Comparison of features of human breast cancer cell lines and their corresponding tumors

Although human tumor-derived cell lines play an important role in the inves tigation of cancer biology and genetics, there is no comprehensive study co mparing tumor cell line properties with those of the individual tumors from which they were derived. We compared the properties of a series of 18 huma n breast cancer cell lines that were cultured for a median period of 25 mon ths (range, 9-60 months) and their corresponding archival tumor tissues. We compared morphological characteristics, ploidy, and immunohistochemical ex pression of estrogen receptors, progesterone receptors, and HER2/neu and p5 3 proteins. For 17 of these cases, we also tested for allelic losses at 18 chromosomal regions frequently deleted in breast tumors using 51 polymorphi c microsatellite markers, and we determined the TP53 gene mutation status i n exons 5 to 10, There was an excellent correlation between the breast tumo r cell lines and their corresponding tumor tissues for morphological featur es (100%); presence of aneuploidy (87%); immunohistochemical expression of estrogen receptors (87%), progesterone receptors (73%), and HER2/neu (93%) and p53 proteins (100%); allelic loss at all of the chromosomal regions ana lyzed (82-100% concordance); and TP53 gene mutations (75%), The same parent al allele was lost in 279 (99%) of 281 of the comparisons of allele losses. The fractional allelic loss indices (a reflection of the total allelic los s) of the cell lines and their corresponding tumor tissues were identical o r similar in 15 (88%) of 17 paired comparisons, Although our previous studi es (A, Gazdar et at, Int. J, Cancer, in press) indicated that only a subset of primary breast carcinomas that have several features indicative of adva nced tumors with poor prognosis can be successfully cultured, the cell line s retain the properties of their parental tumors for lengthy culture period s and, thus, provide suitable model systems for biomedical studies.