Getty Images On Thursday, the Chicago Bears will hold an off-season practice in Lake Forest, Ill. Then, around 1:30 p.m., team chairman George McCaskey, coach Matt Nagy and other Bears coaches and officials will board a van for a 3.5-hour ride south. On the van will be the guest of honor for a fundraiser Thursday night that’s unlike any charity event connected to the NFL these days. It’s a cancer fundraiser, with Bears defensive coordinator Chuck Pagano the man of the evening. It’s the seventh annual Chuckstrong Tailgate Gala. The first six have raised more than $5.5 million for cancer research. But this year’s is different. Pagano, whose very public conquest of leukemia in 2012 was one of the great feel-good stories of recent NFL seasons, was fired by the Colts 16 months ago. Coaches who get fired go away quietly and stay away. They don’t say what they really feel most often—that they were wronged, that they weren’t the problem. The firing team moves on, and rarely mentions the vanquished coach. The Colts are different. Pagano is different. Indianapolis is different. And now the Chicago Bears are in the Pagano web. “I’m not bitter,” Pagano said from Illinois the…