The Tyrosine Kinase Inhibitor Dasatinib Induces a Marked Adipogenic Differentiation of Human Multipotent Mesenchymal Stromal Cells

Abstract

BackgroundThe introduction of specific BCR-ABL inhibitors in chronic myelogenous leukemia therapy has entirely mutated the prognosis of this hematologic cancer from being a fatal disorder to becoming a chronic disease. Due to the probable long lasting treatment with tyrosine-kinase inhibitors (TKIs), the knowledge of their effects on normal cells is of pivotal importance.Design and MethodsWe investigated the effects of dasatinib treatment on human bone marrow-derived mesenchymal stromal cells (MSCs).ResultsOur findings demonstrate, for the first time, that dasatinib induces MSCs adipocytic differentiation. Particularly, when the TKI is added to the medium inducing osteogenic differentiation, a high MSCs percentage acquires adipocytic morphology and overexpresses adipocytic specific genes, including PPARγ, CEBPα, LPL and SREBP1c. Dasatinib also inhibits the activity of alkaline phosphatase, an osteogenic marker, and remarkably reduces matrix mineralization. The increase of PPARγ is also confirmed at protein level. The component of osteogenic medium required for dasatinib-induced adipogenesis is dexamethasone. Intriguingly, the increase of adipocytic markers is also observed in MSCs treated with dasatinib alone. The TKI effect is phenotype-specific, since fibroblasts do not undergo adipocytic differentiation or PPARγ increase.ConclusionsOur data demonstrate that dasatinib treatment affects bone marrow MSCs commitment and suggest that TKIs therapy might modify normal phenotypes with potential significant negative consequences.

Effects of tyrosine kinase inhibition on bone metabolism: untargeted consequences of targeted therapies

“…In a rat model of physiologic bone turnover, it has been shown to increase trabecular bone volume likely via inhibition of osteoclast activity, while not having a significant effect on osteoblast parameters, suggesting that dasatinib may 'dysregulate' bone remodeling (Vandyke et al 2010b). Another study has demonstrated direct MSC adipocyte differentiation at the expense of the osteoblast lineage (Borriello et al 2011). This finding raises the potential for dasatinib to contribute to skeletal fragility as has been demonstrated with another class of drug, thiazolidinediones, that preferentially direct osteoblast differentiation toward adipocytes and increase fracture risk (Bilik et al 2010).…”

Early-onset central diabetes insipidus is associated with de novo arginine vasopressin–neurophysin II or Wolfram syndrome 1 gene mutations

“…Primary cultures of fibroblasts were established as reported previously (8). Particularly, fibroblasts were obtained from: i) healthy subjects; ii) the patient identified in this study and his parents; and iii) two additional patients with Wolfram syndrome previously characterized in our departments.…”

“…Cells were collected and resuspended in lysis buffer containing 1% deoxycolate, 1% Triton X-100, 0.1% SDS, 150 mM NaCl, and protease inhibitors (8,9), and incubated for 1 h at 4 8C. Samples were, then, centrifuged and the supernatants processed by immunoblotting in order to evaluate PARP cleavage.…”

“…After incubation for 1 h at 4 8C, the supernatant was recovered and employed for the detection of wolframin by immunoblotting. A detailed description of the immunoblotting method is reported in references (8,9).…”

“…In order to confirm the specificity of the antibodies employed to assess wolframin protein expression, EPN cells were used to generate a reliable positive experimental control, i.e., EPN cells were transiently transfected with pcDNA3-Flag-HA-WFS1 plasmid encoding human wolframin using Lipofectamine 2000 (8). EPN cells were grown until they reached w60% confluence in culture medium without antibiotics and collected after 48 h of transfection.…”