TY - JOUR
T1 - CKAP4, a DKK1 receptor, is a biomarker in exosomes derived from pancreatic cancer and a molecular target for therapy
AU - Kimura, Hirokazu
AU - Yamamoto, Hideki
AU - Harada, Takeshi
AU - Fumoto, Katsumi
AU - Osugi, Yoshihito
AU - Sada, Ryota
AU - Maehara, Natsumi
AU - Hikita, Hayato
AU - Mori, Soichiro
AU - Eguchi, Hidetoshi
AU - Ikawa, Masahito
AU - Takehara, Tetsuo
AU - Kikuchi, Akira
N1 - Funding Information:
The authors thank Prof. S. Hattori for helping with statistical analyses and Cell Engineering Corporation for generating CKAP4 mAbs. The authors also thank Drs. S. Tsukita, A. Shintani, and H. Miyoshi for donating cells and plasmids, and FUJIFILM Wako Pure Chemical Corporation for providing technical advice on using MagCapture Exosome Isolation Kit PS and PS Capture Exosome ELISA Kit. This work was supported by Grants-in-Aids for Scientific Research to A. Kikuchi (2016–2020; no. 16H06374), on Innovative Area (no. JP18H04861) to A. Kikuchi, for Young Scientists (Start-up) to H. Kimura (2016–2017; no. 16H06944), and for Early-Career Scientists to H. Kimura (2018–2019; no. 18K15064) from the Ministry of Education, Culture, Sports, Science and Technology of Japan and by the Project Promoting Support for Drug Discovery (2016–2018; no. DNW-16002) to K. Fumoto and the Project for Cancer Research And Therapeutic Evolution (P-CREATE; 2016–2017; no. 16cm0106119h0001; 2018–2019; 18cm0106132h0001) to A. Kikuchi from the Japan Agency for Medical Research and development, AMED, by Integrated Frontier Research for Medical Science Division, Institute for Open and Trans-disciplinary Research Initiatives, Osaka University to A. Kikuchi, by grants from the Yasuda Memorial Foundation to A. Kikuchi and from the Osaka Community Foundation to H. Kimura.
Funding Information:
The authors thank Prof. S. Hattori for helping with statistical analyses and Cell Engineering Corporation for generating CKAP4 mAbs. The authors also thank Drs. S. Tsukita, A. Shintani, and H. Miyoshi for donating cells and plasmids, and FUJIFILM Wako Pure Chemical Corporation for providing technical advice on using MagCapture Exosome Isolation Kit PS and PS Capture Exosome ELISA Kit. This work was supported by Grants-in-Aids for Scientific Research to A. Kikuchi (2016–2020; no. 16H06374), on Innovative Area (no. JP18H04861) to A. Kikuchi, for Young Scientists (Start-up) to H. Kimura (2016– 2017; no. 16H06944), and for Early-Career Scientists to H. Kimura (2018– 2019; no. 18K15064) from the Ministry of Education, Culture, Sports, Science and Technology of Japan and by the Project Promoting Support for Drug Discovery (2016–2018; no. DNW-16002) to K. Fumoto and the Project for Cancer Research And Therapeutic Evolution (P-CREATE; 2016–2017; no. 16cm0106119h0001; 2018–2019; 18cm0106132h0001) to A. Kikuchi from the Japan Agency for Medical Research and development, AMED, by Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University to A. Kikuchi, by grants from the Yasuda Memorial Foundation to A. Kikuchi and from the Osaka Community Foundation to H. Kimura.
Publisher Copyright:
© 2019 American Association for Cancer Research.
PY - 2019
Y1 - 2019
N2 - Purpose: The survival rate of pancreatic ductal adenocarcinoma (PDAC) is poor; thus, novel molecularly targeted therapy and companion diagnostics are required. We asked whether cytoskeleton-associated protein 4 (CKAP4), a novel Dick-kopf1 (DKK1) receptor, is a candidate for PDAC diagnosis and therapy. Experimental Design: Whether CKAP4 can be secreted with small extracellular vesicles (SEV) from PDAC cells was examined. It was also investigated whether CKAP4 can be detected in sera from patients with PDAC by ELISA using newly generated anti-CKAP4 mAbs and whether anti-CKAP4 mAbs can show antitumor activity in vivo. Results: CKAP4 was secreted with SEVs from PDAC cells, and the SEVs exhibited the characteristics of exosomes. The secretion of CKAP4-containing exosomes was mediated by DKK1-dependent endocytosis routes and required exosome biogenesis molecules. Two ELISAs capable of detecting tumor-secreted CKAP4 were developed. The serum CKAP4 levels were higher in patients with PDAC than healthy control individuals. CKAP4 was highly detected in the sera of pancreatic tumor-bearing xenografted mice and patients with PDAC, whereas CKAP4 was barely detectable in sera from normal mice and postoperative patients. Anti-CKAP4 mAbs with different epitopes demonstrated the inhibitory activities for the binding of DKK1 and CKAP4, AKT activity, and proliferation and migration of PDAC cells. Anti-CKAP4 mAbs also suppressed xenograft tumor formation in immunodeficient mice and extended the survival of mice receiving intraperitoneal or orthotopic injection of PDAC cells. Conclusions: CKAP4 secreted in exosomes may represent a biomarker for PDAC. Anti-CKAP4 mAbs can contribute to the development of novel diagnostic methods and therapeutics.
AB - Purpose: The survival rate of pancreatic ductal adenocarcinoma (PDAC) is poor; thus, novel molecularly targeted therapy and companion diagnostics are required. We asked whether cytoskeleton-associated protein 4 (CKAP4), a novel Dick-kopf1 (DKK1) receptor, is a candidate for PDAC diagnosis and therapy. Experimental Design: Whether CKAP4 can be secreted with small extracellular vesicles (SEV) from PDAC cells was examined. It was also investigated whether CKAP4 can be detected in sera from patients with PDAC by ELISA using newly generated anti-CKAP4 mAbs and whether anti-CKAP4 mAbs can show antitumor activity in vivo. Results: CKAP4 was secreted with SEVs from PDAC cells, and the SEVs exhibited the characteristics of exosomes. The secretion of CKAP4-containing exosomes was mediated by DKK1-dependent endocytosis routes and required exosome biogenesis molecules. Two ELISAs capable of detecting tumor-secreted CKAP4 were developed. The serum CKAP4 levels were higher in patients with PDAC than healthy control individuals. CKAP4 was highly detected in the sera of pancreatic tumor-bearing xenografted mice and patients with PDAC, whereas CKAP4 was barely detectable in sera from normal mice and postoperative patients. Anti-CKAP4 mAbs with different epitopes demonstrated the inhibitory activities for the binding of DKK1 and CKAP4, AKT activity, and proliferation and migration of PDAC cells. Anti-CKAP4 mAbs also suppressed xenograft tumor formation in immunodeficient mice and extended the survival of mice receiving intraperitoneal or orthotopic injection of PDAC cells. Conclusions: CKAP4 secreted in exosomes may represent a biomarker for PDAC. Anti-CKAP4 mAbs can contribute to the development of novel diagnostic methods and therapeutics.
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U2 - 10.1158/1078-0432.CCR-18-2124
DO - 10.1158/1078-0432.CCR-18-2124
M3 - Article
C2 - 30610103
AN - SCOPUS:85062955440
SN - 1078-0432
VL - 25
SP - 1936
EP - 1947
JO - Clinical Cancer Research
JF - Clinical Cancer Research
IS - 6
ER -
