Combined treatment with vitamin B12b and ascorbic acid causes in vitro DNA degradation in tumor cells.
Incubation of Ehrlich ascites carcinoma and HEp-2 human epidermoid laryngeal carcinoma cells with hydroxycobalamin (vitamin B12b) and ascorbic acid induced generation and accumulation of double-stranded DNA fragments (23,000 b.p. and longer) in cells. The same vitamins alone in the same concentrations produced no such effects. DNA degradation in HEp-2 cells caused by long-term (4 h) incubation with 5-25 microM hydroxycobalamin and ascorbic acid (1:10-1:40 molar ratio) at 37 degrees C was comparable with that induced by gamma-irradiation in a dose of 150 Gy at 4 degrees C.
Medvedev
A I
AI
Laboratory of Cell Biochemistry and Bioenergetics, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino.
Akatov
V S
VS
Kreshchenko
N D
ND
Solov'eva
M E
ME
Leshchenko
V V
VV
Lezhnev
E I
EI
Yakubovskaya
R I
RI
D001205:Ascorbic Acid / Q000494:pharmacology*; D004249:DNA Damage; D004273:DNA, Neoplasm / Q000187:drug effects*; D003851:Deoxyribonucleases / Q000494:pharmacology*; D004357:Drug Synergism; D006801:Humans; D006879:Hydroxocobalamin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D004273:DNA, Neoplasm; D003851:Deoxyribonucleases; D001205:Ascorbic Acid; D006879:Hydroxocobalamin