Rationale for co-targeting IGF-1R and ALK in ALK fusion-positive lung cancer

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Crizotinib, an anaplastic lymphoma receptor tyrosine kinase (ALK) inhibitor, is effective in ALK-fusion-positive lung cancer but faces challenges with response variability and acquired resistance.
• Clinical observation of a patient with exceptional response to an insulin-like growth factor 1 receptor (IGF-1R) antibody prompted investigation into combined therapies.

Purpose of the Study:

• To define a therapeutic synergism between ALK and IGF-1R inhibitors in lung cancer.
• To investigate the role of the IGF-1R-IRS-1 pathway in ALK tyrosine kinase inhibitor (TKI) sensitivity and resistance.

Main Methods:

• Investigated the interaction between ALK fusion proteins and insulin receptor substrate 1 (IRS-1).
• Assessed the impact of IRS-1 knockdown on ALK inhibitor efficacy.
• Evaluated combined ALK and IGF-1R inhibition in models of ALK TKI resistance.
• Analyzed biopsy samples from patients progressing on crizotinib.

Main Results:

• ALK fusion proteins bind to IRS-1, and IRS-1 knockdown enhances antitumor effects of ALK inhibitors.
• The IGF-1R pathway is activated in models of ALK TKI resistance, and combined inhibition improves efficacy.
• Increased levels of IGF-1R and IRS-1 were observed in patients progressing on crizotinib.

Conclusions:

• The IGF-1R-IRS-1 pathway plays a significant role in both ALK TKI-sensitive and resistant lung cancer states.
• Combined inhibition of ALK and IGF-1R presents a promising therapeutic strategy for lung cancer patients.
• These findings provide a rationale for the clinical development of dual ALK and IGF-1R inhibitors.