November 12, 2014 – Of Mice and Cancer


Anchor lead: Should you spend money on your own mouse model of your cancer? Elizabeth Tracey reports

Should people with cancer pay for their own model of their tumor grown in a mouse?  That’s what a couple of commercial enterprises propose, saying that therapies can then be tested in this so-called avatar.  But such an avatar doesn’t take into account the fact that a person’s tumor is constantly growing and changing genetically, Stephen Desiderio, director of the institute of basic biomedical sciences at Johns Hopkins, asserts.

Desiderio: What you’re testing in the mouse is not targeting genetically what’s in the host.  And you can’t have it two ways. If you want to say that you’re doing individualized cancer medicine by taking the host’s own well characterized tumors and putting them in the mouse you better check the mouse to make sure that the composition of the tumor at the time you test is the same as the composition in the human. That’s got to be done.   :22

This quality of cancers is known as tumor heterogeneity, with studies demonstrating that even at a single point in time, tumors in different locations in the same person may be genetically distinct.  At Johns Hopkins, I’m Elizabeth Tracey.