Although several signaling pathways such as ARF/MDM2/p53, TNF-a and IGF have been reported to be associated with the anti-apoptotic effects of Twist in osteoblasts and fibroblasts [36]–[37], signalings involved in the Twist-associated anti-apoptotic role of lung cancer cells required further studies. The gene discussed is IGF1; the disease is lung carcinoma.