Immunohistochemical staining of breast cancer MCTs derived from surgical samples of human breast cancer tissue reveals a heterogeneous mixture of cellular components within spheroids, including epithelial markers (PanCK), fibroblast markers (Vimentin), and breast cancer-specific markers (ER, PR, Her2, Mammaglobin, GATA) [165]. The gene discussed is QRSL1; the disease is breast cancer.