TAILIEUCHUNG - Colorectal Cancer Methods and Protocols

The molecular analysis of human cancer is complicated by the difficulty in obtaining pure populations of tumor cells to study. One traditional method of obtaining a pure representation has been establishing cancer cell lines from primary tumors. However, this technique is time consuming and of low yield. Artifacts of cell culture include the selection of genetic alterations not present in primary tumors (1,2) and the alteration of gene expression as compared to primary tumors (3). When molecular techniques move from experimental to diagnostic settings, the need for robust, reproducible and “real time” testing will probably therefore require the direct analysis of tissue samples | M E T H O D S I N M O L E C U L A R M E D I C I N ETM Colorectal Cancer Methods and Protocols Edited by Steven M. Powell MD Humana Press 1 Microdissection of Histologic Sections Manual and Laser Capture Microdissection Techniques Christopher A. Moskaluk 1. Introduction The molecular analysis of human cancer is complicated by the difficulty in obtaining pure populations of tumor cells to study. One traditional method of obtaining a pure representation has been establishing cancer cell lines from primary tumors. However this technique is time consuming and of low yield. Artifacts of cell culture include the selection of genetic alterations not present in primary tumors 1 2 and the alteration of gene expression as compared to primary tumors 3 . When molecular techniques move from experimental to diagnostic settings the need for robust reproducible and real time testing will probably therefore require the direct analysis of tissue samples. Problems with the study of primary tissue samples include the heterogeneity of cell types and the range in the ratio of neoplastic cells relative to benign cells tumor cellularity . All tissues even malignant tumors are composed of a mixture of cell types. No tumors are free of supporting stromal cells fibroblasts endothelial cells and many tumors are invested with inflammatory cells and other residual benign tissue elements. Tumor cellularity and the degree of tumor necrosis not only varies between different neoplasms but can vary greatly between different areas in a single tumor mass. Molecular analyses of cancer in tissue samples may be hindered by insufficient number of viable target cells and a significant degree of contamination by nontarget cells. While it may be true that tests for specific genetic alterations may eventually make some histologic assessment superfluous 4 proposed gene expression profiling studies . microarray assays will require molecular analysis on pure representations of cancer cells 5 . Hence histologic

• Y học thường thức
• Histologic Sections
• Manual Microdissection
• DNA Isolation
• RNA Isolation
• Protein Isolation
• Manual Microdissection
• Frozen Histologic