Publications by authors named "Hideaki Tahara"

78 Publications

Establishment of organoids using residual samples from saline flushes during endoscopic ultrasound-guided fine-needle aspiration in patients with pancreatic cancer.

Endosc Int Open 2022 Jan 11;10(1):E82-E87. Epub 2022 Jan 11.

Department of Cancer Drug Discovery and Development, Research Center, Osaka International Cancer Institute, Osaka, Japan.

In patients with pancreatic cancer (PC), patient-derived organoid cultures can be useful tools for personalized drug selection and preclinical evaluation of novel therapies. To establish a less invasive method of creating organoids from a patient's tumor, we examined whether PC organoids can be established using residual samples from saline flushes (RSSFs) during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Five patients with PC who underwent EUS-FNA were enrolled in a prospective study conducted at our institution. RSSFs obtained during EUS-FNA procedures were collected. An organoid culture was considered as established when ≥ 5 passages were successful. Organoid-derived xenografts were created using established organoids. EUS-FNA was performed using a 22- or 25-gauge lancet needle without complications. Patient-derived organoids were successfully established in four patients (80.0 %) with the complete medium and medium for the selection of mutants. Organoid-derived xenografts were successfully created and histologically similar to EUS-FNA samples. Patient-derived PC organoids were successfully established using EUS-FNA RSSFs, which are produced as a byproduct of standard manipulations, but are usually not used for diagnosis. This method can be applied to all patients with PC, without additional invasive procedures, and can contribute to the development of personalized medicine and molecular research.
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http://dx.doi.org/10.1055/a-1713-3404DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8752201PMC
January 2022

Conversion Surgery for Advanced Thoracic SMARCA4-Deficient Undifferentiated Tumor With Atezolizumab in Combination With Bevacizumab, Paclitaxel, and Carboplatin Treatment: A Case Report.

JTO Clin Res Rep 2021 Nov 6;2(11):100235. Epub 2021 Oct 6.

Department of Thoracic Oncology, Osaka International Cancer Institute, Osaka, Japan.

A SMARCA4-deficient undifferentiated tumor (SMARCA4-UT) is a rapidly progressing subtype of lung cancer with a poor prognosis and causes early postoperative recurrence among operable patients. In this study, we present a case of SMARCA4-UT with vertebral and chest wall invasion that successfully underwent conversion surgery after treatment with atezolizumab in combination with bevacizumab, paclitaxel, and carboplatin. The surgical specimen comprised SMARCA4-deficient and SMARCA2-positive adenocarcinoma, confirming intratumor heterogeneity. Gene panel analysis revealed no substantial differences in mutant gene profiles among tumors and no differences in mutations. Furthermore, no recurrence occurred for 9 months after surgery. Thus, this case illustrates the possibility of multidisciplinary treatment including neoadjuvant therapy with immunotherapy and conversion surgery for SMARCA4-UT.
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http://dx.doi.org/10.1016/j.jtocrr.2021.100235DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8551843PMC
November 2021

Potent anti-tumor effects of receptor-retargeted syncytial oncolytic herpes simplex virus.

Mol Ther Oncolytics 2021 Sep 19;22:265-276. Epub 2021 Aug 19.

Project Division of Cancer Biomolecular Therapy, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.

Most oncolytic virotherapy has thus far employed viruses deficient in genes essential for replication in normal cells but not in cancer cells. Intra-tumoral injection of such viruses has resulted in clinically significant anti-tumor effects on the lesions in the vicinity of the injection sites but not on distant visceral metastases. To overcome this limitation, we have developed a receptor-retargeted oncolytic herpes simplex virus employing a single-chain antibody for targeting tumor-associated antigens (RR-oHSV) and its modified version with additional mutations conferring syncytium formation (RRsyn-oHSV). We previously showed that RRsyn-oHSV exhibits preserved antigen specificity and an ∼20-fold higher tumoricidal potency relative to RR-oHSV. Here, we investigated the anti-tumor effects of RRsyn-oHSV using human cancer xenografts in immunodeficient mice. With only a single intra-tumoral injection of RRsyn-oHSV at very low doses, all treated tumors regressed completely. Furthermore, intra-venous administration of RRsyn-oHSV resulted in robust anti-tumor effects even against large tumors. We found that these potent anti-tumor effects of RRsyn-oHSV may be associated with the formation of long-lasting tumor cell syncytia not containing non-cancerous cells that appear to trigger death of the syncytia. These results strongly suggest that cancer patients with distant metastases could be effectively treated with our RRsyn-oHSV.
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http://dx.doi.org/10.1016/j.omto.2021.08.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8426171PMC
September 2021

Combination Treatment of Topical Imiquimod Plus Anti-PD-1 Antibody Exerts Significantly Potent Antitumor Effect.

Cancers (Basel) 2021 Aug 5;13(16). Epub 2021 Aug 5.

Department of Dermatology, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan.

The exact mechanisms of the imiquimod (IMQ)-induced antitumor effect have not been fully understood. Although both topical IMQ treatment and anti-PD-1 antibody may be used for primary skin lesions or skin metastases of various cancers, the efficacy of each monotherapy for these lesions is insufficient. Using a murine tumor model and human samples, we aimed to elucidate the detailed mechanisms of the IMQ-induced antitumor effect and analyzed the antitumor effect of combination therapy of topical IMQ plus anti-PD-1 antibody. Topical IMQ significantly suppressed the tumor growth of MC38 in wildtype mice. IMQ upregulated interferon γ (IFN-γ) expression in CD8 T cells in both the lymph nodes and the tumor, and the antitumor effect was abolished in both Rag1-deficient mice and IFN-γ-deficient mice, indicating that IFN-γ produced by CD8 T cells play a crucial role in the IMQ-induced antitumor effect. IMQ also upregulated PD-1 expression in T cells as well as PD-L1/PD-L2 expression in myeloid cells, suggesting that IMQ induces not only T-cell activation but also T-cell exhaustion by enhanced PD-1 inhibitory signaling. Combination therapy of topical IMQ plus anti-PD-1 antibody exerted a significantly potent antitumor effect when compared with each single therapy, indicating that the combination therapy is a promising therapy for the skin lesions of various cancers.
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http://dx.doi.org/10.3390/cancers13163948DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8391905PMC
August 2021

NKG2D defines tumor-reacting effector CD8 T cells within tumor microenvironment.

Cancer Sci 2021 Sep 28;112(9):3484-3490. Epub 2021 Jul 28.

Institute of Natural Medicine, University of Toyama, Toyama, Japan.

For successful immunotherapy for cancer, it is important to understand the immunological status of tumor antigen-specific CD8 T cells in the tumor microenvironment during tumor progression. In this study, we monitored the behavior of B16OVA-Luc cells in mice immunized with a model tumor antigen ovalbumin (OVA). Using bioluminescence imaging, we identified the time series of OVA-specific CD8 T-cell responses during tumor progression: initial progression, immune control, and the escape phase. As a result of analyzing the status of tumor antigen-specific CD8 cells in those 3 different phases, we found that the expression of NKG2D defines tumor-reacting effector CD8 T cells. NKG2D may control the fate and TOX expression of tumor-reacting CD8 T cells, considering that NKG2D blockade in OVA-vaccinated mice delayed the growth of the B16OVA-Luc2 tumor and increased the presence of tumor-infiltrating OVA-specific CD8 T cells.
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http://dx.doi.org/10.1111/cas.15050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8409295PMC
September 2021

Atezolizumab with bevacizumab, paclitaxel and carboplatin was effective for patients with SMARCA4-deficient thoracic sarcoma.

Immunotherapy 2021 07 25;13(10):799-806. Epub 2021 May 25.

Department of Thoracic Oncology, Osaka International Cancer Institute, Osaka, Japan.

SMARCA4-deficient thoracic sarcoma (DTS) is a recently noted progressive thoracic malignancy. We recently experienced three cases of SMARCA4-DTS who were treated with atezolizumab in combination with bevacizumab, paclitaxel and carboplatin (ABCP) as the first-line therapy. Immunohistopathological analysis revealed absent expression of SMARCA4 in all cases. The tumor mutational burden was over 11/Mb and mutations in and were detected in all three cases. Partial response to ABCP treatment was observed in all three cases, with a progression-free survival of approximately 6 months or longer and a continuous response of 1 year or longer in one case. The first-line ABCP treatment demonstrated durable efficacy in SMARCA4-DTS regardless of the degree of PD-L1 expression.
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http://dx.doi.org/10.2217/imt-2020-0311DOI Listing
July 2021

Clinical significance of CD8 and FoxP3 tumor-infiltrating lymphocytes and MFG-E8 expression in lower rectal cancer with preoperative chemoradiotherapy.

Mol Clin Oncol 2021 May 5;14(5):87. Epub 2021 Mar 5.

Division of Surgical Oncology, Department of Surgery, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan.

Preoperative chemoradiotherapy (CRT) for rectal cancer contributes to tumor down-staging and decreases locoregional recurrence. However, each patient shows a significantly different response to CRT. Therefore, the identification of predictive factors to CRT response would be beneficial to avoid unnecessary treatment. Cancer immunity in patients has been suggested to play an important role in the eradication of the tumor by CRT. In the present study, the utility of CD8 and forkhead box P3 (FoxP3) tumor-infiltrating lymphocytes (TILs) and the expression of a novel immuno-regulatory factor, lactadherin (MFG-E8), in predicting CRT effectiveness in patients with rectal cancer was examined. A total of 61 patients with rectal cancer, who underwent curative resection following CRT were included in the study. The numbers of CD8 and FoxP3 TILs in a biopsy taken before CRT and MFG-E8 expression level in the specimens obtained at the time of the surgery after CRT were examined using immunohistochemical staining, and their association with clinicopathological characteristics, including patient survival, was determined. The tumors with more CD8 TILs in the biopsy samples before CRT showed a significantly more favorable CRT response. The patients with tumors and a higher number of CD8 TILs before CRT also exhibited significantly longer disease-free and overall survival times. Higher MFG-E8 expression level in post-CRT specimens was significantly associated with favorable CRT response; however, no significant association was found with any other clinicopathological characteristics, including survival time. The number of CD8 TILs before CRT was a valuable predictor for CRT response and was associated with favorable prognosis in patients with lower rectal cancer and who were treated with CRT. High MFG-E8 expression level after CRT was also associated with a favorable CRT response.
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http://dx.doi.org/10.3892/mco.2021.2249DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7976375PMC
May 2021

Antibody Screening System Using a Herpes Simplex Virus (HSV)-Based Probe To Identify a Novel Target for Receptor-Retargeted Oncolytic HSVs.

J Virol 2021 04 12;95(9). Epub 2021 Apr 12.

Project Division of Cancer Biomolecular Therapy, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Herpes simplex virus (HSV) is a promising tool for developing oncolytic virotherapy. We recently reported a platform for receptor-retargeted oncolytic HSVs that incorporates single-chain antibodies (scFvs) into envelope glycoprotein D (gD) to mediate virus entry via tumor-associated antigens. Therefore, it would be useful to develop an efficient system that can screen antibodies that might mediate HSV entry when they are incorporated as scFvs into gD. We created an HSV-based screening probe by the genetic fusion of a gD mutant with ablated binding capability to the authentic HSV entry receptors and the antibody-binding C domain of streptococcal protein G. This engineered virus failed to enter cells through authentic receptors. In contrast, when this virus was conjugated with an antibody specific to an antigen on the cell membrane, it specifically entered cells expressing the cognate antigen. This virus was used as a probe to identify antibodies that mediate virus entry via recognition of certain molecules on the cell membrane other than authentic receptors. Using this method, we identified an antibody specific to epiregulin (EREG), which has been investigated mainly as a secreted growth factor and not necessarily for its precursor that is expressed in a transmembrane form. We constructed an scFv from the anti-EREG antibody for insertion into the retargeted HSV platform and found that the recombinant virus entered cells specifically through EREG expressed by the cells. This novel antibody-screening system may contribute to the discovery of unique and unexpected molecules that might be used for the entry of receptor-retargeted oncolytic HSVs. The tropism of the cellular entry of HSV is dependent on the binding of the envelope gD to one of its authentic receptors. This can be fully retargeted to other receptors by inserting scFvs into gD with appropriate modifications. In theory, upon binding to the engineered gD, receptors other than authentic receptors should induce a conformational change in the gD, which activates downstream mechanisms required for viral entry. However, prerequisite factors for receptors to be used as targets of a retargeted virus remain poorly understood, and it is difficult to predict which molecules might be suitable for our retargeted HSV construct. Our HSV-based probe will allow unbiased screening of antibody-antigen pairs that mediate virus entry and might be a useful tool to identify suitable pairs for our construct and to enhance our understanding of virus-cell interactions during infection by HSV and possibly other viruses.
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http://dx.doi.org/10.1128/JVI.01766-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8104110PMC
April 2021

The liposome of trehalose dimycolate extracted from M. bovis BCG induces antitumor immunity via the activation of dendritic cells and CD8 T cells.

Cancer Immunol Immunother 2021 Sep 11;70(9):2529-2543. Epub 2021 Feb 11.

Osaka City University, Osaka, Japan.

Intravesical Bovis bacillus Calmette-Guérin (BCG) therapy is the most effective immunotherapy for bladder cancer, but it sometime causes serious side effects because of its inclusion of live bacteria. It is necessary to develop a more active but less toxic immunotherapeutic agent. Trehalose 6,6'-dimycolate (TDM), the most abundant hydrophobic glycolipid of the BCG cell wall, has been reported to show various immunostimulatory activities such as granulomagenesis and adjuvant activity. Here, we developed cationic liposomes incorporating TDM purified from Mycobacterium bovis BCG Connaught, and we investigated the antitumor effect of the cationic liposome TDM (Lip-TDM). Lip-TDM exerted an antitumor effect in bladder cancer, colon cancer, and melanoma-bearing mouse models that was comparable or even superior to that of BCG, with no body weight loss or granuloma formation. The antitumor effect of Lip-TDM disappeared in two types of mice: those with depletion of CD8 T cells, and those with knockout of macrophage-inducible C-type lectin (Mincle) which recognize TDM. Lip-TDM treatment enhanced the maturation and migration of dendritic cells in the tumor microenvironment in a Mincle-dependent manner. Our results elucidate mechanisms that underlie Lip-TDM treatment and suggest that Lip-TDM has potential as a safe and effective treatment for various cancers.
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http://dx.doi.org/10.1007/s00262-021-02870-2DOI Listing
September 2021

ASK1 suppresses NK cell-mediated intravascular tumor cell clearance in lung metastasis.

Cancer Sci 2021 Apr 6;112(4):1633-1643. Epub 2021 Mar 6.

Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.

Tumor metastasis is the leading cause of death worldwide and involves an extremely complex process composed of multiple steps. Our previous study demonstrated that apoptosis signal-regulating kinase 1 (ASK1) deficiency in mice attenuates tumor metastasis in an experimental lung metastasis model. However, the steps of tumor metastasis regulated by ASK1 remain unclear. Here, we showed that ASK1 deficiency in mice promotes natural killer (NK) cell-mediated intravascular tumor cell clearance in the initial hours of metastasis. In response to tumor inoculation, ASK1 deficiency upregulated immune response-related genes, including interferon-gamma (IFNγ). We also revealed that NK cells are required for these anti-metastatic phenotypes. ASK1 deficiency augmented cytokine production chemoattractive to NK cells possibly through induction of the ligand for NKG2D, a key activating receptor of NK cells, leading to further recruitment of NK cells into the lung. These results indicate that ASK1 negatively regulates NK cell-dependent anti-tumor immunity and that ASK1-targeted therapy can provide a new tool for cancer immunotherapy to overcome tumor metastasis.
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http://dx.doi.org/10.1111/cas.14842DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8019214PMC
April 2021

Antimetastatic effects of thalidomide by inducing the functional maturation of peripheral natural killer cells.

Cancer Sci 2020 Aug 14;111(8):2770-2778. Epub 2020 Jul 14.

Institute of Natural Medicine, University of Toyama, Toyama, Japan.

Thalidomide and its analogues are known as immunomodulatory drugs (IMiDs) that possess direct antimyeloma effects, in addition to other secondary effects, including antiangiogenic, antiinflammatory, and immunomodulatory effects. Although the involvement of natural killer (NK) cells in the antitumor effects of IMiDs has been reported, it is unclear whether IMiDs inhibit cancer cell metastasis by regulating the antitumor function of NK cells. In this study, we examined the protective effects of thalidomide against cancer metastasis by focusing on its immunomodulatory effects through NK cells. Using experimental lung metastasis models, we found that pharmacological effects of thalidomide on host cells, but not its direct anticancer tumor effects, are responsible for the inhibition of lung metastases. To exert the antimetastatic effects of thalidomide, both γ-interferon (IFN-γ) production and direct cytotoxicity of NK cells were essential, without notable contribution from T cells. In thalidomide-treated mice, there was a significant increase in the terminally differentiated mature CD27 NK cells in the peripheral tissues and NK cells in thalidomide-treated mice showed significantly higher cytotoxicity and IFN-γ production. The NK cell expression of T-bet was upregulated by thalidomide treatment and the downregulation of glycogen synthase kinase-3β expression was observed in thalidomide-treated NK cells. Collectively, our study suggests that thalidomide induces the functional maturation of peripheral NK cells through alteration of T-bet expression to inhibit lung metastasis of cancer cells.
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http://dx.doi.org/10.1111/cas.14538DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7419051PMC
August 2020

Detection of Tiger Podoplanin Using the Anti-Cat Podoplanin Monoclonal Antibody PMab-52.

Monoclon Antib Immunodiagn Immunother 2018 Nov;37(5):224-228

1 Department of Antibody Drug Development, Tohoku University Graduate School of Medicine , Sendai, Japan .

Podoplanin (PDPN) is expressed in type I alveolar cells of lung but not in type II alveolar cells. PDPN is also known as a specific lymphatic endothelial cell marker because PDPN is not expressed in vascular endothelial cells. PDPNs of several animals have been characterized using specific anti-PDPN monoclonal antibodies (mAbs): PMab-1, PMab-2, PMab-32, PMab-38, PMab-44, and PMab-52 for mouse, rat, rabbit, dog, bovine, and cat PDPNs, respectively. In this study, we investigated the possible crossreaction between these anti-PDPN mAbs and tiger PDPN. Flow cytometry and western blot analyses revealed that the anti-cat PDPN mAb PMab-52 (IgM, kappa) reacted with tiger PDPN, which is overexpressed in Chinese hamster ovary-K1 cells. Using immunohistochemical analysis, type I alveolar cells of the tiger lung were strongly detected by PMab-52. These results indicate that PMab-52 may be useful for the detection of tiger PDPN.
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http://dx.doi.org/10.1089/mab.2018.0033DOI Listing
November 2018

Immunoregulatory influence of abundant MFG-E8 expression by esophageal cancer treated with chemotherapy.

Cancer Sci 2018 Nov 22;109(11):3393-3402. Epub 2018 Sep 22.

Department of Surgery and Bioengineering, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan.

Milk fat globule-epidermal growth factor factor 8 (MFG-E8) is secreted from macrophages and is known to induce immunological tolerance mediated by regulatory T cells. However, the roles of the MFG-E8 that is expressed by cancer cells have not yet been fully examined. Expression of MFG-E8 was examined using immunohistochemistry in surgical samples from 134 patients with esophageal squamous cell carcinoma. The relationships between MFG-E8 expression levels and clinicopathological factors, including tumor-infiltrating lymphocytes, were evaluated. High MFG-E8 expression was observed in 23.9% of the patients. The patients with tumors highly expressing MFG-E8 had a significantly higher percentage of neoadjuvant chemotherapy (NAC) history (P < .0001) and shorter relapse-free survival (P = 0.012) and overall survival (OS; P = .0047). On subgroup analysis, according to NAC history, patients with high MFG-E8 expression had significantly shorter relapse-free survival (P = .027) and OS (P = .0039) only when they had been treated with NAC. Furthermore, tumors with high MFG-E8 expression had a significantly lower ratio of CD8 T cells/regulatory T cells in tumor-infiltrating lymphocytes (P = .042) only in the patients treated with NAC, and those with a lower ratio had a shorter OS (P = .026). High MFG-E8 expression was also found to be an independent prognostic factor in multivariate analysis. The abundant MFG-E8 expression in esophageal squamous cell carcinoma might have a negative influence on the long-term survival of patients after chemotherapy by affecting T-cell regulation in the tumor microenvironment.
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http://dx.doi.org/10.1111/cas.13785DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6215892PMC
November 2018

Lung-resident natural killer cells control pulmonary tumor growth in mice.

Cancer Sci 2018 Sep 12;109(9):2670-2676. Epub 2018 Jul 12.

Division of Pathogenic Biochemistry, Department of Bioscience, Institute of Natural Medicine, University of Toyama, Toyama, Japan.

Accumulating evidence indicates the importance of natural killer (NK) cells in controlling tumor growth and metastasis. NK cell subsets display diversities in their function and tissue distribution and Mac-1 CD27 NK cells are the predominant population of lung-resident NK cells. Although the lung is a major organ where primary tumor develops and cancer cells metastasize, there is no clear evidence whether circulating NK cells and/or tissue-resident NK cells control tumor growth in the lung. In the present study, we examined an antitumor function of lung-resident NK cells to control pulmonary tumor growth. In an orthotopic lung tumor model, NK cells controlled pulmonary tumor growth, and mature circulating NK cell subsets were increased in tumor-bearing lungs through a C-X-C motif chemokine receptor 3 (CXCR3)-dependent mechanism. Although such increase in migratory NK cell subsets can be blocked by anti-CXCR3 treatment, there was no difference in pulmonary tumor growth in anti-CXCR3-treated mice compared with control mice. In addition to pulmonary tumor growth, lung-resident NK cells, but not migratory NK cells, play a dominant role in controlling metastatic growth of cancer cells in lung. These results strongly indicate an importance of lung-resident NK cells for controlling pulmonary tumor growth.
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http://dx.doi.org/10.1111/cas.13703DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6125475PMC
September 2018

Epitope Mapping of Monoclonal Antibody PMab-48 Against Dog Podoplanin.

Monoclon Antib Immunodiagn Immunother 2018 Jun 2;37(3):162-165. Epub 2018 Apr 2.

1 Department of Antibody Drug Development, Tohoku University Graduate School of Medicine , Sendai, Japan .

Podoplanin (PDPN), a type I transmembrane sialoglycoprotein, is expressed on normal renal podocytes, pulmonary type I alveolar cells, and lymphatic endothelial cells. Increased expression of PDPN in cancers is associated with poor prognosis and hematogenous metastasis through interactions with C-type lectin-like receptor 2 (CLEC-2) on platelets. We previously reported a novel PMab-48 antibody, which is an anti-dog PDPN (dPDPN) monoclonal antibody (mAb) recognizing PDPN expressed in lymphatic endothelial cells. However, the binding epitope of PMab-48 is yet to be clarified. In this study, an enzyme-linked immunosorbent assay and flow cytometry were used to investigate epitopes of PMab-48. The results revealed that the critical epitope of PMab-48 comprises Asp29, Asp30, Ile31, Ile32, and Pro33 of dPDPN.
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http://dx.doi.org/10.1089/mab.2018.0006DOI Listing
June 2018

Reply: Lymph stasis promotes tumor growth.

J Dermatol Sci 2018 06 15;90(3):367-368. Epub 2018 Feb 15.

Department of Surgery and Bioengineering, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan.

Our study suggested that surgical damage of the lymphatic system promotes tumor progression via impaired immune response. However, as pointed out by Valerio et al, lymph stasis is likely to induce immune stasis, resulting in not only enhanced tumor growth but also tumor generation. Although mechanisms of the tumor generation may not only include impaired immune response but also other factors induced by lymph stasis, we should avoid unnecessary lymphatic disruption in any surgeries and carefully consider the flap design to minimalize lymphatic disruption even in cases with benign tumors.
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http://dx.doi.org/10.1016/j.jdermsci.2018.02.011DOI Listing
June 2018

NK Cells Control Tumor-Promoting Function of Neutrophils in Mice.

Cancer Immunol Res 2018 03 23;6(3):348-357. Epub 2018 Jan 23.

Division of Pathogenic Biochemistry, Department of Bioscience, Institute of Natural Medicine, University of Toyama, Toyama, Japan.

Although natural killer (NK) cells are recognized as direct antitumor effectors, the ability of NK cells to control cancer-associated inflammation, which facilitates tumor progression, remains unknown. In this study, we demonstrate that NK cells control tumor-promoting inflammation through functional modification of neutrophils. NK cells control the tumor-promoting function of neutrophils through an IFNγ-dependent mechanism. Tumor progression in an NK cell-depleted host is diminished when the IL17A-neutrophil axis is absent. In NK cell-depleted mice, neutrophils acquire a tumor-promoting phenotype, characterized by upregulation of VEGF-A expression, which promotes tumor growth and angiogenesis. A VEGFR inhibitor which preferentially suppressed tumor growth in NK cell-depleted mice was dependent on neutrophils. Furthermore, the systemic neutropenia caused by an antimetabolite treatment showed an anticancer effect only in mice lacking NK cells. Thus, NK cells likely control the tumor-promoting and angiogenic function of neutrophils. .
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http://dx.doi.org/10.1158/2326-6066.CIR-17-0204DOI Listing
March 2018

Surgical damage to the lymphatic system promotes tumor growth via impaired adaptive immune response.

J Dermatol Sci 2018 Apr 29;90(1):46-51. Epub 2017 Dec 29.

Department of Dermatology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.

Background: Both lymph nodes (LNs) and lymphatic channels from primary sites to regional LNs are critical for initiation of adaptive immunity. However, as LNs are common metastatic sites in skin cancers, LN biopsies or dissections are frequently performed. In addition, reconstructive skin flaps after tumor resection may damage lymphatic flow from primary sites to regional LNs.

Objective: This study was designed to investigate the effect on tumor progression by such surgeries.

Methods: We developed a mouse model that simulates LNs dissection or skin flap that blocks lymphatic flow from primary sites to regional LNs and monitored tumor progression.

Results: As a poor immunogenic tumor line, the growth of inoculated B16F10 melanoma into syngeneic C57BL/6 mice was not affected by these surgeries. However, the growth of the same cell line in allogenic Balb/c mice was accelerated while immune cell infiltration (CD4 and CD8 T cells) into the tumor was reduced by these surgeries. In addition, both cytotoxicity against B16F10 melanoma and numbers of apoptotic tumor cells were diminished by these surgeries. Similarly, tumor growth of the immunogenic MC38 cell line in syngeneic C57BL/6 mice was accelerated and immune cell infiltration and apoptotic tumor cells were reduced by these surgeries.

Conclusion: These results strongly indicate that surgical damage of the lymphatic system may promote tumor progression via impaired adaptive immune response.
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http://dx.doi.org/10.1016/j.jdermsci.2017.12.016DOI Listing
April 2018

Cytokine biomarkers to predict antitumor responses to nivolumab suggested in a phase 2 study for advanced melanoma.

Cancer Sci 2017 May 11;108(5):1022-1031. Epub 2017 May 11.

Department of Surgery and Bioengineering, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Promising antitumor activities of nivolumab, a fully humanized IgG4 inhibitor antibody against the programmed death-1 protein, were suggested in previous phase 1 studies. The present phase 2, single-arm study (JAPIC-CTI #111681) evaluated the antitumor activities of nivolumab and explored its predictive correlates in advanced melanoma patients at 11 sites in Japan. Intravenous nivolumab 2 mg/kg was given repeatedly at 3-week intervals to 35 of 37 patients enrolled from December 2011 to May 2012 until they experienced unacceptable toxicity, disease progression, or complete response. Primary endpoint was objective response rate. Serum levels of immune modulators were assessed at multiple time points. As of 21 October 2014, median response duration, median progression-free survival, and median overall survival were 463 days, 169 days, and 18.0 months, respectively. The overall response rate and 1- and 2-year survival rates were 28.6%, 54.3%, and 42.9%, respectively. Thirteen patients remained alive at the end of the observation period and no deaths were drug related. Grade 3-4 drug-related adverse events were observed in 31.4% of patients. Pretreatment serum interferon-γ, and interleukin-6 and -10 levels were significantly higher in the patients with objective tumor responses than in those with tumor progression. In conclusion, giving repeated i.v. nivolumab had potent and durable antitumor effects and a manageable safety profile in advanced melanoma patients, strongly suggesting the usefulness of nivolumab for advanced melanoma and the usefulness of pretreatment serum cytokine profiles as correlates for predicting treatment efficacy.
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http://dx.doi.org/10.1111/cas.13226DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5448619PMC
May 2017

Antiglycopeptide Mouse Monoclonal Antibody LpMab-21 Exerts Antitumor Activity Against Human Podoplanin Through Antibody-Dependent Cellular Cytotoxicity and Complement-Dependent Cytotoxicity.

Monoclon Antib Immunodiagn Immunother 2017 Feb;36(1):20-24

1 Tohoku University Graduate School of Medicine , Sendai, Japan .

The interaction between podoplanin (PDPN) and C-type lectin-like receptor 2 (CLEC-2) is involved in tumor malignancy. We have established many monoclonal antibodies (mAbs) against human podoplanin using the cancer-specific mAb (CasMab) technology. LpMab-21, one of the mouse antipodoplanin mAbs, is of the IgG subclass, and its minimum epitope was determined to be Thr76-Arg79 of the human podoplanin. Importantly, sialic acid is linked to Thr76; therefore, LpMab-21 is an antiglycopeptide mAb (GpMab). In this study, we investigated whether LpMab-21 shows antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against human podoplanin-expressing cancer cell lines in vitro and also studied its antitumor activities using a xenograft model. LpMab-21 showed high ADCC and CDC activities against not only podoplanin-expressing Chinese hamster ovary cells but also LN319 glioblastoma cells and PC-10 lung cancer cells, both of which endogenously express podoplanin. Furthermore, LpMab-21 decreased tumor growth in vivo, indicating that LpMab-21 could be useful for antibody therapy against human podoplanin-expressing cancers.
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http://dx.doi.org/10.1089/mab.2016.0045DOI Listing
February 2017

Oncolytic Herpes Simplex Virus Vectors Fully Retargeted to Tumor- Associated Antigens.

Curr Cancer Drug Targets 2018 ;18(2):162-170

Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pennsylvania, PA, United States.

Oncolytic virotherapy is a novel therapeutic modality for malignant diseases that exploits selective viral replication in cancer cells. Herpes simplex virus (HSV) is a promising agent for oncolytic virotherapy due to its broad cell tropism and the identification of mutations that favor its replication in tumor over normal cells. However, these attenuating mutations also tend to limit the potency of current oncolytic HSV vectors that have entered clinical studies. As an alternative, vector retargeting to novel entry receptors has the potential to achieve tumor specificity at the stage of virus entry, eliminating the need for replication-attenuating mutations. Here, we summarize the molecular mechanism of HSV entry and recent advances in the development of fully retargeted HSV vectors for oncolytic virotherapy. Retargeted HSV vectors offer an attractive platform for the creation of a new generation of oncolytic HSV with improved efficacy and specificity.
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http://dx.doi.org/10.2174/1568009617666170206105855DOI Listing
May 2019

Chimeric Anti-Human Podoplanin Antibody NZ-12 of Lambda Light Chain Exerts Higher Antibody-Dependent Cellular Cytotoxicity and Complement-Dependent Cytotoxicity Compared with NZ-8 of Kappa Light Chain.

Monoclon Antib Immunodiagn Immunother 2017 Feb 3;36(1):25-29. Epub 2017 Feb 3.

1 Tohoku University Graduate School of Medicine , Sendai, Japan .

Podoplanin (PDPN), a type I transmembrane 36-kDa glycoprotein, is expressed not only in normal cells, such as renal epithelial cells (podocytes), lymphatic endothelial cells, and pulmonary type I alveolar cells, but also in cancer cells, including brain tumors and lung squamous cell carcinomas. Podoplanin activates platelet aggregation by binding to C-type lectin-like receptor-2 (CLEC-2) on platelets, and the podoplanin/CLEC-2 interaction facilitates blood/lymphatic vessel separation. We previously produced neutralizing anti-human podoplanin monoclonal antibody (mAb), clone NZ-1 (rat IgG, lambda), which neutralizes the podoplanin/CLEC-2 interaction and inhibits platelet aggregation and cancer metastasis. Human-rat chimeric antibody, NZ-8, was previously developed using variable regions of NZ-1 and human constant regions of heavy chain (IgG) and light chain (kappa chain). Although NZ-8 showed high antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against human podoplanin-expressing cancer cells, the binding affinity of NZ-8 was lower than that of NZ-1. Herein, we produced a novel human-rat chimeric antibody, NZ-12, the constant regions of which consist of IgG heavy chain and lambda light chain. Using flow cytometry, we demonstrated that the binding affinity of NZ-12 was much higher than that of NZ-8. Furthermore, ADCC and CDC activities of NZ-12 were significantly increased against glioblastoma cell lines (LN319 and D397) and lung cancer cell line (PC-10). These results suggested that NZ-12 could become a promising therapeutic antibody against podoplanin-expressing brain tumors and lung cancers.
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http://dx.doi.org/10.1089/mab.2016.0047DOI Listing
February 2017

Syncytial Mutations Do Not Impair the Specificity of Entry and Spread of a Glycoprotein D Receptor-Retargeted Herpes Simplex Virus.

J Virol 2016 Dec 28;90(24):11096-11105. Epub 2016 Nov 28.

Division of Bioengineering, Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Membrane fusion, which is the key process for both initial cell entry and subsequent lateral spread of herpes simplex virus (HSV), requires the four envelope glycoproteins gB, gD, gH, and gL. Syncytial mutations, predominantly mapped to the gB and gK genes, confer hyperfusogenicity on HSV and cause multinucleated giant cells, termed syncytia. Here we asked whether interaction of gD with a cognate entry receptor remains indispensable for initiating membrane fusion of syncytial strains. To address this question, we took advantage of mutant viruses whose viral entry into cells relies on the uniquely specific interaction of an engineered gD with epidermal growth factor receptor (EGFR). We introduced selected syncytial mutations into gB and/or gK of the EGFR-retargeted HSV and found that these mutations, especially when combined, enabled formation of extensive syncytia by human cancer cell lines that express the target receptor; these syncytia were substantially larger than the plaques formed by the parental retargeted HSV strain. We assessed the EGFR dependence of entry and spread separately by using direct entry and infectious center assays, respectively, and we found that the syncytial mutations did not override the receptor specificity of the retargeted viruses at either stage. We discuss the implications of these results for the development of more effective targeted oncolytic HSV vectors.

Importance: Herpes simplex virus (HSV) is investigated not only as a human pathogen but also as a promising agent for oncolytic virotherapy. We previously showed that both the initial entry and subsequent lateral spread of HSV can be retargeted to cells expressing tumor-associated antigens by single-chain antibodies fused to a receptor-binding-deficient envelope glycoprotein D (gD). Here we introduced syncytial mutations into the gB and/or gK gene of gD-retargeted HSVs to determine whether viral tropism remained dependent on the interaction of gD with the target receptor. Entry and spread profiles of the recombinant viruses indicated that gD retargeting does not abolish the hyperfusogenic activity of syncytial mutations and that these mutations do not eliminate the dependence of HSV entry and spread on a specific gD-receptor interaction. These observations suggest that syncytial mutations may be valuable for increasing the tumor-specific spreading of retargeted oncolytic HSV vectors.
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http://dx.doi.org/10.1128/JVI.01456-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5126368PMC
December 2016

IL-17A-producing CD30(+) Vδ1 T cells drive inflammation-induced cancer progression.

Cancer Sci 2016 Sep 1;107(9):1206-14. Epub 2016 Sep 1.

Laboratory of Cancer Biology and Molecular Immunology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Bunkyo-ku, Tokyo, Japan.

Although it has been suspected that inflammation is associated with increased tumor metastasis, the exact type of immune response required to initiate cancer progression and metastasis remains unknown. In this study, by using an in vivo tumor progression model in which low tumorigenic cancer cells acquire malignant metastatic phenotype after exposure to inflammation, we found that IL-17A is a critical cue for escalating cancer cell malignancy. We further demonstrated that the length of exposure to an inflammatory microenvironment could be associated with acquiring greater tumorigenicity and that IL-17A was critical for amplifying such local inflammation, as observed in the production of IL-1β and neutrophil infiltration following the cross-talk between cancer and host stromal cells. We further determined that γδT cells expressing Vδ1 semi-invariant TCR initiate cancer-promoting inflammation by producing IL-17A in an MyD88/IL-23-dependent manner. Finally, we identified CD30 as a key molecule in the inflammatory function of Vδ1T cells and the blockade of this pathway targeted this cancer immune-escalation process. Collectively, these results reveal the importance of IL-17A-producing CD30(+) Vδ1T cells in triggering inflammation and orchestrating a microenvironment leading to cancer progression.
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http://dx.doi.org/10.1111/cas.13005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5021032PMC
September 2016

Negative influence of programmed death-1-ligands on the survival of esophageal cancer patients treated with chemotherapy.

Cancer Sci 2016 Jun 16;107(6):726-33. Epub 2016 May 16.

Department of Surgery and Bioengineering, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan.

The programmed death-1/programmed death-1 ligands (PD-1/PD-L) pathway plays an important role in immunological tumor evasion. However, the clinical significance of the PD-L (L1 and L2) expression in esophageal cancer treated with chemotherapy has not been fully investigated. We examined the expression of PD-L of the primary tumors obtained from 180 esophageal cancer patients who underwent radical resection with or without neoadjuvant chemotherapy (NAC) using immunohistochemical staining. The relationship between the expression patterns and clinico-pathological characteristics was examined. In the present study, 53 patients (29.4%) and 88 patients (48.3%) were classified into positive for PD-L1 and PD-L2 expression, respectively. In all the patients examined, overall survival rates of the patients with tumors positive for PD-L1 or PD-L2 were significantly worse than those with tumors negative for PD-L1 or PD-L2 (P = 0.0010 and P = 0.0237, respectively). However, subgroup analysis showed that these tendencies are only found in the patients treated with NAC, and not in those without NAC. The patients with positive PD-L1 expression had a significantly higher rate of NAC history (P = 0.0139), but those with positive PD-L2 expression did not have a significantly high rate of NAC history (P = 0.6127). There is no significant relationship between PD-L1 expression and response to chemotherapy (P = 0.3118), but patients with positive PD-L2 expression had significantly inferior responses to chemotherapy (P = 0.0034). The PD-1/PD-L pathway might be an immunological mechanism associated with the long-term effectiveness of chemotherapy in esophageal cancer patients. Further investigation into the roles of PD-1 pathway in chemotherapy could lead to the development of better treatment options for this disease.
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http://dx.doi.org/10.1111/cas.12938DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4968603PMC
June 2016

Augmentation of Immune Checkpoint Cancer Immunotherapy with IL18.

Clin Cancer Res 2016 06 11;22(12):2969-80. Epub 2016 Jan 11.

Laboratory of Tumor Immunology and Immunotherapy, Hyogo College of Medicine, Hyogo, Japan.

Purpose: Recent clinical trials and animal models demonstrated that immune checkpoint blockade enhanced effector cell responses and tumor rejection; however, further development and improvement of cancer immunotherapy is necessary for more favorable objective responses. In this study, we examined the effect of IL18 on the antitumor effect of immune checkpoint inhibitors.

Experimental Design: We examined the effect of IL18 on the peritoneal dissemination of CT-26 cells or tail vein injection metastasis of B16/F10 cells using antiprogrammed death-1 ligand-1 (αPD-L1) and/or anti-CTL-associated antigen-4 (αCTLA-4) mAbs.

Result: Massive ascites developed after intraperitoneal inoculation of CT-26, resulting in animal death within 30 days. Treatment of mice with αPD-L1 and/or αCTLA-4 significantly prolonged their survival, and a combination of the antibodies and IL18 provided a much greater therapeutic benefit. The combination modality led to the accumulation of precursor of mature natural killer (pre-mNK) cells in the peritoneal cavity together with increased CD8(+) T and decreased CD4(+)CD25(+)Foxp3(+) T cells. Depletion of the pre-mNK cells abrogated the therapeutic effects and increased the number of CD4(+)CD25(+)Foxp3(+) T cells. The combination treatment also suppressed tail vein injection metastasis of B16/F10 cells.

Conclusions: The results demonstrated that IL18 enhanced therapeutic effects of immune checkpoint blockade against peritoneal dissemination of carcinoma or tail vein injection metastasis of melanoma through accumulation of pre-mNK cells, memory-type CD8(+) T cells, and suppression of CD4(+)CD25(+)Foxp3(+) T cells. A combination of immune checkpoint inhibitors with IL18 may give a suggestion to the development of next-generation cancer immunotherapy. Clin Cancer Res; 22(12); 2969-80. ©2016 AACR.
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http://dx.doi.org/10.1158/1078-0432.CCR-15-1655DOI Listing
June 2016

Putting the brakes on anticancer therapies: suppression of innate immune pathways by tumor-associated myeloid cells.

Trends Mol Med 2013 Sep 27;19(9):536-45. Epub 2013 Jun 27.

Research Center for Infection-associated Cancer, Institute for Genetic Medicine, Hokkaido University, Sapporo, 060-0815, Japan. Electronic address:

Accumulating evidence has revealed that immunogenic cell death triggered by particular chemotherapeutic agents plays a critical role in harnessing antitumor immunity to clinical responses. However, negative regulatory pathways exist which suppress the induction of effective immune responses by a broad spectrum of anticancer therapies including 'non-immunogenic' regimens. Tumor-associated myeloid cells are unique in that they are capable of manipulating responses to anticancer drugs by utilizing negative regulatory factors of innate immune pathways, including damage-associated molecule-mediated pattern recognition and tolerogenic phagocytosis. Further elucidation of the molecular mechanisms regulating innate immune responses of tumor-associated myeloid cells under cellular stress should enhance the development of new molecular targeting therapies for patients with treatment-refractory cancers.
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http://dx.doi.org/10.1016/j.molmed.2013.06.001DOI Listing
September 2013

[Mechanism of action for immunotherapy drugs].

Authors:
Hideaki Tahara

Nihon Rinsho 2012 Dec;70(12):2066-72

Department of Surgery and Bioengineering, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo.

Cancer therapy utilizing cellular immunity has been developed using various reagents including stimulus for innate immunity, cytokines, vaccines, autologous cells and gene-vectors. Recently, mono-clonal antibodies have been added to the list as well. These reagents of modalities have been developed base on the findings in the basic research in cellular immunology which has been proven to have potent activities to suppress the tumor growth in either in vitro or in vivo. This review describes the characteristics of the reagents of modalities focusing on their mechanisms of action.
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December 2012

Toll-like receptor 3 signaling converts tumor-supporting myeloid cells to tumoricidal effectors.

Proc Natl Acad Sci U S A 2012 Feb 19;109(6):2066-71. Epub 2012 Jan 19.

Department of Microbiology and Immunology, Graduate School of Medicine, Hokkaido University, Kita-ku, Sapporo 060-8638, Japan.

Smoldering inflammation often increases the risk of progression for malignant tumors and simultaneously matures myeloid dendritic cells (mDCs) for cell-mediated immunity. PolyI:C, a dsRNA analog, is reported to induce inflammation and potent antitumor immune responses via the Toll-like receptor 3/Toll-IL-1 receptor domain-containing adaptor molecule 1 (TICAM-1) and melanoma differentiation-associated protein 5/IFN-β promoter stimulator 1 (IPS-1) pathways in mDCs to drive activation of natural killer cells and cytotoxic T lymphocytes. Here, we found that i.p. or s.c. injection of polyI:C to Lewis lung carcinoma tumor-implant mice resulted in tumor regression by converting tumor-supporting macrophages (Mfs) to tumor suppressors. F4/80(+)/Gr1(-) Mfs infiltrating the tumor respond to polyI:C to rapidly produce inflammatory cytokines and thereafter accelerate M1 polarization. TNF-α was increased within 1 h in both tumor and serum upon polyI:C injection into tumor-bearing mice, followed by tumor hemorrhagic necrosis and growth suppression. These tumor responses were abolished in TNF-α(-/-) mice. Furthermore, F4/80(+) Mfs in tumors extracted from polyI:C-injected mice sustained Lewis lung carcinoma cytotoxic activity, and this activity was partly abrogated by anti-TNF-α Ab. Genes for supporting M1 polarization were subsequently up-regulated in the tumor-infiltrating Mfs. These responses were completely abrogated in TICAM-1(-/-) mice, and unaffected in myeloid differentiation factor 88(-/-) and IPS-1(-/-) mice. Thus, the TICAM-1 pathway is not only important to mature mDCs for cross-priming and natural killer cell activation in the induction of tumor immunity, but also critically engaged in tumor suppression by converting tumor-supporting Mfs to those with tumoricidal properties.
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http://dx.doi.org/10.1073/pnas.1113099109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3277567PMC
February 2012

[Gene therapy for colorectal cancer].

Nihon Rinsho 2011 Apr;69 Suppl 3:564-8

Department of Surgery and Bioengineering, Institute of Medical Science, The University of Tokyo.

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April 2011
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