Project description:Metastasis is the leading cause of cancer-related mortality. Cancer stem cells contribute to metastasis in the murine colon cancer models, but the underlying mechanisms are unclear. Here we report a Wnt ligand, Dickkopf2 (DKK2) is essential for colorectal cancer stemness. Genetic depletion of Dkk2 in intestinal epithelial or stem cells reduced tumorigenesis as well as expression of the stem cell marker gene Lgr5 in a model of colitis-associated cancer. Mechanistically, DKK2 activates c-Src followed by increased LGR5 expressing stem cells in colorectal cancer through degradation of HNF4α1. Splenic injection of DKK2-deficient cancer organoids into C57BL/6 mice resulted in a significant reduction of liver metastases compared to the control cancer organoids in spite of the presence of oncogenic mutations in Apc, Kras and Tp53 genes. These findings suggest that DKK2 is required for stemness of colorectal cancer cells, which in turn contributes to metastasis.
Project description:Metastasis is the leading cause of cancer-related mortality. Cancer stem cells contribute to metastasis in the murine colon cancer models, but the underlying mechanisms are unclear. Here we report a Wnt ligand, Dickkopf2 (DKK2) is essential for colorectal cancer stemness. Genetic depletion of Dkk2 in intestinal epithelial or stem cells reduced tumorigenesis as well as expression of the stem cell marker gene Lgr5 in a model of colitis-associated cancer. Mechanistically, DKK2 activates c-Src followed by increased LGR5 expressing stem cells in colorectal cancer through degradation of HNF4α1. Splenic injection of DKK2-deficient cancer organoids into C57BL/6 mice resulted in a significant reduction of liver metastases compared to the control cancer organoids in spite of the presence of oncogenic mutations in Apc, Kras and Tp53 genes. These findings suggest that DKK2 is required for stemness of colorectal cancer cells, which in turn contributes to metastasis.
Project description:Metastasis is the leading cause of cancer-related mortality. Cancer stem cells contribute to metastasis in the murine colon cancer models, but the underlying mechanisms are unclear. Here we report a Wnt ligand, Dickkopf2 (DKK2) is essential for colorectal cancer stemness. Genetic depletion of Dkk2 in intestinal epithelial or stem cells reduced tumorigenesis as well as expression of the stem cell marker gene Lgr5 in a model of colitis-associated cancer. Mechanistically, DKK2 activates c-Src followed by increased LGR5 expressing stem cells in colorectal cancer through degradation of HNF4α1. Splenic injection of DKK2-deficient cancer organoids into C57BL/6 mice resulted in a significant reduction of liver metastases compared to the control cancer organoids in spite of the presence of oncogenic mutations in Apc, Kras and Tp53 genes. These findings suggest that DKK2 is required for stemness of colorectal cancer cells, which in turn contributes to metastasis.
Project description:To validate how FIBP influences stemness, we obtained the genome-wide methylation in HCT116-CSCs by an Illumina HumanMethylation450 BeadChip.
Project description:Here, using mouse squamous cell carcinoma cells, we report a completely new function for the autophagy protein Ambra1 as the first described ‘spatial rheostat’ controlling the Src/FAK pathway. Ambra1 regulates the targeting of active phospho-Src away from focal adhesions into autophagic structures that cancer cells use to survive adhesion stress. Ambra1 binds to both FAK and Src in cancer cells. When FAK is present, Ambra1 is recruited to focal adhesions, promoting FAK-regulated cancer cell direction-sensing and invasion. However, when Ambra1 cannot bind to FAK, abnormally high levels of phospho-Src and phospho-FAK accumulate at focal adhesions, positively regulating adhesion and invasive migration. Spatial control of active Src requires the trafficking proteins Dynactin 1 and IFITM3, which we identified as Ambra1 binding partners by interaction proteomics. We conclude that Ambra1 is a core component of an intracellular trafficking network linked to tight spatial control of active Src and FAK levels, and so crucially regulates their cancer-associated biological outputs.