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bioRxiv · 10.1101/229658

DARPP-32 and t-DARPP promote lung cancer growth through IKKα-dependent cell migration and Akt/Erk-mediated cell survival

Abstract

Lung cancer is the leading cause of cancer-related death worldwide. In this study, we demonstrate that elevated expression of dopamine and cyclic adenosine monophosphate-regulated phosphoprotein, Mr 32000 (DARPP-32) and its truncated splice variant t-DARPP promotes lung tumor growth, while abrogation of DARPP-32 expression in human non-small cell lung cancer (NSCLC) cells reduces tumor growth in orthotopic mouse models. We observe a novel physical interaction between DARPP-32 and inhibitory kappa B kinase- (IKK) that promotes NSCLC cell migration through non-canonical nuclear factor kappa-light-chain-enhancer of activated B cells 2 (NF-{kappa}B2) signaling. Bioinformatics analysis of 513 lung adenocarcinoma patients reveals elevated t-DARPP isoform expression is associated with poor overall survival. Histopathological investigation of 62 human lung adenocarcinoma tissues also showed that t-DARPP expression is elevated with increasing tumor (T) stage. Our data suggest that DARPP-32 is a negative prognostic marker associated with increasing stages of NSCLC and may represent a novel therapeutic target.

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BibTeXRIS

Alam, S. K., Astone, M., Liu, P., Hall, S. R., Coyle, A. M., Dankert, E. N., Hoffman, D. K., Zhang, W., Kuang, R., Roden, A. C., Mansfield, A. S., Hoeppner, L. H.. 2017-12-06. DARPP-32 and t-DARPP promote lung cancer growth through IKKα-dependent cell migration and Akt/Erk-mediated cell survival. https://doi.org/10.1101/229658

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