Andruska Neal, Mao Chengjian, Cherian Mathew, Zhang Chen, Shapiro David J
Department of Biochemistry, University of Illinois, Urbana, IL, USA.
J Biomol Screen. 2012 Aug;17(7):921-32. doi: 10.1177/1087057112442960. Epub 2012 Apr 12.
Estrogens, acting through estrogen receptor α (ERα), stimulate breast cancer proliferation, making ERα an attractive drug target. Since 384-well format screens for inhibitors of proliferation can be challenging for some cells, inhibition of luciferase-based reporters is often used as a surrogate end point. To identify novel small-molecule inhibitors of 17β-estradiol (E(2))-ERα-stimulated cell proliferation, we established a cell-based screen for inhibitors of E(2)-ERα induction of an estrogen response element (ERE)(3)-luciferase reporter. Seventy-five "hits" were evaluated in tiered follow-up assays to identify where hits failed to progress and evaluate their effectiveness as inhibitors of E(2)-ERα-induced proliferation of breast cancer cells. Only 8 of 75 hits from the luciferase screen inhibited estrogen-induced proliferation of ERα-positive MCF-7 and T47D cells but not control ERα-negative MDA-MB-231 cells. Although 12% of compounds inhibited E(2)-ERα-stimulated proliferation in only one of the ERα-positive cell lines, 40% of compounds were toxic and inhibited growth of all the cell lines, and ~37% exhibited little or no ability to inhibit E(2)-ERα-stimulated cell proliferation. Representative compounds were evaluated in more detail, and a lead ERα inhibitor was identified.
雌激素通过雌激素受体α（ERα）发挥作用，刺激乳腺癌增殖，使ERα成为一个有吸引力的药物靶点。由于对某些细胞进行384孔板格式的增殖抑制剂筛选可能具有挑战性，基于荧光素酶的报告基因抑制通常被用作替代终点。为了鉴定17β-雌二醇（E₂）-ERα刺激的细胞增殖的新型小分子抑制剂，我们建立了一个基于细胞的筛选方法，用于筛选E₂-ERα诱导雌激素反应元件（ERE）-荧光素酶报告基因的抑制剂。在分层后续试验中对75个“命中”化合物进行了评估，以确定哪些命中化合物未能继续推进，并评估它们作为E₂-ERα诱导的乳腺癌细胞增殖抑制剂的有效性。在荧光素酶筛选的75个命中化合物中，只有8个抑制了雌激素诱导的ERα阳性MCF-7和T47D细胞的增殖，但没有抑制对照的ERα阴性MDA-MB-231细胞。虽然12%的化合物仅在其中一种ERα阳性细胞系中抑制了E₂-ERα刺激的增殖，但40%的化合物具有毒性，抑制了所有细胞系的生长，约37%的化合物几乎没有或完全没有抑制E₂-ERα刺激的细胞增殖的能力。对代表性化合物进行了更详细的评估，并鉴定出一种主要的ERα抑制剂。
