Figure 1. Human DCIS tissue generates spheroids and pseudoductal structures in ex vivo culture and xenograft neoplasms.

(A) H&E stain of human breast DCIS, grade III with comedo necrosis (case 08-352), that represents the primary surgical source material for our organoid culture model system (10×). (B) DCIS cultured neoplastic cell exhibited autologous stromal invasion (20×). (C) H&E stain of multi-layered pleomorphic epithelial cells growing on the surface of autologous breast stroma after 12 weeks in culture (20×). Organoid culture of human DCIS lesions in serum free conditions spontaneously yielded (D) epithelial spheroids (10×) with a single spheroid shown in (E) (40×) and (F) pseudoductal structures with lumen formation (20×). (G) Human DCIS organoids or spheroids transplanted in NOD SCID mice induced tumor formation at the mammary fat pad transplantation site within 2 months. Xenograft tumors were greater than 16 mm² (length x width) as measured with calipers. (H) H&E stain of murine xenograft tumor (100×). Note pleomorphic epithelial cells with prominent nucleoli, stromal invasion and partial glandular differentiation. (I) Murine xenograft tumors derived from human DCIS cells were shown to be of human origin by the presence of human-specific epithelial antigen in formalin fixed paraffin embedded tissue sections. EpCAM-FITC (pseudo-colored green, 488 nm) and DAPI (psuedo-colored blue, 408 nm) (20× objective).