ESTABLISHMENT OF AN ESTROGEN RECEPTOR-POSITIVE CELL-LINE (HMA-1) DERIVED FROM HUMAN BREAST-CARCINOMA

We have established a novel human breast carcinoma cell line, HMA-1, derived from ascites of a female breast cancer patient. HMA-1 was shown to be an epithelial cell line with intracytoplasmic duct-like vacuoles, microvilli, desmosomes and tonofibrils in accordance with human breast cancer. The cell line demonstrated a good cell growth ability in monolayer fashion with a doubling time of 46 hr. Based on a whole cell binding assay the cell line contained estrogen receptor (1.45 x 10(-4) sites/cell). Tamoxifen, an anti-estrogen agent induced a dose-dependent decrease in the cell growth rate, but estradiol stimulated the cell growth. HMA-1 could be transplanted subcutaneously into BALB/c nude mice, and was able to cause tumors approximately two months after heteroinoculation. These results indicate that HMA-1 cell line may serve as a new human breast carcinoma cell line which could be utilized in the breast cancer research.