Jian-Wei Wei1, Jin-Quan Cai2, Chuan Fang3, Yan-Li Tan4, Kai Huang1, Chao Yang1, Qun Chen2, Chuan-Lu Jiang2, Chun-Sheng Kang1. 1. Department of Neurosurgery, Laboratory of Neuro-oncology, Tianjin Neurological Institute, Key Laboratory of Post-Neuro injury Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Medical University General Hospital, Tianjin, China. 2. Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, NanGang District, Harbin, Heilongjiang Province, China. 3. Department of Neurosurgery, The Hospital affiliated to Hebei University, Baoding, China. 4. College of Fundamental Medicine, Hebei University, Baoding, China.
Abstract
BACKGROUND AND AIMS: EGFRvIII is the most prevalent glioblastoma mutation, occurring in more than 25% of glioblastomas. EGFRvIII cells release microvesicles that contain proteins, miRNAs, and mRNAs that enhance the growth and survival of surrounding tumor cells. However, little is known about the maturation process and regulatory mechanisms of secreted vesicles in EGFRvIII cells. METHODS: Signal peptide peptidase (SPP) provides a fascinating mechanism for protein cleavage and subsequent dislocation in the endoplasmic reticulum transmembrane domain. RESULTS: In this study, we reported that SPP facilitates the secretion of cytokines in vitro and promotes tumor progression in mice. Human cytokine antibody arrays revealed that EGFRvIII secreted higher levels of cytokines, but these levels were significantly reduced following SPP knockdown, suggesting that cytokines in EGFRvIII secretion profiles play important roles in GBM development. Identical results were confirmed in intracellular maturation tracking of TGF-β1 in mouse serum. Clinically, analyses of GBM patient data from the database revealed that HM13 expression was closely related to patient prognosis and survival, suggesting an influence by the secreted vesicles of EGFRvIII tumor cells. CONCLUSIONS: Collectively, our study identifies that SPP affects EGFRvIII secretion profiles and thus promotes tumor progression, providing further understanding of the formation of secreted vesicles and driving role of EGFRvIII in GBM.
BACKGROUND AND AIMS: EGFRvIII is the most prevalent glioblastoma mutation, occurring in more than 25% of glioblastomas. EGFRvIII cells release microvesicles that contain proteins, miRNAs, and mRNAs that enhance the growth and survival of surrounding tumor cells. However, little is known about the maturation process and regulatory mechanisms of secreted vesicles in EGFRvIII cells. METHODS:Signal peptide peptidase (SPP) provides a fascinating mechanism for protein cleavage and subsequent dislocation in the endoplasmic reticulum transmembrane domain. RESULTS: In this study, we reported that SPP facilitates the secretion of cytokines in vitro and promotes tumor progression in mice. Human cytokine antibody arrays revealed that EGFRvIII secreted higher levels of cytokines, but these levels were significantly reduced following SPP knockdown, suggesting that cytokines in EGFRvIII secretion profiles play important roles in GBM development. Identical results were confirmed in intracellular maturation tracking of TGF-β1 in mouse serum. Clinically, analyses of GBM patient data from the database revealed that HM13 expression was closely related to patient prognosis and survival, suggesting an influence by the secreted vesicles of EGFRvIII tumor cells. CONCLUSIONS: Collectively, our study identifies that SPP affects EGFRvIII secretion profiles and thus promotes tumor progression, providing further understanding of the formation of secreted vesicles and driving role of EGFRvIII in GBM.