Jao Tzu-Ming, Li Ya-Lin, Lin Shu-Wha, Tzeng Sheng-Tai, Yu I-Shing, Yen Sou-Jhy, Tsai Ming-Hong, Yang Ya-Chien
Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, Taipei, Taiwan.
Department of Laboratory Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Oncotarget. 2016 Dec 20;7(51):84938-84950. doi: 10.18632/oncotarget.12915.
Glucosaminyl N-deacetylase/N-sulfotransferases (NDSTs) are the first enzymes that mediate the initiation of heparan sulfate sulfation. We previously identified NDST4 as a putative tumor suppressor in human colorectal cancer. In the study, we generated an Ndst4 knockout (Ndst4-/-) mouse strain and explored its phenotypic characteristics, particularly in the development of colonic epithelial homeostasis. The Ndst4-deficient mice were viable and fertile, and their life spans were similar to those of wild-type littermates. No gross behavioral or morphological differences were observed between the Ndst4-/- and wild-type mice, and no significant changes were determined in the hematological or serum biochemical parameters of the Ndst4-/- mice. Ndst4 RNA transcripts were expressed in the brain, lung, gastrointestinal tract, pancreas, and ovary. However, Ndst4-null mice exhibited no gross or histological abnormalities in the studied organs, except for the colon. Although no alterations were observed in the crypt length or number of proliferating cells, the Ndst4-/- mice exhibited an increased number of goblet cells and a decreased number of colonocytes in the proximal colon compared with the wild-type mice. Moreover, Ndst4 deficiency increased the basal level of apoptosis in the colonic epithelium. Taken together, we established, for the first time, an Ndst4-/- mouse strain and revealed the involvement of Ndst4 in the development and homeostasis of colonic epithelium. Accordingly, NDST4 in human colon might direct the biosynthesis of specific heparan sulfate proteoglycans that are essential for the maintenance of colonic epithelial homeostasis. Thus, the loss of its function may result in the tumorigenesis and progression of colorectal cancer.
氨基葡萄糖N - 脱乙酰酶/N - 磺基转移酶(NDSTs)是介导硫酸乙酰肝素硫酸化起始的首批酶。我们之前将NDST4鉴定为人类结直肠癌中的一种假定肿瘤抑制因子。在本研究中,我们构建了一种Ndst4基因敲除(Ndst4-/-)小鼠品系,并探究了其表型特征,尤其是在结肠上皮内稳态发展方面的特征。缺乏Ndst4的小鼠能够存活且可育,其寿命与野生型同窝小鼠相似。在Ndst4-/-小鼠与野生型小鼠之间未观察到明显的行为或形态差异,并且在Ndst4-/-小鼠的血液学或血清生化参数中未确定有显著变化。Ndst4 RNA转录本在脑、肺、胃肠道、胰腺和卵巢中表达。然而,除结肠外,Ndst4基因敲除小鼠在所研究的器官中未表现出明显或组织学异常。尽管在隐窝长度或增殖细胞数量上未观察到改变,但与野生型小鼠相比,Ndst4-/-小鼠近端结肠中的杯状细胞数量增加,结肠细胞数量减少。此外,Ndst4缺乏增加了结肠上皮细胞的基础凋亡水平。综上所述,我们首次构建了Ndst4-/-小鼠品系,并揭示了Ndst4参与结肠上皮的发育和内稳态维持。因此,人类结肠中的NDST4可能指导特定硫酸乙酰肝素蛋白聚糖的生物合成,而这些蛋白聚糖对于维持结肠上皮内稳态至关重要。因此,其功能丧失可能导致结直肠癌的发生和进展。