Different types of reactions to E7386 among colorectal cancer patient-derived organoids and corresponding CAFs.

Colorectal cancer (CRC) harbors genetic alterations in a component of the Wnt signaling pathway in ~90% of cases. In addition, the Wnt signaling pathway has been previously suggested to serve a notable role in the pathophysiology of CRC cells and cancer-associated fibroblasts (CAFs). In the present study, the possible effects of E7386, a selective inhibitor of the interaction between ß-catenin and the cAMP response element-binding protein-binding protein, were evaluated using organoids and the corresponding CAFs derived from patients with CRC. E7386 at 100 nM was revealed to decrease the viability of CRC organoids and CAFs. Analysis of the gene expression profiles revealed marked changes in the expression levels of different types of cancer-associated genes associated with E7386 concentrations in the organoids and/or CAFs, such as those regulating glucose and amino acid metabolism [phosphoenolpyruvate carboxykinase 2, asparagine synthetase (glutamine-hydrolyzing), phosphoserine aminotransferase 1 and phosphoglycerate dehydrogenase], stimulation of natural killer cell-mediated cytotoxicity (UL16-binding protein 1) and modification of the Wnt/ß-catenin signaling pathway (indicated by very low density lipoprotein receptor). Results of the hydrophilic metabolome analysis in the organoids were consistent with those of the transcriptomic analysis. In vivo experiments used corresponding xenograft models, although changes in volume of tumor tissues could not be observed at 50 mg/kg body weight twice a day for 14 days, results on the protein expression levels partially supported those in the in vitro experiments. In conclusion, different types of reactions, such as alterations in the glucose and amino acid metabolic pathways, stimulation of stress responses and NK-cell mediated cytotoxicity and components in the Wnt/ß-catenin signaling pathway, to E7386 in the CRC organoids and corresponding CAFs were observed under conditions with decreased cell viability. However, further mechanistic studies to clarify the relationships with Wnt/ß-catenin signaling pathway and these reactions using preclinical models and biomarker studies using clinical human samples are required for verification of the present preclinical biomarkers.

New Cluster Analysis Method for Quantitative Dynamic Contrast-Enhanced MRI Assessing Tumor Heterogeneity Induced by a Tumor-Microenvironmental Ameliorator (E7130) Treatment to a Breast Cancer Mouse Model.

BACKGROUND: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can provide insight into tumor perfusion. However, a method that can quantitatively measure the intra-tumor distribution of tumor voxel clusters with a distinct range of Ktrans and ve values remains insufficiently explored. HYPOTHESIS: Two-dimensional cluster analysis may quantify the distribution of a tumor voxel subregion with a distinct range of Ktrans and ve values in human breast cancer xenografts. STUDY TYPE: Prospective longitudinal study. ANIMAL MODEL: Twenty-two female athymic nude mice with MCF-7 xenograft, treated with E7130, a tumor-microenvironmental ameliorator, or saline. FIELD STRENGTH/SEQUENCE: 9.4 Tesla, turbo rapid acquisition with relaxation enhancement, and spoiled gradient-echo sequences. ASSESSMENT: We performed two-dimensional k-means clustering to identify tumor voxel clusters with a distinct range of Ktrans and ve values on Days 0, 2, and 5 after treatment, calculated the ratio of the number of tumor voxels in each cluster to the total number of tumor voxels, and measured the normalized distances defined as the ratio of the distance between each tumor voxel and the nearest tumor margin to a tumor radius. STATISTICAL TESTS: Unpaired t-tests, Dunnett's multiple comparison tests, and Chi-squared test were used. RESULTS: The largest and second largest clusters constituted 44.4% and 27.5% of all tumor voxels with cluster centroid values of Ktrans at 0.040 min-1 and 0.116 min-1 , and ve at 0.131 and 0.201, respectively. At baseline (Day 0), the average normalized distances for the largest and second largest clusters were 0.33 and 0.24, respectively. E7130-treated group showed the normalized distance of the initial largest cluster decreasing to 0.25, while that of the second largest cluster increasing to 0.31. Saline-treated group showed no change. DATA CONCLUSION: A two-dimensional cluster analysis might quantify the spatial distribution of a tumor subregion with a distinct range of Ktrans and ve values. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 1.

E7386, a Selective Inhibitor of the Interaction between ß-Catenin and CBP, Exerts Antitumor Activity in Tumor Models with Activated Canonical Wnt Signaling.

The Wnt/ß-catenin signaling pathway plays crucial roles in embryonic development and the development of multiple types of cancer, and its aberrant activation provides cancer cells with escape mechanisms from immune checkpoint inhibitors. E7386, an orally active selective inhibitor of the interaction between ß-catenin and CREB binding protein, which is part of the Wnt/ß-catenin signaling pathway, disrupts the Wnt/ß-catenin signaling pathway in HEK293 and adenomatous polyposis coli (APC)-mutated human gastric cancer ECC10 cells. It also inhibited tumor growth in an ECC10 xenograft model and suppressed polyp formation in the intestinal tract of ApcMin /+ mice, in which mutation of Apc activates the Wnt/ß-catenin signaling pathway. E7386 demonstrated antitumor activity against mouse mammary tumors developed in mouse mammary tumor virus (MMTV)-Wnt1 transgenic mice. Gene expression profiling using RNA sequencing data of MMTV-Wnt1 tumor tissue from mice treated with E7386 showed that E7386 downregulated genes in the hypoxia signaling pathway and immune responses related to the CCL2, and IHC analysis showed that E7386 induced infiltration of CD8+ cells into tumor tissues. Furthermore, E7386 showed synergistic antitumor activity against MMTV-Wnt1 tumor in combination with anti-PD-1 antibody. In conclusion, E7386 demonstrates clear antitumor activity via modulation of the Wnt/ß-catenin signaling pathway and alteration of the tumor and immune microenvironments, and its antitumor activity can be enhanced in combination with anti-PD-1 antibody. SIGNIFICANCE: These findings demonstrate that the novel anticancer agent, E7386, modulates Wnt/ß-catenin signaling, altering the tumor immune microenvironment and exhibiting synergistic antitumor activity in combination with anti-PD-1 antibody.

Lenvatinib plus anti-PD-1 antibody combination treatment activates CD8+ T cells through reduction of tumor-associated macrophage and activation of the interferon pathway.

Lenvatinib is a multiple receptor tyrosine kinase inhibitor targeting mainly vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) receptors. We investigated the immunomodulatory activities of lenvatinib in the tumor microenvironment and its mechanisms of enhanced antitumor activity when combined with a programmed cell death-1 (PD-1) blockade. Antitumor activity was examined in immunodeficient and immunocompetent mouse tumor models. Single-cell analysis, flow cytometric analysis, and immunohistochemistry were used to analyze immune cell populations and their activation. Gene co-expression network analysis and pathway analysis using RNA sequencing data were used to identify lenvatinib-driven combined activity with anti-PD-1 antibody (anti-PD-1). Lenvatinib showed potent antitumor activity in the immunocompetent tumor microenvironment compared with the immunodeficient tumor microenvironment. Antitumor activity of lenvatinib plus anti-PD-1 was greater than that of either single treatment. Flow cytometric analysis revealed that lenvatinib reduced tumor-associated macrophages (TAMs) and increased the percentage of activated CD8+ T cells secreting interferon (IFN)-γ+ and granzyme B (GzmB). Combination treatment further increased the percentage of T cells, especially CD8+ T cells, among CD45+ cells and increased IFN-γ+ and GzmB+ CD8+ T cells. Transcriptome analyses of tumors resected from treated mice showed that genes specifically regulated by the combination were significantly enriched for type-I IFN signaling. Pretreatment with lenvatinib followed by anti-PD-1 treatment induced significant antitumor activity compared with anti-PD-1 treatment alone. Our findings show that lenvatinib modulates cancer immunity in the tumor microenvironment by reducing TAMs and, when combined with PD-1 blockade, shows enhanced antitumor activity via the IFN signaling pathway. These findings provide a scientific rationale for combination therapy of lenvatinib with PD-1 blockade to improve cancer immunotherapy.

Synthesis of 2-Aryloxy-1,3-dienes from Phenols and Propargyl Carbonates.

A convenient method for the synthesis of 1,3-dienes from readily available compounds is reported. 2-Aryoxy-1,3-dienes are produced stereoselectively by a nickel-catalyzed reaction of propargyl carbonates with phenols. Functional group tolerance is broad to allow iodo, formyl, and boryl groups. The resulting 1,3-dienes are of much synthetic value because they can participate in a wide variety of reactions, including the Diels-Alder reaction.

Immunomodulatory activity of lenvatinib contributes to antitumor activity in the Hepa1-6 hepatocellular carcinoma model.

Angiogenesis inhibitors such as lenvatinib and sorafenib, and an immune checkpoint inhibitor (ICI), nivolumab, are used for anticancer therapies against advanced hepatocellular carcinoma (HCC). Combination treatments comprising angiogenesis inhibitors plus ICIs are promising options for improving clinical benefits in HCC patients, and clinical trials are ongoing. Here, we investigated the antitumor and immunomodulatory activities of lenvatinib (a multiple receptor tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor 1-3, fibroblast growth factor receptor 1-4, platelet-derived growth factor receptor α, KIT and RET) and the combined antitumor activity of lenvatinib plus anti-programmed cell death 1 (PD-1) antibody in the Hepa1-6 mouse HCC syngeneic model. We found that the antitumor activities of lenvatinib and sorafenib were not different in immunodeficient mice, but lenvatinib showed more potent antitumor activity than sorafenib in immunocompetent mice. The antitumor activity of lenvatinib was greater in immunocompetent mice than in immunodeficient mice and was attenuated by CD8+ T cell depletion. Treatment with lenvatinib plus anti-PD-1 antibody resulted in more tumor regression and a higher response rate compared with either treatment alone in immunocompetent mice. Single-cell RNA sequencing analysis demonstrated that treatment with lenvatinib with or without anti-PD-1 antibody decreased the proportion of monocytes and macrophages population and increased that of CD8+ T cell populations. These data suggest that lenvatinib has immunomodulatory activity that contributes to the antitumor activity of lenvatinib and enhances the antitumor activity in combination treatment with anti-PD-1 antibody. Combination treatment of lenvatinib plus anti-PD-1 antibody therefore warrants further investigation against advanced HCC.

Functional Characterization of VEGF- and FGF-induced Tumor Blood Vessel Models in Human Cancer Xenografts.

BACKGROUND/AIM: Tumor angiogenesis induced by vascular endothelial growth factor (VEGF) and/or fibroblast growth factor (FGF) plays an important role in tumor growth, metastasis, and drug resistance. However, the characteristics of tumor vessels derived from these angiogenic factors have not been fully explored. MATERIALS AND METHODS: To functionally examine tumor vessels, we developed in vivo VEGF- and FGF-induced tumor blood vessel models. We performed immunohistochemistry and Hoechst perfusion assay to elucidate histopathological differences between the derived tumor vessels. To kinetically understand tumor perfusion, we employed radiolabeled PEGylated liposomes. RESULTS: While tumor vessel density was substantially increased by enhanced expression levels of VEGF and FGF, permeability of VEGF-driven tumor vessels was significantly higher than that of FGF-driven ones, the latter demonstrating an increased number of pericyte-covered vessels. Accordingly, we observed an increased tumor retention of the PEGylated liposomes in the VEGF-driven tumor. CONCLUSION: Our in vivo models of tumor vessel demonstrate the frequency of pericyte coverage and tumor perfusion levels as major functional differences between VEGF- and FGF-driven tumor vessels.

Radiolabeled liposome imaging determines an indication for liposomal anticancer agent in ovarian cancer mouse xenograft models.

Liposomal anticancer agents can effectively deliver drugs to tumor lesions, but their therapeutic effects are enhanced in only limited number of patients. Appropriate biomarkers to identify responder patients to these liposomal agents will improve their treatment efficacies. We carried out pharmacological and histopathological analyses of mouse xenograft models bearing human ovarian cancers (Caov-3, SK-OV-3, KURAMOCHI, and TOV-112D) to correlate the therapeutic effects of doxorubicin-encapsulated liposome (Doxil(®) ) and histological characteristics linked to the enhanced permeability and retention effect. We next generated (111) In-encapsulated liposomes to examine their capacities to determine indications for Doxil(®) treatment by single-photon emission computed tomography (SPECT)/CT imaging. Antitumor activities of Doxil(®) were drastically enhanced in Caov-3, moderately in SK-OV-3, and minimally in KURAMOCHI and TOV-112D when compared to doxorubicin. Microvessel density and vascular perfusion were high in Caov-3 and SK-OV-3, indicating a close relation with the enhanced antitumor effects. Next, (111) In-encapsulated liposomes were given i.v. to the animals. Their tumor accumulation and area under the curve values over 72 h were high in Caov-3, relatively high in SK-OV-3, and low in two other tumors. Importantly, as both Doxil(®) effects and liposomal accumulation varied in the SK-OV-3 group, we individually obtained SPECT/CT images of SK-OV-3-bearing mouse (n = 11) before Doxil(®) treatment. Clear correlation between liposomal tumor accumulation and effects of Doxil(®) was confirmed (R(2) = 0.73). Taken together, our experiments definitely verified that enhanced therapeutic effects through liposomal formulations of anticancer agents depend on tumor accumulation of liposomes. Tumor accumulation of the radiolabeled liposomes evaluated by SPECT/CT imaging is applicable to appropriately determine indications for liposomal antitumor agents.

Promotion of mouse two-stage skin carcinogenesis by diacylglycerol-rich edible oil.

Tumor promotion potential of diacylglycerol (DAG)-rich edible oil was examined using a two-stage mouse skin carcinogenesis model initiated with 7,12-dimethylbenz[a]anthracene (DMBA). Topical treatment with 75 mg DAG oil once a day for 5 days/week for 35 weeks caused papillomas in 4 of 23 (17%) DMBA-treated female ICR mice, while DMBA initiation alone and DAG treatment without DMBA initiation did not induce any skin tumors. Doubling the daily treatment (twice a day x 5 days/week) at doses of 75 and 30 mg caused both papillomas and squamous cell carcinomas after DMBA initiation, the incidences of tumors being 48% (12/25) and 44% (11/25), respectively, significantly higher than the 4% (1/23) in the DMBA+ 85 mg triacylglycerol group and 0% (0/24) in the DMBA+ vehicle-treated group. The results indicate that DAG-rich oil has promoting potential for skin carcinogenesis, and thus, further investigations of its tumor-promoting potential in other organs are warranted.

Periodic analysis of urethane-induced pulmonary tumors in living A/J mice by respiration-gated X-ray microcomputed tomography.

X-ray microcomputed tomography (micro-CT) with a respiratory gating system is a useful non-invasive approach to evaluate lung tumor development in living animal models. Here micro-CT was applied for the detection of lung lesions induced by a single intraperitoneal injection (250 mg/kg) of urethane in male A/J mice, at 2-week intervals from 10 to 30 weeks after carcinogen exposure. In micro-CT cross sections, lung tumor images were easily distinguished from surrounding non-tumorous tissues, the smallest detected tumor being approximately 0.5 mm in diameter. All of the urethane-treated mice (n = 15) developed lung tumors and the number of tumors developed in each mouse was 8.6 +/- 3.9. Six tumors, determined histopathologically to be adenocarcinomas, were detected, growing at different rates during the experimental period. The most aggressive carcinoma, increasing in diameter from 0.9 to 3.5 mm within 8 weeks, was a solid-type nodule with a clear tumor margin on the micro-CT imaging. Other tumors, histopathologically adenomas, grew slowly or moderately. The results provide evidence that micro-CT is a useful non-invasive imaging approach for evaluating the characteristics and growth of lung tumors in mice.