Adriamycin resistance in HCC seriously hinders the treatment of patients, it is necessary to investigate the mechanisms. Autophagy is involved in adriamycin resistance and JNK2 is related to autophagy. However, whether JNK2 inducing drug resistance though autophagy is unknown. GL-V9, a new synthesized flavonoid derivative, has been proved of its anti-tumor effects. The aim of the study is to explore the role of JNK2-related autophagy on adriamycin-induced drug resistance and the effects of GL-V9 on reversing adriamycin resistance. We concluded that JNK2 played an important role in drug resistance induced by adriamycin. The high expression of JNK2 activated protective autophagy in Hep G2-DOXR cells under non-stress condition, which protected cells from drug attacking. Furthermore, we found that GL-V9 reversed adriamycin resistance by blocking the JNK2-related protective autophagy in HCC.
Aims TRAP1 is involved in metabolic reprogramming and promotes drug resistance. We aimed to explore whether a novel HSP90 inhibitor, C210, overcomes doxorubicin (DOX) resistance of quiescent breast cancer cells by targeting TRAP1. Methods Breast cancer cells were induced to quiescence by hypoxia and low glucose. The relationship of cell metabolism with HSP90 and TRAP1 was investigated by Western blotting, ECAR, OCR, mitochondrial complex activity, and proteomic analysis. The targets of C210 and their functions were analyzed by SPR and immunoprecipitation. The antitumor effect in vivo was investigated with mouse tumor model. Results In hypoxia and glucose deprivation, breast cancer cells exhibited elevated TRAP1 and an OXPHOS-enhanced quiescent phenotype. These cells were highly resistant to DOX but more sensitive to C210. C210 disrupted TRAP1's interaction with OXPHOS-associated client proteins, prompting proteasome-dependent degradation of these proteins, thereby reducing OCR, mitochondrial ATP production and resulting in selective elimination of the quiescent cancer cells by inducing mitochondrial apoptosis which could be reversed by exogenous ATP. Moreover, C210 targeted glycolytic, amino acid, and β-oxidation-associated proteome. C210 demonstrated promising in vivo anticancer efficacy which was particularly related to OXPHOS inhibition. Conclusions C210 eliminates DOX-resistant quiescent breast cancer cells by targeting TRAP1-dependent bioenergetics.
Aims To investigate the effect of 7- O -geranylquercetin (GQ), a derivative of quercetin (Q), on reversing drug resistance in breast cancer MCF-7/ADR cells and reveal the mechanisms related to P-glycoprotein (P-gp). Main methods Cell viability was determined by MTT assay. Accumulation of adriamycin (ADR) in cells was determined by confocal fluorescence microscope and microplate reader while that of rhodamine (Rh) was measured by flow cytometry. Expression levels of P-gp and MDR1 gene in cells were detected by western blot and Real-Time PCR, respectively. Molecular docking of GQ and Q with P-gp was conducted using AutoDock program. Xenograft model was established by inoculating MCF-7/ADR cells in BALB/c-nude mice. Tumor bearing mice were administered with ADR via tail vein injection and/or GQ (Q) by gavage. Expression levels of P-gp in tissues were detected by western blot and immunohistochemistry. Key findings GQ could reverse drug resistance of MCF-7/ADR cells to ADR. GQ inhibited the efflux of ADR by down-regulating the expression of P-gp protein and its encoding gene MDR1 in MCF-7/ADR cells. Molecular modeling showed that GQ matched with P-gp better than Q. GQ enhanced the antitumor effects of ADR and decreased the expression of P-gp in mice and its activities were higher than that of Q. GQ could reverse drug resistance of MCF-7/ADR cells by down-regulating the expression of P-gp in vitro and in vivo. Significances The reversal effect of GQ on P-gp-mediated drug resistance indicates its potential as a reversal agent for drug resistance in cancer chemotherapy.