What are some of the possible complications of going "too far" in attempting to extend or improve human life?

I am writing an essay on Frankenstein and I am pondering the question, "What are some of the possible complications of going 'too far' in attempting to extend or improve human life?" I have already answered questions such as "Are there boundaries that human beings should not cross?" and "Who sets these boundaries?" I was able to relate them all back to Frankenstein. However, I am having a lot of trouble with this one- especially with relating it back to Frankenstein. Any help?