Effect of Human Fat Graft on Breast Cancer Metastasis in a Murine Model
Isolated adipose stem cells have been reported to encourage migration and early metastasis of breast cancer. Mimicking a surgical situation, the authors developed a human breast cancer model to evaluate in vivo whether human adipose tissue promotes tumor growth and invasion.Methods:
Human adipose tissue was obtained from four patients. The MDA-MB-468 cell line was cultured with a lentiviral vector encoding a puromycin resistance gene and mCherry fluorescent protein. Virus-infected cells were selected. Animals were injected in the left renal capsule and divided into three experimental groups: group A, MDA-MB-468 cells (n = 4); group B, MDA-MB-468 cells/human adipose tissue (n = 4); and group C, Dulbecco’s Modified Eagle Medium/F-12 medium (negative control, n = 4). Metastatic development was monitored using an in vivo imaging system. Small breast epithelial mucin (SBEM), human hypoxanthine-guanine phosphoribosyltransferase (HPRTh), and murine hypoxanthine-guanine phosphoribosyltransferase (HPRTm) expression were analyzed by real-time polymerase chain reaction to detect multifocal metastases in right/left renal capsule, liver, spleen, and pancreas.Results:
Metastasis was observed between postinjection days 37 and 44. No significant differences were found in survival rates between groups (group A, 157 ± 42.60 days; group B, 169 ± 40.17 days). All samples expressed HPRTm. HPRTh and SBEM were expressed in left renal capsules from all group A and B mice, whereas in spleen, liver, pancreas, and right renal capsule the HPRTm and SBEM expression was not constant in all samples of group A and B mice. Differences were found between groups in HPRTh and SBEM expression but were not statistically significant.Conclusion:
Human adipose tissue used to restore breast defects after oncologic resection did not increase metastasis development risk when there were residual breast cancer cells in proximity.