Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a promising target for anticancer therapy due to its ability to counter the effects topoisomerase 1 (Top1) poison, such as topotecan, thus, decreasing their efficacy. Compounds containing adamantane and monoterpenoid residues connected via 1,2,4-triazole or 1,3,4-thiadiazole linkers were synthesized and tested against Tdp1. All the derivatives exhibited inhibition at low micromolar or nanomolar concentrations with the most potent inhibitors having IC50 values in the 0.35–0.57 µM range. The cytotoxicity was determined in the HeLa, HCT-116 and SW837 cancer cell lines; moderate CC50 (µM) values were seen from the mid-teens to no effect at 100 µM. Furthermore, citral derivative 20c, α-pinene-derived compounds 20f, 20g and 25c, and the citronellic acid derivative 25b were found to have a sensitizing effect in conjunction with topotecan in the HeLa cervical cancer and colon adenocarcinoma HCT-116 cell lines. The ligands are predicted to bind in the catalytic pocket of Tdp1 and have favorable physicochemical properties for further development as a potential adjunct therapy with Top1 poisons.
酪氨酸-DNA磷酸二酯酶1(Tdp1)是抗癌治疗的一个有前途的靶点,因为它能够对抗拓扑异构酶1(Top1)毒素的影响,如托泊替康(topotecan),从而降低它们的疗效。含有金刚烷和单萜类残基,通过1,2,4-三唑或1,3,4-噻二唑连接剂连接的化合物已经合成并对Tdp1进行了测试。所有衍生物在低微摄或纳摄浓度下表现出抑制作用,其中最有效的抑制剂的IC50值在0.35-0.57 µM范围内。细胞毒性在HeLa、HCT-116和SW837癌细胞系中进行了测定;中等CC50(µM)值从中十几到100 µM无效不等。此外,在HeLa宫颈癌和结肠腺癌HCT-116细胞系中,柠檬醛衍生物20c,α-蒎烯衍生物20f、20g和25c,以及柠檬醛酸衍生物25b被发现与托泊替康联用具有增敏作用。 预测这些配体将结合在Tdp1的催化口袋中,并具有有利的物理化学性质,可进一步作为与Top1毒素联合治疗的潜在辅助疗法进行开发。