RESUMO
Three-dimensional (3D)-printed scaffolds have great advantages for bone repair, and the combination of physical and chemical modifications of the surface can improve deficient biological properties to promote bone regeneration. In this study, a nanotopological morphology and an amino group were introduced into scaffold surfaces in sequence by alkaline solution and amination, respectively. The surface properties and the ability for osteogenic induction were investigated. The nanotopological morphology of the surface slightly enhanced the hydrophilic property of the material, while amination obviously increased the hydrophilicity of the surface. The aminated surface improved cell adhesion and proliferation, while the nanotopological morphology was able to facilitate the spread of stem cells, pseudopod extension, and osteogenic differentiation by changing the cell skeleton. The study confirmed that a nanotopological morphology and an amino group can play synergistic roles in improving the osteogenic efficiency and hydrophilicity, which was also confirmed in vivo by showing that effective surface modification of polylactic acid scaffolds enhanced high-quality bone formation, thus demonstrating great potential for clinical applications. The results indicate that scaffolds with the synergy of a nanotopological morphology and amino modification improve the osteogenic induction ability of scaffolds.
RESUMO
Malignant melanoma is an aggressive tumor with high fatality rates and poor prognosis, mainly due to the lack of efficient treatment methods. The present study investigated the potential antitumor effects of recombinant adenovirus p53 (rAd-p53) on human malignant melanoma. The optimal viral titer on a human malignant melanoma (A-375) cell line was determined for the rAd-p53 treatment. The invasive abilities, apoptosis, variations in the cell cycle, and molecular expression levels of A-375 cells were detected after infection by rAd-p53. A tumor growth curve and hematoxylin and eosin staining were carried out for experiments in nude mice. Twenty-one patients with malignant melanoma were evaluated, including 12 cases without gene therapy and nine cases with rAd-p53 gene therapy. The overall survival rate and the median survival time were analyzed between the two groups of patients. When the multiplicity of infection was 100, the cells showed the best transfection efficiency. The invasive ability, apoptosis, cycle changes of the cells, and the expression of the p53, p21, and Bax genes and proteins were significantly changed in the experimental group. In nude mice, the tumor growth curve and the tumor size in the experimental group were significantly smaller than those of the control group. Hematoxylin and eosin staining revealed tumor metastasis in the blank group and the control group but not in the experimental group. Between the two groups of patients, the median survival of the gene therapy group (38 months) was greater than that of the group without gene therapy (27 months). In this study, high expression of the p53 gene could regulate the gene expression and reduce the invasive and metastatic abilities of the tumor cells. Furthermore, rAd-p53 effectively improved the survival of patients with malignant melanoma. Therefore, rAd-p53 may be a potential treatment method for human malignant melanoma.
