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Physical Intimacy of Breast Cancer Cells with Mesenchymal Stem Cells Elicits Trastuzumab Resistance through Src Activation.

Daverey A, Drain AP, Kidambi S - Sci Rep (2015)

Bottom Line: The development of resistance to trastuzumab is a major obstacle for lasting effective treatment of patients with ErbB2-overexpressing tumors.To our knowledge, this is the first report that showed PTEN loss without the use of chemical inhibitors, matrix stiffness, or silencing RNAs.Our findings show that MSCs are potent mediators of resistance to trastuzumab and might reveal targets to enhance trastuzumab efficacy in patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, NE, 68588.

ABSTRACT
The development of resistance to trastuzumab is a major obstacle for lasting effective treatment of patients with ErbB2-overexpressing tumors. Here, we demonstrate that the physical contact of breast cancer cells with mesenchymal stem cells (MSCs) is a potential modulator of trastuzumab response by activation of nonreceptor tyrosine kinase c-Src and down regulation of phosphatase and tensin homolog (PTEN). Using an in vitro patterned breast cancer/MSC co-culture model, we find that the presence of MSCs results in Src activation that is missing in cancer cells monoculture, transwell co-culture, and cells treated with MSCs conditioned media. Interestingly, the co-culture model also results in PTEN loss and activation of PI3K/AKT pathway that has been demonstrated as fundamental proliferative and survival pathways in clinical settings. To our knowledge, this is the first report that showed PTEN loss without the use of chemical inhibitors, matrix stiffness, or silencing RNAs. In addition, breast cancer cells in co-culture with MSCs conferred trastuzumab resistance in vitro as observed in the lack of inhibition of proliferative and migrative properties of the cancer cells. Our findings show that MSCs are potent mediators of resistance to trastuzumab and might reveal targets to enhance trastuzumab efficacy in patients.

No MeSH data available.


Related in: MedlinePlus

Establishing patterned co-culture of breast cancer cells and MSCs.(a) Left, optical micrographs of breast cancer cells and MSCs cultured on various surfaces after 5 days (Scale bar, 500 μm); Right, quantitative analysis of attachment of cells determined with MTT assay. Cells grown on TCPS were used as control. Mean ± SD; n = 3 independent experiments; **p < 0.01 compared with control. (b) Left, immunoblots show protein expression of specific markers of BT-474, 21MT-1 and MSCs on different surfaces. Right, respective densitometry of bands normalized with control after loading control (GAPDH) correction. Cells grown on TCPS served as control. (c) Scheme illustrating the approach for engineering patterned co-culture of breast cancer cells and MSCs (The scheme is not drawn to represent the true nature of the co-culture system) Fluorescent images of patterned monocultures of BT-474 and 21MT-1 (green) and patterned co-culture of breast cancer cells (green) and MSCs (red) after seeding MSCs (Scale bars- 200 μm).
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f2: Establishing patterned co-culture of breast cancer cells and MSCs.(a) Left, optical micrographs of breast cancer cells and MSCs cultured on various surfaces after 5 days (Scale bar, 500 μm); Right, quantitative analysis of attachment of cells determined with MTT assay. Cells grown on TCPS were used as control. Mean ± SD; n = 3 independent experiments; **p < 0.01 compared with control. (b) Left, immunoblots show protein expression of specific markers of BT-474, 21MT-1 and MSCs on different surfaces. Right, respective densitometry of bands normalized with control after loading control (GAPDH) correction. Cells grown on TCPS served as control. (c) Scheme illustrating the approach for engineering patterned co-culture of breast cancer cells and MSCs (The scheme is not drawn to represent the true nature of the co-culture system) Fluorescent images of patterned monocultures of BT-474 and 21MT-1 (green) and patterned co-culture of breast cancer cells (green) and MSCs (red) after seeding MSCs (Scale bars- 200 μm).

Mentions: To further investigate the effect of interaction of MSCs with breast cancer cells, we established a patterned co-culture system of breast cancer cells with MSCs using polyelectrolyte multilayer (PEM) films. We have previously screened several polymers similar to self-assemble protein network found in extracellular matrix35. Among all polymers, poly(diallyldimethylammonium chloride) (PDAC) and poly(4-styrenesulfonic acid) (SPS) were selected due to their ability to produce most consistent observations with cell attachment (Fig. 2A). For all experiments, 10 or 10.5 bilayers of PDAC/SPS were deposited on tissue culture polystyrene surfaces (TCPS) making SPS or PDAC as topmost layer and are designated as (PDAC/SPS)10 or (PDAC/SPS)10.5 respectively. No difference in morphology and growth of BT-474, 21MT-1 and MSCs were observed when cells were grown on (PDAC/SPS)10 compared to control. Quantitative analysis of attachment of cells on PEM films indicated higher attachment on (PDAC/SPS)10 compared to (PDAC/SPS)10.5 (Fig. 2A and Supplementary Fig. 2). The specific protein markers for breast cancer cells (HER-2 expression) and for MSCs (CD166) remained unchanged on both polymer surfaces compared to control, suggesting that polymer surfaces do not influence the biology of the cells beyond the cell adhesion behavior (Fig. 2B).


Physical Intimacy of Breast Cancer Cells with Mesenchymal Stem Cells Elicits Trastuzumab Resistance through Src Activation.

Daverey A, Drain AP, Kidambi S - Sci Rep (2015)

Establishing patterned co-culture of breast cancer cells and MSCs.(a) Left, optical micrographs of breast cancer cells and MSCs cultured on various surfaces after 5 days (Scale bar, 500 μm); Right, quantitative analysis of attachment of cells determined with MTT assay. Cells grown on TCPS were used as control. Mean ± SD; n = 3 independent experiments; **p < 0.01 compared with control. (b) Left, immunoblots show protein expression of specific markers of BT-474, 21MT-1 and MSCs on different surfaces. Right, respective densitometry of bands normalized with control after loading control (GAPDH) correction. Cells grown on TCPS served as control. (c) Scheme illustrating the approach for engineering patterned co-culture of breast cancer cells and MSCs (The scheme is not drawn to represent the true nature of the co-culture system) Fluorescent images of patterned monocultures of BT-474 and 21MT-1 (green) and patterned co-culture of breast cancer cells (green) and MSCs (red) after seeding MSCs (Scale bars- 200 μm).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4561910&req=5

f2: Establishing patterned co-culture of breast cancer cells and MSCs.(a) Left, optical micrographs of breast cancer cells and MSCs cultured on various surfaces after 5 days (Scale bar, 500 μm); Right, quantitative analysis of attachment of cells determined with MTT assay. Cells grown on TCPS were used as control. Mean ± SD; n = 3 independent experiments; **p < 0.01 compared with control. (b) Left, immunoblots show protein expression of specific markers of BT-474, 21MT-1 and MSCs on different surfaces. Right, respective densitometry of bands normalized with control after loading control (GAPDH) correction. Cells grown on TCPS served as control. (c) Scheme illustrating the approach for engineering patterned co-culture of breast cancer cells and MSCs (The scheme is not drawn to represent the true nature of the co-culture system) Fluorescent images of patterned monocultures of BT-474 and 21MT-1 (green) and patterned co-culture of breast cancer cells (green) and MSCs (red) after seeding MSCs (Scale bars- 200 μm).
Mentions: To further investigate the effect of interaction of MSCs with breast cancer cells, we established a patterned co-culture system of breast cancer cells with MSCs using polyelectrolyte multilayer (PEM) films. We have previously screened several polymers similar to self-assemble protein network found in extracellular matrix35. Among all polymers, poly(diallyldimethylammonium chloride) (PDAC) and poly(4-styrenesulfonic acid) (SPS) were selected due to their ability to produce most consistent observations with cell attachment (Fig. 2A). For all experiments, 10 or 10.5 bilayers of PDAC/SPS were deposited on tissue culture polystyrene surfaces (TCPS) making SPS or PDAC as topmost layer and are designated as (PDAC/SPS)10 or (PDAC/SPS)10.5 respectively. No difference in morphology and growth of BT-474, 21MT-1 and MSCs were observed when cells were grown on (PDAC/SPS)10 compared to control. Quantitative analysis of attachment of cells on PEM films indicated higher attachment on (PDAC/SPS)10 compared to (PDAC/SPS)10.5 (Fig. 2A and Supplementary Fig. 2). The specific protein markers for breast cancer cells (HER-2 expression) and for MSCs (CD166) remained unchanged on both polymer surfaces compared to control, suggesting that polymer surfaces do not influence the biology of the cells beyond the cell adhesion behavior (Fig. 2B).

Bottom Line: The development of resistance to trastuzumab is a major obstacle for lasting effective treatment of patients with ErbB2-overexpressing tumors.To our knowledge, this is the first report that showed PTEN loss without the use of chemical inhibitors, matrix stiffness, or silencing RNAs.Our findings show that MSCs are potent mediators of resistance to trastuzumab and might reveal targets to enhance trastuzumab efficacy in patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, NE, 68588.

ABSTRACT
The development of resistance to trastuzumab is a major obstacle for lasting effective treatment of patients with ErbB2-overexpressing tumors. Here, we demonstrate that the physical contact of breast cancer cells with mesenchymal stem cells (MSCs) is a potential modulator of trastuzumab response by activation of nonreceptor tyrosine kinase c-Src and down regulation of phosphatase and tensin homolog (PTEN). Using an in vitro patterned breast cancer/MSC co-culture model, we find that the presence of MSCs results in Src activation that is missing in cancer cells monoculture, transwell co-culture, and cells treated with MSCs conditioned media. Interestingly, the co-culture model also results in PTEN loss and activation of PI3K/AKT pathway that has been demonstrated as fundamental proliferative and survival pathways in clinical settings. To our knowledge, this is the first report that showed PTEN loss without the use of chemical inhibitors, matrix stiffness, or silencing RNAs. In addition, breast cancer cells in co-culture with MSCs conferred trastuzumab resistance in vitro as observed in the lack of inhibition of proliferative and migrative properties of the cancer cells. Our findings show that MSCs are potent mediators of resistance to trastuzumab and might reveal targets to enhance trastuzumab efficacy in patients.

No MeSH data available.


Related in: MedlinePlus