Re:
Just try it as generally the front rings don't pose a problem. The chain pitch is the same its just the width. You will need some fine adjustments on the FD thats all;
Sheldon's comment re Front
Chain: As you go to more sprockets on the cassette, you need a narrower chain. However, using a chain one size narrower than standard rarely presents any problem. Thus, you can use a "9-speed" chain with a 7-speed or 8-speed system, or a "10-speed" chain with a 9-speed system. This is not the ideal approach -- shifting may not be quite as smooth -- but it's workable.
Narrow chains bring other problems, though. They are usually more expensive and -- with 10 or more speeds -- don't last as long -- even when used in the intended system.