beta-Actin-binding Complementarity-determining Region 2 of Variable Heavy Chain from Monoclonal Antibody C7 Induces Apoptosis in Several Human Tumor Cells and Is Protective against Metastatic Melanoma

Author(s):Show less -

Arruda, Denise C. ^[1] ; Santos, Luana C. P. ^[1] ; Melo, Filipe M. ^[1] ; Pereira, Felipe V. ^[1] ; Figueiredo, Carlos R. ^[1] ; Matsuo, Alisson L. ^{[1, 2]} ; Mortara, Renato A. ^[3] ; Juliano, Maria A. ^[4] ; Rodrigues, Elaine G. ^[1] ; Dobroff, Andrey S. ^[5] ; Polonelli, Luciano ^[6] ; Travassos, Luiz R. ^{[1, 2]}

Affiliation

^[1] Univ Fed Sao Paulo UNIFESP, Unidade Oncol Expt UNONEX, BR-04023062 Sao Paulo - Brazil

^[2] Recepta Biopharma, BR-04533014 Sao Paulo - Brazil

^[3] Univ Fed Sao Paulo UNIFESP, Div Parasitol, BR-04023062 Sao Paulo - Brazil

^[4] Univ Fed Sao Paulo UNIFESP, Dept Biophys, BR-04023062 Sao Paulo - Brazil

^[5] Univ Texas MD Anderson Canc Ctr, David H Koch Ctr, Houston, TX 77030 - USA

^[6] Univ Parma, I-43121 Parma - Italy

• Document type: Journal article
• Source: Journal of Biological Chemistry; v. 287, n. 18, p. 14912-14922, APR 27 2012.
• Web of Science Citations: 25

Abstract

Complementarity-determining regions (CDRs) from monoclonal antibodies tested as synthetic peptides display anti-infective and antitumor activities, independent of the specificity of the native antibody. Previously, we have shown that the synthetic peptide C7H2, based on the heavy chain CDR 2 from monoclonal antibody C7, a mAb directed to a mannoprotein of Candida albicans, significantly reduced B16F10 melanoma growth and lung colony formation by triggering tumor apoptosis. The mechanism, however, by which C7H2 induced apoptosis in tumor cells remained unknown. Here, we demonstrate that C7H2 interacts with components of the tumor cells cytoskeleton, being rapidly internalized after binding to the tumor cell surface. Mass spectrometry analysis and in vitro validation revealed that beta-actin is the receptor of C7H2 in the tumor cells. C7H2 induces beta-actin polymerization and F-actin stabilization, linked with abundant generation of superoxide anions and apoptosis. Major phenotypes following peptide binding were chromatin condensation, DNA fragmentation, annexin V binding, lamin disruption, caspase 8 and 3 activation, and organelle alterations. Finally, we evaluated the cytotoxic efficacy of C7H2 in a panel of human tumor cell lines. All tumor cell lines studied were equally susceptible to C7H2 in vitro. The C7H2 amide without further derivatization significantly reduced lung metastasis of mice endovenously challenged with B16F10-Nex2 melanoma cells. No significant cytotoxicity was observed toward nontumorigenic cell lines on short incubation in vitro or in naive mice injected with a high dose of the peptide. We believe that C7H2 is a promising peptide to be developed as an anticancer drug. (AU)

• FAPESP's process: 06/50634-2 - Peptides and peptidases: biological activities in infectious diseases and cancer
• Grantee: Luiz Rodolpho Raja Gabaglia Travassos
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 10/51423-0 - Bioactive peptides and peptidases: biological and immunobiological activities in infectious diseases and cancer
• Grantee: Luiz Rodolpho Raja Gabaglia Travassos
• Support Opportunities: Research Projects - Thematic Grants