on the subject of or in connection with; about

we are given little information concerning matters of national security

causing anxiety; worrying

I find many of the comments very concerning

a concerning breach of security

relate to; be about

the story concerns a friend of mine

the report is mainly concerned with 1984 onwards

make (someone) anxious or worried

the roof of the barn concerns me because eventually it will fall in

don't concern yourself, old boy—my lips are sealed