[Effect of low-intensity microwave of on mitomycin C-induced genotoxicity in vitro].
OBJECTIVE
To study that low-intensity microwave whether or not enhances the genotoxic effects of mitomycin C(MMC) on human lymphocytes.


METHODS
Single strand DNA breaks and chromosomal aberrations were measured by comet assay and cytokinesis-blocked micronucleus(CBMN) test in vitro when human lymphocytes were exposed to 2,450-MHz microwave (5.0 mW/cm2) alone and in combination with mitomycin C.


RESULTS
In the comet assay, the average comet lengths of microwave group[(29.1 +/- 8.1) micron in male and (25.9 +/- 7.5) micron in female] were not significantly different from those of control groups [(26.3 +/- 6.6) and (24.1 +/- 4.3) micron respectively] (P > 0.05). The average comet lengths of MMC group(0.0125, 0.0250, 0.0500, 0.1000 microgram/ml) were significantly longer than those of control groups (P < 0.01) and were increased with the dose of MMC. The average comet lengths of microwave combined with MMC (MW + MMC) also were increased with the doses of MMC and were significantly longer than those of control groups (P < 0.01). When MMC was > or = 0.0250 microgram/ml, microwave and MMC synergistically increased the single strand DNA breaks. In the micronucleus test, the average micronucleus rates of microwave groups were not higher than those of control groups (P > 0.05). The average micronucleus rates of MMC groups and MW + MMC groups were significantly higher than those of control groups (P < 0.01) when MMC was > or = 0.0500 microgram/ml. The average micronucleus rates of MW + MMC groups seemed higher than those of corresponding MMC groups, however the difference was not significant (P > 0.05).


CONCLUSIONS
Low-intensity(2,450-MHz) microwave did not induce DNA and chromosome damages on human lymphocytes, but enhanced the effects of DNA breaks induced by MMC.
Zhang
Meibian
M
Institute of Occupational Health and Environmental Health, School of Medicine, Zhejiang University, Hangzhou 310031, China.
Lu
Deqiang
D
He
Jiliang
J
Jin
Lifen
L
D002869:Chromosome Aberrations; D020552:Comet Assay; D053904:DNA Breaks, Single-Stranded; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000528:radiation effects* / Q000648:ultrastructure; D008297:Male; D048629:Micronuclei, Chromosome-Defective; D008872:Microwaves / Q000009:adverse effects*; D016685:Mitomycin / Q000633:toxicity*
D016685:Mitomycin