Synthesis of 11 steroid hormones in human adrenocortical carcinoma cells (H295R) was measured in a high-throughput steroidogenesis assay (HT-H295R) for 656 chemicals in concentration-response as part of the US Environmental Protection Agency's ToxCast program. This work extends previous analysis of the HT-H295R dataset and model by examining the utility of a novel prioritization metric based on the Mahalanobis distance that reduced these 11-dimensional data to 1-dimension via calculation of a mean Mahalanobis distance (mMd) at each chemical concentration screened for all hormone measures available. Herein, we evaluated the robustness of mMd values, and demonstrate that covariance and variance of the hormones measured appear independent of the chemicals screened and are inherent to the assay; the Type I error rate of the mMd method is less than 1%; and, absolute fold changes (up or down) of 1.5 to 2-fold have sufficient power for statistical significance. As a case study, we examined hormone responses for aromatase inhibitors in the HT-H295R assay and found high concordance with other ToxCast assays for known aromatase inhibitors. Finally, we used mMd and other ToxCast cytotoxicity data to demonstrate prioritization of the most selective and active chemicals as candidates for further in vitro or in silico screening.

中文翻译：

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使用高通量 H295R 数据的综合统计分析开发化学介导对类固醇生成影响的优先排序方法。

作为美国环境保护署 ToxCast 计划的一部分，在高通量类固醇生成分析 (HT-H295R) 中测量了 656 种化学物质的浓度响应，从而测量了人类肾上腺皮质癌细胞 (H295R) 中 11 种类固醇激素的合成。这项工作扩展了先前对 HT-H295R 数据集和模型的分析，通过检查基于马哈拉诺比斯距离的新优先级度量的效用，通过计算平均马哈拉诺比斯距离 (mMd) 将这些 11 维数据减少到一维针对所有可用的激素措施筛选化学浓度。在此，我们评估了 mMd 值的稳健性，并证明所测量的激素的协方差和方差似乎与筛选的化学物质无关，并且是测定所固有的；mMd方法的I类错误率小于1%；并且，1.5 到 2 倍的绝对倍数变化（向上或向下）具有足够的统计显着性。作为案例研究，我们在 HT-H295R 测定中检查了芳香酶抑制剂的激素反应，发现与已知芳香酶抑制剂的其他 ToxCast 测定高度一致。最后，我们使用 mMd 和其他 ToxCast 细胞毒性数据来证明优先选择最具选择性和活性的化学品作为进一步体外或计算机筛选的候选物。