Figure 2.

Frequency of focal adhesion kinase (FAK) overexpression at protein level in human solid cancers. A Pubmed search of studies evaluating FAK protein expression in human cancers by immunohistochemistry (IHC) was performed to determine the percentage of cancer samples with increased FAK protein expression. The following keywords were used in the search strategy: FAK [All Fields] AND (“neoplasms” [MeSH Terms] OR “neoplasms” [All Fields] OR “cancer” [All Fields]) AND (“immunohistochemistry” [MeSH Terms] OR “immunohistochemistry” [All Fields]). The results were limited to English language studies. Manual searches of reference articles from applicable studies were performed to identify articles that may have been missed by the computer-assisted search. Abstracts were excluded for cell lines, pre-invasive tumors, if insufficient data to evaluate the methodological quality, absence of tumor total FAK staining, absence of FAK quantification or proportion, absence of proportion of samples overexpressing FAK. Non-eligible trials included ecological studies, case reports, reviews, editorials, and animal trials. This work was conducted in accordance with the PRISMA guidelines (Figure A1). N = number of cancers analysed.