COPB2 and malignant colon neoplasm: Moreover, COPB2 can induce G0/G1 and G2/S phase arrest in various types of cancers [1,3,4]; the regulatory action of COPB2 on the contributors of cell-cycle progressions, such as cyclin A, p21, and p16, was indicated as the underlying molecular mechanism of cell-cycle arrest in human colon cancer [1].