Atypical teratoid/rhabdoid tumor (AT/RT) is the most common malignant CNS tumor of children below 6 months of age. The majority of AT/RTs demonstrate genomic alterations in SMARCB1 (INI1, SNF5, BAF47) or, to a lesser extent, SMARCA4 (BRG1) of the SWItch/sucrose nonfermentable chromatin remodeling complex. Recent transcription and methylation profiling studies suggest the existence of molecular subgroups. Thus, at the root of these seemingly enigmatic tumors lies a network of factors related to epigenetic regulation, which is not yet completely understood. While conventional-type chemotherapy may have significant survival benefit for certain patients, it remains to be determined which patients will eventually prove resistant to chemotherapy and thus need novel therapeutic strategies. Elucidation of the molecular consequences of a disturbed epigenome has led to the identification of a series of transduction cascades, which may be targeted for therapy. Among these are the pathways of cyclin D1/cyclin-dependent kinases 4 and 6, Hedgehog/GLI1, Wnt/ss-catenin, enhancer of zeste homolog 2, and aurora kinase A, among others. Compounds specifically targeting these pathways or agents that alter the epigenetic state of the cell are currently being evaluated in preclinical settings and in experimental clinical trials for AT/RT.
We evaluated the diagnostic value of static and dynamic O-(2-[F-18]fluoroethyl)-l-tyrosine (F-18-FET) PET parameters in patients with progressive or recurrent glioma. We retrospectively analyzed 132 dynamic F-18-FET PET and conventional MRI scans of 124 glioma patients (primary World Health Organization grade II, n = 55; grade III, n = 19; grade IV, n = 50; mean age, 52 +/- 14 y). Patients had been referred for PET assessment with clinical signs and/or MRI findings suggestive of tumor progression or recurrence based on Response Assessment in Neuro-Oncology criteria. Maximum and mean tumor/brain ratios of F-18-FET uptake were determined (20-40 min post-injection) as well as tracer uptake kinetics (ie, time to peak and patterns of the time-activity curves). Diagnoses were confirmed histologically (95%) or by clinical follow-up (5%). Diagnostic accuracies of PET and MR parameters for the detection of tumor progression or recurrence were evaluated by receiver operating characteristic analyses/chi-square test. Tumor progression or recurrence could be diagnosed in 121 of 132 cases (92%). MRI and F-18-FET PET findings were concordant in 84% and discordant in 16%. Compared with the diagnostic accuracy of conventional MRI to diagnose tumor progression or recurrence (85%), a higher accuracy (93%) was achieved by F-18-FET PET when a mean tumor/brain ratio a parts per thousand yen2.0 or time to peak < 45 min was present (sensitivity, 93%; specificity, 100%; accuracy, 93%; positive predictive value, 100%; P < .001). Static and dynamic F-18-FET PET parameters differentiate progressive or recurrent glioma from treatment-related nonneoplastic changes with higher accuracy than conventional MRI.
An accurate, nonsurgical diagnostic test for brain tumors is currently unavailable, and the methods of monitoring disease progression are not fully reliable. MicroRNA profiling of biological fluids has recently emerged as a diagnostic tool for several pathologic conditions. Here we tested whether microRNA profiling of cerebrospinal fluid (CSF) enables detection of glioblastoma, discrimination between glioblastoma and metastatic brain tumors, and reflects disease activity. We determined CSF levels of several cancer-associated microRNAs for 118 patients diagnosed with different types of brain cancers and nonneoplastic neuropathologies by quantitative reverse transcription PCR analysis. The levels of miR-10b and miR-21 are found significantly increased in the CSF of patients with glioblastoma and brain metastasis of breast and lung cancer, compared with tumors in remission and a variety of nonneoplastic conditions. Members of the miR-200 family are highly elevated in the CSF of patients with brain metastases but not with any other pathologic conditions, allowing discrimination between glioblastoma and metastatic brain tumors. Quantification of as few as 7 microRNAs in CSF enables differential recognition of glioblastoma and metastatic brain cancer using computational machine learning tools (Support Vector Machine) with high accuracy (91%-99%) on a test set of samples. Furthermore, we show that disease activity and treatment response can be monitored by longitudinal microRNA profiles in the CSF of glioblastoma and non small cell lung carcinoma patients. This study demonstrates that microRNA-based detection of brain malignancies can be reliably performed and that microRNAs in CSF can serve as biomarkers of treatment response in brain cancers.
The objective of this phase II single-arm study was to evaluate the efficacy and safety of pazopanib, a multi-targeted tyrosine kinase inhibitor, against vascular endothelial growth factor receptor (VEGFR)-1, -2, and -3, platelet-derived growth factor receptor-alpha and -beta, and c-Kit, in recurrent glioblastoma. Patients with = 6 months (PFS6 = 3%). Thirty patients (86%) had died and median survival was 35 weeks (95% CI: 24-47 weeks). Pazopanib was reasonably well tolerated with a spectrum of toxicities similar to other anti-VEGF/VEGFR agents. Single-agent pazopanib did not prolong PFS in this patient population but showed in situ biological activity as demonstrated by radiographic responses. ClinicalTrials.gov identifier: NCT00459381.
This randomized, open-label, active-controlled, dose-finding phase fib study evaluated the efficacy and safety of trabedersen (AP 12009) administered intratumorally by convection-enhanced delivery compared with standard chemotherapy in patients with recurrent/refractory high-grade glioma. One hundred and forty-five patients with central reference histopathology of recurrent/refractory glioblastoma multiforme (GBM) or anaplastic astrocytoma (AA) were randomly assigned to receive trabedersen at doses of 10 or 80 mu M or standard chemotherapy (temozolomide or procarbazine/lomustine/ vincristine). Primary endpoint was 6-month tumor control rate, and secondary endpoints included response at further timepoints, survival, and safety. Six-month tumor control rates were not significantly different in the entire study population (AA and GBM). Prespecified AA subgroup analysis showed a significant benefit regarding the 14-month tumor control rate for 10 mu M trabedersen vs chemotherapy (p=.0032). The 2-year survival rate had a trend for superiority for 10 mu M trabedersen vs chemotherapy (p=.10). Median survival for 10 mu M trabedersen was 39.1 months compared with 35.2 months for 80 mu M trabedersen and 21.7 months for chemotherapy (not significant). In GBM patients, response and survival results were comparable among the 3 arms. Exploratory analysis on GBM patients aged 80% at baseline indicated a 3-fold survival at 2 and 3 years for 10 mu M trabedersen vs chemotherapy. The frequency of patients with related or possibly drug-related adverse events was higher with standard chemotherapy (64%) than with 80 mu M trabedersen (43%) and 10 mu M trabedersen (27%). Superior efficacy and safety for 10 mu M trabedersen over 80 mu M trabedersen and chemotherapy and positive risk-benefit assessment suggest it as the optimal dose for further clinical development in high-grade glioma.
The clinical management/understanding of brain metastases (BM) has changed substantially in the last 5 years, with key advances and clinical trials highlighted in this review. Several of these changes stem from improvements in systemic therapy, which have led to better systemic control and longer overall patient survival, associated with increased time at risk for developing BM. Development of systemic therapies capable of preventing BM and controlling both intracranial and extracranial disease once BM are diagnosed is paramount. The increase in use of stereotactic radiosurgery alone for many patients with multiple BM is an outgrowth of the desire to employ treatments focused on local control while minimizing cognitive effects associated with whole brain radiotherapy. Complications from BM and their treatment must be considered in comprehensive patient management, especially with greater awareness that the majority of patients do not die from their BM. Being aware of significant heterogeneity in prognosis and therapeutic options for patients with BM is crucial for appropriate management, with greater attention to developing individual patient treatment plans based on predicted outcomes; in this context, recent prognostic models of survival have been extensively revised to incorporate molecular markers unique to different primary cancers.
Only a subset of patients with newly diagnosed glioblastoma (GBM) exhibit a response to standard therapy. To date, a biomarker panel with predictive power to distinguish treatment sensitive from treatment refractory GBM tumors does not exist. An analysis was performed using GBM microarray data from 4 independent data sets. An examination of the genes consistently associated with patient outcome, revealed a consensus 38-gene survival set. Worse outcome was associated with increased expression of genes associated with mesenchymal differentiation and angiogenesis. Application to formalin fixed-paraffin embedded (FFPE) samples using real-time reverse-transcriptase polymerase chain reaction assays resulted in a 9-gene subset which appeared robust in these samples. This 9-gene set was then validated in an additional independent sample set. Multivariate analysis confirmed that the 9-gene set was an independent predictor of outcome after adjusting for clinical factors and methylation of the methyl-guanine methyltransferase promoter. The 9-gene profile was also positively associated with markers of glioma stem-like cells, including CD133 and nestin. In sum, a multigene predictor of outcome in glioblastoma was identified which appears applicable to routinely processed FFPE samples. The profile has potential clinical application both for optimization of therapy in GBM and for the identification of novel therapies targeting tumors refractory to standard therapy.
Extent of resection (EOR) still remains controversial in therapy of glioblastoma multiforme (GBM). However, an increasing number of studies favor maximum EOR as being associated with longer patient survival. One hundred thirty-five GBM patients underwent tumor resection aided by 1.5T intraoperative MRI (iMRI) and integrated multimodal navigation. Tumor volume was quantified by manual segmentation. The influences of EOR, patient age, recurrent tumor, tumor localization, and gender on survival time were examined. Intraoperative MRI detected residual tumor volume in 88 patients. In 19 patients surgery was continued; further resection resulted in final gross total resection (GTR) for 9 patients (GTR increased from 47 [34.80%] to 56 [41.49%] patients). Tumor volumes were significantly reduced from 34.25 ± 23.68% (first iMRI) to 1.22 ± 16.24% (final iMRI). According to Kaplan-Meier estimates, median survival was 14 months (95% confidence interval [CI]: 11.7-16.2) for EOR ≥98% and 9 months (95% CI: 7.4-10.5) for EOR <98% (P< .0001); it was 9 months (95% CI: 7.3-10.7) for patients ≥65 years and 12 months (95% CI: 8.4-15.6) for patients <65 years (P < .05). Multivariate analysis showed a hazard ratio of 0.39 (95% CI: 0.24-0.63; P = .001) for EOR ≥98% and 0.61 (95% CI: 0.38-0.97; P < .05) for patient age <65 years. To our knowledge, this is the largest study including correlation of iMRI, tumor volumetry, and survival time. We demonstrate that navigation guidance and iMRI significantly contribute to optimal EOR with low postoperative morbidity, where EOR ≥98% and patient age <65 years are associated with significant survival advantages. Thus, maximum EOR should be the surgical goal in GBM surgery while preserving neurological function.
The purpose of the trial was to determine the survival and incidence of secondary tumors in children with medulloblastoma receiving radiotherapy plus chemotherapy. Three hundred seventy-nine eligible patients with nondisseminated medulloblastoma between the ages of 3 and 21 years were treated with 2340 cGy of craniospinal and 5580 cGy of posterior fossa irradiation. Patients were randomized between postradiation cisplatin and vincristine plus either CCNU or cyclophosphamide. Survival, pattern of relapse, and occurrence of secondary tumors were assessed. Five- and 10-year event-free survivals were 81 +/- 2% and 75.8 +/- 2.3%; overall survivals were 87 +/- 1.8% and 81.3 +/- 2.1%. Event-free survival was not impacted by chemotherapeutic regimen, sex, race, age at diagnosis, or gender. Seven patients had disease relapse beyond 5 years after diagnosis; relapse was local in 4 patients, local plus supratentorial in 2, and supratentorial alone in 1. Fifteen patients experienced secondary tumors as a first event at a median time of 5.8 years after diagnosis (11 >5 y postdiagnosis). All non-CNS solid secondary tumors (4) occurred in regions that had received radiation. Of the 6 high-grade gliomas, 5 occurred >5 years postdiagnosis. The estimated cumulative 10-year incidence rate of secondary malignancies was 4.2% (1.9%-6.5%). Few patients with medulloblastoma will relapse >= 5 years postdiagnosis; relapse will occur predominantly at the primary tumor site. Patients are at risk for development of secondary tumors, many of which are malignant gliomas. This may become an increasing issue as more children survive.
Leptomeningeal metastases (LM) currently lack standardization with respect to response assessment. A Response Assessment in Neuro-Oncology (RANO) working group with expertise in LM developed a consensus proposal for evaluating patients treated for this disease. Three basic elements in assessing response in LM are proposed: a standardized neurological examination, cerebral spinal fluid (CSF) cytology or flow cytometry, and radiographic evaluation. The group recommends that all patients enrolling in clinical trials undergo CSF analysis (cytology in all cancers; flow cytometry in hematologic cancers), complete contrast-enhanced neuraxis MRI, and in instances of planned intra-CSF therapy, radioisotope CSF flow studies. In conjunction with the RANO Neurological Assessment working group, a standardized instrument was created for assessing the neurological exam in patients with LM. Considering that most lesions in LM are nonmeasurable and that assessment of neuroimaging in LM is subjective, neuroimaging is graded as stable, progressive, or improved using a novel radiological LM response scorecard. Radiographic disease progression in isolation (ie, negative CSF cytology/flow cytometry and stable neurological assessment) would be defined as LM disease progression. The RANO LM working group has proposed a method of response evaluation for patients with LM that will require further testing, validation, and likely refinement with use.
Differentiating treatment-induced necrosis from tumor recurrence is a central challenge in neuro-oncology. These 2 very different outcomes after brain tumor treatment often appear similarly on routine follow-up imaging studies. They may even manifest with similar clinical symptoms, further confounding an already difficult process for physicians attempting to characterize a new contrast-enhancing lesion appearing on a patients follow-up imaging. Distinguishing treatment necrosis from tumor recurrence is crucial for diagnosis and treatment planning, and therefore, much effort has been put forth to develop noninvasive methods to differentiate between these disparate outcomes. In this article, we review the latest developments and key findings from research studies exploring the efficacy of structural and functional imaging modalities for differentiating treatment necrosis from tumor recurrence. We discuss the possibility of computational approaches to investigate the usefulness of fine-grained imaging characteristics that are difficult to observe through visual inspection of images. We also propose a flexible treatment-planning algorithm that incorporates advanced functional imaging techniques when indicated by the patients routine follow-up images and clinical condition.
To assess the accumulation of myeloid-derived suppressor cells (MDSCs) in the peripheral blood of patients with glioma and to define their heterogeneity and their immunosuppressive function. Peripheral blood mononuclear cells (PBMCs) from healthy control subjects and from patients with newly diagnosed glioma were stimulated with anti-CD3/anti-CD28 and T cells assessed for intracellular expression of interferon (IFN)-γ. Antibody staining of PBMCs from glioma patients and healthy donors (CD33, HLADR, CD15, and CD14) followed by 4-color flow cytometry analysis-defined MDSC levels in the peripheral blood. To assess the role of MDSCs in suppressing T cell IFNγ production, PBMCs were depleted of MDSCs using anti-CD33 and anti-CD15 antibody-coated beads prior to T cell stimulation. Enzyme-linked immunosorbent assays were used to assess plasma arginase activity and the level of granulocyte colony-stimulating factor (G-CSF). Patients with glioblastoma have increased MDSC counts (CD33+HLADR−) in their blood that are composed of neutrophilic (CD15+; >60%), lineage-negative (CD15−CD14−; 31%), and monocytic (CD14+; 6%) subsets. After stimulation, T cells from patients with glioblastoma had suppressed IFN-γ production when compared with healthy, age-matched donor T cells. Removal of MDSCs from the PBMCs with anti-CD33/CD15-coated beads significantly restored T cell function. Significant increases in arginase activity and G-CSF levels were observed in plasma specimens obtained from patients with glioblastoma. The accumulation of MDSCs in peripheral blood in patients with glioma likely promotes T cell immune suppression that is observed in this patient population. Increased plasma levels of arginase and G-CSF may relate to MDSC suppressor function and MDSC expansion, respectively, in patients with glioma.
Epidermal growth factor receptor variant III (EGFRvIII) is a tumor-specific mutation widely expressed in glioblastoma multiforme (GBM) and other neoplasms, but absent from normal tissues. Immunotherapeutic targeting of EGFRvIII could eliminate neoplastic cells more precisely but may be inhibited by concurrent myelosuppressive chemotherapy like temozolomide (TMZ), which produces a survival benefit in GBM. A phase II, multicenter trial was undertaken to assess the immunogenicity of an experimental EGFRvIII-targeted peptide vaccine in patients with GBM undergoing treatment with serial cycles of standard-dose (STD) (200 mg/m2 per 5 days) or dose-intensified (DI) TMZ (100 mg/m2 per 21 days). All patients receiving STD TMZ exhibited at least a transient grade 2 lymphopenia, whereas those receiving DI TMZ exhibited a sustained grade 3 lymphopenia (<500 cells/μL). CD3+ T-cell (P = .005) and B-cell (P = .004) counts were reduced significantly only in the DI cohort. Patients in the DI cohort had an increase in the proportion of immunosuppressive regulatory T cells (T Reg; P = .008). EGFRvIII-specific immune responses developed in all patients treated with either regimen, but the DI TMZ regimen produced humoral (P = .037) and delayed-type hypersensitivity responses (P = .036) of greater magnitude. EGFRvIII-expressing tumor cells were also eradicated in nearly all patients (91.6%; CI95: 64.0%-99.8%; P < .0001). The median progression-free survival (15.2 months; CI95: 11.0-18.5 months; hazard ratio [HR] = 0.35; P = .024) and overall survival (23.6 months; CI95: 18.5-33.1 months; HR = 0.23; P = .019) exceeded those of historical controls matched for entry criteria and adjusted for known prognostic factors. EGFRvIII-targeted vaccination induces patient immune responses despite therapeutic TMZ-induced lymphopenia and eliminates EGFRvIII-expressing tumor cells without autoimmunity.
To determine whether temozolomide is an active agent in the treatment of children with high-grade astrocytomas and whether survival is influenced by the expression of the O6-methylguanine-methyltransferase gene (MGMT) in these patients. In the Children's Oncology Group study ACNS0126, 107 patients with a diagnosis of anaplastic astrocytoma (AA), glioblastoma multiforme (GBM), or gliosarcoma were enrolled. All patients underwent concomitant chemoradiotherapy with temozolomide, followed by adjuvant chemotherapy with temozolomide. The outcomes were compared with those of children treated in Children's Cancer Group (CCG) study CCG-945. Formalin-fixed, paraffin-embedded tumor tissue was available in 71 cases for immunohistochemical analysis of MGMT expression. Ninety patients were deemed eligible, 31 with AA, 55 with GBM, and 4 with other eligible diagnoses. The 3-year event-free survival (EFS) and overall survival (OS) rates were 11 ± 3% and 22 ± 5%, respectively. There was no evidence that temozolomide given during radiation therapy and as adjuvant therapy resulted in improved EFS compared with that found in CCG-945 (p = 0.98). The 3-year EFS rate for AA was 13 ± 6% in ACNS0126 compared with 22 ± 5.5% in CCG-945 (p = 0.95). The 3-year EFS rate for GBM was 7 ± 4% in ACNS0126 compared with 15 ± 5% in CCG-945 (p = 0.77). The 2-year EFS rate was 17 ± 5% among patients without MGMT overexpression and 5 ± 4% among those with MGMT overexpression (p = 0.045). Temozolomide failed to improve outcome in children with high-grade astrocytomas. MGMT overexpression was adversely associated with survival.
A small subset of patients with nonsmall cell lung cancer (NSCLC) harbors mutations in the epidermal growth factor receptor (EGFR) that predict unique sensitivity to EGFR tyrosine kinase inhibitors (TKIs). The characteristics and behavior of brain metastases (BMs) in these patients have not been well described. The longitudinal records of all NSCLC patients who underwent EGFR mutation screening at our center from August 2004 to November 2008 were reviewed for eligibility, and 93 patients were identified who developed BM during the course of their disease. Survival was estimated using the Kaplan-Meier method and the log-rank test. Multivariable predictors were assessed via the Cox proportional hazards model. Among the 93 patients with BM, 41 (44%) had mutations in EGFR, including 13 exon 19 deletions and 12 L858R mutations. Eighty-three percent of patients with BM were treated initially with whole brain radiation, either alone (53%) or in combination with craniotomy for neurosurgical resection (22%) or stereotactic radiosurgery (8%). Median survival from the time of BM was 11.7 months and was longer for patients with an EGFR mutation (14.5 vs 7.6 months, P = .09). On multivariable analysis, EGFR mutation (HR: 0.50, 95% CI: 0.30-0.82), age (HR: 1.03, 95% CI: 1.00-1.05), and active extracranial disease (HR: 3.30, 95% CI: 1.70-6.41) were independently associated with survival. In NSCLC patients with BM, EGFR mutation status is associated with improved survival, independent of age, functional status, extracranial disease status, and number of BMs.
Brain metastases are associated with significant morbidity and mortality. Population-level data describing the incidence and prognosis of patients with brain metastases are lacking. The aim of this study was to characterize the incidence and prognosis of patients with brain metastases at diagnosis of systemic malignancy using recently released data from the Surveillance, Epidemiology, and End Results (SEER) program. We identified 1302166 patients with diagnoses of nonhematologic malignancies originating outside of the CNS between 2010 and 2013 and described the incidence proportion and survival of patients with brain metastases. We identified 26430 patients with brain metastases at diagnosis of cancer. Patients with small cell and non-small cell lung cancer displayed the highest rates of identified brain metastases at diagnosis; among patients presenting with metastatic disease, patients with melanoma (28.2%), lung adenocarcinoma (26.8%), non-small cell lung cancer not otherwise specified/other lung cancer (25.6%), small cell lung cancer (23.5%), squamous cell carcinoma of the lung (15.9%), bronchioloalveolar carcinoma (15.5%), and renal cancer (10.8%) had an incidence proportion of identified brain metastases of > 10%. Patients with brain metastases secondary to prostate cancer, bronchioloalveolar carcinoma, and breast cancer displayed the longest median survival (12.0, 10.0, and 10.0 months, respectively). In this study we provide generalizable estimates of the incidence and prognosis for patients with brain metastases at diagnosis of a systemic malignancy. These data may allow for appropriate utilization of brain-directed imaging as screening for subpopulations with cancer and have implications for clinical trial design and counseling of patients regarding prognosis.
Vascular endothelial growth factor (VEGF) is a critical regulator of angiogenesis. Inhibiting the VEGFVEGF receptor (R) signal transduction pathway in glioblastoma has recently been shown to delay progression, but the relative benefit and mechanisms of response and failure of anti-VEGF therapy and VEGFR inhibitors are not well understood. The purpose of our study was to evaluate the relative effectiveness of VEGF sequestration and/or VEGFR inhibition on orthotopic tumor growth and the mechanism(s) of treatment resistance. We evaluated, not only, the effects of anti-VEGF therapy (bevacizumab), anti-VEGFR therapy (sunitinib), and the combination on the survival of mice bearing orthotopic gliomas, but also the differential effects of the treatments on tumor vascularity, cellular proliferation, mesenchymal and stem cell markers, and myeloid cell infiltration using flow cytometry and immunohistochemistry. Bevacizumab significantly prolonged survival compared with the control or sunitinib alone. Both antiangiogenic agents initially reduced infiltration of macrophages and tumor vascularity. However, multitargeted VEGFR inhibition, but not VEGF sequestration, rapidly created a vascular gradient and more rapidly induced tumor hypoxia. Re-infiltration of macrophages was associated with the induction of hypoxia. Combination treatment with bevacizumab and sunitinib improved animal survival compared with bevacizumab therapy alone. However, at the time of tumor progression, a significant increase in CD11b/Gr1 granulocyte infiltration was observed, and tumors developed aggressive mesenchymal features and increased stem cell marker expression. Collectively, our results demonstrate a more prolonged decrease in tumor vascularity with bevacizumab than with sunitinib, associated with a delay in the development of hypoxia and sustained reduction of infiltrated myeloid cells.
Background. Glioma is one of the most aggressive and lethal human brain tumors. Accumulating evidence shows that microRNAs play important roles in cancers, including glioma. Previous studies reported that miR-124 levels were downregulated in glioma specimens. Here, we further investigate the potential role of miR-124 in glioma. Methods. The expression levels of miR-124 were detected in glioma specimens by quantitative reverse transcriptase PCR. The direct targets of miR-124 were identified by bioinformatics analysis and were further validated by immunoblotting and luciferase reporter assay. The effects of miR-124 on glioma cell proliferation and chemosensitivity to temozolomide were analyzed by Cell-Counting Kit 8 assay. Apoptosis was evaluated by fluorescence activated cell sorting analysis. A xenograft model was used to study the effect of miR-124 on tumor growth and angiogenesis. Results. Expression levels of miR-124 were greatly downregulated in glioma specimens. related Ras viral oncogene homolog (R-Ras) and neuroblastoma Ras viral oncogene homolog (N-Ras) were identified as direct targets of miR-124. MiR-124 inhibited glioma cell growth, invasion, angiogenesis, and tumor growth and increased chemosensitivity to temozolomide treatment by negatively regulating the Ras family and its downstream signaling pathways: phosphatidylinositol-3 kinase/Akt and Raf/extracellular signal-regulated kinase 1/2. Furthermore, overexpression of R-Ras rescued the inhibitory effects of miR-124. Meanwhile, overexpression of R-Ras and N-Ras restored miR-124-inhibited vascular endothelial growth factor (VEGF) transcription activation. In clinical glioma specimens, protein levels of R-Ras and N-Ras were upregulated and inversely correlated with miR-124 expression levels. Conclusions. Taken together, these results revealed that miR-124 levels in tumor tissues are associated with glioma occurrence, angiogenesis, and chemoresistance and that miR-124 may be used as a new diagnostic marker and therapeutic target for glioma in the future.
Background. Breast cancer brain metastases (BCBM) are challenging complications that respond poorly to systemic therapy. The role of the blood-tumor barrier in limiting BCBM drug delivery and efficacy has been debated. Herein, we determined tissue and serum levels of capecitabine, its prodrug metabolites, and lapatinib in women with BCBM resected via medically indicated craniotomy. Methods. Study patients with BCBM requiring surgical resection received either single-dose capecitabine (1250 mg/m(2)) 2-3 h before surgery or 2-5 doses of lapatinib (1250 mg) daily, the last dose 2-3 h before surgery. Serum samples were collected serially on the day of surgery. Drug concentrations were determined in serum and BCBM using liquid chromatography tandem mass spectrometry. Results. Twelve patients were enrolled: 8 for capecitabine and 4 for lapatinib. Measurable drug levels of capecitabine and metabolites, 5'-deoxy-5-fluorocytidine, 5'-deoxy-5-fluorouridine, and 5-fluorouracil, were detected in all BCBM. The ratio of BCBM to serum was higher for 5-fluorouracil than for capecitabine. As for lapatinib, the median BCBM concentrations ranged from 1.0 to 6.5 mM. A high variability (0.19-9.8) was noted for lapatinib BCBM-to-serum ratio. Conclusions. This is the first study to demonstrate that capecitabine and lapatinib penetrate to a significant though variable degree in human BCBM. Drug delivery to BCBM is variable and in many cases appears partially limiting. Elucidating mechanisms that limit drug concentration and innovative approaches to overcome limited drug uptake will be important to improve clinical efficacy of these agents in the central nervous system. Trial registration ID: NCT00795678.
Background. To examine the efficacy of valproic acid (VPA) given either with or without levetiracetam (LEV) on seizure control and on survival in patients with glioblastoma multiforme (GBM) treated with chemoradiation. Methods. A retrospective analysis was performed on 291 patients with GBM. The efficacies of VPA and LEV alone and as polytherapy were analyzed in 181 (62%) patients with seizures with a minimum follow-up of 6 months. Cox-regression survival analysis was performed on 165 patients receiving chemoradiation with temozolomide of whom 108 receiving this in combination with VPA for at least 3 months. Results. Monotherapy with either VPA or LEV was instituted in 137/143 (95.8%) and in 59/86 (68.6%) on VPA/LEV polytherapy as the next regimen. Initial freedom from seizure was achieved in 41/100 (41%) on VPA, in 16/37 (43.3%) on LEV, and in 89/116 (76.7%) on subsequent VPA/LEV polytherapy. At the end of follow-up, seizure freedom was achieved in 77.8% (28/36) on VPA alone, in 25/36 (69.5%) on LEV alone, and in 38/63 (60.3%) on VPA/LEV polytherapy with ongoing seizures on mono-therapy. Patients using VPA in combination with temozolomide showed a longer median survival of 69 weeks (95% confidence interval [CI]: 61.7-67.3) compared with 61 weeks (95% CI: 52.5-69.5) in the group without VPA (hazard ratio, 0.63; 95% CI: 0.43-0.92; P = .016), adjusting for age, extent of resection, and O-6-DNA methylguanine-methyltransferase promoter methylation status. Conclusions. Polytherapy with VPA and LEV more strongly contributes to seizure control than does either as monotherapy. Use of VPA together with chemoradiation with temozolomide results in a 2-months' longer survival of patients with GBM.
