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Quantitative phosphoproteomics revealed interplay between Syk and Lyn in the resistance to nilotinib in chronic
Romain Gioia1, Cédric Leroy, Claire Drullion
1Hématopoïèse Leucémique et Cible Thérapeutique, Inserm U1035, Université Victor Ségalen, Bordeaux, France.
Abstract:
In this study, we have addressed how Lyn kinase signaling mediates nilotinib-resistance by quantitative phospho-proteomics using Stable Isotope Labeling with Amino acid in Cell culture. We have found an increased tyrosine phosphorylation of 2 additional tyrosine kinases in nilotinib-resistant cells: the spleen tyrosine kinase Syk and the UFO family receptor tyrosine kinase Axl. This increased tyrosine phosphorylation involved an interaction of these tyrosine kinases with Lyn. Inhibition of Syk by the inhibitors R406 or BAY 61-3606 or by RNA interference restored the capacity of nilotinib to inhibit cell proliferation. Conversely, coexpression of Lyn and Syk were required to fully induce resistance to nilotinib in drug-sensitive cells. Surprisingly, the knockdown of Syk also strongly decreased tyrosine phosphorylation of Lyn and Axl, thus uncovering interplay between Syk and Lyn. We have shown the involvement of the adaptor protein CDCP-1 in resistance to nilotinib. Interestingly, the expression of Axl and CDCP1 were found increased both in a nilotinib-resistant cell line and in nilotinib-resistant CML patients. We conclude that an oncogenic signaling mediated by Lyn and Syk can bypass the need of Bcr-Abl in CML cells. Thus, targeting these kinases may be of therapeutic value to override imatinib or nilotinib resistance in CML.
Insights
Lyn and Syk kinase signaling drives nilotinib resistance in chronic myeloid leukemia (CML) by bypassing Bcr-Abl. Targeting these kinases may overcome resistance to imatinib and nilotinib therapies.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Nilotinib is a tyrosine kinase inhibitor used to treat chronic myeloid leukemia (CML).
- Acquired resistance to nilotinib remains a significant clinical challenge in CML treatment.
- Understanding the molecular mechanisms of resistance is crucial for developing effective therapeutic strategies.
Purpose of the Study:
- To investigate the role of Lyn kinase signaling in mediating nilotinib resistance in CML.
- To identify novel molecular targets for overcoming nilotinib resistance.
Main Methods:
- Quantitative phosphoproteomics using Stable Isotope Labeling with Amino acid in Cell culture (SILAC).
- Inhibition of specific tyrosine kinases (Syk) using small molecule inhibitors (R406, BAY 61-3606) and RNA interference.
- Analysis of protein-protein interactions and expression levels.
Main Results:
- Increased tyrosine phosphorylation of spleen tyrosine kinase (Syk) and UFO family receptor tyrosine kinase Axl was observed in nilotinib-resistant cells, mediated by Lyn kinase.
- Inhibition of Syk restored nilotinib sensitivity by inhibiting cell proliferation.
- Coexpression of Lyn and Syk induced nilotinib resistance in drug-sensitive cells.
- Syk knockdown reduced Lyn and Axl phosphorylation, revealing a Syk-Lyn interplay.
- Increased expression of Axl and CDCP1 was found in resistant cell lines and CML patients.
Conclusions:
- Lyn and Syk kinase signaling can drive oncogenic signaling, bypassing Bcr-Abl dependency in CML.
- Targeting Lyn and Syk kinases presents a potential therapeutic strategy to overcome imatinib or nilotinib resistance in CML.
- The adaptor protein CDCP1 is implicated in nilotinib resistance.
