FIGURE 6:

MCF-7 CXCR4∆CTD cells express MMP-2 and both MCF-7 CXCR4∆CTD cells and MCF-7 CXCR4WT cells exhibit lymphatic metastasis. (a) Zymographic analysis of MMP-2 and MMP-9. MCF-7 and MCF-7 CXCR4ΔCTD cells were analyzed for MMP-2 and MMP-9 expression using polyacrylamide gels embedded with 0.1 mg/ml gelatin. HT1080 cells are a positive control for MMP-2 and MMP-9 activity. (b) Optical in vivo imaging of nude mice with GFP-expressing MCF-7 vector control, GFP-MCF-7 CXCR4 WT, or GFP-MCF-7 CXCR4ΔCTD tumors at 3, 4, and 5 wk after orthotopic implantation of cells into either the third or the fourth mammary gland. Encircled areas represent regions of interest for assessment of tumor growth. (c) Representative images of primary tumors and lymph node metastases of GFP-MCF-7 CXCR4WT tumors. Fluorescence microscopy of metastases from a tumor bearing GFP-MCF-7 CXCR4WT cells at the inguinal lymph node near the tumor from mouse 1 (xenograft in the fourth mammary gland) and the axillary lymph nodes near the tumor from mice 3–5 (xenograft in the third mammary gland). Tissues from tumor and lymph nodes were dissected and examined using fluorescence microscopy. Bars, 150 μm. (d) Representative images of primary tumors and lymph node metastases of GFP-MCF-7 CXCR4ΔCTD tumors. Fluorescence microscopy of metastases from a tumor bearing GFP-MCF-7 CXCR4ΔCTD cells at the inguinal lymph node near the tumor from mice 1 and 2 (xenograft in the fourth mammary gland) and the axillary lymph nodes near the tumor from mice 3 and 4 (xenograft in the third mammary gland).