Takehito Yamamoto

Dr. Takehito Yamamoto

orcid

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

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

Representative Publications

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Verified
Journal Article
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TYTakehito Yamamoto
Takehito Yamamoto
KKKenji Kawada
Kenji Kawada
KOKazutaka Obama
Kazutaka Obama
Colorectal cancer (CRC) is the leading cause of cancer deaths around the world. It is necessary to identify patients with poor prognosis or with high risk for recurrence so that we can selectively perform intensive treatments such as preoperative and/or postoperative chemotherapy and extended surgery. The clinical usefulness of inflammation-related prognostic biomarkers available from routine blood examination has been reported in many types of cancer, e.g., neutrophil–lymphocyte ratio (NLR), lymphocyte–C-reactive protein ratio (LCR), platelet–lymphocyte ratio (PLR), lymphocyte–monocyte ratio (LMR), and so on. Moreover, some scoring systems based on circulating blood cell counts and albumin concentration have been also reported to predict cancer patients’ prognosis, such as the Glasgow prognostic score (GPS), systemic inflammation score (SIS), and prognostic nutritional index (PNI). The optimal biomarker and optimal cutoff value of the markers can be different depending on the cancer type. In this review, we summarize the prognostic impact of each inflammation-related marker in CRC.

5 February 2019 in International Journal of Clinical Oncology
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Journal Article
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TYTakehito Yamamoto
Takehito Yamamoto
KKKenji Kawada
Kenji Kawada
KHKoy Hid
Koy Hid
RGRiki Ganeko
Riki Ganeko
SISusumu Inamoto
Susumu Inamoto
YSYoshiharu Sakai
Yoshiharu Sakai

22 July 2020 in Cancers
Verified
Journal Article
Open access
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TYTakehito Yamamoto
Takehito Yamamoto
HMHiroyuki Miyoshi
Hiroyuki Miyoshi
Fumihiko KakizakiFumihiko Kakizaki
Fumihiko Kakizaki
HMHisatsugu Maekawa
Hisatsugu Maekawa
TYTadayoshi Yamaura
Tadayoshi Yamaura
Makoto Mark TaketoMakoto Mark Taketo
Makoto Mark Taketo
Some colorectal cancer patients harboring FGFR (fibroblast growth factor receptor) genetic alterations, such as copy number gain, mutation, and/or mRNA overexpression, were selected for enrollment in several recent clinical trials of FGFR inhibitor, because these genetic alterations were preclinically reported to be associated with FGFR inhibitor sensitivity as well as poor prognosis, invasiveness, and/or metastatic potential. However, few enrolled patients were responsive to FGFR inhibitors. Thus, practical strategies are eagerly awaited that can stratify patients for the subset that potentially responds to FGFR inhibitor chemotherapy. In the present study, we evaluated the sensitivity to FGFR inhibitor erdafitinib on 25 patient-derived tumor-initiating cell (TIC) spheroid lines carrying wild-type RAS and RAF genes, both in vitro and in vivo. Then, we assessed possible correlations between the sensitivity and the genetic/genomic data of the spheroid lines tested. Upon their exposure to erdafitinib, seven lines (7/25, 28%) responded significantly. Normal colonic epithelial stem cells were unaffected by the inhibitors. Moreover, the combination of erdafitinib with EGFR inhibitor erlotinib showed stronger growth inhibition than either drug alone, as efficacy was observed in 21 lines (84%) including 14 (56%) that were insensitive to erdafitinib alone. The in vitro erdafitinib response was accurately reflected on mouse xenografts of TIC spheroid lines. However, we found little correlation between their genetic/genomic alterations of TIC spheroids and the sensitivity to the FGFR inhibitor. Accordingly, we propose that direct testing of the patient-derived spheroids in vitro is one of the most reliable personalized methods in FGFR-inhibitor therapy of colorectal cancer patients.

9 July 2024 in Surgery Today
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Journal Article
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TYTakehito Yamamoto
Takehito Yamamoto
KGKentaro Goto
Kentaro Goto
SKShoichi Kitano
Shoichi Kitano
YMYurina Maeshima
Yurina Maeshima
TYToshiyuki Yamada
Toshiyuki Yamada
TTTatsuro Tajiri
Tatsuro Tajiri
The purpose of our narrative review is to summarize the utilization of social media (SoMe) platforms for research communication within the field of surgery. We searched the PubMed database for articles in the last decade that discuss the utilization of SoMe in surgery and then categorized the diverse purposes of SoMe. SoMe proved to be a powerful tool for disseminating articles. Employing strategic methods like visual abstracts enhances article citation rates, the impact factor, h-index, and Altmetric score (an emerging alternative metric that comprehensively and instantly quantifies the social impact of scientific papers). SoMe also proved valuable for surgical education, with online videos shared widely for surgical training. However, it is essential to acknowledge the associated risk of inconsistency in quality. Moreover, SoMe facilitates discussion on specific topics through hashtags or closed groups and is instrumental in recruiting surgeons, with over half of general surgery residency programs in the US efficiently leveraging these platforms to attract the attention of potential candidates. Thus, there is a wealth of evidence supporting the effective use of SoMe for surgeons. In the contemporary era where SoMe is widely utilized, surgeons should be well-versed in this evidence.

12 April 2023 in Frontiers in Surgery
Verified
Journal Article
Open access
TYTakehito Yamamoto
Takehito Yamamoto
MYMami Yoshitomi
Mami Yoshitomi
YOYoshiki Oshimo
Yoshiki Oshimo
YNYuta Nishikawa
Yuta Nishikawa
KHKoji Hisano
Koji Hisano
HTHiroaki Terajima
Hiroaki Terajima
Background: Surgical site infection (SSI) is one of the most important complications of surgery for gastroenterological malignancies because it leads to a prolonged postoperative hospital stay and increased inpatient costs. Furthermore, SSI can delay the initiation of postoperative treatments, including adjuvant chemotherapy, negatively affecting patient prognosis. Identifying the risk factors for SSI is important to improving intra- and postoperative wound management for at-risk patients.Methods: Patients with gastroenterological malignancies who underwent surgery at our institution were retrospectively reviewed and categorized according to the presence or absence of incisional SSI. Clinicopathological characteristics such as age, sex, body mass index, malignancy location, postoperative blood examination results, operation time, and blood loss volume were compared between groups. The same analysis was repeated of only patients with colorectal malignancies.Results: A total of 528 patients (330 men, 198 women; mean age, 68 ± 11 years at surgery) were enrolled. The number of patients with diseases of the esophagus, stomach, small intestine, colon and rectum, liver, gallbladder, and pancreas were 25, 150, seven, 255, 51, five, and 35, respectively. Open surgery was performed in 303 patients vs. laparoscopic surgery in 225 patients. An incisional SSI occurred in 46 patients (8.7%). Multivariate logistic regression analysis showed that postoperative hyperglycemia (serum glucose level ≥140 mg/dl within 24 h after surgery), colorectal malignancy, and open surgery were independent risk factors for incisional SSI. In a subgroup analysis of patients with colorectal malignancy, incisional SSI occurred in 27 (11%) patients. Open surgery was significantly correlated with the occurrence of incisional SSI (P = 0.024).Conclusions: Postoperative hyperglycemia and open surgery were significant risk factors for SSI in patients with gastroenterological malignancies. Minimally invasive surgery could reduce the occurrence of incisional SSI.

10 February 2023 in Molecular Cancer Therapeutics
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Journal Article
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HMHiroyuki Matsubara
Hiroyuki Matsubara
HMHiroyuki Miyoshi
Hiroyuki Miyoshi
Fumihiko KakizakiFumihiko Kakizaki
Fumihiko Kakizaki
TMTomonori Morimoto
Tomonori Morimoto
KKKenji Kawada
Kenji Kawada
Makoto Mark TaketoMakoto Mark Taketo
Makoto Mark Taketo
Recent advances in combinatorial chemistry led to the discovery of inhibitors targeting the KRAS G12C-mutant protein. However, efficacy of its monotherapy on colorectal cancer is limited. Thus, effective combination drugs should be explored for applicable patients with colorectal cancer to fully benefit from the KRAS G12C inhibitor treatment. Here we used a patient-derived colorectal cancer stem cell (PD–CRC-SC) spheroid culture and showed that three-drug combination of inhibitors against KRAS G12C, EGFR, and FGFR synergistically suppressed the growth of colorectal cancer cells carrying the KRAS G12C mutation. Likewise, a combination of KRAS G12C and SHP2 inhibitors was also effective. Importantly, activation of the PI3K/AKT pathway in heregulin-responsive colorectal cancer cells canceled out the effect of KRAS G12C inhibition, which was largely overcome by PI3K inhibitors. These results reveal that evaluating efficacy of combination therapies with PD–CRC-SC spheroids can be a promising strategy to find the best regimen for patients with colorectal cancer.