Cytotoxicity of aloe-emodin towards several drug sensitive cells and their resistant counterparts

Cancer is one of the leading causes of death in the world. Despite there are notable improvements in cancer in the past few decades, many cancer patients still cannot be cured due to the development of multi drug resistance (MDR) [1]. Anthraquinones were shown to inhibit tumor growth on various cell lines in previous studies [2,3]. Main anthraquinone aglycons are significant due to their structural similarities to anthracyclines well established anticancer drugs. Therefore aloe-emodin was searched on various cell lines including drug-sensitive CCRF-CEM and multidrug resistant P-glycoprotein-over-expressing CEM/ADR5000 leukemia cells, MDA-MB-231-pcDNA3 breast cancer cells and their transfectant subline MDA-MB-231-BCRP clone 23, HCT116 (p53^+/+) colon cancer cells and their knockout clone HCT116 (p53^-/-), U87.MG glioblastoma multiform cells and their transfectant subline U87.MGΔEGFR as well as HEK293 human embryonic kidney cells transfected with or without a cDNA for ABCB5. The IC₅₀ values ranged from 21.20µM to 37.32µM for drug-sensitive and wild-type cell lines. For drug-resistant and transfected sublines, IC₅₀ values were ranged from 14.68µM to 66.31µM. Collateral sensitivity (hypersensitivity) to aloe-emodin was observed in HCT116 (p53^-/-) knockout cells (0.69 fold). Aloe-emodin having a notable cytotoxicity on few cancer cells needs to be conducted further researches on to clarify the background mechanisms behind its cytotoxicity.

This study was supported by The Scientific and Technological Research Council of Turkey (TÜBITAK) 2214-A scholarship.

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