KLE: a cell line with defective estrogen receptor derived from undifferentiated endometrial cancer.

KLE is a cell line derived from a poorly differentiated endometrial carcinoma that is aneuploid with chromosome numbers ranging from 51 to 66 and 6-8 marker chromosomes demonstrated by G banding. Tumors harvested from five of five nude mice bearing an inoculum for more than a month resemble the original specimen, and electron microscopy shows microvilli, many junctional processes, glycogenation, and a prominent nucleolonema. The cell cytosol contains a specific binder for estradiol, but there is no estrogen receptor in the nucleus and in a study reported elsewhere (Raam et al., Breast Cancer Res. Treat. 2, 277 (1982) ) translocation to the nucleus fails to occur. The enzyme phenotype of this cell is human, non-HeLa.