1. Department of Reproductive Medicine, the First Affiliated Hospital, Xi'an Jiaotong University Medical School, Xi'an, the People's Republic of China
2. Department of Biochemistry and Molecular Biology, Xi'an Jiaotong University Medical School, Xi'an, the People's Republic of China
3. Division of Cancer Stem Cell Research, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education, Xi'an Jiaotong University Medical School, Xi'an, the People's Republic of China