Objective: Increasing evidence shows that three dimensional cell culture models better reflect the in vivo tumor microenvironment than two dimensional cell culture models. Co-culture models are ideal cell culture models for understanding the communication between cells and the in vivo microenvironment. Changes in expression levels of E-cadherin are closely related to cancer metastasis and progression. β-catenin mediates cell adhesion of E-cadherin. Endothelial cells are stromal cell components in the tumor microenvironment. It is known that there is little or no expression of E-cadherin in endothelial cells.
Methods: In our study, both two-dimensional and three dimensional mono-culture and co-culture models were created using Huvec and Ishikawa cells (endometrial cancer cell lines) to better reflect cell interactions. Spheroids were followed for three days in the three-dimensional cell culture model. E-cadherin and β-catenin expression levels of two-dimensional and three dimensional mono-culture and co-culture models were measured by immunofluorescence staining. Spheroid images were recorded using a Z-stack. Intensity measurements in both two-dimensional and three-dimensional mono-culture and co-culture models were made using the Image J software. Study groups were evaluated by one-way analysis of variance (One-Way ANOVA). Values of p <0.05 were considered statistically significant.
Results: The size of the co-culture spheroids was recorded significantly larger than the mono-culture spheroids (p <0.0001). In two (p = 0.0175) and three dimensional models (p <0.0001), expression levels of E-cadherin in the mono-culture of Ishikawa cells were recorded significantly higher than in Huvec and co-culture cells. Likewise, while the expression levels of β-catenin were higher in the mono-culture of Ishikawa cells in two-dimensional models (p <0.05), no significant difference was observed in three dimensional models (p> 0.05).
Conclusion: In summary, it has been noted that the expression levels of E-cadherin are significantly reduced in co-cultures of Ishikawa cells with Huvec cells in both two and three dimensions . These results support the idea that endothelial cells may cause changes in endometrial cancer progression by suppressing E-cadherin expression in Ishikawa cells.
Keywords: Co-culture; E-cadherin; Immunofluorescence; Spheroid; β-catenin.