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Shugo Nawata

Publications and source records attributed to Shugo Nawata.

10 recordsLinked to original sources
PubMed2006

Different expression patterns of intact forms of squamous cell carcinoma antigens between normal and malignant cervical squamous epithelial tissues: nondenaturing polyacrylamide gel electrophoretic analysis.

Squamous cell carcinoma antigen (SCCA), a 45-kDa tumor-associated serpin, mainly consists of two highly homologous molecules, SCCA1 and SCCA2, which possess unique proteinase inhibitory properties. Importantly, our previous study demonstrated that an intact structure of SCCAs, and not a cleaved form yielded by interacting with target proteinase, is essential for their function as a serpin. The aim of this study is therefore, to develop a simple method of analyzing expression patterns of intact forms of SCCAs (functional SCCAs) in cervical squamous epithelial tissues and to investigate whether there are any differences in the expression of intact forms of SCCAs between normal and malignant cervical squamous epithelial tissues. We used nondenaturing polyacrylamide gel electrophoresis (PAGE) with immunoblotting. The newly generated antibody, Pab Y2, recognizes only intact form of SCCAs, while the conventional antibody, Mab 27, reacts with the cleaved form of SCCA1 as well as intact forms of SCCAs. Nondenaturing PAGE using Pab Y2 showed that an intact form of SCCAs in the heat-treated tissue extract at 60 degrees C for 2 h was separated into at least five bands, termed as bands A-E from cathode to anode. By comparison with two-dimensional electrophoresis patterns of SCCAs, it was found that the first three bands, i.e. bands A-C, are derived from the intact form of SCCA1, while the other two bands, i.e. band D and E are from the intact form of SCCA2. Specifically, band E, but not band D, of SCCA2 is apparently increased in squamous cell carcinomas compared with normal squamous epithelium. In conclusion, this novel analytical approach will be useful for investigating the different expression patterns of functional SCCAs between normal and malignant cervical squamous epithelial tissues.

Antigens, Neoplasm↗
PubMed2006

Suppression of SCC antigen promotes cancer cell invasion and migration through the decrease in E-cadherin expression.

Squamous cell carcinoma antigen (SCCA) is a useful tumor marker for diagnosis and management of squamous cell carcinoma. Recent studies have shown that SCCA can influence the behavior of cancer cells. It is well known that cell-cell adhesion is an important factor for the progression of cancer. The present study, therefore, was undertaken to investigate the effect of SCCA2 on the cell adhesion related molecule, E-cadherin, and cancer cell behavior. For this purpose, antisense SCCA2 cDNA was transfected into human uterine cancer cell lines, SKG IIIa and SiHa, which express SCCA2. Suppression of SCCA2 expression by antisense SCCA2 cDNA transfection decreased E-cadherin expression and promoted cell migration and invasion as well as the blockage of E-cadherin function by anti-E-cadherin antibody administration. In conclusion, SCCA2 regulates cell migration and invasion via E-cadherin expression, suggesting that SCCA2 may be involved in cancer behavior such as invasion or metastasis.

Antigens, Neoplasm↗
PubMed2005

Promoter analyses of SCC antigen genes.

SCC antigen (SCCA) has been used as a tumor marker for squamous cell carcinoma. Analyses of the SCCA1 and SCCA2 genes, which are almost identical, and their promoters have been reported. Recently it was found that both SCCAs were stimulated by interleukin (IL)-4 and IL-13. Here we analyzed the promoter activity of both SCCAs in the 5'-flanking region, exon 1, and intron 1 to evaluate a putative STAT6 binding site. The addition of intron 1 to the luciferase assay constructs including the 5'-flanking region significantly augmented the promoter activity of both SCCA1 and SCCA2. Furthermore, deletion analyses of intron 1 revealed that a 50-bp fragment of intron 1 that includes putative STAT6 binding site was responsible for the increased promoter activity. Although the sequences of SCCA1 and SCCA2 are very similar in the 5'-flanking region, the analysis of the -337 single nucleotide polymorphism of SCCA2 indicated that this polymorphism may underlie the difference in promoter activity between SCCA1 and SCCA2.

Amino Acid Sequence↗
PubMed2005

Tumor-associated serpin, squamous cell carcinoma antigen stimulates matrix metalloproteinase-9 production in cervical squamous cell carcinoma cell lines.

Squamous cell carcinoma antigen (SCCA) is clinically used as a tumor marker for patients with squamous cell carcinoma of various organs. SCCA1 and its highly homologous molecule, SCCA2, belong to the serine proteinase inhibitors (serpins) family, suggesting that these proteins may be involved in the malignant behavior of squamous cell carcinoma cells. The aim of this study is to functionally characterize these tumor-associated serpins regarding the potential to influence the production of matrix metalloproteinases (MMPs), which play a key role in tumor cell invasion and metastasis. Cervical squamous cell carcinoma cell lines, CaSki cells and SKG-IIIa cells were incubated with SCCA1 or SCCA2 and MMP production was analyzed by gelatin zymography. Both SCCA1 and SCCA2 significantly increased production of proMMP-9, but not proMMP-2. These stimulatory effects were still observed when cells were treated with SCCA mutants lacking the proteinase inhibitory activity of serpins. Furthermore, treatments with various forms of SCCAs, which are generated by interacting with their target proteinases, diminished the stimulatory effect of SCCAs, implying the importance of the conformational structure of SCCAs in the stimulatory effects of SCCAs on proMMP-9 production. In addition, in vitro invasion assay showed that SCCA1 and SCCA2 significantly promoted the activity of cell invasion. It is concluded that SCCAs can alter the invasive phenotype of cervical squamous cell carcinoma cells, probably by stimulating proMMP-9 production, and that intact conformational structure of SCCAs, but not proteinase inhibitory activity of serpins, is required for its stimulatory activity on proMMP-9 production.

Antigens, Neoplasm↗
PubMed2004

Regulation of squamous cell carcinoma antigen production by E-cadherin mediated cell-cell adhesion in squamous cell carcinoma cell line.

Squamous cell carcinoma antigen (SCCA) is a useful tumor marker for diagnosis and management of squamous cell carcinoma. It is well known that cell-cell adhesion is important for progression of cancer. However, it is not clarified whether cell-cell adhesion affects SCCA production in squamous cell carcinoma. The present study was, therefore, undertaken to investigate whether E-cadherin-mediated cell-cell adhesion affects SCCA production in squamous cell carcinoma of the uterine cervix. SKG-IIIa cells or CaSki cells, cervical squamous cell carcinoma cell lines, were treated with anti-E-cadherin antibodies (1 microg/ml) up to 72 h. The cells were dissociated, and SCCA content in the cytosol and SCCA mRNA levels were significantly decreased compared to the control group treated with mouse IgG. Secondly, the signaling pathway for SCCA production mediated by E-cadherin was examined. Phosphatidylinositol (PI) 3-kinase is a well-known mediator of E-cadherin-mediated biological events. The treatment with a PI 3-kinase inhibitor suppressed SCCA production in SKG-IIIa cells. It is concluded that E-cadherin mediated cell-cell adhesion maintains SCCA production through PI 3-kinase in squamous cell carcinoma.

Antibodies, Neoplasm↗
PubMed2003

Electrophoretic analysis of the cleaved form of serpin, squamous cell carcinoma antigen-1 in normal and malignant squamous epithelial tissues.

The aim of this study was to detect the cleaved form of serine proteinase inhibitor (serpin), squamous cell carcinoma (SCC) antigen-1 in normal and malignant squamous epithelial tissues, which implies the presence of its target proteinase. The cleaved SCC antigen-1 in normal squamous epithelium was identified as a single spot with pI 6.35 and M(r) 40,000 by two-dimensional electrophoresis (2-DE) combined with immunoblotting. Interestingly, the cleaved form showed different biochemical properties in heat stability or immunoreactivity with a monoclonal antibody for SCC antigen (Mab 426) compared to intact SCC antigen-1. Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of tissue extracts showed an abundant 40 kDa band of cleaved SCC antigen-1 in tumor tissue compared to normal tissue. Among the potential target proteinase of SCC antigen-1, immunoblotting analyses revealed that cathepsin L2 was remarkably overexpressed in tumor tissue, while cathepsin L was expressed in both normal and tumor tissues. These findings indicate that SCC antigen-1 interacts with specific endogenous proteinases such as cathepsins L and L2 in physiological and pathological states of squamous epithelium.

Antigens, Neoplasm↗
PubMed2002

Comparative genomic hybridization detects genetic alterations during early stages of cervical cancer progression.

Invasive cervical carcinoma is thought to arise from cervical intraepithelial neoplasm (CIN). Genetic changes that occur during progression of CIN to cervical carcinoma are poorly understood, although they appear to be directly involved in this process. We used comparative genomic hybridization (CGH) with precise microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) to detect genetic alterations in normal epithelial, CIN, and invasive carcinoma tissues colocalized in tumors from 18 patients with squamous cell carcinoma of the uterine cervix. Gains on chromosome 1 and on 3q and losses on 2q, 3p, 4, 6p, 11q, and 17p were frequent alterations found in CIN and invasive carcinoma lesions. Interestingly, several of these genetic changes were observed in preinvasive carcinoma lesions. The frequency and average number of genetic alterations corresponded directly to the extent to which the cervical carcinoma had progressed. Frequent alterations were found in more than 90% of CIN III lesions. Gains on 3q and losses on 11q were the most prevalent genetic alterations found in association with uterine cervix carcinogenesis. The common regions of alteration were 3q26.1-q28 and 11q23-qter. The majority of tumor samples showed variability in genetic alterations across lesion types within a single specimen.

Carcinoma, Squamous Cell↗
PubMed2002

Syndecan-1 expression in cancer of the uterine cervix: association with lymph node metastasis.

The development of carcinoma is associated with alterations in the expression of many cell adhesion molecules. Syndecan-1 is a cell surface proteoglycan that binds cells to the extracellular matrix and changes its expression following malignant transformation in some tumors. Our purpose was to examine the pattern of syndecan-1 expression in cancer of the uterine cervix and assess the clinicopathological significance of syndecan-1 expression. A total of 106 tissue specimens (6 normal, 19 cervical intraepithelial neoplasia (CIN) and 81 invasive cancer) were analyzed immunohistochemically. In addition, the corresponding expression of mRNA in tumor tissues was evaluated by reverse transcription-polymerase chain reaction (RT/PCR) in comparison with normal counterparts. Syndecan-1 was positive in normal squamous cells except the basal cell layer. The intensity of syndecan-1 staining was the strongest in normal epithelium, followed by CIN, and invasive squamous cell carcinoma. Syndecan-1 expression in cancer tissue tended to be higher in keratinizing type than non-keratinizing type and not found in adenocarcinoma. Syndecan-1 expression was markedly decreased at the mRNA level in invasive squamous cell carcinoma as compared with that of normal uterine cervix. Interestingy, there was an inverse correlation between the expression of syndecan-1 in the primary site and lymph node metastasis, although there was no significant correlation between syndecan-1 expression and the prognosis. The results of the present study suggest that syndecan-1 expression is associated with squamous tissues and plays a key role in the progression of the cancer of the uterine cervix especially in the metastatic process.

Adult↗
PubMedDate not supplied

Genetic alterations related to lymph node metastasis and peritoneal dissemination in epithelial ovarian cancers.

Genetic alterations are assumed to be necessary for the development and progression of ovarian cancer. However, the genetic alterations that occur during lymph node metastasis and peritoneal dissemination are poorly understood. In the present study, we used comparative genomic hybridization to detect genetic alterations in 30 tumors from patients with primary ovarian cancers and analyzed the associations of these genetic alterations with clinical stage and surgical pathological factors, such as histological grade, lymph node metastasis, and peritoneal dissemination. The total number of genetic alterations per tumor ranged from 0 to 39, with an average of 17.7 alterations per tumor. Among the genetic alterations in ovarian cancers, gains on chromosomes 8q and 3q and losses on chromosomes 17p, 18q, and 4q were observed frequently. Although the difference in total numbers of genetic alterations between early-stage tumors and advanced-stage tumors was not significant, the difference was significant when high-grade cancers were compared with low-grade cancers. Eight regions on seven chromosomes showed genetic alterations related to lymph node metastasis or peritoneal dissemination. Gain at 11q13-q14 and loss at 17q11.2-q21 were related not only to lymph node metastasis and peritoneal dissemination but also to clinical stage and histological grade.

Chromosomes, Human, Pair 11↗