Purpose: Autologous transplantation of adipose tissue into the breast is commonly performed in clinical practice, but its oncological safety has not been established.
Methods: We conducted an in vitro study to assess the influence of factors released by adipose-derived stem cells (ASCs), from multiple source tissues and harvested using different techniques, on proliferation and invasiveness of two breast cancer cell lines.
Results: Fat specimens of 66 donors (57 female, 9 male) were collected and 44 ASC cultures were established. ASC conditioning of the medium (CM) increased the proliferation of MCF-7 cells (178.4 ± 62.8%; P < 0.001), whereas MDA-MB321 proliferation was decreased (87.3 ± 15.3%; P = 0.032). We observed increased cell migration (174.0 ± 62.8%; P = 0.002), but not cell invasion (1.28 ± 0.51; P = 0.14) in MDA-MB231. Migration and invasion of MCF-7 cells were not affected by exposure to ASC-CM. For MCF-7 cell migration, lower BMI (< 25 kg/m2) was associated with increased migration, both in univariate (P = 0.015) and multivariate (P = 0.039) analyses. Regarding the cytokine secretome, proliferation of MCF-7 was positively correlated with levels of eotaxin 1 and insulin-like growth factor-binding protein 3 in the CM, and inversely correlated with levels of interleukin 1β and transforming growth factor β-3. In case of MDA-MB231, granulocyte colony-stimulating factor, angiogenin, eotaxin 1 and 3, neutrophil activating peptide 2, and neurotrophin-3 were positively correlated with proliferation.
Conclusions: We conclude that fat tissue transplantation increases proliferation and migration, but not invasion, of breast cancer cells. These findings are consistent with clinical data regarding the safety of autologous fat transplantation in breast cancer patients.
Keywords: Autologous fat transfer; Breast cancer cell lines; Invasion; Preadipocytes; Proliferation.