Characterization of epithelial phenotypes in mortal and immortal human breast cells.
We have previously described the mortal human breast epithelial culture MCF-10M, that was derived from fibrocystic breast tissue, was cultivated in medium with low calcium content for over 2 years, and spontaneously gave rise to the immortal MCF-10 cell line. The emergence of immortalized cells, characterized by growth in conventional calcium levels, from mortal cells has proven to be a reproducible event. Here we report the establishment of a second immortal line from MCF-10M, designated MCF-10-2, and establishment of the MCF-12 immortal line after long-term cultivation of MCF-12M mortal cells from reduction mammoplasty tissue. DNA fingerprinting demonstrated the independent, human origin and lineage of the MCF-10-2 and MCF-12 cell lines. Both lines require cortisol and EGF for maximal growth. The expression in these cultures of in vivo breast epithelial phenotypes was analyzed using 2-dimensional gel Western blots and immunoperoxidase staining with antibodies to cytokeratins and polymorphic epithelial mucin. MCF-10M and MCF-12M retain the cytokeratin profile of the luminal cell (7, 8, 18, 19), and also express cytokeratin 14, found predominantly in basal cells. The immortal lines express a similar profile, except that cytokeratin 19, a component of the fully differentiated luminal cell, is not expressed in the more uniform population seen in MCF-10 and MCF-12, but is retained in the morphologically mixed, less-selected population of MCF-10-2. Epitopes on the polymorphic epithelial mucin, recognized by antibodies HMFG 1, HMFG 2 and SM-3, were detected in the mortal cultures and in the immortal lines, indicating the occurrence of both normal and abnormal mucin processing. MCF-10, MCF-10-2 and MCF-12 cells do not form tumors in nude mice, but appear to organize as duct-like structures before regressing in the 5th week post injection.
Michigan Cancer Foundation, Detroit 48201.
T M
TM
Paine
H D
HD
Soule
R J
RJ
Pauley
P J
PJ
Dawson
D000818:Animals; D000911:Antibodies, Monoclonal; D015153:Blotting, Western; D001940:Breast / Q000166:cytology* / Q000276:immunology; D002455:Cell Division; D002460:Cell Line; D002470:Cell Survival; D002999:Clone Cells; D016172:DNA Fingerprinting; D015180:Electrophoresis, Gel, Two-Dimensional; D004847:Epithelial Cells; D004848:Epithelium / Q000276:immunology; D006801:Humans; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D007633:Keratins / Q000737:chemistry; D051379:Mice; D008819:Mice, Nude; D012150:Polymorphism, Restriction Fragment Length; D013997:Time Factors
D000911:Antibodies, Monoclonal; D007633:Keratins