Sex hormone response of a newly established squamous cell line derived from clinical esophageal carcinoma.

Biopsy tissues from a 68-year-old Japanese man with metastases to axillary lymph nodes of a recurrent esophageal carcinoma were adapted to cell culture conditions and a continuously growing tumor cell line was developed. Immunohistochemical staining revealed that these cells contained keratinous material and the electron microscopic study revealed the presence of tonofilaments. Thus, this line, designated the KSE-1 line, was considered to have originated from metastatic squamous cell carcinoma of the esophagus. This line has a binding content of 4.2 fmol/mg protein for the estrogen receptor and 2.2 fmol/mg protein for the testosterone receptor. By measurement of cell number and thymidine incorporation, the growth rate of this line was found to be moderately responsive to these hormones, being inhibited by estrogen and enhanced by testosterone at concentration levels between 10(-13) and 10(-8) and 10(-13) and 10(-6) mg/ml, respectively.