Figure 3.

TEM carry a lymphatic phenotype in human breast tumor. The expression of (A) the lymphatic markers VEGFR-2, LYVE-1, VEGFR-3, Podoplanin, and PROX-1 and (B) the VEGFR co-receptors Neuropilin-1 and Neuropilin-2 was examined in breast tumor sections by confocal microscopy. Representative images from minimum five patients; (C) Some TEM formed small cell aggregates (10–100 cells); (D) PROX1 expression analysis was performed by RT-PCR from mRNA isolated from mouse cells (negative control), LEC in culture (positive control) and from TEM (CD14⁺CD45⁺ cells) sorted by flow cytometry from dissociated breast tumor. One representative gene expression profile from 10-cell samples from one patient is shown out of 32 cell samples from four patients (8 samples/patient of 10 cells each); (E) Immunofluorescence labeling in sections of non-neoplastic breast tissue adjacent to tumor tissues shows no detectable expression of Podoplanin and VEGFR-3. Non-neoplastic (panel E) and tumor tissue (panel A and C) were stained and imaged simultaneously under the same conditions and thus intensities of the expression of Podoplanin and VEGFR-3 signals can be compared. Scale bars (A-C and E): 25 μm, (A) higher magnification, scale bar: 10 μm.