AROMATASE ACTIVITY IN RECEPTOR NEGATIVE BREAST AND ENDOMETRIAL CANCER
Among the factors for estrogen and progesterone receptors (ER and PR) negativity of tumors of reproductive tissue special attention is attracted by ability of the tumor produce estrogens (as intratumoral regulators of ER and PR) through reaction of aromatization. 101 samples of tumor tissue (64 cases of breast cancer and 37 cases of endometrial carcinomas) mostly from postmenopausal women were studied. When combined group of the tumors was divided on the basis of receptor-negativity or positivity (with cut-point correspondingly Ј and > 10 fM/mg protein) among samples with higher aromatase activity (> 7 fM/mg protein/h), a tendency to higher number of ER-negative tumors was found (p = 0.07). Such association was significant for breast (p = 0.04) but not for endometrial cancer (p > 0.5) samples. No evidence of PR contents dependence of tumor aromatase activity was revealed which may be connected with disturbance of estrogen signal transfer. Thus, inverse relation between steroid receptor levels and aromatase activity may be tissue- and receptor type-dependent.
No Comments » Add comments