Nitric oxide initiates progression of human melanoma via a feedback loop mediated by apurinic/apyrimidinic endonuclease-1/redox factor-1, which is inhibited by resveratrol.
It is well recognized that nitric oxide (NO) is involved in tumor progression, including melanoma. Measurement of proliferative and metastatic capacity by MTS and Matrigel invasion assays, respectively, was done and showed that NO-treated melanoma cells exhibited a higher capacity compared with control, especially metastatic Lu1205 cells. Apurinic/apyrimidinic endonuclease-1/redox factor-1 (APE/Ref-1) is a multifunctional protein and its role in tumor biology has attracted considerable attention. To determine whether APE/Ref-1 plays a role in mediating NO stimulation of melanoma progression, we investigated the effect of DETA/NO on levels of APE/Ref-1 and related downstream targets [activator protein-1 (AP-1)/JunD, matrix metalloproteinase-1 (MMP-1), Bcl-2, and inducible nitric oxide synthase (iNOS)] by Western blot and reverse transcription-PCR analysis. Following DETA/NO treatment, APE/Ref-1 and other downstream molecules were induced. Knockdown of APE/Ref-1 or AP-1/JunD by specific small interfering RNA markedly reversed the induction by NO stress of target proteins. These results present evidence for the existence of a functional feedback loop contributing to progression and metastasis of melanoma cells. Resveratrol has been shown to be an APE/Ref-1 inhibitor and significant decreases in AP-1/JunD, MMP-1, Bcl-2, and iNOS protein levels occurred after exposure to resveratrol. This phenolic antioxidant may be an appropriate choice for combining with other compounds that develop resistance by up-regulation of these molecules.
Yang
Zhen
Z
Chao Family Comprehensive Cancer Center, University of California-Irvine School of Medicine, Orange, California, USA.
Yang
Sun
S
Misner
Bobbye J
BJ
Chiu
Rita
R
Liu
Feng
F
Meyskens
Frank L
FL
D000972:Antineoplastic Agents, Phytogenic / Q000378:metabolism / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000378:metabolism / Q000502:physiology*; D018450:Disease Progression; D025461:Feedback, Physiological; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008545:Melanoma / Q000378:metabolism / Q000473:pathology*; D008954:Models, Biological; D009362:Neoplasm Metastasis; D009569:Nitric Oxide / Q000378:metabolism*; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology*; D018808:Transcription Factor AP-1 / Q000502:physiology
D000972:Antineoplastic Agents, Phytogenic; D013267:Stilbenes; D018808:Transcription Factor AP-1; D009569:Nitric Oxide; C085108:APEX1 protein, human; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D000077185:Resveratrol