PP2A: Unveiling a Reluctant Tumor Suppressor

Although evidence has suggested that the serine/threonine protein phosphatase 2A (PP2A) might be a tumor suppressor protein, it has been difficult to pin down its role in tumor suppression because it acts in a wide variety of signaling pathways. Recent findings, including work in this issue by , provide convincing evidence that suppression of PP2A activity cooperates with other oncogenic changes to cause transformation of multiple cell types.