Effect of ovariectomy on hormone receptors and growth of N-nitrosomethylurea-induced mammary tumors in the rat.
Effect of ovariectomy on hormone receptors and growth of N-nitrosomethylurea-induced mammary tumors in the rat.
复制标题
卵巢切除术对激素受体和 N-亚硝基甲基脲诱导的大鼠乳腺肿瘤生长的影响。
作者：
B. Arafah;P. Gullino;A. Manni;O. Pearson
在完整雌性Sprague-Dawley大鼠和卵巢切除术后9天的大鼠中，测定了N-亚硝基甲脲诱导的乳腺肿瘤中的雌激素受体（ER）、孕激素受体（PGR）、雄激素受体（ANR）和催乳素受体（PRLR）。卵巢切除术后，15个肿瘤中有12个消退至原始大小的47.7 +/- 5.5%（卵巢依赖性肿瘤），而其余3个生长停滞，达到其原始大小的88.8 +/- 7.3%。完整大鼠肿瘤细胞液ER水平为50.3 +/- 6.6 fmol/mg蛋白质，卵巢切除组明显较低（25.6 +/- 8.3 fmol/mg，p < 0.025）。完整大鼠的13个肿瘤中有10个肿瘤中存在大量的PGR（平均值为144.5 ± 46.8），但卵巢切除术后6个肿瘤中有5个肿瘤中检测不到PGR（p < 0.01）。ANR在13个完整的大鼠肿瘤中仅在4个中检测到低水平，但在卵巢切除术后的6个卵巢依赖性肿瘤中没有检测到。PRLR在完整和卵巢切除大鼠的肿瘤中没有显著差异（分别为20.6 +/- 2.4和15.6 +/- 1.8 fmol/mg）。在卵巢切除术后生长停滞的三个肿瘤中，ER、PGR、ANR和PRLR的水平与卵巢依赖性肿瘤的水平没有显著差异。我们的结论是大多数N-亚硝基甲脲诱导的大鼠乳腺肿瘤是激素依赖性的。ER、PGR和PRLR在这些肿瘤中的大多数中大量存在，而ANR仅存在于13个肿瘤中的4个中。卵巢切除后雌激素受体和孕激素受体水平明显降低，而催乳素受体无明显变化。
Estrogen receptor(s) (ER), progesterone receptor(s) (PGR), androgen receptor(s) (ANR), and prolactin receptor(s) (PRLR) were measured in N-nitrosomethylurea-induced mammary tumors in intact female Sprague-Dawley rats and in rats 9 days after ovariectomy. Following ovariectomy, 12 of 15 tumors regressed to 47.7 +/- 5.5% of the original size (hormone-dependent tumors), while the remaining three had arrest of growth reaching 88.8 +/- 7.3% of their original sizes. Cytosol ER level was 50.3 +/- 6.6 fmol/mg protein in tumors of intact rats and was significantly lower (25.6 +/- 8.3 fmol/mg, p < 0.025) in the ovariectomized group. PGR was abundantly present in ten of 13 tumors of intact rats (mean, 144.5 +/- 46.8) but was undetectable in five of six hormone-dependent tumors after ovariectomy (p < 0.01). ANR ws detectable at low levels in only four of 13 tumors of intact rats but in none of six hormone-dependent tumors after ovariectomy. PRLR was not significantly different in tumors of intact and ovariectomized rats (20.6 +/- 2.4 and 15.6 +/- 1.8 fmol/mg, respectively). In three tumors that had arrest of growth after ovariectomy, the levels of ER, PGR, ANR, and PRLR were not significantly different from those of the hormone-dependent tumors. We conclude that the majority of N-nitrosomethylurea-induced rat mammary tumors are hormone dependent. ER, PGR, and PRLR were abundantly present in the majority of these tumors, while ANR was present in only four of 13 tumors. The levels of ER and PGR were significantly lower following ovariectomy, while PRLR was not significantly changed.