The relationship of vitamin D receptor and β-catenin pathway in intestinal tumor growth / 中国医师杂志

ABSTRACT

Objective To explore the effect of vitamin D receptor (VDR) in intestinal tumor development and the relationship between VDR and β-catenin signaling pathway. Methods The interaction of vitamin D receptor and β-catenin were detected by co-immunoprecipitation assay after human colonic carcinoma cells SW480 were treated with vitamin D in vitro for 4 hours. The expression of E-cadherin protein was detected by Western blot after treated for 24 hours. To compare APCmin/+VDR-/- and APCmin/+ mice in vivo, the expression of VDR,β-catenin and BrdU proteins in intestinal tumor were determined by immunohistochemistry. The expression of β-catenin protein in tumor and adjacency intestinal was further determined by Western blot. Results After SW480 cells were treated with vitamin D, vitamin D receptor and β-catenin protein showed binding, the expression of E-cadherin protein further increased (Gray value the control group 145.57±4.21,Gray value of the experimental group 109.35±3.56,t＝32.63,P＜0.05). Immunostaining and Western blot detection（Gray value 166.47±2.36） showed a marked increase of β-catenin level(Gray value 140.51±2.57) in APCmin/+VDR-/- tumor compared to APCmin/+ tumor(145.41±3.62,182.35±3.24,t＝2.65,4.36,P＜0.05). Conclusions The role of vitamin D suppressing intestinal tumor may be achieved through VDR affectingβ-catenin signaling pathway.