Funding for this research was provided by:
Beijing Hope Run Special Fund of Cancer Foundation of China ((LC2016L04)))
Received: 18 June 2020
Accepted: 18 August 2020
First Online: 14 September 2020
Ethics approval and consent to participate
: The study protocol has been approved by the ethics committee of the Chinese Academy of Medical Sciences (18–175/1753). Written informed consent will be obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.