Humanists are quite an interesting phenomenon. From my point of experience, there are at least two types of current organizations that use the Humanist label:
a.) Those which are secular counter-clubs to confessional Christianity, celebrating coming-of-age-parties, offering secular rituals for weddings and funerals and so on. Historically, they emerged 100-200 years ago. In Germany for example, they are even registered as "Churchs" which gives them certain kinds of privileges.
b.) Atheist propagandists which proclaim science and evolutionary theory as illuminating forces and themselves as experts.
The other question is - consider Humanists themselves Epicureans? I would deny this question but nonetheless they frequently point to Epicurus when it comes to historical precursors giving them legetimacy.