Arginylation is a post-translational modification wholly mediated by Arginyltransferase 1 (Ate1). Our studies have shown that Ate1 and arginylation are upregulated during stress conditions. In addition, it was recently shown that Ate1-deficient fibroblasts demonstrate cancer-like characteristics including genomic instability and mutagenesis. While Ate1’s role in cancer is poorly understood, our preliminary studies suggest that Ate1 is an important regulator of metastasis and cancer progression in prostate cancer models. In this study, our data suggests that Ate1 is essential for normal cell stress response in conditions including cellular oxidant, apoptosis inducing drugs, and radiation. Further, we show that a loss of Ate1 in LnCaP prostate cancer cells increases anchorage-independent growth in the soft-agar assay, and that a loss of Ate1 in PC-3 prostate cancer cells increases matrigel invasion in the Boyden chamber assay. To text how Ate1 affects metastasis in vivo, PC-3 cells with Ate1 or control shRNA were orthotopically implanted into the prostates of immunocompromised mice to observe metastasis. While very little metastasis was observed in PC-3 control cells, PC-3 cells with reduced Ate1 achieved much higher levels of metastasis. In conclusion, our data suggests that the loss of Ate1 in prostate cancer promotes cancer progression phenotypes and cell survival. In future studies, we will examine if Ate1 levels in human prostate cancers in prostate cancer prognosis.

Citation Format: Michael Birnbaum, Akhilesh Kumar, William Morgan, Fangliang Zhang. Arginyltransferase1 as a novel suppressor of prostate cancer metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3523. doi:10.1158/1538-7445.AM2017-3523