Koichi Takayama

Koichi Takayama

orcid

Research Focus & Metrics

Academic Career Length

37Years (1990-Present)

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

Representative Publications

View All Publications
1 May 2017 in The Lancet Oncology
Verified
Journal Article
Closed access
TTToshiaki Takahashi
Toshiaki Takahashi
TYTakeharu Yamanaka
Takeharu Yamanaka
TSTakashi Seto
Takashi Seto
HHHideyuki Harada
Hideyuki Harada
HNHiroshi Nokihara
Hiroshi Nokihara
NYNobuyuki Yamamoto
Nobuyuki Yamamoto

31 August 2015 in Clinical Cancer Research
Verified
Journal Article
Open access
PDF file
KOKeiichi Ota
Keiichi Ota
KAKoichi Azuma
Koichi Azuma
AKAkihiko Kawahara
Akihiko Kawahara
SHSatoshi Hattori
Satoshi Hattori
EIEiji Iwama
Eiji Iwama
IOIsamu Okamoto
Isamu Okamoto
Purpose: Therapies targeted to the immune checkpoint mediated by PD-1 and PD-L1 show antitumor activity in a subset of patients with non–small cell lung cancer (NSCLC). We have now examined PD-L1 expression and its regulation in NSCLC positive for the EML4–ALK fusion gene. Experimental Design: The expression of PD-L1 at the protein and mRNA levels in NSCLC cell lines was examined by flow cytometry and by reverse transcription and real-time PCR analysis, respectively. The expression of PD-L1 in 134 surgically resected NSCLC specimens was evaluated by immunohistochemical analysis. Results: The PD-L1 expression level was higher in NSCLC cell lines positive for EML4–ALK than in those negative for the fusion gene. Forced expression of EML4–ALK in Ba/F3 cells markedly increased PD-L1 expression, whereas endogenous PD-L1 expression in EML4–ALK–positive NSCLC cells was attenuated by treatment with the specific ALK inhibitor alectinib or by RNAi with ALK siRNAs. Furthermore, expression of PD-L1 was downregulated by inhibitors of the MEK–ERK and PI3K–AKT signaling pathways in NSCLC cells positive for either EML4–ALK or activating mutations of the EGFR. Finally, the expression level of PD-L1 was positively associated with the presence of EML4–ALK in NSCLC specimens. Conclusions: Our findings that both EML4–ALK and mutant EGFR upregulate PD-L1 by activating PI3K–AKT and MEK–ERK signaling pathways in NSCLC reveal a direct link between oncogenic drivers and PD-L1 expression. Clin Cancer Res; 21(17); 4014–21. ©2015 AACR.

16 January 2019 in Nature Communications
Verified
Journal Article
Open access
PDF file
HTHirokazu Taniguchi
Hirokazu Taniguchi
TYTadaaki Yamada
Tadaaki Yamada
RWRong Wang
Rong Wang
KTKeiko Tanimura
Keiko Tanimura
YAYuta Adachi
Yuta Adachi
SYSeiji Yano
Seiji Yano
A novel EGFR-tyrosine kinase inhibitor (TKI), osimertinib, has marked efficacy in patients with EGFR-mutated lung cancer. However, some patients show intrinsic resistance and an insufficient response to osimertinib. This study showed that osimertinib stimulated AXL by inhibiting a negative feedback loop. Activated AXL was associated with EGFR and HER3 in maintaining cell survival and inducing the emergence of cells tolerant to osimertinib. AXL inhibition reduced the viability of EGFR-mutated lung cancer cells overexpressing AXL that were exposed to osimertinib. The addition of an AXL inhibitor during either the initial or tolerant phases reduced tumor size and delayed tumor re-growth compared to osimertinib alone. AXL was highly expressed in clinical specimens of EGFR-mutated lung cancers and its high expression was associated with a low response rate to EGFR-TKI. These results indicated pivotal roles for AXL and its inhibition in the intrinsic resistance to osimertinib and the emergence of osimertinib-tolerant cells.

4 December 2017 in Cancer
Verified
Journal Article
Open access
PDF file
NKNobuyuki Katakami
Nobuyuki Katakami
JUJunji Uchino
Junji Uchino
TYTakuma Yokoyama
Takuma Yokoyama
Tateaki NaitoTateaki Naito
Tateaki Naito
MKMasashi Kondo
Masashi Kondo
KEKenji Eguchi
Kenji Eguchi
BACKGROUND: Cachexia, described as weight loss (mainly in lean body mass [LBM]) and anorexia, is common in patients with advanced cancer. This study examined the efficacy and safety of anamorelin (ONO‐7643), a novel selective ghrelin receptor agonist, in Japanese cancer patients with cachexia.METHODS: This double‐blind clinical trial (ONO‐7643‐04) enrolled 174 patients with unresectable stage III/IV non–small cell lung cancer (NSCLC) and cachexia in Japan. Patients were randomized to daily oral anamorelin (100 mg) or a placebo for 12 weeks. The primary endpoint was the change from the baseline LBM (measured with dual‐energy x‐ray absorptiometry) over 12 weeks. The secondary endpoints were changes in appetite, body weight, quality of life, handgrip strength (HGS), and 6‐minute walk test (6MWT) results.RESULTS: The least squares mean change (plus or minus the standard error) in LBM from the baseline over 12 weeks was 1.38 ± 0.18 and −0.17 ± 0.17 kg in the anamorelin and placebo groups, respectively (P < .0001). Changes from the baseline in LBM, body weight, and anorexia symptoms showed significant differences between the 2 treatment groups at all time points. Anamorelin increased prealbumin at weeks 3 and 9. No changes in HGS or 6MWT were detected between the groups. Twelve weeks' treatment with anamorelin was safe and well tolerated in NSCLC patients.CONCLUSIONS: Anamorelin significantly increased LBM and improved anorexia symptoms and the nutritional state, but not motor function, in Japanese patients with advanced NSCLC. Because no effective treatment for cancer cachexia is currently available, anamorelin can be a beneficial treatment option. Cancer 2018;124:606‐16. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made.

1 April 2013 in Lung Cancer
Verified
Journal Article
Closed access
KOKyoko Okamura
Kyoko Okamura
KTKoichi Takayama
Koichi Takayama
MIMiiru Izumi
Miiru Izumi
THTaishi Harada
Taishi Harada
KFKazuto Furuyama
Kazuto Furuyama
YNYoichi Nakanishi
Yoichi Nakanishi

14 May 2012 in Cancer Research
Verified
Journal Article
Open access
PDF file
SMShohei Miyamoto
Shohei Miyamoto
HIHiroyuki Inoue
Hiroyuki Inoue
TNTakafumi Nakamura
Takafumi Nakamura
MYMeiko Yamada
Meiko Yamada
CSChika Sakamoto
Chika Sakamoto
KTKenzaburo Tani
Kenzaburo Tani
Although oncolytic virotherapy is a promising anticancer therapy, antitumor efficacy is hampered by low tumor selectivity. To identify a potent and selective oncolytic virotherapy, we carried out large-scale two-step screening of 28 enteroviral strains and found that coxsackievirus B3 (CVB3) possessed specific oncolytic activity against nine human non–small cell lung cancer (NSCLC) cell lines. CVB3-mediated cytotoxicity was positively correlated with the expression of the viral receptors, coxsackievirus and adenovirus receptor, and decay-accelerating factor, on NSCLC cells. In vitro assays revealed that the CVB3 induced apoptosis and phosphoinositide 3-kinase/Akt and mitogen-activated protein (MAP)/extracellular signal-regulated (ERK) kinase (MEK) survival signaling pathways, leading to cytotoxicity and regulation of CVB3 replication. Intratumoral injections of CVB3 elicited remarkable regression of preestablished NSCLC tumors in vivo. Furthermore, administrations of CVB3 into xenografts on the right flank resulted in significantly durable regression of uninjected xenografts on the left flank, where replication-competent CVB3 was detected. All treatments with CVB3 were well tolerated without treatment-related deaths. In addition, after CVB3 infection, NSCLC cells expressed abundant cell surface calreticulin and secreted ATP as well as translocated extranuclear high-mobility group box 1, which are required for immunogenic cell death. Moreover, intratumoral CVB3 administration markedly recruited natural killer cells and granulocytes, both of which contributed to the antitumor effects as shown by depletion assays, macrophages, and mature dendritic cells into tumor tissues. Together, our findings suggest that CVB3 is a potent and well-tolerated oncolytic agent with immunostimulatory properties active against both localized and metastatic NSCLC. Cancer Res; 72(10); 2609–21. ©2012 AACR.