[采用全细胞摄取法研究雌激素及内分泌治疗药物对MCF-7人乳腺癌细胞雌激素受体、孕激素受体及DNA合成的影响]

[Effects of estrogen and endocrine therapeutic agents on the estrogen receptor, progesterone receptor and DNA synthesis in MCF-7 human breast cancer cells using the whole cell uptake method].

作者信息

Kurebayashi J, Horiuchi R, Nakamura T, Iino Y, Ishida T, Takigawa H, Izuo M

机构信息

Second Department of Surgery, School of Medicine, Gunma University, Maebashi, Japan.

出版信息

Nihon Naibunpi Gakkai Zasshi. 1987 Nov 20;63(11):1351-63. doi: 10.1507/endocrine1927.63.11_1351.

DOI:10.1507/endocrine1927.63.11_1351

PMID:2965035

Abstract

In order to investigate the mechanisms of the endocrine therapeutic agents and the applicability of combined endocrine therapies for breast cancers, we studied the effects of estrogen and the endocrine therapeutic agents on estrogen receptor (ER), progesterone receptor (PgR), and DNA synthesis in MCF-7 human breast cancer cells, which is known to be sensitive to estrogen. ER and PgR of MCF-7 cells were determined by whole cell uptake method. In brief, intact MCF-7 cells cultured in the multi-well plates were incubated with various concentrations of tritiated estradiol (E2) or promegestone (R5020) at 37 degrees C for 1 hour. The characteristics of the hormone binding were analyzed by Scatchard plots. MCF-7 cells had single class of ER (Kd: 2.1 +/- 0.2 X 10(-10) M, MBC: 9.0 +/- 1.5 X 10(3) sites/cell) and PgR (Kd: 7.2 +/- 1.1 X 10(-10) M, MBC: 3.1 +/- 0.5 X 10(4) sites/cell). When cultured in the presence of 10(-8) M or 10(-6) M of E2, tamoxifen (TAM), R5020 or medroxyprogesterone acetate (MPA) for 48 hrs, the numbers of binding sites of ER and PgR altered, but the affinities of either of them did not change. E2(10(-8) or 10(-6) M) increased about twice the number of PgR. Although treatment of 10(-8) M TAM, a non-steroidal antiestrogen, slightly increased the number of PgR, 10(-6) M TAM significantly decreased the number of PgR. Both of R5020 (10(-8) or 10(-6) M) and MPA (10(-8) or 10(-6) M), synthetic progestins, decreased the number of ER dose-dependently. On the other hand, E2 (10(-8) and 10(-6) M) and R5020 (10(-8) M) enhanced DNA synthesis, but 10(-6) M TAM or MPA inhibited DNA synthesis. The effects of single, sequential and coincidental treatment of these agents were compared. The sequential treatment of 10(-8) M E2 for 36 hrs and followed 10(-6) M MPA for 36 hrs ("10(-8) M E2----10(-6) M MPA") and "10(-6) M TAM----10(-6) M MPA" inhibited DNA synthesis of MCF-7 cells more efficiently than 10(-6) M TAM alone or 10(-6) M MPA alone for 72 hrs. However, "10(-6) M MPA----10(-6) M TAM" inhibited DNA synthesis less than "10(-6) M TAM----10(-6) M MPA".(ABSTRACT TRUNCATED AT 400 WORDS)

摘要

为了研究内分泌治疗药物的作用机制以及联合内分泌疗法对乳腺癌的适用性，我们研究了雌激素和内分泌治疗药物对雌激素受体（ER）、孕激素受体（PgR）以及MCF-7人乳腺癌细胞中DNA合成的影响，已知MCF-7细胞对雌激素敏感。MCF-7细胞的ER和PgR通过全细胞摄取法测定。简而言之，在多孔板中培养的完整MCF-7细胞与各种浓度的氚标记雌二醇（E2）或醋酸甲羟孕酮（R5020）在37℃下孵育1小时。通过Scatchard图分析激素结合的特性。MCF-7细胞具有单一类别的ER（解离常数Kd：2.1±0.2×10⁻¹⁰M，最大结合容量MBC：9.0±1.5×10³个位点/细胞）和PgR（Kd：7.2±1.1×10⁻¹⁰M，MBC：3.1±0.5×10⁴个位点/细胞）。当在10⁻⁸M或10⁻⁶M的E2、他莫昔芬（TAM）、R5020或醋酸甲羟孕酮（MPA）存在下培养48小时时，ER和PgR的结合位点数量发生改变，但它们的亲和力均未改变。E2（10⁻⁸或10⁻⁶M）使PgR的数量增加约两倍。虽然10⁻⁸M的非甾体抗雌激素TAM略微增加了PgR的数量，但10⁻⁶M的TAM显著降低了PgR的数量。合成孕激素R5020（10⁻⁸或10⁻⁶M）和MPA（10⁻⁸或10⁻⁶M）均剂量依赖性地降低ER的数量。另一方面，E2（10⁻⁸和10⁻⁶M）和R5020（10⁻⁸M）增强DNA合成，但10⁻⁶M的TAM或MPA抑制DNA合成。比较了这些药物单一、序贯和联合治疗的效果。10⁻⁸M的E2处理36小时后接着10⁻⁶M的MPA处理36小时（“10⁻⁸M E2→10⁻⁶M MPA”）以及“10⁻⁶M TAM→10⁻⁶M MPA”比单独使用10⁻⁶M的TAM或10⁻⁶M的MPA处理72小时更有效地抑制了MCF-7细胞的DNA合成。然而，“10⁻⁶M MPA→10⁻⁶M TAM”对DNA合成的抑制作用小于“10⁻⁶M TAM→10⁻⁶M MPA”。（摘要截断于400字）