Bold the dimension object value in Hyperlink tooltip

Hello everyone,

We've a column in a table (in Webi), which has Document Linking applied. We used formula to build the tool tip, which is ="Analysis Dashboard for Project: " + [Project Key]

We'd like to bold just the [Project Key] value in the tool tip to be in Bold, how do we do that? I've seen different forums talking about just formatting regular text as bold using <b>Text to be in bold here</b> syntax, but that's not what I'm looking for. Please help.

Thanks,
Mahboob Mohammed