Figure 7.

CR1 is essential for CSC migration and growth at metastatic sites. (a) Flow cytometry analysis of CR1 and CD44v6 in colon CSC line Pt1 (b) Percentage of migrated CSC in samples transduced with the TRIPZ sh4890 vector in the absence of doxycycline (Non-induced) or in the presence of doxycycline, which activates CR1 silencing mediated by the sh4890 RNA (shCR1) (c) Formation of lung tumors by colon cancer spheroids (line Pt1) transduced with TRIPZ sh4890 in the absence or in the presence of doxycycline (Non-induced and shCR1, respectively), detected 4 months following caudal vein injection. Left: representative picture of mice 4 months after injection; right: quantification of lung tumors derived from three different experiments. ***P<0.001 (d) Mice (eight) were inoculated in the spleen with CSCs transduced as above and left without doxycycline (Non-induced) to allow the growth of splenic xenografts (left panel). After 1 month, the spleen was removed and mice were divided into two groups, one of which was left untreated (Non-induced) while the other received doxycycline in the drinking water to activate CR1 silencing (shCR1 after splenectomy). Mice were monitored for the growth of liver metastases (central panels), which were quantified by bioimaging (right graph). **P<0.01