The present invention relates to the constitutive activity of the Hedgehog pathway in non-small cell lung carcinoma (NSCLC). A method for diagnosing NSCLC by detecting the level of a component of the Hedgehog pathway is provided, as is a method for identifying subjects that will respond positively to treatment with a Hedgehog pathway antagonist. Methods for treating subjects with cancer or cancers resistant to Hedgehog pathway antagonists are also provided.
