Objective
To investigate the correlation of expression of Fas/Fas ligand (FasL) and apoptosis in retinoblastoma (RB)．
Methods
The expression and distribution of Fas/FasL were detected by using immunohistochemical staining in 32 cases of RB． Light microsc opy (32 cases), electron microscopy (4 cases) and TdT mediated biotin-d UTP nick-end labeling (TUNEL) (12 cases) were used to study apoptosis in RB．
Results
Apoptotic RB cells mostly located at RB regress area． Chromatin margination and apoptotic bodies were found in RB． TUNEL posi tive labeling cells especially located in tumor regress area． Positive immunola beling for Fas and FasL was found in all RB specimens． There was a highly signi ficant and positive correlation between the expression of Fas/FasL and apoptotic indices (AI) (Plt;0.01 or 0.001)．
Conclusion
The results suggest that apoptotic cell death is prevalent in RB and it may be one type of the most dominant cell death． Fas system may play an important role in oncogenesis and progression of RB, and the up-regulation of Fas system expression might induce RB cell apoptosis．
(Chin J Ocul Fundus Dis, 2001,17:21-23)
PURPOSE:Studying the multidrug resistance(MDR) phenotype occurring in retinoblastoma and its mechanism.
METHODS:Using the procedure of stepwise increase in drug concentrations to obtain a retinoblastoma subline which resistant to 600ng/ml vincristine (HXO-RB/VCR). Characteristics of this drug-resistant cell line were investigated by cell
counting,drugcontents determinatin,drug sensitivity evaluation and radiation sensitivity test. RESULTS:This cell line was cross-resistant to VDS,MMC VP16，ADM ,DDP,CBP,but not resistant to BCNU and 5-Fu. It was proved to be collaterally sensitive to MTX,and the response to 60Co gamma;-ray was modified slightly in HXO-RB/VCR cell line. Intracellular levels of VCR was much higher in HXO-RB44 cells than in the resistant subline. Those cross-resistances can be reversed by verapamil partly.
CONCLUSIONS:MDR and radiation resistance of retinoblastoma can be induced by exposing to VCR and reversed by verapamil partly.
（Chin J Ocul Fundus Dis,1997,13: 6-9）
Objective To observe and evaluate the short-term therapeutic effect of intravitreal injection with topotecan for refractory vitreous seeding from retinoblastoma (RB)． Methods Eleven patients (11 eyes) of RB with refractory vitreous seeding (received intravenous chemotherapy, intra-arterial chemotherapy, intravitreal melphalan, laser, cryotherapy and subsequently developed refractory viable vitreous seeds) were enrolled in this study. There were 6 males (6 eyes) and 5 females (5 eyes). The aged from 9 to 44 months, with the mean age of 26 months. According to International Intraocular Retinoblastoma Classification, 11 eyes were initially classified as group E (3 eyes), D (6 eyes), B (1 eye) or A (1 eye). All patients were received intravitreal injection with topotecan. A total of 32 intravitreal topotecan injections were performed with a mean of 2.9 injections (median 3 injections; range 2?4 injections). The mean follow-up was 10 months. The safety and effectiveness of intravitreal injection with topotecan for refractory vitreous seeding from RB were observed. Results Complete regression of vitreous seeds was achieved in 11 of 11 eyes (100%), including complete disappearance in 9 eyes and fibrosis in 2 eyes. None of the patients needed enucleation and occured ocular or systemic complications in the follow-up period. Conclusion Intravitreal injection with topotecan for refractory vitreous seeds from RB is effective and safe.
OBJECTIVE：Observing the clinical and pathological features of Coats disease. METHODS:Reviewing the clinical data and pathologic slides duly confirmed by pathology of 19 cases of Coats disease,which belonging to our college's Laboratory of Ophthalmologic Pathology from 1959 to 1994.
RESULTS: 14 males,5 females,aged 1-18 years. More boys were affected than girls in the age group under 10 and that difference between both sexes became gradually less as they grew older. The main pathologic changes were the vascular dilatation and congestion of the outer layer of the retina,the uneven thickness of the vascular walls and the proliferation of the connective tissue. Retinal protuberance was seen in most of the advanced cases.with bleeding and vascular changes on its surfaces. The main pathologic changes were the detachment of retina and the appearance of many foam cells and crystals of cholesterol in the subretnal fluid,and calcification and ossification of the outer layer of the retina were found in some cases.
CONCLUSION :Cytological examination of the subretinal fluid might be the liable method in differentiating between the Coats disease and retinoblatstoma.
（Chin J Ocul Fundus Dis,1996,12: 157-159）
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)
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.
Retinoblastoma susceptibility gene(Rb gene)is a tumor suppressor,which often deleted,mutated or inactivated in many malignant tumors.We construct an antisense Rb gene expression vector DOLRBAS and transfected it into human embryonic lung fibroblast(HEL cells)by electroporation technique.With the transient expression of antisense Rb gene the Rb protein synthesis is reduced and the growth rate of HEL cells in increased,but no coloney of HEL cells formed in soft agar.This result indicates that Rb gene can block cell division of HEL cells,but inactivation of Rb gene only is not sufficient for malignancy transformation of HEl cells. （Chin J Ocul Fundus Dis,1993,9:198-201）
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）
Objective To investigate the effect of the 8-bromum-cyclic adenosine monophosphate (8-Br-cAMP) on the telomerase activity and changes of cell cycle in retinoblastoma （RB） cells. Methods The cultured RB cells were divided into the experimental group (8-Br-cAMP) and control group. After cultured for 24, 48 and 72 hours in vitro, the telomerase activity of RB cells was detected by polymerase chain reaction enzyme-linked immunosorbent assay (PCR-ELISA) and the changes of cell cycle were detected by flow-cytometry. Results The difference of telomerase activity was significant between the experimental groups and control group (Plt;0.01). There was a negative correlation between the A value of absorbance and the time in the experimental groups (r=-0.778 9, F=33.936, Plt;0.01). The changes of the cell cycle were that the percentages increased in G1 phase and decreased in S phases. Conclusion 8-Br-cAMP may weaken telomerase activity, affect the cell cycle, and inhibit the proliferation of RB cells. (Chin J Ocul Fundus Dis，2004，20：358-360)
Objective
To probe the relationship of differentiation degree with spread or survival prognosis in retinoblastoma (RB).
Methods
Clinical data, follow up status and eyeball specimens in 156 RB cases were investigated retrospectively. The tumors were divided into differentiated and undifferentiated groups. Conditions of the tumor invasion of ocular or surrounding tissues were reviewed. The fatality rate was obtained from the follow-up materials of 82 cases of RB. The fatality rate and the invasion rate between the two types were compared statistically by Chi-square test. In addition, the relation between the tumor invasion and death ,and the average survival time for dead people after surgery were explored.
Results
Local invasion of tumor cell was found in 8 eyes among 17 eyes with differentiated RB (47.06%),and in 66 eyes among 139 eyes with undifferentiated RB (47.48%).There was no significant difference with regards to the local invasion between the two types ( The fatality rate of cases of differentiated RB was 27.27%,and 22.54% in undifferent iated RB, and there was no statistical difference between the two types .The fat ality rate for patients with orbital and scleral extension was 100%, optic nerve invasion (grade Ⅳ) was 62.50%,and uveal invasion was 22.22%.The survival time for the dead victims were from 5 months to 41 months and averaged to 21.92 months.
Conclusion
There was no significant differ ence both in survival prognosis and local invasion between the two types. The survival prognosis of metastatic RB was dependent on the degree of spread and the efforts of treatment and regardless of the types of differentiation of RB cells.
(Chin J Ocul Fundus Dis, 2001,17:18-20)
