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Symposium: Pathology of Gastric Cancer
Pathology of Gastric Cancer . 307
121
123
DEGRADATION OF AP-l PRECEDES THE ONSET OF PULMONARY FIBROSIS M. Haase, D. Schuh, M. Muller, Institut fur Pathologie, TV Dresden
J. ROschoff, Kassel: Correlation between histology and molecular carcinogenesis in gastric cancer
Aims: Determination of the role of the transcription factor AP-l in the pathogenesis of radiation induced pulmonary fibrosis. Methods: Right lungs of female Fischer rats were irradiated with 20 Gy and developed a fibrosis after 2 Months. Morphological studies included standard immunohistology, in situ hybridization with the TSA system (Dako), and immunoelectron microscopy. DNA-binding assays (EMSA), western blotting, northern blotting was done using standard methods. 35S_labelled recombinant c-Jun was produced using the TnT Reticulocyte System (Promega). Results: EMSA revealed tbat only c-Jun and JunO bind significantly to the AP-l consensus binding site. Those two proteins as well as their mRNA are present in the metabolically most active cells of the lung, type II pneumocytes and alveolar macrophages, as well as bronchiolar epithelial cells of control and fibrotic lungs. C-Jun is associated with mitochondria or lysosomes, whereas JunO is not. DNA binding activity of AP-l showed a short peak after 12 hand then a continuous increase to a maximal 21-fold induction compared to control after 4 weeks. Thereafter, a down-regulation occurs leading to a complete loss of AP-l DNA binding activity after 5.5 weeks. This change is not due to changes in mRNA size or amount of expression. Western blot analysis showed a reduction of protein size of c-Jun and JunO from 39 kD to about 24 kD in parallel to the loss of DNA binding activity, suggesting a partial degradation of the proteins. "S-methionine-labelled recombinant c-Jun is degraded by protein extracts from fibrotic lungs but not by extracts from control lungs, mimicking the in vivo situation. Conclusions: C-Jun and JunO are degraded in radiated rat lungs prior to the development of pulmonary fibrosis, leading to a complete loss of DNA binding activity to the AP-l consensus sequence. This severe disturbation of a central regulatory pathway is likely to be the central switch towards active fibrosing alveolitis. Since this event occurs before the onset of fibrosis, it might be possible to identify and treat radiated patients prone to pulmonary fibrosis before the onset of active disease. The regulatory mechanism of degradation of transcription factors might be a common mechanism in the development of certain chronic diseases.
Symposium: Pathology of Gastric Cancer
122 WELL-DIFFERENTIATED ADENOCARCINOMA OR DYSPLASIA OF THE GASTRIC EPITHELIUM: RESULTS OF INTERNATIONAL COMPARATIVE STUDIES. R.J. Schlemper, A. Iwashita, M. Itabashi, Y. Kato, T. Shimoda, H. Watanabe, G. Oberhuber, M. Stolte. Fukuoka Univ., Ibaraki Pref. Centr. Hosp., Cancer Inst., National Cancer Center, Niigata Univ.; Univ. of Vienna; KIin. Bayreuth. Aim & Methods: To investigate intercountry differences in the diagnostic criteria for early gastric carcinoma, 31 pathologists from 12 countries reviewed 35 histologic slides of gastric lesions suspected to be neoplastic. Results: Suspected or definite carcinoma was diagnosed in 17-66% of the slides by 17 pathologists with a traditional Western viewpoint (North America, many European countries) and in 77-95% of the slides by 14 pathologists with a Japanese viewpoint (Japan, Germany, Austria, U.K.). Overall there was poor agreement between the traditional Western and Japanese diagnoses, namely in only 13 of the 35 slides (kappa value 0.16). The participants met and a consensus on the terminology was proposed: Vienna classification of gastrointestinal epithelial neoplasia (5 categories): 1. Negative for neoplasia/dysplasia 2. Indefinite for neoplasia/dysplasia 3. Non-invasive low-grade neoplasia: Low-grade adenoma/dysplasia 4. Non-invasive high-grade neoplasia: 4.1. High-grade adenoma/dysplasia 4.2. Non-invasive carcinoma (CIS) 4.3. Suspicious for invasive carcinoma 5. Invasive neoplasia: 5.1. Intramucosal carcinoma 5.2. Submucosal carcinoma or beyond When the original assessments of the slides were regrouped into the five categories of the Vienna classification, there was much better agreement among the pathologists, namely in 25 of the 35 slides (kappa value 0.55). Conclusion: To achieve international comparability of gastrointestinal histologic diagnoses we recommend that high-grade dysplasia, non-invasive carcinoma and suspected invasive carcinoma be grouped together into one category of non-invasive high-grade neoplasia.
Abstract not submitted
124 EXPRESSION OF P53 AND P21 (WAFlI CIPl) ANTIGEN IN GASTRIC CARCINOMA: AN IMMUNOHISTOCHEMICAL AND MOLECULAR BIOLOGICAL INVESTGATION S.E. Baldus, T.K. Zirbes, P. Schneider", S. Fromm, J. Glossmann, J. Lorenzen, W. Meyer, S. Schuler, S.P. Monig", J. Thiele, AH. Holscher", H.P. Dienes
Institut fiir Pathologie und "Klinik und Poliklinik fiir Viszeral- und Gefiflchirurgie, Universitiitzu Koln, D-50924 Kiiln Aims: As suggested by numerous in vitro as well as clinico-pathological studies, p53 antigen and related cyclin kinases like p21 play an important role in cancer biology. However, there are only limited data available regarding p21 expression and its relation to p53 in gastric carcinoma. Methods: Formalin-fixed and paraffin-embedded tissues from 196 patients with gastric cancer were studied by immunohistochemistry applying monoclonal antibodies against p53 and p21 antigen and the ImmunoMax technique. The staining results were correlated to pTNM and other histopathological classifications as well as survival data. 50 tissue specimens were also investigated by PCR and SSCP analysis in order to detect p53 mutations. Results: About 44 % of the carcinomas revealed an expression ofp53 in >50 % of tumor nuclei, whereas less than 20 % showed a marked reactivity of p21 protein (in> 20 % of tumor nuclei). The latter ~orrelated with better tumor differentiation (grade I and II), a tubular/papillary pattern and displayed a favorable outcome. Correlations of both antigens with pTNM stages were not observed. P53 expression was correlated with Lauren subtypes. P53 and p21 protein reactivities were also strongly correlated, but PCR and SSCP studies revealed that p53 protein overexpression was not accompanied by p53 mutations in many cases. Conclusions: P21 expression in gastric cancer shows correlations to grading, histopathological patterns and p53 expression. In contrast to p53, it may be an indicator of a more favorable prognosis. On the other hand, p53 protein was not associated with histopathological features and may often be over-expressed independently from gene mutations.
121
123
DEGRADATION OF AP-l PRECEDES THE ONSET OF PULMONARY FIBROSIS M. Haase, D. Schuh, M. Muller, Institut fur Pathologie, TV Dresden
J. ROschoff, Kassel: Correlation between histology and molecular carcinogenesis in gastric cancer
Aims: Determination of the role of the transcription factor AP-l in the pathogenesis of radiation induced pulmonary fibrosis. Methods: Right lungs of female Fischer rats were irradiated with 20 Gy and developed a fibrosis after 2 Months. Morphological studies included standard immunohistology, in situ hybridization with the TSA system (Dako), and immunoelectron microscopy. DNA-binding assays (EMSA), western blotting, northern blotting was done using standard methods. 35S_labelled recombinant c-Jun was produced using the TnT Reticulocyte System (Promega). Results: EMSA revealed tbat only c-Jun and JunO bind significantly to the AP-l consensus binding site. Those two proteins as well as their mRNA are present in the metabolically most active cells of the lung, type II pneumocytes and alveolar macrophages, as well as bronchiolar epithelial cells of control and fibrotic lungs. C-Jun is associated with mitochondria or lysosomes, whereas JunO is not. DNA binding activity of AP-l showed a short peak after 12 hand then a continuous increase to a maximal 21-fold induction compared to control after 4 weeks. Thereafter, a down-regulation occurs leading to a complete loss of AP-l DNA binding activity after 5.5 weeks. This change is not due to changes in mRNA size or amount of expression. Western blot analysis showed a reduction of protein size of c-Jun and JunO from 39 kD to about 24 kD in parallel to the loss of DNA binding activity, suggesting a partial degradation of the proteins. "S-methionine-labelled recombinant c-Jun is degraded by protein extracts from fibrotic lungs but not by extracts from control lungs, mimicking the in vivo situation. Conclusions: C-Jun and JunO are degraded in radiated rat lungs prior to the development of pulmonary fibrosis, leading to a complete loss of DNA binding activity to the AP-l consensus sequence. This severe disturbation of a central regulatory pathway is likely to be the central switch towards active fibrosing alveolitis. Since this event occurs before the onset of fibrosis, it might be possible to identify and treat radiated patients prone to pulmonary fibrosis before the onset of active disease. The regulatory mechanism of degradation of transcription factors might be a common mechanism in the development of certain chronic diseases.
Symposium: Pathology of Gastric Cancer
122 WELL-DIFFERENTIATED ADENOCARCINOMA OR DYSPLASIA OF THE GASTRIC EPITHELIUM: RESULTS OF INTERNATIONAL COMPARATIVE STUDIES. R.J. Schlemper, A. Iwashita, M. Itabashi, Y. Kato, T. Shimoda, H. Watanabe, G. Oberhuber, M. Stolte. Fukuoka Univ., Ibaraki Pref. Centr. Hosp., Cancer Inst., National Cancer Center, Niigata Univ.; Univ. of Vienna; KIin. Bayreuth. Aim & Methods: To investigate intercountry differences in the diagnostic criteria for early gastric carcinoma, 31 pathologists from 12 countries reviewed 35 histologic slides of gastric lesions suspected to be neoplastic. Results: Suspected or definite carcinoma was diagnosed in 17-66% of the slides by 17 pathologists with a traditional Western viewpoint (North America, many European countries) and in 77-95% of the slides by 14 pathologists with a Japanese viewpoint (Japan, Germany, Austria, U.K.). Overall there was poor agreement between the traditional Western and Japanese diagnoses, namely in only 13 of the 35 slides (kappa value 0.16). The participants met and a consensus on the terminology was proposed: Vienna classification of gastrointestinal epithelial neoplasia (5 categories): 1. Negative for neoplasia/dysplasia 2. Indefinite for neoplasia/dysplasia 3. Non-invasive low-grade neoplasia: Low-grade adenoma/dysplasia 4. Non-invasive high-grade neoplasia: 4.1. High-grade adenoma/dysplasia 4.2. Non-invasive carcinoma (CIS) 4.3. Suspicious for invasive carcinoma 5. Invasive neoplasia: 5.1. Intramucosal carcinoma 5.2. Submucosal carcinoma or beyond When the original assessments of the slides were regrouped into the five categories of the Vienna classification, there was much better agreement among the pathologists, namely in 25 of the 35 slides (kappa value 0.55). Conclusion: To achieve international comparability of gastrointestinal histologic diagnoses we recommend that high-grade dysplasia, non-invasive carcinoma and suspected invasive carcinoma be grouped together into one category of non-invasive high-grade neoplasia.
Abstract not submitted
124 EXPRESSION OF P53 AND P21 (WAFlI CIPl) ANTIGEN IN GASTRIC CARCINOMA: AN IMMUNOHISTOCHEMICAL AND MOLECULAR BIOLOGICAL INVESTGATION S.E. Baldus, T.K. Zirbes, P. Schneider", S. Fromm, J. Glossmann, J. Lorenzen, W. Meyer, S. Schuler, S.P. Monig", J. Thiele, AH. Holscher", H.P. Dienes
Institut fiir Pathologie und "Klinik und Poliklinik fiir Viszeral- und Gefiflchirurgie, Universitiitzu Koln, D-50924 Kiiln Aims: As suggested by numerous in vitro as well as clinico-pathological studies, p53 antigen and related cyclin kinases like p21 play an important role in cancer biology. However, there are only limited data available regarding p21 expression and its relation to p53 in gastric carcinoma. Methods: Formalin-fixed and paraffin-embedded tissues from 196 patients with gastric cancer were studied by immunohistochemistry applying monoclonal antibodies against p53 and p21 antigen and the ImmunoMax technique. The staining results were correlated to pTNM and other histopathological classifications as well as survival data. 50 tissue specimens were also investigated by PCR and SSCP analysis in order to detect p53 mutations. Results: About 44 % of the carcinomas revealed an expression ofp53 in >50 % of tumor nuclei, whereas less than 20 % showed a marked reactivity of p21 protein (in> 20 % of tumor nuclei). The latter ~orrelated with better tumor differentiation (grade I and II), a tubular/papillary pattern and displayed a favorable outcome. Correlations of both antigens with pTNM stages were not observed. P53 expression was correlated with Lauren subtypes. P53 and p21 protein reactivities were also strongly correlated, but PCR and SSCP studies revealed that p53 protein overexpression was not accompanied by p53 mutations in many cases. Conclusions: P21 expression in gastric cancer shows correlations to grading, histopathological patterns and p53 expression. In contrast to p53, it may be an indicator of a more favorable prognosis. On the other hand, p53 protein was not associated with histopathological features and may often be over-expressed independently from gene mutations.