Inhibition of NF-kappaB1 and NF-kappaB2 activation in prostate cancer cells treated with antibody against the carboxyl terminal domain of GRP78: effect of p53 upregulation.
Ligation of cancer cell surface GRP78 by activated alpha2-macroglobulin (alpha2M*) triggers pro-proliferative and anti-apoptotic signaling pathways. Cancer patients who develop autoantibodies to the alpha2M* binding site in GRP78 have a poor prognosis since these antibodies are receptor agonists. The NF-kappaB family of transcription factors induces expression of genes affecting cell growth and differentiation. NF-kappaB1 plays a major regulatory role in controlling innate immunity and inflammation, whereas NF-kappaB2 plays a greater role in cancer cell proliferation. Here we report that treatment of prostate cancer cells with antibody directed against the carboxyl terminal domain of GRP78 inhibits alpha2M*-induced activation of NF-kappaB2 by approximately 50% while exerting a lesser effect of approximately 20% on NF-kappaB1 activation. Treatment of these cells nearly abolished alpha2M*-induced activation of IKKalpha involved in the activation of NF-kappaB2. This antibody also suppressed alpha2M*-induced phosphorylation of IKKalpha, IKKalpha/beta, IkappaBalpha, and IkappaBbeta as well as levels of NIK. Antibody treatment of cancer cells elevated pro-apoptotic p21WAF and p27kip while reducing cyclin D1 levels. These studies demonstrate that antibody directed against the carboxyl terminal domain of GRP78 inhibits the pro-proliferative NF-kappaB signaling cascade in cancer cells.
Misra
U K
UK
Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA.
Kaczowka
S
S
Pizzo
S V
SV
D000912:Antibodies, Neoplasm / Q000494:pharmacology*; D001323:Autoantibodies / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D019938:Cyclin D1 / Q000378:metabolism; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D008297:Male; D052002:NF-kappa B p50 Subunit / Q000819:agonists / Q000037:antagonists & inhibitors*; D052003:NF-kappa B p52 Subunit / Q000819:agonists / Q000037:antagonists & inhibitors*; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D017434:Protein Structure, Tertiary; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D000511:alpha-Macroglobulins / Q000276:immunology / Q000378:metabolism
D000912:Antibodies, Neoplasm; D001323:Autoantibodies; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D052002:NF-kappa B p50 Subunit; D052003:NF-kappa B p52 Subunit; D016159:Tumor Suppressor Protein p53; D000511:alpha-Macroglobulins; D019938:Cyclin D1; D050760:Cyclin-Dependent Kinase Inhibitor p27