revolve around vs concern

revolve around is not a noun while concern is a noun.

Word	Noun	Adjective	Verb	Adverb
revolve around	No	No	Yes	No
concern	Yes	No	Yes	No

As verbs, concern is a hypernym of revolve around; that is, concern is a word with a broader meaning than revolve around:

Other hypernyms of revolve around include bear on, come to, have to do with, pertain, refer, relate, touch, touch on.

revolve around (noun)	concern (noun)
	something that interests you because it is important or affects you
	something or someone that causes anxiety; a source of unhappiness
	a feeling of sympathy for someone or something
	an anxious feeling
	a commercial or industrial enterprise and the people who constitute it

revolve around (verb)	concern (verb)
move around in a circular motion	be relevant to
center upon	be on the mind of