Our previous work found that DMH1 (4-[6-(4-isopropoxyphenyl)pyrazolo [1,5-a]pyrimidin-3-yl]quinoline) was a novel autophagy inhibitor. Here, we aimed to investigate the effects of DMH1 on chemotherapeutic drug-induced autophagy as well as the efficacy of chemotherapeutic drugs in different cancer cells. We found that DMH1 inhibited tamoxifen- and cispcis-diaminedichloroplatinum (II) (CDDP)-induced autophagy responses in MCF-7 and HeLa cells, and potentiated the anti-tumor activity of tamoxifen and CDDP for both cells. DMH1 inhibited 5-fluorouracil (5-FU)-induced autophagy responses in MCF-7 and HeLa cells, but did not affect the anti-tumor activity of 5-FU for these two cell lines. DMH1 itself did not induce cell death in MCF-7 and HeLa cells, but inhibited the proliferation of these cells. In conclusion, DMH1 inhibits chemotherapeutic drug-induced autophagy response and the enhancement of efficacy of chemotherapeutic drugs by DMH1 is dependent on the cell sensitivity to drugs.

中文翻译：

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DMH1（4- [6-（4-异丙氧基苯基）吡唑并[1,5-a]嘧啶-3-基]喹啉）抑制化疗药物诱导的自噬。

我们以前的工作发现DMH1（4- [6-（4-异丙氧基苯基）吡唑并[1,5-a]嘧啶-3-基]喹啉）是一种新型的自噬抑制剂。在这里，我们旨在研究DMH1对化疗药物诱导的自噬的影响以及化疗药物在不同癌细胞中的功效。我们发现DMH1抑制他莫昔芬和顺式二胺二氯铂（II）（CDDP）诱导MCF-7和HeLa细胞中的自噬反应，并增强了他莫昔芬和CDDP对这两种细胞的抗肿瘤活性。DMH1抑制5-氟尿嘧啶（5-FU）诱导的MCF-7和HeLa细胞自噬反应，但不影响5-FU对这两种细胞系的抗肿瘤活性。DMH1本身不会在MCF-7和HeLa细胞中诱导细胞死亡，但会抑制这些细胞的增殖。综上所述，