Fig. 4: Cutaneous 4T1 cells exhibit the angiogenic and skin-metastatic properties characteristic of breast cancer cells.

A Primary 4T1 cells were subcutaneously implanted into immunocompromised mice, allowed to form tumors, and surgically removed upon reaching 100-150 mm³ tumor size. Post-surgery mice were monitored for two weeks while daily intraperitoneal injections of adipocyte-conditioned medium were administered. After two weeks, mice were dissected to examine tumor recurrence on the dorsal and ventral sides. B Hematoxylin and eosin (H&E) staining and IHC staining of VEGF, CD31, and VEGFC in cutaneous tumor tissues of mice. C Microscopic cell morphology of 4T1 and cutaneous 4T1 cells. D Comparison of Lung Metastasis Induced by Parental and Cutaneous 4T1 Cells in Mice. E Mouse Cytokine Antibody Array Kits (R&D) were applied to measure the content of 111 cytokines in the 4T1 and cutaneous 4T1 cells. Cytokines upregulated in cutaneous 4T1 and indicated by colored boxes are VEGF (red), CCL2 (green), CCL5 (blue), ANGPT 1 (light blue), and ANGPT2 2 (dark green). Highlighted rectangles indicate the cytokines elevated. F An RT-qPCR analysis of Vegf, Vegfc, Ccl2, Ccl5, Angpt1, Angpt2, Lep, and Ptgis mRNA expression in 4T1 and cutaneous 4T1 cells. Columns represent the mean results from PCR assays performed in triplicate and normalized to GAPDH (*P < 0.05). G IHC staining of CCL-2, CCL5, and ANGPT2 in tumor and cutaneous tumor tissues of the patient.