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.

Phase 1/2, open-label, dose-escalation, dose-expansion study of menin inhibitor DSP-5336 in adult patients with acute leukemia with and without mixed-lineage leukemia (MLL)-rearrangement (r) or nucleophosmin 1 (NPM1) mutation (m)

TPS7066

Background: DSP-5336, a menin MLL interaction inhibitor, elicited antitumor activity in MLL–r or NPM1m acute leukemia models in vitro and in vivo. An open-label, single-arm, phase 1/2 study (NCT04988555) will evaluate the safety and efficacy of DSP-5336 and determine the recommended phase 2 dose (RP2D) in patients with relapsed/refractory (R/R) acute myeloid leukemia (AML) or acute lymphocytic leukemia (ALL). Methods: Patients aged ≥18 y with R/R AML, ALL, or acute leukemia of ambiguous lineage after ≥1 line of standard therapy, ECOG PS 0–2, and adequate organ function are eligible. Patients will receive DSP-5336 twice daily for 28 d/cycle. In phase 1, there will be two parallel escalation cohorts: patients who do not receive concomitant azole antifungal medication and patients who receive antifungal azoles (ie, posaconazole, voriconazole, or fluconazole); 21–30 patients will be enrolled during phase 1 into multiple ascending dose levels. Dose escalation will use a Bayesian logistic regression model. Phase 2 will enroll two arms: R/R AML with MLL –r and R/R AML with NPM1m (10 –20 patients/arm). Patients will be treated at the RP2D to evaluate clinical activity and safety. Clinical trial information: NCT04988555. [Table: see text]

Randomised phase II trial of irinotecan plus S-1 in patients with gemcitabine-refractory pancreatic cancer

Background:

We aimed to compare the efficacy and safety of irinotecan/S-1 (IRIS) therapy with S-1 monotherapy in patients with gemcitabine-refractory pancreatic cancer.

Methods:

Patients were treated with oral S-1 (80–120 mg for 14 days every 4 weeks) plus intravenous irinotecan (100 mg m⁻² on days 1 and 15 every 4 weeks; IRIS group) or oral S-1 group (80–120 mg daily for 28 days every 6 weeks). The primary endpoint was progression-free survival (PFS).

Results:

Of 137 patients enrolled, 127 were eligible for efficacy. The median PFS in the IRIS group and S-1 monotherapy group were 3.5 and 1.9 months, respectively (hazard ratio (HR)=0.77; 95% confidence interval (CI), 0.53–1.11; P=0.18), while the median overall survival (OS) were 6.8 and 5.8 months, respectively (HR=0.75; 95% CI, 0.51–1.09; P=0.13). Response rate was significantly higher in the IRIS group than in the S-1 monotherapy group (18.3% vs 6.0%, P=0.03). Grade 3 or higher neutropenia and anorexia occurred more frequently in the IRIS group.

Conclusions:

There was a trend for better PFS and OS in the IRIS group that could be a treatment arm in the clinical trials for gemcitabine-refractory pancreatic cancer.

Computed Tomography of Anterior Mediastinal Tumors

Computed tomographic (CT) features in 10 patients with germ cell tumor of the mediastinum and 15 with thymoma were compared with surgically resected specimens. The CT findings of the internal structure of tumors were the most important factor for specific diagnosis. Germ cell tumors showed a round mass without distinct lobulation, frequently with calcification appearing as a globular shape, and especially in benign tumors as an arched shape along the wall. Homogeneous low density masses (near-water) with a thick wall were benign and non-homogeneous density masses (a mixture of near-water and soft tissue) were malignant. Thymoma usually showed a solid mass with lobulation and sometimes had an eggshell type of calcification in the tumor. Therefore, CT is of importance in the diagnosis of anterior mediastinal masses.

Emergence of Epstein-Barr virus-associated haemophagocytic syndrome upon treatment of systemic lupus erythematosus

A 32-year-old female patient with systemic lupus erythematosus was admitted to our hospital with fever and cytopenia, and diagnosed as haemophagocytic syndrome (HPS) by bone marrow aspiration study showing haemophagocytosis. Since the serologic activity of lupus was not increased at that time and HPS was refractory to the conventional therapies, an additional aetiological factor was suspected. Real-time PCR analysis identified reactivation of Epstein-Barr virus (EBV). A combination therapy targetting EBV-associated HPS, consisting of intravenous administration of cyclosporine A as well as immunoglobulin with a high titre of anti-EBV antibody, significantly suppressed EBV viraemia and led to the remission of HPS until the time of writing.

In vitro investigation of molecules involved in Lactobacillus gasseri SBT2055 adhesion to host intestinal tract components

AIMS

The adhesion ability of Lactobacillus gasseri SBT2055 was investigated in vitro by searching for its adhesion molecules.

METHODS AND RESULTS

Lactobacillus gasseri SBT2055 showed adherence to host components, including two commercially available mucins, Caco-2 epithelial-like cells and the extracellular matrix molecule fibronectin (Fn). Its adhesion rates to host components were generally higher than those of other Lactobacillus strains. We examined sortase-dependent proteins (SDPs) anchored by a sortase enzyme encoded by srtA1. The adhesion rates of an srtA1 disruptant were lower than those of Lact. gasseri SBT2055, and the relative adherences were as follows: two mucins, 43 and 40%; Caco-2, 66% and Fn, 28%. Seven additional gene disruptants were generated to determine the precise SDPs that contribute to adhesion to each component.

CONCLUSIONS

The adhesion ability of Lact. gasseri SBT2055 was superior to those of other Lactobacillus strains. Additionally, four adhesion molecules were newly identified from candidate SDPs.

SIGNIFICANCE AND IMPACT OF THE STUDY

Although the contribution of SDPs to adhesion has been reported using sortase gene disruptants, this is the first report to identify the precise SDPs that act as adhesion molecules. Our results will contribute to achieving better understanding of probiotic bacterial adherence.

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.

Increased prevalence of MEFV exon 10 variants in Japanese patients with adult-onset Still's disease

Autoinflammatory diseases include a large spectrum of monogenic diseases, e.g. familial Mediterranean fever (FMF), as well as complex genetic trait diseases, e.g. adult-onset Still's disease (AOSD). In populations where FMF is common, an increased MEFV mutation rate is found in patients with rheumatic diseases. The aim of this study was to examine MEFV mutations in Japanese patients with AOSD. Genomic DNA was isolated from 49 AOSD patients and 105 healthy controls, and exons 1, 2, 3 and 10 of the MEFV gene genotyped by direct sequencing. MEFV mutation frequencies in AOSD patients were compared with controls. We found no significant difference in overall allele frequencies of MEFV variants between AOSD patients and controls. However, MEFV exon 10 variants (M694I and G632S) were significantly higher in AOSD patients than controls (6.1 versus 0%). In addition, there was no significant difference between MEFV variant carriers and non-carriers with clinical manifestations, but the monocyclic clinical course of the AOSD disease phenotype was observed less frequently in patients without MEFV variants. AOSD patients had significantly higher frequencies of MEFV exon 10 mutations, suggesting that low-frequency variants of MEFV gene may be one of the susceptibility factors of AOSD.

SUBCUTANEOUS FAT NECROSIS ASSOCIATED WITH PANCREATITIS AND GASTRIC CARCINOMA

Subcutaneous fat necrosis associated with acute pancreatitis in a 54-year-old man was reported. The acute pancreatitis was proved histologically after gastrectomy for coincident early gastric carcinoma. The patient was successfully treated with prednisolone and his skin lesions subsided within a month.

Effects of treadmill exercise on muscle fibers in mice with steroid myopathy

We studied the effect of treadmill exercise on muscle fibers in mice with experimental steroid myopathy. Frozen sections of the extensor digitorum longus (EDL) and soleus (SOL) muscles were stained with hematoxylin-eosin, and the muscle fiber diameters measured. In the EDL, muscle fiber diameters in the steroid groups decreased significantly compared with those in the control groups; moreover, muscle fiber diameters in the exercise groups increased significantly compared with those in the non-exercise groups, whereas the diameters in the SOL did not differ. We speculate that treadmill exercise may prevent corticosteroid-induced muscle fiber atrophy.

Effects of short duration stretching on disuse muscle atrophy in immobilized rat soleus muscles

The purpose of this study was to determine whether short duration stretching is ameliorating for disuse muscle atrophy in immobilized rat soleus muscles. Eighteen male Wistar rats (age, 8 weeks; weight, 311.0 ± 35.6 g) were divided randomly into control (n=3) and experimental (n=15) groups. Bilateral ankles of each rat in the experimental group were fixed in full planter flexion with a plaster cast. After the experimental groups rats were immobilized for 4 weeks, animals were divided into three groups: immobilization alone (group I, n=3), stretch training for 30 min/day for 1 or 3 weeks after remobilization (group S, n=6), and spontaneous recovery (non stretch training) for 1 or 3 weeks after remobilization (group NS, n=6). At the end of the experimental periods, the soleus muscle was extracted from hindlimb, and the frozen sections were stained with myofibrillar adenosine triphosphatase. After 1 week of remobilization, the means of the muscle fiber diameters for type I fibers in group S had increased significantly compared with group NS, but those for type II fibers in group S did not significantly differ from that for group NS. After 3 weeks of remobilization, the means of the muscle fiber diameters for types I and II fibers in group S had increased significantly compared with group NS. No difference in the fiber type distribution were observed between the experimental group. Our findings suggest that short duration stretching induces recovery from disuse muscle atrophy after joint fixation.

Phase II trial of combination therapy of gemcitabine plus anti-angiogenic vaccination of elpamotide in patients with advanced or recurrent biliary tract cancer

Background Elpamotide is an HLA-A*24:02-restricted epitope peptide of vascular endothelial growth factor receptor 2 (VEGFR-2) and induces cytotoxic T lymphocytes (CTLs) against VEGFR-2/KDR. Given the high expression of VEGFR-2 in biliary tract cancer, combination chemoimmunotherapy with elpamotide and gemcitabine holds promise as a new therapy. Patients and Methods Patients with unresectable advanced or recurrent biliary tract cancer were included in this single-arm phase II trial, with the primary endpoint of overall survival. Survival analysis was performed in comparison with historical control data. The patients concurrently received gemcitabine once a week for 3 weeks (the fourth week was skipped) and elpamotide once a week for 4 weeks. Results Fifty-five patients were registered, of which 54 received the regimen and were included in the full analysis set as well as the safety analysis set. Median survival was 10.1 months, which was longer than the historical control, and the 1-year survival rate was 44.4 %. Of these patients, injection site reactions were observed in 64.8 %, in whom median survival was significantly longer (14.8 months) compared to those with no injection site reactions (5.7 months). The response rate was 18.5 %, and all who responded exhibited injection site reactions. Serious adverse reactions were observed in five patients (9 %), and there were no treatment-related deaths. Conclusion Gemcitabine and elpamotide combination therapy was tolerable and had a moderate antitumor effect. For future development of therapies, it will be necessary to optimize the target population for which therapeutic effects could be expected.

Abstract 2217: Genomic alteration of bromodomain protein ATAD2 in cancer

ATPase family, AAA domain containing 2 (ATAD2), is a member of the bromodomain-containing protein family. ATAD2 associates with co-factors such as hormone receptors, E2Fs and c-Myc to control a specific subset of genes. Overexpression and copy number alteration of ATAD2 are observed in many types of cancer, and these alterations are correlated with poor clinical outcome in breast, lung, and endometrial cancers. Here, we present an integrated genomic analysis of ATAD2 using the Oncomine™ database that shows cancer-associated features of ATAD2. In The Cancer Genome Atlas, amplifications of ATAD2 are observed in 63% of ovarian, 52% of breast, 39% of colorectal, and 18% of lung cancer patients. By contrast, no amplification of ATAD2 is observed in corresponding normal tissues. In most cases, amplifications are modest ranging up to a copy number of six. Moreover, a high correlation between ATAD2 mRNA expression levels and its copy number is observed in cultured cell lines. In order to investigate the role of the bromodomain in ATAD2, we conducted a cell-free physicochemical binding analysis and in vitro physiological studies using human colon cancer cells (HCT-116). To identify binding partners for the ATAD2 bromodomain, we constructed ATAD2 AlphaScreen systems and examined the binding activity of the ATAD2 bromodomain protein to various acetylated or non-acetylated histone peptides. The ATAD2 bromodomain interacted with histone H4 acetylated at lysine 5, 8 or 12, but not with other acetylated and non-acetylated histone peptides. Subcellular localization analysis by immunofluorescence, demonstrated that ATAD2 is mainly localizes to nucleus and that treatment with trichostatin A, an inhibitor of histone deacetylases increased nuclear ATAD2 protein levels, suggesting that the acetylation level of histone tails may affect ATAD2 expression or localization. In in silico expression analysis using the Cancer Cell Line Encyclopedia, showed most genes that correlated with ATAD2 expression have a role in proliferation or survival. To determine if the ATAD2 protein directly controls transcription of these genes, we performed ChIP-PCR assays and found that ATAD2 protein occupies the DNA promoter regions of downstream targets, eg. TOP2A, but does not occupy the promoters of non-target negative controls, such as β-actin. In conclusion, we show ATAD2 copy number alteration in a large number of cancer patients, suggesting that ATAD2 expression, or genomic alteration, may be useful prognostic markers of cancer. We also show that physicochemical binding of the ATAD2 bromodomain to specific acetylated histone peptides suggesting a physiological function of ATAD2 in nucleus as a transcriptional regulator of tumor-related genes. These results suggest that a blockade of ATAD2 bromodomain binding to specific acetylated histone tails may provide a novel approach to anti-tumor drug development.

Citation Format: Tomoyo Takeda, Yuta Matsumura, Hirotoshi Nagasaki, Ken Eguchi, Miki Takatsuka, Yoichi Shinkai, Hiroyuki Nakagawa, Hitoshi Kawashima, Hiroyuki Ueno, Chiang J. Li. Genomic alteration of bromodomain protein ATAD2 in cancer. [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 2217. doi:10.1158/1538-7445.AM2014-2217

Blood Pressure Variability/Dipper/Non-dipper in Hypertension and Diabetes

It has been well recognized that hypertension in diabetes is a potent risk of micro- and macrovascular complications. BP levels are most important component of BP management. Next to BP levels, other component such as BP variability is also important. BP variability consists of several concepts [1]

1) Very Short term BP variability (beat-to-beat)

2) Short term BP variability (over the 24h)

3) Diurnal BP variation in diabetes

4) Long term BP variability (day-by-day)

5) Visit-to-Visit Variability (months ~ years)

Among these, abnormal circadian rhythm of BP belongs to short-term BP variability. There have been a number of papers about BP variability in recent years. In this chapter, the significance of BP variability in patients with diabetes will be reviewed.

MEFV gene polymorphisms and TNFRSF1A mutation in patients with inflammatory myopathy with abundant macrophages

Inflammatory myopathy with abundant macrophages (IMAM) has recently been proposed as a new clinical condition. Although IMAM shares certain similarities with other inflammatory myopathies, the mechanisms responsible for this condition remain unknown. Patients with familial Mediterranean fever (FMF) and tumour necrosis factor receptor-associated periodic syndrome (TRAPS) also often develop myalgia. We therefore investigated the polymorphisms or mutations of MEFV and TNFRSF1A genes in patients with IMAM to identify their potential role in this condition. We analysed the clinical features of nine patients with IMAM and sequenced exons of the MEFV and TNFRSF1A genes. The patients with IMAM had clinical symptoms such as myalgia, muscle weakness, erythema, fever and arthralgia. Although none of the patients were diagnosed with FMF or TRAPS, seven demonstrated MEFV polymorphisms (G304R, R202R, E148Q, E148Q-L110P and P369S-R408Q), and one demonstrated a TNFRSF1A mutation (C43R). These results suggest that MEFV gene polymorphisms and TNFRSF1A mutation are susceptibility and modifier genes in IMAM.

Inhibition of Janus kinase/signal transducer and activator of transcription (JAK/STAT) signalling pathway in rheumatoid synovial fibroblasts using small molecule compounds

Janus kinase (JAK) inhibitors have been developed as anti-inflammatory agents and have demonstrated clinical efficacy in rheumatoid arthritis (RA). We investigated if JAK-3-selective inhibition alone could disrupt cytokine signalling in rheumatoid synovial fibroblasts. In-vitro studies were performed using synovial fibroblasts isolated from patients with RA. Levels of activated JAK and signal transducer and activator of transcription (STAT) proteins were detected by immunoblot analysis. Target-gene expression levels were measured by reverse transcription-polymerase chain reaction (RT-PCR) or real-time PCR. The JAK inhibitors CP-690,550 and INCB028050 both suppressed activation of JAK-1/-2/-3 and downstream STAT-1/-3/-5, as well as the expression levels of target proinflammatory genes (MCP-I, SAA1/2) in oncostatin-M (OSM)-stimulated rheumatoid synovial fibroblasts. In contrast, the JAK-3-selective inhibitor, PF-956980, suppressed STAT-1/-5 activation but did not affect STAT-3 activation in OSM-stimulated rheumatoid synovial fibroblasts. In addition, PF-956980 significantly suppressed MCP-1 gene expression, but did not block SAA1/2 gene expression in OSM-stimulated rheumatoid synovial fibroblasts. These data suggest that JAK-3-selective inhibition alone is insufficient to control STAT-3-dependent signalling in rheumatoid synovial fibroblasts, and inhibition of JAKs, including JAK-1/-2, is needed to control the proinflammatory cascade in RA.

Atypical mycobacteriosis in two patients with rheumatoid arthritis

Abstract We report two cases of rheumatoid arthritis (RA) with atypical mycobacteriosis. Opportunistic infections are critical complications for rheumatic diseases. The use of steroids or immunosuppressants may increase the risk of opportunistic infections. However, these reports are rare in that they demonstrate atypical mycobacterial infections as complications of RA, even though no immunosuppressive agents were used. We discuss the characteristics of atypical mycobacterial infections of the lung in RA.