Gene expression in different culture conditions in breast cancer cell lines

Breast cancer has a high risk of recurrence and distant metastasis after remission. Controlling distant metastasis is important for reducing breast cancer mortality, but accomplishing this goal remains elusive. In this study, we aimed to find a way to control distant metastasis using a model that mimics the various forms of tumor cells present during distant metastasis. Breast cancer cells were cultured under two-dimensional (2D) adherent, tumor sphere (TS), and reattached (ReA) culture conditions to mimic primary tumors, circulating tumor cells, and metastasized tumors, respectively. ReA cells demonstrated increased TS formation, enhanced invasion capacity, and a higher frequency of ESA⁺CD44⁺CD24⁻ cells compared to the original 2D-cultured parental cells. In addition, RNA sequencing identified the cholesterol synthesis pathway as one of the most significantly increased pathways in TS and ReA cells compared to parental cells, which was verified by measuring intracellular cholesterol levels. Furthermore, the pharmacological inhibition of the cholesterol synthesis pathway decreased the ability of cancer cells to form TSs and invade. Our results suggest that the cholesterol synthesis pathway plays an important role in the distant metastasis of breast cancer cells by augmenting TS formation and invasion capacity. mRNA expression profiles of the breast cancer of Homo sapiens with different culture conditions were examined by Illumina Nova-seq 6000