Cx denotes speed. CA is 200, CH is 400 and CZ is 800. I'm going to assume that C would be for Color but Acros doesn't have Bx135 on the cassette. The DXf (Fuji) and DXn (Kodak) denote edge coding on the film itself for automatic scanners to read. I could be mistaken on the Cx suffixes but it seems logical.
OF Dr. Google turned up this old thread - I was wondering what is involved with the DXf system. is their any handy dandy date sheet explaining it. I have noticed a few rolls of Fuji colour have bar codes on Both edges of the film. I assume that is from the DXf but as we all know Fuji does not always tell us clearly