We studied the role of NF-κB/IKK-mediated signaling in the stimulation of growth potential of mesenchymal progenitor cells by alkaloid songorine in vitro. Specific NF-κB inhibitor oridonin abolished activation of proliferation and differentiation of progenitor cells. Aurothiomalate, a selective blocker of IKK-2, also suppressed mitotic activity of fibroblast precursors, but had no effect on the rate of the differentiation.