Fig. 1

a Proliferation assay. OVCAR3 were plated and counted every 2 days in presence or not of E4⁺ECs for 6 days. b Proliferation assay in transwell. OVCAR3 were grown in a Transwell system and counted every 2 days in presence or not of E4⁺ECs for 6 days. c Representative pictures of the ovarian tumor seen after sacrifice of the mice. The table displays the xenograft tumor size for each mouse in millimeters (length × width). d The graph represents the tumor weight for each mouse in both groups. e Tumors were snap-frozen after isolation and then sectioned to 10 µm for immuno-staining. Slides were stained with anti-human CD31 and anti-mouse CD31 antibodies, DAPI and Immunofluorescence images were acquired in confocal microscopy. f Tumors were snap-frozen after isolation and then sectioned to 10 µm for immuno-staining. Slides were stained with anti-human CD31 and anti-human Ki67 antibodies, DAPI and Immunofluorescence images were acquired in confocal microscopy