Microparticles are small vesicles that are released by budding of the plasma membrane during cellular activation and apoptotic cell breakdown. A spectrum of cell types can release microparticles including endothelial cells, platelets, macrophages, lymphocytes and tumor cells. Biological effects of microparticles mainly include procoagulant activity, inhibition of inflammation and cancer progression. The present study shows that vitreous microparticles isolated from proliferative diabetic retinopathy (PDR) stimulated endothelial cell proliferation and increased new vessel formation, promoting the pathological neovascularization in PDR patients. Oxidative stress induces the formation of retina pigment epithelium-derived microparticles carrying membrane complement regulatory proteins, which is associated with drusen formation and age related macular degeneration. Microparticles from lymphocyte (LMP) play an important role in anti-angiogenesis by altering the gene expression pattern of angiogenesis-related factors in macrophages. Besides, LMP are important proapoptotic regulators for retinoblastoma cells through reduction of spleen tyrosine kinase expression and upregulation of the p53-p21 pathway which ultimately activates caspase-3. However, how to apply the microparticles in the prevention and treatment of retinal diseases is a major challenge, because the study of the microparticles in the fundus diseases is still limited. Further studies conducted would certainly enhance the application of microparticles in the fundus diseases.
OBJECTIVE:To investigate the cytotoxic effects of homoharringtonine(HHT) on HXO-RB44 cell line and the cell death form induced byHHT in vitro. METHODS:MTT assay was adopted to establish survival rate of the tumor cells. Agarose gel electrophores was chosen to detect the genomic DNA from the cells exposed to HHT. RESULTS:In the concentration from 10-9 to10-4 mol/L HHT powerfully inhibited the growth of the cells (P＜0.05). Regular genomic DNA fragmentation from the cells exposed to 10-6mol/L HHT for 48 hours was shown to be typical DNA ladder on agarose gelelectrophoresis. CONCLUSION :HHT can induce retinoblastoma (RB) programmed cell death (PCD),the effects of which has close correlation with incubated period and concentration of HHT.
Objective To compare the differences of chromosome aberration and Rb 1 gene mutation among 3 cloned cells of SO-Rb50 cell line of retinoblastoma. Methods 1.Three cell cloned strains named MC2, MC3, MC4 were isolated from SO-Rb50. 2. Gbanding and karyotype analysis were performed on the llth passage cells of the 3 cell strains.3.All exons and the promoter region of the Rb gene were detected by PCR-SSCP analysis in tumor cell DNA extracted from the 3 cell strains. Results 1.Both numerical and structural chromosomal aberrations could be observed in these 3 cell strains.Several kinds of structural chromosomal aberrations were observed.The chromosome aberrations in the same passage of different cell strains were different.Aberration of chromosome 13 was rare and the aberration feature was different in the 3 cell strains.Five marker chromosomes were identified.M1,t(1;1)qter-p35∷q24-ter could befound in all cell strains.Two of them M4 and M5,have not been reported in SO-Rb50 cell line previously.2.SSCP analysis of exon 24 showed that MC411 and MC3138 had abnormal band. Conclusions The characteristics of heterogeneity of the original tumor cell line SO-Rb50are still kept during a long-term culture in vitro and the cloned strains had dynamic changes during this period.Aberration of chromosome 13 is not the only cause of RB;aberration of chromosome 1,a commom event in some neoplasias as well as in SO-Rb50, plays a meaningful role in the immortalization of this cell line. (Chin J Ocul Fundus Dis, 1999, 15: 146-148)
MTT assay was presented in this paper and used in 3 cases of retinoblastoma afert enucleation to evaluate the clinical effect of different chemotherapeutic agents.The results showed that the sensitivity of anticancer agents were various in different cases of retinoblastoma.The combining treatment of tow anticacer agents together was seemingly preferable to a single use.When a single drug was chosen,it was advisable to use carboplatin,cisplatin,mitomycin C or etopside.If a combination of 2 anticancer drugs were applied,vincristin with carboplatin or cisplatin will give a better effect than others,but vincristin is not sensitive when applied alone. （Chin J Ocul Fundus Dis,1993,9:207-209）
A review of 426 patients with retinoblastoma(RB)who presented to Eye Hospital of Zhongshan Ophthalmic Center from 1966 to 1991 showed that 81(19.01%)patients were more than or equal to 5 years of age(median age 6.95 years)at the time of initial diagnosis.All patients are unilateral except 4 cases who are bilateral.The main presentations included leukocoria,exophthalmos,congertion and pain of the eye,drcreased vision,strabismus,oculare hypertension,vitreous opacity,hypopyon and hyphema,etc.Some atypical presentations in these older patients with RB were discussed and some problems that should be noticed in the diagnosis and management were presented.discussed and some problems that should be noticed in the diagnosis and management were presented. （Chin J Ocul Fundus Dis,1993,9:205-206）
Objective To observe the expression of matrix metalloproteinase（MMP-2, MMP-9 and vascular endothelial growth factor (VEGF) in retinoblastoma (RB) and its relationship with the differentiation and optic nerve infiltration of RB.Methods Forty paraffin specimens of pathological confirmed RB were studied. They were divided into differentiated group (15 cases) and undifferentiated group (25 cases) , optic nerve infiltration group（13 cases） and without optic nerve infiltration group（27 cases）. The expression of MMP-2, MMP-9 and VEGF were detected by immunohistochemistry, their relationships with the differentiation and optic nerve infiltration were also analyzed.Results The positive rate of MMP-2, MMP-9 and VEGF expression in 40 RB cases were 52.5％，57.5％ and 72.5% respectively．The expression of MMP-2, MMP-9 and VEGF in the undifferentiated group were significantly higher than those in the differentiated group (chi;2=9.037, 9.253, 8.095; P＜0.05). The expression of MMP-2, MMP-9 and VEGF in RB with optic nerve infiltration group were significantly higher than those in RB without optic nerve infiltration group (chi;2=11.045,10.243, 8.956；P＜0.05). The expression of MMP-2，MMP-9 had a positive correlation with the expression of VEGF in RB (r=0.126,0.314；P＜0.05). Conclusions MMP-2, MMP-9 and VEGF expressed in RB tumor tissues. The expression of MMP-2, MMP-9 has a positive correlation with the expression of VEGF. The levels of MMP-2, MMP-9 and VEGF expression are related to optic nerve infiltration of RB cells.
Nowadays, one of the most challenging aspects of retinoblastoma (RB) therapy is how to control the resistant or recurrent viable vitreous seeds, for which intravenous chemotherapy appears to be ineffective. Recently, intravitreal chemotherapy offers another option to control advanced stage and vitreous seeds of RB, and may be a promising new approach to RB therapy. However, intravitreal injection for RB patients raises considerable controversy due to concerns of possible extraocular extension along the injection route, and should not replace the primary standard of care for bilateral RB or group E eyes of RB. Close follow-up and further studies are needed to determine appropriate indications, to determine the effective drugs and concentrations, to optimize RB therapy protocols and to investigate the relationship between long-term efficacy and toxicities.
We have studied the radiosenstivity of retinoblastoma cell [inc: HXO Rb~4,and found that the ceil growth reduced markedly after being treated by 3GyT-ray. From both clone for mation method and MTT assay,we identify that HXO-Rb44 cell is radiosensitive to T-ray.Oxygen can increase the radiosensitivity of HXO-Rb44 cell, but decrease the repair of sublethal damage.Oxygen enchaneement ratio(OER)is 2.77~3.01. （Chin J Ocul Fundus Dis,1994,10:217-219）
ObjectiveTo investigate the expression of transcription factor SOX11 in retinoblastoma (RB) and the relation with the genes and cellular pathways.MethodsA public data set gse59983 containing the full mRNA expression profile of cancer tissues in 76 RB patients was downloaded from the GEO Database at the National Center for Biotechnology Information. According to the expression of 15 marker genes, these genes were divided into cell cycle marker genome (group 1, 26 patients), vertebral photoreceptor marker genome (group 2, 4 patients) and rod photoreceptor marker gene (group 3, 46 patients). R2 bioinformatics platform (http://r2.amc.NL) was used to analyze the gse59983 public data set. The SOX11 expression in cancer tissues of patients in 3 groups were observed and the SOX11-related genes were identified. According to the gene correlation, the clustering heat map was drawn, and the related genes and pathways of SOX11 were preliminarily analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis tool and Gene Annotation (GO) analysis method.ResultsSOX11 expression in cancer tissues of patients in group 1 was significantly higher than that of groups 2 and 3 (P＜0.001). SOX11 expression in cancer tissues of patients in group 3 was significantly higher than that in group 2 (P＜0.001). A total of 4524 genes significantly related to SOX11 expression were detected. Among them, there were 2139 positively correlated genes and 2385 negatively correlated genes. SOX11 and the 16 genes with the strongest correlation were screened and the clustering heat map was drawn. The clustering form of SOX11 and SOX11 significantly correlated genes was roughly the same as the original form. KEGG and GO analysis showed that SOX11 related genes were involved in regulating mitotic cell cycle, cell apoptosis, photoreceptor cell development, photoreceptor cell protection, etc.ConclusionThe expression of SOX11 in RB is significantly different in different types or periods. Its expression is significantly correlated with genes involved in the regulation of cell cycle.
PURPOSE: To produce monoclonal antibodies directed against tumor-associated antigens expressed of retinoblastoma-derived tissue culture cell line SO-RBS0. METHODS:Hybridization was performed and the specificity of the antibody was tested by immunofluorescent and immunohistochemical methods. RESULTS:Two hybridomas secreted specific monoclonal antibody against retinoblastoma cells were produced ,and the isotype of the monoclonal antibody was IgG2a CONCLUION:The monoclonal antibodies were specific and highly active against retinoblastoma cells and might be used as immunoconjugate.