Thirdly, given that the localization of SPARC protein within NSCLC tissues is associated with disease prognosis, further studies on a larger cohort with different histologies are needed to establish all factors that regulate a heterogeneous and differential SPARC expression in NSCLC, and whether SPARC serves different functions in tumor and in the stroma. The gene discussed is SPARC; the disease is non-small cell lung carcinoma.