Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

A synthetic polyvalent ligand for α5β1 integrin activates components of the urothelial carcinoma cell response to bacillus Calmette-Guérin. J Urol 2013 Mar;189(3):1104-9 PMID: 22999999

Pubmed ID





PURPOSE: Prior study has shown that bacillus Calmette-Guérin binds to and cross-links α5β1 integrins present on the surface of urothelial carcinoma cells. Antibody mediated cross-linking of α5β1 integrins can reproduce signal transduction, gene transactivation and phenotypic changes, similar to those observed in response to bacillus Calmette-Guérin. We evaluated the effect of a synthetic polyvalent ligand for α5β1 on these elements of the tumor response to bacillus Calmette-Guérin.

MATERIALS AND METHODS: The consensus α5β1 integrin binding tripeptide RGD was linked to a MAP8 backbone to result in an octavalent construct targeting α5β1 integrin. RGD-MAP8 was used to determine its effect on signaling pathway activation (nuclear factor-κB, NRF2 and CEBP), gene expression (p21, interleukin-6 and 8, CXCL1, CXCL2 and CCL20) and cytotoxicity (trypan blue exclusion and HMGB1 release) in human urothelial carcinoma cells. Results were compared to those of treatment with bacillus Calmette-Guérin or the missense peptide GRD-MAP8.

RESULTS: The RDG-MAP8 construct significantly increased nuclear factor-κB signaling and p21 expression relative to controls. Compared to bacillus Calmette-Guérin treatment, only p21 expression was comparable for cells treated with RGD-MAP8, averaging 70% of bacillus Calmette-Guérin induced expression. RGD-MAP8 failed to have a significant effect on CEBP or NRF2 activation, gene expression or cell viability.

CONCLUSIONS: Intracellular signaling, gene transactivation and phenotypic changes in response to RGD-MAP8 were qualitatively and quantitatively different than those observed in response to bacillus Calmette-Guérin. Results suggest that while α5β1 integrin cross-linking contributes to the bacillus Calmette-Guérin response, it alone is insufficient to duplicate the full spectrum of bacillus Calmette-Guérin induced changes in urothelial carcinoma cell biology.

Author List

Chen F, Zhang G, Cao Y, Wakim B, See WA


William A. See MD Chair, Professor in the Urologic Surgery department at Medical College of Wisconsin


2-s2.0-84873725495   2 Citations

MESH terms used to index this publication - Major topics in bold

Adjuvants, Immunologic
BCG Vaccine
Carcinoma, Transitional Cell
Cell Line, Tumor
DNA, Neoplasm
Enzyme-Linked Immunosorbent Assay
Flow Cytometry
Gene Expression Regulation, Neoplastic
Integrin alpha5beta1
Reverse Transcriptase Polymerase Chain Reaction
Signal Transduction
Urinary Bladder Neoplasms
jenkins-FCD Prod-336 69ef4a6b262d135130251597d5d39873903802b5