Regulation of Protein Translation and c-jun expression by Prostate Tumor Overexpressed1 (PTOV1) Verónica Cánovas, PhD Student Laboratory of Cell Signalling and Cancer Progression, Dra. Rosanna Paciucci Research Unit in Biomedicine and Translational Oncology Vall d Hebron Institute of Research (Barcelona, Spain) Regulation of protein translation and c-jun expression by Prostate Tumor Overexpressed 1 (PTOV1) N. Marqués, M. Sesé, V. Cánovas, F. Valente, R. Bermudo, I. de Torres, Y. Fernández, I. Abasolo, P. L Fernández, H. Contreras, E. Castellón, T. Celià-Terrassa, R.l Méndez, S. Ramón y Cajal, T. M. Thomson and R. Paciucci Oncogene. 2013 Mar 4. doi: 10.1038/onc.2013.51.
PTOV1: a novel protein overexpressed in prostate cancer Benign Peripheral Zone High Grade Prostate Intraepithelial Neoplasia Carcinoma 3.4% 80% 71% A and B have 80% homology PTOV1 A B 151aa 147aa 416 aa Benedit et al., Oncogene, 2001 F. Bontems et al., J Struct Biol 2011 PTOV1 is overexpressed in prostate cancers and pre-neoplastic lesions, but it is not detected, or expressed at low levels, in the normal associated tissue (BPZ)
PTOV1 expression in High-Grade PIN predicts prostate cancer in needle biopsy HG-PIN Prostate cancer CTL + PTOV1 is a useful marker for the early diagnosis of prostate cancer Normal prostate CTL - Biopsies with cancer Biopsies without cancer Relationship between PTOV1expression in HG-PIN lesions and the presence of prostate cancer. Morote J. et al., Clin Cancer Res. 2008.
Prostate cancer PTOV1 induces cell proliferation PTOV1 Ki67 High levels of PTOV1 in tumors and in cells lines correlate significantly with a higher proliferative index Santamaría et al., Am J Pathol 2003
PTOV1 is overexpressed in several tumor types, significantly associated to malignancy and to proliferation kidney pancreas glioblastoma bladder colon The overexpression of PTOV1 is significantly associated to tumors with high grade Fernández S. et al., Virchows Arch. 2011
These evidences suggest a pro-oncogenic function of PTOV1 in prostate cancer. To prevent PTOV1 action in cancer we need to know its function and mechanisms of action.
PTOV1 interacts with RACK1, the Receptor of Activated protein C Kinase PTOV1 interacts directly with RACK1, a regulator of PKC and Jun signaling and a component of the 40S ribosome
PTOV1 associates with the 40S ribosome and regulates protein synthesis up Sucrose gradient down The association of PTOV1 with RACK1 and ribosomes influences protein translation in a mtorc1 dependent manner
PTOV1 enhances translation of the c-jun mrna Protein levels mrna levels PTOV1 stimulates c-jun expression by promoting its translation without affecting its mrna levels
PTOV1 promotes c-jun-dependent enhanced motility and invasion in cancer cells Invasion assay High levels of PTOV1 result in increased levels of active c-jun that promotes SNAI1 transcription, ultimately engaging a mesenchymal-like gene program and enhanced cell invasion qpcr Western Blot Chromatin IP
PTOV1 promotes tumorigenesis and metastasis of PC-3 prostate cancer cells PC3 shctl PC3 shptov1 Knockdown of PTOV1 significantly inhibits tumor growth and causes a delay in the metastatic spread of tumor cells.
Concordant expression of high levels of PTOV1 and active c-jun in association with prostate cancer progression. Normal prostate Staining for both PTOV1 and phosphorylated c-jun showed a significant concordance in prostate tumors Metastasis PTOV1 PTOV p-cjun
Conclusions Collectively, our observations suggest that, in the course of malignant progression, prostate tumors express abnormally high levels of PTOV1 to upregulate c-jun translation and activity as a mechanism to enable and promote a full-blown metastatic phenotype.
Lide Alaña Neus Marqués Rosanna Paciucci Verónica Cánovas Acknowledgements Marta Sesé Pedro J. Guijarro Yolanda Puñal Inés de Torres and S. Ramón y Cajal (Department of Pathology, Vall d Hebron Hospital) Yolanda Fernández ( Molecular Imaging Platform CIBBIM-Nanomedicine, Vall d Hebron Institut de Recerca Héctor Contreras ( Laboratory of molecular and cellular andrology,physiology and biophysic, University of Chile) Toni Celià-Terrassa and Timothy M. Thomson ( Department of Cell Biology, CSIC, Barcelona) Raúl Mendez ( Institute for Research in Biomedicin, Parc Cientific, Barcelona Laboratory of Cell Signalling and Cancer Progression, Dra Rosanna Paciucci Research Unit in Biomedicine and Translational Oncology, Vall d Hebron Institut of Research
Yeast two hybrid interactions RACK1 Flotillin-1 PSMB4 BAT4 KIAA0804 eif3ε Receptor for activated PKCIGF-1R/ IR singaling, cell proliferation/ motility Intracellular vesicular transit, IGF-1R/IR receptor signaling Subunit 4b of human proteasome Subunit 4 of HLA-associated transcript 4, G-patch domain RNA binding RING finger domain protein ( E3 ubiquitin ligase Subunit of the traslation initiation factor eif3 Interactions of PTOV1 found by other groups CBP 14-3-3σ Domain BUZ/Znf- UBP Histon acetyl transferase, transcription activation Binding of phosphorilated proteins in the cytoplasm Present in HDAC6, its a E3 ubiquitin binding