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"Ota, Yosuke"
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Tumor eradication by triplet therapy with BRAF inhibitor, TLR 7 agonist, and PD‐1 antibody for BRAF‐mutated melanoma
2024
Programmed death 1 (PD‐1)/programmed death‐ligand 1 inhibitors are commonly used to treat various cancers, including melanoma. However, their efficacy as monotherapy is limited, and combination immunotherapies are being explored to improve outcomes. In this study, we investigated a combination immunotherapy involving an anti‐PD‐1 antibody that blocks the major adaptive immune‐resistant mechanisms, a BRAF inhibitor that inhibits melanoma cell proliferation, and multiple primary immune‐resistant mechanisms, such as cancer cell‐derived immunosuppressive cytokines, and a Toll‐like receptor 7 agonist that enhances innate immune responses that promote antitumor T‐cell induction and functions. Using a xenogeneic nude mouse model implanted with human BRAF‐mutated melanoma, a BRAF inhibitor vemurafenib was found to restore T‐cell‐stimulatory activity in conventional dendritic cells by reducing immunosuppressive cytokines, including interleukin 6, produced by human melanoma. Additionally, intravenous administration of the Toll‐like receptor 7 agonist DSR6434 enhanced tumor growth inhibition by vemurafenib through stimulating the plasmacytoid dendritic cells/interferon‐α/natural killer cell pathways and augmenting the T‐cell‐stimulatory activity of conventional dendritic cells. In a syngeneic mouse model implanted with murine BRAF‐mutated melanoma, the vemurafenib and DSR6434 combination synergistically augmented the induction of melanoma antigen gp100‐specific T cells and inhibited tumor growth. Notably, only triplet therapy with vemurafenib, DSR6434, and the anti‐PD‐1 antibody resulted in complete regression of SIY antigen‐transduced BRAF‐mutated melanoma in a CD8 T‐cell‐dependent manner. These findings indicate that a triple‐combination strategy targeting adaptive and primary resistant mechanisms while enhancing innate immune responses that promote tumor‐specific T cells may be crucial for effective tumor eradication.
In this study, our aim was to develop an effective combination immunotherapy for patients with BRAF‐mutated melanoma by targeting three essential pathways involved in the induction and function of antitumor T cells. In a syngeneic mouse BRAF‐mutated melanoma model, triplet therapy with DSR6424, vemurafenib, and an anti‐PD‐1 antibody was found to effectively eradicate the BRAF‐mutated melanoma among various doublet combination therapies.
Journal Article
TLR7 agonist, DSP-0509, with radiation combination therapy enhances anti-tumor activity and modulates T cell dependent immune activation
by
Murata, Masashi
,
Nagai, Yasuhiro
,
Yamamoto, Setsuko
in
Adaptive immunity
,
Agonists
,
Allergology
2024
Background
TLR7 is a key player in the antiviral immunity. TLR7 signaling activates antigen-presenting cells including DCs and macrophages. This activation results in the adaptive immunity including T cells and B cells. Therefore, TLR7 is an important molecule of the immune system. Based on these observations, TLR7 agonists considered to become a therapy weaponize the immune system against cancer. Radiation therapy (RT) is one of the standard cancer therapies and is reported to modulate the tumor immune response. In this study, we aimed to investigate the anti-tumor activity in combination of TLR7 agonist, DSP-0509, with RT and underlying mechanism.
Result
We showed that anti-tumor activity is enhanced by combining RT with the TLR7 agonist DSP-0509 in the CT26, LM8, and 4T1 inoculated mice models. We found that once- weekly (q1w) dosing of DSP-0509 rather than biweekly (q2w) dosing is needed to achieve superior anti-tumor activities in CT26 model. Spleen cells from the mice in RT/DSP-0509 combination treatment group showed increased tumor lytic activity, inversely correlated with tumor volume, as measured by the chromium-release cytotoxicity assay. We also found the level of cytotoxic T lymphocytes (CTLs) increased in the spleens of completely cured mice. When the mice completely cured by combination therapy were re-challenged with CT26 cells, all mice rejected CT26 cells but accepted Renca cells. This rejection was not observed with CD8 depletion. Furthermore, levels of splenic effector memory CD8 T cells were increased in the combination therapy group. To explore the factors responsible for complete cure by combination therapy, we analyzed peripheral blood leukocytes (PBLs) mRNA from completely cured mice. We found that Havcr2
low
, Cd274
low
, Cd80
high
, and Il6
low
were a predictive signature for the complete response to combination therapy. An analysis of tumor-derived mRNA showed that combination of RT and DSP-0509 strongly increased the expression of anti-tumor effector molecules including Gzmb and Il12.
Conclusion
These data suggest that TLR7 agonist, DSP-0509, can be a promising concomitant when used in combination with RT by upregulating CTLs activity and gene expression of effector molecules. This combination can be an expecting new radio-immunotherapeutic strategy in clinical trials.
Journal Article
Identification of Highly Selective and Potent Histone Deacetylase 3 Inhibitors Using Click Chemistry-Based Combinatorial Fragment Assembly
by
Suzuki, Takayoshi
,
Zhan, Peng
,
Nakagawa, Hidehiko
in
Acetylation
,
Alkynes
,
Anticancer properties
2013
To find histone deacetylase 3 (HDAC3)-selective inhibitors, a series of 504 candidates was assembled using \"click chemistry\", by reacting nine alkynes bearing a zinc-binding group with 56 azide building blocks in the presence of Cu(I) catalyst. Screening of the 504-member triazole library against HDAC3 and other HDAC isozymes led to the identification of potent and selective HDAC3 inhibitors T247 and T326. These compounds showed potent HDAC3 inhibition with submicromolar IC50s, whereas they did not strongly inhibit other isozymes. Compounds T247 and T326 also induced a dose-dependent selective increase of NF-κB acetylation in human colon cancer HCT116 cells, indicating selective inhibition of HDAC3 in the cells. In addition, these HDAC3-selective inhibitors induced growth inhibition of cancer cells, and activated HIV gene expression in latent HIV-infected cells. These findings indicate that HDAC3-selective inhibitors are promising candidates for anticancer drugs and antiviral agents. This work also suggests the usefulness of the click chemistry approach to find isozyme-selective HDAC inhibitors.
Journal Article
Pelvic insufficiency fracture after definitive radiotherapy for uterine cervical cancer: retrospective analysis of risk factors
2013
The purpose of this study is to determine the incidence, clinical characteristics and risk factors of postradiation pelvic insufficiency fracture (PIF) in women with uterine cervical cancer. We reviewed the medical records of 126 patients who received definitive radiotherapy (RT) for uterine cervical cancer between 2003 and 2009 at our institution. Among them, 99 patients who underwent at least one computed tomography (CT) or magnetic resonance imaging of the pelvis during their follow-up at more than 6 months were included in this analysis. The relationship between the incidence of PIF and several patient- and treatment-related factors was analyzed. The median follow-up period was 21 months. Of the 126 patients, 33 (with a total of 50 lesions) were diagnosed with PIF. The 2-year cumulative incidence was 32%. Univariate analysis showed that age ≥70 years (P= 0.0010), postmenopausal state (P = 0.0013), and lower CT density of bone and bone marrow (P= 0.020) significantly related to PIF. In a multivariate analysis, of the 59 patients whose CT densities were evaluable, lower CT density was the only significant factor associated with PIF (P = 0.0026). In conclusion, postradiation PIFs were detected in a considerable number of patients after definitive RT for cervical cancer. Predisposing factors were older age, postmenopausal state, and decreased density of bone and bone marrow on CT.
Journal Article
DSP-0509, a systemically available TLR7 agonist, exhibits combination effect with immune checkpoint blockade by activating anti-tumor immune effects
by
Murata, Masashi
,
Umehara, Hiroki
,
Nagai, Yasuhiro
in
Adjuvants, Immunologic - pharmacology
,
Agonists
,
Animal models
2023
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.
Journal Article
A phase II study of adaptive two-step intensity-modulated radiation therapy (IMRT) with chemotherapy for loco-regionally advanced nasopharyngeal cancer (JCOG1015)
2020
BackgroundA phase II study of adaptive two-step intensity-modulated radiotherapy (IMRT) with chemotherapy for nasopharyngeal cancer (NPC) (JCOG1015) was conducted to evaluate the efficacy and safety.MethodsPatients aged 20–75 years with stages II–IVB NPC were enrolled. As adaptive two-step IMRT, computed tomography planning was performed twice before IMRT for the initial plan of 46 Gy/23 fractions and during treatment for the boost plan of 24 Gy/12 fractions with a total dose of 70 Gy. Chemotherapy (cisplatin 80 mg/m2/3-weeks × 3 courses) was administered concurrently with IMRT, followed by adjuvant chemotherapy (cisplatin at 70 mg/m2 with 5-FU 700 at mg/m2 for 5 days/4 weeks × 3 courses).ResultsBetween 2011 and 2014, 75 patients were enrolled from 12 institutions. The 3-year overall survival (OS) for the 75 patients was 88%, and the upper and lower limits of the 95% CI of 78%–94% were higher than the expected 3-year OS of 75% for the target population adjusted by the actual proportion of stage II:III:IV = 21%:44%:35%. The 3-year progression-free survival (PFS) and loco-regional PFS were 71% [59–80%] and 77% [66–85%], respectively. Although no grade 4–5 late toxicities were observed, 15 patients (20%) developed grade 3 late toxicities. Grade 2 xerostomia was noted in 26%, 12%, and 9% at 1, 2, and 3 years after starting IMRT, respectively.ConclusionsAdaptive two-step IMRT for NPC demonstrated an excellent 3-year OS with acceptable toxicities. This method may be one treatment option for locally advanced NPC.
Journal Article
A prospective picture collection study for a grading atlas of radiation dermatitis for clinical trials in head-and-neck cancer patients
by
Ohe, Yuichiro
,
Uchitomi, Yosuke
,
Tachibana, Hiroyuki
in
Cancer
,
Chemotherapy
,
Clinical trials
2016
Radiation dermatitis is one of the most common acute toxicities of both radiotherapy and chemoradiotherapy. Many clinical trials have evaluated the level of toxicity using the Common Terminology Criteria for Adverse Events ver. 4.03. This criterion accounts for severity in a single sentence only, and no visual classification guide has been available. Thus, there is a risk of subjective interpretation by the individual investigator. This contrasts with the situation with hematologic toxicities, which can be interpreted objectively. The aim of this prospective picture collection study was to develop a grading tool for use in establishing the severity of radiation dermatitis in clinical trials. A total of 118 patients who were scheduled to receive definitive or postoperative radiotherapy or chemoradiotherapy were enrolled from the four participating cancer centers. All researchers in our group used the same model of camera under the same shooting conditions to maintain consistent photographic quality. In all, 1600 photographs were collected. Of these, 100 photographs qualified for the first round of selection and were then graded by six experts, basically in accordance with the CTCAE ver. 4.03 (JCOG ver. in Japanese). After further study, 38 photographs were selected as representing typical models for Grade 1–4 radiation dermatitis; the radiation dermatitis grading atlas was produced from these photographs. The atlas will play a major role in ensuring that the dermatitis rating system is consistent between the institutions participating in trials. We hope that this will contribute to improving the quality of clinical trials, and also to improving the level of routine clinical practice.
Journal Article
Organs-at-risk dose constraints in head and neck intensity-modulated radiation therapy using a dataset from a multi-institutional clinical trial (JCOG1015A1)
by
Nakata, Kensei
,
Teshima, Teruki
,
Akimoto, Tetsuo
in
Artificial intelligence in Cancer imaging and diagnosis
,
Biomedical and Life Sciences
,
Biomedicine
2022
Background
JCOG1015A1 is an ancillary research study to determine the organ-specific dose constraints in head and neck carcinoma treated with intensity-modulated radiation therapy (IMRT) using data from JCOG1015.
Methods
Individual patient data and dose-volume histograms of organs at risk (OAR) were collected from 74 patients with nasopharyngeal carcinoma treated with IMRT who enrolled in JCOG1015. The incidence of late toxicities was evaluated using the cumulative incidence method or prevalence proportion. ROC analysis was used to estimate the optimal DVH cut-off value that predicted toxicities.
Results
The 5-year cumulative incidences of Grade (G) 1 myelitis, ≥ G1 central nervous system (CNS) necrosis, G2 optic nerve disorder, ≥ G2 dysphagia, ≥ G2 laryngeal edema, ≥ G2 hearing impaired, ≥ G2 middle ear inflammation, and ≥ G1 hypothyroidism were 10%, 5%, 2%, 11%, 5%, 26%, 34%, and 34%, respectively. Significant associations between DVH parameters and incidences of toxicities were observed in the brainstem for myelitis (D1cc ≥ 55.8 Gy), in the brain for CNS necrosis (D1cc ≥ 72.1 Gy), in the eyeball for optic nerve disorder (Dmax ≥ 36.6 Gy), and in the ipsilateral inner ear for hearing impaired (Dmean ≥ 44 Gy). The optic nerve, pharyngeal constrictor muscle (PCM), and thyroid showed tendencies between DVH parameters and toxicity incidence. The prevalence proportion of G2 xerostomia at 2 years was 17 versus 6% (contralateral parotid gland Dmean ≥ 25.8 Gy vs less).
Conclusions
The dose constraint criteria were appropriate for most OAR in this study, although more strict dose constraints might be necessary for the inner ear, PCM, and brainstem.
Journal Article
Real-world clinical outcomes in Japanese patients with locally advanced squamous cell carcinoma of the head and neck treated with radiotherapy plus cetuximab: a prospective observational study (JROSG12-2)
by
Monden, Nobuya
,
Fujii, Hirofumi
,
Shimokawa, Mototsugu
in
Chemotherapy
,
Clinical outcomes
,
Comorbidity
2022
BackgroundRadiotherapy plus cetuximab (bioradiotherapy: BRT) is a standard option in the treatment of locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN). Published data on its safety and efficacy in real-world settings is limited. Here, we conducted a prospective multi-institutional observational study to evaluate clinical outcomes of BRT in patients with LA-SCCHN.MethodsWe analyzed real-world data of all patients who underwent BRT from 2013 to 2016. The primary endpoint was 1-year progression-free survival (PFS). Secondary endpoints were 1-year locoregional PFS (LPFS), treatment completion rate (TCR), and adverse events (AEs).ResultsA total of 171 patients with a minimum 1-year follow-up were analyzed. Median age was 67 (36–85) years, and 37 patients (21.6%) were aged 75 years or older. 1-year PFS and LPFS were 51.5 and 56.1%, respectively. N stage (p = 0.049) was significantly associated with PFS. TCR was 77.2%. Cetuximab was definitively discontinued in 30 patients (17.5%), in 15 cases due to severe mucositis. N stage, T stage, and comorbidity were significantly associated with TCR. Major AEs of grade 3 or higher were pharyngeal mucositis (48.5%), radiation dermatitis (45.6%), and oral mucositis (40.4%). Pneumonitis was observed in 12 patients (7.0%); 6 cases (3.5%) were grades 3–4 and 2 (1.2%) were grade 5.ConclusionAs a result of the large number of elderly patients in clinical practice, toxicity reduced TCR. BRT-induced pneumonitis, which is sometimes fatal, was found to be more frequent than with chemotherapy plus cetuximab.
Journal Article
A Japanese multi-institutional phase II study of moderate hypofractionated intensity-modulated radiotherapy with image-guided technique for prostate cancer
by
Saito, Yoshihiro
,
Shikama, Naoto
,
Kozuka, Takuyo
in
Prostate cancer
,
Radiation therapy
,
Survival
2024
BackgroundThe aim of this multi-institutional phase II study was to confirm the safety and the potential efficacy of moderately hypofractionated intensity-modulated radiotherapy (IMRT) with prostate-based image-guidance for Japanese patients.MethodsPatients with low- or intermediate-risk localized prostate cancer were eligible. Patients with a part of high risk (having only one of the following factors, cT3a, 20 < PSA ≤ 30, or GS = 8 or 9) were also included. Hypofractionated IMRT using daily image-guided technique with prostate matching was performed with a total dose of 70 Gy in 28 fractions. Neoadjuvant hormonal therapy for 4–8 months was mandatory for patients with intermediate or high-risk prostate cancer.ResultsFrom 20 institutions, 134 patients enrolled. The median follow-up was 5.16 years (range, 1.43–6.47 years). The number of patients with low, intermediate, and high-risk prostate cancer was 20, 80, and 34, respectively. The 5-year overall, biochemical failure-free, and clinical failure-free survival was 94.5%, 96.0%, and 99.2%, respectively. The 5-year biochemical failure-free survival for patients with low-, intermediate-, and high-risk disease was 94.1%, 97.4%, and 93.9%, respectively. The incidences of grade 2 gastrointestinal (GI) and genitourinary (GU) late toxicities at 5 years were 5.3% and 5.3%, respectively. There are no acute or late toxicities ≥ grade 3. Of 124 patients who were followed for up to 5 years, the grade 2 late GU or GI toxicities were 10.5% (90% confidence intervals, 6.3–16.2%, p = 0.0958).ConclusionThe safety and efficacy of moderately hypofractionated IMRT with prostate-based image-guidance was confirmed among Japanese patients with prostate cancer.
Journal Article