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Transforming growth factor β signaling overcomes dasatinib resistance in lung cancer.

Gordian E, Li J, Pevzner Y, Mediavilla-Varela M, Luddy K, Ohaegbulam K, Daniel KG, Haura EB, Muñoz-Antonia T - PLoS ONE (2014)

Bottom Line: As a result, TKIs often developed for a specific purpose have been found to act on other targets.We found that dasatinib treatment alone had very little effect; however, when NSCLC cell lines were treated with a combination of TGFβ and dasatinib, apoptosis was induced.Knockdown of the expression of Smad3 using Smad3 siRNA also resulted in a decrease in BIM protein, suggesting that TGFβ-1 + dasatinib-induced apoptosis is mediated by Smad3 regulation of BIM.

View Article: PubMed Central - PubMed

Affiliation: Molecular Oncology Program, H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida 33612, United States of America.

ABSTRACT
Lung cancer is the second most common cancer and the leading cause of cancer-related deaths. Despite recent advances in the development of targeted therapies, patients with advanced disease remain incurable, mostly because metastatic non-small cell lung carcinomas (NSCLC) eventually become resistant to tyrosine kinase inhibitors (TKIs). Kinase inhibitors have the potential for target promiscuity because the kinase super family is the largest family of druggable genes that binds to a common substrate (ATP). As a result, TKIs often developed for a specific purpose have been found to act on other targets. Drug affinity chromatography has been used to show that dasatinib interacts with the TGFβ type I receptor (TβR-I), a serine-threonine kinase. To determine the potential biological relevance of this association, we studied the combined effects of dasatinib and TGFβ on lung cancer cell lines. We found that dasatinib treatment alone had very little effect; however, when NSCLC cell lines were treated with a combination of TGFβ and dasatinib, apoptosis was induced. Combined TGFβ-1 + dasatinib treatment had no effect on the activity of Smad2 or other non-canonical TGFβ intracellular mediators. Interestingly, combined TGFβ and dasatinib treatment resulted in a transient increase in p-Smad3 (seen after 3 hours). In addition, when NSCLC cells were treated with this combination, the pro-apoptotic protein BIM was up-regulated. Knockdown of the expression of Smad3 using Smad3 siRNA also resulted in a decrease in BIM protein, suggesting that TGFβ-1 + dasatinib-induced apoptosis is mediated by Smad3 regulation of BIM. Dasatinib is only effective in killing EGFR mutant cells, which is shown in only 10% of NSCLCs. Therefore, the observation that wild-type EGFR lung cancers can be manipulated to render them sensitive to killing by dasatinib could have important implications for devising innovative and potentially more efficacious treatment strategies for this disease.

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Related in: MedlinePlus

3D Docked Pose and Interactions of dasatinib and bosutinib with TβR-I 3D rendering of the binding pose of (A) dasatinib and (B) bosutinib docked into TβR-1.Protein is represented by purple carbon cartoon representation with residues surrounding a ligand are in line representation. Bosutinib is colored with magenta carbons and dasatinib with green carbons. Hydrogen bonds represented by dashed yellow lines with distances (gray) and interacting residue (black) labeled. A π-π stacking interaction between the phenyl of TYR-219 and the pyrimidine of dasatinib is circled in red.
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pone-0114131-g007: 3D Docked Pose and Interactions of dasatinib and bosutinib with TβR-I 3D rendering of the binding pose of (A) dasatinib and (B) bosutinib docked into TβR-1.Protein is represented by purple carbon cartoon representation with residues surrounding a ligand are in line representation. Bosutinib is colored with magenta carbons and dasatinib with green carbons. Hydrogen bonds represented by dashed yellow lines with distances (gray) and interacting residue (black) labeled. A π-π stacking interaction between the phenyl of TYR-219 and the pyrimidine of dasatinib is circled in red.

Mentions: Based on our docking studies we hypothesize that, dasatinib is a stronger binder to TβR-I when docked into the site characterized by the dorsomorphin co-crystallized with the kinase domain of TβR-I. This pocket, according to our modeling, is a likely binding site for the four ligands computationally probed against TβR-I. Our hypothesis, supported by the previous results of ligand affinity chromatography, and stronger binding of dasatinib versus bosutinib, is in agreement with the binding experiments. Based on the structural analysis of the docking results, stronger binding of dasatinib relative to bosutinib may largely contribute to an extra π-π stacking interaction between the phenyl of TYR-219 and pyrimidine of dasatinib. The 3D pose view of dasatinib and bosutinib is presented in Figs. 7A and 7B respectively. Although docking of bosutinib reveals an extra hydrogen-bond, overall the intra-molecular hydrogen bonds formed in the complex are farther apart and some with less favorable geometry which diminishes their contribution to binding when compared to hydrogen bonding between dasatinib and TβR-I.


Transforming growth factor β signaling overcomes dasatinib resistance in lung cancer.

Gordian E, Li J, Pevzner Y, Mediavilla-Varela M, Luddy K, Ohaegbulam K, Daniel KG, Haura EB, Muñoz-Antonia T - PLoS ONE (2014)

3D Docked Pose and Interactions of dasatinib and bosutinib with TβR-I 3D rendering of the binding pose of (A) dasatinib and (B) bosutinib docked into TβR-1.Protein is represented by purple carbon cartoon representation with residues surrounding a ligand are in line representation. Bosutinib is colored with magenta carbons and dasatinib with green carbons. Hydrogen bonds represented by dashed yellow lines with distances (gray) and interacting residue (black) labeled. A π-π stacking interaction between the phenyl of TYR-219 and the pyrimidine of dasatinib is circled in red.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4263601&req=5

pone-0114131-g007: 3D Docked Pose and Interactions of dasatinib and bosutinib with TβR-I 3D rendering of the binding pose of (A) dasatinib and (B) bosutinib docked into TβR-1.Protein is represented by purple carbon cartoon representation with residues surrounding a ligand are in line representation. Bosutinib is colored with magenta carbons and dasatinib with green carbons. Hydrogen bonds represented by dashed yellow lines with distances (gray) and interacting residue (black) labeled. A π-π stacking interaction between the phenyl of TYR-219 and the pyrimidine of dasatinib is circled in red.
Mentions: Based on our docking studies we hypothesize that, dasatinib is a stronger binder to TβR-I when docked into the site characterized by the dorsomorphin co-crystallized with the kinase domain of TβR-I. This pocket, according to our modeling, is a likely binding site for the four ligands computationally probed against TβR-I. Our hypothesis, supported by the previous results of ligand affinity chromatography, and stronger binding of dasatinib versus bosutinib, is in agreement with the binding experiments. Based on the structural analysis of the docking results, stronger binding of dasatinib relative to bosutinib may largely contribute to an extra π-π stacking interaction between the phenyl of TYR-219 and pyrimidine of dasatinib. The 3D pose view of dasatinib and bosutinib is presented in Figs. 7A and 7B respectively. Although docking of bosutinib reveals an extra hydrogen-bond, overall the intra-molecular hydrogen bonds formed in the complex are farther apart and some with less favorable geometry which diminishes their contribution to binding when compared to hydrogen bonding between dasatinib and TβR-I.

Bottom Line: As a result, TKIs often developed for a specific purpose have been found to act on other targets.We found that dasatinib treatment alone had very little effect; however, when NSCLC cell lines were treated with a combination of TGFβ and dasatinib, apoptosis was induced.Knockdown of the expression of Smad3 using Smad3 siRNA also resulted in a decrease in BIM protein, suggesting that TGFβ-1 + dasatinib-induced apoptosis is mediated by Smad3 regulation of BIM.

View Article: PubMed Central - PubMed

Affiliation: Molecular Oncology Program, H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida 33612, United States of America.

ABSTRACT
Lung cancer is the second most common cancer and the leading cause of cancer-related deaths. Despite recent advances in the development of targeted therapies, patients with advanced disease remain incurable, mostly because metastatic non-small cell lung carcinomas (NSCLC) eventually become resistant to tyrosine kinase inhibitors (TKIs). Kinase inhibitors have the potential for target promiscuity because the kinase super family is the largest family of druggable genes that binds to a common substrate (ATP). As a result, TKIs often developed for a specific purpose have been found to act on other targets. Drug affinity chromatography has been used to show that dasatinib interacts with the TGFβ type I receptor (TβR-I), a serine-threonine kinase. To determine the potential biological relevance of this association, we studied the combined effects of dasatinib and TGFβ on lung cancer cell lines. We found that dasatinib treatment alone had very little effect; however, when NSCLC cell lines were treated with a combination of TGFβ and dasatinib, apoptosis was induced. Combined TGFβ-1 + dasatinib treatment had no effect on the activity of Smad2 or other non-canonical TGFβ intracellular mediators. Interestingly, combined TGFβ and dasatinib treatment resulted in a transient increase in p-Smad3 (seen after 3 hours). In addition, when NSCLC cells were treated with this combination, the pro-apoptotic protein BIM was up-regulated. Knockdown of the expression of Smad3 using Smad3 siRNA also resulted in a decrease in BIM protein, suggesting that TGFβ-1 + dasatinib-induced apoptosis is mediated by Smad3 regulation of BIM. Dasatinib is only effective in killing EGFR mutant cells, which is shown in only 10% of NSCLCs. Therefore, the observation that wild-type EGFR lung cancers can be manipulated to render them sensitive to killing by dasatinib could have important implications for devising innovative and potentially more efficacious treatment strategies for this disease.

Show MeSH
Related in: MedlinePlus