A promising target

Yale researchers have shown that an artificial gene switch can induce the growth of new blood vessels in a mouse model, a new approach to gene therapy that has implications for heart disease and cancer. The technique uses an engineered transcription factor to switch on inactive genes that are already present in the mouse and has the potential to spur the growth of new vessels in tissue that has a diminished blood supply. The principle could also be extended to control overactive genes that need switching off, such as those for cancerous tumor growth.

In previous gene therapy trials, patients have been injected with the genes that encode the growth factors that drive angiogenesis, the process of vessel formation. But Yale’s Frank J. Giordano, M.D., and colleagues at Sangamo BioSciences used a viral vector to deliver the genes that code for the switch, a zinc finger protein transcription factor dubbed Vegfa-ZFP. The mouse then produced the transcription factor, which switched on the growth genes. Healthy blood vessels formed and wound healing was augmented, according to the paper, published online in Nature Medicine on November 4.