Phosphoinositide 3-kinase/Akt signaling is essential for prostaglandin E2-induced osteogenic differentiation of rat tendon stem cells

► PI3-kinase/Akt signaling not ERK signaling, is involved in PGE2-induced osteogenic differentiation of rat tendon stem cells. ► Akt activation is involved in PGE2-induced BMP-2 production. ► PI3-kinase/Akt signaling is essential in BMP-2-induced osteogenic differentiation. ► PI3-kinase or Akt inhibitor does not inhibit BMP-2-activated Smad phosphorylation.