Nuclear receptors as molecular regulator and chemopreventive targets of colon cancer stem cells.

越来越多的证据表明，结肠癌干细胞（CCSC）与癌症的发生、发展和复发有关。为了在CCSC中建立与结肠癌发生和发展有关的信号通路，我们检测了来自已建立细胞系的CCSC中富集的结肠球中的核受体信号。我们发现结肠癌细胞系形成的结肠球高度富集CCSC，并且Wnt/b-catenin通路在结肠球的生长和维持中起关键作用。我们还发现岩藻黄嘌呤与1a，25-二羟基维生素D3联合通过下调PPARg和NFkB p52来作用于CCSC细胞的生长，并作为预防结肠癌的内在因素。这些发现证实了PPARg和维生素D受体（VDR）通过核信号通路之间的功能相关的串扰，在结肠癌细胞生长调控中起关键作用。

Increasing evidence suggests that colon cancer stem cells (CCSC) have responsible for carcinogenesis, cancer development and recurrence. To establish signaling pathways in CCSC, which are implicated in the initiation and progression of colon cancer, we examined nuclear receptor signaling in colonospheres that are enriched in CCSC from established cell lines. We found that colonospheres formed by colon cancer cell lines are highly enriched in CCSC and that Wnt/b-catenin pathway plays a critical role in growth and maintenance of colonospheres. We also found that the combination of Fucoxanthinol and 1a,25-dihydroxyvitamin D3 acts on the CCSC cell growth through down-regulation of PPARg and NFkB p52, and as an intrinsic factor for the prevention of colon cancer. These findings establish a critical role for PPARg and vitamin D receptor (VDR) in growth regulation in colon cancer cells via functionally relevant cross-talk between these nuclear signaling pathways.