E-cadherin and ß-catenin expression in sebaceous eyelid adenocarcinomas.

BACKGROUND: Since the E-cadherin-catenin complex is of importance in the cancerogenesis of epithelial tumors, we examined the expression of E-cadherin and ß-catenin in sebaceous adenocarcinomas of the eyelid and correlated the results with clinicopathological parameters. METHODS: The study included histological specimen of 32 patients with sebaceous adenocarcinomas of the eyelid. The expression of E-cadherin, ß-catenin, and Ki-67 nuclear antigen was analyzed by immunohistochemistry. RESULTS: The membranous expression of E-cadherin and of ß-catenin was reduced in 17 (53%) patients and 18 (56%) patients, respectively, while elevated cytoplasmic levels and a nuclear accumulation of ß-catenin were found in 27 (84%) and six (19%) patients, respectively. The low expression of membranous ß-catenin was associated with a high degree of tumor infiltration (p = 0.02), high amount of inflammation (p = 0.01), and high degree of poor tumor differentiation (p < 0.001). In a similar manner, a low membranous E-cadherin expression in tumors was significantly associated with poor tumor differentiation (p = 0.001) and high tumor cell proliferation rate (p = 0.004). The Ki-67 proliferation index was significantly higher in the group with low membranous E-cadherin expression than in the group with high membranous E-cadherin expression (62.3 ± 20.8 versus 42.1 ± 15.3; p = 0.004). The membranous E-cadherin expression and the membranous ß-catenin expression were significantly associated with each other (Fisher's exact probability test, p = 0.03). CONCLUSIONS: Sebaceous eyelid adenocarcinomas showed a decrease in the membranous expression of E-cadherin and of ß-catenin. These changes were associated with poor tumor differentiation and an increase in the tumor infiltration and inflammation, pointing at a potential role of a low E-cadherin and low ß-catenin expression for poor prognosis of sebaceous eyelid adenocarcinomas. Correspondingly, the cell proliferation index and the expression of E-cadherin were inversely correlated with each other. The findings suggest that the immunohistochemical detection of a low E-cadherin and low ß-catenin expression may help in the examination and staging of sebaceous eyelid adenocarcinomas.

Delay in the diagnosis of retinoblastoma in China.

PURPOSE: Retinoblastoma is the most frequent primary intraocular tumour and is rapidly gaining importance in Asia. As the survival is markedly dependent on early diagnosis and as information on that is not available from East Asia, we assessed the time interval between symptoms detection and therapy of children treated in the Beijing TongRen Eye Hospital. METHODS: The retrospective study consisted of all patients who were treated in the study period from January 1987 to November 2006 in the Beijing TongRen Hospital and for whom the data on delay in diagnosis, age, clinical appearance and histological tumour features were available. RESULTS: The inclusion criteria were met by 572 patients (326 boys) with a mean age of 2.6 ± 1.8. Mean interval between first detection of symptoms and clinical diagnosis and therapy was 4.1 ± 5.9 months (range: 3-36 months). A diagnostic delay of 2 months or >6 months was found for 337 (59%) children and 98 (17%) children, respectively. Diagnostic delay was significantly (p < 0.001) the longest in the 2- to 4-year-old group (5.5 ± 7.4 months). It decreased from the study period 1987-1991 to the period 2002-2006 (p < 0.001). It was significantly associated with the clinical appearance (p = 0.001) and histological finding (p = 0.008). CONCLUSIONS: Delay in the diagnosis of retinoblastoma depended on the age of the children, study period, and clinical and histological stage. Because the prognosis is markedly influenced by tumour stage, further improvements in the alertness of parents, family doctors and paediatricians and in the medical infrastructure in China may be addressed.

Retinoblastoma in the Beijing Tongren Hospital from 1957 to 2006: clinicopathological findings.

BACKGROUND: To investigate the clinical and histopathological features of eyes enucleated due to retinoblastoma in a 50-year period in China. METHODS: The study included all eyes enucleated for retinoblastoma in the Beijing TongRen Hospital in the study period from 1957 to 2006. The clinical and histological charts, and histological slides were assessed for demographic and clinical data, and histological findings. RESULTS: The study included 1234 eyes. The mean age at the time of diagnosis (2.8±1.8 years) with a peak at 1 year of age decreased significantly (p<0.001) during the study period. Children with a unilateral retinoblastoma were significantly (p<0.001) older than children with bilateral retinoblastoma. The mean delay in the diagnosis (5.5±7.2 months) was significantly (p<0.0001) associated with the age at the time of diagnosis and significantly (p<0.0001) decreased during the study period. The presenting symptoms were leucocoria (67.2%), poor vision (10.8%), a detectable tumour mass (6.4%), red and painful eye (5.3%), strabismus (4.4%), exophathalmos (2.1%) and trauma (2.3%). Prevalence of an extraocular tumour extension decreased significantly (p<0.0001) during the study period. The frequency of a tumour invasion into the retro lamina cribrosa tissue or into the choroid decreased from 45.5% and 60.6% in the period 1956-1961 to 21.5% and 18.6%, respectively, in the period 2002-2006. CONCLUSIONS: In the last 50 years, the diagnosis of retinoblastoma in China has been improved markedly with a shorter delay in the diagnosis, an overall earlier diagnosis and a decrease in the clinical and histological stage at the time of treatment.

[Histopathological study of retrolental membranes secondary to persistent hyperplastic primary vitreous].

OBJECTIVE: To study the pathological characteristics of retrolental membranes (RLMs) secondary to persistent hyperplastic primary vitreous (PHPV), and to discuss the possible pathogenesis of PHPV. METHODS: Experimental study. Six RLMs obtained from six patients with PHPV during vitrectomy were examined by light microscopy (HE & PAS staining). All of them were observed with proliferating cell nuclear antigen (PCNA) immunostaining, together with collagen I, factor VIII related antigen, smooth muscle actin (SMA), epithelial membrane antigen (EMA), neuron specific enolase (NSE) and glial fibrillary acidic protein (GFAP) staining. Apoptosis were detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL). RESULTS: Light microscopy showed that the RLM was a dense connective tissue with numerous inflammatory cells including mast cells and lymphocytes. PAS staining showed that RLMs contained a larger amount of polysaccharides. Histopathology and immunohistochemistry showed that there were vascular channels, smooth muscle cells, nervous cells and epithelial cells scattered in RLMs. Collagen I was the main component of RLMs. PCNA-positive nuclei were widely found in RLMs. TUNEL-positive nuclei were also found in all RLMs, as well as in the posterior subcapsular epithelial cells of lens. CONCLUSIONS: The cell types of RLMs secondary to PHPV are similar to those of the primary vitreous. It is possible that the mechanism of the progression of RLMs is the over-development and incomplete regression of the retrolental vascular system. Inflammation may play an important role in the regression of RLMs.

Central corneal thickness, lamina cribrosa and peripapillary scleral histomorphometry in non-glaucomatous Chinese eyes.

BACKGROUND: To examine a potential correlation between a thin cornea, a thin lamina cribrosa and a thin peripapillary sclera in normal eyes of Chinese, as surrogate for a presumed association between a thin cornea and an increased glaucoma susceptibility. METHODS: The histomorphometric study included 55 non-glaucomatous globes (55 patients; mean age: 41.6 ± 13.6 years) enucleated due to a malignant choroidal melanoma without involvement of the optic nerve or trabecular meshwork. The axial length ranged between 21 and 27 mm. Histological sections through the pupil and the optic disc were morphometrically evaluated. We measured the thickness of the central cornea, central and peripheral lamina cribrosa, and peripapillary sclera. RESULTS: The mean central corneal thickness (500 ± 68 µm) was statistically not significantly associated with the thickness of the central lamina cribrosa (207 ± 60 µm) (P = 0.62), peripheral lamina cribrosa (P = 0.61), peripapillary sclera close to the optic nerve canal (P = 0.18), peripapillary sclera just outside of the optic nerve meninges (P = 0.11), nor with the shortest distance between the prelaminar space and cerebrospinal fluid space (P = 0.09). CONCLUSIONS: In Chinese, central corneal thickness is not significantly correlated with the thickness of the central and peripheral lamina cribrosa and the thickness of the peripapillary sclera nor with the shortest distance between the intraocular space and the cerebrospinal fluid space. These histomorphometric data do not support a relationship between central corneal thickness and thickness of structures of the optic nerve head, and thus do not support an association between a thin cornea and increased structural glaucoma susceptibility.

Epithelial tumors of the lacrimal gland in the Chinese: a clinicopathologic study of 298 patients.

OBJECTIVE: To examine the clinicopathologic characteristics and clinical features of epithelial tumors of lacrimal gland in China. METHODS: The retrospective case series study included all 298 patients of epithelial lacrimal gland tumors which had been collected in the ophthalmic pathologic laboratory of the Tongren Hospital Beijing in the study period from 1961 to 2005. RESULTS: Pleomorphic adenomas were the most common tumors (n = 213 (72%)), followed by adenoid cystic carcinoma (n = 58 (20%)), pleomorphic adenocarcinoma (n = 13 (4%)), primary adenocarcinoma (n = 8 (3%)) and other tumors (n = 6 (2%)). The most frequent symptoms and clinical signs were restrictions of the lid or eye motility (121 patients; 41%), any other kind of lid involvement (71 patients; 24%), swelling (57 patients; 19%), pain (57 patients; 8%), and decrease in vision (15 patients; 5%). A restriction of the eye motility was noted for 61 patients (21%), due to an involvement of the extraocular muscles with the tumor and due to a tumor-induced displacement of the globe. Apart from the duration of symptoms, the tumor types did not vary significantly in age, gender, and laterality. CONCLUSIONS: Based on the archives of the Beijing Tongren ophthalmo-pathological laboratory, the most common epithelial tumors of the lacrimal gland in mainland China were pleomorphic adenomas, followed by adenoid cystic carcinoma. The spectrum and clinical signs of epithelial lacrimal gland tumors did not differ markedly between Chinese patients and Caucasian patients.

[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.

Lamina cribrosa and peripapillary sclera histomorphometry in normal and advanced glaucomatous Chinese eyes with various axial length.

PURPOSE: To measure laminar and peripapillary scleral architecture in normal and glaucomatous Chinese eyes with normal and those with elongated axial length. METHODS: The histomorphometric investigation included a normal group (nonaxially elongated eyes) of 40 human globes (40 patients; mean age, 41.3 +/- 13.4 years; range,15-68) enucleated because of malignant choroidal melanoma, a glaucomatous group (non-axially elongated eyes) of 55 eyes (55 patients; age, 43.3 +/- 20.3 years; range, 12-88) enucleated because of painful secondary angle-closure glaucoma, and a group of 26 glaucomatous globes (glaucomatous elongated axial length group; 26 patients; age, 29.0 +/- 14.4 years; range, 12-60) with an axial length > 27.5 mm. Anterior-posterior histologic sections were morphometrically evaluated. RESULTS: The lamina cribrosa was significantly (P < 0.001) thicker in the normal group than in the glaucomatous group, in which it was significantly (P < 0.001) thicker than in the glaucomatous elongated-length group. Lamina cribrosa thickness decreased significantly with increasing axial length (P < 0.001) and presence of glaucoma (P < 0.001). Peripapillary scleral thickness close to the optic nerve scleral canal and just outside of the optic nerve meninges decreased significantly with increasing axial length (P = 0.04 and P = 0.02, respectively). Peripapillary scleral thickness did not vary significantly between the glaucomatous group and the normal group. The distance between the intraocular space and cerebrospinal fluid space was (P < 0.001) shorter in the two glaucomatous groups than in the normal group. CONCLUSIONS: Lamina cribrosa thickness and peripapillary sclera thickness decreased significantly with axial length, in addition to a glaucoma-related thinning of the lamina cribrosa. In non-axially elongated eyes, the peripapillary sclera thickness did not vary significantly between glaucomatous eyes and normal eyes.

Molecular regulation of vasculogenic mimicry in human uveal melanoma cells: role of helix-loop-helix Id2 (inhibitor of DNA binding 2).

BACKGROUND: Vasculogenic mimicry (VM) is a tumor angiogenesis process in which highly aggressive melanoma cells form patterned, tubular networks in an in vitro, three-dimensional culture that mimics vasculogenic networks formed by endothelial cells. These cells also express endothelial cell-associated genes such as vascular endothelial-cadherin (VE-cadherin) and are correlated with poor clinical prognosis in patients. However, the molecular underpinnings of this phenomenon remain elusive. METHODS: Three-dimensional cultures of highly and poorly aggressive uveal melanoma cells were observed by inverted light microscope and scanning electronic microscope for VM. RNAi (RNA interference) technology was used to examine whether inhibitor of DNA binding 2 (Id2) was involved in the uveal melanoma vasculogenic mimicry. Western blot analysis showed changes of Id2 and VE-cadherin expression in highly and poorly aggressive melanoma cells in vitro. Migration analysis of highly and poorly aggressive uveal melanoma cells in vitro illuminated the role of Id2 in tumor cells migration. RESULTS: We show here that a transient knockdown of Id2 by RNA interference abrogates VM and VE-cadherin expression in highly aggressive uveal melanoma cells. Furthermore, inhibition of Id2 changes cellular stability and creates a more dynamic condition. Transfected cells also migrate better than untransfected cells. CONCLUSIONS: This study shows that Id2 is an important regulator of VM. Specifically, Id2 affects VE-cadherin expression, and is critical for the formation of vasculogenic-like networks.

[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.

[Photodynamic therapy of pigmented choroidal melanomas in rabbits using hematoporphyrin monomethyl ether].

OBJECTIVE: The purpose is to determine the effectiveness of photodynamic therapy of experimental choroidal melanoma in rabbits using hematoporphyrin monomethyl ether (HMME). METHODS: Pigmented choroidal melanomas were established in 46 New Zealand albino rabbit eyes. The animals were treated with daily injection of cyclosporine A. The tumors were followed up with funduscopic examination and ultrasonography until they were 1.5 to 4.6 mm in height. Then the rabbits were divided randomly into two groups. In the treatment group, 41 rabbits were injected intravenously with hematoporphyrin monomethyl ether (HMME, 10 mg/kg). 3 hours later, the tumors were irradiated at 630 nm through an He-Ne laser at estimated total light doses of 60 approximately 150 J/cm(2). Control animals (5 rabbit eyes) were treated with light only (2 rabbit eyes), photosensitizer only (2 rabbit eyes), or observation only (1 rabbit eyes). Each animal then was followed up for 4 to 5 weeks with indirect ophthalmoscopy, ultrasonography, and fundus photography (16 rabbit eyes among the treatment group were extirpated for pathologic examination 24 hours or 1 week after the treatment). In the end, all the rabbits were sacrificed and the pathologic examinations were performed. RESULTS: With the fluences of >or= 70 J/cm(2), all the tumors regressed evidently. With the fluence of 60 J/cm(2), not all the animals showed complete tumor arrest. In the control group, all the tumors showed continuous growth and filled most of the vitreous cavity in 2 to 3 weeks. CONCLUSION: The photodynamic therapy with homemade photosensitizer HMME may have a role in the treatment of pigmented choroidal melanomas.

Intraocular extension of conjunctival squamous cell carcinoma.

Conjunctival squamous carcinoma, which is regarded as a low-grade malignancy, usually originates at the limbus. Most cases remain superficial to the sclera. Intraocular invasion is rarely reported. We describe a woman misdiagnosed as conjunctivitis and pterygium before a clinical diagnosis of conjunctival squamous cell carcinoma. The diagnosis was made by histopathological examination of the biopsy specimen. Examination revealed an elevated mass on the nasal limbus extending intraocularly. White flaky mass occupied approximately 3/7 space of the anterior chamber. Exenteration was performed for control of local lesion. Histopathologic analysis confirmed that intraocular involvement occurs through the emissary vessels near the area of limbus. The case highlights the need for accurate diagnosis and prompt intervention. A brief review of the clinical and histopathologic features of conjunctival squamous cell carcinoma is also presented.

[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.

Correlation of the expression of telomerase RNA with risk factors for recurrence of sebaceous gland carcinoma.

AIMS: To investigate the expression of human telomerase gene RNA (hTR) and human telomerase reverse transcriptase (hTRT) in eyelid sebaceous gland carcinoma and to evaluate risk factors for sebaceous carcinoma recurrence. METHODS: The expression patterns of hTR and hTRT were detected by in situ hybridization (ISH) in paraffin-embedded samples of 55 eyelid sebaceous gland carcinoma, 12 chalazia, and four sebaceous adenoma. The proliferation index (PI) of sebaceous gland carcinoma was determined by Ki-67 immunolabeling and the results were compared with the expression of hTR and hTRT. Several factors for recurrence of sebaceous gland carcinoma were evaluated by statistical analysis. RESULTS: Expression of hTR and hTRT was present mainly in the sebaceous gland carcinoma tissues and not in adjacent tissues of carcinoma, chalazia, and sebaceous adenoma. The prevalence of hTR, hTRT, and Ki-67 expression in 55 sebaceous carcinoma samples were 84.45%, 58.1%, and 78.18%, respectively. hTR expression was highly associated with the degree of carcinoma differentiation (P<0.001) and hTRT expression was correlated with the proliferation index as determined by Ki-67 staining (P<0.005). There was a correlation between the recurrence of sebaceous gland carcinoma and the patient's onset age (OR=0.914, P<0.05), as well as the time to first treatment (OR=1.163, P<0.01). CONCLUSIONS: Telomerase may play an important role in the carcinogenesis of sebaceous gland carcinoma, and expression of hTR and hTRT combined with other features of sebaceous gland carcinoma may be helpful for the diagnosis and evaluation of clinical prognosis. Risk factors for recurrence of sebaceous gland carcinoma are patients' onset age and the time to first treatment.

[Clinical and pathological features of 112 cases with ocular adnexal lymphoproliferative lesions].

OBJECTIVE: To investigate the histopathological classification and clinical features of ocular adnexal lymphoproliferative lesions. METHODS: The clinical, histomorphological and immuno-histochemical features of 112 cases of ocular adnexal lymphoproliferative lesions (116 paraffin specimens) were studied retrospectively. The lesions were classified according to the World Health Organization classification of tumors of haematopoietic and lymphoid tissues (2001). RESULTS: This group of patients' ages averaged at 49. The mean duration between the onset of the symptoms and the time of presentation was 22 months. Sixteen patients (14.3%) had bilateral lesions. Proptosis or local orbital mass was presented in 69 cases (61.6%). Reactive lymphoid hyperplasia was diagnosed in 11 cases (9.8%) and atypical lymphoid hyperplasia in 10 cases (8.9%). The rest 91 cases (81.3%) were diagnosed as lymphoma, among which 74 cases (81.3%) were extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT-EMZL). CONCLUSIONS: MALT-EMZL is the most frequent type of ocular lymphoproliferative lesions in ocular adnexa. The ocular adnexal lymphoproliferative lesions show an indolent course clinically, tending to affect the old. Bilateral case is not uncommon.

[Clinical and pathological features of 273 cases of lacrimal epithelial tumors].

OBJECTIVE: A retrospective study of histopathological and clinical aspects of 261 cases of lacrimal tumors (273 paraffin specimens) from Ophthalmic Pathology Laboratory, Beijing Tongren Hospital (Dec. 1961 to Jun. 2002) was performed to investigate the pathological classification and clinical features of these tumors. METHODS: Clinical features were analyzed from 261 patients of lacrimal tumors, including patient's history, age, gender, laterality, visual acuity, ultrasound B scan, X-ray, CT, MRI, pre- and post-operation condition, follow-up data and others. These data were compared with the pathological features. RESULTS: Pleomorphic adenoma was the most common tumor in epithelial tumors of lacrimal gland, followed by adenoid cystic carcinoma, pleomorphic adenocarcinoma and adenocarcinoma. Recurrence was observed in 12 cases. The recurrence rate is 4.6%. Four cases was dead, the mortality was 1.5%. CONCLUSION: Pleomorphic adenoma shows a low mortality and a relatively high recurrence rate. The main treatment for pleomorphic adenoma is surgical treatment. It is important to have a correct clinical diagnosis, to select the proper surgical method, drug treatment and postoperative management based on the pathological diagnosis, which can result in a decrease of recurrence rate.

[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.

Telomerase expression in sebaceous carcinoma of the eyelid.

BACKGROUND: In humans telomerase is expressed in most cancers and immortal cell lines, and activation of telomerase may play important roles in tumorigenesis and immortalization. This study was to investigate the roles of telomerase activity (TA) and human telomerase RNA (hTR) in sebaceous carcinoma of the eyelid. METHODS: The telomerase repeated amplification protocol (TRAP) was used to demonstrate telomerase activity in 12 cases of sebaceous carcinoma of the eyelid. In situ hybridization (ISH) was used to demonstrate the expression of hTR in 55 cases of paraffin-embedded sebaceous carcinoma of the eyelid, and the results were compared with the proliferative index determined by Mib-1 immuno-labeling, histological patterns and recurrence of the tumor. RESULTS: Different telomerase activity was shown in the 12 cases of sebaceous carcinoma of the eyelid. The positive expression of hTR was 85.5% (47/55) in tumor cells, but not in the adjacent tissues. The positive expression of hTR was correlated with the proliferative activity (as assessed by Mib-1 immunolabelling, r = 0.942, P < 0.001) and the differentiation of sebaceous carcinoma of the eyelid (chi(2) = 17.621, P < 0.001), but not significantly related to tumor recurrence. The level of hTR expression increased with the decrease of differentiation of sebaceous carcinoma of the eyelid. CONCLUSIONS: The results suggest that the up-regulation of telomerase expression plays some roles in tarsal gland carcinogenesis, and the expression of hTR is a useful marker for malignant degree of sebaceous carcinoma of the eyelid.