Casein kinase I isoform alpha, also known as CKI-alpha, CK1 and CSNK1A1, is a cytoplasm protein which belongs to the protein kinase superfamily, CK1 Ser/Thr protein kinase family and casein kinase I subfamily. Casein kinases are operationally defined by their preferential utilization of acidic proteins such as caseins as substrates. High expression of CSNK2A1, or concomitantly high expression of CSNK2A1, are independent prognostic factors of poor survival in NSCLC patients. CSNK2A1 are useful prognosis markers in non-small cell lung cancer (NSCLC) patients after complete resection, independent of lymph node metastasis status. CSNK1A1 can phosphorylate a large number of proteins. It participates in Wnt signaling. It phosphorylates CTNNB1 at 'Ser-45'. CSNK1A1 may play a role in segregating chromosomes during mitosis.