus, while the distribution of mitochondria in AC-formed oocytes appeared to be independent of the AC position. The AC transfer approach produced a marked augmentation in rates of fertilization, embryo cleavage, and blastocyst formation, especially as compared to scenarios without AC transfer in IBMX-treated AC-formed oocytes. No significant disparities in fertilization and embryo development rates were observed between AC and SC transfers. However, relative real-time PCR analyses revealed that the mtDNA carryover for AC transfers was one-tenth and therefore significantly lower than that of SC transfers. This study successfully accomplished nuclear transfers with ACs in mouse oocytes, offering an insight into the potential of AC transfers as a solution to heteroplasmy-related challenges. These findings are promising in terms of future investigation with human oocytes, thus advancing AC transfer as an innovative approach in the field of human nuclear transfer methodology.

Inferring and perturbing cell fate regulomes in human brain organoids

Self-organizing neural organoids grown from pluripotent stem cells1-3 combined with single-cell genomic technologies provide opportunities to examine gene regulatory networks underlying human brain development. Here we acquire single-cell transcriptome and accessible chromatin data over a dense time course in human organoids covering neuroepithelial formation, patterning, brain regionalization and neurogenesis, and identify temporally dynamic and brain-region-specific regulatory regions. We developed Pando-a flexible framework that incorporates multi-omic data and predictions of transcription-factor-binding sites to infer a global gene regulatory network describing organoid development. We use pooled genetic perturbation with single-cell transcriptome readout to assess transcription factor requirement for cell fate and state regulation in organoids. We find that certain factors regulate the abundance of cell fates, whereas other factors affect neuronal cell states after differentiation. We show that the transcription factor GLI3 is required for cortical fate establishment in humans, recapitulating previous research performed in mammalian model systems. We measure transcriptome and chromatin accessibility in normal or GLI3-perturbed cells and identify two distinct GLI3 regulomes that are central to telencephalic fate decisions: one regulating dorsoventral patterning with HES4/5 as direct GLI3 targets, and one controlling ganglionic eminence diversification later in development. Together, we provide a framework for how human model systems and single-cell technologies can be leveraged to reconstruct human developmental biology.

N-acetylcysteine overcomes NF1 loss-driven resistance to PI3Kα inhibition in breast cancer

A genome-wide PiggyBac transposon-mediated screen and a resistance screen in a PIK3CA^H1047R-mutated murine tumor model reveal NF1 loss in mammary tumors resistant to the phosphatidylinositol 3-kinase α (PI3Kα)-selective inhibitor alpelisib. Depletion of NF1 in PIK3CA^H1047R breast cancer cell lines and a patient-derived organoid model shows that NF1 loss reduces sensitivity to PI3Kα inhibition and correlates with enhanced glycolysis and lower levels of reactive oxygen species (ROS). Unexpectedly, the antioxidant N-acetylcysteine (NAC) sensitizes NF1 knockout cells to PI3Kα inhibition and reverts their glycolytic phenotype. Global phospho-proteomics indicates that combination with NAC enhances the inhibitory effect of alpelisib on mTOR signaling. In public datasets of human breast cancer, we find that NF1 is frequently mutated and that such mutations are enriched in metastases, an indication for which use of PI3Kα inhibitors has been approved. Our results raise the attractive possibility of combining PI3Kα inhibition with NAC supplementation, especially in patients with drug-resistant metastases associated with NF1 loss.

A high-throughput drug screen reveals means to differentiate triple-negative breast cancer

Plasticity delineates cancer subtypes with more or less favourable outcomes. In breast cancer, the subtype triple-negative lacks expression of major differentiation markers, e.g., estrogen receptor α (ERα), and its high cellular plasticity results in greater aggressiveness and poorer prognosis than other subtypes. Whether plasticity itself represents a potential vulnerability of cancer cells is not clear. However, we show here that cancer cell plasticity can be exploited to differentiate triple-negative breast cancer (TNBC). Using a high-throughput imaging-based reporter drug screen with 9 501 compounds, we have identified three polo-like kinase 1 (PLK1) inhibitors as major inducers of ERα protein expression and downstream activity in TNBC cells. PLK1 inhibition upregulates a cell differentiation program characterized by increased DNA damage, mitotic arrest, and ultimately cell death. Furthermore, cells surviving PLK1 inhibition have decreased tumorigenic potential, and targeting PLK1 in already established tumours reduces tumour growth both in cell line- and patient-derived xenograft models. In addition, the upregulation of genes upon PLK1 inhibition correlates with their expression in normal breast tissue and with better overall survival in breast cancer patients. Our results indicate that differentiation therapy based on PLK1 inhibition is a potential alternative strategy to treat TNBC.

Renocardiac protective effects of SGLT2 inhibitor combined with angiotensin receptor blocker in salt sensitive Dahl rats

Background

Kidney plays a central role in regulating salt-sensitivity of blood pressure (BP) to governs sodium excretion via several mechanisms including pressure natriuresis and the actions of renal sodium transporters.

Purpose

We clarified the effects of combination treatment of sodium-glucose cotransporter 2 (SGLT2) inhibitor and angiotensin receptor blocker (ARB) on BP and the pathogenesis of renocardiac injuries, and elucidated underlying molecular mechanisms involved in the regulation of renal sodium handling in the development of salt-sensitivity by comparing with each monotreatment in Dahl salt-sensitive (DSS) hypertensive rats.

Methods

DSS rats were treated orally for 8-weeks with normal salt diet (0.3% NaCl) (NS/Cont group), high salt diet (8% NaCl) (HS/Cont group), high salt diet with ipragliflozin (0.04%) (HS/Ipra group), high salt diet with losartan (0.05%) (HS/Los group), or high salt diet with combination of ipragliflozin and losartan (HS/Ipra+Los group).

Results

The combination group significantly reduced systolic BP compared with either high salt diet control group, losartan or ipragliflozin monotreatment groups (HS/Ipra+Los: 182.5±18.4mmHg vs HS/Cont: 227.7±26.1; HS/Ipra: 216.6±26.9; HS/Los: 208.6±21.6, at 8-weeks of treatment, P<0.05, respectively) (Figure 1A). The slope of pressure-natriuresis curve was significantly increased in the HS/Ipra+Los group compared to that in the HS/Cont group (interaction P=0.024), HS/Ipra group (P=0.009), and HS/Los group (P=0.084) using the linear regression model (Figure 1B), which indicated that only the combination treatment of ipragliflozin and losartan improved salt-sensitivity. The combined treatment significantly improved creatinine clearance (HS/Ipra+Los: 3.3±0.9mL/min vs HS/Cont: 1.1±0.5; HS/Ipra: 1.7±0.6; HS/Los: 1.9±0.8, P<0.05, respectively). The combination treatment also significantly ameliorated glomerulosclerosis, and improved cardiomyocyte hypertrophy and perivascular fibrosis (Figure 1C). Angiotensin II type 1 receptor (AT1R) protein expression level in the kidney was remarkably suppressed in the combination treatment group compared to the other high salt diet groups. The protein expression level of Na+/H+ exchanger isoform 3 (NHE3) and Na+-K+-Cl– cotransporter 2 (NKCC2), two of major sodium transports in the renal tubules, were significantly decreased with losartan monotreatment and combination treatment, but not with ipragliflozin monotreatment (Figure 2).

Conclusions

The dual inhibition of SGLT2 and AT1R effectively improved salt-sensitivity via reducing renal expression levels of the sodium transporters, which eventually lead to renocardiac protection. Thus, the combination treatment could be a novel and useful therapeutic strategy for treating salt-sensitive hypertension and renal injury in non-diabetic patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research

Baseline clinical features in a large-scale registration survey of patient with hypertrophic cardiomyopathy throughout Japan: J-HCM registry study

Background

Hypertrophic cardiomyopathy (HCM) is a most prevalent primary myocardial disorder with heterogeneous clinical features. However, there have been few studies on clinical features of HCM as a prospective cohort. In 2015, we established a large-scale registration survey of patients with HCM throughout Japan, named J-HCM registry study.

Purpose

The aim of this study was to clarify the clinical features of Japanese patients with HCM.

Methods

J-HCM registry study is a prospective, multicenter investigation, consisting of 24 hospitals. This time, we present the baseline clinical characteristics in this survey.

Results

Total 1484 patients were registered. The ages at registration and at diagnosis were 65±15 and 56±17 years, respectively, and 806 patients (54%) were men. Majority of the patients (95%) was NYHA class I or II. With regard to subtypes of HCM, there were 526 patients (36%) in the HCM with left ventricular (LV) outflow tract obstruction, 126 patients (8%) in the mid-ventricular obstruction, 57 patients (4%) in the end-stage phase characterized by LV ejection fraction <50%, and 197 patients (14%) in apical HCM. At registration, 80 patients (6%) had prior successful recovery from sustained ventricular tachycardia or ventricular fibrillation, 162 patients (11%) suffered from heart failure hospitalization, and 64 patients (4%) had history of embolic event. Regarding invasive treatment, 160 patients (10%) had prior septal reduction therapy and 162 patients (11%) had ICD implantation. According to the 2014 European Society of Cardiology Guidelines on sudden cardiac death (SCD) prevention, the study patients were divided into 3 categories by the HCM Risk-SCD calculator: patients distribution, 4% in the high risk group (≥6% calculated HCM Risk-SCD at 5 years), 7% in the intermediate risk group (4% to <6%), 69% in the low risk group (<4%), and 16% in the patients with extreme characteristics (Figure 1).

Conclusions

In this multicenter registration survey of patients with HCM, the baseline clinical characteristics were almost similar to several retrospective large-scale cohorts in Western countries except older age and less symptomatic state. This study will provide important knowledge regarding management of HCM.

Figure 1

Funding Acknowledgement

Type of funding source: None

A study on the educational significance of special needs education in basis PHN education - 1st report

Background

For public health nurses to support school-aged children with disabilities who live in the community, it is necessary to understand the mechanism of special needs education and learn the inter-professional collaboration that takes place in it. A survey was conducted on school teachers supporting school-aged children with special needs, and the perception of educational significance in basic PHN education and its related factors were examined.

Methods

In December 2019, a survey questionnaire was sent to all 1,052 special needs schools in Japan. Of the 350 respondents, 330 valid replies were analyzed. Regarding the significance of providing special needs education in basic PHN education, we asked for answers on a four-point scale from “strongly agree” to “strongly disagree” and scored 4 to 1 points. Then, unpaired t-tests were performed between every two groups of “school-targeted type of disabilities,” “respondent's position,” and “respondent's perception/experience.” In addition, Pearson's correlation coefficient test was performed on the relationship with the years of teacher experience in special needs schools.

Results

Perception of the significance of providing education was as follows: “school-targeted type of disabilities” refers to school groups with hearing impairments (p < 0.05), “respondent's position” groups are special needs education coordinators (p < 0.05), “respondent's perception/experience” was significantly higher in the group with a high cognition of PHN work (p < 0.05) and in the group with experience of cooperating with PHN (p < 0.001). However, there was no significant correlation with the years of teacher experience in special needs schools.

Conclusions

There was a high perception of the significance of providing education in school groups with hearing impairment and groups with actual coordination experience, especially where early detection and care were particularly required, regardless of years of teacher experience.

Key messages

Special needs education should be included in basic PHN education to promote inter-professional collaboration for improving QOL of school-age children with disabilities living in communities. To foster the foundation for promoting special needs education in basic PHN education, in-service PHNs need to work closely with schools to meet their expectations for PHNs.

Teriparatide improves microarchitectural characteristics of peri-implant bone in orchiectomized rats

This study evaluated the peri-implant bone repair in orchiectomized rats receiving intermittently PTH 1-34. The treatment returned the bone quality and quantity of the animals to normal in the computerized microtomography, laser confocal microscopy, and histological analysis. The PTH 1-34 promoted marked bone formation with increased volume, improved quality, and greater bone turnover.

INTRODUCTION

Osteoporosis can be a problem in implant osseointegration. So this study aimed to evaluate the quantity and quality of peri-implant bone repair in orchiectomized Wistar rats receiving intermittently administered PTH 1-34.

METHODS

Animals (n = 24) were divided into 3 groups: healthy control (SHAM), orchiectomized (ORQ), and orchiectomized and treated with 0.5 μg/kg/day PTH 1-34 (TERI), and each received an implant in the right and left tibial metaphysis, which was allowed to repair for 60 days. The resultant bone formation was evaluated through computerized microtomography (micro-CT) to compare the percent bone volume (BV/TV), trabecular thickness (Tb.Th), trabecular number and separation (Tb.N, Tb.Sp), and bone implant contact (BIC) through the intersection surface (i.S) between groups. Laser confocal microscopy was used to evaluate fluorochrome areas for mineral apposition rate (MAR) and neoformed bone area (NBA). In addition, histological evaluation of calcified tissues with Stevenel blue and alizarin red staining was performed.

RESULTS

Treatment with PTH 1-34 returned the bone quality and quantity of the osteoporotic animal to normal, as the TERI group presented statistically significant higher values for BV/TV, Tb.Th, and BIC parameters compared with ORQ (p < 0.05), but when compared with SHAM (p > 0.05), no statistical difference was noted. In addition, in the bone turnover analysis (MAR, NBA) for TERI, the highest results are presented, followed by SHAM, and then ORQ (TERI × ORQ: p < 0.05).

CONCLUSIONS

Intermittent treatment with PTH 1-34 on orchiectomized animals promoted marked bone formation with increased volume, improved quality, and greater bone turnover in the peri-implant space, returning the bone quality and quantity to the present standard in healthy animals.

Induction of PD-L1 by Nitric Oxide via JNK Activation in A172 Glioblastoma Cells

Glioblastoma comprises 54% of all the gliomas derived from glial cells and are lethally malignant tumors of the central nervous system (CNS). Glioma cells disrupt the blood-brain barrier, leading to access of circulating immune cells to the CNS. Blocking the interaction between programmed cell death 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) enhances T-cell responses against tumor cells, and inhibition of the PD-1/PD-L1 pathway is used as immunotherapy for cancer, including glioblastoma. Nitric oxide (NO) has multiple physiological roles, such as immune modulation and neural transmission in the CNS. Moreover, it has both tumor-promoting and tumor-suppressive functions. We examined the effects of NOC-18, an NO donor, on the expression of PD-L1 in A172 glioblastoma cells. NOC-18 increased PD-L1 expression in A172 glioblastoma cells. Moreover, this increase is regulated via the c-Jun N-terminal kinase pathway.

P5437The BNP reporter mouse by knock-in technology is useful for the analysis of mechanism in reactivation of BNP in adult heart

Background

It has been thought BNP is induced by undetermined stretch-activated receptors, however, which receptor is associated remains unknown. The stretch-activated receptors include mechanically gated channels, which can be activated by a mechanical stimulus alone, and mechanically modulated channels, which require nonmechanical stimuli such as agonists. It has been recently shown that 1.1kb segment of mouse NPPB promoter dose not reproduce the pattern of reactivation of BNP in adult heart, although it could monitor the expression of BNP in neonatal cardiomyocytes.

Purpose

Our aim is to develop a true BNP reporter mouse and examine whether this mouse is useful or not for the investigation of BNP reactivation mechanism in adult heart and for the measurement of serum-induced BNP expression in patients with heart failure.

Methods

We generated the BNP reporter mice by knocking luciferase cDNA in the initiation site of NPPB. In vivo imaging of luciferase was performed in the BNP reporter mice after the intraperitoneal injection of luciferin. The luciferase activity was examined in neonatal cardiomyocyte, isolated adult cardiomyocytes, adult cardiac dissected tissue with or without 120–150% stretch or angiotensin II stimulation. Left anterior descending (LAD) coronary artery was ligated to study myocardial infarction. Cardiac dissected tissue segments from the BNP reporter mouse were incubated for 8 hours with 20% serum from patients with or without heart failure and the luciferase activity was measured after homogenization.

Results

The in vivo imaging system showed the activity of BNP was high in 1 day-old neonates and the reactivation of BNP in the adult heart after LAD ligation could be monitored by the luciferase activity (figure). The treatment of Ang II could increase the activity of pBNP more than ten folds in heart tissue from adult mice. On the other hand, the 120–150% stretch did not show any effect on the activity of pBNP in this system. We could not observe any activation of pBNP in cultured neonatal or adult cardiomyocytes demonstrated by immunostain with antibodies against luciferase after 120–150% stretch. Interestingly, the luciferase activity was extensively higher in cultured heart tissue segments from the BNP reporter mice after the treatment of serum from patients with heart failure than without heart failure.

In vivo imaging of BNP reporter mice

Conclusion

These results indicate the BNP reporter mouse by knock-in technology is useful for the analysis of mechanism in reactivation of BNP in adult heart and the elevation of BNP in patients of heart failure partly due to the serum-derived induction of BNP from heart.

Glucocorticoids promote breast cancer metastasis

Diversity within or between tumours and metastases (known as intra-patient tumour heterogeneity) that develops during disease progression is a serious hurdle for therapy^1-3. Metastasis is the fatal hallmark of cancer and the mechanisms of colonization, the most complex step in the metastatic cascade⁴, remain poorly defined. A clearer understanding of the cellular and molecular processes that underlie both intra-patient tumour heterogeneity and metastasis is crucial for the success of personalized cancer therapy. Here, using transcriptional profiling of tumours and matched metastases in patient-derived xenograft models in mice, we show cancer-site-specific phenotypes and increased glucocorticoid receptor activity in distant metastases. The glucocorticoid receptor mediates the effects of stress hormones, and of synthetic derivatives of these hormones that are used widely in the clinic as anti-inflammatory and immunosuppressive agents. We show that the increase in stress hormones during breast cancer progression results in the activation of the glucocorticoid receptor at distant metastatic sites, increased colonization and reduced survival. Our transcriptomics, proteomics and phospho-proteomics studies implicate the glucocorticoid receptor in the activation of multiple processes in metastasis and in the increased expression of kinase ROR1, both of which correlate with reduced survival. The ablation of ROR1 reduced metastatic outgrowth and prolonged survival in preclinical models. Our results indicate that the activation of the glucocorticoid receptor increases heterogeneity and metastasis, which suggests that caution is needed when using glucocorticoids to treat patients with breast cancer who have developed cancer-related complications.

Efficacy of the C-terminal telopeptide test in predicting the development of bisphosphonate-related osteonecrosis of the jaw: a systematic review

This systematic review evaluated the efficacy of the morning fasting serum C-terminal telopeptide (CTX) test in predicting the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ). A comprehensive search of studies published up to March 2016, and listed in the PubMed/MEDLINE, Web of Science, and Cochrane Library databases, was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This review has been registered in the PROSPERO international prospective register of systematic reviews (CRD42016036717). The search identified 542 publications; eight studies were finally deemed eligible for inclusion according to the study criteria. These studies included a total 1442 patients (mean age 66.7 years). The most prescribed drug was alendronate, with osteoporosis being the most frequent indication for the prescription of bisphosphonates. Tooth extraction was the most common trigger for BRONJ. Of all patients evaluated after bisphosphonate treatment, only 24 (1.7%) developed BRONJ. All eight of the selected studies found that CTX levels were not predictive of the development of BRONJ. In conclusion, this systematic review indicates that the CTX test has no predictive value in determining the risk of osteonecrosis in patients taking bisphosphonates.

Maxillary sinus lift surgery-with or without graft material? A systematic review

The purpose of this systematic review was to perform a comparative analysis of the use or not of graft material in maxillary sinus lift surgery. Relevant studies published in the last 10 years were identified through a search of the PubMed/MEDLINE, ScienceDirect, and Cochrane Library databases and were assessed against the study inclusion and exclusion criteria. The initial search resulted in 1037 articles. After applying the inclusion and exclusion criteria, 16 articles remained. Four hundred and thirty-six patients were followed up over a postoperative period ranging from 6 months to 11 years. In total, 868 implants were installed in 397 maxillary sinuses. The implant survival rate was 96.00% for surgeries performed without graft material and 99.60% for those in which biomaterial was used, within a follow-up period of 48 to 60 months. In conclusion, maxillary sinus lift surgery, with or without graft material, is a safe procedure with a low complication rate and predictable results.

Raloxifene enhances peri-implant bone healing in osteoporotic rats

The aim of this study was to evaluate bone healing at the bone-implant interface in rats with induced osteoporosis. The rats underwent a bilateral ovariectomy (OVX) and were fed a low calcium and phosphate diet. The OVX rats were divided into three groups: one was treated with raloxifene (OVX-RAL), one with alendronate (OVX-ALE), and one received no medication (OVX-NT). The control group rats (SHAM-DN) underwent sham surgery and were fed a normal diet. Each animal received one implant in each tibia: a machined surface implant in the right tibia and an implant with surface etching in the left tibia. All animals were euthanized after 42 days. Analysis of variance (ANOVA) and Tukey post hoc tests were applied to the biomechanics (reverse torque) and bone-implant contact (BIC) data (P<0.05). The RAL and ALE groups showed improved peri-implant bone healing. However, the ALE group showed no significant difference from the OVX-NT group. Surface treatment promoted higher corticalization at the bone-implant interface, but showed the same characteristics of mature bone and bone neoformation in concentric laminations as the machined implant. There were no statistically significant differences in reverse torque (P=0.861) or BIC (P=0.745) between the OVX-RAL and SHAM-DN groups. Therefore, the use of raloxifene resulted in good biomechanical, BIC, and histological findings in the treatment of induced osteoporosis in rats.

Establishment and characterization of novel human primary and metastatic anaplastic thyroid cancer cell lines and their genomic evolution over a year as a primagraft

CONTEXT

Anaplastic thyroid cancer (ATC) has no effective treatment, resulting in a high rate of mortality. We established cell lines from a primary ATC and its lymph node metastasis, and investigated the molecular factors and genomic changes associated with tumor growth.

OBJECTIVE

The aim of the study was to understand the molecular and genomic changes of highly aggressive ATC and its clonal evolution to develop rational therapies.

DESIGN

We established unique cell lines from primary (OGK-P) and metastatic (OGK-M) ATC specimen, as well as primagraft from the metastatic ATC, which was serially xeno-transplanted for more than 1 year in NOD scid gamma mice were established. These cell lines and primagraft were used as tools to examine gene expression, copy number changes, and somatic mutations using RNA array, SNP Chip, and whole exome sequencing.

RESULTS

Mice carrying sc (OGK-P and OGK-M) tumors developed splenomegaly and neutrophilia with high expression of cytokines including CSF1, CSF2, CSF3, IL-1β, and IL-6. Levels of HIF-1α and its targeted genes were also elevated in these tumors. The treatment of tumor carrying mice with Bevacizumab effectively decreased tumor growth, macrophage infiltration, and peripheral WBCs. SNP chip analysis showed homozygous deletion of exons 3-22 of the PARD3 gene in the cells. Forced expression of PARD3 decreased cell proliferation, motility, and invasiveness, restores cell-cell contacts and enhanced cell adhesion. Next generation exome sequencing identified the somatic changes present in the primary, metastatic, and primagraft tumors demonstrating evolution of the mutational signature over the year of passage in vivo.

CONCLUSION

To our knowledge, we established the first paired human primary and metastatic ATC cell lines offering unique possibilities for comparative functional investigations in vitro and in vivo. Our exome sequencing also identified novel mutations, as well as clonal evolution in both the metastasis and primagraft.

Variegated clonality and rapid emergence of new molecular lesions in xenografts of acute lymphoblastic leukemia are associated with drug resistance

The use of genome-wide copy-number analysis and massive parallel sequencing has revolutionized the understanding of the clonal architecture of pediatric acute lymphoblastic leukemia (ALL) by demonstrating that this disease is composed of highly variable clonal ancestries following the rules of Darwinian selection. The current study aimed to analyze the molecular composition of childhood ALL biopsies and patient-derived xenografts with particular emphasis on mechanisms associated with acquired chemoresistance. Genomic DNA from seven primary pediatric ALL patient samples, 29 serially passaged xenografts, and six in vivo selected chemoresistant xenografts were analyzed with 250K single-nucleotide polymorphism arrays. Copy-number analysis of non-drug-selected xenografts confirmed a highly variable molecular pattern of variegated subclones. Whereas primary patient samples from initial diagnosis displayed a mean of 5.7 copy-number alterations per sample, serially passaged xenografts contained a mean of 8.2 and chemoresistant xenografts a mean of 10.5 copy-number alterations per sample, respectively. Resistance to cytarabine was explained by a new homozygous deletion of the DCK gene, whereas methotrexate resistance was associated with monoallelic deletion of FPGS and mutation of the remaining allele. This study demonstrates that selecting for chemoresistance in xenografted human ALL cells can reveal novel mechanisms associated with drug resistance.

Abstract 5570: Laminin-5 gamma-2 (LAMC2) is highly expressed in anaplastic thyroid carcinoma and is associated with tumor progression, migration and invasion by modulating signaling of EGFR

Context: Anaplastic thyroid carcinoma (ATC) is an aggressive malignancy having no effective treatment. Laminin subunit gamma-2 (LAMC2) is an epithelial basement membrane protein involved in cell migration and tumour invasion and might represent an ideal target for the development of novel therapeutic approaches for ATC.

Objective: Study the role of LAMC2 in ATC tumorigenesis.

Design: LAMC2 expression was evaluated by RT-PCR, western blotting and immunohistochemistry in tumor specimens, adjacent non-cancerous tissues and cell lines. shRNA approach was used to investigate the effect of LAMC2 knockdown on tumorigenesis of ATC.

Results: LAMC2 was highly expressed in ATC samples and cell lines compared to normal thyroid tissues. Silencing LAMC2 by shRNA in ATC cells moderately inhibited cell growth in liquid culture and dramatically decreased growth in soft agar and in xenografts growing in immunodeficient mice. Silencing LAMC2 caused cell cycle arrest and significantly suppressed migration, invasion and wound healing of ATC cells. Rescue experiments by overexpressing LAMC2 in LAMC2 knockdown cells, reversed the inhibitory effects as shown by increased cell proliferation and colony formation. Microarray data demonstrated that LAMC2 shRNA significantly altered expression of genes associated with migration, invasion, proliferation and survival. Immunoprecipitation and co-localization experiments showed that LAMC2 bound to EGFR in ATC cells. Silencing LAMC2 partially blocked EGF-mediated activation of EGFR and its downstream pathway. Interestingly, cetuximab (EGFR blocking antibody) or EGFR siRNA additively enhanced the anti-proliferative activity of the LAMC2 knockdown ATC cells compared to control cells.

Conclusions: To our knowledge, this is the first report investigating the effect of LAMC2 on cell growth, cell cycle, migration, invasion and EGFR signaling in ATC cells, suggesting that LAMC2 may be a potential therapeutic target for treatment of ATC.

Citation Format: Manoj Garg, Deepika Kanojia, Ryoko Okamoto, Vikas Madan, Wenwen Chien, Abhishek Sampath, Ling-Wen Ding, Meng Xuan, Jonathan W Said, Ngan Doan, Li-Zhen Liu, Henry Yang, Sigal Gery, Gleen D Braunstein, H.Phillip Koeffler. Laminin-5 gamma-2 (LAMC2) is highly expressed in anaplastic thyroid carcinoma and is associated with tumor progression, migration and invasion by modulating signaling of EGFR. [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 5570. doi:10.1158/1538-7445.AM2014-5570

Deficiency of CCAAT/enhancer binding protein-epsilon reduces atherosclerotic lesions in LDLR-/- mice

The CCAAT/enhancer binding proteins (C/EBPs) are transcription factors involved in hematopoietic cell development and induction of several inflammatory mediators. C/EBPε is expressed only in myeloid cells including monocytes/macrophages. Atherosclerosis is an inflammatory disorder of the vascular wall and circulating immune cells such as monocytes/macrophages. Mice deficient in the low density lipoprotein (LDL) receptor (Ldlr−/−) fed on a high cholesterol diet (HCD) show elevated blood cholesterol levels and are widely used as models to study human atherosclerosis. In this study, we generated Ldlr and Cebpe double-knockout (llee) mice and compared their atherogenic phenotypes to Ldlr single deficient (llEE) mice after HCD. Macrophages from llee mice have reduced lipid uptake by foam cells and impaired phagokinetic motility in vitro compared to macrophages from llEE mice. Also, compared to llEE mice, llee mice have alterations of lipid metabolism, and reduced atheroma and obesity, particularly the males. Peritoneal macrophages of llee male mice have reduced mRNA expression of FABP4, a fatty acid binding protein implicated in atherosclerosis. Overall, our study suggests that the myeloid specific factor C/EBPε is involved in systemic lipid metabolism and that silencing of C/EBPε could decrease the development of atherosclerosis.

Laminin-5γ-2 (LAMC2) is highly expressed in anaplastic thyroid carcinoma and is associated with tumor progression, migration, and invasion by modulating signaling of EGFR

CONTEXT

Anaplastic thyroid carcinoma (ATC) is an aggressive malignancy having no effective treatment. Laminin subunit-γ-2 (LAMC2) is an epithelial basement membrane protein involved in cell migration and tumor invasion and might represent an ideal target for the development of novel therapeutic approaches for ATC.

OBJECTIVE

The objective of the investigation was to study the role of LAMC2 in ATC tumorigenesis.

DESIGN

LAMC2 expression was evaluated by RT-PCR, Western blotting, and immunohistochemistry in tumor specimens, adjacent noncancerous tissues, and cell lines. The short hairpin RNA (shRNA) approach was used to investigate the effect of LAMC2 knockdown on the tumorigenesis of ATC.

RESULTS

LAMC2 was highly expressed in ATC samples and cell lines compared with normal thyroid tissues. Silencing LAMC2 by shRNA in ATC cells moderately inhibited cell growth in liquid culture and dramatically decreased growth in soft agar and in xenografts growing in immunodeficient mice. Silencing LAMC2 caused cell cycle arrest and significantly suppressed the migration, invasion, and wound healing of ATC cells. Rescue experiments by overexpressing LAMC2 in LAMC2 knockdown cells reversed the inhibitory effects as shown by increased cell proliferation and colony formation. Microarray data demonstrated that LAMC2 shRNA significantly altered the expression of genes associated with migration, invasion, proliferation, and survival. Immunoprecipitation studies showed that LAMC2 bound to epidermal growth factor receptor (EGFR) in the ATC cells. Silencing LAMC2 partially blocked epidermal growth factor-mediated activation of EGFR and its downstream pathway. Interestingly, cetuximab (an EGFR blocking antibody) or EGFR small interfering RNA additively enhanced the antiproliferative activity of the LAMC2 knockdown ATC cells compared with the control cells.

CONCLUSIONS

To our knowledge, this is the first report investigating the effect of LAMC2 on cell growth, cell cycle, migration, invasion, and EGFR signaling in ATC cells, suggesting that LAMC2 may be a potential therapeutic target for the treatment of ATC.

Off-target effects of c-MET inhibitors on thyroid cancer cells

Aberrantly activated c-MET signaling occurs in several cancers, promoting the development of c-MET inhibitors. In this study, we found that eight of eight thyroid cancer cell lines (including six anaplastic thyroid cell lines) have prominent expression of c-MET protein. Fifty percent of the thyroid cancer cell lines (four of eight) were growth inhibited by two small molecule c-MET inhibitors (tivantinib and crizotinib) associated with apoptosis and G(2)-M cell-cycle arrest. However, crizotinib did not inhibit 50% proliferation of thyroid cancer cells (SW1736 and TL3) at a concentration at which the drug completely inhibited ligand-stimulated c-MET phosphorylation. However, tivantinib was less potent than crizotinib at inhibiting c-MET phosphorylation, but was more potent than crizotinib at decreasing cell growth. Suppressing c-MET protein expression and phosphorylation using siRNA targeting c-MET did not induce cell-cycle arrest and apoptosis. Taken together, tivantinib and crizotinib have off-target(s) activity, contributing to their antitumor activity. In vivo study showed that crizotinib markedly inhibited the growth of thyroid cancer cells (SW1736) in immunodeficient mice. In summary, c-MET inhibitors (tivantinib and crizotinib) suppress the growth of aggressive thyroid cancer cells, and this potential therapeutic benefit results from their non-MET-targeting effects.

Novel Gemini vitamin D3 analogs: large structure/function analysis and ability to induce antimicrobial peptide

We have synthesized 39 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] analogs having two side chains attached to carbon-20 (Gemini) with various modifications and compared their anticancer activities. Five structure-function rules emerged to identify analogs with enhanced anticancer activity. One of these active analogs, BXL-01-0126, was more potent than 1,25(OH)2D3 in mediating 50% clonal inhibition of cancer cell growth. Murine studies found that BXL-01-0126 and 1,25(OH)2D3 had nearly the same potency to raise serum calcium levels. Taken together, BXL-01-0126 when compared to 1,25(OH)2D3 has greater anticancer potency, but similar toxicity causing hypercalcemia. We focused on the effect of these compounds on the stimulation of expression of human cathelicidin antimicrobial peptide (CAMP) whose gene has a vitamin D response element in its promoter. Expression of CAMP mRNA and protein increased in a dose-response fashion after exposure of acute myeloid leukemia (AML) cells to the Gemini analog, BXL-01-126, in vitro. A xenograft model of AML was developed using U937 AML cells injected into NSG-immunodeficient mice. Administration of vitamin D3 compounds to these mice resulted in substantial levels of CAMP in the systemic circulation. This suggests a unique prophylactic treatment at diagnosis or during induction chemotherapy for AML patients to provide them with protection against various microbial infections through CAMP induction.

Effect of dasatinib against thyroid cancer cell lines in vitro and a xenograft model in vivo

Tyrosine kinase inhibitors (TKIs) have emerged as a promising class of agents against thyroid cancer. The aim of the present study was to investigate the in vitro and in vivo activity of dasatinib against a panel of thyroid cancer cell lines and explore possible mechanisms of action, using various assays and western blotting. Our results showed that dasatinib exhibits prominent cytostatic activity both in vitro and in vivo against thyroid cancer cell lines with RET/PTC rearrangement (BHP2-7) and KRAS mutation (Cal62). Although dasatinib has primarily been described as an ABL/SRCfamily kinase inhibitor, the cytostatic activity observed in the present study is mediated by several off-target effects of dasatinib, some of which have not previously been reported. These effects include a reduction in phospho-FAK, FAK, RAS, Caveolin and SYK protein levels and an increase in β-catenin protein expression, which leads to the induction of senescence, an increase in the adhesiveness of the cells, a decrease in reactive oxygen species level, and changes in the expression profile of molecules involved in cellular adhesion such as integrins. Therefore, we propose that dasatinib is an effective therapeutic agent for certain patients with thyroid cancer, and these candidate patients may be identifiable on the basis of standard genotypic analyses.

Inecalcitol, an analog of 1α,25(OH)(2) D(3) , induces growth arrest of androgen-dependent prostate cancer cells

19-nor-14-epi-23-yne-1,25(OH)(2) D(3) (inecalcitol) is a unique vitamin D(3) analog. We evaluated the activity of inecalcitol in a human prostate cancer model system. The analog was 11-fold more potent than 1,25(OH)(2) D(3) in causing 50% clonal growth inhibition of androgen-sensitive human prostate cancer LNCaP cells. Inecalcitol, more than 1,25(OH)(2) D(3) , reduced in a dose-dependent manner the expression levels of the transcription factor ETS variant 1 and the serine/threonine protein kinase Pim-1, both of which are upregulated in prostate cancer. Remarkably, dose challenge experiments revealed that inecalcitol maximal tolerated dose (MTD) by intraperitoneal (i.p.) administration was 30 μg/mouse (1,300 μg/kg) three times per week, while we previously found that the MTD of 1,25(OH)(2) D(3) is 0.0625 μg/mouse; therefore, inecalcitol is 480 times less hypercalcemic than 1,25(OH)(2) D(3) . Pharmacokinetic studies showed that plasma half-life of inecalcitol were 18.3 min in mice. A xenograft model of LNCaP cells was developed in immunodeficient mice treated with inecalcitol. The tumors of the diluent-treated control mice increased in size but those in the inecalcitol treatment group did not grow. Our data suggest that inecalcitol inhibits androgen-responsive prostate cancer growth in vivo and should be examined either alone or with other chemotherapy in clinical trials in individuals with rising serum prostate-specific antigen after receiving either surgery or irradiation therapy with curative intent.

Multiple ulcers in the small and large intestines occurred during tocilizumab therapy for rheumatoid arthritis

Tocilizumab is a monoclonal antibody against human interleukin-6 receptor which blocks the binding of interleukin-6 to its receptor. Tocilizumab is effective for the treatment of inflammatory disorders including rheumatoid arthritis. We report a case of multiple ulcers in the small and large intestines, which occurred during tocilizumab therapy. A 57-year-old woman started to use tocilizumab for rheumatoid arthritis. Three months later, she complained of hematochezia. Double-balloon endoscopy revealed multiple small aphthoid ulcers in the small and large intestines. One month after the woman had recovered, she was given tocilizumab again. The woman had hematochezia and abdominal pain again 2 weeks later. Colonoscopy revealed multiple round, discrete punched-out ulcers in the terminal ileum, and vast deep ulcers from the cecum to the descending colon. Bioptic histopathology and cultivation showed non-specific findings. Six weeks after discontinuation of tocilizumab, ulcers in the small and large intestine dramatically improved, leaving ulcer scars. This disease course and the results of examination made us strongly suspect that tocilizumab induced multiple ulcers in the small and large intestines. Interleukin-6 is a pleiotropic cytokine and involved in intestinal mucosal wound healing as well as in inflammatory processes. It is possible that tocilizumab inhibited tissue repair of the intestine and caused intestinal ulcers.

In vivo deficiency of both C/EBPβ and C/EBPε results in highly defective myeloid differentiation and lack of cytokine response

The CCAAT/enhancer binding proteins (C/EBPs) are transcription factors involved in hematopoietic cell development and induction of several inflammatory mediators. Here, we generated C/EBPβ and C/EBPε double-knockout (bbee) mice and compared their phenotypes to those of single deficient (bbEE and BBee) and wild-type (BBEE) mice. The bbee mice were highly susceptible to fatal infections and died within 2-3 months. Morphologically, their neutrophils were blocked at the myelocytes/metamyelocytes stage, and clonogenic assays of bone marrow cells indicated a significant decrease in the number of myeloid colonies of the bbee mice. In addition, the proportion of hematopoietic progenitor cells [Lin(-)Sca1(+)c-Kit(+)] in the bone marrow of the bbee mice was significantly increased, reflecting the defective differentiation of the myeloid compartment. Furthermore, microarray expression analysis of LPS- and IFNγ-activated bone marrow-derived macrophages from bbee compared to single knockout mice revealed decreased expression of essential immune response-related genes and networks, including some direct C/EBP-targets such as Marco and Clec4e. Overall, the phenotype of the bbee mice is distinct from either the bbEE or BBee mice, demonstrating that both transcription factors are crucial for the maturation of neutrophils and macrophages, as well as the innate immune system, and can at least in part compensate for each other in the single knockout mice.

Clinical and endoscopic characteristics of acute haemorrhagic rectal ulcer, and endoscopic haemostatic treatment: a retrospective study of 95 patients

AIM

Acute haemorrhagic rectal ulcer (AHRU) is characterized by sudden onset of painless and massive rectal bleeding in elderly bedridden patients who have serious illness. Endoscopic diagnosis and management of AHRU is, however, still controversial. We retrospectively investigated 95 AHRU patients to elucidate the clinical characteristics, endoscopic findings and haemostatic strategies.

METHOD

Between January 1999 and March 2007, 95 patients were diagnosed with AHRU in our hospital. Medical records and colonoscopy files were reviewed. Clinical features, colonoscopic findings, haemostatic treatment and outcome of the patients were evaluated.

RESULTS

Eighty per cent of the patients were bedridden at the onset. The most frequent underlying disorder was cerebrovascular disease (36.8%). Hypoalbuminaemia (< 3.5 g/dl) was seen in 92.6% of the patients. Endoscopic findings of AHRU were classified as circumferential ulcer (41.1%), linear or nearly round small ulcer(s) (44.2%), circumferential and small ulcer(s) (7.4%) and Dieulafoy-like ulcer (7.4%). Primary endoscopic haemostatic treatment was performed in 45.3% of cases. Recurrent bleeding occurred in 24.2% of patients. Permanent haemostasis was achieved by secondary endoscopic treatment in 82.6% of re-bleeding patients.

CONCLUSION

Understanding the typical clinical and endoscopic findings and careful endoscopic examination are important for the accurate diagnosis of AHRU, and endoscopic haemostatic therapy may be effective for bleeding patients.