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Identifying Cell Surface Markers of Primary Neural Stem and Progenitor Cells by Metabolic Labeling of Sialoglycan
Published on: September 7, 2019
Oligosaccharide Le(a)-Le(x): a cell surface marker for carcinomas derived from embryonic endoderm
P L Stranahan1, J LaRoe, R McCombs
1University of Colorado Cancer Center, Department of Biochemistry, Biophysics and Genetics, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
Oncology Reports
|April 4, 1998
Summary
Lewis antigens Le(a)-Le(x) are expressed in adenocarcinomas of the digestive system, originating from embryonic endoderm. This suggests investigating their role in both embryogenesis and carcinogenesis.
Area of Science:
- Oncology
- Developmental Biology
- Biochemistry
Background:
- Lewis antigens, including Le(a)-Le(x), are cell surface carbohydrates with roles in cell recognition.
- Previous studies identified Le(a)-Le(x) in non-small cell lung carcinomas and as a prognostic marker in squamous cell lung carcinomas.
Purpose of the Study:
- To evaluate Le(a)-Le(x) expression in adenocarcinomas of the biliary tree, pancreas, colon, and stomach.
- To determine if Le(a)-Le(x) expression is specific to tumors of embryonic endodermal origin.
Main Methods:
- Immunohistochemical analysis was used to detect Le(a)-Le(x) expression.
- Tumor specimens from the biliary tree, pancreas, colon, stomach, neural, connective, and muscle tissues were evaluated.
Main Results:
- All evaluated adenocarcinomas (biliary tree, pancreas, colon, stomach) showed positive Le(a)-Le(x) expression.
- No Le(a)-Le(x) expression was detected in neural, connective, or muscle tissues.
Conclusions:
- Le(a)-Le(x) expression is characteristic of epithelial tumors derived from embryonic endoderm.
- The biological significance of Le(a)-Le(x) in embryogenesis and carcinogenesis warrants further investigation.
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