Conversely, other preclinical studies have shown that the correlation of Src expression and tumor response to Src inhibition in the treatment of other tumor types including thyroid cancer cell lines is less clear, and p-FAK may be more predictive of response in thyroid cancer (Schweppe, 2009; Klutchko, 1998; Kraker, 2000). Here, PTK2 is linked to thyroid gland carcinoma.