GOLPH3 modulates mTOR signaling and rapamycin sensitivity in cancer

Genome-wide copy number analyses of human cancers identified a frequent 5p13 amplification in several solid tumour types, including lung (56%), ovarian (38%), breast (32%), prostate (37%) and melanoma (32%). Here, using integrative analysis of a genomic profile of the region, we identify a Golgi protein, GOLPH3, as a candidate targeted for amplification. Gain- and loss-of-function studies in vitro and in vivo validated GOLPH3 as a potent oncogene. Physically, GOLPH3 localizes to the trans-Golgi network and interacts with components of the retromer complex, which in yeast has been linked to target of rapamycin (TOR) signalling. Mechanistically, GOLPH3 regulates cell size, enhances growth-factor-induced mTOR (also known as FRAP1) signalling in human cancer cells, and alters the response to an mTOR inhibitor in vivo. Thus, genomic and genetic, biological, functional and biochemical data in yeast and humans establishes GOLPH3 as a new oncogene that is commonly targeted for amplification in human cancer, and is capable of modulating the response to rapamycin, a cancer drug in clinical use.

[1]  Y. Ikeda,et al.  Role of N-glycans in growth factor signaling , 2003, Glycoconjugate Journal.

[2]  T. Golub,et al.  Integrative genomic analyses identify MITF as a lineage survival oncogene amplified in malignant melanoma , 2005, Nature.

[3]  D. Elder,et al.  Melanoma cell lines from different stages of progression and their biological and molecular analyses , 1997, Melanoma research.

[4]  R. Abraham,et al.  Immunopharmacology of rapamycin. , 1996, Annual review of immunology.

[5]  J. Marth,et al.  Glycosylation in Cellular Mechanisms of Health and Disease , 2006, Cell.

[6]  V. Korolchuk,et al.  Drosophila Vps35 function is necessary for normal endocytic trafficking and actin cytoskeleton organisation , 2007, Journal of Cell Science.

[7]  L. Chin,et al.  Chromosomally unstable mouse tumours have genomic alterations similar to diverse human cancers , 2007, Nature.

[8]  C. Burd,et al.  Golgi localization of glycosyltransferases requires a Vps74p oligomer. , 2008, Developmental cell.

[9]  E. Hafen,et al.  Drosophila S6 kinase: a regulator of cell size. , 1999, Science.

[10]  L. Chin,et al.  High-resolution genomic profiles of human lung cancer. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[11]  S. Snyder,et al.  RAFT1 phosphorylation of the translational regulators p70 S6 kinase and 4E-BP1. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[12]  K. Howell,et al.  GMx33 associates with the trans-Golgi matrix in a dynamic manner and sorts within tubules exiting the Golgi. , 2005, Molecular biology of the cell.

[13]  D. Sabatini.  mTOR and cancer: insights into a complex relationship , 2006, Nature Reviews Cancer.

[14]  David M Sabatini,et al.  Defining the role of mTOR in cancer. , 2007, Cancer cell.

[15]  K. Guan,et al.  Expanding mTOR signaling , 2007, Cell Research.

[16]  Jyoti S. Choudhary,et al.  Proteomics Characterization of Abundant Golgi Membrane Proteins* , 2001, The Journal of Biological Chemistry.

[17]  Lewis C. Cantley,et al.  AKT/PKB Signaling: Navigating Downstream , 2007, Cell.

[18]  J. Blenis,et al.  Target of rapamycin (TOR): an integrator of nutrient and growth factor signals and coordinator of cell growth and cell cycle progression , 2004, Oncogene.

[19]  磯谷 周二.  Immunopurified mammalian target of rapamycin phosphorylates and activates p70 S6 kinase α in vitro , 2000 .

[20]  D. Rimm,et al.  Automated subcellular localization and quantification of protein expression in tissue microarrays , 2002, Nature Medicine.

[21]  Fulai Jin,et al.  Insights into TOR function and rapamycin response: chemical genomic profiling by using a high-density cell array method. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[22]  R. Hresko,et al.  mTOR·RICTOR Is the Ser473 Kinase for Akt/Protein Kinase B in 3T3-L1 Adipocytes* , 2005, Journal of Biological Chemistry.

[23]  T. P. Neufeld,et al.  Regulation of cellular growth by the Drosophila target of rapamycin dTOR. , 2000, Genes & development.

[24]  S. Eaton.  Retromer retrieves wntless. , 2008, Developmental cell.

[25]  Stefano Fumagalli,et al.  Disruption of the p70s6k/p85s6k gene reveals a small mouse phenotype and a new functional S6 kinase , 1998, The EMBO journal.

[26]  J. B. Sajous,et al.  Ras signalling on the endoplasmic reticulum and the Golgi , 2002, Nature Cell Biology.

[27]  L. Tu,et al.  Signal-Mediated Dynamic Retention of Glycosyltransferases in the Golgi , 2008, Science.

[28]  E. Hafen,et al.  Genetic and biochemical characterization of dTOR, the Drosophila homolog of the target of rapamycin. , 2000, Genes & development.

[29]  M. Hall,et al.  TOR Signaling in Growth and Metabolism , 2006, Cell.

[30]  K. Howell,et al.  GMx33: A Novel Family of trans‐Golgi Proteins Identified by Proteomics , 2000, Traffic.

[31]  J. Blenis,et al.  Mammalian cell size is controlled by mTOR and its downstream targets S6K1 and 4EBP1/eIF4E. , 2002, Genes & development.

[32]  D. Guertin,et al.  Phosphorylation and Regulation of Akt/PKB by the Rictor-mTOR Complex , 2005, Science.