Masaya Sato

Dr. Masaya Sato

The University of Tokyo
orcid

Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

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

Representative Publications

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30 May 2019 in Scientific Reports
Verified
Journal Article
Open access
PDF file
MSMasaya Sato
Masaya Sato
KMKentaro Morimoto
Kentaro Morimoto
SKShigeki Kajihara
Shigeki Kajihara
RTRyosuke Tateishi
Ryosuke Tateishi
SSShuichiro Shiina
Shuichiro Shiina
YYYutaka Yatomi
Yutaka Yatomi
Because of its multifactorial nature, predicting the presence of cancer using a single biomarker is difficult. We aimed to establish a novel machine-learning model for predicting hepatocellular carcinoma (HCC) using real-world data obtained during clinical practice. To establish a predictive model, we developed a machine-learning framework which developed optimized classifiers and their respective hyperparameter, depending on the nature of the data, using a grid-search method. We applied the current framework to 539 and 1043 patients with and without HCC to develop a predictive model for the diagnosis of HCC. Using the optimal hyperparameter, gradient boosting provided the highest predictive accuracy for the presence of HCC (87.34%) and produced an area under the curve (AUC) of 0.940. Using cut-offs of 200 ng/mL for AFP, 40 mAu/mL for DCP, and 15% for AFP-L3, the accuracies of AFP, DCP, and AFP-L3 for predicting HCC were 70.67% (AUC, 0.766), 74.91% (AUC, 0.644), and 71.05% (AUC, 0.683), respectively. A novel predictive model using a machine-learning approach reduced the misclassification rate by about half compared with a single tumor marker. The framework used in the current study can be applied to various kinds of data, thus potentially become a translational mechanism between academic research and clinical practice.

1 June 2022 in Journal of Clinical Investigation
Verified
Journal Article
Open access
PDF file
SKSatoshi Kawamura
Satoshi Kawamura
YMYuki Matsushita
Yuki Matsushita
SKShigeyuki Kurosaki
Shigeyuki Kurosaki
MTMizuki Tange
Mizuki Tange
NFNaoto Fujiwara
Naoto Fujiwara
HNHayato Nakagawa
Hayato Nakagawa
Enhanced de novo lipogenesis mediated by sterol regulatory element–binding proteins (SREBPs) is thought to be involved in nonalcoholic steatohepatitis (NASH) pathogenesis. In this study, we assessed the impact of SREBP inhibition on NASH and liver cancer development in murine models. Unexpectedly, SREBP inhibition via deletion of the SREBP cleavage–activating protein (SCAP) in the liver exacerbated liver injury, fibrosis, and carcinogenesis despite markedly reduced hepatic steatosis. These phenotypes were ameliorated by restoring SREBP function. Transcriptome and lipidome analyses revealed that SCAP/SREBP pathway inhibition altered the fatty acid (FA) composition of phosphatidylcholines due to both impaired FA synthesis and disorganized FA incorporation into phosphatidylcholine via lysophosphatidylcholine acyltransferase 3 (LPCAT3) downregulation, which led to endoplasmic reticulum (ER) stress and hepatocyte injury. Supplementation with phosphatidylcholines significantly improved liver injury and ER stress induced by SCAP deletion. The activity of the SCAP/SREBP/LPCAT3 axis was found to be inversely associated with liver fibrosis severity in human NASH. SREBP inhibition also cooperated with impaired autophagy to trigger liver injury. Thus, excessively strong and broad lipogenesis inhibition was counterproductive for NASH therapy; this will have important clinical implications in NASH treatment.

1 January 2019 in Journal of Hepatology
Verified
Journal Article
Closed access
MKMizuki Nishibatake Kinoshita
Mizuki Nishibatake Kinoshita
TMTatsuya Minami
Tatsuya Minami
RTRyosuke Tateishi
Ryosuke Tateishi
TWTaijiro Wake
Taijiro Wake
RNRyo Nakagomi
Ryo Nakagomi
KKKazuhiko Koike
Kazuhiko Koike

27 February 2022 in Journal of Gastroenterology
Verified
Journal Article
Open access
PDF file
Naoshi NishidaNaoshi Nishida
Naoshi Nishida
MYMakoto Yamakawa
Makoto Yamakawa
STShiina Tsuyoshi
Shiina Tsuyoshi
YMYoshito Mekada
Yoshito Mekada
MNMutsumi Nishida
Mutsumi Nishida
JIJSUM A. I. investigators
JSUM A. I. investigators
Background: Ultrasonography (US) is widely used for the diagnosis of liver tumors. However, the accuracy of the diagnosis largely depends on the visual perception of humans. Hence, we aimed to construct artificial intelligence (AI) models for the diagnosis of liver tumors in US. Methods: We constructed three AI models based on still B-mode images: model-1 using 24,675 images, model-2 using 57,145 images, and model-3 using 70,950 images. A convolutional neural network was used to train the US images. The four-class liver tumor discrimination by AI, namely, cysts, hemangiomas, hepatocellular carcinoma, and metastatic tumors, was examined. The accuracy of the AI diagnosis was evaluated using tenfold cross-validation. The diagnostic performances of the AI models and human experts were also compared using an independent test cohort of video images. Results: The diagnostic accuracies of model-1, model-2, and model-3 in the four tumor types are 86.8%, 91.0%, and 91.1%, whereas those for malignant tumor are 91.3%, 94.3%, and 94.3%, respectively. In the independent comparison of the AIs and physicians, the percentages of correct diagnoses (accuracies) by the AIs are 80.0%, 81.8%, and 89.1% in model-1, model-2, and model-3, respectively. Meanwhile, the median percentages of correct diagnoses are 67.3% (range 63.6%–69.1%) and 47.3% (45.5%–47.3%) by human experts and non-experts, respectively. Conclusion: The performance of the AI models surpassed that of human experts in the four-class discrimination and benign and malignant discrimination of liver tumors. Thus, the AI models can help prevent human errors in US diagnosis.

20 May 2024 in Hepatology
Verified
Journal Article
Open access
TNTakuma Nakatsuka
Takuma Nakatsuka
RTRyosuke Tateishi
Ryosuke Tateishi
MSMasaya Sato
Masaya Sato
NHNatsuka Hashizume
Natsuka Hashizume
AKAmi Kamada
Ami Kamada
KKKazuhiko Koike
Kazuhiko Koike
Background and Aims: Identifying patients with steatotic liver disease who are at a high risk of developing HCC remains challenging. We present a deep learning (DL) model to predict HCC development using hematoxylin and eosin-stained whole-slide images of biopsy-proven steatotic liver disease. Approach and Results: We included 639 patients who did not develop HCC for ≥7 years after biopsy (non-HCC class) and 46 patients who developed HCC <7 years after biopsy (HCC class). Paired cases of the HCC and non-HCC classes matched by biopsy date and institution were used for training, and the remaining nonpaired cases were used for validation. The DL model was trained using deep convolutional neural networks with 28,000 image tiles cropped from whole-slide images of the paired cases, with an accuracy of 81.0% and an AUC of 0.80 for predicting HCC development. Validation using the nonpaired cases also demonstrated a good accuracy of 82.3% and an AUC of 0.84. These results were comparable to the predictive ability of logistic regression model using fibrosis stage. Notably, the DL model also detected the cases of HCC development in patients with mild fibrosis. The saliency maps generated by the DL model highlighted various pathological features associated with HCC development, including nuclear atypia, hepatocytes with a high nuclear-cytoplasmic ratio, immune cell infiltration, fibrosis, and a lack of large fat droplets. Conclusions: The ability of the DL model to capture subtle pathological features beyond fibrosis suggests its potential for identifying early signs of hepatocarcinogenesis in patients with steatotic liver disease. Export

15 September 2023 in Journal of Hepatology
Verified
Journal Article
Closed access
TMTatsuya Minami
Tatsuya Minami
MSMasaya Sato
Masaya Sato
HTHidenori Toyoda
Hidenori Toyoda
SYSatoshi Yasuda
Satoshi Yasuda
TYTomoharu Yamada
Tomoharu Yamada
RTRyosuke Tateishi
Ryosuke Tateishi