A comparative study of the aneugenic and polyploidy-inducing effects of fisetin and two model Aurora kinase inhibitors

Abstract

Fisetin, a plant flavonol commonly found in fruits, nuts and vegetables, is frequently added to nutritional supplements due to its reported cardioprotective, anti-carcinogenic and antioxidant properties. Earlier reports from our laboratory and others have indicated that fisetin has both aneugenic and clastogenic properties in cultured cells. More recently, fisetin has also been reported to target Aurora B kinase, a Ser/Thr kinase involved in ensuring proper microtubule attachment at the spindle assembly checkpoint, and an enzyme that is overexpressed in several types of cancer. Here we have further characterized the chromosome damage caused by fisetin and compared it with that induced by two known Aurora kinase inhibitors, VX-680 and ZM-447439, in cultured TK6 cells using the micronucleus assay with CREST staining as well as a flow cytometry-based assay that measures multiple types of numerical chromosomal aberrations. The three compounds were highly effective in inducing aneuploidy and polyploidy as evidenced by increases in kinetochore-positive micronuclei, hyperdiploidy, and polyploidy. With fisetin, however, the latter two effects were most significantly observed only after cells were allowed to overcome a cell cycle delay, and occurred at higher concentrations than those induced by the other Aurora kinase inhibitors. Modest increases in kinetochore-negative micronuclei were also seen with the model Aurora kinase inhibitors. These results indicate that fisetin induces multiple types of chromosome abnormalities in human cells, and indicate a need for a thorough investigation of fisetin-augmented dietary supplements.

Genotoxic mode of action predictions from a multiplexed flow cytometric assay and a machine learning approach

“…The statistical model produced high aneugen probability scores that abruptly switched to high clastogen scores, the latter only occurring at concentrations that exceeded our cytotoxicity limit. It is not clear whether these were spurious results associated with overt toxicity, or whether they were related to observations made by Eastmond and colleagues who reported that fisetin is aneugenic at low concentrations, with clastogenic activity evident at higher concentrations [Olaharski et al, ; Gollapudi et al, ].…”

Exploring the molecular targets of dietary flavonoid fisetin in cancer

“…As a mechanism for these mitotic errors, Aurora B kinase was identified as a direct target of fisetin since Aurora B activity was significantly reduced by fisetin treatment [52]. Effects of fisetin on chromosome damage were investigated by Gollapudi et al [53] and compared with two known Aurora kinase inhibitors, VX-680 and ZM-447439. Fisetin treatment of human lymphoblastoid TK6 cells resulted in induction of aneuploidy and polyploidy as indicated by increase in kinetochore-positive micronuclei, hyperdiploidy, and polyploidy.…”

“…Fisetin treatment of human lymphoblastoid TK6 cells resulted in induction of aneuploidy and polyploidy as indicated by increase in kinetochore-positive micronuclei, hyperdiploidy, and polyploidy. These observations suggested that fisetin could induce multiple types of chromosomal abnormalities in human cells and warranted caution in the use of fisetin containing products [53]. …”

Classification of in vitro genotoxicants using a novel multiplexed biomarker assay compared to the flow cytometric micronucleus test

“…Another reason for this observation could be the timing to monitor polyploidy. Thus, in a previous study using a recovery time of 12 hr after 24 hr continuous treatment, an optimal polyploidy response by the aneugenic compound fisetin was reported [Gollapudi et al, ].…”