CTTN and breast cancer: In contrast to primary breast cancers and head and neck squamous cell carcinoma cell lines, for which a correlation of cortactin gene amplification with overexpression at the mRNA level was reported [11, 23, 30], we were unable to detect a significant upregulation of cortactin at the mRNA level when comparing cortactin mRNA expression in fresh frozen samples from PDAC tumor tissue and non-neoplastic pancreatic tissue.