摘要:

Metastasis, the major cause of cancer deaths, is represented by a complex, multistep cascade of events characterized by the interaction between neoplastic cells and host tissue elements (cells and extracellular matrix components). These interactions are mediated by specific receptors; among them are members of a growing family of heterodimeric cell surface glycoproteins, called integrins. The role of integrins along tumor progression key steps, as well as their value as diagnostic and prognostic markers are discussed herein. Emphasis on the nature of integrin-ligand interaction is given; in particular, concerning the role of carbohydrate moieties on the generation of diversity in integrin specificity and varying affinity states.

ISSN:1010-4283    

DOI:10.1159/000217732

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

In this report we describe the expression of the adenocarcinoma associated antigen recognized by the monoclonal antibody 44–3A6, in various tissues during normal human fetal development. Conventional, formalin-fixed and paraffin-embedded sections of normal organs were examined from fetuses ranging from 9 to 42 weeks of gestation. Immunohistochemical localization of antigen-antibody complexes was accomplished using the avidin-biotin complex (ABC) method using horseradish peroxidase. The monoclonal antibody (MAb) 44–3A6 detects a cell surface 40 kD protein which is frequently expressed by adenocarcinomas and by select normal glandular tissues. Detectable expression of this protein was seen at different time periods during fetal development depending on the tissue. This expression was confined to a relatively small range of cell types and tissues; immuno-staining was noted in select epithelial cells of the aerodigestive tract, exocrine pancreas, neural tissues, renal tubules, and transitional urothelium, as well as in other tissues. This immunostaining generally, but not invariably, corresponded with patterns previously reported in benign and/or malignant neoplasms of adult tissues. In most instances, once expression occurred within a tissue, it continued through gestation. These data show that this tumor associated gene product is differentially expressed in a broad range of normal developing human fetal tiss

ISSN:1010-4283    

DOI:10.1159/000217733

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Immunohistochemical deposition and distribution of fetal antigen 2 (FA2) was examined in normal brain tissue and in primary and metastatic tumors of the brain. In normal brain tissue FA2 was exclusively found linearly around the vessels, along pia and in arachnoidea. A similar localization was seen in primary brain tumors except in gliosarcoma where FA2 was distributed diffusely in the sarcoma region and was absent in the glioma region. In metastatic carcinoma with tumor stroma a diffuse staining reaction was seen in the stroma and with a basement membrane (BM) like staining at the tumor cell/stroma interface. Intracytoplasmic FA2 staining of the tumor cells was seen in areas without tumor stroma. In metastatic melanoma a BM like FA2 staining was seen around and between individual tumor cells. The staining patterns seen in the metastatic tumors were in accordance with that of the corresponding primary tumors.

ISSN:1010-4283    

DOI:10.1159/000217734

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Three cell lines established from human gliomas were found to differ in the capacity to phosphorylate the glycolytic enzyme pyruvate kinase in vitro. Phosphorylation in the glioblastoma cell line U-138 was more pronounced than in the glioma cell line Hs 683 and in the glioblastoma cell line A-172. All 3 cell lines showed similar pyruvate kinase isozyme patterns and expressed about 90% K-type and 10% M-type subunits. So, differences in pyruvate kinase phosphorylation could not be explained by differences in the availability of the appropriate substrate, being pyruvate kinase type K. As in gliomas, phosphorylation could specifically and almost completely be inhibited by fructose-1,6-bisphosphate. In order to investigate a potential physiological significance of the phosphorylation of pyruvate kinase, we have characterized these cell lines for several glycolytic parameters. In U-138 cells, the production of lactate appeared to be 2 times higher as compared with A-172 and Hs 683 cells under normal growth conditions and even 4 times higher under low glucose culture regime. The efflux of lactate correlated with the pyruvate kinase phosphorylation pattern in the cell lines. In none of the cell lines could the lactate production be stimulated by glutamine as additional energy source under low glucose culture conditions. The higher glycolytic flux in U-138 cells was not accompanied by higher glycolytic enzyme activities. The isozyme patterns of hexokinase, pyruvate kinase, aldolase, enolase and lactate dehydrogenase in the cell lines were nearly identical and resembled the patterns previously described for solid gliomas. However, the isozyme composition of phosphofructokinase in the cell lines differed from the situation in gliomas. While in gliomas the expression of L-type phosphofructokinase is favored, in the glioma cell lines, we found an increase in the expression of C-type subunits.

ISSN:1010-4283    

DOI:10.1159/000217735

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

α-Fetoprotein (AFP) levels measured by RIA show a strong sensitivity for the biological diagnosis of malignant hepatoma (MH). However, this parameter lacks specificity. Previous observations of an alteration in vitamin B12etabolism in the presence of hepatoma led us to study vitamin-B12-binding proteins. Vitamin B12, also called cobalamin, is transported in the blood by two proteins or transcobalamins: one is haptocorrin (HC), which is linked to most of the cobalamin, and the other is transcobalamin II, which is involved in tissue exchanges. In this work, the levels of AFP and transcobalamins were determined by RIA and radioisotope dilution assay, respectively. They were measured in patients with MH (group A) and in patients with other liver diseases (group B). Compared with group B, group A showed a significant increase in total serum HC (p < 0.005). In conclusion, it was observed that MH is accompanied by increased levels of HC. The origin of these changes could be due to either an increase in HC synthesis or a catabolic defect

ISSN:1010-4283    

DOI:10.1159/000217736

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Pretreatment levels of phosphohexose isomerase (PHI) were above the cutoff limit of 107 IU/1 in 41 % of patients with benign intestinal diseases and in 46% of patients with colorectal cancer. Sensitivity of PHI was related to the presence of distant metastasis and the location of the primary tumor/Patients with rectal tumors presented a lower sensitivity than patients with colonic tumors. Pretreatment levels of PHI had prognostic value and patients with elevated levels of this enzyme showed a shorter disease-free interval in comparison with those patients with normal PHI activities. However, the prognostic significance of PHI was not independent of Dukes’ classification. The present study indicates that PHI is not useful in the follow-up of patients with colorectal cancer after curative surgery because of its low sensitivity in the diagnosis of recurrences (47%) and its low specificity in patients without evidence of disease (76%

ISSN:1010-4283    

DOI:10.1159/000217737

出版商:S. Karger AG    

年代:1991

数据来源: Karger

ISSN:1010-4283    

DOI:10.1159/000217738

出版商:S. Karger AG    

年代:1991

数据来源: Karger

ISSN:1010-4283    

DOI:10.1159/000217739

出版商:S. Karger AG    

年代:1991

数据来源: Karger

ISSN:1010-4283    

DOI:10.1159/000217740

出版商:S. Karger AG    

年代:1991

数据来源: Karger

ISSN:1010-4283    

DOI:10.1159/000217731

出版商:S. Karger AG    

年代:1991

数据来源: Karger