It depends on how much time you want to put into it. It is possible to change that But It will take time and work.. Check out this guy
http://www.siriuspup.com/about_founder.html
He has a lot of good articles.
Victoria Stillwell has had a couple of shows about dogs like that. She has her own FB page and she does answer on there. Just ask her to point you in the direction of some articles.
Also look here for some articles .. Her I know personally and she has NEVER done the "alpha" training.
http://www.mybestbuddydogtraining.com/
I hope things work out.
It IS fixable.