wood, even something like pine, has an amazing strength end-to-end. i assume you mean that your stand looks a little like a table, w/ four posts and a solid piece on top? something like that should hold, but you may have problems with the wood of the legs buckling slightly over time, and a brace around the legs halfway down or so would quickly solve that problem. you wouldn't really really need pieces to go under your solid top, but being just a tad paranoid, and with a tank that big, i'd put a few anyway. i mean, better safe than sorry, when sorry is 110 gallons of water on your floor, right?
another thing to consider is that, often with tanks that size, people will build their stand with six legs -- a pair in the middle. this would also offer added stability and strength.