GROWTH CHARACTERISTICS OF HEp-2 CELLS DIFFERING IN THEIR SUSCEPTIBILITY TO APOPTOSIS INDUCED BY STEROID HORMONES

Klyuchivska O., Yakymovych I., Stoika R.

We found that human larynx carcinoma cells of HEp-2E7 subline with an increased resistance to apoptosis-inducing action of 17b-estradiol, diethylstilbestrol, and tamoxifen, were characterized by more pronounced transformed phenotype (estimated by the anchorage-independent growth in semisolid agar culture medium) and shorter time of generation in comparison with the parental HEp-2 line. At the same time HEp-2E7 cells were more susceptible to suppressing action of anticancer drug cisplatin (500 ng/ml) than the parental HEp-2 cells, their susceptibility to the mistletoe lectin (50 ng/ml) being the same as in parental line. Thus, relative resistance of НЕр-2Е7 carcinoma cells to the apoptosis-inducing effect of sex steroids and their antagonist tamoxifen is probably unrelated to multidrug resistance, because these cells retain sensitivity to the other anticancer drugs.