The preparation of novel PEI cleaning metal surface for inhibiting the proliferation and migration of Eca109 tumor cells in vitro

摘要

Introduction: Esophageal cancer, the ninth most common malignancy, is the sixth cancer mortality causes , and expandable stent placement is the most commonly performed treatments for malignant dysphagia . However, the conventional stent cannot inhibit the tumour growth, due to most dip coatings of DESs are prepared with a limited dosage of the drug and a short period of drug delivery, and the exposed basements don't have the anti-tumor function .Herein, in order to combine the advantages of the immediate relief of esophageal dysphagia using stent with the longer-term benefits that are achieved through sustained and prolonged local inhibiting tumor growth, a novel PEI cleaning metal surface was prepared in vitro. Materials and methods: Polydopamine as a transitional layer was prepared on the stainless steel (SS) surface by the method of dipping in ultrasonic environment, and polyethyleneimine (PEI) was fabricated on the polydopamine modified surface for the better inhibiting tumor growth property. The morphologies and wettability of these samples were observed by SEM and the contact angle apparatus. Then, the proliferation of ECa109 cells was investigated using AO/PI reagent and CCK-8 kits, and the migration of ECa109 cells dyed with crystal violet was tested using a 24-well transwell system . Results and discussions: Fig. 1 shows the schedule of fabricating PEI coating on the 317L SS (Fig.1 A), and the results of surface morphologies (Fig.1 B) and their wettability (Fig.1 C). The morphological changes of the surfaces showed that the surface of SS was characterized by non-uniform polishing scratches. On the SS-D sample, the polishing scratches disappeared and many micron and submicron particles appeared, while no other obvious change else happened after the deposition of PEI. The wettability result indicates that SS-D-P surface is more hydrophilic than SS surface and more hydrophobic than SS-D surface. Fig. 2 shows an obvious difference of humor cells proliferation after 6 h, 1d and 3d culture on the SS, SS-D and SS-D-P surface (Fig.2 A), and the cells seeded on SS and SS-D become polygonal at 1d, while cells on SS-D-P keep spherical morphology (Fig.2 B). In addition, there are more cells adhesion on the bottom of transwell with SS than that with SS-D-P (Fig.2 C). PEI was rich in amine groups, its toxicity is believed to be due to the charge interactions between these polymers and cell membrane, but also due to the interaction with serum proteins and causing aggregation that can lead to capillary embolism . Therefore, these results demonstrated that SS-D-P could inhibit humor cell attachment, proliferation and migration by the deposition with PEI. Conclusions: In this work, the novel PEI cleaning metal surface has good property of inhibiting humor cells proliferation and migration, it has some reference value to the stent surface modification for treating malignant dysphagia in lumen cancer field of investigation.