Experimental capabilities for liquid jet samples at sub-MHz rates at the FXE Instrument at European XFEL

The Femtosecond X-ray Experiments (FXE) instrument at the European X-ray Free-Electron Laser (EuXFEL) provides an optimized platform for investigations of ultrafast physical, chemical and biological processes. It operates in the energy range 4.7-20 keV accommodating flexible and versatile environments for a wide range of samples using diverse ultrafast X-ray spectroscopic, scattering and diffraction techniques. FXE is particularly suitable for experiments taking advantage of the sub-MHz repetition rates provided by the EuXFEL. In this paper a dedicated setup for studies on ultrafast biological and chemical dynamics in solution phase at sub-MHz rates at FXE is presented. Particular emphasis on the different liquid jet sample delivery options and their performance is given. Our portfolio of high-speed jets compatible with sub-MHz experiments includes cylindrical jets, gas dynamic virtual nozzles and flat jets. The capability to perform multi-color X-ray emission spectroscopy (XES) experiments is illustrated by a set of measurements using the dispersive X-ray spectrometer in von Hamos geometry. Static XES data collected using a multi-crystal scanning Johann-type spectrometer are also presented. A few examples of experimental results on ultrafast time-resolved X-ray emission spectroscopy and wide-angle X-ray scattering at sub-MHz pulse repetition rates are given.

The Induction of Parathyroid Cell Differentiation from Human Induced Pluripotent Stem Cells Promoted Via TGF-α/EGFR Signaling

The parathyroid gland plays an essential role in mineral and bone metabolism. Cultivation of physiological human parathyroid cells has yet to be established and the method by which parathyroid cells differentiate from pluripotent stem cells remains uncertain. Therefore, it has been hard to clarify the mechanisms underlying the onset of parathyroid disorders, such as hyperparathyroidism. In this study, we developed a new method of parathyroid cell differentiation from human induced pluripotent stem (iPS) cells. Parathyroid cell differentiation occurred in accordance with embryologic development. Differentiated cells, which expressed the parathyroid hormone, adopted unique cell aggregation similar to the parathyroid gland. In addition, these differentiated cells were identified as calcium-sensing receptor (CaSR)/epithelial cell adhesion molecule (EpCAM) double-positive cells. Interestingly, stimulation with transforming growth factor-α (TGF-α), which is considered a causative molecule of parathyroid hyperplasia, increased the CaSR/EpCAM double-positive cells, but this effect was suppressed by erlotinib, which is an epidermal growth factor receptor (EGFR) inhibitor. These results suggest that TGF-α/EGFR signaling promotes parathyroid cell differentiation from iPS cells in a similar manner to parathyroid hyperplasia.

The level of macrophage migration inhibitory factor is negatively correlated with the efficacy of PD-1 blockade immunotherapy combined with chemotherapy as a neoadjuvant therapy for esophageal squamous cell carcinoma

PURPOSE

This study aimed to screen biomarkers to predict the efficacy of programmed cell death 1 (PD-1) blockade immunotherapy combined with chemotherapy as neoadjuvant therapy for esophageal squamous cell carcinoma (ESCC).

METHODS

In the first stage of the study, the baseline concentrations of 40 tumor-related chemokines in the serum samples of 50 patients were measured to screen for possible biomarkers. We investigated whether the baseline concentration of the selected chemokine was related to the therapeutic outcomes and tumor microenvironment states of patients treated with the therapy. In the second stage, the reliability of the selected biomarkers was retested in 34 patients.

RESULTS

The baseline concentration of macrophage migration inhibitory factor (MIF) was negatively correlated with disease-free survival (DFS) and overall survival (OS) in patients treated with the therapy. In addition, a low baseline expression level of MIF is related to a better tumor microenvironment for the treatment of ESCC. A secondary finding was that effective treatment decreased the serum concentration of MIF.

CONCLUSION

Baseline MIF levels were negatively correlated with neoadjuvant therapy efficacy. Thus, MIF may serve as a predictive biomarker for this therapy. The accuracy of the prediction could be improved if the serum concentration of MIF is measured again after the patient received several weeks of treatment.

Future prospects for cancer immunotherapy using induced pluripotent stem cell-derived dendritic cells or macrophages

Cancer immunotherapy is now the first-line treatment for many unresectable cancers. However, it remains far from a complete cure for all patients. Therefore, it is necessary to develop innovative methods for cancer immunotherapy, and immune cell therapy could be an option. Currently, several institutions are attempting to generate immune cells from induced pluripotent stem cells (iPSCs) for use in cancer immunotherapy. A method for generating dendritic cells (DCs) and macrophages (MPs) from iPSC has been established. iPSC-derived DCs (iPS-DCs) can activate T cells via antigen presentation, and iPSC-derived macrophages (iPS-MPs) attack cancer. Since iPSCs are used as the source, genetic modification is easy, and various immune functions, such as the production of anti-tumour cytokines, can be added. Furthermore, when iPS-DCs and iPS-MPs are immortalized, cost reduction through mass production is theoretically possible. In this review, the achievements of cancer research using iPS-DCs and iPS-MPs are summarized, and the prospects for the future are discussed.

Optimization of the proliferation and persistency of CAR T cells derived from human induced pluripotent stem cells

The effectiveness of chimaeric antigen receptor (CAR) T-cell immunotherapies against solid tumours relies on the accumulation, proliferation and persistency of T cells at the tumour site. Here we show that the proliferation of CD8αβ cytotoxic CAR T cells in solid tumours can be enhanced by deriving and expanding them from a single human induced-pluripotent-stem-cell clone bearing a CAR selected for efficient differentiation. We also show that the proliferation and persistency of the effector cells in the tumours can be further enhanced by genetically knocking out diacylglycerol kinase, which inhibits antigen-receptor signalling, and by transducing the cells with genes encoding for membrane-bound interleukin-15 (IL-15) and its receptor subunit IL-15Rα. In multiple tumour-bearing animal models, the engineered hiPSC-derived CAR T cells led to therapeutic outcomes similar to those of primary CD8 T cells bearing the same CAR. The optimization of effector CAR T cells derived from pluripotent stem cells may aid the development of long-lasting antigen-specific T-cell immunotherapies for the treatment of solid tumours.

Analysis of human glioma-associated co-inhibitory immune checkpoints in glioma microenvironment and peripheral blood

One biomarker for a better therapeutic effect of immune checkpoint inhibitors is high expression of checkpoint in tumor microenvironment The purpose of this study is to investigate the expression of immune checkpoints in human glioma microenvironment and peripheral blood mononuclear cells. First, single-cell suspension from 20 fresh high-grade glioma (HGG) specimens were obtained, and analyzed for lymphocyte composition, then six co-inhibitory immune checkpoints were analyzed at the same time. Second, 36 PBMC specimens isolated from HGG blood samples were analyzed for the same items. In GME, there were four distinct subtypes of cells, among them, immune cells accounted for an average of 51.3%. The myeloid cell population (CD11b⁺) was the most common immune cell identified, accounting for 36.14% on average; the remaining were most CD3⁺CD4⁺ and CD3⁺/CD8⁻/CD4⁻ T lymphocytes. In these cells, we detected the expression of BTLA, LAG3, Tim-3, CTLA-4, and VISTA on varying degrees. While in PBMCs, the result showed that when compared with healthy volunteers, the proportion of NK cells decreased significantly in HGG samples (p < 0.01). Moreover, the expression of BTLA, LAG3, and Tim-3 in CD45⁺ immune cells in PBMC was more remarkable in glioma samples. In conclusion, the CD11b⁺ myeloid cells were the predominant immune cells in GME. Moreover, some immune checkpoints displayed a more remarkable expression on the immune cells in GME. And the profile of checkpoint expression in PBMC was partially consistent with that in GME.

CD11b+DIP2A+LAG3+ cells facilitate immune dysfunction in colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide, and tumor metastasis is the leading cause of death. Targeting immune inhibitory checkpoint inhibitory pathways has attracted great attention, since the therapeutic efficacy induced by the specific blocking antibodies has been demonstrated even in metastatic CRC patients. However, the clinical outcome is low in many cases, and thus more effective treatments are needed in the clinical settings. A SPARC family member follistatin-like 1 (FSTL1) is known as a key driver of tumor metastasis in various types of cancer. However, the immunological roles of the FSTL1 in the CRC pathogenesis remain to be elucidated. In this study, we investigated the molecular mechanisms underlying the refractory FSTL1⁺ CRC using murine and human FSTL1-transduced CRC cells. Also, based on the results, we evaluated anti-tumor efficacy induced by agents targeting the identified molecules using murine CRC metastasis models, and validated the clinical relevancy of the basic findings using tumor tissues and peripheral blood obtained from CRC patients. FSTL1 transduction conferred EMT-like properties, such as low proliferative (dormant) and high invasive abilities, on tumor cells. When the transfectants were subcutaneously implanted in mice, CD11b⁺DIP2A⁺LAG3⁺ cells were abundantly expanded locally and systemically in the mice. Simultaneously, apoptotic T cells increased and were lastly excluded from the tumor tissues, allowing tumor aggravation leading to resistance to anti-PD1/PDL1 treatment. Blocking FSTL1 and LAG3, however, significantly suppressed the apoptosis induction, and successfully induced anti-tumor immune responses in the CRC metastasis models. Both treatments synergized in providing better prognosis of the mice. FSTL1 was significantly upregulated in tumor tissues and peripheral blood of CRC patients, and the CD11b⁺DIP2A⁺LAG3⁺ cells were significantly expanded in the PBMCs as compared to those of healthy donors. The expansion level was significantly correlated with decrease of potent Ki67⁺GZMB⁺ CTLs. These results suggest that the FSTL1-induced CD11b⁺DIP2A⁺LAG3⁺ cells are a key driver of immune dysfunction in CRC. Targeting the FSTL1-LAG3 axis may be a promising strategy for treating metastatic CRC, and anti-FSTL1/LAG3 combination regimen may be practically useful in the clinical settings.

Association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan: a cohort study

Background

There is an ongoing controversy regarding the necessity of single-photon emission computed tomography (SPECT) for patients with ischemic heart diseases after the publication of the results of the ISCHEMIA trial.

Purpose

We aimed to evaluate the association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan.

Methods

From the data of 2780 patients with stable angina who were enrolled prospectively between January 2006 and March 2008 in Japan and had undergone physician-referred non-invasive imaging tests, 1205 patients managed with SPECT were stratified by 10% myocardial ischemia. Major adverse cardiac events (MACEs), including death, myocardial infarction, hospitalization for heart failure, and late revascularization, were followed-up for 1 year.

Results

Patients with ≥10% myocardial ischemia (n=173) were older than patients with &lt;10% myocardial ischemia (n=1032) and had a significantly higher 1-year cumulative incidence of MACEs (9.1% vs. 1.2%, P&lt;0.0001). After adjusting for confounders, the risk of ≥10% myocardial ischemia relative to &lt;10% myocardial ischemia for MACEs remained significant (adjusted hazard ratio [95% confidence interval], 2.40 [1.09–5.26], P=0.029).

Conclusion

The presence of ≥10% myocardial ischemia was significantly associated with the 1-year risk for MACEs in Japanese patients with suspected coronary artery disease.

Funding Acknowledgement

Type of funding sources: None. Study flowchartOutcomes

Improved safety of induced pluripotent stem cell-derived antigen-presenting cell-based cancer immunotherapy

The tumorigenicity and toxicity of induced pluripotent stem cells (iPSCs) and their derivatives are major safety concerns in their clinical application. Recently, we developed granulocyte-macrophage colony-stimulating factor (GM-CSF)-producing proliferating myeloid cells (GM-pMCs) from mouse iPSCs as a source of unlimited antigen-presenting cells for use in cancer immunotherapy. As GM-pMCs are generated by introducing c-Myc and Csf2 into iPSC-derived MCs and are dependent on self-produced GM-CSF for proliferation, methods to control their proliferation after administration should be introduced to improve safety. In this study, we compared the efficacy of two promising suicide gene systems, herpes simplex virus-thymidine kinase (HSV-TK)/ganciclovir (GCV) and inducible caspase-9 (iCasp9)/AP1903, for safeguarding GM-pMCs in cancer immunotherapy. The expression of HSV-TK or iCasp9 did not impair the fundamental properties of GM-pMCs. Both of these suicide gene-expressing cells selectively underwent apoptosis after treatment with the corresponding apoptosis-inducing drug, and they were promptly eliminated in vivo. iCasp9/AP1903 induced apoptosis more efficiently than HSV-TK/GCV. Furthermore, high concentrations of GCV were toxic to cells not expressing HSV-TK, whereas AP1903 was bioinert. These results suggest that iCasp9/AP1903 is superior to HSV-TK/GCV in terms of both safety and efficacy when controlling the fate of GM-pMCs after priming antitumor immunity.

Type I Interferon Delivery by iPSC-Derived Myeloid Cells Elicits Antitumor Immunity via XCR1+ Dendritic Cells

Type I interferons (IFNs) play important roles in antitumor immunity. We generated IFN-α-producing cells by genetically engineered induced pluripotent stem cell (iPSC)-derived proliferating myeloid cells (iPSC-pMCs). Local administration of IFN-α-producing iPSC-pMCs (IFN-α-iPSC-pMCs) alters the tumor microenvironment and propagates the molecular signature associated with type I IFN. The gene-modified cell actively influences host XCR1⁺ dendritic cells to enhance CD8⁺ T cell priming, resulting in CXCR3-dependent and STING-IRF3 pathway-independent systemic tumor control. Administration of IFN-α-iPSC-pMCs in combination with immune checkpoint blockade overcomes resistance to single-treatment modalities and generates long-lasting antitumor immunity. These preclinical data suggest that IFN-α-iPSC-pMCs might constitute effective immune-stimulating agents for cancer that are refractory to checkpoint blockade.

Visualization of ferroaxial domains in an order-disorder type ferroaxial crystal

Ferroaxial materials that exhibit spontaneous ordering of a rotational structural distortion with an axial vector symmetry have gained growing interest, motivated by recent extensive studies on ferroic materials. As in conventional ferroics (e.g., ferroelectrics and ferromagnetics), domain states will be present in the ferroaxial materials. However, the observation of ferroaxial domains is non-trivial due to the nature of the order parameter, which is invariant under both time-reversal and space-inversion operations. Here we propose that NiTiO₃ is an order-disorder type ferroaxial material, and spatially resolve its ferroaxial domains by using linear electrogyration effect: optical rotation in proportion to an applied electric field. To detect small signals of electrogyration (order of 10⁻⁵ deg V⁻¹), we adopt a recently developed difference image-sensing technique. Furthermore, the ferroaxial domains are confirmed on nano-scale spatial resolution with a combined use of scanning transmission electron microscopy and convergent-beam electron diffraction. Our success of the domain visualization will promote the study of ferroaxial materials as a new ferroic state of matter.

The presence of ferroaxial domain states is recently experimentally demonstrated by a nonlinear optical technique, which lacks high spatial resolution to visualize ferroaxial domains. Here, the authors visualize spatial distributions of ferroaxial domains in NiTiO₃ showing an order-disorder type ferroaxial transition.

Generation of GM-CSF-producing antigen-presenting cells that induce a cytotoxic T cell-mediated antitumor response

Immunotherapy using dendritic cells (DCs) is a promising treatment modality for cancer. However, the limited number of functional DCs from peripheral blood has been linked to the unsatisfactory clinical efficacies of current DC-based cancer immunotherapies. We previously generated proliferating antigen-presenting cells (APCs) by genetically engineering myeloid cells derived from induced pluripotent stem cells (iPSC-pMCs), which offer infinite functional APCs for broad applications in cancer therapy. Herein, we aimed to further enhance the antitumor effect of these cells by genetic modification. GM-CSF gene transfer did not affect the morphology, or surface phenotype of the original iPSC-pMCs, however, it did impart good viability to iPSC-pMCs. The resultant cells induced GM-CSF-dependent CD8⁺ T cell homeostatic proliferation, thereby enhancing antigen-specific T cell priming in vitro. Administration of the tumor antigen-loaded GM-CSF-producing iPSC-pMCs (GM-pMCs) efficiently stimulated antigen-specific T cells and promoted effector cell infiltration of the tumor tissues, leading to an augmented antitumor effect. To address the potential tumorigenicity of iPSC-derived products, irradiation was applied and found to restrict the proliferation of GM-pMCs, while retaining their T cell-stimulatory capacity. Furthermore, the irradiated cells exerted an antitumor effect equivalent to that of bone marrow-derived DCs obtained from immunocompetent mice. Additionally, combination with immune checkpoint inhibitors increased the infiltration of CD8⁺ or NK1.1⁺ effector cells and decreased CD11b⁺/Gr-1⁺ cells without causing adverse effects. Hence, although GM-pMCs have certain characteristics that differ from endogenous DCs, our findings suggest the applicability of these cells for broad clinical use and will provide an unlimited source of APCs with uniform quality.

Induced pluripotent stem cell-derived myeloid cells expressing OX40 ligand amplify antigen-specific T cells in advanced melanoma

Immune checkpoint inhibitors improved the survival rate of patients with unresectable melanoma. However, some patients do not respond, and variable immune-related adverse events have been reported. Therefore, more effective and antigen-specific immune therapies are urgently needed. We previously reported the efficacy of an immune cell therapy with immortalized myeloid cells derived from induced pluripotent stem cells (iPS-ML). In this study, we generated OX40L-overexpressing iPS-ML (iPS-ML-Zsgreen-OX40L) and investigated their characteristics and in vivo efficacy against mouse melanoma. We found that iPS-ML-Zsgreen-OX40L suppressed the progression of B16-BL6 melanoma, and prolonged survival of mice with ovalbumin (OVA)-expressing B16 melanoma (MO4). The number of antigen-specific CD8⁺ T cells was higher in spleen cells treated with OVA peptide-pulsed iPS-ML-Zsgreen-OX40L than in those without OX40L. The OVA peptide-pulsed iPS-ML-Zsgreen-OX40L significantly increased the number of tumor-infiltrating T lymphocytes (TILs) in MO4 tumor. Flow cytometry showed decreased regulatory T cells but increased effector and effector memory T cells among the TILs. Although we plan to use allogeneic iPS-ML in the clinical applications, iPS-ML showed the tumorgenicity in the syngeneic mice model. Incorporating the suicide gene is necessary to ensure the safety in the future study. Collectively, these results indicate that iPS-ML-Zsgreen-OX40L therapy might be a new method for antigen-specific cancer immunotherapy.

Non-clinical efficacy, safety and stable clinical cell processing of induced pluripotent stem cell-derived anti-glypican-3 chimeric antigen receptor-expressing natural killer/innate lymphoid cells

The use of allogeneic, pluripotent stem‐cell‐derived immune cells for cancer immunotherapy has been the subject of recent clinical trials. In Japan, investigator‐initiated clinical trials will soon begin for ovarian cancer treatment using human leukocyte antigen (HLA)‐homozygous‐induced pluripotent stem cell (iPSC)‐derived anti–glypican‐3 (GPC3) chimeric antigen receptor (CAR)‐expressing natural killer/innate lymphoid cells (NK/ILC). Using pluripotent stem cells as the source for allogeneic immune cells facilitates stringent quality control of the final product, in terms of efficacy, safety and producibility. In this paper, we describe our methods for the stable, feeder‐free production of CAR‐expressing NK/ILC cells from CAR‐transduced iPSC with clinically relevant scale and materials. The average number of cells that could be differentiated from 1.8‐3.6 × 10⁶ iPSC within 7 weeks was 1.8‐4.0 × 10⁹. These cells showed stable CD45/CD7/CAR expression, effector functions of cytotoxicity and interferon gamma (IFN‐γ) production against GPC3‐expressing tumor cells. When the CAR‐NK/ILC cells were injected into a GPC3‐positive, ovarian‐tumor‐bearing, immunodeficient mouse model, we observed a significant therapeutic effect that prolonged the survival of the animals. When the cells were injected into immunodeficient mice during non–clinical safety tests, no acute systemic toxicity or tumorigenicity of the final product or residual iPSC was observed. In addition, our test results for the CAR‐NK/ILC cells generated with clinical manufacturing standards are encouraging, and these methods should accelerate the development of allogeneic pluripotent stem cell‐based immune cell cancer therapies.

Current state and future of co-inhibitory immune checkpoints for the treatment of glioblastoma

In the interaction between a tumor and the immune system, immune checkpoints play an important role, and in tumor immune escape, co-inhibitory immune checkpoints are important. Immune checkpoint inhibitors (ICIs) can enhance the immune system’s killing effect on tumors. To date, impressive progress has been made in a variety of tumor treatments; PD1/PDL1 and CTLA4 inhibitors have been approved for clinical use in some tumors. However, glioblastoma (GBM) still lacks an effective treatment. Recently, a phase III clinical trial using nivolumab to treat recurrent GBM showed no significant improvement in overall survival compared to bevacizumab. Therefore, the use of immune checkpoints in the treatment of GBM still faces many challenges. First, to clarify the mechanism of action, how different immune checkpoints play roles in tumor escape needs to be determined; which biomarkers predict a benefit from ICIs treatment and the therapeutic implications for GBM based on experiences in other tumors also need to be determined. Second, to optimize combination therapies, how different types of immune checkpoints are selected for combined application and whether combinations with targeted agents or other immunotherapies exhibit increased efficacy need to be addressed. All of these concerns require extensive basic research and clinical trials. In this study, we reviewed existing knowledge with respect to the issues mentioned above and the progress made in treatments, summarized the state of ICIs in preclinical studies and clinical trials involving GBM, and speculated on the therapeutic prospects of ICIs in the treatment of GBM.

Abstract 1432: Enhanced effector responses of regenerated CAR-T cells derived from genome edited iPSCs

Chimeric antigen receptor (CAR) is an artificial protein that provides HLA-independent antigen specificity to T cells. CAR-T therapy has shown remarkable clinical responses especially in hematologic malignancies. But this therapy requires cell preparation for each patient and it cause some limitations for applicability of CAR-T therapy. We have reported regeneration of T cells from iPSCs (Cell Stem Cell. 2013). Since this technology can provide unlimited number of T cells, CAR-T therapy using iPSCs is thought to broaden its applicability. To target solid tumors, it is important to avoid immunosuppressive factors from tumor microenvironment and to exert sufficient cytotoxicity. Tumor reactive T cells are known to fall into anergy state by continuous antigen stimulations. To overcome immunosuppression in tumor microenvironment, enhancement of TCR signaling by modification of genes related to TCR signal is a promising strategy. Recent studies revealed that the efficacy of CAR-iPS-T cells are not equivalent to primary CAR-T cells. To enhance the efficacy of CAR-iPS-T cells and to produce resistant CAR-T cells to immunosuppression, we focused on TCR signaling pathway. We found that antigen reactivity of CAR-iPS-T cells was insufficient compared with primary CAR-T cells. To overcome the weakness of TCR signal, we disrupted genes negatively related to TCR signal and successfully enhanced TCR signal. As a result, genome edited CAR-iPS-T cells could persist longer in vivo and displayed enhanced tumor suppressive function comparable with primary CAR-T cells. Genome edited iPSCs can be a unlimited cell source of enhanced CAR-T cells. These findings indicate that regenerated CAR-T cells derived from genome edited iPSCs would be a promising CAR-T therapy which would overcome immunosuppressive tumor microenvironment.

Citation Format: Tatsuki Ueda, Shoichi Iriguchi, Yohei Kawai, Atsutaka Minagawa, Hiroyuki Miyoshi, Seitaro Terakura, Yasushi Uemura, Knut Woltjen, Yuzo Kodama, Hiroshi Seno, Yasumichi Hitoshi, Tetsuya Nakatsura, Koji Tamada, Shin Kaneko. Enhanced effector responses of regenerated CAR-T cells derived from genome edited iPSCs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1432.

Association of preoperative inflammation-based prognostic score with survival in patients undergoing salvage esophagectomy

Salvage esophagectomy (SALV) is potentially beneficial for patients with residual or relapsed esophageal carcinoma after definitive chemoradiotherapy (dCRT), although preoperatively identifying good candidates for SALV remains difficult. We investigated the prognostic impacts of inflammatory and nutritional status in patients undergoing SALV after dCRT. Forty-seven SALV patients were retrospectively reviewed, of whom 46 (98%) had squamous cell carcinoma and 1 (2%) adenocarcinoma. Possible prognostic factors included patients' demographic data, physical status, blood chemistry profiles, and clinical/pathological tumor features. The Glasgow prognostic score (GPS) was derived from preoperative C-reactive protein (CRP) and albumin values. Thirty (64%), 11 (23%), and 6 (13%) patients were classified into the GPS 0, 1, and 2, respectively, groups. None of the possible prognostic factors showed significant correlations with GPS. Patients with GPS 0 had better outcomes than those with GPS 1 or GPS 2 (Median survivals: 37.8, 15.9, and 5.1 months, respectively, P < 0.001). In the multivariable Cox proportional hazards model, GPS 1 (HR 5.62, 95% CI 1.94-16.4, P = 0.002), GPS 2 (HR 9.10, 95% CI 2.60-31.8, P < 0.001), R1/2 resection (HR 16.3, 95% CI 3.62-86.7, P < 0.001) and incomplete response to dCRT (HR 3.53, 95% CI 1.12-12.5, P = 0.03) were all independent risk factors for a poor outcome. Preoperative GPS is potentially useful for predicting outcomes in esophageal cancer patients undergoing SALV.

Abstract P2-13-02: Patient-reported outcomes with trastuzumab monotherapy versus trastuzumab plus standard chemotherapy as a postoperative adjuvant therapy in HER2-positive elderly breast cancer patients (RESPECT): A randomized, open-label, phase 3 clinical trial

OBJECTIVE: The RESPECT trial compared 1-year trastuzumab monotherapy with trastuzumab plus standard chemotherapy as a postoperative adjuvant therapy in HER2-positive elderly breast cancer patients. Primary objective of this study was to verify the noninferiority of 1-year trastuzumab monotherapy to trastuzumab plus chemotherapy in terms of disease free survival, and the planned analysis showed that the difference of restricted mean survival time between two groups at 3 years was 0.45 months (reported by Sawaki at ASCO2018). This report assesses the patients-reported outcomes and health-related quality of life (HRQoL).

PATIENTS AND METHODS: The study was done at 99 hospitals in Japan. Elderly women (70 to 80 years old) with HER2-positive, stageI-IIIA invasive breast cancer treated by surgery with clear resection margins were randomly assigned to receive either 1-year trastuzumab or 1-year trastuzumab plus standard chemotherapy, stratified by age, hormone-receptor status, pathological lymph node metastasis and institution. Patients completed questionnaires at baseline, 2 months, 1year, and 3 years after protocol treatment started. The primary outcome was global HRQoL assessed using Functional Assessment of Cancer Therapy-General (FACT-G) total score, and secondary outcomes were chemotherapy-induced peripheral neuropathy (CIPN), instrumental activities of daily living (IADL), anxiety, depression, and subjective happiness. We did the analyses by intention to treat, including patients who completed questionnaires at baseline before start of protocol treatment, and 5point or more change is meaningful in FACT-G total score. This study is registered with ClinicalTrials.gov, NCT01104935.

RESULTS: Between Oct 2009 and Oct 2014, 275 patients were enrolled in the study, of whom 9 patients were excluded: 135 assigned to trastuzumab monotherapy and 131 assigned to trastuzumab plus chemotherapy. We detected significant difference between treatment groups for: clinically meaningful HRQoL deterioration rate at 2 months (31% for trastuzumab monotherapy vs 48% for trastuzumab plus chemotherapy; p=0.016) and at 1year (19% vs 38%; p=0.009), clinically meaningful HRQoL improvement rate at 2 months (38% for trastuzumab monotherapy vs 15% for trastuzumab plus chemotherapy; p&lt;0.01) and at 1year (43% vs 25%; p=0.021), severe sensory CIPN rate at 2months (1.9% for trastuzumab monotherapy vs 14.4% for trastuzumab plus chemotherapy; p=0.001), IADL score at 1year (11.97 for trastuzumab monotherapy vs 11.54 for trastuzumab plus chemotherapy; p&lt;0.042), Hospital Anxiety and Depression Scale score at 2months (8.92 for trastuzumab monotherapy vs 10.79 for trastuzumab plus chemotherapy; p&lt;0.003), and subjective happiness score at 1year (12.8 for trastuzumab monotherapy vs 11.8 for trastuzumab plus chemotherapy; p&lt;0.024).

CONCLUSION: Given the small advantage of adjuvant trastuzumab plus chemotherapy compared to trastuzumab monotherapy for elderly HER-2 positive breast cancer women, decisions about treatment should be informed by the risk for adverse health effects associated with chemotherapy.

Citation Format: Kobayashi K, Taira N, Sawaki M, Sagawa N, Baba S, Saito T, Kawahara T, Hagiwara Y, Uemura Y, Shimozuma K, Ohashi Y, Mukai H. Patient-reported outcomes with trastuzumab monotherapy versus trastuzumab plus standard chemotherapy as a postoperative adjuvant therapy in HER2-positive elderly breast cancer patients (RESPECT): A randomized, open-label, phase 3 clinical trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-13-02.

Abstract P1-11-21: Analysis of cognitive function in elderly HER2-positive breast cancer patients receiving either trastuzumab monotherapy or trastuzumab plus chemotherapy as a postoperative adjuvant treatment: A cognitive function sub-study of a randomized, open-label, phase 3 clinical trial (RESPECT trial)

OBJECTIVE: The effect of trastuzumab(Tmab) or chemotherapy on cognitive function has not been fully understood, especially in elderly breast cancer patients. The RESPECT trial compared 1-year(yr) Tmab monotherapy with Tmab plus standard chemotherapy as adjuvant therapy in elderly patients with HER2-positive breast cancer. The primary objective was to verify the noninferiority of 1-yr Tmab monotherapy compared to Tmab plus chemotherapy in terms of disease-free survival, and the planned analysis showed that the difference of restricted mean survival time between two groups at 3 yrs was 0.45 months (Sawaki at ASCO2018). The goal of this report was to assess the impact of the treatment groups on longitudinal cognitive function.

PATIENTS AND METHODS: The study was performed with patients from 99 hospitals in Japan. Elderly women with HER2-positive, stage I-IIIA invasive breast cancer surgery treated with clear resection margins were randomly assigned to either receive 1-yr Tmab or 1-yr Tmab plus standard chemotherapy. 15 institutions participated in the cognitive sub-study. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) at baseline and at 1 and 3 yrs after treatment. The primary outcome was the amount of change in the MMSE score from the baseline. A linear mixed-effects model was used for comparisons of change in the MMSE score between groups, controlling for time and baseline score. Secondary outcomes were the proportion of both suspected mild dementia (MMSE≤27) and dementia (MMSE≤23) at each time point.

RESULTS: Between October 2009 and October 2014, 275 patients were enrolled in the RESPECT trial, and 57 patients were enrolled in the cognitive function sub-study with 2 patients subsequently excluded. The 55-patient sub-study comprised 29 patients assigned to the Tmab monotherapy group and 26 patients assigned to the Tmab plus chemotherapy group. Primary analysis revealed that change in the MMSE score was not significantly different between the two groups (difference −0.6 at 1 yr and −0.9 at 3 yrs; p=0.136), whereas the baseline score was the only significant factor that had an effect on the amount of change in the MMSE score (p&lt;0.001). The proportions of suspected mild dementia at baseline, and at 1 yr and 3 yrs were 15.4, 32.0, and 41.7% in the Tmab monotherapy group, and 45.8, 17.6, and 28.6% in the Tmab plus chemotherapy group. The proportions of suspected mild dementia at baseline were significantly higher in the Tmab plus chemotherapy group (p=0.04). The proportions of suspected dementia at baseline, and at 1 yr and 3 yrs were 0%, 0%, and 4.2% in the Tmab monotherapy group, and 4.2%, 0%, and 4.8% in the Tmab plus chemotherapy group. There were no significant differences in the proportions of suspected dementia between the treatment groups at each time point.

CONCLUSION: Postoperative chemotherapy for elderly breast cancer patients was considered to have little effect on the onset of dementia during the follow-up period of 3 yrs. Further long-term observation is necessary to obtain a significant conclusion.

Citation Format: Takahashi M, Sawaki M, Hagiwara Y, Uemura Y, Kawahara T, Shimozuma K, Ohashi Y, Saito T, Baba S, Kobayashi K, Mukai H, Taira N. Analysis of cognitive function in elderly HER2-positive breast cancer patients receiving either trastuzumab monotherapy or trastuzumab plus chemotherapy as a postoperative adjuvant treatment: A cognitive function sub-study of a randomized, open-label, phase 3 clinical trial (RESPECT trial) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-11-21.

Abstract P1-14-07: Randomized phase 3 study of anthracycline-containing regimens versus S-1 as first-line treatment for metastatic breast cancer (SELECT BC-CONFIRM)–A combined analysis of two randomized phase 3 studies (SELECT BC-CONFIRM and SELECT BC)–

Background: Anthracycline-containing regimens and taxane have been standard as the first-line chemotherapy for metastatic breast cancer (MBC). We conducted SELECT BC (randomized phase 3 study of taxane versus S-1 as first-line treatment for MBC) for evaluating the efficacy of S-1 for patients with HER2-negative MBC from 2006 to 2010 in Japan. This study demonstrated non-inferiority of S-1 in overall survival (OS) (median OS was 37.2 months in taxes group and 35.0 months in S-1 group (HR 1.05, 95% CI 0.86–1.27, p=0.015)), and superiority in health-related quality of life (HRQOL) to taxanes. S-1 was also shown as less toxic than taxane (Lancet Oncol 2016; 17: 90-98). S-1 might provide clinical benefit as first-line treatment for patients with HER2-negative MBC. To confirm this suggestion, we have conducted further study (randomized phase 3 study of anthracycline-containing regimens versus S-1 as first-line treatment for HER2-negative MBC: SELECT BC-CONFIRM) from 2011 to present, and a combined analysis of two randomized studies (SELECT-BC CONFIRM and SELECT-BC).

Methods: In SELECT BC-CONFIRM, 230 patients receiving first-line treatment for MBC were randomly assigned to either anthracycline group (n=115) or S-1 group (n=115). Anthracycline group patients received anthracycline-containing regimens (AC, EC, FAC, FEC, q3w) at the discretion of the treating physician. S-1 group patients received S-1 40–60 mg twice daily based on the patient's body surface area for 28 days on, 14-day off. The primary endpoint was OS, and secondary endpoints were progression-free survival (PFS), time to treatment failure (TTF), adverse events, HRQOL, and cost-effectiveness. The results were combined with SELECT-BC, to confirm the hypothesis that S-1 treatment is not inferior to the standard therapy (taxanes / anthracycline) for HER2-negative MBC.

Results: A combined analysis of the two studies showed that HR was 1.06, 95%CI 0.90-1.253, and p=0.0071 between the standard therapy group and S-1 group. In addition, the Bayesian posterior probability for which HR would be less than 1.333 was about 99.6%.

Conclusions: A combined analysis of SELECT BC-CONFIRM and SELECT BC clearly demonstrated that OS with S-1 was not inferior to that with the standard therapy in patients receiving first-line treatment for HER2-negative MBC. S-1 could become a standard therapy for this patient population.

Citation Format: Park Y, Akabane H, Watanabe T, Takahashi M, Sagara Y, Nishimura R, Tsurutani J, Takashima T, Fujisawa T, Hozumi Y, Uemura Y, Mukai H. Randomized phase 3 study of anthracycline-containing regimens versus S-1 as first-line treatment for metastatic breast cancer (SELECT BC-CONFIRM)–A combined analysis of two randomized phase 3 studies (SELECT BC-CONFIRM and SELECT BC)– [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-14-07.

Enhancing T Cell Receptor Stability in Rejuvenated iPSC-Derived T Cells Improves Their Use in Cancer Immunotherapy

Limited T cell availability and proliferative exhaustion present major barriers to successful T cell-based immunotherapies and may potentially be overcome through the use of "rejuvenated" induced pluripotent stem cells derived from antigen-specific T cells (T-iPSCs). However, strict antigen specificity is essential for safe and efficient T cell immunotherapy. Here, we report that CD8αβ T cells from human T-iPSCs lose their antigen specificity through additional rearrangement of the T cell receptor (TCR) α chain gene during the CD4/CD8 double positive stage of in vitro differentiation. CRISPR knockout of a recombinase gene in the T-iPSCs prevented this additional TCR rearrangement. Moreover, when CD8αβ T cells were differentiated from monocyte-derived iPSCs that were transduced with an antigen-specific TCR, they showed monoclonal expression of the transduced TCR. TCR-stabilized, regenerated CD8αβ T cells effectively inhibit tumor growth in xenograft cancer models. These approaches could contribute to safe and effective regenerative T cell immunotherapies.

Abstract 2550: Generation of CAR-iPS-T cells expressing CD8β

Chimeric antigen receptor (CAR) is an artificial protein that provides HLA-independent antigen specificity to T cells. CAR-T therapy has shown remarkable clinical responses especially in hematologic malignancies. But this therapy needs cell preparation for each patient. That limits its applicability. We have reported regeneration of T cells from iPSCs (Cell Stem Cell 2013). This technology provides unlimited number of T cells, so CAR-T therapy using iPSCs can broadens its applicability. Regenerated T cells previously described in some reports including ours have some different characters from peripheral T cells. In particular, they express only CD8α, and do not express CD8β. We successfully generate CAR-iPS-T cells expressing CD8β with some modification of differentiation protocols. We assayed the function of CAR-iPS-T cells in view of the difference between CD8β positive and negative iPS-T cells. We found CD8β positive CAR-iPS-T cells showed enhanced function to suppress tumor progression compared with CD8β negative CAR-iPS-T cells in subcutaneous xenograft model. In vivo kinetics study revealed that CD8β positive CAR-iPS-T cells have superior function to traffic to target expressing tumor site and enhanced sustainability in vivo compared with CD8β negative CAR-iPS-T cells. These findings indicate that CD8β positive CAR-iPS-T cells may be a potent cell source for iPSC-based cancer immunotherapy.

Citation Format: Tatsuki Ueda, Shoichi Iriguchi, Yohei Kawai, Atsutaka Minagawa, Hiroyuki Miyoshi, Seitaro Terakura, Yasushi Uemura, Knut Woltjen, Yuzo Kodama, Hiroshi Seno, Yasumichi Hitoshi, Tetsuya Nakatsura, Koji Tamada, Shin Kaneko. Generation of CAR-iPS-T cells expressing CD8β [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2550.

Abstract 3585: T cell receptor-stabilized regenerated CD8ab cytotoxic T lymphocytes for cancer immunotherapy

The use of antigen-specific T cell derived induced iPSCs as a cell source for regeneration of cytotoxic T lymphocytes (CTLs) have advantages in rejuvenation profile, and reproducible number of CTLs. However for the safe and efficient regenerated T cell immunotherapy, strict antigen specificity is essential. Here we report CD8αβ T cells differentiated from T cell-derived iPSCs underwent additional rearrangement of the T cell receptor (TCR) α-chain gene at the CD4/CD8 double positive stage during in vitro differentiation and lost antigen specificity. CRISPR knockout of a recombinase gene in the T-iPSCs successfully prevented this additional TCR rearrangement. Moreover, when CD8αβ T cells were differentiated from non-T cell-derived but antigen-specific TCR-transduced iPSCs, they showed monoclonal expression of the transduced TCR. TCR stabilized regenerated CD8αβ T cells effectively inhibit tumor growth in xenograft cancer models. These approaches could contribute to safe and effective regenerative T cell immunotherapies.

Citation Format: Atsutaka Minagawa, Akitsu Hotta, Yohei Kawai, Yutaka Yasui, Yasushi Uemura, Masaki Yasukawa, Tetsuya Nakatsura, Shin Kaneko. T cell receptor-stabilized regenerated CD8ab cytotoxic T lymphocytes for cancer immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3585.

Inhibition of Tissue Activator by Urokinase Inhibitor

Inhibition of tissue activator purified from human heart by urokinase inhibitor purified from human placenta was observed by both the fibrin plate method and fibrin clot lysis time method. It was shown to be of much less on extent in comparison with urokinase, that is, 20 Ploug units of urokinase were completely inhibited by approximately 100 or 200 u of urokinase inhibitor in the respective methods but 6 Ploug units of tissue activator were inhibited only 25% to 50% even though 1,000 u of urokinase inhibitor were used.

Generation of TCR-Expressing Innate Lymphoid-like Helper Cells that Induce Cytotoxic T Cell-Mediated Anti-leukemic Cell Response

CD4⁺ T helper (Th) cell activation is essential for inducing cytotoxic T lymphocyte (CTL) responses against malignancy. We reprogrammed a Th clone specific for chronic myelogenous leukemia (CML)-derived b3a2 peptide to pluripotency and re-differentiated the cells into original TCR-expressing T-lineage cells (iPS-T cells) with gene expression patterns resembling those of group 1 innate lymphoid cells. CD4 gene transduction into iPS-T cells enhanced b3a2 peptide-specific responses via b3a2 peptide-specific TCR. iPS-T cells upregulated CD40 ligand (CD40L) expression in response to interleukin-2 and interleukin-15. In the presence of Wilms tumor 1 (WT1) peptide, antigen-specific dendritic cells (DCs) conditioned by CD4-modified CD40L^high iPS-T cells stimulated WT1-specific CTL priming, which eliminated WT1 peptide-expressing CML cells in vitro and in vivo. Thus, CD4 modification of CD40L^high iPS-T cells generates innate lymphoid helper-like cells inducing bcr-abl-specific TCR signaling that mediates effectiveanti-leukemic CTL responses via DC maturation, showing potential for adjuvant immunotherapy against leukemia.

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iPSC-derived T cells have molecular similarity to group 1 innate lymphoid cells

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iPSC-derived CD40L^high T cell-adjuvants induce leukemia-specific CTLs via DCs

Oral mass revealing Chédiak-Higashi syndrome

This case report describes common oral inflammatory findings leading to the identification of Chédiak-Higashi syndrome (CHS). A 15-year-old girl presented with an enlarging and painful mass on the upper lip. Two weeks after the initial visit, the mass showed further protrusion in the absence of fever. Magnetic resonance imaging revealed a well-circumscribed cystic lesion with a thick capsule, and suggested an abscess derived from the mucous cyst in the upper lip. Inflammation indices were not elevated; however neutrophils were significantly lower than the normal level. Giant cytoplasmic granules in neutrophils, eosinophils, and lymphocytes, which are pathognomonic of CHS, were noted. The patient displayed brownish-red hair with some grey hair, and partial oculocutaneous albinism. Hepatosplenomegaly was evident on ultrasonography. The final diagnosis was of an oral infection facilitated by the adolescent form of CHS (gene CHS1/LYST at 1q42.1-2). This report offers a reminder that lip swelling may represent the initial manifestation of the inflammatory response in a patient with loss of immunocompetence due to pathologies such as CHS, and may rarely present as the patient's main complaint.

Abstract P4-21-03: A randomized phase II study of Ki-67 response-guided preoperative chemotherapy for HER2-positive breast cancer

As for the HER2-positive breast cancer, there are many cases to be effective for neoadjuvant chemotherapy in comparison with other intrinsic subtypes. However, pCR is not provided by neoadjuvant chemotherapy in all cases. [Aim] This study evaluated the effectiveness of a therapeutic strategy that switches chemotherapy, based on Ki-67 tumor expression after initial therapy, relative to that of standard chemotherapy in patients with HER2-positive breast cancer. [patients and methods] Patients were randomly assigned to the control arm or the Ki-67 response-guided arm (Ki-67 arm). Primary tumor biopsies were obtained before treatment, and after three once-weekly doses of paclitaxel and trastuzumab to assess the interim Ki-67 index. In the control arm, paclitaxel and trastuzumab was continued for a total of 12 doses, regardless of the interim Ki-67 index. In the Ki-67 arm, subsequent treatment was based on the interim Ki-67 index. Early Ki-67 responders continued to received paclitaxel plus trastuzumab for a total of 12 doses, while early Ki-67 non-responders were switched to epirubicin plus cyclophosphamide every 3 weeks for three cycles with once-weekly trastuzumab for a total of 12 doses. The primary endpoint was the pathological complete response (pCR) rate. [Results] When 237 patients were enrolled, an interim analysis was conducted in 200 patients. There was almost linear correlation between the Ki-67 reduction rate at interim assessment and the pCR rate. The pCR rate in Ki-67 early non-responders in the Ki-67 arm (23.6%; 95% CI, 12.4 to 34.9) was inferior to that in the control arm (44.1%; 31.4 to 56.7; p=0.025). A strong correlation was not found between the Ki-67 reduction rate and the clinical response rate (Spearman's correlation coefficient 0.22).

pCR rate among Ki-67 early non-responders and responders TotalpCR nn%95%CIKi-67 early non responderControl arm59264431.4-56.7 Ki-67 response guided arm55132312.4-34.9Ki-67 early responderControl arm21104726.3-69.0 Ki-67 response guided arm2084018.5-61.5

Conclusions: The pCR rate in the Ki-67 arm was inferior to that in the control arm. A therapeutic strategy that switches chemotherapy, based on Ki-67 tumor expression after initial therapy, was not effective. The standard chemotherapy protocol remains as the recommended strategy for patients with HER2-positive breast cancer.

Citation Format: Takahashi M, Nishiyama Y, Hara F, Naito Y, Baba M, Sasaki M, Sato M, Watanabe K, Uemura Y, Yamaguchi T, Mukai H. A randomized phase II study of Ki-67 response-guided preoperative chemotherapy for HER2-positive breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-03.

Cellular Adjuvant Properties, Direct Cytotoxicity of Re-differentiated Vα24 Invariant NKT-like Cells from Human Induced Pluripotent Stem Cells

Vα24 invariant natural killer T (iNKT) cells are a subset of T lymphocytes implicated in the regulation of broad immune responses. They recognize lipid antigens presented by CD1d on antigen-presenting cells and induce both innate and adaptive immune responses, which enhance effective immunity against cancer. Conversely, reduced iNKT cell numbers and function have been observed in many patients with cancer. To recover these numbers, we reprogrammed human iNKT cells to pluripotency and then re-differentiated them into regenerated iNKT cells in vitro through an IL-7/IL-15-based optimized cytokine combination. The re-differentiated iNKT cells showed proliferation and IFN-γ production in response to α-galactosylceramide, induced dendritic cell maturation and downstream activation of both cytotoxic T lymphocytes and NK cells, and exhibited NKG2D- and DNAM-1-mediated NK cell-like cytotoxicity against cancer cell lines. The immunological features of re-differentiated iNKT cells and their unlimited availability from induced pluripotent stem cells offer a potentially effective immunotherapy against cancer.

Clinical assessment and prevalence of parkinsonism in Japanese elderly people

BACKGROUND

Parkinsonism is often observed in the elderly. To clarify the prevalence of parkinsonism-associated diseases and conditions, we conducted a population-based study in a rural island town in western Japan, Ama-cho.

METHODS

Participants included 924 subjects aged 65 years or older residing in the town. Between 2008 and 2011, participants were assessed via standardized neurological examination scales, and Brain MRIs were carried out in 2010. Based on the results of assessment using the modified Unified Parkinson's Disease Rating Scale and a standardized neurological examination, participants were diagnosed as having parkinsonism or mild parkinsonian signs (MPS), or as displaying normal motor conditions (M-normal).

RESULTS

Of the 729 participants screened, 70 subjects were diagnosed as having parkinsonism, corresponding to a crude prevalence rate of 9.6% (95% CI, 7.9-11.3%), while 167 MPS subjects (22.9%) and 492 subjects experiencing M-normal (67.5%) were observed. Parkinsonism was found in association with various diseases such as Vascular parkinsonism, Lewy body disease, Alzheimer's disease (AD), and idiopathic normal-pressure hydrocephalus. Among the subjects with dementia, the proportion with parkinsonism was higher in the non-AD dementia group.

CONCLUSION(S)

Parkinsonism occurs in association with several diseases in elderly people. Parkinsonism was also found to be commonly associated with cognitive impairment.

Prospectively Isolated Human Bone Marrow Cell-Derived MSCs Support Primitive Human CD34-Negative Hematopoietic Stem Cells

Hematopoietic stem cells (HSCs) are maintained in a specialized bone marrow (BM) niche, which consists of osteoblasts, endothelial cells, and a variety of mesenchymal stem/stromal cells (MSCs). However, precisely what types of MSCs support human HSCs in the BM remain to be elucidated because of their heterogeneity. In this study, we succeeded in prospectively isolating/establishing three types of MSCs from human BM-derived lineage- and CD45-negative cells, according to their cell surface expression of CD271 and stage-specific embryonic antigen (SSEA)-4. Among them, the MSCs established from the Lineage(-) CD45(-) CD271(+) SSEA-4(+) fraction (DP MSC) could differentiate into osteoblasts and chondrocytes, but they lacked adipogenic differentiation potential. The DP MSCs expressed significantly higher levels of well-characterized HSC-supportive genes, including IGF-2, Wnt3a, Jagged1, TGFβ3, nestin, CXCL12, and Foxc1, compared with other MSCs. Interestingly, these osteo-chondrogenic DP MSCs possessed the ability to support cord blood-derived primitive human CD34-negative severe combined immunodeficiency-repopulating cells. The HSC-supportive actions of DP MSCs were partially carried out by soluble factors, including IGF-2, Wnt3a, and Jagged1. Moreover, contact between DP MSCs and CD34-positive (CD34(+) ) as well as CD34-negative (CD34(-) ) HSCs was important for the support/maintenance of the CD34(+/-) HSCs in vitro. These data suggest that DP MSCs might play an important role in the maintenance of human primitive HSCs in the BM niche. Therefore, the establishment of DP MSCs provides a new tool for the elucidation of the human HSC/niche interaction in vitro as well as in vivo.

Enhancement of antitumor effect by peptide vaccine therapy in combination with anti-CD4 antibody: Study in a murine model

Purpose

The clinical efficacy of cancer peptide vaccine therapy is insufficient. To enhance the anti-tumor effect of peptide vaccine therapy, we combined this therapy with an anti-CD4 mAb (GK1.5), which is known to deplete CD4⁺ cells, including regulatory T cells (Tregs).

Methods

To determine the treatment schedule, the number of lymphocyte subsets in the peripheral blood of mice was traced by flow cytometry after administration of anti-CD4 mAb. The ovalbumin (OVA)_257–264 peptide vaccine was injected intradermally and anti-CD4 mAb was administered intraperitoneally into C57BL/6 mice at different schedules. We evaluated the enhancement of OVA peptide-specific cytotoxic T lymphocyte (CTL) induction in the combination therapy using the ELISPOT assay, CD107a assay, and cytokine assay. We then examined the in vivo metastasis inhibitory effect by OVA peptide vaccine therapy in combination with anti-CD4 mAb against OVA-expressing thymoma (EG7) in a murine liver metastatic model.

Results

We showed that peptide-specific CTL induction was enhanced by the peptide vaccine in combination with anti-CD4 mAb and that the optimized treatment schedule had the strongest induction effect of peptide-specific CTLs using an IFN-γ ELISPOT assay. We also confirmed that the CD107a⁺ cells secreted perforin and granzyme B and the amount of IL-2 and TNF produced by these CTLs increased when the peptide vaccine was combined with anti-CD4 mAb. Furthermore, metastasis was inhibited by peptide vaccines in combination with anti-CD4 mAb compared to peptide vaccine alone in a murine liver metastatic model.

Conclusion

The use of anti-CD4 mAb in combination with the OVA peptide vaccine therapy increased the number of peptide-specific CTLs and showed a higher therapeutic effect against OVA-expressing tumors. The combination with anti-CD4 mAb may provide a new cancer vaccine strategy.

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Peptide-specific CTL induction and function were enhanced by depletion of CD4⁺ cells.

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Anti-tumor effect by the peptide vaccine was enhanced by the depletion of CD4⁺ cells.

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Metastasis was inhibited by vaccine with depletion of CD4⁺ cells in a murine model.

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Combination with the depletion of CD4⁺ cells could be a new cancer vaccine strategy.

Hepatocellular carcinoma cell sensitivity to Vγ9Vδ2 T lymphocyte-mediated killing is increased by zoledronate

The limited efficacy of vaccines in hepatocellular carcinoma (HCC), due to the low frequency of tumor-infiltrating cytotoxic T lymphocytes (CTLs), indicates the importance of innate immune surveillance, which assists acquired immunity by directly recognizing and eliminating HCC. Innate Vγ9Vδ2 T cells have major histocompatibility complex-unrestricted antitumor activity and are activated by phosphoantigens, which are upregulated in cancer cells by the nitrogen-containing bisphosphonate, zoledronate (Zol). A better understanding of HCC susceptibility to Zol and downstream γδ T cell-mediated killing is essential to optimize γδ T cell-mediated immunotherapy. This study systematically examined the interactions between γδ T cells and Zol-treated HCC cell lines (HepG2, HLE, HLF, HuH-1, JHH5, JHH7, and Li-7) in vitro. All HCC cell lines expressed the DNAX accessory molecule-1 ligands, poliovirus receptor, and Nectin-2, and γδ T cell-mediated killing of these cells was significantly enhanced by Zol. Small interfering RNA-mediated knockdown of these ligands did not affect the susceptibility to γδ T cell lysis. This killing activity was partly inhibited by mevastatin, an inhibitor of the mevalonate pathway, and markedly reduced by a monoclonal antibody to γ- and δ-chain T cell receptor, indicating that this is crucial for Zol-induced HCC killing. In addition, Zol-treated HCC cell lines triggered γδ T cell proliferation and induced production of Th1 and Th2, but not Th17, cytokines. The Zol concentration that enhanced HCC cell susceptibility to γδ T cell killing was lower than that required to directly inhibit HCC proliferation. Thus, γδ T cells may be important effector cells in the presence of Zol, especially where there are insufficient number of cancer antigen-specific CTLs to eliminate HCC. Our in vitro data support the proposal that Zol-treatment, combined with adaptive γδ T cell immunotherapy, may provide a feasible and effective approach for treatment of HCC.

Abstract P5-18-01: A randomized clinical trial of postoperative adjuvant therapy for elderly breast cancer patients: Conditions of obtaining informed consent and reasons for declining participation

Background: There are few randomized clinical trials examining adjuvant treatment in elderly breast cancer patients. While obtaining informed consent is essential for participation in clinical studies, there is little information on the frequency of agreement to participate among elderly patients. Furthermore, elderly patients might have specific reasons to decline participation.

Patients and Method: The National Surgical Adjuvant Study of Breast Cancer 07 (N-SAS BC 07) is a randomized clinical trial in women over 70 years with HER2-positive primary breast cancer. The primary aim was to investigate the benefit of trastuzumab monotherapy compared with the combination of trastuzumab and chemotherapy. Key inclusion criteria were as follows: women between 70 and 80 years old with HER2-positive breast cancer; underwent curative operation; stage I to IIIA; with sufficient organ function. Patients were randomized to receive either trastuzumab plus chemotherapy or trastuzumab monotherapy. The primary endpoint was disease-free survival, and the secondary endpoints were overall survival, relapse-free survival, safety, health-related quality of life, and cost effectiveness (NCT01104935). It was not possible to predict the number of patients who would agree to participate. In order to comprehensively assess the effect of postoperative adjuvant therapy, we evaluated the reasons why eligible patients declined to participate. The patients were registered in a cohort study to prospectively evaluate the subsequent treatment options and prognosis (07-Cohort). This study examined the obtaining of informed consent for N-SAS BC 07 and the reasons for declining participation, and compared the clinicopathological backgrounds between the N-SAS BC 07 and 07-Cohort groups.

Results: 398 eligible patients have been recruited. Informed consent to participate in N-SAS BC 07 has been obtained from 275 patients (69%) and 123 patients (31%) who declined to participate in the RCT have been registered in the 07-Cohort. The common reasons to decline participation in the RCT were "cannot choose the treatment option (55%)", "refused chemotherapy (16%)", "wanted chemotherapy (9%)", "anxious about clinical studies (9%)" and "family opposition (8%)". The mean ages of the patients in N-SAS BC 07 and 07-Cohort were 73.9 and 74.6 years old, respectively. There were no differences in stage, surgical procedure, lymph node metastasis, or co-morbidities between the groups. ER-positive rate was higher in 07-Cohort group compared with N-SAS BC 07 group (53% vs. 37%, p=0.017, χ2 test).

Conclusion: While we expected the number of registrants to be small, since N-SAS BC 07 investigated whether elderly patients with HER2-positive breast cancer should undergo chemotherapy, almost 70% of the patients accepted informed consent. The most common reason to decline participation in N-SAS BC 07 was "cannot choose the treatment option" and the majority refused chemotherapy. Furthermore, ER-positivity was higher in the 07-Cohort group, which suggested that ER expression in the patients with HER2-positive breast cancer might influence their decision to participate in the study or to choose the treatment option.

Citation Format: Sagara Y, Sawaki M, Taira N, Saito T, Kashiwaba M, Iwata H, Kobayashi K, Nakayama T, Bando H, Mizuno T, Yamamoto Y, Tsuneizumi M, Takahashi M, Yamaguchi M, Kawashima H, Takashima T, Uemura Y, Hozumi Y, Sagawa N, Mukai H, Ohashi Y. A randomized clinical trial of postoperative adjuvant therapy for elderly breast cancer patients: Conditions of obtaining informed consent and reasons for declining participation. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-18-01.

Abstract P4-11-09: A randomized controlled trial of postoperative adjuvant therapy for elderly breast cancer patients: Comparison of health-related quality of life between clinical trial participants and decliners

Background: Health-related quality of life (HRQoL) is one of the important outcomes in cancer control trials and has increasingly become the one of the primary foci. Obtaining informed consent from participants is essential for participation in randomized controlled trials (RCTs), but the participation in these RCTs may directly influence HRQoL, because treatment options are determined according to the allocation schedule. To date, only a few studies have compared HRQoL between clinical trial participants and decliners.

Patients and Method: The National Surgical Adjuvant Study of Breast Cancer 07 (N-SAS BC 07) is a randomized controlled trial in women with HER2-positive primary breast cancer who are over 70 years of age. The primary aim was to investigate the benefit of trastuzumab monotherapy compared with combination therapy using trastuzumab and chemotherapy. The study concept and design were published in concept paper (Sawaki M. et al., Jpn J Clin Oncol. 2011). In this study, patients were randomized to receive either trastuzumab plus chemotherapy or trastuzumab monotherapy. The primary endpoint was disease-free survival, and the secondary endpoints were overall survival, relapse-free survival, safety, HRQoL, comprehensive geriatric assessment (CGA) and cost effectiveness (protocol ID; NCT01104935).

HRQoL and CGA were assessed at registration (baseline), 2 month, 1 year, and 3 years after the start of protocol treatments using the Functional Assessment of Cancer Therapy-General (FACT-G), Hospital Anxiety and Depression Scale (HADS), EuroQol 5 Dimension (EQ-5D), Tokyo Metropolitan Institute of Gerontology (TMIG) index of competence, and the Philadelphia Geriatric Center (PGC) Morale Scale.

The patients who declined to participate in N-SAS BC 07 were registered in a cohort study to prospectively evaluate the subsequent treatment options and prognosis (07-Cohort). The same questionnaire that was used in N-SAS BC 07 was used in 07-Cohort to evaluate HRQoL and CGA at entry.

Results: Patients were enrolled from October 2012 to October 2016. During this period, 275 and 123 patients were registered in N-SAS BC 07 and 07-Cohort, respectively. The mean age at entry of the patients in the N-SAS BC 07 and 07-Cohort groups was 73.9 and 74.6 years, respectively. The questionnaire response rates at baseline in the patients in N-SAS BC 07 and 07-Cohort groups were 89% and 82%, respectively. There were no significant differences in FACT-G, HADS, EQ-5D, or TMIG index of competence at baseline between the groups, but the mean (standard deviation) scores of PGC Morale Scale in N-SAS BC 07 and 07-Cohort groups were 10.8 (3.3) and 9.9 (3.7), respectively, with the scores being significantly greater in the N-SAS BC 07 group (p=0.020, t-test).

Conclusion: The PGC Morale Scale provides a multidimensional approach to assess the psychological state of older people. This study indicated that participation in the RCT did not affect the baseline QoL of elderly patients but suggested that the baseline QoL of the RCT participants was better than decliners.

Citation Format: Saito T, Sawaki M, Hozumi Y, Sagawa N, Iwata H, Kashiwaba M, Kawashima H, Kobayashi K, Taira N, Takashima T, Takahashi M, Tsuneizumi M, Nakayama T, Baba S, Bando H, Mizuno T, Yamaguchi M, Yamamoto Y, Uemura Y, Ohashi Y, Mukai H. A randomized controlled trial of postoperative adjuvant therapy for elderly breast cancer patients: Comparison of health-related quality of life between clinical trial participants and decliners. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-11-09.

Vaccination with liposome-coupled glypican-3-derived epitope peptide stimulates cytotoxic T lymphocytes and inhibits GPC3-expressing tumor growth in mice

Because therapeutic manipulation of immunity can induce tumor regression, anti-cancer immunotherapy is considered a promising treatment modality. We previously reported that glypican-3 (GPC3), an oncofetal antigen overexpressed in hepatocellular carcinoma (HCC), is a useful target for cytotoxic T lymphocyte (CTL)-mediated cancer immunotherapy, and we have performed clinical trials using the GPC3-derived peptide vaccine. Although vaccine-induced GPC3-peptide-specific CTLs were often tumor reactive in vitro and were correlated with overall survival, no complete response was observed. In the current study, we synthesized liposome-coupled GPC3-derived CTL epitope peptide (pGPC3-lipsome) and investigated its antitumor potential. Vaccination with pGPC3-liposome induced peptide-specific CTLs at a lower dose than conventional vaccine emulsified in incomplete Freund's adjuvant. Coupling of pGPC3 to liposomes was essential for effective priming of GPC3-specific CTLs. In addition, immunization with pGPC3-liposome inhibited GPC3-expressing tumor growth. Thus, vaccination with tumor-associated antigen-derived epitope peptides coupled to the surfaces of liposomes may be a novel therapeutic strategy for cancer.

Identification and Characterization of Lineage(-)CD45(-)Sca-1(+) VSEL Phenotypic Cells Residing in Adult Mouse Bone Tissue

Murine bone marrow (BM)-derived very small embryonic-like stem cells (BM VSELs), defined by a lineage-negative (Lin(-)), CD45-negative (CD45(-)), Sca-1-positive (Sca-1(+)) immunophenotype, were previously reported as postnatal pluripotent stem cells (SCs). We developed a highly efficient method for isolating Lin(-)CD45(-)Sca-1(+) small cells using enzymatic treatment of murine bone. We designated these cells as bone-derived VSELs (BD VSELs). The incidences of BM VSELs in the BM-derived nucleated cells and that of BD VSELs in bone-derived nucleated cells were 0.002% and 0.15%, respectively. These BD VSELs expressed a variety of hematopoietic stem cell (HSC), mesenchymal stem cell (MSC), and endothelial cell markers. The gene expression profile of the BD VSELs was clearly distinct from those of HSCs, MSCs, and ES cells. In the steady state, the BD VSELs proliferated slowly, however, the number of BD VSELs significantly increased in the bone after acute liver injury. Moreover, green fluorescent protein-mouse derived BD VSELs transplanted via tail vein injection after acute liver injury were detected in the liver parenchyma of recipient mice. Immunohistological analyses suggested that these BD VSELs might transdifferentiate into hepatocytes. This study demonstrated that the majority of the Lin(-)CD45(-)Sca-1(+) VSEL phenotypic cells reside in the bone rather than the BM. However, the immunophenotype and the gene expression profile of BD VSELs were clearly different from those of other types of SCs, including BM VSELs, MSCs, HSCs, and ES cells. Further studies will therefore be required to elucidate their cellular and/or SC characteristics and the potential relationship between BD VSELs and BM VSELs.