title: An Evaluation of the Stemness, Paracrine, and Tumorigenic Characteristics of Highly Expanded, Minimally Passaged Adipose-Derived Stem Cells.
abstract: The use of adipose-derived stem cells (ADSC) in regenerative medicine is rising due to their plasticity, capacity of differentiation and paracrine and trophic effects. Despite the large number of cells obtained from adipose tissue, it is usually not enough for therapeutic purposes for many diseases or cosmetic procedures. Thus, there is the need for culturing and expanding cells in-vitro for several weeks remain. Our aim is to investigate if long- term proliferation with minimal passaging will affect the stemness, paracrine secretions and carcinogenesis markers of ADSC. The immunophenotypic properties and aldehyde dehydrogenase (ALDH) activity of the initial stromal vascular fraction (SVF) and serially passaged ADSC were observed by flow cytometry. In parallel, the telomerase activity and the relative expression of oncogenes and tumor suppressor genes were assessed by q-PCR. We also assessed the cytokine secretion profile of passaged ADSC by an ELISA. The expanded ADSC retain their morphological and phenotypical characteristics. These cells maintained in culture for up to 12 weeks until P4, possessed stable telomerase and ALDH activity, without having a TP53 mutation. Furthermore, the relative expression levels of TP53, RB, and MDM2 were not affected while the relative expression of c-Myc decreased significantly. Finally, the levels of the secretions of PGE2, STC1, and TIMP2 were not affected but the levels of IL-6, VEGF, and TIMP 1 significantly decreased at P2. Our results suggest that the expansion of passaged ADSC does not affect the differentiation capacity of stem cells and does not confer a cancerous state or capacity in vitro to the cells.
authors.affiliation: Regenerative Medicine and Inflammation Laboratory, Faculty of Medicine, St. Joseph University, Beirut, Lebanon.
authors.forename: Oula
authors.initials: O
authors.lastname: El Atat
authors.affiliation: Toxicology Laboratory, Faculty of Pharmacy, St. Joseph University, Beirut, Lebanon.
authors.forename: Diane
authors.initials: D
authors.lastname: Antonios
authors.affiliation: Cancer and Metabolism Laboratory, Faculty of Medicine, St. Joseph University, Beirut, Lebanon.
authors.forename: George
authors.initials: G
authors.lastname: Hilal
authors.affiliation: Department of Plastic& Reconstructive Surgery, Hotel Dieu de France, and Faculty of Medicine St Joseph University, Beirut, Lebanon.
authors.forename: Nabil
authors.initials: N
authors.lastname: Hokayem
authors.affiliation: Medical Genetics Unit, Faculty of Medicine, St. Joseph University, Beirut, Lebanon.
authors.forename: Joelle
authors.initials: J
authors.lastname: Abou-Ghoch
authors.affiliation: Department of Plastic& Reconstructive Surgery, Fuad Khoury Hospital, Beirut, Lebanon.
authors.forename: Hussein
authors.initials: H
authors.lastname: Hashim
authors.affiliation: Regenerative Medicine and Inflammation Laboratory, Faculty of Medicine, St. Joseph University, Beirut, Lebanon.
authors.forename: Rim
authors.initials: R
authors.lastname: Serhal
authors.affiliation: Regenerative Medicine and Inflammation Laboratory, Faculty of Medicine, St. Joseph University, Beirut, Lebanon.
authors.forename: Clara
authors.initials: C
authors.lastname: Hebbo
authors.affiliation: Regenerative Medicine and Inflammation Laboratory, Faculty of Medicine, St. Joseph University, Beirut, Lebanon.
authors.forename: Mayssam
authors.initials: M
authors.lastname: Moussa
authors.affiliation: Regenerative Medicine and Inflammation Laboratory, Faculty of Medicine, St. Joseph University, Beirut, Lebanon.
authors.forename: Nada
authors.initials: N
authors.lastname: Alaaeddine
mesh_terms: D000273:Adipose Tissue / Q000166:cytology* / Q000276:immunology; D000293:Adolescent; D000328:Adult; D000444:Aldehyde Dehydrogenase / Q000378:metabolism; D002454:Cell Differentiation; D019070:Cell Lineage; D006801:Humans; D016130:Immunophenotyping; D008875:Middle Aged; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology; D019098:Telomerase / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D055815:Young Adult
chemical_list: D016159:Tumor Suppressor Protein p53; D000444:Aldehyde Dehydrogenase; D019098:Telomerase