Funding for this research was provided by:
National Natural Science Foundation of China (31770876, 81470441)
Received: 24 January 2019
Accepted: 7 May 2019
First Online: 22 May 2019
Ethics approval and consent to participate
: This study was approved by local ethics committees (Shantou University Medical College, China, Permission number: SUMC-2015-42) and patients provided written informed consent for tissue storage and analysis.
: Not applicable.
: The authors declare that they have no competing interests.
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