That's entirely besides the point, though. These cell lines are not used as a model of cancer they're used as a model of human cells. Those working with them understand the limitations of the model (most of the time, at least); it's well known that cell lines are not the same thing as cells in a live organism, no one was assuming otherwise.
There is no new information here. This is a little like looking at humans and mice, noticing that they are different, and announcing that this "Invalidates all research done on mice!"
Please don't assume that all researchers are idiots all of the time.