Enhanced angiogenesis and growth of 12-lipoxygenase gene-transfected MCF-7 human breast cancer cells in athymic nude mice.

Transfection of the estrogen-dependent and poorly invasive MCF-7 human breast cancer cell line so that it stably overexpressed 12-lipoxygenase and secreted high levels of 12-hydroxyeicosatetraenoic acid when cultured with arachidonate resulted in rapid growth in athymic nude mice when compared with the parental line. This enhanced acquisition of tumor mass was a result of both increased cell proliferation and reduced apoptotic cell death and was accompanied by high angiogenic activity.