Loss of desmocollin-2 confers a tumorigenic phenotype to colonic epithelial cells through activation of Akt/β-catenin signaling

• Published in: Molecular biology of the cell 2011-04, Vol.22 (8), p.1121-1134
• Main Authors: Kolegraff, Keli, Nava, Porfirio, Helms, My N, Parkos, Charles A, Nusrat, Asma
• Format: Article
• Language: English
• Subjects: Animals; beta Catenin - genetics; beta Catenin - metabolism; Caco-2 Cells; Cell Proliferation; Colon - metabolism; Colon - pathology; Colonic Neoplasms - genetics; Colonic Neoplasms - metabolism; Colonic Neoplasms - pathology; Colorectal Neoplasms - genetics; Colorectal Neoplasms - metabolism; Colorectal Neoplasms - pathology; Desmocollins - deficiency; Desmocollins - genetics; Desmoglein 2 - genetics; Desmoglein 2 - metabolism; Desmosomes - genetics; Desmosomes - metabolism; Desmosomes - pathology; Gene Expression Regulation, Neoplastic; Gene Silencing; Humans; Mice; Mice, Knockout; Oncogene Protein v-akt - antagonists & inhibitors; Oncogene Protein v-akt - genetics; Oncogene Protein v-akt - metabolism; Phenotype; Protein Kinase Inhibitors - pharmacology; RNA, Small Interfering - metabolism; Signal Transduction - drug effects; Signal Transduction - genetics; Transcription, Genetic; Transfection
• ISSN: 1059-1524; 1939-4586
• DOI: 10.1091/mbc.E10-10-0845

Desmocollin-2 (Dsc2) and desmoglein-2 (Dsg2) are transmembrane cell adhesion proteins of desmosomes. Reduced expression of Dsc2 has been reported in colorectal carcinomas, suggesting that Dsc2 may play a role in the development and/or progression of colorectal cancer. However, no studies have examined the mechanistic contribution of Dsc2 deficiency to tumorigenesis. Here we report that loss of Dsc2 promotes cell proliferation and enables tumor growth in vivo through the activation of Akt/β-catenin signaling. Inhibition of Akt prevented the increase in β-catenin-dependent transcription and proliferation following Dsc2 knockdown and attenuated the in vivo growth of Dsc2-deficient cells. Taken together, our results provide evidence that loss of Dsc2 contributes to the growth of colorectal cancer cells and highlight a novel mechanism by which the desmosomal cadherins regulate β-catenin signaling.