With the buzz that the OT cast are getting just from appearing in Days of Future Past, Fox would likely to bring them back most especially if DOFP ends up grossing more than $500 million worldwide.
"This is our chance to make a difference" - Sue Storm - The Invisible Woman
"He's stronger than any of us but he's not stronger than all of us" - Reed Richards - Mr. Fantastic
"We could these powers to help people" - Johnny Storm - The Human Torch
"You can't fix this, nobody can" - Ben Grimm - The Thing