Department of Urology, Johann Wolfgang Goethe-University, 60590 Frankfurt am Main, Germany.
Exp Biol Med (Maywood). 2013 Nov 1;238(11):1297-304. doi: 10.1177/1535370213498975. Epub 2013 Sep 4.
The influence of the histone deacetylase (HDAC)-inhibitor, valproic acid (VPA), on bladder cancer cell adhesion in vitro was investigated in this paper. TCCSUP and RT-112 bladder cancer cells were treated with VPA (0.5 or 1 mM) twice or thrice weekly for 14 days. Controls remained untreated. Tumour cell interaction with immobilized collagen was evaluated by a flow-based adhesion assay using a shear force of 2 or 4 dyne/cm(2). The effects of VPA on the integrin adhesion receptors α3, α5, β1, β3 and β4 were assessed by flow cytometry to determine integrin surface expression and by western blotting to determine the cytoplasmic integrin level. VPA of 0.5 mM and 1 mM significantly prevented binding of both RT-112 and TCCSUP cells to collagen, compared with the untreated controls. Adhesion was reduced to a higher extent when RT-112 (subjected to 2 dyne/cm(2)) or TCCSUP (subjected to 2 or 4 dyne/cm(2)) tumour cells were treated with VPA three times a week, compared to the two times a week protocol. VPA caused a significant up-regulation of the integrin α3, α5, β1, β3 and β4 subtypes on the TCCSUP cell surface membrane. In RT-112 cells, only integrin α5 was elevated on the cell surface following VPA exposure. Western blotting revealed an up-regulation of α3, α5, β3 and β4 integrins and down-regulation of the integrin β1 protein by VPA in TCCSUP. VPA also up-regulated α5 and down-regulated β1 integrin in RT-112 cells, but also reduced α3 and β3 in TCCSUP. VPA exerted adhesion-blocking properties on bladder cancer cells under physiologic flow conditions. The effects were accompanied by distinct modifications of the integrin expression profile, which differ depending on the cell lines used. Application of VPA might be an innovative option to prevent bladder cancer dissemination.
本文研究了组蛋白去乙酰化酶（HDAC）抑制剂丙戊酸（VPA）对膀胱癌细胞体外黏附的影响。TCCSUP 和 RT-112 膀胱癌细胞每周两次或三次用 VPA（0.5 或 1mM）处理 14 天。对照组未处理。使用剪切力为 2 或 4 达因/厘米 2 的基于流动的黏附测定法评估肿瘤细胞与固定化胶原蛋白的相互作用。通过流式细胞术评估 VPA 对整合素黏附受体α3、α5、β1、β3 和β4 的影响，以确定整合素表面表达，并通过 Western blot 确定细胞质整合素水平。与未处理的对照组相比，0.5mM 和 1mM 的 VPA 显著阻止了 RT-112 和 TCCSUP 细胞与胶原蛋白的结合。当 RT-112（在 2 达因/厘米 2 下）或 TCCSUP（在 2 或 4 达因/厘米 2 下）肿瘤细胞每周处理三次时，与每周两次的方案相比，黏附程度降低得更高。VPA 导致 TCCSUP 细胞表面膜上的整合素α3、α5、β1、β3 和β4 亚型显著上调。在 RT-112 细胞中，只有在 VPA 暴露后，细胞表面的整合素α5 才升高。Western blot 显示，TCCSUP 中的 VPA 上调了α3、α5、β3 和β4 整合素，并下调了β1 整合素蛋白。VPA 还上调了 RT-112 细胞中的α5 和下调了β1 整合素，但也降低了 TCCSUP 中的α3 和β3。VPA 在生理流动条件下对膀胱癌细胞具有黏附阻断作用。这些作用伴随着整合素表达谱的明显改变，这取决于所使用的细胞系而有所不同。应用 VPA 可能是预防膀胱癌扩散的一种创新选择。
