SIGLEC15 and neoplasm: Correlation analysis using TCGA dataset also confirmed that CAMSAP1 was positively correlated with CD274 (r = 0.341, p < 0.001), CTLA4 (r = 0.15, p = 0.004), HAVCR2 (r = 0.27, p < 0.001), PDCD1 (r = 0.177, p = 0.001), PDCD1LG2 (r = 0.158, p = 0.002), SIGLEC15 (r = 0.117, p = 0.024), TIGIT (r = 0.165, p = 0.001), especially CD274 (r > 0.3, p < 0.001), whereas LAG3 was not correlated with CAMSAP1. Previous studies have indicated that CAFs in the stroma regulate different tumor infiltrating immune cells and participate in immunosuppression.