Brd4 and other new drugs

cb, breast cancer cells that make it into the blood, then lungs, brain, or bones are still at their core breast cancer cells, with (for the most part) specific characteristic cell surface markers and pathways of functioning. While all cells in our bodies start out the same, they differentiate into various kinds of cells in utero. And once they're determined to be one kind of cell, they can't go back and change into another whole type of cell. Leukemias are blood cancers where you have abnormal (white) blood cancer cells in your blood. Breast cancer cells that happen to be in the blood don't work / look like / get killed the same way as blood cancer cells, so the same treatments don't work. Not to confuse the issue, but sometimes leukemia (blood cancer) cells make it into cerebrospinal fluid around the brain. But that doesn't mean that it's now brain cancer, or that it can be killed by brain cancer chemo, it just means it's blood cancer that's moved from its original location (the bloodstream) to somewhere it really doesn't belong (the brain). An analogy might be like when you're at the store and someone has left an apple on the shelf next to the rice chex in the grocery aisle. It's still fruit, not cereal, just where it really doesn't belong, away from all the things like it after having hopped on someone's cart (bloodstream) to get there. Hope that helps a little!