Gene Expression Profiles of Epithelial Cells Microscopically Isolated from a Breast-Invasive Ductal Carcinoma and a Nodal Metastasis

• Published in: Proceedings of the National Academy of Sciences - PNAS 2004-12, Vol.101 (52), p.18147-18152
• Main Authors: Zucchi, I, Mento, E, Kuznetsov, V A, Scotti, M, Valsecchi, V, Simionati, B, Vicinanza, E, Valle, G, Pilotti, S, Reinbold, R, Vezzoni, P, Albertini, A, Dulbecco, R
• Format: Article
• Language: English
• Subjects: Biological Sciences; Breast - metabolism; Breast cancer; Breast ductal carcinoma; Breast Neoplasms - genetics; Breast Neoplasms - pathology; Breasts; Carcinoma - genetics; Carcinoma - pathology; Cell growth; DNA, Complementary - metabolism; Down-Regulation; Epithelial cells; Epithelial Cells - metabolism; Epithelium - metabolism; Gene expression; Gene Expression Regulation, Neoplastic; Gene Library; Humans; In Situ Hybridization; Libraries; Lymphatic Metastasis; Stromal cells; T lymphocytes; Tumors; Up-Regulation
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0408260101

Expression profiles of breast carcinomas are difficult to interpret when they are obtained from tissue in toto, which may contain a large proportion of non-cancer cells. To avoid this problem, we microscopically isolated cells from a primary invasive ductal carcinoma of the breast and from an axillary node harboring a metastatic breast carcinoma, to obtain pure populations of carcinoma cells (≈500) and used them for serial analysis of gene expression. The expression profiles generated from both populations of cells were compared with the profile of a disease-free mammary epithelium. We showed that the expression profiles obtained are exclusive of carcinoma cells with no contribution of non-epithelial cells. From a total of 16,939 unique tags analyzed, we detected 559 statistically significant changes in gene expression; some of these genes have not been previously associated with breast cancer. We observed that many of the down-regulated genes are the same in both cancers, whereas the up-regulated genes are completely different, suggesting that the down-regulation of a set of genes may be the basic mechanism of cancer formation, while the up-regulation may characterize and possibly control the state of evolution of individual cancers. The results obtained may help in characterizing the neoplastic process of breast cancer.