microRNA validation in vivo - (Dec/01/2012 )

How can I test a microRNA as a tumor suppressor in vivo? i need some methods and protocols
Can I also examine the down - regulation of X target gene by a microRNA in vivo?

The questions are what delivery route are you going to use--local or systemic delivery. If it is local, it should not be a big deal. If it is systemic, you have to find a good delivery agent that can bring the miRNA to its target tissue or organ. Regardless of delivery route, you have to prove first that your miRNA reaches its target tissue and internalized by target cells, 2nd, it suppresses its target genes.