SMN1 and esophageal squamous cell carcinoma: Specifically, double positivity in ESCC stromal fibroblasts for Twist1 and PDGFRα (OS:P = 0.001 and DFS:P = 0.021), Twist1 and SMA (OS:P = 0.009 and DFS:P = 0.001), Twist1 and Tenascin-C (OS:P < 0.001 and DFS:P < 0.001) and Twist1 and FSP1 (OS:P < 0.001 and DFS:P = 0.001) were all very strongly correlated with reduced OS and DFS compared with controls with stromal fibroblasts that were negative for Twist1 and CAF markers (Figure 5).