I don't think it would be a good idea. If the alien life evolved completely independently, even if it was DNA and carbon-based, the problem you run into is one of chirality. All life on earth makes molecules with the same chirality (which is different for different molecules, but is consistent for each molecule). The chirality of the alien proteins being different from ours means it's unlikely we could make use of them in our digestion system, or worse, the alternatively-handed molecules would be poisonous to us. Remember Thalidomide? Only one of its chiral forms causes birth defects. Here's an article that explores the other possibility--of aliens landing on earth: https://medium.com/predict/aliens-could-starve-to-death-on-earth-8c2d12200229