BACKGROUND<\/p>\n
Pregnant women with breast cancer present with a more advanced disease compared with non-pregnant women. Nevertheless, breast cancer metastasis to the placenta is rare. Trophoblast\/tumor implantations share the same biochemical mediators, while only the first is stringently controlled. We hypothesized that the same mechanisms that affect\/restrain placental implantation may inhibit metastatic growth in the placenta. We aimed to analyze the effects of human placenta on breast cancer cells.<\/p>\n
METHODS<\/p>\n
First trimester human placental explants were co-cultured with MCF-7\/T47D-eGFP tagged cells. Following culture, placenta\/cancer cells\/both were fixed, paraffin embedded and sliced for immunohistochemical analysis or sorted by their eGFP expression for future analysis. The tested parameters were: proliferation (immunohistochemistry)\/cell cycle (FACS), apoptosis (immunohistochemistry\/FACS), cell count\/adhesion\/distribution around the placenta (cell sorter, visual observation and counting), matrix metalloproteinase activity (zymogram) and estrogen receptor (ER) expression (western blotting, immunohistochemistry).<\/p>\n
RESULTS<\/p>\n
Reduced breast cancer cell numbers (45%, 48% for MCF-7\/T47D, respectively, P<\/I> < 0.05) were observed near the placenta. The placenta elevated MCF-7 sub-G1 phase and modestly elevated apoptosis (3–17% for T47D\/MCF-7, respectively, P<\/I> < 0.05). Our findings demonstrate breast cancer cell migration from the placenta as: (i) T47D\/MCF-7 cells changed their morphology to that of motile cells; (ii) elevated MMPs activity was found in the co-culture; (iii) placental soluble factors detached breast cancer cells; and (4) the placenta reduced MCF-7\/T47D cells' ER expression (a characteristic of motile cells).<\/p>\n
CONCLUSIONS<\/p>\n
MCF-7\/T47D cells are eliminated from the placental surroundings. Analyzing the causes of these phenomena may suggest biological pathways for this event and raise new therapeutic targets.<\/p>\n","protected":false},"excerpt":{"rendered":"
BACKGROUND Pregnant women with breast cancer present with a more advanced disease compared with non-pregnant women. Nevertheless, breast cancer metastasis to the placenta is rare. Trophoblast\/tumor implantations share the same biochemical mediators, while only the first is stringently controlled. We … Continue reading