Mischa Barton was supposed to host the opening of the new CatHouse in the Strip's Luxor Hotel and Casino in Las Vegas but she canceled after her arrest for DUI and drug possession the day before.Even though the official statement from the club was that THEY canceled, a representative for the club says that the former O.C. star is expected to make it up to them. “Mischa did not show up last night as expected,” the rep said. "She still has to honor her contract, and what happens next remains to be seen. I’ll keep you posted."