ABSTRACT
Eyes are important human organs, and retinal degenerative diseases can cause irreversible blindness. Up to date, cell transplantation is an important method for the treatment of degenerative eye diseases. Because the number of adult eye stem cells is rather limited,it is still very difficult to activate endogenous adult stem cells as a way to treat degenerative eye diseases. Therefore,photoreceptor cells ( photoreceptor) and retinal pigment epithelium (RPE) cells generated from pluripotent stem cells include embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) can be an effective source of cells for transplantation. This article described the major types of retinal degenerative diseases including retinitis pigmentosa ( RP) and age-related macular degeneration (AMD) by focusing on their pathological process and development of stem cell transplantation. We reviewed the related stem cell therapies and research status of two different vulnerable cells, RPE and photoreceptor cell in degenerative ophthalmopathy. We also discussed the value and limitations of cell transplantation therapy and the prospect of future treatment.
ABSTRACT
AIM: To study the effects of disulfiram/copper complex (DSF/Cu) on ultrastructures and mechan-ical properties of human breast cancer and normal breast epithelial cells by atomic force microscopy (AFM) based on the nanoscale resolution and piconewton force measurement level.METHODS: The change of cell cycle and apoptotic rate of MCF-7 cells and MCF-10A cells induced by DSF/Cu were compared by flow cytometry.The cell surface morphology, ultra-structure, height, width and roughness were detected by AFM.The effects of DSF/Cu on the hardness (Young’s modu-lus) of the 2 kinds of cells were determined by AFM with indentation technique.RESULTS: DSF/Cu significantly in-duced apoptosis of the MCF-7 cells in a dose-dependent manner, whereas had little effect on the MCF-10A cells.The cell cycle analysis showed that DSF/Cu induced G2 /M arrest in the MCF-7 cells, but led to G0 /G1 arrest in the MCF-10A cells.The AFM images showed that the MCF-7 cells shrank and showed smaller and smoother morphology, and the filopo-dia were retracted obviously, even some became into lamellipodia, or disappeared completely after treated with DSF/Cu at concentrations of 400 and 800 nmol/L.The quantitative analysis indicated that the MCF-7 cells showed smaller width and larger height, and the root mean square roughness and average roughness were decreased significantly in a dose-dependent manner after treated with DSF/Cu at concentrations of 400 and 800 nmol/L.However, little effect in the MCF-10A cells was observed.The biomechanics test at a single cell level demonstrated that the Young’s modulus of the MCF-7 cells and MCF-10A cells were both increased, yet the proportion increased in the MCF-7 cells was much higher than that in the MCF-10A cells after treated with DSF/Cu at concentrations of 400 and 800 nmol/L.CONCLUSION: DSF/Cu has strong antitumor effect on breast cancer with high efficiency and low toxicity by changing the properties of the biomechanics specifically.
ABSTRACT
Aim To study the mechanism of DSF-Cu induced apoptosis of human nasopharyngeal carcinoma CNE-2 Z cells by affecting the function of mitochondria and cytoskeleton. Methods The cell cycle,the rate of apotosis,the levels of intracellular ROS and MMP in CNE-2 Z cells were tested by flow cytometry after trea-ted with different concentration of DSF-Cu. The chan-ges of the cell surface morphology, ultrastructure, cell height, width and roughness were detected by AFM. The distribution and reorganization of cytoskeleton F-actin were observed by Laser scanning confocal micro-scope. Results Cells were incubated with different concentration of DSF-Cu ( 0 ~200 nmol · L-1 ) for 24 h, the apoptotic ratio increased significantly and the treatment of DSF-Cu resulted in a concentration-de-pendent accumulation of CNE-2Z cells in G2/M phase. Furthermore,the treatment of DSF-Cu was able to in-crease the production of intracellular ROS and decrease the MMP in CNE-2Z cells. In addition,AFM imaging showed that compared to the control group,with the in-crease of DSF-Cu concentration,the CNE-2Z cells be-came smaller, cytoplasm condensed, the height in-creased,and the surface roughness reduced. Moreover, the filopodia became shorter, shrinked and even com-pletely destroyed after treated with different concentra-tion of DSF-Cu. At last,the LSCM image showed that the fluorescence intensity of F-actin networks was de-creased, then the structure was rearranged and de-stroyed obviously by treated with DSF-Cu. Conclusion DSF-Cu can induce apoptosis and arrest cell cycle at G2/M phase in CNE-2Z cell through a mitochondria-dependent pathway. Above findings highlight the appli-cations of AFM at the single cell level for the investiga-tion of antineoplastic drug in nasopharyngeal carcinoma therapy.