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© 2020 The Authors., The distribution and role of tumor-infiltrating leucocytes in glioblastoma (GBM) remain largely unknown. Here, we investigated the cellular composition of 55 primary (adult) GBM samples by flow cytometry and correlated the tumor immune profile with patient features at diagnosis and outcome. GBM single-cell suspensions were stained at diagnosis (n = 44) and recurrence following radiotherapy and chemotherapy (n = 11) with a panel of 8-color monoclonal antibody combinations for the identification and enumeration of (GFAPCD45) tumor and normal astrocytic cells, infiltrating myeloid cells —i.e. microglial and blood-derived tumor-associated macrophages (TAM), M1-like, and M2-like TAM, neutrophils. and myeloid-derived suppressor cells (MDSC)— and tumor-infiltrating lymphocytes (TIL) —i.e. CD3T-cells and their TCD4, TCD8, TCD4CD8, and (CD25CD127) regulatory (T-regs) subsets, (CD19CD20) B-cells, and (CD16) NK-cells—. Overall, GBM samples consisted of a major population (mean ± 1SD) of tumor and normal astrocytic cells (73% ± 16%) together with a significant but variable fraction of immune cells (24% ± 18%). Within myeloid cells, TAM predominated (13% ± 12%) including both microglial cells (10% ± 11%) and blood-derived macrophages (3% ± 5%), in addition to a smaller proportion of neutrophils (5% ± 9%) and MDSC (4% ± 8%). Lymphocytes were less represented and mostly included TCD4 (0.5% ± 0.7%) and TCD8 cells (0.6% ± 0.7%), together with lower numbers of TCD4CD8 T-cells (0.2% ± 0.4%), T-regs (0.1% ± 0.2%), B-lymphocytes (0.1% ± 0.2%) and NK-cells (0.05% ± 0.05%). Overall, three distinct immune profiles were identified: cases with a minor fraction of leucocytes, tumors with a predominance of TAM and neutrophils, and cases with mixed infiltration by TAM, neutrophils, and T-lymphocytes. Untreated GBM patients with mixed myeloid and lymphoid immune infiltrates showed a significantly shorter patient overall survival versus the other two groups, in the absence of gains of the EGFR gene (p = 0.02). Here we show that immune cell infiltrates are systematically present in GBM, with highly variable levels and immune profiles. Patients with mixed myeloid and T-lymphoid infiltrates showed a worse outcome., Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain and fondos FEDER, Grant/Award Number: CB16/12/00400 and ISCIII PI16/0476; Consejería de Sanidad Junta de Castilla y León, Gerencia Regional de Salud, Spain, Grant/Award Number: GRS2049/A/19

Diagnosis and classification of gliomas mostly relies on histopathology and a few genetic markers. Here we interrogated microarray gene expression profiles (GEP) of 268 diffuse astrocytic gliomas—33 diffuse astrocytomas (DA), 52 anaplastic astrocytomas (AA) and 183 primary glioblastoma (GBM)—based on multivariate analysis, to identify discriminatory GEP that might support precise histopathological tumor stratification, particularly among inconclusive cases with II–III grade diagnosed, which have different prognosis and treatment strategies. Microarrays based GEP was analyzed on 155 diffuse astrocytic gliomas (discovery cohort) and validated in another 113 tumors (validation set) via sequential univariate analysis (pairwise comparison) for discriminatory gene selection, followed by nonnegative matrix factorization and canonical biplot for identification of discriminatory GEP among the distinct histological tumor subtypes. GEP data analysis identified a set of 27 genes capable of differentiating among distinct subtypes of gliomas that might support current histological classification. DA + AA showed similar molecular profiles with only a few discriminatory genes overexpressed (FSTL5 and SFRP2) and underexpressed (XIST, TOP2A and SHOX2) in DA vs AA and GBM. Compared to DA + AA, GBM displayed underexpression of ETNPPL, SH3GL2, GABRG2, SPX, DPP10, GABRB2 and CNTN3 and overexpression of CHI3L1, IGFBP3, COL1A1 and VEGFA, among other differentially expressed genes., MG-T, AO and MDT were supported by the following Grants: CB16/12/00400 (CIBER-ONC, Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain and FONDOS FEDER), ISCIII PI16/0476 (Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain) and GRS2049/A/19 (Consejería de Sanidad Junta de Castilla y León, Gerencia Regional de Salud, Spain).

This article belongs to the Special Issue Brain Tumors., [Background]: The prognostic impact of the expression profile of genes recurrently amplified in glioblastoma multiforme (GBM) remains controversial., [Methods]: We investigated the RNA gene expression profile of epidermal growth factor receptor (EGFR), cyclin-dependent kinase 4 (CDK4), murine doble minute 4 (MDM4), and platelet derived growth factor receptor alpha (PDGFRA) in 83 primary GBM tumors vs. 42 normal brain tissue samples. Interphase FISH (iFISH) analysis for the four genes, together with analysis of intragenic deletions in EGFR and PDGFRA, were evaluated in parallel at the DNA level. As validation cohort, publicly available RNA gene expression data on 293 samples from 10 different GBM patient series were also studied., [Results]: At the RNA level, CDK4 was the most frequently overexpressed gene (90%) followed by EGFR (58%) and PDGFRA (58%). Chromosome 7 copy number alterations, i.e., trisomy (49%) and polysomy (44%), showed no clear association with EGFR gene expression levels. In turn, intragenic EGFR deletions were found in 39 patients (47%), including EGFRvIII (46%) in association with EGFRvIVa (4%), EGFRvII (2%) or other EGFR deletions (3%) and PDGFRA deletion of exons 8–9 was found in only two tumors (2%)., [Conclusions]: Overall, none of the gene expression profiles and/or intragenic EGFR deletions showed a significant impact on overall survival of GBM supporting the notion that other still unraveled features of the disease might play a more relevant prognostic role in GBM, This research was funded by Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Ministerio de Economía y Competitividad (RD12/0036/0048, AES PI16/00476-FONDOS FEDER and CB16/12/00400).

Purpose: Despite the wide use of antiangiogenic drugs in the clinical setting, predictive biomarkers of response to these drugs are still unknown. Experimental Design: We applied whole-exome sequencing of matched germline and basal plasma cell-free DNA samples (WES-cfDNA) on a RAS/BRAF/PIK3CA wild-type metastatic colorectal cancer patient with primary resistance to standard treatment regimens, including inhibitors to the VEGF:VEGFR2 pathway. We performed extensive functional experiments, including ectopic expression of VEGFR2 mutants in different cell lines, kinase and drug sensitivity assays, and cell- and patient-derived xenografts. Results: WES-cfDNA yielded a 77% concordance rate with tumor exome sequencing and enabled the identification of the KDR/VEGFR2 L840F clonal, somatic mutation as the cause of therapy refractoriness in our patient. In addition, we found that 1% to 3% of samples from cancer sequencing projects harbor KDR somatic mutations located in protein residues frequently mutated in other cancer-relevant kinases, such as EGFR, ABL1, and ALK. Our in vitro and in vivo functional assays confirmed that L840F causes strong resistance to antiangiogenic drugs, whereas the KDR hot-spot mutant R1032Q confers sensitivity to strong VEGFR2 inhibitors. Moreover, we showed that the D717V, G800D, G800R, L840F, G843D, S925F, R1022Q, R1032Q, and S1100F VEGFR2 mutants promote tumor growth in mice. Conclusions: Our study supports WES-cfDNA as a powerful platform for portraying the somatic mutation landscape of cancer and discovery of new resistance mechanisms to cancer therapies. Importantly, we discovered that VEGFR2 is somatically mutated across tumor types and that VEGFR2 mutants can be oncogenic and control sensitivity/resistance to antiangiogenic drugs. Clin Cancer Res; 24(15); 3550–9. ©2018 AACR.

Several classification systems have been proposed to address genomic heterogeneity of glioblastoma multiforme, but they either showed limited prognostic value and/or are difficult to implement in routine diagnostics. Here we propose a prognostic stratification model for these primary tumors based on tumor gene amplification profiles, that might be easily implemented in routine diagnostics, and potentially improve the patients management. Gene amplification profiles were prospectively evaluated in 80 primary glioblastoma multiforme tumors using single-nucleotide polymorphism arrays and the results obtained validated in publicly available data from 267/347 cases. Gene amplification was detected in 45% of patients, and chromosome 7p11.2 including the EGFR gene, was the most frequently amplified chromosomal region – either alone (18%) or in combination with amplification of DNA sequences in other chromosomal regions (10% of cases). Other frequently amplified DNA sequences included regions in chromosomes 12q(10%), 4q12(7%) and 1q32.1(4%). Based on their gene amplification profiles, glioblastomas were subdivided into: i) tumors with no gene amplification (55%); ii) tumors with chromosome 7p/EGFR gene amplification (with or without amplification of other chromosomal regions) (38%); and iii) glioblastoma multiforme with a single (11%) or multiple (6%) amplified DNA sequences in chromosomal regions other than chromosome 7p. From the prognostic point of view, these amplification profiles showed a significant impact on overall survival of glioblastoma multiforme patients (p>0.001). Based on these gene amplification profiles, a risk-stratification scoring system was built for prognostic stratification of glioblastoma which might be easily implemented in routine diagnostics, and potentially contribute to improved patient management., This work was supported by RETICC RD06/0020/0035, RD06/0020/0059 and RD12/0036/0048 grants from Red Temática de Investigación Cooperativa en Cáncer (RTICC), Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, (Madrid, Spain and FONDOS FEDER), AES PI16/000476 (Instituto de Salud Carlos III, Madrid, Spain and FONDOS FEDER), GRS909A14 (JCYL) and CB16/12/00400 grant (CIBERONC, Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain and FONDOS FEDER).

In recent years, important advances have been achieved in the understanding of the molecular biology of glioblastoma multiforme (GBM); thus, complex genetic alterations and genomic profiles, which recurrently involve multiple signaling pathways, have been defined, leading to the first molecular/genetic classification of the disease. In this regard, different genetic alterations and genetic pathways appear to distinguish primary (eg, EGFR amplification) versus secondary (eg, IDH1/2 or TP53 mutation) GBM. Such genetic alterations target distinct combinations of the growth factor receptor–ras signaling pathways, as well as the phosphatidylinositol 3-kinase/phosphatase and tensin homolog/AKT, retinoblastoma/cyclin-dependent kinase (CDK) N2A-p16 INK4A , and TP53/mouse double minute (MDM) 2/MDM4/CDKN2A-p14 ARF pathways, in cells that present features associated with key stages of normal neurogenesis and (normal) central nervous system cell types. This translates into well-defined genomic profiles that have been recently classified by The Cancer Genome Atlas Consortium into four subtypes: classic, mesenchymal, proneural, and neural GBM. Herein, we review the most relevant genetic alterations of primary versus secondary GBM, the specific signaling pathways involved, and the overall genomic profile of this genetically heterogeneous group of malignant tumors.

Summary Connexin43 (CX43), a protein that forms gap junction channels and hemichannels in astrocytes, is downregulated in high-grade gliomas. Its relevance for glioma therapy has been thoroughly explored; however, its positive effects on proliferation are counterbalanced by its effects on migration and invasion. Here, we show that a cell-penetrating peptide based on CX43 (TAT-Cx43266-283) inhibited c-Src and focal adhesion kinase (FAK) and upregulated phosphatase and tensin homolog in glioma stem cells (GSCs) derived from patients. Consequently, TAT-Cx43266-283 reduced GSC motility, as analyzed by time-lapse microscopy, and strongly reduced their invasive ability. Interestingly, we investigated the effects of TAT-Cx43266-283 on freshly removed surgical specimens as undissociated glioblastoma blocks, which revealed a dramatic reduction in the growth, migration, and survival of these cells. In conclusion, a region of CX43 (amino acids 266–283) exerts an important anti-tumor effect in patient-derived glioblastoma models that includes impairment of GSC migration and invasion., Highlights • TAT-Cx43266-283 exerts anti-tumor effects in patient-derived glioblastoma models • TAT-Cx43266-283 targets Src, PTEN, and FAK • TAT-Cx43266-283 inhibits glioma stem cell migration and invasion, In this article, Arantxa Tabernero and colleagues show that a short region of Connexin43 exerts an important anti-tumor effect in patient-derived glioblastoma models that includes the impairment of glioma stem cell migration and invasion. This peptide targets important proteins for glioblastoma, such as Src, FAK, and PTEN, highlighting its relevance for therapeutic development against this incurable disease.

Introduction The expression of connexin43 (Cx43), the main gap junction channel-forming protein, is down-regulated in glioma stem cells (GSC). Our previous studies showed that a cell-penetrating peptide containing the region of Cx43 that interacts with the oncoprotein c-Src (TAT-Cx43266–283), inhibits its oncogenic activity and up-regulates the tumour suppressor PTEN. Through this pathway, TAT-Cx43266–283 reduces glioma cell proliferation and reverses the GSC phenotype. Our next goal was to uncover the mechanism of action and the effects of TAT-Cx43266–283 on the migration and invasion of human GSCs. Material and methods Human primary GSCs (G9, G12, G13, G15 and G16) were obtained from glioblastoma patients’ biopsies from the Neurosurgery Service of the Hospital Universitario de Salamanca, Spain. The migration was analysed in these primary GSCs by tracking individual cell trajectories in cultures recorded by Time-Lapse Live-cell Imaging and the invasion with Matrigel-treated transwell inserts. The same tumour biopsies were used to study the effect of TAT-Cx43266–283 on fresh undissociated tumour blocks by time-lapse microscopy. The molecular interactions were studied in G166 GSCs by pull-down assays of biotinylated TAT-Cx43266–283 (TAT-Cx43266–283-B) and Western blot analysis. Results and discussions Our results confirmed that TAT-Cx43266–283 strongly reduces the migration and invasion of human primary GSCs by inhibiting c-Src activity and up-regulating PTEN that consequently, lowers the levels of phosphorylation of focal adhesion kinase tyrosines 397, 576 and 577. In addition, fresh undissociated tumour blocks revealed a dramatic reduction on the survival of these glioblastoma cells when exposed to TAT-Cx43266–283. By pull-down assays, we showed that TAT-Cx43266–283-B recruits c-Src together with its inhibitors PTEN and Csk, confirming the proposed mechanism for Cx43. Conclusion In conclusion, TAT-Cx43266–283 exerts an important antitumor effect by inhibiting c-Src and up-regulating PTEN with the subsequent reduction in FAK phosphorylation required to establish appropriate focal adhesions for migration, proliferation and survival. This inhibition is mediated by the recruitment of the c-Src intrinsic inhibitors, PTEN and Csk. All together, these results reinforce the relevance of this sequence of Cx43 that interacts with c-Src for the development of new therapies against glioblastoma.

[Background]: Tumor recurrence remains the major clinical complication of meningiomas, the majority of recurrences occurring among WHO grade I/benign tumors. In the present study, we propose a new scoring system for the prognostic stratification of meningioma patients based on analysis of a large series of meningiomas followed for a median of >5 years. [Methods]: Tumor cytogenetics were systematically investigated by interphase fluorescence in situ hybridization in 302 meningioma samples, and the proposed classification was further validated in an independent series of cases (n = 132) analyzed by high-density (500K) single-nucleotide polymorphism (SNP) arrays. [Results]: Overall, we found an adverse impact on patient relapse-free survival (RFS) for males, presence of brain edema, younger patients (50 mm, tumor localization at intraventricular and anterior cranial base areas, WHO grade II/III meningiomas, and complex karyotypes; the latter 5 variables showed an independent predictive value in multivariate analysis. Based on these parameters, a prognostic score was established for each individual case, and patients were stratified into 4 risk categories with significantly different (P, This work was partially supported by grants from the Fundação para a Ciência e Tecnologia (PIC/IC/83108/2007, FCT, Portugal); Fondo de Investigaciones Sanitarias (FIS/FEDER 06/0312 and RETICC RD06/0020/0035, RD06/0020/0059 and RD12/0036/0048, Instituto de Salud Carlos III (ISCIII/FEDER), Ministerio de Sanidad y Consumo, Madrid, Spain), Caja Burgos (Spain), Fundación MMA (exp 75312010 and 87692011, Madrid, Spain), and Consejeria Sanidad Junta de Castilla y León, Gerencia Regional de Salud: GRS689/A/11. Patrícia Domingues is supported by grant (SFRH/BD/64799/2009) from FCT. Maria Dolores Tabernero is supported by IECSCYL (Fundación Instituto de Estudios Ciencias de la Salud de Castilla y León, Soria, Spain).

This is an open-access article distributed under the terms of the Creative Commons Attribution License., [Background]: Meningioma was the first solid tumor shown to contain a recurrent genetic alteration e.g. monosomy 22/del(22q), NF2 being the most relevant gene involved. Although monosomy 22/del(22q) is present in half of all meningiomas, and meningiomas frequently carry NF2 mutations, no study has been reported so far in which both alterations are simultaneously assessed and correlated with the features of the disease. [Methods]: Here, we analyzed the frequency of both copy number changes involving chromosome 22 and NF2 mutations in 20 sporadic meningiomas using high-density SNP-arrays, interphase-FISH and PCR techniques. [Results]: Our results show a significant frequency of NF2 mutations (6/20 patients, 30%), most of which (5/6) had not been previously reported in sporadic meningiomas. NF2 mutations involved five different exons and led to a truncated protein (p.Leu163CysfsX46, p.Phe62LeufsX61, p.Asp281MetfsX15, p.Phe285LeufsX11, p.Gln389ArgfsX37) and an in frame deletion of Phe119. Interestingly, all NF2 mutated cases were menopausal women with monosomy 22 but not del(22q). [Conclusions]: These results confirm and extend on previous observations about the high frequency and heterogeneity of NF2 mutations in sporadic meningiomas and indicate they could be restricted to a well-defined cytogenetic and clinical subgroup of menopausal women. Further studies in large series of patients are required to confirm our observations., This work has been partially supported by grants from Consejeria Sanidad Junta de Castilla y León, Gerencia Regional de Salud: GRS689/A/11. Fondo de Investigaciones Sanitarias, Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo, Madrid, Spain: RTICC RD06/0020/0035, RD06/0020/0059 and RD12/0036/0048. MD Tabernero is supported by IECSCYL (Fundación Instituto de Estudios Ciencias de la Salud de Castilla y León).

Despite recent advances in the identification of the cytogenetic profiles of meningiomas, a significant group of tumors still show normal karyotypes or few chromosomal changes. The authors analyzed the cytogenetic profile of 50 meningiomas using fluorescence in situ hybridization and high-density (500 K) single nucleotide polymorphism (SNP) arrays. Our results confirm that del(22q) (52%) and del(1p) (16%) (common deleted regions: 22q11.21-22q13.3. and 1p31.2-p36.33) are the most frequent alterations. Additionally, recurrent monosomy 14 (8%), del(6q) (10%), del(7p) (10%), and del(19q) (4%) were observed, while copy number patterns consistent with recurrent chromosomal gains, gene amplification, and copy number neutral loss of heterozygosity (cnLOH) were either absent or rare. Based on their overall SNP profiles, meningiomas could be classified into: (i) diploid cases, (ii) meningiomas with a single chromosomal change [e.g., monosomy 22/del(22q)] and (iii) tumors with ≥2 altered chromosomes. In summary, our results confirm and extend on previous observations showing that the most recurrent chromosomal abnormalities in meningiomas correspond to chromosome losses localized in chromosomes 1, 22 and less frequently in chromosomes 6, 7, 14, and 19, while chromosomal gains and cnLOH are restricted to a small proportion of cases. Finally, a set of cancer-associated candidate genes associated with the TP53, MYC, CASP3, HDAC1, and TERT signaling pathways was identified, in cases with coexisting monosomy 14 and del(1p). © 2012 Wiley Periodicals, Inc., Supported by: Consejería de Sanidad, Grant number: 66A/06; Consejería de Educación Junta de Castilla y León (Valladolid, Spain), Grant number: HUS 05A06; Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación-FEDER, Madrid, Spain (Fondo de Investigaciones Sanitarias), Grant numbers: FIS/ FEDER 06/0312, RTICC RD06/0020/0035, RD06/0020/0059; Fundación MM, Grant number: AP87692011; IECSCYL (Fundación Instituto de Estudios Ciencias de la Salud de Castilla y León).