This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Spancake, K. M. Articles by White, R. L. Search for Related Content PubMed PubMed Citation Articles by Spancake, K. M. Articles by White, R. L.

E7-transduced Human Breast Epithelial Cells Show Partial Differentiation in Three-dimensional Culture¹

Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 [K. M. S., C. B. A., N. M., R. L. W.], and Lawrence Berkeley National Laboratory, Berkeley, California 94720 [V. M. W., M. J. B.]

Disruption of the retinoblastoma (RB) tumor suppressor pathway is a common and important event in breast carcinogenesis. To examine the role of the retinoblastoma protein (pRB) in this process, we created human mammary epithelial cells (HMEC) deficient for pRB by infecting primary outgrowth from breast organoids with the human papillomavirus type 16 (HPV16) E7 gene. HPV16 E7 binds to and inactivates pRB and also causes a significant down-regulation of the protein. Culturing normal HMEC in a reconstituted basement membrane (rBM) provides a correct environment and signaling cues for the formation of differentiated, acini-like structures. When cultured in this rBM, HMEC+E7 were found to respond morphologically as normal HMEC and form acinar structures. In contrast to normal HMEC, many of the cells within the HMEC+E7 structures were not growth arrested, as determined by a 5-bromo-2'-deoxyuridine incorporation assay. pRB deficiency did not affect polarization of these structures, as indicated by the normal localization of the cell-cell adhesion marker E-cadherin and the basal deposition of a collagen IV membrane. However, in HMEC+E7 acini, we were unable to detect by immunofluorescence microscopy the milk protein lactoferrin or cytokeratin 19, both markers of differentiation expressed in the normal HMEC structures. These data suggest that loss of RB in vivo would compromise differentiation, predisposing these cells to future tumor-promoting actions.

This article has been cited by other articles:

				K. L. Schmeichel and M. J. Bissell Modeling tissue-specific signaling and organ function in three dimensions J. Cell Sci., June 15, 2003; 116(12): 2377 - 2388. [Abstract] [Full Text] [PDF]

				M. Mareel and A. Leroy Clinical, Cellular, and Molecular Aspects of Cancer Invasion Physiol Rev, April 1, 2003; 83(2): 337 - 376. [Abstract] [Full Text] [PDF]

				T. Gudjonsson, R. Villadsen, H. L. Nielsen, L. Ronnov-Jessen, M. J. Bissell, and O. W. Petersen Isolation, immortalization, and characterization of a human breast epithelial cell line with stem cell properties Genes & Dev., March 15, 2002; 16(6): 693 - 706. [Abstract] [Full Text] [PDF]

				V. L. Seewaldt, K. Mrozek, R. Sigle, E. C. Dietze, K. Heine, D. M. Hockenbery, K. B. Hobbs, and L. E. Caldwell Suppression of p53 function in normal human mammary epithelial cells increases sensitivity to extracellular matrix-induced apoptosis J. Cell Biol., October 29, 2001; 155(3): 471 - 486. [Abstract] [Full Text] [PDF]

				H. You, W. Yu, B. G. Sanders, and K. Kline RRR-{alpha}-Tocopheryl Succinate Induces MDA-MB-435 and MCF-7 Human Breast Cancer Cells to Undergo Differentiation Cell Growth Differ., September 1, 2001; 12(9): 471 - 480. [Abstract] [Full Text] [PDF]