Biochemical and Biophysical Research Communications, Vol.519, No.4, 838-845, 2019
DHPS-dependent hypusination of eIF5A1/2 is necessary for TGF beta/fibronectin-induced breast cancer metastasis and associates with prognostically unfavorable genomic alterations in TP53
Metastasis is the leading cause of mortality in patients with solid tumors. In this regard, we previously reported that Pseudopodium-Enriched Atypical Kinase One (PEAK1) is necessary for non-canonical Transforming Growth Factor beta (TGF beta) signaling and TGF beta/fibronectin-induced metastasis. Here, we demonstrate that inhibition of DHPS-dependent eIF5A1/2 hypusination blocks PEAK1 and E-Cadherin expression, breast cancer cell viability and TGF beta/fibronectin-induced PEAK1-dependent breast cancer metastasis. Interestingly, TGF beta stimulation of high-grade metastatic breast cancer cells increases and sustains eIF5A1/2 hypusination. We used a suite of bioinformatics platforms to search biochemical/functional interactions and clinical databases for additional control points in eIF5A1/2 and PEAK1-Epithelial to Mesenchymal Transition (EPE) pathways. This effort revealed that interacting EPE genes were enriched for TP53 transcriptional targets and were commonly co-amplified in breast cancer patients harboring inactivating TP53 mutations. Taken together, these results suggest that combinatorial therapies targeting DHPS and protein activities elevated in TP53-mutant breast cancers may reduce systemic tumor burden and improve patient outcomes. (C) 2019 Elsevier Inc. All rights reserved.