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.
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 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)
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)
Objective To approach histologically the degree of choroidal invasions of retinoblastoma and their relations with metastasis and prognosis. Methods The pathological sections of 297 enucleated eyeballs with retinoblastom from June 1985 to 1995 were reviewed under light microscope.For the sake of assessing the risk factors of the prognosis of the disease,the graduation of the choroidal invasion was in vestigated in particular,and the follow-up of this genesis were performed as well. Results According to the degree of affection of the intraocular tissues from the tumor cells especially the choroid as the crucial structure,the choroidal invasions were classified into the following 5 categories:0，prereactive phase of retinal pigment epithelium(144/297,48.48%).Ⅰ，reactive phase of retinal pigment epithelium(81/297，27.27%).Ⅱ, early phase of choroidal invasion( 29/297,9.76%).Ⅲ, middle phase of choroidal invasion(17/297,5.72%).Ⅳ， advanced phase of choroidal in vasion(26/297,8.75%).24.24% of cases were found in phases Ⅱ-Ⅳ (so called choroidal invasion).The mortality in patients with phases 0～Ⅲ was found to be 0.4% in the average follow-up period of 51.8 months,and inpatients with phase Ⅳ was found to be 12.0%. Conclusion The retinoblastoma patient with the advanced phase of choroidal invasion (choroida l invasion with great extent) had relative high metastatic rate and poor prognos is. (Chin J Ocul Fundus Dis,1999,15:88-90)
Objective To explore the expression of survivin gene in retinoblastoma (RB) and its relationship with the stages and histodifferentiation degree of RB and the expression of p53、bcl-2 proteins. Methods Expression of survivin, p53 and bcl-2 proteins in 38 RB conventional paraffin samples were detected with survivin, p53 and bcl-2 monoclonal antibodies respectively by immunohistochemical assay. The expression of survivin of normal retina in 6 control samples was observed. Results In 38 cases of RB, positive expression of survivin was found in 20 (52.6%); while none of the 6 normal retinal tissue expressed survivin, which had significant difference between the two group (P＜0.05). The positive expression of survivin did not correlate with sex of patient, disease stages and histological type (P＞0.05). In 38 RB cases, positive expression of p53 was in 25 with the rate of 65.8%, and of bcl-2 in 18 with the rate of 47.4%. The positive-expressed rates were much higher in positive-expressed p53 and bcl-2 group than those in the negative-expressed p53 and bcl-2 group(P＜0.05). Conclusion The increase of the expression of survivin implies that it may take part in the occurrence and development of RB; the interaction among survivin, p53 and bcl-2 may participate in the access and the course of RB. (Chin J Ocul Fundus Dis，2004，20：215-217)
Retinoblastoma (RB) is the most common intraocular malignant tumor in children. With advanced clinical technologies there are more and more methods available to treat retinoblastoma, and make it is possible to delivery individualized protocol combined traditional treatments with modern regimen to patients now. In order to improve the survival rate and the life quality of RB patients in China, it is very important to make a suitable system of standardized therapy based on results from developed countries and health policies of our own country.