Isoflavones and gamma irradiation inhibit cell growth in human salivary gland cells.
We studied the effects of isoflavones and irradiation on cell cycle in a human salivary gland cell line (HSG). Genistein and a soy isoflavone conjugate (NS) inhibited DNA synthesis. Cells deconjugated the glucoside form of isoflavones in NS to the aglycones genistein and daidzein. NS, genistein and IR increased phosphorylation of p53 and p21 CIP1 at serine 15 (phos-p53). Irradiation and NS also increased levels of p21 CIP1. In a cologenic survival assay, cells in log phase growth had high radio-sensitivity with 2 Gy causing a reduction in survival (SF2=0.45).


CONCLUSIONS
isoflavones and radiation may interact to sensitize cancer cells to radiation.
Katz
J
J
Department of Oral Maxillofacial Surgery and Diagnostic Sciences, University of Florida, PO Box 100414, Gainesville, FL 32610-0414, USA. jkatz@dental.ufl.edu
Blake
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E
Medrano
T A
TA
Sun
Y
Y
Shiverick
K T
KT
D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000032:analysis; D050760:Cyclin-Dependent Kinase Inhibitor p27; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D005720:Gamma Rays; D019833:Genistein / Q000494:pharmacology*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000032:analysis; D007529:Isoflavones / Q000494:pharmacology*; D010766:Phosphorylation; D012469:Salivary Glands / Q000166:cytology / Q000187:drug effects* / Q000528:radiation effects; D013025:Glycine max / Q000737:chemistry*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis; D014810:Vitamin E / Q000494:pharmacology
C493956:CDKN1A protein, human; C436291:CDKN1B protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D047908:Intracellular Signaling Peptides and Proteins; D007529:Isoflavones; D016159:Tumor Suppressor Protein p53; D014810:Vitamin E; D050760:Cyclin-Dependent Kinase Inhibitor p27; D019833:Genistein