Identification of prognostic values defined by copy number variation, mRNA and protein expression of LANCL2 and EGFR in glioblastoma patients.

BACKGROUND: Epidermal growth factor receptor (EGFR) and lanthionine synthetase C-like 2 (LanCL2) genes locate in the same amplicon, and co-amplification of EGFR and LANCL2 is frequent in glioblastoma. However, the prognostic value of LANCL2 and EGFR co-amplification, and their mRNA and protein expression in glioblastoma remain unclear yet. METHODS: This study analyzed the prognostic values of the copy number variations (CNVs), mRNA and protein expression of LANCL2 and EGFR in 575 glioblastoma patients in TCGA database and 100 glioblastoma patients in tumor banks of the Shenzhen Second People's Hospital and the Sun Yat-sen University Cancer Center. RESULTS: The amplification of LANCL2 or EGFR, and their co-amplification were frequent in glioblastoma of TCGA database and our tumor banks. A significant correlation was found between the CNVs of LANCL2 and EGFR (p < 0.001). CNVs of LANCL2 or EGFR were significantly correlated with IDH1/2 mutation but not MGMT promoter methylation. Multivariate analysis showed that LANCL2 amplification was significantly correlated with reduced overall survival (OS) in younger (< 60 years) glioblastoma patients of TCGA database (p = 0.043, HR = 1.657) and our tumor banks (p = 0.018, HR = 2.199). However, LANCL2 or EGFR amplification, and their co-amplification had no significant impact on OS in older (≥ 60 years) or IDH1/2-wild-type glioblastoma patients. mRNA and protein overexpression of LANCL2 and EGFR was also frequently found in glioblastoma. The mRNA expression rather than the protein expression of LANCL2 and EGFR was positively correlated (p < 0.001). However, mRNA or protein expression of EGFR and LANCL2 was not significantly correlated with OS of glioblastoma patients. The protein expression level of LANCL2, rather than EGFR, was elevated in relapsing glioblastoma, compared with newly diagnosed glioblastoma. In addition, the intracellular localization of LanCL2, not EGFR, was associated with the grade of gliomas. CONCLUSIONS: Taken together, amplification and mRNA overexpression of LANCL2 and EGFR, and their co-amplification and co-expression were frequent in glioblastoma patients. Our findings suggest that amplification of LANCL2 and EGFR were the independent diagnostic biomarkers for glioblastoma patients, and LANCL2 amplification was a significant prognostic factor for OS in younger glioblastoma patients.

Synergism between the phosphatidylinositol 3-kinase p110ß isoform inhibitor AZD6482 and the mixed lineage kinase 3 inhibitor URMC-099 on the blockade of glioblastoma cell motility and focal adhesion formation.

BACKGROUND: Glioblastoma multiforme, the most aggressive and malignant primary brain tumor, is characterized by rapid growth and extensive infiltration to neighboring normal brain parenchyma. Our previous studies delineated a crosstalk between PI3K/Akt and JNK signaling pathways, and a moderate anti-glioblastoma synergism caused by the combined inhibition of PI3K p110ß (PI3Kß) isoform and JNK. However, this combination strategy is not potent enough. MLK3, an upstream regulator of ERK and JNK, may replace JNK to exert stronger synergism with PI3Kß. METHODS: To develop a new combination strategy with stronger synergism, the expression pattern and roles of MLK3 in glioblastoma patient's specimens and cell lines were firstly investigated. Then glioblastoma cells and xenografts in nude mice were treated with the PI3Kß inhibitor AZD6482 and the MLK3 inhibitor URMC-099 alone or in combination to evaluate their combination effects on tumor cell growth and motility. The combination effects on cytoskeletal structures such as lamellipodia and focal adhesions were also evaluated. RESULTS: MLK3 protein was overexpressed in both newly diagnosed and relapsing glioblastoma patients' specimens. Silencing of MLK3 using siRNA duplexes significantly suppressed migration and invasion, but promoted attachment of glioblastoma cells. Combined inhibition of PI3Kß and MLK3 exhibited synergistic inhibitory effects on glioblastoma cell proliferation, migration and invasion, as well as the formation of lamellipodia and focal adhesions. Furthermore, combination of AZD6482 and URMC-099 effectively decreased glioblastoma xenograft growth in nude mice. Glioblastoma cells treated with this drug combination showed reduced phosphorylation of Akt and ERK, and decreased protein expression of ROCK2 and Zyxin. CONCLUSION: Taken together, combination of AZD6482 and URMC-099 showed strong synergistic anti-tumor effects on glioblastoma in vitro and in vivo. Our findings suggest that combined inhibition of PI3Kß and MLK3 may serve as an attractive therapeutic approach for glioblastoma multiforme.

Overexpression of EP300-interacting inhibitor of differentiation 3 predicts poor prognosis in patients with glioblastoma multiforme.

EP300-interacting inhibitor of differentiation 3 (EID3) is a member of the IED family and has been associated with tumorigenesis and tumor development in different cancer types. However, the role of EID3 in glioblastoma multiforme (GBM) prognosis is not clear. Whole transcriptome sequencing data of 249 and 149 GBM patients were collected from the Chinese Glioma Genome Atlas (CGGA) and The Cancer Genome Atlas (TCGA) database respectively. The correlation between EID3 expression and overall survival (OS)/clinical pathologic features of GBM patients was investigated. Based on the Wilcoxon rank-sum test, EID3 expression in GBM tissues was significantly lower than in normal brain tissues (P < 0.001), and significantly higher than in LGG (low-grade glioma) (P < 0.001).There was a significant correlation between high EID3 expression with poor OS in CGGA (P = 0.049) and TCGA data (P = 0.024). Gene set enrichment analysis (GSEA) data analysis revealed a significant difference (FDR < 0.25, NOM p-value < 0.05) in the enrichment of MSigDB Collection (h.all.v6.2.symbols.gmt). A total of eight enriched pathways were identified in the high EID3 expression group, including Myc Targets V1, Kras signaling DN, and DNA repair pathways. Multivariate Cox regression analysis indicated that high expression of EID3 correlated with poor OS (P = 0.032, HR = 1.41, CI: 1.03-1.90). We conclude that EID3 could serve as an independent factor for predicting the prognosis of patients with GBM. Moreover, it is associated with GBM development through the regulation of the Myc Targets, Kras signaling DN, and DNA repair pathways.