Kiuchi Yuji

Prof. Dr. Kiuchi Yuji


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 December 2021 in Biomedicines
Verified
Journal Article
Open access
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RORyotaro Ohkuma
Ryotaro Ohkuma
KIKatsuaki Ieguchi
Katsuaki Ieguchi
MWMakoto Watanabe
Makoto Watanabe
DTDaisuke Takayanagi
Daisuke Takayanagi
TGTsubasa Goshima
Tsubasa Goshima
Satoshi WADASatoshi WADA
Satoshi WADA
Immune checkpoint inhibitors (ICIs) confer remarkable therapeutic benefits to patients with various cancers. However, many patients are non-responders or develop resistance following an initial response to ICIs. There are no reliable biomarkers to predict the therapeutic effect of ICIs. Therefore, this study investigated the clinical implications of plasma levels of soluble anti-programmed death-1 (sPD-1) in patients with cancer treated with ICIs. In total, 22 patients (13 with non-small-cell lung carcinoma, 8 with gastric cancer, and 1 with bladder cancer) were evaluated for sPD-1 concentration using enzyme-linked immunosorbent assays for diagnostic and anti-PD-1 antibody analyses. sPD-1 levels were low before the administration of anti-PD-1 antibodies. After two and four cycles of anti-PD-1 antibody therapy, sPD-1 levels significantly increased compared with pretreatment levels (p = 0.0348 vs. 0.0232). We observed an increased rate of change in plasma sPD-1 concentrations after two and four cycles of anti-PD-1 antibody therapy that significantly correlated with tumor size progression (p = 0.024). sPD-1 may be involved in resistance to anti-PD-1 antibody therapy, suggesting that changes in sPD-1 levels can identify primary ICI non-responders early in treatment. Detailed analysis of each cancer type revealed the potential of sPD-1 as a predictive biomarker of response to ICI treatment in patients with cancer.

Verified
Journal Article
Open access
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KIKatsuaki Ieguchi
Katsuaki Ieguchi
MFMasabumi Funakoshi
Masabumi Funakoshi
TMTaishi Mishima
Taishi Mishima
KTKohtaro Takizawa
Kohtaro Takizawa
TOTsutomu Omori
Tsutomu Omori
Satoshi WADASatoshi WADA
Satoshi WADA
Emerging evidence suggests that neural activity contributes to tumor initiation and its acquisition of metastatic properties. More specifically, it has been reported that the sympathetic nervous system regulates tumor angiogenesis, tumor growth, and metastasis. The function of the sympathetic nervous system in primary tumors has been gradually elucidated. However, its functions in pre-metastatic environments and/or the preparation of metastatic environments far from the primary sites are still unknown. To investigate the role of the sympathetic nervous system in pre-metastatic environments, we performed chemical sympathectomy using 6-OHDA in mice and observed a decrease in lung metastasis by attenuating the recruitment of myeloid-derived suppressor cells. Furthermore, we note that neuro-immune cell interactions could be observed in tumor-bearing mouse lungs in conjunction with the decreased expression of Sema3A. These data indicate that the sympathetic nervous system contributes to the preparation of pre-metastatic microenvironments in the lungs, which are mediated by neuro-immune cell interactions.

10 December 2025 in Biomedicines
Verified
Journal Article
Open access
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リスリサコ スズキ
リサコ スズキ
RORyotaro Ohkuma
Ryotaro Ohkuma
MWMakoto Watanabe
Makoto Watanabe
EMEmiko Mura
Emiko Mura
TTToshiaki Tsurui
Toshiaki Tsurui
Satoshi WADASatoshi WADA
Satoshi WADA
Background/Objectives: Immune checkpoint inhibitors (ICIs) have transformed cancer therapy; however, their efficacy varies among patients. Eosinophils have been reported as prognostic markers in chemotherapy-treated pancreatic cancer; however, these studies are limited mainly to single cancer types and relatively small cohorts. Therefore, we aimed to examine the relationship between eosinophil count and the effectiveness of ICIs across various cancer types. Methods: We retrospectively analyzed 138 patients treated with ICI monotherapy, ICI plus chemotherapy, or chemotherapy alone at our institution between December 2015 and September 2024. Peripheral blood parameters, including eosinophil counts and albumin levels, were collected at baseline and after two cycles of treatment. Associations between overall survival (OS) and progression-free survival (PFS) were assessed using Kaplan–Meier analysis and Cox proportional hazards regression. Results: In the ICI monotherapy group, patients with higher baseline eosinophil counts had significantly longer OS (HR 0.26, p = 0.007) and PFS (HR 0.30, p = 0.005). No significant associations were observed between the ICI plus chemotherapy and chemotherapy-alone groups. Changes in eosinophil counts between baseline and after two cycles were not associated with outcomes in any group. Conclusions: Baseline eosinophil counts were significantly associated with survival outcomes in patients receiving ICI monotherapy and may serve as a promising predictive biomarker.

Verified
Journal Article
Open access
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HOHIDEAKI OHASHI
HIDEAKI OHASHI
MTMayumi Tsuji
Mayumi Tsuji
TOTatsunori Oguchi
Tatsunori Oguchi
YMYutaro Momma
Yutaro Momma
TNTetsuhito Nohara
Tetsuhito Nohara
Kenjiro OnoKenjiro Ono
Kenjiro Ono
Alzheimer’s disease (AD) is a neurodegenerative disease that leads to progressive cognitive decline. Several effective natural components have been identified for the treatment of AD. However, it is difficult to obtain conclusive evidence on the safety and effectiveness of natural components, because a variety of factors are associated with the progression of AD pathology. We hypothesized that a therapeutic effect could be achieved by combining multiple ingredients with different efficacies. The purpose of this study was thus to evaluate a combination treatment of curcumin (Cur) and ferulic acid (FA) for amyloid-β (Aβ)-induced neuronal cytotoxicity. The effect of Cur or FA on Aβ aggregation using thioflavin T assay was confirmed to be inhibited in a concentration-dependent manner by Cur single or Cur + FA combination treatment. The effects of Cur + FA on the cytotoxicity of human neuroblastoma (SH-SY5Y) cells induced by Aβ exposure were an increase in cell viability, a decrease in ROS and mitochondrial ROS, and repair of membrane damage. Combination treatment showed an overall higher protective effect than treatment with Cur or FA alone. These results suggest that the combined action mechanisms of Cur and FA may be effective in preventing and suppressing the progression of AD.

20 August 2018 in Inflammation and Regeneration
Verified
Journal Article
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SYShiho Yamadera
Shiho Yamadera
YNYuya Nakamura
Yuya Nakamura
MIMasahiro Inagaki
Masahiro Inagaki
SKSachiyo Kenmotsu
Sachiyo Kenmotsu
TNTetsuhito Nohara
Tetsuhito Nohara
SIShinichi Iwai
Shinichi Iwai
Atherosclerosis and inflammation are more common in patients with diabetes than in patients without diabetes, and atherosclerosis progression contributes to inflammation. Therefore, anti-inflammatory therapy is important for the prognosis of patients with diabetes. Linagliptin is the only bile-excreted, anti-diabetic oral dipeptidyl peptidase-4 (DPP-4) inhibitor. Although the anti-inflammatory effects of DPP-4 inhibitors in vivo and in vitro have been reported, few in vitro studies have examined the effects of linagliptin using monocytes, which play a central role in arteriosclerosis-related inflammation. Herein, we assessed the anti-inflammatory effects of linagliptin in human U937 monocytes. U937 cells at densities of 1 × 106 cells/mL were cultured in Roswell Park Memorial Institute medium supplied with 10% fetal bovine serum and treated with 100 nM phorbol myristate acetate for 48 h for differentiation into macrophages. The media were replaced, and the cells were pretreated with 1, 5, 10, 50, and 100 nM linagliptin for 1 h or were left untreated. The media were then replaced again, and the cells were treated with 1 μg/mL lipopolysaccharide (LPS) or 10 nM interleukin (IL)-1β only, in combination with 1, 5, 10, 50, and 100 nM linagliptin or were left untreated. The extracted media were used to measure IL-6 and tumor necrosis factor (TNF)-α levels using enzyme-linked immunosorbent assay kits. LPS alone significantly increased IL-6 and TNF-α production compared with the control treatment. The treatment of cells with linagliptin at all concentrations significantly inhibited the LPS-stimulated IL-6 and TNF-α production. Meanwhile, IL-1β alone significantly increased IL-6 production compared with the control treatment. No significant difference in IL-6 production was noted between the cells treated with IL-1β and simultaneous treatment with IL-1β and linagliptin. Linagliptin inhibited LPS-induced inflammation in human monocytic U937 cells.

28 July 2023 in Biomedicines
Verified
Journal Article
Open access
PDF file
TNTetsuhito Nohara
Tetsuhito Nohara
MTMayumi Tsuji
Mayumi Tsuji
TOTatsunori Oguchi
Tatsunori Oguchi
YMYutaro Momma
Yutaro Momma
HOHIDEAKI OHASHI
HIDEAKI OHASHI
KYKiuchi Yuji
Kiuchi Yuji
Amyloid-β (Aβ) is one of the causes of Alzheimer’s disease (AD), damaging nerve membranes and inducing neurotoxicity. AD is more prevalent in female patients than in male patients, and women are more susceptible to developing AD due to the decline in estrogen levels around menopause. Raloxifene, a selective estrogen receptor modulator, exhibits protective effects by activating the transmembrane G-protein-coupled estrogen receptor (GPER). Additionally, raloxifene prevents mild cognitive impairment and restores cognition. However, the influence of raloxifene via GPER on highly toxic Aβ-oligomers (Aβo)-induced neurotoxicity remains uncertain. In this study, we investigated the GPER-mediated neuroprotective effects of raloxifene against the neurotoxicity caused by Aβo-induced cytotoxicity. The impact of raloxifene on Aβo-induced cell damage was evaluated using measures such as cell viability, production of reactive oxygen species (ROS) and mitochondrial ROS, peroxidation of cell-membrane phospholipids, and changes in intracellular calcium ion concentration ([Ca2+]i) levels. Raloxifene hindered Aβo-induced oxidative stress and reduced excessive [Ca2+]i, resulting in improved cell viability. Furthermore, these effects of raloxifene were inhibited with pretreatment with a GPER antagonist. Our findings suggest that raloxifene safeguards against Aβo-induced neurotoxicity by modifying oxidative parameters and maintaining [Ca2+]i homeostasis. Raloxifene may prove effective in preventing and inhibiting the progression of AD.