Moreover, results with human primary cancer xenografts in mice suggest an alternative to the widely accepted view that canonical WNT signaling is essential for advanced intestinal tumor growth and metastases: repression of WNT-TCF signaling with dnTCF4, the same tool used to show the in vitro WNT dependency of human colon cancer cells [18], is generally ineffective to decrease tumor burden in xenografts in mice. This evidence concerns the gene HNF4A and cancer.