For instance, dysregulated PDFN1 expression has been reported to occur in a variety of cancers, including gastric cancer, lung cancer, and colorectal cancer (6, 17–19); increased expression of PFDN2 has been found in bladder cancer (7); and it has been reported that PFDN4 is highly expressed in breast cancer (20). Here, PFDN4 is linked to lung carcinoma.