title: Preferential expression of functional IL-17R in glioma stem cells: potential role in self-renewal.
abstract: Gliomas are the most common primary brain tumor and one of the most lethal solid tumors. Mechanistic studies into identification of novel biomarkers are needed to develop new therapeutic strategies for this deadly disease. The objective for this study was to explore the potential direct impact of IL-17-IL-17R interaction in gliomas. Immunohistochemistry and flow cytometry analysis of 12 tumor samples obtained from patients with high grade gliomas revealed that a considerable population (2-19%) of cells in all malignant gliomas expressed IL-17RA, with remarkable co-expression of the glioma stem cell (GSC) markers CD133, Nestin, and Sox2. IL-17 enhanced the self-renewal of GSCs as determined by proliferation and Matrigel® colony assays. IL-17 also induced cytokine/chemokine (IL-6, IL-8, interferon-γ-inducible protein [IP-10], and monocyte chemoattractant protein-1 [MCP-1]) secretion in GSCs, which were differentially blocked by antibodies against IL-17R and IL-6R. Western blot analysis showed that IL-17 modulated the activity of signal transducer and activator of transcription 3 (STAT3), nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB), glycogen synthase kinase-3β (GSK-3β) and β-catenin in GSCs. While IL-17R-mediated secretion of IL-6 and IL-8 were significantly blocked by inhibitors of NF-κB and STAT3; NF-κB inhibitor was more potent than STAT3 inhibitor in blocking IL-17-induced MCP-1 secretion. Overall, our results suggest that IL-17-IL-17R interaction in GSCs induces an autocrine/paracrine cytokine feedback loop, which may provide an important signaling component for maintenance/self-renewal of GSCs via constitutive activation of both NF-κB and STAT3. The results also strongly implicate IL-17R as an important functional biomarker for therapeutic targeting of GSCs.
authors.affiliation: Department of Neurosurgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Prahlad
authors.initials: P
authors.lastname: Parajuli
authors.affiliation: Department of Neurosurgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Rohit
authors.initials: R
authors.lastname: Anand
authors.affiliation: Department of Neurosurgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Chandramouli
authors.initials: C
authors.lastname: Mandalaparty
authors.affiliation: Department of Neurosurgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Raviteja
authors.initials: R
authors.lastname: Suryadevara
authors.affiliation: Department of Neurosurgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Preethi U
authors.initials: PU
authors.lastname: Sriranga
authors.affiliation: Department of Neurosurgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Sharon K
authors.initials: SK
authors.lastname: Michelhaugh
authors.affiliation: Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI, USA.
authors.forename: Simona
authors.initials: S
authors.lastname: Cazacu
authors.affiliation: Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Finniss
authors.affiliation: Department of Oncology, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Archana
authors.initials: A
authors.lastname: Thakur
authors.affiliation: Department of Oncology, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.|Departments of Internal Medicine, Immunology and Microbiology and Pediatrics, Wayne State University, Detroit, MI, USA.
authors.forename: Lawrence G
authors.initials: LG
authors.lastname: Lum
authors.affiliation: Department of Oncology, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Dana
authors.initials: D
authors.lastname: Schalk
authors.affiliation: Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI, USA.
authors.forename: Chaya
authors.initials: C
authors.lastname: Brodie
authors.affiliation: Department of Neurosurgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.|Department of Oncology, Wayne State University and Karmanos Cancer Institute, Detroit, MI, USA.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Mittal
mesh_terms: D000368:Aged; D049109:Cell Proliferation / Q000502:physiology; D005260:Female; D005910:Glioma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D020381:Interleukin-17 / Q000096:biosynthesis*; D008297:Male; D008875:Middle Aged; D016328:NF-kappa B / Q000378:metabolism; D015398:Signal Transduction
chemical_list: C508717:IL17A protein, human; D020381:Interleukin-17; D016328:NF-kappa B
keywords: IL-17; IL-17R; IL-6; NF-κB; glioma stem cells (GSCs)