title: PTX1(ERGIC2)-VP22 fusion protein upregulates interferon-beta in prostate cancer cell line PC-3.
abstract: PTX1 is a gene identified by subtractive hybridization on the basis that it is expressed in normal prostate and not in prostate carcinoma. It is unrelated to the pituitary homeobox protein (Ptx1 or Pitx1), which regulates pituitary hormone gene expression, and its function is currently unknown. Recently, it was found to be a homolog of the yeast Erv41p, an endoplasmic reticulum (ER) resident protein involved in protein trafficking between ER and Golgi, and was renamed as ERGIC2. Ectopic expression of a partial sequence of PTX1 (Met84 - Leu225) as a VP22-fusion protein in prostate cancer cell line, PC-3, induced cellular senescence. Gene expression microarray analyses showed that interferon-beta (IFN-beta) and a number of IFN-inducible genes, among other genes, were upregulated by the PTX1-VP22 fusion protein. Upregulation of IFN-beta was confirmed by RTPCR and promoter-reporter assay. However, the upregulation of IFN-beta by the PTX1-VP22 fusion protein was not due to nuclear translocation of the PTX1 luminal domain.
authors.affiliation: Department of Pathology and Laboratory Medicine, Albert Einstein Medical Center, Philadelphia, Pennsylvania 19141-3098, USA. kwoks@einstein.edu
authors.forename: Simon C M
authors.initials: SC
authors.lastname: Kwok
authors.forename: Xianhong
authors.initials: X
authors.lastname: Liu
authors.forename: Patricia
authors.initials: P
authors.lastname: Mangel
authors.forename: Ierachmiel
authors.initials: I
authors.lastname: Daskal
mesh_terms: D045744:Cell Line, Tumor; D016922:Cellular Senescence; D004721:Endoplasmic Reticulum / Q000378:metabolism; D020869:Gene Expression Profiling; D006801:Humans; D016899:Interferon-beta / Q000235:genetics*; D008297:Male; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D015854:Up-Regulation; D033921:Vesicular Transport Proteins
chemical_list: C431845:ERGIC2 protein, human; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D033921:Vesicular Transport Proteins; D016899:Interferon-beta