At the risk of answering without a guaranteed answer, "probably not," given the amount of the power necessary to drive that screen and complex architecture inside the box to make it work. But Target Display Mode as a thing has been around for a while.
I'm here to confirm to you that it doesn't. Sorry buddy, wish it did myself. 5K is out of reach for most MBP's (if not all).
That's a bummer, it would be worth buying a new iMac for the screen alone.