ESTABLISHMENT AND CHARACTERIZATION OF 2 NEW CELL-LINES DERIVED FROM HUMAN METASTATIC BREAST CARCINOMAS

Two human cancer cell lines (MA 2 and MA 3) were established from pleu ral effusions of infiltrating ductal carcinomas of the breast. The lin es were maintained in continuous monolayer culture with doubling times of 70 (MA 2) and 78 (MA 3) hr for more than two years and possessed e xtensively rearranged abnormal karyotypes with modal chromosome number of 83 (MA 2) and 81 (MA 3) and DNA index values of 1.65 and 1.77, res pectively. No amplifications or rearrangements were evident in the c-m yc, int-2, c-erb B2, c-Ha-ras, or hst 1 genes in MA 2 and MA 3 cell li nes. The clinical histories of the patients from whom the cell lines w ere derived are reported and compared with the results observed in the cell lines in vitro. The presence of CEA, CA 15-3, and MCA tumor mark ers observed in the primary tumor tissues was retained by the establis hed cell lines. While the primary tumor tissues were ER+/PgR borderlin e + (MA 2) and ER-/PgR+ (MA 3), the MA 2 line was ER+/PgR- and the MA 3 line remained ER-/PgR+. The MDR P-glycoprotein was not expressed eit her in primary tumor tissues or in the respective cell lines. High exp ression of cytokeratins 7, 18, and 19 was evident by immunohistochemic al analysis in each cell line, whereas cytokeratins 8 and 17 were poor ly or not at all expressed. The treatment history of the patients from whom the cell lines were derived involved CMF followed six months lat er by novantrone and cisplatin plus VP 16 (MA 2) and FEC followed four years later by CMF (MA 3). The chemosensitivity pattern assay of the cell lines indicated that the MA 2 line was sensitive to doxorubicin, cisplatin, and vinblastine, whereas the MA 3 line was sensitive to dox orubicin and cisplatin. The characteristics of these cell lines indica te them to be a good experimental model to investigate breast cancer b iology and anticancer drug response.