Funding for this research was provided by:
Japan Society for the Promotion of Science (24659185)
National Cancer Center Research and Development Fund (23-K-18, 23-A-12)
Princess Takamatsunomiya Cancer Research Fund
Received: 9 February 2017
Accepted: 27 March 2017
First Online: 31 March 2017
Compliance with ethical standards
: The authors have no conflicts of interest to disclose.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Comprehensive informed consent was obtained in the study.