Professor X and Magneto are the two pillars of the X-Men universe as adapted for the big screen until now. That, however, might come to an end.
It's been repeatedly stated and now it's known: X-Men: Apocalypse will be a game-changer, altering the history of the universe as built since the early 2000s.
This change will, possibility, also impact the status of Professor X and Magneto, as well as the relation between the two veterans.
In fact, if X-Men: Apocalypse pulls to whatever degree from Age of Apocalypse, it's more than possible. It's basically certain: Professor X is going to die.
How does Professor X die in the comic book?

The event which kicks off Age of Apocalypse is, in fact the very death of Professor X. In an attempt to stop the present from happening as it did by the making of Magneto, Charles Xavier's son travels back in time.

