[Tenchi Hou Take]

Originally Posted by Krono

Pretty much every cancelled series ever.

Beyond that, I'm fairly certain the "announcement" that Hitman Reborn was ending came the chapter it ended, to give an example. Likewise, the "announcement" of Bakuman ending seems to have been in it's final chapter. So yeah, a Jump series ending without an announcement beforehand is pretty commonplace.

Actually with most major series even some minor (e.g shounen jump) they give a notice, it's more simply that notice isn't always translated in english, so you don't actually see it, but typically they do exist.