Glioma exosomal microRNA-148a-3p promotes tumor angiogenesis through activating the EGFR/MAPK signaling pathway via inhibiting ERRFI1.

BACKGROUND: Glioma is the most frequent and lethal primary brain malignancy. Amounting evidence has highlighted the importance of exosomal microRNAs (miRNAs or miRs) in this malignancy. This study aimed to investigate the regulatory role of exosomal miR-148a-3p in glioma. METHODS: Bioinformatics analysis was firstly used to predict the target genes of miR-148a-3p. Exosomes were then extracted from normal human astrocytes and glioma cells. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was applied to determine the expression patterns of miR-148a-3p and ERBB receptor feedback inhibitor 1 (ERRFI1). Dual-luciferase reporter gene assay was applied to verify the direct binding between miR-148a-3p and ERRFI1. Cell counting kit-8 and tube formation assays were further conducted to assess the proliferation and angiogenic properties of human umbilical vein endothelial cells (HUVECs) in the co-culture system with exosomes. Lastly, glioma tumor models were established in BALB/c nude mice to study the role of exosomal miR-148a-3p in vivo. RESULTS: miR-148a-3p was highly expressed, while ERRFI1 was poorly expressed in glioma. miR-148a-3p was found to be enriched in glioma cells-derived exosomes and could be transferred to HUVECs via exosomes to promote their proliferation and angiogenesis. ERRFI1 was identified as a target gene of miR-148a-3p. In addition, miR-148a-3p activated the epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK) signaling pathway by inhibiting ERRFI1. In the co-culture system, our data demonstrated that glioma cells-derived exosomal miR-148a-3p down-regulated ERRFI1 and activated the EGFR/MAPK signaling pathway, so as to promote cell proliferation and angiogenesis. In vivo experimentation further demonstrated that this mechanism was responsible for the promotive role of exosomal miR-148a-3p in tumorigenesis and angiogenesis. CONCLUSION: Taken together, glioma-derived exosomal miR-148a-3p promoted tumor angiogenesis through activation of the EGFR/MAPK signaling pathway by ERRFI1 inhibition.

Supratentorial Cortical Ependymomas: A Retrospective Series of 13 Cases at a Single Center.

OBJECTIVE: Cortical ependymomas (CEs), supratentorial ependymomas that selectively involve the cerebral cortex, are relatively rare neoplasms that have not been extensively described. The purpose of our study was to identify the clinical features, radiologic characteristics, and treatment of a series of such tumors. METHODS: Thirteen patients with CEs from our hospital were included in this study. Epidemiologic characteristics, clinical features, imaging findings, treatment methods, and clinical outcomes were reviewed retrospectively. RESULTS: The patients consisted of 7 men and 6 women with mean age of 31.1 ± 23.2 years (range, 4-74 years). The most common clinical manifestation was seizure (n = 11; 85%), followed by headache (n = 2; 15%). None of the tumors were incidentally detected. Eight CEs were located in the right hemisphere and 5 in the left side. The 2 most common tumor locations were the frontal (n = 5; 38%) and parietal lobe (n = 5; 38%). All patients underwent surgical resection. Gross total resection was achieved in 12 patients (92%), and subtotal resection was performed in 1 patient (8%). Ten of the 11 patients who presented with seizure are seizure-free after surgery (91% seizure-free rate). According to the World Health Organization classification system, 9 tumors (69%) were Grade II (ependymoma) and 4 (31%) were Grade III (anaplastic ependymoma). The mean follow-up was 52 months (range, 20-88 months). No recurrence was observed in patients with Grade II CEs. Of 4 patients with Grade III CEs, 2 (50%) suffered from tumor recurrence after initial treatment. CONCLUSIONS: CEs are a rare subset of supratentorial ependymomas that selectively involve the cerebral cortex. Most CEs are low grade and present with seizures. Anaplastic CEs show a greater recurrence rate and a relatively poor prognosis. Gross total resection with or without adjuvant radiotherapy is currently the optimal treatment for CEs. CEs seem to have a more favorable prognosis than other supratentorial ependymomas.

Supratentorial extraventricular ependymomas: A retrospective study focused on long-term outcomes and prognostic factors.

OBJECTIVE: Supratentorial extraventricular ependymomas are relatively rare. Long-term outcomes and prognostic factor for this rare tumor have not been well established. The purpose of this study was to demonstrateprogression-freesurvival(PFS),overallsurvival(OS), and prognostic factors of such tumor. PATIENTS AND METHODS: Fifty-five patients with supratentorial extraventricular ependymomas from our hospital were included in this study. Epidemiological characteristics, clinical features, treatment,long-term outcomes, and prognostic factors for PFS and OS were reviewed retrospectively. RESULTS: The patients consisted of 30 males and 25 females with mean age of 30.0 ±â€¯23.6 years (range, 1-74 years). Twenty-nine tumors were located in the right hemisphere, and 26 in the left side. The 2 most common tumor locations were the frontal (n = 19; 35%) and parietal lobe (n = 11; 20%). All patients underwent surgical resection. Gross-total resection (GTR) was achieved in 42 cases (76%) and subtotal resection (STR) was performed in 13 patients (24%). According to the WHO classification system, 38 tumors (69%) were Grade III (anaplastic ependymoma), and 17 (31%) were Grade II (ependymoma). Three-,5-, and 10 year PFS rates were 60%, 49%, and 36%, respectively. Three-,5-, and 10 year OS rates were 79%, 64%, and 49%, respectively. EOR and tumor grade were identified as prognostic factors for PFS and OS on univariate analysis, multivariate analysis, and Kaplan-Meierlog-rank testing. Subtotal resection (STR) predicted a worse PFS (HR = 4.808; 95%, 1.942-11.905; P = .001) and OS (HR = 5.650; 95%, 2.114-15.152; P = .001). WHO Grade III tumors also had worse PFS (HR = 3.922; 95%, 1.429-18.182; P = .012) and OS (HR = 6.329; 95%, 1.328-30.303; P = 0.021). For patients with tumor recurrence, reoperation was significant prognostic factors for OS (HR = 2.091; 95%, 0.939-4.654; p = .000). Age, sex, tumor side, and postoperativeradiotherapy were not prognostic factors for PFS and OS. CONCLUSIONS: Most supratentorial extraventricular ependymomas are WHO grade III tumors. STRandWHO Grade III pathology predicted worse PFS and OS. Gross-total resection remains the optimal treatment for patients with supratentorial extraventricular ependymoma. Reoperation should be considered first in cases of recurrence. The role of postoperative radiotherapy as an adjuvant treatment for supratentorial extraventricular ependymoma needs further investigation.