PDGF as a biomarker for predicting resistance or effect of c-Met targeting drugs

A method for evaluating efficacy of a c-Met targeting agent in a patient with lung cancer, the method comprising:

• measuring PDGF protein level in a test sample comprising lung cancer cells obtained from a patient with lung cancer and in a reference sample comprising lung cancer cells resistant to the c-Met targeting agent,
• comparing the PDGF protein level of the test sample and the reference sample,
• evaluating whether the c-Met targeting agent is effective in treating the lung cancer based on a change in PDGF protein level, wherein a lower PDGF protein level in the test sample compared to the PDGF protein level in the reference sample indicates that the c-Met targeting agent is efficacious in treating the lung cancer, and
• administering the c-Met targeting agent to the patient if the c-Met targeting agent is indicated to be effective in treating the lung cancer,
• wherein the c-Met targeting agent comprises an anti-c-Met antibody or an antigen-binding fragment thereof.