Specifically, the co-localization of p75ICD and the marker ABCG2 was observed in invasive carcinoma CSCs, where ABCG2 staining was perinuclear within cells as well as pericellular (asterisks), as expected based on the ABCG2 expression in extracellular vesicles in squamous cancer. The gene discussed is ABCG2; the disease is invasive carcinoma.