Newscasters in US on CNN are changing (10)
I believe the answer is:
announcers
'newscasters' is the definition.
(announcer can mean a news presenter)
'us on cnn are changing' is the wordplay.
'changing' indicates anagramming the letters.
'us'+'on'+'cnn'+'are'='usoncnnare'
'usoncnnare' with letters rearranged gives 'ANNOUNCERS'.
'in' is the link.
(Other definitions for announcers that I've seen before include "Hosts" , "Presenters" .)