Steroid hormone receptors and tumorigenicity of sublines from breast tumor metastatic MDA-MB 231 cell line.

Ten cell sublines the MDA-MB 231 human breast cell line were analyzed for their phenotypic diversity: morphology, karyotype, growth rate, clonogenicity in semisolid medium, tumorigenicity in nude mice, number and affinity of nuclear receptors for oestradiol, progesterone and glucocorticoids. Karyotypic analysis showed different aneuploidies from 50 to 120 chromosomes and variable chromosomal rearrangements in the analyzed subclones. All except two of the ten subclones were tumorigenic when injected subcutaneously or intraperitoneally into nude mice. Although the parental cell line has no receptor, all except two of the tested subclones contained various amounts of high affinity oestradiol and progesterone receptors ranging from 3,000 to 33,000 per cell. Seven subclones contained either high affinity oestradiol or progesterone receptors in nuclei. The diversity found in different subclones derived from one breast carcinoma cell line might represent variabilities acquired and selected continuously in culture.