N-cadherin is a transmembrane glycoprotein expressed by mesenchymal origin cells and is located at the adherens junctions. It regulates also cell motility and contributes to cell signaling. In previous studies, we identified that its anomalous expression in bladder carcinoma was a tumor progression marker. A pharmacological approach to inhibit N-cadherin expression or to block its function could be relevant to prevent disease progression and metastasis development. The morphological exploration of T24 invasive bladder cancer cells by atomic force microscopy (AFM) revealed a spindle-like shape with fibrous structures. By engaging force spectroscopy with AFM tip functionalized with anti-E or anti-N-cadherin antibodies, results showed that T24 cells expressed only N-cadherin as also demonstrated by Western blotting and confocal microscopy. For the first time, we demonstrated by RTqPCR and Western blotting analyses that the peroxisome proliferator-activated receptor β/δ (PPARβ/δ) agonist GW501516 significantly decreased N-cadherin expression in T24 cells. Moreover, high non-cytotoxic doses of GW501516 inhibited confluent T24 cell wound healing closure. By using AFM, a more sensitive nanoanalytical method, we showed that the treatment modified the cellular morphology and diminished N-cadherin cell surface coverage through the decreasing of these adhesion molecule-mediated interaction forces. We observed a greater decrease of N-cadherin upon GW501516 exposure with AFM than that detected with molecular biology techniques. AFM was a complementary tool to biochemical techniques to perform measurements on living cells at the nanometer resolution level. Taken together, our data suggest that GW501516 could be an interesting therapeutic strategy to avoid bladder cancer cell spreading through N-cadherin decrease.

N-钙粘蛋白是一种由间充质来源细胞表达的跨膜糖蛋白，位于粘附连接处。它还调节细胞运动并有助于细胞信号传导。在之前的研究中，我们发现其在膀胱癌中的异常表达是肿瘤进展的标志物。抑制 N-钙粘蛋白表达或阻断其功能的药理学方法可能与预防疾病进展和转移发展相关。通过原子力显微镜 (AFM) 对 T24 浸润性膀胱癌细胞进行形态学探索，发现具有纤维结构的纺锤状形状。通过将力谱与抗 E 或抗 N-钙粘蛋白抗体功能化的 AFM 尖端结合，结果表明 T24 细胞仅表达 N-钙粘蛋白，蛋白质印迹和共聚焦显微镜也证明了这一点。我们首次通过 RTqPCR 和蛋白质印迹分析证明，过氧化物酶体增殖物激活受体 β/δ (PPARβ/δ) 激动剂 GW501516 显着降低 T24 细胞中 N-钙粘蛋白的表达。此外，高非细胞毒性剂量的 GW501516 抑制汇合 T24 细胞伤口愈合闭合。通过使用 AFM（一种更灵敏的纳米分析方法），我们发现该处理通过减少这些粘附分子介导的相互作用力来改变细胞形态并减少 N-钙粘蛋白细胞表面覆盖。我们观察到，与分子生物学技术检测到的相比，使用 AFM 暴露 GW501516 后，N-钙粘蛋白的减少幅度更大。AFM 是生化技术的补充工具，可在纳米分辨率水平上对活细胞进行测量。综上所述，我们的数据表明 GW501516 可能是一种有趣的治疗策略，可以通过 N-钙粘蛋白减少来避免膀胱癌细胞扩散。