Hi, we have recently started to use the CAM model and are at the moment rather successful in keeping embryos up to 14 days.

The next step for us is to grow tumors on the cam and look at angiogenesis. The growing of tumors is a little difficult though. First I'll give you the procedure.

At day 6-7 after activation we put the cells (PC3) onto the CAM. This we do at a branching point in the vasculature by putting a thin plastic ring (cut from a 1 ml plastic pipette) onto the cam and adding the cells (2-3 millions) in growth medium/matrigel 1:1 50 µl.

One problem we are experiencing is that the ring is moving around a lot. How is this prevented? From the literature we have found, this seems to be a rather standard method. When the ring is moving, we loos track of the cancer cells. Some protocols scrape the surface of the CAM to initiate angiogenesis. This could possible help in getting the ring to grow stuck as well?

Does anyone have some suggestions on how to get tumors growing efficiently in CAMs? What is your tumor take rate?