Effect of prolactin on growth and the estrogen receptor level of human breast cancer cells (MCF-7).
Effect of prolactin on growth and the estrogen receptor level of human breast cancer cells (MCF-7).
复制标题
催乳素对人乳腺癌细胞（MCF-7）生长和雌激素受体水平的影响。
作者：
S. Shafie;S. Brooks
研究表明，催乳素可以修饰人乳腺癌细胞系MCF-7中细胞内特异性17 β-雌二醇结合。绵羊和人催乳素都使雌二醇受体（E2 R）水平增加一倍，但后者在浓度基础上的刺激性至少增加10倍。大部分E2 R复合物（约80%）被转运到细胞核，催乳素刺激反映在氚化17 β-雌二醇的核摄取升高。当E2 R刺激最大时，绵羊和人催乳素都不改变细胞的生长速率。胰岛素（10 μ g/ml）刺激氚化胸苷掺入和总DNA含量，但对E2 R浓度没有明显影响。在10（-4）M时，N6，O2 ′-二丁酰环腺苷3 ′：5 ′-单磷酸增加胰岛素对氚化胸苷掺入的刺激，并引起催乳素对表观DNA合成的刺激。茶碱（10（-3）M）阻断N6，O2 '-二丁酰环腺苷3'：5 '-单磷酸的这两种作用。催乳素作为MCF-7细胞的分化和生长的效应器的可能机制进行了讨论。
The intracellular specific 17beta-estradiol binding in the human breast cancer cell line, MCF-7, was shown to be modified by prolactin. Both ovine and human prolactin doubled the estradiol receptor (E2R) level, but the latter was at least 10 times more stimulatory on a concentration basis. Most of the E2R complex (approximately 80%) was transported to the nucleus, and the prolactin stimulation was reflected in an elevated nuclear uptake of the tritiated 17beta-estradiol. Neither ovine nor human prolactin altered the growth rate of the cells when E2R stimulation was maximal. Insulin (10 mug/ml) stimulated tritiated thymidine incorporation and total DNA content but had no apparent effect on E2R concentration. At 10(-4) M, N6,O2'-dibutyrylcyclicadenosine 3':5'-monophosphate increased insulin stimulation of tritiated thymidine incorporation and brought about a prolactin stimulation of apparent DNA synthesis. Theophylline (10(-3) M) blocked both of these effects of N6,O2'-dibutyrylcyclicadenosine 3':5'-monophosphate. The possible mechanism implicating prolactin as an effector of differentiation and growth of MCF-7 cells is discussed.