Unusually strong electronic correlation and field-induced ordered phase in YbCo2

We report the first study of electrical resistivity, magnetization, and specific heat on YbCo₂. The measurements on a single-phased sample of YbCo₂bring no evidence of magnetic ordering down to 0.3 K in a zero magnetic field. The manifestations of low Kondo temperature are observed. The specific heat value divided by temperature,C/T, keeps increasing logarithmically beyond 7 J/mol K²with decreasing temperature down to 0.3 K without no sign of magnetic ordering, suggesting a very large electronic specific heat. Analysis of the magnetic specific heat indicates that the large portion of the low-temperature specific heat is not explained simply by the low Kondo temperature but is due to the strong intersite magnetic correlation in both the 3dand 4felectrons. Temperature-dependent measurements under static magnetic fields up to 7 T are carried out, which show the evolution of field-induced transition above 2 T. The transition temperature increases with increasing field, pointing to a ferromagnetic character. The extrapolation of the transition temperature to zero field suggests that YbCo₂is in the very proximity of the quantum critical point. These results indicate that in the unique case of YbCo₂, the itinerant electron magnetism of Co 3d-electrons and the Kondo effect within the vicinity of quantum criticality of Yb 4f-local moments can both play a role.

DSP-0509, a systemically available TLR7 agonist, exhibits combination effect with immune checkpoint blockade by activating anti-tumor immune effects

TLR7 is an innate immune receptor that recognizes single-stranded RNAs, and its activation leads to anti-tumor immune effects. Although it is the only approved TLR7 agonist in cancer therapy, imiquimod is allowed to be administered with topical formulation. Thus, systemic administrative TLR7 agonist is expected in terms of expanding applicable cancer types. Here, we demonstrated the identification and characterization of DSP-0509 as a novel small-molecule TLR7 agonist. DSP-0509 is designed to have unique physicochemical features that could be administered systemically with a short half-life. DSP-0509 activated bone marrow-derived dendritic cells (BMDCs) and induced inflammatory cytokines including type I interferons. In the LM8 tumor-bearing mouse model, DSP-0509 reduced tumor growth not only in subcutaneous primary lesions but also in lung metastatic lesions. DSP-0509 inhibited tumor growth in several syngeneic tumor-bearing mouse models. We found that the CD8⁺ T cell infiltration of tumor before treatment tended to be positively correlated with anti-tumor efficacy in several mouse tumor models. The combination of DSP-0509 with anti-PD-1 antibody significantly enhanced the tumor growth inhibition compared to each monotherapy in CT26 model mice. In addition, the effector memory T cells were expanded in both the peripheral blood and tumor, and rejection of tumor re-challenge occurred in the combination group. Moreover, synergistic anti-tumor efficacy and effector memory T cell upregulation were also observed for the combination with anti-CTLA-4 antibody. The analysis of the tumor-immune microenvironment by using the nCounter assay revealed that the combination of DSP-0509 with anti-PD-1 antibody enhanced infiltration by multiple immune cells including cytotoxic T cells. In addition, the T cell function pathway and antigen presentation pathway were activated in the combination group. We confirmed that DSP-0509 enhanced the anti-tumor immune effects of anti-PD-1 antibody by inducing type I interferons via activation of dendritic cells and even CTLs. In conclusion, we expect that DSP-0509, a new TLR7 agonist that synergistically induces anti-tumor effector memory T cells with immune checkpoint blockers (ICBs) and can be administered systemically, will be used in the treatment of multiple cancers.

COT-18 DATABASE STUDY ON TRENDS IN MEDICAL EXAMINATIONS OF PATIENTS WITH MALIGNANT BRAIN TUMORS

Background and Purpose

Glioblastoma is the most is the poorest prognosis tumor of all carcinomas. Various factors contribute to deterioration for glioblastoma such as age, KPS, and surgical removal level. The most important factors for poor prognosis are that half of patients with glioblastoma have a KPS ≤ 70 at the start of treatment because glioblastoma progresses rapidly. There have been no comprehensive reports on the trends in visits and time to initiation of treatment for patients with glioblastoma. We analyzed the actual clinical course of malignant brain tumor patients using the receipt database with the aim of raising awareness of prompt diagnosis and treatment.

Methods

Because this study included patient-visit transitions, we utilized receipt data from JMDC Inc., which can be tracked through changes of medical facilities. We analyzed for data for the period January 1, 2005, to March 31, 2022.

Results and Discussion

The study included 493 patients with malignant neoplasms of brain, aged 18 years or older, who underwent surgery and received radiation or temozolomide. The medical departments that visited for the first time before surgery were general internal medicine, neurosurgery, followed by ophthalmologist, orthopedics, and otolaryngology. The period from the date of the first visit to surgery was 21 days for neurosurgery and 46 days for general internal medicine. The mean time from MRI to surgery was 11 days when surgery was performed at the MRI site, and 22 days when the patient was referred to another hospital after MRI. This study clarified the actual situation when patients with malignant brain tumors visit a department besides neurosurgery. In order to facilitate prompt diagnosis and treatment, it is necessary to raise awareness of the disease among the departments where patients are likely to visit for the first time.

Comprehensive analysis of protein-expression changes specific to immunoglobulin G4-related disease

BACKGROUND AND AIMS

Immunoglobulin 4 (IgG4)-related disease (IgG4-RD) is a lymphoproliferative disorder characterized by elevated serum IgG4 levels and tissue infiltration of IgG4-positive plasma cells. We analyzed the serum proteins, whose levels varied based on the disease state and treatment.

MATERIALS AND METHODS

Serum proteins from patients with IgG4-related disease and healthy subjects were resolved using two-dimensional electrophoresis, silver-stained, and scanned. Alternatively, the proteins were labeled with Cy2, Cy3, and Cy5 before electrophoresis. The proteins, whose expression differed significantly between patients and healthy individuals, and between before and after steroid treatment, were identified and validated using enzyme-linked immunosorbent assays.

RESULTS

Pre-treatment sera from patients with IgG4-related disease was characterized by increased levels of immunoglobulins such as IgG1, IgG4; inflammatory factors such as α-1 antitrypsin (A1AT); and proteins associated with immune system regulation such as clusterin and leucine-rich α-2-glycoprotein (LRG-1). The serum levels of A1AT, LRG-1 and clusterin, during treatment with prednisolone for up to 12 months revealed that LRG-1 levels were halved after 1 month of treatment, comparable to those in healthy subjects; LRG-1 levels remained normal until the end of treatment.

CONCLUSION

LRG-1 could serve as a novel biomarker of IgG4-related diseases.

Interlaboratory Evaluation of Two Enzyme-Linked Immunosorbent Assay Kits for the Determination of Crustacean Protein in Processed Foods

The labeling of foods containing material derived from crustaceans such as shrimp and crab is to become mandatory in Japan because of increases in the number of allergy patients. To ensure proper labeling, 2 novel sandwich enzyme-linked immunosorbent assay (ELISA) kits for the determination of crustacean protein in processed foods, the N kit (Nissui Pharmaceutical Co., Ltd, Ibaraki, Japan) and the M kit (Maruha Nichiro Holdings, Inc., Ibaraki, Japan), have been developed. Five types of model processed foods containing 10 and/or 11.9 g/g crustacean soluble protein were prepared for interlaboratory evaluation of the performance of these kits. The N kit displayed a relatively high level of reproducibility relative standard deviation (interlaboratory precision; 4.08.4 RSDR) and sufficient recovery (6586) for all the model processed foods. The M kit displayed sufficient reproducibility (17.620.5 RSDR) and a reasonably high level of recovery (82103). The repeatability relative standard deviation (RSDr) values regarding the detection of crustacean proteins in the 5 model foods were mostly <5.1 RSDr for the N kit and 9.9 RSDr for the M kit. In conclusion, the results of this interlaboratory evaluation suggest that both these ELISA kits would be very useful for detecting crustacean protein in processed foods.

Determination of Walnut Protein in Processed Foods by Enzyme-Linked Immunosorbent Assay: Interlaboratory Study

Because food allergens from tree nuts, including walnuts, are a frequent cause of adverse food reactions for allergic patients, the labeling of foods containing ingredients derived from tree nuts is required in numerous countries. According to Japanese regulations, the labeling of food products containing walnuts is recommended. To ensure proper labeling, a novel sandwich ELISA kit for the determination of walnut protein in processed foods (Walnut Protein [2S-Albumin] Kit; Morinaga Institute of Biological Science, Inc.; walnut kit) has been developed. We prepared seven types of incurred samples (model processed foods: biscuits, bread, sponge cake, orange juice, jelly, chicken meatballs, and rice gruel) containing 10 g walnut soluble protein/g of food for use in interlaboratory evaluations of the walnut kit. The walnut kit displayed sufficient reproducibility relative standard deviations (interlaboratory precision: 5.89.9 RSDR) and a high level of recovery (81119) for all the incurred samples. All the repeatability relative standard deviation (RSDr) values for the incurred samples that were examined were less than 6.0. The results of this interlaboratory evaluation suggested that the walnut kit could be used as a precise and reliable tool for determination of walnut protein in processed foods.

Enzyme-Linked Immunosorbent Assay Kit for the Determination of Soybean Protein in Processed Foods: Interlaboratory Evaluation

The labeling of foods containing ingredients derived from soybean is recommended in Japan because of an increasing number of patients who are allergic to soybeans. To ensure proper labeling, a novel sandwich ELISA kit for the determination of soybean protein in processed foods (FASTKIT Ver. II, Soybean, Nippon Meat Packers, Inc.; soy kit) has been developed. Five types of incurred samples (model processed foods: rice gruel, sausage, sweet adzuki bean soup, sweet potato cake, and tomato sauce) containing 10 g soybean soluble protein/g food were prepared for use in interlaboratory evaluations of the soy kit. The soy kit displayed a sufficient RSDR value (interlaboratory precision: 9.313.4 RSDR) and a high level of recovery (97114) for all the incurred samples. The RSDr value for the incurred samples was mostly <4.8. The results of this interlaboratory evaluation suggest that the soy kit can be used as a precise and reliable tool for the determination of soybean proteins in processed foods.

Intratumoural immune cell landscape in germinoma reveals multipotent lineages and exhibits prognostic significance

AIMS

Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown.

METHODS

We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases.

RESULTS

Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%).

CONCLUSIONS

The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.

Study of Immune Tolerance Cases in Adult Living Donor Liver Transplantation

BACKGROUND

Complete immune tolerance is the chief goal in organ transplantation. This study aimed to evaluate patients who successfully withdrew from immunosuppressive (IS) agents after living donor liver transplantation (LDLT).

MATERIALS AND METHODS

A retrospective review of all adult LDLT from July 1999 to March 2012 was conducted. In patients who acquired immune tolerance after LDLT, their background and the course of surgical procedures were evaluated.

RESULTS

Of a total of 101 adult LDLT patients, 8 patients were completely free of IS agents. Six of these patients (75%) were female, and the median age at the time of transplantation was 56 years (range, 31-66 years). The primary disease causing liver failure was type C liver cirrhosis (50%), fulminant hepatitis (25%), type B liver cirrhosis (12%), and alcoholic liver cirrhosis (12%). The median Child-Pugh score and MELD score were 13 points (range, 8-15 points) and 19 points (range, 10-18 points), respectively. The living related donor was the recipient's child (75%), sibling (12%), or parent (12%). ABO compatibility was identical in 62%, compatible in 25%, and incompatible in 12%.

CONCLUSIONS

In this study, we evaluated the adult patients who successfully withdrew from IS agents after LDLT. In most cases, it took more than 5 years to reduce IS agents. Because monitoring of the serum transaminase level is not adequate to detect chronic liver fibrosis in immune tolerance cases, further study is required to find appropriate protocols for reducing IS agent use after LDLT.

Successful Endoscopic Management of Acute Necrotic Pancreatitis and Walled Off Necrosis After Auxiliary Partial Orthotopic Living-Donor Liver Transplantation: A Case Report

Endoscopic management of acute necrotic pancreatitis and walled off necrosis is less invasive than surgical treatment and has become the 1st choice for treating pancreatic necrosis and abscess. We treated a case of acute necrotic pancreatitis and walled off necrosis after auxiliary partial orthotopic living-donor liver transplantation (APOLT). A 24-year-old woman was admitted to our university hospital for removal of the internal biliary stent, which had already been placed endoscopically for the treatment of biliary stricture after APOLT. She had been treated for acute liver failure by APOLT 10 years before. After we removed the internal stent with the use of an endoscopic retrograde approach, she presented with severe abdominal pain and a high fever. Her diagnosis was severe acute pancreatitis after endoscopic retrograde cholangiography (ERC). Her symptoms worsened, and she had multiple organ failure. She was transferred to the intensive care unit (ICU). Immunosuppression was discontinued because infection treatment was necessary and the native liver had already recovered sufficiently. After she had been treated for 19 days in the ICU, she recovered from her multiple organ failure. However, abdominal computerized tomography demonstrated the formation of pancreatic walled off necrosis and an abscess on the 20th day after ERC. We performed endoscopic ultrasonography-guided abscess drainage and repeated endoscopic necrosectomy. The walled off necrosis diminished gradually in size, and the symptoms disappeared. The patient was discharged on the 87th day after ERC. This is the 1st report of a case of acute necrotic pancreatitis and walled off necrosis that was successfully treated by endoscopic management after APOLT.

Six-Year Graft Survival After Partial Pancreas Heterotopic Auto-Transplantation: A Case Report

BACKGROUND

Long-term graft survival of partial pancreas auto-transplantation after total pancreatectomy has not been clarified. The clinical implications of repeat completion pancreatectomy for locally recurrent pancreatic carcinoma in the remnant pancreas after initial pancreatectomy also have not been clarified.

METHODS

We have previously reported a 61-year-old woman presenting with re-sectable carcinoma of the remnant pancreas at 3 years after undergoing a pylorus-preserving pancreaticoduodenectomy for invasive ductal carcinoma of the pancreas head. We also performed distal pancreas auto-transplantation with the use of a part of the resected pancreas to preserve endocrine function.

RESULTS

The patient was discharged at 20 days after surgery without any complications. She had been followed regularly in our outpatient clinic. She had been treated with S-1 as adjuvant chemotherapy; 72 months after the completion total pancreatectomy with distal partial pancreas auto-transplantation, the patient was alive without any evidence of the pancreatic carcinoma recurrence. The pancreas graft was still functioning with a blood glucose level of 112 mg/dL, HbA1C of 6.7%, and serum C-peptide of 1.2 ng/mL; and urinary C-peptide was 11.6 μg/d.

CONCLUSIONS

Our patient demonstrated that repeated pancreatectomies can provide a chance for survival after a locally recurrent pancreatic carcinoma if the disease is limited to the remnant pancreas. An additional partial pancreas auto-transplantation was successfully performed to preserve endocrine function. However, the indications for pancreas auto-transplantation should be decided carefully in the context of pancreatic carcinoma recurrence.

Intravenous administration of the selective toll-like receptor 7 agonist DSR-29133 leads to anti-tumor efficacy in murine solid tumor models which can be potentiated by combination with fractionated radiotherapy

Strategies to augment anti-cancer immune responses have recently demonstrated therapeutic utility. To date clinical success has been achieved through targeting co-inhibitory checkpoints such as CTLA-4, PD-1, and PD-L1. However, approaches that target co-activatory pathways are also being actively being developed. Here we report that the novel TLR7-selective agonist DSR-29133 is well tolerated in mice and leads to acute immune activation. Administration of DSR-29133 leads to the induction of IFNα/γ, IP-10, TNFα, IL-1Ra and IL-12p70, and to a reduction in tumor burden in syngeneic models of renal cancer (Renca), metastatic osteosarcoma (LM8) and colorectal cancer (CT26). Moreover, we show that the efficacy of DSR-29133 was significantly improved when administered in combination with low-dose fractionated radiotherapy (RT). Effective combination therapy required weekly administration of DSR-29133 commencing on day 1 of a fractionated RT treatment cycle, whereas no enhancement of radiation response was observed when DSR-29133 was administered at the end of the fractionated RT cycle. Combined therapy resulted in curative responses in a high proportion of mice bearing established CT26 tumors which was dependent on the activity of CD8+ T-cells but independent of CD4+ T-cells and NK/NKT cells. Moreover, long-term surviving mice originally treated with DSR-29133 and RT were protected by a tumor-specific memory immune response which could prevent tumor growth upon rechallenge. These results demonstrate that DSR-29133 is a potent selective TLR7 agonist that when administered intravenously can induce anti-tumor immune responses that can be further enhanced through combination with low-dose fractionated RT.

TLR7 tolerance is independent of the type I IFN pathway and leads to loss of anti-tumor efficacy in mice

Systemic administration of small molecule toll-like receptor (TLR)-7 agonists leads to potent activation of innate immunity and to the generation of anti-tumor immune responses. However, activation of TLRs with small molecule agonists may lead to the induction of TLR tolerance, defined as a state of hyporesponsiveness to subsequent agonism, which may limit immune activation, the generation of anti-tumor responses and clinical response. Our data reveal that dose scheduling impacts on the efficacy of systemic therapy with the selective TLR7 agonist, 6-amino-2-(butylamino)-9-((6-(2-(dimethylamino)ethoxy)pyridin-3-yl)methyl)-7,9-dihydro-8H-purin-8-one (DSR-6434). In a preclinical model of renal cell cancer, systemic administration of DSR-6434 dosed once weekly resulted in a significant anti-tumor response. However, twice weekly dosing of DSR-6434 led to the induction of TLR tolerance, and no anti-tumor response was observed. We show that TLR7 tolerance was independent of type I interferon (IFN) negative feedback because induction of TLR7 tolerance was also observed in IFN-α/β receptor knockout mice treated with DSR-6434. Moreover, our data demonstrate that treatment of bone marrow-derived plasmacytoid dendritic cells (BM-pDC) with DSR-6434 led to downregulation of TLR7 expression. From our data, dose scheduling of systemically administered TLR7 agonists can impact on anti-tumor activity through the induction of TLR tolerance. Furthermore, TLR7 expression on pDC may be a useful biomarker of TLR7 tolerance and aid in the optimization of dosing schedules involving systemically administered TLR7 agonists.

Discovery of 3H-imidazo[4,5-c]quinolin-4(5H)-ones as potent and selective dipeptidyl peptidase IV (DPP-4) inhibitors: use of a carboxylate prodrug to improve bioavailability

We have previously reported a novel series of 3H-imidazo[4,5-c]quinolin-4(5H)-ones with potent dipeptidyl peptidase IV (DPP-4) inhibitory activity. However, these compounds showed poor oral absorption. We attempted in this study esterification of the carboxylic acid moiety to improve the compounds 1-4 plasma concentrations. Our efforts yielded 10h with a 5-methyl-2-oxo-1,3-dioxol-4-yl methyl ester as an S9/plasma-cleavable functionality. Compound 10h showed significantly high oral absorption and potent DPP-4 inhibition in vivo and decreased Zucker fatty rats glucose levels in the oral glucose tolerance test. Optimization of the ester moiety revealed that rapid conversion to the carboxyl form in both liver S9 fractions and serum was important for prodrugs not to be detected in the plasma after oral administration. In particular, lability in the serum was found to be an important characteristic. Through our investigation, we were able to develop a novel efficient synthetic method for construction of 3H-imidazo[4,5-c]quinolin-4(5H)-ones using intramolecular radical cyclization.

Surgical treatment of patients with unruptured intracranial aneurysms

We present our experience with elective microsurgical clipping of unruptured intracranial aneurysms (UIA) and analyze this management. A total of 150 patients with UIA were reviewed and data were collected with regard to age, sex, presence of symptoms, location and size of the aneurysms, surgical complications and postoperative 1 year outcomes. Aneurysm size was assessed either by three-dimensional CT angiography or digital subtraction angiogram. Glasgow Outcome Scale was used to assess clinical outcomes. One hundred and fifty patients with 165 aneurysms were treated in this series. The mean size of the UIA was 5.6mm. Eighty aneurysms (48.5%) were less than 5mm in size, and 73 (44.2%) were from 5 to 10mm. Ten (6.1%) of the aneurysms were large and two (1.2%) were giant. One hundred and forty-three were asymptomatic and seven were symptomatic before surgery. The outcome was good in 147 patients (98%), and only three patients (2%) had a treatment-related unfavorable outcome. Five patients experienced transient neurological deficits and one patient experienced permanent neurological deficits. Overall 98.7% of the treated aneurysms were satisfactorily obliterated. Wound complications were seen only in three patients. In conclusion, UIA pose a significant challenge for neurosurgeons, where a delicate balance between benefits and possible risks must be weighed. If the requisite expertise is available, they can be treated surgically with low morbidity and a good outcome at specialized neurovascular centers.

Abstract 2567: Enhancement of antitumor activity of DSP-6434, a novel TLR7 agonist through reduction of TLR tolerance

Introduction: Systemic administration of the small molecule Toll-like receptor (TLR)-7 agonist DSR-6434 leads to potent activation of innate immunity and to the generation of anti-tumor immune responses. However, clinical responses with systemically administered TLR7 agonists have been underwhelming, in part because activation of TLRs with small-molecule agonists can induce TLR tolerance; defined as a state of hyporesponsiveness to subsequent agonism. This study is undertaken to identify conditions to overcome TLR tolerance.

Experimental procedures: To confirm the anti-tumor effect of DSR-6434, mice were inoculated with the mouse renal cell carcinoma cell line, Renca, at day 0, and then administrated DSR-6434 weekly from day 1, or twice weekly from day 6. To examine tolerance, wild-type or IFN-α/β receptor knockout (IFN-AR KO) mice were intravenously administrated DSR-6434 at intervals of 3, 7 or 10 days. Plasma samples were taken 2 hours after the second administration of DSR-6434 and IFN-α levels were measured. Splenocytes were isolated 24 hours following either single or sequential i.v. doses. To measure lymphocyte activation, CD69 expression was assessed and splenocyte-mediated cytotoxicity against YAC-1 target cells was determined. Bone-marrow derived pDC (BM-pDC) were also treated with DSR-6434 for 5 or 48 hours. Expression of TLR7 signaling-related genes was determined by real-time quantitative RT-PCR.

Results: Weekly administration of DSR-6434 significantly reduced tumor burden when compared to vehicle-treated mice. By contrast, pre-inoculation and 2qw administration of DSR-6434 completely abolished anti-tumor activity. IFN-α induction was completely impaired following the second administration of DSR-6434 after 3 days, partially impaired after 7 days, and fully functional when the dosing interval was extended to 10 days. Sequential dosing of DSR-6434 reduced the frequency of activated splenocytes (defined as CD69+) and the level of cytotoxicity, compared with a single administration of DSR-6434. TLR7 tolerance was also observed in IFN-AR KO mice, suggesting this effect was independent of IFN signaling. Interestingly, TLR7 down-regulation was only observed after DSR-6434 dosing, while the expression of other TLR7-signaling related genes was unaltered.

Conclusion: The dosing schedule of systemically administered TLR7 agonists significantly affect TLR tolerance and antitumor activity, offering a potential solution to overcome TLR tolerance . Furthermore, TLR7 expression on BM-pDC cells may serve as a useful biomarker of TLR7 tolerance and aid in the optimization of dosing schedules involving systemically administered TLR7 agonists.

Citation Format: Erina Koga-Yamakawa, Masashi Murata, Simon J. Dovedi, Robert W. Wilkinson, Hiroki Umehara, Eiji Sugaru, Yuko Hirose, Hideyuki Harada, David T. Robinson, Philip J. Jewsbury, Setsuko Yamamoto, Chiang J. Li. Enhancement of antitumor activity of DSP-6434, a novel TLR7 agonist through reduction of TLR tolerance. [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 2567. doi:10.1158/1538-7445.AM2014-2567

Abstract 2571: Sustained induction of TRAIL and granzyme B as well as intratumor infiltration of cytotoxic T lymphocytes (CTL) by a novel TLR7 agonist, DSR-6434, after systemic administration

Although immediate responses after treatment of TLR7 agonist have been extensively characterized the genes that are directly responsible for the antitumor activity of TLR7 agonists have not been well identified. Moreover, the immediate responses to TLR7 agonist stimulation, such as induction of interferon-alpha, IP-10 and IL-1RA, generally diminish rapidly, and therefore, cannot be used as optimal pharmacodynamic (PD) biomarkers to monitor longer term PD effects. This study was undertaken to investigate the antitumor mechanism of TLR7 agonists and to identify novel PD biomarkers. To identify PD biomarkers, mice were inoculated with mouse renal carcinoma cell line, Renca, and were administered intravenously with DSR-6434 at 0.1 mg/kg once a week, 3 times. Total RNA samples were collected 2 hours or 5 days after final dose from tumor or blood. Global gene expression profiles in tumor or blood were analyzed using GeneChip Mouse Genome 430 2.0 array (Affymetrix). Differentially expressed genes by DSR-6434 were selected compared to vehicle, and pathway analysis was performed using the genes. Expression of TRAIL and granzyme B and its time course after the administration was investigated in peripheral blood leukocytes. In tumor of mouse model, 312 and 53 genes were upregulated and downregulated, respectively, more than 2 fold at 2 hours after DSR-6434 administration. The upregulated genes included those related to immune cell activation and apoptosis pathways. The upregulated immune-related genes included T-cell marker genes (Cd3g, Cd3e), marker genes of cytotoxic T-cells (CTL) (Cd8a), lymphocyte activation (Cd69), dendritic cells activation (Cd83 and Cd86) and cytotoxic factors against tumor (TRAIL and granzyme B). These results suggested that DSR-6434 induced infiltration and activation of CTL and production of cytotoxic factors at tumor site. At 5 days after the administration of TLR7 agonist DSR-6434, 4 genes, including TRAIL, remained upregulated in tumor. Surprisingly, upregulation of TRAIL and granzyme B in blood sustained for 3 or 6 days, respectively.

In conclusion, unbiased gene expression profiling has revealed that TLR7 agonist DSR-6434 triggers CD8+ cells infiltration into tumor and sustained increase of TRAIL and granzyme B in blood for at least 3 days, thus offering novel PD biomarkers that could potentially predict antitumor activity of TLR7 agonists.

Citation Format: Ryosaku Inagaki, Mikio Aoki, Toru Kimura, Yuko Hirose, Hiroki Umehara, Erina Koga, Masashi Murata, Robert W. Wilkinson, David T. Robinson, Philip J. Jewsbury, Chiang J. Li. Sustained induction of TRAIL and granzyme B as well as intratumor infiltration of cytotoxic T lymphocytes (CTL) by a novel TLR7 agonist, DSR-6434, after systemic administration. [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 2571. doi:10.1158/1538-7445.AM2014-2571

Increased Production of Antioxidative Sesaminol Glucosides from Sesame Oil Cake through Fermentation byBacillus circulansStrain YUS-2

Bacillus circulans strain YUS-2 was isolated as the strongest antioxidant-producer in fermentation of sesame oil cake (SOC, defatted residue yielded from sesame seed oil production). Two major strong antioxidants from fermented SOC were purified and identified as known sesaminol triglucoside and sesaminol diglucoside, however, our results demonstrated that the fermentation process with B. circulans YUS-2 was highly effective to gain the extraction efficiency of the sesaminol glucosides.

Reverse-genetic approach to verify physiological roles of rice phytoalexins: characterization of a knockdown mutant of OsCPS4 phytoalexin biosynthetic gene in rice

A variety of labdane-related diterpenoids, including phytocassanes, oryzalexins and momilactones, were identified as phytoalexins in rice (Oryza sativa L.). Momilactone B was also isolated as an allelochemical exuded from rice roots. The biosynthetic genes of these phytoalexins have been identified, including six labdane-related diterpene cyclase genes such as OsCPS2, OsCPS4, OsKSL4, OsKSL7, OsKSL8 and OsKSL10. Here we identified an OsCPS4 knockdown mutant, cps4-tos, by screening Tos17 mutant lines using polymerase chain reaction. OsCPS4 encodes a syn-copalyl diphosphate synthase responsible for momilactones and oryzalexin S biosynthesis. Because Tos17 was inserted into the third intron of OsCPS4, the mature OsCPS4 mRNA was detected in the cps4-tos mutant as well as the wild type. Nevertheless, mature OsCPS4 transcript levels in the cps4-tos mutant were about one sixth those in the wild type. The cps4-tos mutant was more susceptible to rice blast fungus than the wild type, possibly due to lower levels of momilactones and oryzalexin S in the mutant. Moreover, co-cultivation experiments suggested that the allelopathic effect of cps4-tos against some kinds of lowland weeds was significantly lower than that of the wild type, probably because of lower momilactone content exuded from cps4-tos roots. A reverse-genetic strategy using the cps4-tos mutant showed the possible roles of momilactones not only as phytoalexins but also as allelopathic substances.

Skewed production of IL-6 and TGFβ by cultured salivary gland epithelial cells from patients with Sjögren's syndrome

OBJECTIVE

To determine the cytokine production profile of cultured salivary gland epithelial (SGE) cells obtained from patients with Sjögren's syndrome (SS).

METHODS

SGE cells obtained from 9 SS patients and 6 normal controls were cultured in the presence of exogenous IFNγ. Cell proliferation and apoptosis in response to IFNγ were determined by WST1 assay and by FACS analysis. The concentrations of IL-6 and TGFβ secreted into culture supernatants were analyzed by ELISA.

RESULTS

IFNγ did not significantly affect the proliferation or apoptosis of SGE cells. However, IL-6 concentrations were higher, and TGFβ concentrations were lower, in culture supernatants of SGE cells from SS patients than from normal controls.

CONCLUSION

Cytokine production by SGE cells from SS patients showed a skewed balance compared with normal controls, with increased IL-6 and decreased TGFβ secretion. This imbalance may be critical in the regulation of Treg/Th17 cells and may foster a pathogenic milieu that may be causative and predictive in SS.

Quick-scanning x-ray absorption spectroscopy system with a servo-motor-driven channel-cut monochromator with a temporal resolution of 10 ms

We have developed a quick-scanning x-ray absorption fine structure (QXAFS) system and installed it at the recently constructed synchrotron radiation beamline BL33XU at the SPring-8. Rapid acquisition of high-quality QXAFS data was realized by combining a servo-motor-driven Si channel-cut monochromator with a tapered undulator. Two tandemly aligned monochromators with channel-cut Si(111) and Si(220) crystals covered energy ranges of 4.0-28.2 keV and 6.6-46.0 keV, respectively. The system allows the users to adjust instantly the energy ranges of scans, the starting angles of oscillations, and the frequencies. The channel-cut crystals are cooled with liquid nitrogen to enable them to withstand the high heat load from the undulator radiation. Deformation of the reflecting planes is reduced by clamping each crystal with two cooling blocks. Performance tests at the Cu K-edge demonstrated sufficiently high data quality for x-ray absorption near-edge structure and extended x-ray absorption fine-structure analyses with temporal resolutions of up to 10 and 25 ms, respectively.

Intraoperative near-infrared indocyanine green-videoangiography (ICG-VA) and graphic analysis of fluorescence intensity in cerebral aneurysm surgery

We present our preliminary experience with intraoperative near-infrared indocyanine green-videoangiography (ICG-VA) and analysis of blood flow dynamics using fluorescence intensity assessment in cerebral aneurysm clipping surgery. Thirty-nine patients with 43 intracranial aneurysms underwent microsurgical clipping. Intraoperative ICG-VA was performed before and after clip application. An infrared fluorescence module integrated into a surgical microscope was used to visualize fluorescence in the surgical field and we recorded the emitted fluorescent light. An integrated analytical visualization tool simultaneously analyzed the video sequence and converted it into an intensity diagram, which allowed an objective evaluation of the results rather than the subjective assessment of fluorescence using ICG-VA. Overall, ICG-VA was performed 137 times. Incomplete clipping was detected in four patients, which allowed suitable adjustment to completely obliterate the aneurysm. In 12 patients, perforators arising close to, or from, the aneurysmal neck were identified in the surgical field. In three patients, the ICG-VA intensity diagram provided valuable information leading to modification of the primary surgical maneuver. ICG-VA provides high resolution images allowing real-time assessment of the blood flow in the parent artery and arterial branches, including the perforators. The intensity diagram is useful for providing a more objective record of the hemodynamics than the traditional ICG-VA, which relies more on subjective assessment and may allow interobserver variability. We conclude that ICG-VA, combined with the intensity diagram, can reduce the morbidity and complications associated with aneurysm clipping and improve patient outcomes.

Comparison of cerebral aneurysm volumes as determined by digitally measured 3D rotational angiography and approximation from three diameters

This study compared digital measurement of aneurysm volume by 3D rotational angiography (3D-RA) with an approximation technique using three diameters of an aneurysm to re-interpret previously reported optimal packing densities (volume embolization ratio, VER) in coil embolization of intracranial aneurysms. Estimation of the volume of saccular aneurysms is important for calculation of the VER, which is in turn reported to be useful for prediction of coil compaction. The conventional formula for the volume estimation is V=4/3 π(A/2) (B/2) (C/2), where A, B, and C are the aneurysmal height, length, and width measured on 3D-RA image respectively. Using 3D rotational angiography data from 74 aneurysms, the approximated volume generated using the conventional formula was directly compared with the digitally measured volume. The digitally measured volume varied from 0.003 ml to 7.935 ml, and the dome-to-neck ratio (D/N) from 0.79 up to 4.62. We found that the conventional formula almost systematically underestimated the volume by up to 50 %, particularly when the neck was large relative to the dome (D/N<2). On average, digitally measured volume was 1.26~1.29 times larger than the approximated volume obtained using the conventional formula.Conventional 2D angiography based aneurysm volume calculation tends to underestimate an aneurysm volume, so the so-called VER (volume embolization ratio) could be overestimated.

High-dose methotrexate with R-CHOP therapy for the treatment of patients with primary central nervous system lymphoma

We describe MR-CHOP therapy, a novel treatment regimen consisting of high-dose methotrexate and R-CHOP that provides systemic anti-tumor activity with penetration of the blood-brain barrier in patients with newly diagnosed primary central nervous system lymphoma. The MR-CHOP regimen was administered with 2 g/m(2) of methotrexate and 375 mg/m(2) of rituximab on day 1, 750 mg/m(2) of cyclophosphamide on day 3, 50 mg/m(2) of doxorubicin on day 3, 1.4 mg/m(2) of vincristine on day 3 and 100 mg of prednisolone on days 1-5 in this pilot study of seven patients. Six cycles of MR-CHOP therapy were administered every 3 weeks, followed by high-dose chemotherapy with stem cell rescue in young patients, or an additional two cycles of 4 g/m(2) methotrexate and rituximab in older patients. The overall response rate was 100%, with 85.7% complete remission (CR). One patient showed partial response, relapsed and subsequently died. Another relapsed following CR, and was rescued by further salvage therapy. The others survive without relapse at a median observation period of 24 months. Hematological toxicity included grade 4 leukocytopenia in 4/7 and neutropenia in 5/7, which were transient and tolerated well. Non-hematological toxicities were tolerated well. The efficacy of this novel regimen as remission induction therapy was found to be promising in this pilot study, although the number of patients was small and follow-up short.