CUT&RUN-sequencing identifies PTK7 as a direct Wnt target in patient-derived colorectal cancer organoids

The aberrant activation of Wnt/β-catenin signaling by APC mutations is a hallmark of colorectal cancer (CRC), but targeting Wnt signaling therapeutically has proven challenging. Deciphering the molecular effects of mutant APC-driven Wnt activation is crucial to enable the discovery of novel therapeutic targets. Here, we employ CUT&RUN-sequencing in patient-derived CRC organoids derived from two donors to dissect the transcriptional regulation by β-catenin in CRC. This analysis identified several genes of interest for CRC development as potential β-catenin target genes. Among these, we characterize PTK7, a co-receptor of the Wnt pathway and stem cell marker, as a main transcriptional target of β-catenin in CRC. We confirm that the expression of PTK7 is directly regulated by β-catenin in a comprehensive panel of CRC models. We demonstrate that APC mutations introduced by CRISPR/Cas9 result in the upregulation of PTK7 expression in human colon organoids, underlining the relevance of this upregulation during CRC carcinogenesis. Finally, we show that PTK7 promotes proliferation in CRC models without definitively affecting canonical Wnt signaling. Together, these results suggest that PTK7, which can be potentially targeted by existing drugs, is a Wnt target gene that contributes to oncogenic growth in CRC.

• Type: Other
• Archiver: European Genome-phenome Archive (EGA)