Differential expression patterns of capping protein, protein phosphatase 1, and casein kinase 1 may serve as diagnostic markers for malignant melanoma

Early and accurate diagnosis of malignant melanoma is critical for patient survival. However, currently used diagnostic markers are insufficiently specific, which limits their utility. We aimed to identify molecular markers that are more specific to malignant melanoma, thereby aiding in melanoma diagnosis and treatment. PCR-based suppression subtractive hybridization was used to identify capping protein Z-line α1 (CAPZA1), protein phosphatase 1 catalytic subunit β isoform (PP1CB), and casein kinase 1 α1 (CSNK1A1) as being differentially expressed between melanoma cells and normal melanocytes. qRT-PCR and Western blot analysis confirmed that these genes were over-expressed in melanoma cells. In addition, immunohistochemical assays revealed that expression of PP1CB and CSNK1A1 was significantly greater in human melanoma specimens than nevi (p<0.0001). Combined application of PP1CBand CSNK1A showed high sensitivity and specificity for melanoma. Thus, our data suggest PP1CB and CSNK1A1 are potential biomarkers for distinguishing malignant melanoma from other melanocytic lesions. In addition, because CAPZA1, PP1CB and CSNK1A1 are involved in cell motility, which underlies invasion and metastasis of human cancer, they may also be novel targets for anti-metastatic therapies.