1) In a 2-inch deep dish, arrange the tuna steaks.
2) In a bowl, add Italian dressing, soy sauce and lemon juice.
3) Pour the dressing over the tuna steaks. Cover the dish and keep it in the fridge to marinate for about 1 hour. Turn the steaks over once during the marination time.
4) Over a medium-hot grill, grill the tuna steaks for about 5 minutes on each side or until done. Baste the steaks with the spice dressing intermittently.
5) Garnish the tuna steaks with thinly-sliced lemon wedges on the top or sides.
6) Serve hot.