No abstract available.
Antigens, Viral, Tumor* ; Simian virus 40*

PURPOSE: To determine whether the delivery of the SV40 large T-antigen is a feasible method for transiently inducing proliferation of corneal endothelial cells, we delivered liposome-protein complex into bovine corneal endothelial cells(BCEC). METHOD: SV40 large T-antigen protein was introduced into BCEC and positive cells were identified by immunohistochemistry. Quiescent BCECs were double-labeled using BrdU as a measure of de novo DNA synthesis and the Ki-67 was detected by standard immunohistochemical methods. RESULT: The treatment of quiescent BCECs with large T antigen caused an increase in BrdU incorporation and Ki-67 expression. It was tested by time-course study. CONCLUSION: This finding suggests that liposome-mediated delivery of transforming proteins could be a method to transiently induce corneal endothelial cell proliferation.
Antigens, Viral, Tumor* ; Bromodeoxyuridine ; Cell Proliferation ; DNA ; Endothelial Cells* ; Immunohistochemistry

The coeneal endothelium is essential for the maintenance of normal corneal hydration, thickness, and transparency. However, corneal endothelial cells are incapable of significant proliferation in vivo. As we age, the density of corneal endothelial (CEN) cells gradually decreases. The goal of our study is to explore the possibility of enhancing the proliferation of corneal endothelial cells by introduction of SV 40 large T antigen, a transforming protein. To this end, introduction of protein into CEN cells was assessed by liposome assisted beta-galactosidase transfection in vivo, ex vivo, and in vivo. In all cases, cells treated with liposome-protein complex have shown dramatic blue stain in beta-galactosidase activity staining. This result convinced us that we could artificially introduce a foreign protein into a cell. To ascertain where SV 40 large T antigen is localized in the cell, purified SV 40 large T antigen was transfected into the cells using liposome and its presence was determined immunohistochemically. We show that the liposome delivered SV 40 large is localized in the nucleus and mitotic figures which may suggest its functional activity.
Antigens, Viral, Tumor* ; beta-Galactosidase ; Endothelial Cells* ; Endothelium ; Liposomes ; Transfection*

BACKGROUND: Conditionally immortalized hepatocytes (CIH) can be cultured almost indefinitely at permissive temperatures (33 degrees C), but they undergo apoptosis at nonpermissive temperatures (37~39 degrees C) by the release of p53 through inactivation of T antigen, which is called T antigen dependency. This study was aimed at examining if T antigen-independent clones can develop from CIH. METHODS: CIH established with a temperature-sensitive T antigen (WA1) were cultured continuously at 39 degrees C. Three clones (W39B, W39C, and W39J) survived at this temperature and was subject to following analyses: the morphology, growth, apoptosis, the expression of T antigen and p53, telomerase, and the T antigen gene sequence. RESULTS: WA1 proliferated at 33 degrees C with the population doubling time of 30.8 +/- 1.7 hours, but they underwent cell death at 39 degrees C. However, T antigen-independent clones (W39B, W39C, and W39C) proliferated at 39 degrees C without undergoing apoptosis, suggesting they lost the temperature-sensitive characteristics. WA1 expressed the T antigen at 33 degrees C, but not at 39 degrees C, and this temperature-sensitive pattern was maintained in T antigen-independent clones. In p53 expression, however, T antigen-independent clones revealed a different pattern. p53 was detected even at 39 degrees C where it normally would not be detected. Telomerase was activated in all the analyzed cell lines. A temperature-sensitive point mutation at nucleotide position 3505 of the WA1 was retained in all T antigen-independent clones. CONCLUSION: CIH can lost temperature-sensitive characteristics and acquire an ability to proliferate at nonpermissive temperatures. These changes might be related to the change of p53 rather than the change of T antigen itself in these cell lines.
Antigens, Viral, Tumor* ; Apoptosis ; Cell Death ; Cell Line ; Clone Cells ; Hepatocytes* ; Point Mutation ; Telomerase

OBJECTIVE: The ubiquitous human polyomavirus, JC virus(JCV) is the etiologic agent of the fatal demyelinating central nervous system(CNS) disease, progressive multifocal leukoencephalopathy(PML). Recent studies have reported the detection of the JCV in samples derived from several type of human neural tumors and suggested the possible association of JCV with CNS tumors. Here we report for the first time, the presence of JCV in Korean glioblastoma multiforme(GM) patients. METHODS: Two Korean GM patients were assayed for JCV. To detect JCV, we performed immunohistochemical analysis using anti-JCV and anti-glial fibrillary acidic protein(GFAP) serum and polymerase chain reaction(PCR) using primers. RESULTS: JCV antigen was detected in cytoplasm abundantly in cells of this tumor case. Also, GFAP immunoreactivity was predominantly observed in cytoplasm of the cells that were morphologically bizarred appearing astrocytes in GM. In addition, both of the large T antigen gene and the VP1 gene were detected and this result correspond with previous result of immunohistochemistry. CONCLUSION: Although it is not certain that GM is associated with the JCV, we are attempted to elucidate the possible implication of JCV in the tumorigenesis of certain human malignant gliomas.
Antigens, Viral, Tumor ; Astrocytes ; Brain* ; Carcinogenesis ; Cytoplasm ; Glioblastoma* ; Glioma ; Humans ; Immunohistochemistry ; JC Virus*

OBJECTIVE: It is still unclear how the abnormal hTERT expression is involved in the process of ovarian carcinogenesis. A recent report demonstrated that the introduction of c-erbB-2 could efficiently induce tumorigenicity of cells with the transfection of SV40 large T antigen and hTERT. It is designed to find correlation between overexpression of hTERT and c-erbB-2 in ovarian carcinogenesis. METHODS: Using immunohistochemistry, we tested whether overexpression of hTERT and c-erbB-2 were associated in ovarian cancer. Immunohistochemical staining of hTERT and c-erbB-2 was done in 63 cases of ovarian cancer. Overexpression of hTERT and c-erbB-2 were correlated to clinicopathological variables. RESULTS: Overexpression of hTERT was found in 7 (11.1%) of cases, whereas overexpression of c-erbB2 was founded in 3 (4.8%) of cases. It was found that overexpression of hTERT and c-erbB-2 were significantly correlated (p=0.03). Neither overexpression of hTERT nor that of c-erbB-2 was associated with any of clinicopathological variables, such as stage, grade, and histology. CONCLUSION: Although the significant correlation between hTERT and c-erbB-2 was found, the low frequency of overexpression of hTERT and c-erbB-2 suggests that cooperation of hTERT and c-erbB-2 may be minor mechanism of ovarian carcinogenesis.
Antigens, Viral, Tumor ; Carcinogenesis ; Immunohistochemistry ; Ovarian Neoplasms ; Receptor, erbB-2 ; Transfection

OBJECTIVE: It is still unclear how the abnormal hTERT expression is involved in the process of ovarian carcinogenesis. A recent report demonstrated that the introduction of c-erbB-2 could efficiently induce tumorigenicity of cells with the transfection of SV40 large T antigen and hTERT. It is designed to find correlation between overexpression of hTERT and c-erbB-2 in ovarian carcinogenesis. METHODS: Using immunohistochemistry, we tested whether overexpression of hTERT and c-erbB-2 were associated in ovarian cancer. Immunohistochemical staining of hTERT and c-erbB-2 was done in 63 cases of ovarian cancer. Overexpression of hTERT and c-erbB-2 were correlated to clinicopathological variables. RESULTS: Overexpression of hTERT was found in 7 (11.1%) of cases, whereas overexpression of c-erbB2 was founded in 3 (4.8%) of cases. It was found that overexpression of hTERT and c-erbB-2 were significantly correlated (p=0.03). Neither overexpression of hTERT nor that of c-erbB-2 was associated with any of clinicopathological variables, such as stage, grade, and histology. CONCLUSION: Although the significant correlation between hTERT and c-erbB-2 was found, the low frequency of overexpression of hTERT and c-erbB-2 suggests that cooperation of hTERT and c-erbB-2 may be minor mechanism of ovarian carcinogenesis.
Antigens, Viral, Tumor ; Carcinogenesis ; Immunohistochemistry ; Ovarian Neoplasms ; Receptor, erbB-2 ; Transfection

BACKGROUND: Group A streptococci (GAS), the most common cause of bacterial pharyngitis, can be spread by interpersonal contact. While T typing is useful for screening, it does not completely identify organisms for epidemiological studies. The M protein is the most important virulence marker but has a drawback for epidemiological studies in that it is difficult to maintain the more than 80 necessary kinds of sera. The emm gene, which encodes the M protein, has variable sequences at the 5' N terminus, and emm genotyping using PCR and automatic sequencing has been reported lately. METHODS: Beta-hemolytic streptococci (BHS) were isolated from the throats of elementary school children in Jinju. T typing and emm genotyping was performed and compared with the T and M typing results of 1995. RESULTS: One hundred seventeen (20.1%) from 581 children yielded BHS, of which 83.8% were group A. T non-typeable strains were the most common (43.9%) and T12 was next (27.6%). The emm 12 was most frequent (33.7%), and emm 75 (10.2%), emm 18 (9.2%), emm 22 (8.2%), and emm 1 (7.1%) were relatively common. emm 2, 18, 50 and 75 were newly recognized. The isolation rate of BHS was 32.4% of which 57.1% was group A in 1995. T12 (44.7%) and T28 (13.2%) were the most common, and M12 (26.3%) and M28 (10.5%) were frequently identified in 1995. CONCLUSIONS: GAS was relatively common in school children. The distribution of the T antigen did not change significantly except for the T non-typeable since 1995. emm genotypes were diverse and emm 2, 18, 50 and 75 were newly recognized. Continuous microbiologic and epidemiological surveillance for GAS should be conducted in the community.
Antigens, Viral, Tumor ; Child* ; Epidemiologic Studies ; Genotype ; Gyeongsangnam-do ; Humans ; Mass Screening ; Pharyngitis ; Pharynx ; Polymerase Chain Reaction ; Virulence

BACKGROUND: T antigens and emm genotypes are useful markers for epidemiologic investigation of Streptococcus pyogenes infections. Epidemiologic studies of S. pyogenes were performed on a large scale in Jinju. This was the third study being carried out in the same area over the past 10 years. METHODS: A total of 328 S. pyogenes were isolated from throat cultures obtained from asymptomatic schoolchildren in the Jinju area in 2004. T typing was performed by a slide agglutination, and emm genotyping by PCR and DNA sequencing. We compared the results of this study with those of the previous ones performed in 1995 and 2002. RESULTS: T5/27/44 were the most prevalent, accounting for 29.6% of all isolates; T12 and T6 were 13.4% and 10.7%, respectively, and T nontypeable was 3.4%. The emm44/61 type was the most prevalent accounting for 29.3%, and emm6 and emm1 were 11.6% and 9.8%, respectively. CONCLUSIONS: Newly recognized T5/27/44 and emm44/61 were the most prevalent, accounting for about 30% of all isolates, while T12 and emm12 were significantly decreased in 2004 compared to the results of previous years. This study demonstrated divergent features of S. pyogenes epidemiology over the past 10 years in the Jinju area.
Agglutination ; Antigens, Viral, Tumor ; Epidemiologic Studies ; Epidemiology ; Genotype* ; Gyeongsangnam-do* ; Pharynx ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Streptococcus pyogenes* ; Streptococcus*

The T-antigen(Thomsen-Friedenreich antigen, T-Ag) has been found in malignant cells but in most normal cells, in which the T-Ag is cryptic but can be unmasked with neuraminidase. The significance of T-Ag expression in urinary bladder cancer by staining paraffin sections with a T-specific lectin(Peanut agglutinin, PNA) immunoperoxidase technic was investigated. Sixty-five cases of transitional cell carcinoma were divided into three grades as I, II and III by the degree of cellular differentiation and four groups as A : superficial tumors without recurrence, B ; superficial tumors with recurrence but without up-staging, C :superficial tumors with recurrence and up-staging and D ; initially invasive tumors accordingly. Over all T-Ag positive rate in transitional cell carcinomas was 37% and 5 normal and 5 inflammatory vesical mucosas were negative for T-Ag. In 95% of transitional cell carcinomas initially negative for T-Ag, cryptic T-Ag became positive after neuraminidase treatment. The control subjects initially all negative for T-Ag became positive for cryptic T-Ag after neuraminidase treatment. The T-Ag positive rates of group A, B, C and D were 25%, 30%. 50% and 58%, respectively and those of grade I, II and III were 28%, 37% and 47%, respectively. The positive rate of T-Ag was correlated with the grade but not with the recurrence or invasiveness. Also, T-Ag expression was not correlated with ABO(H) blood group. These conflicting data suggest that further extensive study will be necessary whether immunohistochemical detection of T-Ag in tissue sections could be of prognostic value in patients with transitional cell carcinoma.
Antigens, Viral, Tumor* ; Carcinoma, Transitional Cell* ; Humans ; Immunoenzyme Techniques ; Mucous Membrane ; Neuraminidase ; Paraffin ; Recurrence ; Urinary Bladder Neoplasms ; Urinary Bladder*