A Locked, Dimeric CXCL12 Variant Effectively Inhibits Pulmonary Metastasis of CXCR4-Expressing Melanoma Cells Due to Enhanced Serum Stability
- 1 November 2012
- journal article
- Published by American Association for Cancer Research (AACR) in Molecular Cancer Therapeutics
- Vol. 11 (11), 2516-2525
- https://doi.org/10.1158/1535-7163.mct-12-0494
Abstract
The CXC chemokine receptor-4 (CXCR4) plays a critical role in cancer by positively regulating cancer cell metastasis and survival. We previously showed that high concentrations of the CXCR4 ligand, wild-type CXCL12 (wtCXCL12), could inhibit colorectal cancer metastasis in vivo, and we have hypothesized that wtCXCL12 dimerizes at high concentration to become a potent antagonist of CXCR4. To address this hypothesis, we engineered a covalently locked, dimeric variant of CXCL12 (CXCL122). Herein, we show that CXCL122 can not only inhibit implantation of lung metastasis of CXCR4-B16-F10 melanoma cells more effectively than AMD3100, but that CXCL122 also blocks the growth of established pulmonary tumors. To identify a basis for the in vivo efficacy of CXCL122, we conducted Western blot analysis and ELISA analyses, which revealed that CXCL122 was stable for at least 12 hours in serum, whereas wtCXCL12 was quickly degraded. CXCL122 also maintained its antagonist properties in in vitro chemotaxis assays for up to 24 hours in serum, whereas wtCXCL12 was ineffective after 6 hours. Heat-inactivation of serum prolonged the stability and function of wtCXCL12 by more than 6 hours, suggesting enzymatic degradation as a possible mechanism for wtCXCL12 inactivation. In vitro analysis of amino-terminal cleavage by enzymes dipeptidylpeptidase IV (DPPIV/CD26) and matrix metalloproteinase-2 (MMP-2) resulted in 25-fold and 2-fold slower degradation rates, respectively, of CXCL122 compared with wtCXCL12. In summary, our results suggest CXCL122 possesses greater potential as an antimetastatic drug as compared with AMD3100 or wtCXCL12, potentially due to enhanced serum stability in the presence of N-terminal degrading enzymes. Mol Cancer Ther; 11(11); 2516–25. ©2012 AACR.Keywords
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This publication has 39 references indexed in Scilit:
- Inhibition of stromal CXCR4 impairs development of lung metastasesCancer Immunology, Immunotherapy, 2012
- Monomeric and dimeric CXCL12 inhibit metastasis through distinct CXCR4 interactions and signaling pathwaysProceedings of the National Academy of Sciences of the United States of America, 2011
- C-X-C receptor type 4 promotes metastasis by activating p38 mitogen-activated protein kinase in myeloid differentiation antigen (Gr-1)-positive cellsProceedings of the National Academy of Sciences of the United States of America, 2010
- CXCL12 / CXCR4 / CXCR7 chemokine axis and cancer progressionCancer and Metastasis Reviews, 2010
- DC-HIL/Glycoprotein Nmb Promotes Growth of Melanoma in Mice by Inhibiting the Activation of Tumor-Reactive T CellsCancer Research, 2010
- High expression of CXCR4 may predict poor survival in resected pancreatic adenocarcinomaBritish Journal of Cancer, 2009
- Structural Basis of CXCR4 Sulfotyrosine Recognition by the Chemokine SDF-1/CXCL12Science Signaling, 2008
- The Novel CXCL12γ Isoform Encodes an Unstructured Cationic Domain Which Regulates Bioactivity and Interaction with Both Glycosaminoglycans and CXCR4PLOS ONE, 2007
- Clinical utilization of chemokines to combat cancer: the double-edged swordExpert Review of Vaccines, 2007
- New functions for the matrix metalloproteinases in cancer progressionNature Reviews Cancer, 2002