Characterization of a luminal breast cancer patient-derived xenograft (PDX) via single-cell RNA-sequencing (scRNA-seq)

Luminal breast cancers are characterized by estrogen-regulated gene profiles. We performed scRNA-seq on a luminal breast cancer PDX named GS1 to profile the gene expression of the cells constituting GS1 tumor and to investigate the effect of estrogen on the individual populations. GS1 has shown a luminal-B like feature with low estrogen receptor (ER) expression (5%). Because the growth of this tumor can be partly promoted by the addition of estrogen but also grow without estrogen, GS1 has been defined as an estrogen-accelerating luminal breast cancer model. GS1 tumors from control, 17β-estradiol (E2), and E2 + ICI 182, 780 (ER antagonist; ICI) groups were analyzed using scRNA-seq.