The present invention provides a method for treating a subject having a clinical condition associated with increased level of L1 expression. The method generally includes determining the expression level of L1 in a subject and administering a TGF-1 inhibitor to a subject having an increased level of L1 expression. The clinical conditions that can be treated using the method of the invention include, but are not limited to, cancer, chronic obstructive pulmonary disease (COPD), atherosclerosis and pulmonary vascular disease as well as other fibrotic and inflammatory diseases.
