There is strong evidence that inhibition of one or more Aldehyde Dehydrogenase 1A (ALDH1A) isoforms may be beneficial in chemotherapy-resistant ovarian cancer and other tumor types. While many previous efforts have focused on development of ALDH1A1 selective inhibitors, the most deadly ovarian cancer subtype, high-grade serous (HGSOC), exhibits elevated expression of ALDH1A3. Herein, we report continued development of pan-ALDH1A inhibitors to assess whether broad spectrum ALDH1A inhibition is an effective adjunct to chemotherapy in this critical tumor subtype. Optimization of the CM39 scaffold, aided by metabolite ID and several new ALDH1A1 crystal structures, led to improved biochemical potencies, improved cellular ALDH inhibition in HGSOC cell lines, and substantial improvements in microsomal stability culminating in orally bioavailable compounds. We demonstrate that two compounds 68 and 69 are able to synergize with chemotherapy in a resistant cell line and patient-derived HGSOC tumor spheroids, indicating their suitability for future in vivo proof of concept experiments.

有强有力的证据表明，抑制一种或多种醛脱氢酶 1A (ALDH1A) 同种型可能对化疗耐药的卵巢癌和其他肿瘤类型有益。虽然之前的许多努力都集中在 ALDH1A1 选择性抑制剂的开发上，但最致命的卵巢癌亚型高级别浆液性 (HGSOC) 表现出 ALDH1A3 的表达升高。在此，我们报告了泛 ALDH1A 抑制剂的持续开发，以评估广谱 ALDH1A 抑制是否是这一关键肿瘤亚型中化疗的有效辅助手段。CM39 支架的优化，在代谢物 ID 和几种新的 ALDH1A1 晶体结构的帮助下，提高了生化效力，改善了 HGSOC 细胞系中的细胞 ALDH 抑制，微粒体稳定性的显着改善，最终产生口服生物可利用的化合物。我们证明了两种化合物68和69能够与耐药细胞系和患者来源的 HGSOC 肿瘤球体中的化学疗法协同作用，表明它们适用于未来的体内概念验证实验。