[Studies on multidrug resistance associated protein in retinoblastoma].

OBJECTIVE: To detect the expression of P-glycoprotein (P-gp), lung resistance associated protein (LRP) and multidrug resistance associated protein (MRP) in retinoblastoma (Rb), to analyze the relationship between the expression of multidrug resistant (MDR) markers with clinic-pathological factors, the correlations among these three markers, and to study the possible mechanism of multidrug resistance in Rb. METHODS: It was an experimental study. Seventy-five cases of Rb were studied with immunohistochemical methods using antibodies against P-gp, LRP and MRP. The relationship between their expression and the clinicopathological features of Rb, and the relationship between the expression of these three markers were investigated. RESULTS: The positive expression rates of P-gp, LRP and MRP were 64.0%, 25.3%, 36.0% in Rb, respectively. The co-expression rates of P-gp and LRP, P-gp and MRP, LRP and MRP were 18.7%, 32.0%, 20.0%, respectively. All tested proteins showed significant correlation to the differentiation of the tumor (P = 0.006, 0.000, 0.000, respectively), but no correlation was found between the expression of these markers and the age or sex of the patients. Significant positive correlations were observed between P-gp and MRP expression (P = 0.001), and between LRP and MRP expression (P = 0.000). CONCLUSIONS: The intrinsic multidrug resistance of Rb involves the combined effects of P-gp, LRP and MRP.

Eyelid neoplasms in the Beijing Tongren Eye Centre between 1997 and 2006.

BACKGROUND AND OBJECTIVE: To examine the spectrum of eyelid neoplastic specimens obtained at the Beijing Tongren Eye Centre between 1997 and 2006. PATIENTS AND METHODS: A total of 2,639 eyelid neoplasms were included in the study. RESULTS: Of the 2,639 eyelid specimens, 2,276 (86.2%) were benign and 363 (13.8%) were malignant. The most common benign lesions were inflammatory lesions, melanocytic nevi, papillomas, dermoid and epidermoid cysts, and epithelial cysts. The most common malignant or semi-malignant tumors were basal cell carcinomas, sebaceous gland carcinomas, lymphomas, squamous cell carcinomas, and malignant melanomas. The mean age at diagnosis was 41 years for benign lesions and 60 years for malignant tumors. There was no significant gender predilection among the five major non-benign eyelid tumors. CONCLUSION: At the BeijingTongren Eye Centre between 1997 and 2006, the predominant non-benign eyelid tumors were basal cell carcinoma and sebaceous gland carcinoma, followed by lymphoma. The non-benign lesions occurred predominantly in elderly patients who were 60 years of age and older.

[Clinical and pathological analysis of 2639 cases of eyelid tumors].

OBJECTIVE: To describe the histopathologic spectrum and patient characteristics of eyelid tumors in Beijing Tongren Hospital. METHODS: It was a claims database analysis. A total of 2639 eyelid tumors verified histopathologically from January 1997 to December 2006 were included in the study. RESULTS: Of the 2639 eyelid tumors, the 5 most common eyelid benign lesions were inflammatory lesion, melanocytic nevus, papilloma, dermoid cyst and epidermoid cyst, and epithelial cyst. The 5 leading eyelid malignant tumors were basal cell carcinoma, sebaceous gland carcinoma, lymphoma, squamous cell carcinoma and melanoma. The mean age at diagnosis was 61 years for basal cell carcinoma and sebaceous gland carcinoma, 57 years and 52 years for squamous cell carcinoma and melanoma, respectively, and 48 years for lymphoma. There was no significant sex predilection in basal cell carcinoma and sebaceous gland carcinoma. Melanoma and lymphoma occurred more commonly in women, whereas squamous cell carcinoma occurred more commonly in men. CONCLUSIONS: Basal cell carcinoma and sebaceous gland carcinoma were the most common malignant eyelid tumors, and lymphoma ranked third and had an increasing trend. The malignant tumors occurred predominantly in the elderly of 60 years and above.

[Study on the risk factors for optic nerve invasion in 381 cases of retinoblastoma].

OBJECTIVE: To investigate the clinical and pathologic outcomes of a large group of retinoblastoma (RB) cases to ascertain the risk factors of RB optic nerve invasion. METHODS: In this paper, we summarized the clinical and pathologic data of 381 retinoblastoma cases in Beijing Tongren Hospital observed from 1990 to 2002. Statistical analyses were performed on the sex, age, unilateral or bilateral cases, length of symptoms, clinical situation, stage, histological type and the degree of optic nerve invasion. RESULTS: The degree of RB optic nerve invasion was closely correlated to clinical stage and tumor differentiation. CONCLUSION: Avoiding the risk factors of RB optic nerve invasion is very important for the prognosis of RB.

[The effects of matrine on cell proliferation and telomerase activity in retinoblastoma cells in vitro].

OBJECTIVE: To evaluate the effects of matrine on cell proliferation and telomerase activity in retinoblastoma cells in vitro. METHODS: HXO-Rb44 cells were treated with 0.1 to 3.2 mmol/L matrine for 24 h, then cell viability was measured by MTT assay. Apoptosis rates were evaluated by flow cytometry and TUNEL assay after the cells were treated for various durations. The telomerase activity were measured by telomeric repeat amplification protocol. RESULTS: MA inhibited the growth of HXO-Rb44 cells. Ma induced the apoptosis and down-regulated the telomerase activity of HXO-Rb44 cells, which were time dependent. There was a positive correlation between the telomerase activity and the apoptosis (r = -0.961, P < 0.01). CONCLUSIONS: Ma can induce the apoptosis and down-regulate the telomerase activity of retinoblastoma cells, which may be one of important mechanisms to inhibit the cell proliferation. It suggests that Ma may be a potent drug for the treatment of retinoblastoma.

[The study on the correlation between telomerase and histopathologic features of retinoblastoma].

OBJECTIVE: To investigate the correlation between the expression of human telomerase RNA (hTR), human telomerase reverse transcriptase (hTRT) and the proliferation and differentiation of retinoblastoma (RB). METHODS: In 37 RB specimens, the expression of hTR and hTRT was investigated with the methods of in situ hybridization (ISH). Immunohistochemical method was performed to detect the expression of proliferating cell nuclear antigen (PCNA) in RB. All data were analyzed statistically with SPSS. RESULTS: Of 37 RB specimens, positive expression of hTR and hTRT was 83.8% and 89.2%, respectively, while negative results were observed in 2 normal retina tissues. The expressions of hTR and hTRT showed a close correlation to the proliferation and differentiation of RB. Furthermore, there was a close correlation among the expression of hTR and hTRT. CONCLUSIONS: These results suggest that higher expression of hTRT and hTR may be used as new parameters for evaluating the degree of malignancy of RB. The close correlation between the expression of hTR and hTRT and proliferation and differentiation degrees of RB indicats that the expression of telomerase can influence the proliferation and differentiation of RB. Because the telomerase is presented in the Rb, therefore, modulating the telomerase activity may be used as a novel treatment for the RB.