NAFAIK. You may have to do that externally.
When you have a lot of titling, make a draft in Word e.g. Have the spellings checker check it for you and then copy it into the titler.
I've filed a request for a spell-check in Titler, since PrPro2. So far, nothing. OTOH, with some of the little problems in Titler, maybe I should be glad. Hve never seen a spell-check plug-in.
I do as Ann suggests, and use the word processor for anthing beyond a few simple Titles. Even then, I find mistakes!
Also, I usually do most major Titling in PS from the Word/WordPerfect documents, and Import as .PSD Footage.