 As we've seen, the cooked meat carcinogen FIP can cause DNA mutations that may initiate a tumor, may then promote the growth of the cancer due to its potent estrogenic activity, and the third strike is that FIP may then promote the invasiveness of breast cancer cells. The way breast tumors kill is by metastasis. It's got to invade surrounding tissues and organs. The way you test invasiveness is you put cancer cells in what's called an invasion chamber. Cancer cells go on the top, on one side of a membrane, with tiny pores, these little gray circles. This is the underside of the filter, showing no invasion, but add some estrogen, and you can see a few cancer cells peeking through. Add some FIP, and they really start going on the move. More breast cancer cell invasion promoting than straight estrogen. They conclude that in addition to its well-characterized genotoxic potential, DNA mutation-causing potential, FIP is potently estrogenic, is capable of powerful hormonal activity, and is able to potently stimulate breast cancer cells to invade through a membrane model. The FIP is able to exert this proinvasive appearance in breast cancer cells that such low concentrations is remarkable. The genetic toxicity of the compound, coupled to its ability to enhance cell proliferation and invasion, indicates that FIP can act not only to initiate the carcinogenic process, but also to promote it. The problem is, they say, that exposure to FIP is difficult to avoid, because of its presence in many commonly consumed cooked meats, particularly chicken, beef, and fish. But if you're able to somehow dodge cooked meats and don't suck on a cigarette, tailpipe, or incinerator smokestack, maybe it's not so difficult to avoid after all.