HOXA5 counteracts stem cell traits by inhibiting Wnt signaling

Here we identify HOXA5 as an important repressor of intestinal stem cell fate in vivo and identify a reciprocal feedback between HOXA5 and Wnt signaling. HOXA5 is suppressed by the Wnt pathway to maintain stemness and becomes active only outside the intestinal crypt where it inhibits Wnt signaling to enforce differentiation. In colon cancer, HOXA5 is down-regulated and its re-expression induces loss of the cancer stem cell phenotype preventing tumor progression and metastasis. Tumor regression by HOXA5 induction can be triggered by retinoids, which represents a tangible means to treat colon cancer by eliminating cancer stem cells. We use microarrays to identify HOXA5 signature in SW480 human colon carcinoma cell line RNA was obtained from SW480 cells, transduced with HOXA5 OE or HOXA5 KD. Hybridization was performed on Affymetrix microarrays.