Effect Of Microtopography Based On Al/PDMS On The Morphology Of Tumor Cells

Objective: This study aims to develop gradient micro-roughened alumina surface（Al₂O₃）modified with poly（ethylene glycol）methacrylate（POEGMA）brushes and biomimetic micro-patterned polydimethylsiloxane（micro-PDMS）and investigate the effect of the two microtopographies on the morphology of tongue squamous carcinoma cell（Tca-8113）and cervical cancer cell（HeLa and SiHa）.It provides potential applications for cancer diagnosis and treatment.Methods: Al₂O₃ was developed by electrochemical etching and anodic oxidation method,and then POEGMA brushes were grafted onto its surface by surface-initiated atom transfer radical polymerization（SI-ATRP）.Micro-PDMS was made by biomimicking the patterns of natural Trifolium and Parthenocissustricuspidata leaves using the template method.The two surface topographies were characterized by SEM.The surface chemical composition of POEGMA was determined by XPS and FTIR.The surface wettability and roughness were characterized by optical contact angle measuring device and three-dimensional surface profiler.MTT assay was used to detect cytotoxicity.The effect of POEGMA-Al₂O₃ and micro-PDMS on cell morphology of Tca-8113,HeLa and SiHa cells were observed by SEM.And the effect of micro-PDMS on cytoskeleton of He La and SiHa was evaluated by confocal laser scanning microscopy（CLSM）.Results: 1)SEM images revealed that there were step-like porous structures on Al₂O₃,surface roughness of which was between 1-12 μm.The number and depth of step-like structure increased with increasing the roughness of the surface,and the size and density of the porous structure increased corresponding to the roughness increase;Surface wettability was negatively correlated with surface roughness;XPS and FTIR spectras confirmed that POEGMA was successfully grafted onto the gradient Al₂O₃.MTT results showed that compared with POEGMA-Silicon（Si）,cell viability of Tca-8113 decreased significantly on the POEGMA-Al₂O₃;At different roughness gradient regions,cell viability dropped gradually with increasing the surface roughness.SEM images indicated that at the early stage of cell attachment on the gradient Al₂O₃,the spread of the cells decreased with the enhancement of surface roughness.The POEGMA-Al₂O₃ can promote Tca-8113 cell adhesion and spreading compared with POEGMA-Si.2)SEM images indicated that the surface topographies of micro-PDMS were remarkably complementary to the surface microstructure of original leaves.Surface wettability results showed that the micro-PDMS were endowed with hydrophobic properties of the original leaves.Surface roughness of biomimic micro-PDMS templated with Trifolium leaves is 1.6 times of parthenodssustricuspidata leaves.SEM and CLSM imaging showed that micro-PDMS have a significant influence on morphologies and features of HeLa and SiHa cells.Compared with the flat PDMS,micro-PDMS can promote cell spreading.Conclusion: Both POEGMA-Al₂O₃ and micro-PDMS were successfully fabricated.The two surface topographies can significantly affect cell adhesion and morphology of Tca-8113,HeLa and SiHa cells.