Golgi Membrane Protein 1 (GOLM1), a protein involved in the trafficking of proteins through the Golgi apparatus, has been shown to be oncogenic in a variety of human cancers. Here, we examined the role of GOLM1 in the development of human glioma. qRT-PCR, immunohistochemistry, and western blot analysis were performed to evaluate GOLM1 levels in cell lines and a cohort of primary human glioma and non-neoplastic brain tissue samples. Glioma cell lines were modified with lentiviral constructs expressing short hairpin RNAs targeting GOLM1 or overexpressing the protein to assess function in proliferation, viability, and migration and invasion in vitro using EdU, CCK8, clone-forming, Transwell assays, 3D tumor spheroid invasion assay and in vivo in orthotopic implantations. Protein lysates were used to screen a membrane-based antibody array to identify kinases mediated by GOLM1. Specific inhibitors of PDGFRα (AG1296) and AKT (MK-2206) were used to examine the regulation of PDGFA/PDGFRα on GOLM1 and the underlying pathway respectively. qRT-PCR, immunohistochemistry and western blot analysis revealed GOLM1 expression to be elevated in glioma tissues and cell lines. Silencing of GOLM1 attenuated proliferation, migration, and invasion of U251, A172 and P3#GBM (primary glioma) cells, while overexpression of GOLM1 enhanced malignant behavior of U87MG cells. We further demonstrated that activation of AKT is the driving force of GOLM1-promoted glioma progression. The last finding of this research belongs to the regulation of PDGFA/PDGFRα on GOLM1, while GOLM1 was also a key element of PDGFA/PDGFRα-mediated activation of AKT, as well as the progression of glioma cells. PDGFA/PDGFRα-regulated GOLM1 promotes glioma progression possibly through activation of a key signaling kinase, AKT. GOLM1 interference may therefore provide a novel therapeutic target and improve the efficacy of glioma treatment, particularly in the case of the proneural molecular subtype of human glioma.

Background: Radiotherapy constitutes a standard arm of therapy in the multimodal treatment of patients with glioblastoma (GBM). Ironically, studies have recently revealed that radiation can augment malignant progression, by promoting migration and invasion, which make the disease especially difficult to cure. Here, we investigated the anticancer effects of YM155, a purported radiosensitizer, in GBM cell lines. Methods: GBM cell lines U251 and U87 were treated with YM155 to assess cytotoxicity and activity of the molecule in vitro. Nude mice were implanted with cells to generate orthotopic xenografts for in vivo studies. Response of cells to treatment was examined using cell viability, immunofluorescence, wound healing, and the Transwell invasion assay. Molecules potentially mediating response were examined through western blot analysis, phospho-kinase arrays, and qPCR. Cells were transfected with siRNA knockdown and gene expression constructs to identify molecular mediators of response. Results: YM155 reduced viability of U251 and U87 cells and enhanced radiosensitivity through inhibition of homologous recombination. Besides, YM155 decreased invasion caused by radiation and led to expression changes in molecular markers associated with EMT. STAT3 was one of 10 molecules identified on a phosphokinase array exhibiting significant change in phosphorylation under YM155 treatment. Transfection with STAT3 siRNAs or expression constructs demonstrated that EMT changes were achieved by inhibiting the phosphorylation of STAT3 and were survivin-independent. Finally, combining YM155 and radiation in orthotopic xenografts reduced growth and prolonged overall survival of animals. Conclusions: YM155 decreased radiation-induced invasion in GBM cell lines in vitro and in vivo through inhibition of STAT3.

The coiled-coil domain is a structural motif found in proteins that participate in a variety of biological processes. Aberrant expression of such proteins has been shown to be associated with the malignant behavior of human cancers. In this study, we investigated the role of a specific family member, coiled-coil domain containing 109B (CCDC109B), in human gliomas. We confirmed that CCDC109B was highly expressed in high grade gliomas (HGG; WHO III–IV) using immunofluorescence, western blot analysis, immunohistochemistry (IHC) and open databases. Through Cox regression analysis of The Cancer Genome Atlas (TCGA) database, we found that the expression levels of CCDC109B were inversely correlated with patient overall survival and it could serve as a prognostic marker. Then, a serious of cell functional assays were performed in human glioma cell lines, U87MG and U251, which indicated that silencing of CCDC109B attenuated glioma proliferation and migration/invasion both in vitro and in vivo. Notably, IHC staining in primary glioma samples interestingly revealed localization of elevated CCDC109B expression in necrotic areas which are typically hypoxic. Moreover, small interfering RNA (siRNA) and specific inhibiters of HIF1α led to decreased expression of CCDC109B in vitro and in vivo. Transwell assay further showed that CCDC109B is a critical factor in mediating HIF1α-induced glioma cell migration and invasion. Our study elucidated a role for CCDC109B as an oncogene and a prognostic marker in human gliomas. CCDC109B may provide a novel therapeutic target for the treatment of human glioma.

Long noncoding RNAs (lncRNAs) have emerged as potential prognostic markers in various human cancers as they participate in many malignant behaviors. However, the value of lncRNAs as prognostic markers among diverse human cancers is still under investigation, and a systematic signature based on these transcripts that related to pan-cancer prognosis has yet to be reported. In this study, we proposed a framework to incorporate statistical power, biological rationale and machine learning models for pan-cancer prognosis analysis. The framework identified a 5-lncRNA signature (ENSG00000206567, PCAT29, ENSG00000257989, LOC388282, and LINC00339) from TCGA training studies (n=1,878). The identified lncRNAs are significantly associated (all P1.48E-11) with overall survival (OS) of the TCGA cohort (n=4,231). The signature stratified the cohort into low- and high-risk groups with significantly distinct survival outcomes (median OS of 9.84 years versus 4.37 years, log-rank P=1.48E-38) and achieved a time-dependent ROC/AUC of 0.66 at 5 years. After routine clinical factors involved, the signature demonstrated a better performance for long-term prognostic estimation (AUC of 0.72). Moreover, the signature was further evaluated on two independent external cohorts (TARGET, n=1,122; CPTAC, n=391; National Cancer Institute) which yielded similar prognostic values (AUC of 0.60 and 0.75; log-rank P=8.6E-09 and P=2.7E-06). An indexing system was developed to map the 5-lncRNA signature to prognoses of pan-cancer patients. In silico functional analysis indicated that the lncRNAs are associated with common biological processes driving human cancers. The five lncRNAs, especially ENSG00000206567, ENSG00000257989 and LOC388282 that never reported before, may serve as viable molecular targets common among diverse cancers.