Influence of selected anti-cancer drugs on the induction of DNA double-strand breaks and changes in gene expression in human hepatoma HepG2 cells

Abstract

In chemotherapy, various anti-cancer drugs with different mechanisms of action are used and may represent different risk of undesirable delayed side effects in treated patients as well as in occupationally exposed populations. The aim of the present study was to evaluate genotoxic potential of four widely used anti-cancer drugs with different mechanisms of action: 5-fluorouracil (5-FU), cisplatin (CDDP) and etoposide (ET) that cause cell death by targeting DNA function and imatinib mesylate (IM) that inhibits targeted protein kinases in cancer cells in an experimental model with human hepatoma HepG2 cells. After 24 h of exposure all four anti-cancer drugs at non-cytotoxic concentrations induced significant increase in formation of DNA double strand breaks (DSBs), with IM being the least effective. The analysis of the changes in the expression of genes involved in the response to DNA damage (CDKN1A, GADD45A, MDM2), apoptosis (BAX, BCL2) and oncogenesis (MYC, JUN) showed that 5-FU, CDDP and ET upregulated the genes involved in DNA damage response, while the anti-apoptotic gene BCL2 and oncogene MYC were downregulated. On the contrary, IM did not change the mRNA level of the studied genes, showing different mechanism of action that probably does not involve direct interaction with DNA processing. Genotoxic effects of the tested anti-cancer drugs were observed at their therapeutic concentrations that may consequently lead to increased risk for development of delayed adverse effects in patients. In addition, considering the genotoxic mechanism of action of 5-FU, CDDP and ET an increased risk can also not be excluded in occupationally exposed populations. The results also indicate that exposure to 5-FU, CDDP and ET represent a higher risk for delayed effects such as cancer, reproductive effects and heritable disease than exposure to IM.

Analysis of Molecular Mechanisms of 5-Fluorouracil Induced Steatosis and Inflammation in Vitro and in Mice

“…5-FU was applied in a dose range not causing cellular injury to focus on direct, cell specific effects. The applied 5-FU doses were in line with previous studies of Novak et al [44] and Gajski et al [45], who also found that doses up to 250 µM are nontoxic for HepG2 cells. Also for analyzing the effect of 5-FU in primary human hepatocytes, a dose was chosen in accordance with previous studies showing that it does not affect hepatocellular viability [46] For in vivo analyses, we administered a single dose of 200 mg/kg 5-FU to mice.…”

Antiproliferative chromone derivatives induce K562 cell death through endogenous and exogenous pathways

“…Target chromone/furoxan hybrids (12a-d, 13a-d, 14a-d and 15ad) were evaluated for their inhibitory effects against five different human cancer cell lines (hepatoma HepG2, breast carcinoma MCF-7, colorectal carcinoma HCT-116, melanoma B16 and chronic myeloid leukaemia K562), with the reference fluorouracil (5-Fu) [63][64][65][66] . Meanwhile, the activities against the human normal hepatic L-02 cell line and peripheral blood mononuclear cells (PBMCs) were also evaluated since a potential anticancer drug candidate would be better to show selective cytotoxicity between malignant and normal cells.…”

Analysis of molecular mechanisms of 5-fluorouracil-induced steatosis and inflammationin vitroand in mice

“…The applied 5-FU doses were in line with previous studies of Novak et al . [ 44 ] and Gajski et al . [ 45 ], who also found that doses up to 250 μM are non-toxic for HepG2 cells.…”