RNA-seq study of a helicon peptide targeting ß-Catenin/TCF transcription factor [shRNA]

Constitutive activation of Wnt/ß-catenin signaling drives tumor initiation, maintenance, and metastasis in numerous preclinical models. Within the nucleus, ß-catenin interacts with transcription factors of the TCF/LEF (T cell factor/lymphoid enhancer factor, TCFs) family. The transcriptional program mediated by these ß-catenin/TCF interactions promotes cell proliferation, epithelial-mesenchymal transition (EMT), and a cancer stem-cell phenotype. COLO320DM is a human colorectal cancer line with an activated Wnt/ ß-catenin pathway driven by an APC mutation. Here, we apply a doxycycline-inducible shRNA to knockdown (KD) CTNNB1 (encoding ß-catenin) and study the impact on the global transcriptome of COLO320DM. We also design and express an shRNA-resistant rescue cDNA to rule out any potential off-target effect. The results reveal a global gene expression change upon CTNNB1-KD that is consistent with ß-catenin's role in serving as a signal hub downstream of the canonical Wnt pathway. Overall design: COLO320DM xenograft tumor models were prepared by WuXi AppTec (HongKong). Mice were randomized and a doxycycline-containing diet was introduced when the average tumor size reaches 150mm3. Tumor samples were collected on day 3 post dox treatment and flash-frozen until RNA extraction