Identify comic book story about alien who lived several lives

I read the story in the '50s.

The story was probably in a DC comic.

A college professor uses hypnosis to discover people's past lives (like Bridie Murphy). He discovers that one of his subjects is an alien android who lived as many historic leaders. His last life before the present was Adolph Hitler. His current life is as a custodian at the college.

I'd like to identify the story so that I can find more of the author's work.