Anti-oral cancer strategy by means of inhibition of cellular adhesion to extracellula matrices

我们分析了在口腔癌细胞与细胞外基质黏附受到抑制的情况下的抗癌作用。为此，苏拉明被用于抑制口腔癌细胞的黏附，如人涎腺腺样囊性癌的ACC3细胞。已知的ACC3细胞生物合成大量的细胞外基质(ECM)分子，特别是基底膜相关分子，如硫酸乙酰肝素蛋白多糖、HSPG/perlecan和纤维连接蛋白。当ACCE细胞在100um苏拉明的存在下培养时，ACC3细胞向培养液中分泌ECM分子的能力增强。加入200fm苏拉明后，ACC3细胞在培养皿上的贴壁率显著降低。在整合素的细胞外基质识别位点苏拉明和RGD肽的存在下，Atachme…NT越多，抑制作用就越强两倍。因此，苏拉明可影响整体依赖的细胞黏附。在苏拉明存在下培养的第7天，ECM分子更明显地进入ACC3细胞的培养液中。免疫荧光显示ECM分子和整合素定位于细胞质内，而不定位于细胞外间隙或细胞表面。免疫沉淀和脉冲追逐实验表明，苏拉明抑制了与整合素a5共沉淀的未知分子的生物合成。免疫印迹实验表明，该120 kDa分子为粘着斑激酶(FAK)，参与整合素的磷酸化。结果表明，苏拉明抑制ACC3细胞FAK的表达，导致整合素在细胞黏附中发挥作用，提示抑制细胞表面ECM分子受体可能是抑制口腔癌细胞生长的策略之一。较少

We have analyzed anti-cancer effect in a situation in which adhesion of oral carcinoma cells to extracellular matrices is inhibited. To this end, suramin, a polysulfonated naphthylurea, which has been used as an anti-trypanosoma reagent but has also known as an inhibitor of lysosomal heparanase, was used for inhibition of adhesion of oral carcinoma cells, such as ACC3 cells of human salivary adenoid cystic carcinoma origin.ACC3 cells have been known to biosynthesize excessive amounts of extracellular matrix (ECM) molecules, especially basement membrane-associated molecules, such as heparan sulfate proteoglycan, HSPG/perlecan, and fibronectin. When ACCE cess were cultivated in the presence of 100 ;uM suramin, secretion of ECM molecules by ACC3 cells into the culture medium was enhanced. When 200 fM suramin was added, attachment of ACC3 cells to culture dishes reduced significantly. In the presence of suramin and RGD peptides, which are an ECM recoginition site of integrins, the attachme … More nt was two times more inhibited. Thus, it was suggested that suramin affected integrih-dependent cell adhesion. By day 7 of culture in the presence of suramin, ECM molecules were shed more prominently into the culture medium of ACC3 cells. Immunofluorescence showed that ECM molecules and integrins were localized within the cytoplasm but not in the extracellular space or in the cell surface. These results indicated suramin inhibited cell membrane assembly of integrin and consequently trapping of ECM molecules by cell surface integrins.Immunoprecipitation and pulse-chase experi-ments showed that suramin inhibited biosynthesis of an unknown molecule with Mr. 120 kDa, which was co-precipitated with integrin a5. Immunoblotting experiments showed that the 120 kDa molecule was focal adhesion kinase (FAK), which functions in phospholylation of integrins. The results indicated that suramin inhibit FAK expression of ACC3 cells, which resulted in integrin function in cellular attachment.These results clearly indicate that the inhibition of cell surface receptors for ECM molecules can be one of the strategies for suppression of oral carcinoma cell growth. Less