Title: Fat Therapeutics: The Clinical Capacity of Adipose-Derived Stem Cells and Exosomes for Human Disease and Tissue Regeneration
Authors: Shukla, L
Yuan, YN
Shayan, R
Greening, DW
Karnezis, T
Issue Year: 2020
Abstract Background: Cancer patients often require radiotherapy (RTx) to enhance their survival. Unfortunately, RTx also damages nearby healthy non-cancer tissues, leading to progressive fibrotic soft-tissue injury, consisting of pain, contracture, tissue-breakdown, infection, and lymphoedema. Mechanisms underlying the clinically observed ability of fat grafting to ameliorate some of these effects, however, are poorly understood. It was hypothesized that RTx significantly alters fibroblast cell function and the paracrine secretome of adipose-derived stem cells (ADSC) may mitigate these changes. Methods: To investigate cellular changes resulting in the fibrotic side-effects of RTx, cultured normal human dermal fibroblasts (NHDF) were irradiated (10Gy), then studied using functional assays that reflect key fibroblast functions, and compared with unirradiated controls. RNA-Seq and targeted microarrays (with specific examination of TGF beta) were performed to elucidate altered gene pathways. Finally, conditioned-media from ADSC was used to treat irradiated fibroblasts and model fat graft surgery. Results: RTx altered NHDF morphology, with cellular functional changes reflecting transition into a more invasive phenotype: increased migration, adhesion, contractility, and disordered invasion. Changes in genes regulating collagen and MMP homeostasis and cell-cycle progression were also detected. However, TGF beta was not identified as a key intracellular regulator of the fibroblast response. Finally, treatment with ADSC-conditioned media reversed the RTx-induced hypermigratory state of NHDF. Conclusions: Our findings regarding cellular and molecular changes in irradiated fibroblasts help explain clinical manifestations of debilitating RTx-induced fibrosis. ADSC-secretome-mediated reversal indicated that these constituents may be used to combat the devastating side-effects of excessive unwanted fibrosis in RTx and other human fibrotic diseases.
URI: https://publications.svi.edu.au/publications/7337
Other Identifiers 10.3389/fphar.2020.00158
Publication type Review