 with obesity. So I think that's probably our leading hypothesis, but of course there are others. Okay, so we've seen obesity rise in all age groups in the United States. So help me understand a little bit more about, first of all, what it is about obesity that leads it to be a major risk factor for gastrointestinal cancers. And actually, Dr. Ying, I'm going to start with you about that. How does it trigger the development of a cancer?