title: Assessment of tumourigenic potential in long-term cryopreserved human adipose-derived stem cells.
abstract: Cryopreservation represents an efficient way to preserve human mesenchymal stem cells (hMSCs) at early culture/passage, and allows pooling of cells to achieve sufficient cells required for off-the-shelf use in clinical applications, e.g. cell-based therapies and regenerative medicine. To fully apply cryopreserved hMSCs in a clinical setting, it is necessary to evaluate their biosafety, e.g. chromosomal abnormality and tumourigenic potential. To date, many studies have demonstrated that cryopreserved hMSCs display no chromosomal abnormalities. However, the tumourigenic potential of cryopreserved hMSCs has not yet been evaluated. In the present study, we cryopreserved human adipose-derived mesenchymal stem cells (hASCs) for 3 months, using a slow freezing method with various cryoprotective agents (CPAs), followed by assessment of the tumourigenic potential of the cryopreserved hASCs after thawing and subculture. We found that long-term cryopreserved hASCs maintained normal levels of the tumour suppressor markers p53, p21, p16 and pRb, hTERT, telomerase activity and telomere length. Further, we did not observe significant DNA damage or signs of p53 mutation in cryopreserved hASCs. Our findings suggest that long-term cryopreserved hASCs are at low risk of tumourigenesis. These findings aid in establishing the biosafety profile of cryopreserved hASCs, and thus establishing low hazardous risk perception with the use of long-term cryopreserved hASCs for future clinical applications. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia.|Bioinspired Engineering and Biomechanics Centre (BEBC), Xi'an Jiaotong University, People's Republic of China.
authors.forename: Kar Wey
authors.initials: KW
authors.lastname: Yong
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Wan Kamarul Zaman Wan
authors.initials: WKZW
authors.lastname: Safwani
authors.affiliation: Bioinspired Engineering and Biomechanics Centre (BEBC), Xi'an Jiaotong University, People's Republic of China.|Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Xu
authors.affiliation: Bioinspired Engineering and Biomechanics Centre (BEBC), Xi'an Jiaotong University, People's Republic of China.|Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, People's Republic of China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia.|Bioinspired Engineering and Biomechanics Centre (BEBC), Xi'an Jiaotong University, People's Republic of China.
authors.forename: Jane Ru
authors.initials: JR
authors.lastname: Choi
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Wan Abu Bakar Wan
authors.initials: WABW
authors.lastname: Abas
authors.affiliation: Department of Obstetrics and Gynaecology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Siti Zawiah
authors.initials: SZ
authors.lastname: Omar
authors.affiliation: Department of Obstetrics and Gynaecology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mat Adenan Noor
authors.initials: MAN
authors.lastname: Azmi
authors.affiliation: Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
authors.forename: Kien Hui
authors.initials: KH
authors.lastname: Chua
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Belinda
authors.initials: B
authors.lastname: Pingguan-Murphy
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism* / Q000473:pathology; D002471:Cell Transformation, Neoplastic; D015925:Cryopreservation; D004249:DNA Damage; D005260:Female; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000378:metabolism* / Q000473:pathology; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D013997:Time Factors
chemical_list: D009363:Neoplasm Proteins
keywords: biosafety; clinical applications; human adipose-derived stem cells; long-term cryopreservation; low risk; tumourigenic potential assessment