Preferential recognition of peroxynitrite modified human DNA by circulating autoantibodies in cancer patients

详细信息    查看全文

• 作者：Safia Habib ; Moinuddin ; Asif Ali ; Rashid Ali
• 关键词：Cancer autoantibodies ; Reactive nitrogen species ; Peroxynitrite modified DNA ; DNA damage
• 刊名：Cellular Immunology
• 出版年：2009
• 出版时间：2009
• 年：2009
• 卷：254
• 期：2
• 页码：117-123
• 全文大小：1045 K

文摘

Peroxynitrite (ONOO⁻) has been vastly implicated in mutagenesis and cancer development. Present study probes the antigenicity of peroxynitrite damaged DNA (ONOO⁻–DNA) in cancer patients. Purified human placental DNA was damaged by the synergistic action of sodium nitroprusside (SNP) and Pyrogallol for 3 h at 37 °C. Binding characteristics of cancer autoantibodies as well as experimentally induced anti-peroxynitrite-DNA (anti-ONOO⁻–DNA) antibodies were assessed by ELISA and band shift assay. DNA modifications produced single strand breaks, decreased melting temperature (T_m), hyperchromicity in UV spectrum and decreased fluorescence intensity. The ONOO⁻–DNA induced high titre antibodies in experimental animals. Cancer autoantibodies exhibited enhanced binding with the modified DNA as compared to the native form. Lymphocyte DNA from cancer patients showed appreciable recognition of anti-ONOO⁻–DNA IgG as compared to the DNA from healthy subjects. The peroxynitrite modified DNA presents unique epitopes which may be one of the factors for the autoantibody induction in cancer patients.