Abstract
Background: Multidrug-resistant tumor cells have special drug detoxification/inactivation mechanisms. The terminal amino groups of the polyamidoamine (PAMAM-NH2), which is cytotoxic to tumor sensitive cells, may have no cytotoxicity in tumor resistant cells with a mechanism different from tumor sensitive cells.
Objective: This study aimed to investigate the cytotoxic effects of PAMAM-G4-NH2 on human multidrug- resistant breast cancer cells (MCF-7/ADR cells) and identify the possible molecular mechanisms.
Methods: The cytotoxicity of PAMAM-G4-NH2 (10-1000 μg/mL) against MCF-7 and MCF-7/ADR cells was detected. Then, MCF-7 and MCF-7/ADR cells were treated with PAMAM-G4-NH2 (10, 100 and 1000 μg/mL), and apoptosis, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), activities of caspase-3, -8 and -9 and cell cycle distribution were determined.
Results: Within 48 h, the cell viabilities in MCF-7/ADR cells after treatment with PAMAM-G4-NH2 were significantly higher than that in MCF-7 cells in the concentration range of 200-500 μg/mL (P < 0.05). Viabilities of MCF-7/ADR cells treated with PAMAM-G4-OH and PAMAM-G4-COOH for 48 and 72 h were much higher than that of MCF-7/ADR cells treated with PAMAM-G4-NH2. Treated with high concentration (1000 μg/mL) of PAMAM-G4-NH2 for 24 h, the apoptosis ratio, ROS levels, as well as caspase-3 and -9 activities in MCF-7 and MCF-7/ADR cells increased, while MMP decreased, and the cells were arrested in the G0/G1 phase.
Conclusion: PAMAM-G4-NH2 induced concentration-dependent cytotoxicity in MCF-7/ADR cells via G0/G1 arrest, and acted through h the mitochondria-dependent apoptotic pathway, which was similar to those in tumor sensitive cell, MCF-7 cells. The results suggest that PAMAM-G4-NH2, instead of PAMAM-G4-OH and PAMAM-G4-COOH, can be used as a carrier for drug delivery, concomitantly, it can also induce apoptosis in multidrug-resistant cancer cells in combination with the loaded drug through multiple apoptotic pathways.
Keywords: PAMAM-G4-NH2 dendrimer, multidrug-resistant tumor, cytotoxicity, apoptosis, cell cycle, mitochondrial pathway
Graphical Abstract
[http://dx.doi.org/10.1016/j.ijpharm.2018.05.045] [PMID: 29787895]
[http://dx.doi.org/10.1038/nrc3599] [PMID: 24060863]
[http://dx.doi.org/10.1016/j.biomaterials.2013.08.032] [PMID: 24021757]
[http://dx.doi.org/10.2217/nnm-2016-0252] [PMID: 27780403]
[http://dx.doi.org/10.1016/j.biotechadv.2013.06.004] [PMID: 23800690]
[http://dx.doi.org/10.1016/j.addr.2013.08.004] [PMID: 23973912]
[http://dx.doi.org/10.1016/j.progpolymsci.2013.07.005]
[http://dx.doi.org/10.3390/molecules22091401] [PMID: 28832535]
[http://dx.doi.org/10.3390/pharmaceutics11070351] [PMID: 31323863]
[http://dx.doi.org/10.1248/jhs.55.169]
[http://dx.doi.org/10.2147/IJN.S106418] [PMID: 27536106]
[http://dx.doi.org/10.1016/j.bbrc.2020.04.064] [PMID: 32446354]
[http://dx.doi.org/10.3390/pharmaceutics4010130] [PMID: 24300184]
[http://dx.doi.org/10.1016/j.ijpharm.2020.119993] [PMID: 33086089]
[http://dx.doi.org/10.1016/j.addr.2005.09.019] [PMID: 16297497]
[http://dx.doi.org/10.1098/rspa.2009.0448]
[http://dx.doi.org/10.2131/jts.41.351] [PMID: 27193728]
[http://dx.doi.org/10.1016/S0378-5173(02)00623-3] [PMID: 12550802]
[http://dx.doi.org/10.1021/bm900683r] [PMID: 19924846]
[http://dx.doi.org/10.1016/j.addr.2011.09.010] [PMID: 21983078]
[http://dx.doi.org/10.1248/cpb.59.63] [PMID: 21212549]
[http://dx.doi.org/10.1016/j.biomaterials.2013.09.006] [PMID: 24094823]
[http://dx.doi.org/10.1002/(SICI)1097-0320(19960601)24:2<131:AID-CYTO5>3.0.CO;2-M] [PMID: 8725662]
[http://dx.doi.org/10.1083/jcb.59.3.766] [PMID: 4128323]
[http://dx.doi.org/10.1083/jcb.71.1.172] [PMID: 61966]
[http://dx.doi.org/10.1038/284555a0] [PMID: 6245367]
[http://dx.doi.org/10.1016/j.toxlet.2009.07.018] [PMID: 19643170]
[http://dx.doi.org/10.1021/acs.molpharmaceut.5b00568] [PMID: 26393405]
[http://dx.doi.org/10.1021/acs.molpharmaceut.5b00129] [PMID: 25945733]
[http://dx.doi.org/10.3390/molecules181113769] [PMID: 24213655]
[http://dx.doi.org/10.2174/0929867323666160106151428] [PMID: 26063498]