Plasticity of patient-matched normal mammary epithelial cells is dependent on autologous adipose-derived stem cells.

Due to the increasing clinical application of adipose-derived stem cells (ADSC), e.g. lipotransfer for breast reconstruction, this study aimed to gain novel insights regarding ADSC influence on breast tissue remodeling and determine patient-dependent factors affecting lipotransfer as well as begin to address its oncological risks. The ADSC secretome was analyzed from five normal breast reduction patients and contained elevated levels of growth factors, cytokines and proteins mediating invasion. ADSC/ADSC secretomes were tested for their influence on the function of primary mammary epithelial cells, and tumor epithelial cells using cell culture assays. ADSC/ADSC secretomes significantly stimulated proliferation, transmigration and 3D-invasion of primary normal and tumor epithelial cells. IL-6 significantly induced an EMT and invasion. The ADSC secretome significantly upregulated normal epithelial cell gene expression including MMPs and ECM receptors. Our study supports that ADSC and its secretome promote favorable conditions for normal breast tissue remodeling by changing the microenvironment. and may also be important regarding residual breast cancer cells following surgery.

[Development of an Innovative Cell Isolation Method for the Investigation of Breast Cancer Pathogenesis and Angiogenesis for Experimental In Vitro And In Vivo Assays]. / Entwicklung eines neuen Zellisolationsverfahrens zur Erforschung der Mammakarzinompathogenese und -angiogenese für experimentelle in vitro und in vivo Assays.

Background Breast cancer is the world's most common cancer among women. Autologous lipotransfer is increasingly used for breast reconstruction following surgical removal of the tumour. In cell-assisted lipotransfer, the transplant is enriched with stem cells from adipose tissue (ADSC). Despite positive clinical results, there are some concerns regarding oncological safety due to transplanted stem cells. To date there are only a few breast cancer studies using primary cells from the same patient to enable further investigation into the complexity of cell-cell interactions in breast cancer in an experimental setting. Materials and methods We performed literature research on the topic of autologous lipotransfer. 5 different cell types (epithelial, mesenchymal cells, ADSC, endothelial cells, endothelial progenitor cells) were isolated from mammary (carcinoma) tissue or blood and were subsequently characterised for gene and protein expression as well as functional properties. The arteriovenous (AV) loop model in the rat was evaluated as a possible in vivo model for breast cancer pathogenesis and angiogenesis in this study. Results The literature provided evidence for an in-vitro interaction between ADSC and cells of the mammary (carcinoma) tissue. In some clinical studies, certain subgroups of patients appeared to be exposed to an increased risk of tumour recurrence after lipotransfer, but in most studies no correlation between lipotransfer and tumour recurrence was found. Different cell populations, which differed significantly in terms of surface markers, gene expression and functional properties, were isolated from tissue of the same patient. Axial vascularised tissue was successfully generated in the AV loop model. Conclusion In this study we were able to isolate different cell populations from the same patient, which reflect the heterogeneity of the tumour tissue. This enables a precise analysis of cell-cell interactions and their effects on tumour angiogenesis and pathogenesis in breast cancer. In combination with the AV loop model, this offers new possibilities to generate vascularised mammary carcinoma tissue as well as healthy mammary gland tissue in vivo as an optimal model for the clinical setting.

Selective isolation and characterization of primary cells from normal breast and tumors reveal plasticity of adipose derived stem cells.

BACKGROUND: There is a need to establish more cell lines from breast tumors in contrast to immortalized cell lines from metastatic effusions in order to represent the primary tumor and not principally metastatic biology of breast cancer. This investigation describes the simultaneous isolation, characterization, growth and function of primary mammary epithelial cells (MEC), mesenchymal cells (MES) and adipose derived stem cells (ADSC) from four normal breasts, one inflammatory and one triple-negative ductal breast tumors. METHODS: A total of 17 cell lines were established and gene expression was analyzed for MEC and MES (n = 42) and ADSC (n = 48) and MUC1, pan-KRT, CD90 and GATA-3 by immunofluorescence. DNA fingerprinting to track cell line identity was performed between original primary tissues and isolates. Functional studies included ADSC differentiation, tumor MES and MEC invasion co-cultured with ADSC-conditioned media (CM) and MES adhesion and growth on 3D-printed scaffolds. RESULTS: Comparative analysis showed higher gene expression of EPCAM, CD49f, CDH1 and KRTs for normal MEC lines; MES lines e.g. Vimentin, CD10, ACTA2 and MMP9; and ADSC lines e.g. CD105, CD90, CDH2 and CDH11. Compared to the mean of all four normal breast cell lines, both breast tumor cell lines demonstrated significantly lower ADSC marker gene expression, but higher expression of mesenchymal and invasion gene markers like SNAI1 and MMP2. When compared with four normal ADSC differentiated lineages, both tumor ADSC showed impaired osteogenic and chondrogenic but enhanced adipogenic differentiation and endothelial-like structures, possibly due to high PDGFRB and CD34. Addressing a functional role for overproduction of adipocytes, we initiated 3D-invasion studies including different cell types from the same patient. CM from ADSC differentiating into adipocytes induced tumor MEC 3D-invasion via EMT and amoeboid phenotypes. Normal MES breast cells adhered and proliferated on 3D-printed scaffolds containing 20 fibers, but not on 2.5D-printed scaffolds with single fiber layers, important for tissue engineering. CONCLUSION: Expression analyses confirmed successful simultaneous cell isolations of three different phenotypes from normal and tumor primary breast tissues. Our cell culture studies support that breast-tumor environment differentially regulates tumor ADSC plasticity as well as cell invasion and demonstrates applications for regenerative medicine.