Micro/nanotextured topographies (MNTs) can modulate cell-biomaterial interactions mostly by their controllable geometrics. Among them, TiO₂ nanotubes, regarded as having a highly controllable nanoscale geometry, have been extensively investigated and applied and significantly affect diameter-dependent cell biological behaviors. In this study, we used five typical MNTs decorated with TiO₂ nanotubes with diameters of 30, 50, 70, 100 and 120 nm to explore the optimal nanotube diameter for improving the biofunctional properties and to more deeply understand the underlying mechanisms by which these MNTs affect osteogenic differentiation by revealing the effect of beta1-integrin/Hedgehog-Gli1 signaling on this process. The MNTs affected MG63 osteoblast-like cell spreading, osteogenic gene expression (BMP-2, Runx2 and ALP), mineralization and ALP activity in a diameter-dependent pattern, and the optimal TiO₂ nanotube diameter of 70 nm provided the best microenvironment for osteogenic differentiation as well as beta1-integrin/Hedgehog-Gli1 signaling activation. This enhanced osteogenic differentiation by the optimal-diameter TiO₂ nanotubes of 70 nm was attenuated via suppression of the beta1-integrin/ Hedgehog-Gli1 signaling, which indicated a significant role of this pathway in mediating the diameter-dependent osteogenic differentiation promotional effect of MNTs with different TiO₂ nanotube diameters. These results might provide deeper insights into the signal transduction mechanisms by which different nanoscale geometries influence cellular functions for biomaterial modification and biofunctionalization.

微/纳米纹理拓扑结构 (MNT) 可以主要通过其可控的几何形状来调节细胞-生物材料的相互作用。其中，TiO ₂纳米管被认为具有高度可控的纳米级几何形状，已被广泛研究和应用，并显着影响直径依赖性细胞生物学行为。在这项研究中，我们使用了五种典型的用 TiO ₂装饰的 MNT直径为 30、50、70、100 和 120 nm 的纳米管，以探索改善生物功能特性的最佳纳米管直径，并通过揭示 β1-整合素/刺猬蛋白的作用更深入地了解这些 MNT 影响成骨分化的潜在机制-Gli1 在此过程中发出信号。MNTs 以直径依赖性模式影响 MG63 成骨细胞样细胞扩散、成骨基因表达（BMP-2、Runx2 和 ALP）、矿化和 ALP 活性，70 nm的最佳 TiO ₂纳米管直径为成骨细胞提供了最佳微环境。分化以及 beta1-integrin/Hedgehog-Gli1 信号激活。这种通过最佳直径的 TiO ₂增强成骨分化70 nm 的纳米管通过抑制 beta1-integrin/Hedgehog-Gli1 信号而减弱，这表明该途径在介导具有不同 TiO ₂纳米管直径的 MNT 的直径依赖性成骨分化促进作用中具有重要作用。这些结果可能对信号转导机制提供更深入的了解，不同纳米级几何形状通过该机制影响生物材料修饰和生物功能化的细胞功能。