Differential Response to Cisplatin between Co-cultured Cells and Pure Cultured Cells Based on Single-cell RNA Sequencing of Three-dimensional-cultured Breast Cancer Cells

Abstract

Objective: The current study aimed to develop an experimental approach for the direct co-culture of three-dimensional breast cancer cells using single-cell RNA sequencing (scRNA-seq).

Methods: The following four cell culture groups were established in the Matrigel matrix: the untreated Michigan Cancer Foundation (MCF)-7 cell culture group, the MCF-7 cell culture plus cisplatin group, the untreated co-culture group, and the cell co-culture plus cisplatin group. For cell co-culture, MCF-7 cells, human mammary fibroblasts, and human umbilical vein endothelial cells were mixed at a ratio of 1:1:1. Cisplatin was applied at a concentration of 1.25 μg/mL, and the cells were harvested after 2 days and subjected to scRNA-seq. Data were analyzed using a single-cell RNA sequencing data analysis pipeline with R language.

Results: The response of MCF-7 cells to cisplatin differed among the four groups. The transcriptomic response of MCF-7 cells to cisplatin in the co-culture model was not as significant as that in the mono-culture model. Moreover, the pathways related to apoptosis, DNA damage, hypoxia, and metastasis in the co-culture groups were enriched in the genes that were differentially expressed based on cisplatin treatment.

Conclusion: scRNA-seq analysis revealed that the response of MCF-7 cells to cisplatin in the co-culture model was lower than that in the mono-culture model. Therefore, the three-dimensional cell co-culture model can be applied to tumor research to better mimic the pathophysiological environment in vivo and can be a well-modified research method.

Keywords: MCF-7 cells; breast cancer; single-cell RNA sequencing; three-dimensional cell coculture.