title: Glioma IL13Rα2 is associated with mesenchymal signature gene expression and poor patient prognosis.
abstract: A major challenge for successful immunotherapy against glioma is the identification and characterization of validated targets. We have taken a bioinformatics approach towards understanding the biological context of IL-13 receptor α2 (IL13Rα2) expression in brain tumors, and its functional significance for patient survival. Querying multiple gene expression databases, we show that IL13Rα2 expression increases with glioma malignancy grade, and expression for high-grade tumors is bimodal, with approximately 58% of WHO grade IV gliomas over-expressing this receptor. By several measures, IL13Rα2 expression in patient samples and low-passage primary glioma lines most consistently correlates with the expression of signature genes defining mesenchymal subclass tumors and negatively correlates with proneural signature genes as defined by two studies. Positive associations were also noted with proliferative signature genes, whereas no consistent associations were found with either classical or neural signature genes. Probing the potential functional consequences of this mesenchymal association through IPA analysis suggests that IL13Rα2 expression is associated with activation of proinflammatory and immune pathways characteristic of mesenchymal subclass tumors. In addition, survival analyses indicate that IL13Rα2 over-expression is associated with poor patient prognosis, a single gene correlation ranking IL13Rα2 in the top ~1% of total gene expression probes with regard to survival association with WHO IV gliomas. This study better defines the functional consequences of IL13Rα2 expression by demonstrating association with mesenchymal signature gene expression and poor patient prognosis. It thus highlights the utility of IL13Rα2 as a therapeutic target, and helps define patient populations most likely to respond to immunotherapy in present and future clinical trials.
authors.affiliation: Department of Cancer Immunotherapy & Tumor Immunology and Hematology & Hematopoietic Cell Transplantation, Beckman Research Institute and City of Hope National Medical Center, Duarte, California, United States of America.
authors.forename: Christine E
authors.initials: CE
authors.lastname: Brown
authors.forename: Charles D
authors.initials: CD
authors.lastname: Warden
authors.forename: Renate
authors.initials: R
authors.lastname: Starr
authors.forename: Xutao
authors.initials: X
authors.lastname: Deng
authors.forename: Behnam
authors.initials: B
authors.lastname: Badie
authors.forename: Yate-Ching
authors.initials: YC
authors.lastname: Yuan
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Forman
authors.forename: Michael E
authors.initials: ME
authors.lastname: Barish
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000235:genetics*; D001932:Brain Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D053263:Gene Regulatory Networks; D005910:Glioma / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D006801:Humans; D053663:Interleukin-13 Receptor alpha2 Subunit / Q000235:genetics*; D008297:Male; D008648:Mesoderm / Q000378:metabolism; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate; D059467:Transcriptome; D014407:Tumor Cells, Cultured; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D053663:Interleukin-13 Receptor alpha2 Subunit