SMAD3 and neoplasm: Our group reported that serum activin A levels are significantly elevated in Stage IV PDAC patients than in healthy individuals.[11] Higher activin A levels are associated with metastasis and poor survival in PDAC patients and animals.[12] Correspondingly, high tumor SMAD3 expression is associated with tumor size, lymph node metastasis, and poor survival in PDAC patients.[13] However, it is unclear whether activin A suppression would hold therapeutic potentials for PDAC due perhaps to a limited understanding of target cells and/or mechanisms which activin A acts through to promote PDAC.