DNA fragmentation induced by all‐trans retinoic acid and its steroidal analogue EA‐4 in C₂C₁₂ mouse and HL‐60 human leukemic cells in vitro

Abstract

We have recently shown that retinoic acid induces micronucleation mainly via chromosome breakage (Alakhras et al. Cancer Lett 2011; 306: 15-26). To further study retinoic acid clastogenicity and evaluate DNA damaging potential we investigated the ability of (a) all-trans retinoic acid and its steroidal analogue EA-4 to induce DNA fragmentation by using Comet assay under alkaline unwinding and neutral condition electrophoresis, and (b) the retinoids under study to induce small (0-1 kb) DNA fragments. Two cell lines, C2C12 mouse cells and HL-60 human leukemic cells were used in this study. We found that all-trans retinoic acid and its steroidal analogue EA-4 (a) provoke DNA migration due to DNA fragmentation as it is shown by the increased values of Comet parameters, and (b) induce significantly small-size fragmented genomic DNA as indicated by the quantification of necrotic/apoptotic small DNA segments in both cell systems. A different response between the two cell lines was observed in relation to retinoid ability to increase the percentage of DNA in the tail as well as break DNA in to small fragments. Our findings confirm the ability of retinoic acid to provoke micronucleation by disrupting DNA into fragments, among which small pieces of double-stranded DNA up to 1 kb are identified.

All-Trans Retinoic Acid Modulates DNA Damage Response and the Expression of the VEGF-A and MKI67 Genes in ARPE-19 Cells Subjected to Oxidative Stress

“…ATRA was shown to exert its pro-apoptotic effect through the activation of the mitochondrial pathway [ 26 ]. The induction of apoptosis was associated with DNA fragmentation and cell cycle redistribution [ 26 , 27 ].…”

Fatty acid lithium salts from Cunninghamella echinulata have cytotoxic and genotoxic effects on HL‐60 human leukemia cells

“…The efficiency of FALS to induce damages on and/or to kill HL‐60 cells was compared to that of H 2 O 2 as, according to Alakhras et al. , this compound induces cell killing and DNA fragmentation, while according to Wagner et al. induces apoptotic and necrotic phenomena and DNA damage on HepG2 human hepatoma cells .…”

“…Therefore, in the present investigation, FALS derived from total lipids of Cunnighamella echinulata were used, instead of pure GLA, against HL-60 leukemic cells. The efficiency of FALS to induce damages on and/or to kill HL-60 cells was compared to that of H 2 O 2 as, according to Alakhras et al [43], this compound induces cell killing and DNA fragmentation, while according to Wagner et al [71] induces apoptotic and necrotic phenomena and DNA damage on HepG2 human hepatoma cells [72]. Actually in the present investigation it was found that treatment of HL-60 cells with H 2 O 2 at 100 μM resulted in cell death, while its cytotoxicity was not time dependent, at least for the concentration and treatment duration studied, in accordance with Benhusein et al [72], who reported similar observations working with HepG2 cancer kidney cells.…”

“…Cell culture establishment was achieved as recently referred . At least 24 h after culturing control cultures received fresh medium, while chemical‐treated cultures received fresh medium containing H 2 O 2 at 100 μM for 20, 40, and 60 min, or FALS at four final concentrations 5, 10, 15, and 20 μg/mL for 20 min.…”

“…The HL-60 is a human leukemic cell line (DSMZ, Braunschweig, Germany), derived from the peripheral blood leukocytes of untreated 36 years female with acute promyelocytic leukemia [41,42]. Cell culture establishment was achieved as recently referred [43]. At least 24 h after culturing control cultures received fresh medium, while chemical-treated cultures received fresh medium containing H 2 O 2 at 100 μM for 20, 40, and 60 min, or FALS at four final concentrations 5, 10, 15, and 20 μg/mL for 20 min.…”