dropping a comma from a string variable

Hi,
I would appreciate your help please in dropping a comma

I've created a string variable in the "Variable Editor" which goes like this:

        =Year([due_date])+"-"+"Q"+Quarter([due_date])

        *[due_date] is a date variable

I was wondering how can I drop a comma from year segment of the result

instead      2,016-Q4

to receive  2016-Q4

Thank You