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bioRxiv · 10.1101/466946

The pro-oncogenic adaptor CIN85 inhibits hypoxia-inducible factor prolyl hydroxylase-2

Abstract

The EGFR-adaptor protein CIN85 has been shown to promote breast cancer malignancy and hypoxia-inducible factor (HIF) stability. However, the mechanisms underlying cancer promotion remain ill-defined. Here, we show that CIN85 is a novel binding partner of the main HIF-prolyl hydroxylase PHD2, but not of PHD1 or PHD3. Mechanistically, the N-terminal SH3 domains of CIN85 interact with the proline-arginine rich region within the N-terminus of PHD2, thereby inhibiting PHD2 activity and HIF-degradation. This activity is essential in vivo, as specific loss of the CIN85-PHD2 interaction in CRISPR/Cas9 edited cells affected growth and migration properties as well as tumor growth in mice. Overall, we discovered a previously unrecognized tumor growth checkpoint that is regulated by CIN85-PHD2, and uncovered an essential survival function in tumor cells linking growth factor adaptors with hypoxia signaling.

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BibTeXRIS

Kozlova, N., Mennerich, D., Samoylenko, A., Dimova, E. Y., Koivunen, P., Biterova, E., Richter, K., Hassinen, A., Kellokumpu, S., Manninen, A., Miinalainen, I., Glumoff, V., Ruddock, L., Drobot, L., Kietzmann, T.. 2018-11-09. The pro-oncogenic adaptor CIN85 inhibits hypoxia-inducible factor prolyl hydroxylase-2. https://doi.org/10.1101/466946

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