Oriental bittersweet, Celastrus orbiculatus. I don't believe the plant is poisonous, tho I wouldn't try eating the berries. The American bittersweet has mildly toxic berries. This vine could strangle your apple tree if not removed.

Thank you for your response. It’s on my neighbor’s property, but overhanging mine. She plans to remove the Poison Ivy, (which is massive), so I will let her know about the danger to her Lilac, as well. Btw, this is in the Hudson Valley, NY.