Vitamin D differentially regulates colon stem cells in patient-derived normal and tumor organoids
Vitamin D differentially regulates colon stem cells in patient-derived normal and tumor organoids
复制标题
DOI：
10.1111/febs.14998
复制
发表时间：
2019-07-29
期刊：
影响因子：
5.4
通讯作者：
Barbachan, Antonio
中科院分区：
文献类型：
--
作者：
Fernandez-Barral, Asuncion;Costales-Carrer, Alba;Barbachan, Antonio
肠道是维生素D的主要靶点，一些研究表明维生素D缺乏症与炎症性肠病（IBD）之间存在关联，但也增加了结直肠癌（CRC）的风险和死亡率。然而，活性维生素D代谢物1 α，25-二羟基维生素D-3（骨化三醇）对人类结肠干细胞的推定作用尚不清楚。在这里，我们通过免疫组织化学和RNAscope原位杂交显示，维生素D受体（VDR）出乎意料地表达于人体组织中的LGR 5（+）结肠干细胞以及患者活检产生的正常和肿瘤类器官培养物中。有趣的是，正常和肿瘤类器官对骨化三醇的反应不同，其转录组学特征发生了深刻而鲜明的变化。在正常类器官中，骨化三醇上调干细胞相关基因，如LGR 5，SMOC 2，LRIG 1，MSI 1，PTK 7和MEX 3A，并抑制细胞增殖。相比之下，在肿瘤类器官中，骨化三醇对干细胞相关基因的影响很小，同时它诱导分化的表型，并且骨化三醇减少细胞增殖。一致地，电子显微镜显示骨化三醇不影响正常类器官中的母细胞未分化细胞表型，但其诱导肿瘤类器官中的一系列分化特征。我们的研究结果首次证明了维生素D对人类结肠干细胞的调节作用，表明对结肠上皮细胞的稳态作用与IBD和CRC的相关影响。
Intestine is a major target of vitamin D and several studies indicate an association between vitamin D deficiency and inflammatory bowel diseases (IBD), but also increased colorectal cancer (CRC) risk and mortality. However, the putative effects of 1 alpha,25-dihydroxyvitamin D-3 (calcitriol), the active vitamin D metabolite, on human colonic stem cells are unknown. Here we show by immunohistochemistry and RNAscope in situ hybridization that vitamin D receptor (VDR) is unexpectedly expressed in LGR5(+) colon stem cells in human tissue and in normal and tumor organoid cultures generated from patient biopsies. Interestingly, normal and tumor organoids respond differentially to calcitriol with profound and contrasting changes in their transcriptomic profiles. In normal organoids, calcitriol upregulates stemness-related genes, such as LGR5, SMOC2, LRIG1, MSI1, PTK7, and MEX3A, and inhibits cell proliferation. In contrast, in tumor organoids calcitriol has little effect on stemness-related genes while it induces a differentiated phenotype, and variably reduces cell proliferation. Concordantly, electron microscopy showed that calcitriol does not affect the blastic undifferentiated cell phenotype in normal organoids but it induces a series of differentiated features in tumor organoids. Our results constitute the first demonstration of a regulatory role of vitamin D on human colon stem cells, indicating a homeostatic effect on colon epithelium with relevant implications in IBD and CRC.