Well, This is My own Piece of "Wisdom" in this topic But I think Yes, there Are differences, I may be right or May be wrong, yet again, It's only MY view of things:
First of All, There is a Difference A whore is someone profiting with herself (Either by pure sex or Monetary Gain), Personally I see them as low (Only the THINGS are lower) IF Applied to BDSM; so I use the term "whore" as an insult. While a slave is someone that GIVES HIMSELF/HERSELF to an owner, to do with She/He as he/she pleases, Out of Love or necessity, Being a slave Means being anything your owner wishes you to be. again, is a matter of desire of both parts. Finally a submissive is a being whom Keeps his/her self, yet decides to Gift us Dominants with his/her Submission...

These are my two cents
MELY