RUNX2 and osteoporosis: Interestingly, we found that knockout of TZAP may also increase the mRNA level of Runx2 (a transcription factor that regulates osteogenic differentiation in MSCs [51]) and Alp (a widely known osteoblastic marker that has been used to evaluate bone formation capacity in osteoporosis [52]), while overexpression of TZAP in P2 pMSCs also led to downregulation of Alp, Cebpa and PPARγ.