How to Replace a Comma with a space in a Derived Column

I'm trying to replace any commas in a column with a space. I'm using the following in a derived column: 

(DT_TEXT)REPLACE([VendorMasterName] ,"-","")

Anytime I try to save the Derived Column, I'm receiving the following error: 

Error at Data Flow Task [Derived Column [218]]: Attempt to parse the expression "(DT_TEXT)REPLACE([VendorMasterName],",","")" failed. The expression might contain an invalid token, an incomplete token, or an invalid element. It might not be well-formed, or might be missing part of a required element such as a parenthesis. 

I've also Tried the following:

(DT_STR)REPLACE([VendorMasterName] ,"-","")

(DT_TEXT)REPLACE([VendorMasterName] ,'-','')

Any help would be greatly appreciated! 

Thank You