@article{46bea940540a11de87b8000ea68e967b,
title = "Regulation of YKL-40 expression during genotoxic or microenvironmental stress in human glioblastoma cells",
abstract = "YKL-40 is a 40 kDa secreted glycoprotein belonging to the family of 'mammalian chitinase-like proteins', but without chitinase activity. YKL-40 has a proliferative effect on fibroblasts, chondrocytes and synoviocytes, and chemotactic effect on endothelium and vascular smooth muscle cells. Elevated YKL-40 levels are found in serum of patients with diseases characterized by inflammation, fibrosis and tissue remodeling. Several studies have reported that high serum YKL-40 levels in patients with cancer are associated with poor prognosis. YKL-40 expression is strongly elevated in serum and biopsy material from glioblastomas patients. We investigated the expression of YKL-40 in three human malignant glioma cell lines exposed to different types of stress. Whereas a polymerase chain reaction transcript was detectable in all three cell lines, only U87 produced measurable amounts of YKL-40 protein. In U87, hypoxia and ionizing radiation induced a significant increase in YKL-40 after 24-48 h. The hypoxic induction of YKL-40 was independent of HIF1. Etoposide, ceramide, serum depletion and confluence all led to elevated YKL-40. Inhibition of p53 augmented the YKL-40 expression indicating that YKL-40 is attenuated by p53. In contrast, both basic fibroblast growth factor and tumor necrosing factor-alpha repressed YKL-40. These are the first data on regulation of YKL-40 in cancer cells. Diverse types of stress resulted in YKL-40 elevation, which strongly supports an involvement of YKL-40 in the malignant phenotype as a cellular survival factor in an adverse microenvironment.",
author = "Nanna Junker and Johansen, {Julia S} and Hansen, {Lasse T} and Lund, {Eva L} and Kristjansen, {Paul E G}",
note = "Keywords: Brain Neoplasms; Cell Hypoxia; Cell Survival; Enzyme-Linked Immunosorbent Assay; Gene Expression Regulation, Neoplastic; Glioblastoma; Glycoproteins; Humans; Oxidative Stress; Phenotype; Reverse Transcriptase Polymerase Chain Reaction; Tumor Cells, Cultured",
year = "2005",
doi = "10.1111/j.1349-7006.2005.00026.x",
language = "English",
volume = "96",
pages = "183--90",
journal = "Cancer Science",
issn = "1347-9032",
publisher = "Japanese Cancer Association",
number = "3",
}