The molecular classification of glioblastoma (GBM) based on gene expression might better explain outcome and response to treatment than clinical factors. Whole transcriptome sequencing using ...next-generation sequencing platforms is rapidly becoming accepted as a tool for measuring gene expression for both research and clinical use. Fresh frozen (FF) tissue specimens of GBM are difficult to obtain since tumor tissue obtained at surgery is often scarce and necrotic and diagnosis is prioritized over freezing. After diagnosis, leftover tissue is usually stored as formalin-fixed paraffin-embedded (FFPE) tissue. However, RNA from FFPE tissues is usually degraded, which could hamper gene expression analysis. We compared RNA-Seq data obtained from matched pairs of FF and FFPE GBM specimens. Only three FFPE out of eleven FFPE-FF matched samples yielded informative results. Several quality-control measurements showed that RNA from FFPE samples was highly degraded but maintained transcriptomic similarities to RNA from FF samples. Certain issues regarding mutation analysis and subtype prediction were detected. Nevertheless, our results suggest that RNA-Seq of FFPE GBM specimens provides reliable gene expression data that can be used in molecular studies of GBM if the RNA is sufficiently preserved.
We here demonstrate that the anti-diabetic drug metformin interacts synergistically with the anti-HER2 monoclonal antibody trastuzumab (Tzb; Herceptin™) to eliminate stem/progenitor cell populations ...in HER2-gene-amplified breast carcinoma cells. When using the mammosphere culture technique, graded concentrations of single-agent metformin (range 50-1,000 μmol/l) were found to dose-dependently reduce the number of mammospheres formed by SKBR3 (a Tzb-naïve model), SKBR3 TzbR (a model of acquired auto-resistance to Tzb) and JIMT-1 (a model of refractoriness to Tzb and other HER2-targeted therapies ab initio) HER2-overexpressing breast cancer cells. Single-agent Tzb likewise reduced mammosphere-forming efficiency (MSFE) in Tzb-naïve SKBR3 cells, but it failed to significantly decrease MSFE in Tzb-resistant SKBR3 TzbR and JIMT-1 cells. Of note, CD44-overexpressing Tzb-refractory SKBR3 TzbR and JIMT-1 cells retained an exquisite sensitivity to single-agent metformin. Concurrent combination of metformin with Tzb synergistically reduced MSFE as well as the size of mammospheres in Tzb-refractory SKBR3 TzbR and JIMT-1 cells. Flow cytometry analyses confirmed that metformin and Tzb functioned synergistically to down-regulate the percentage of Tzb-refractory JIMT-1 cells displaying the CD44pos/CD24neg/low stem/progenitor immunophenotype. Given that MSFE and mammosphere size are indicators of stem self-renewal and progenitor cell proliferation, respectively, our current findings reveal for the first time that: (a) Tzb refractoriness in HER2 overexpressors can be explained in terms of Tzb-resistant/CD44-overexpressing/tumor-initiating stem cells; (b) metformin synergistically interacts with Tzb to suppress self-renewal and proliferation of cancer stem/progenitor cells in HER2-positive carcinomas.
Aim
To compare the effectiveness of alternating pressure air mattresses vs. overlays to prevent pressure ulcers in mechanically ventilated patients in intensive care units.
Background
Pressure ulcers ...prevention is an important issue in the nursing of critically ill patients. It is not clear whether alternating pressure air mattresses are more effective than overlays to prevent pressure ulcers.
Design
Prospective quasi‐experimental study.
Methods
A prospective quasi‐experimental study was conducted among patients in the medical–surgery intensive care unit of a university hospital on mechanical ventilation ≥24 hours during two time periods (2001 and 2006). Overlays were used in 2001 and mattresses in 2006. Primary outcome was the incidence of pressure ulcers grade ≥II (according to the European Pressure Ulcer Advisory Panel) during intensive care unit stay.
Results
The study included 221 patients (116 in 2001 and 105 in 2006). Baseline characteristics were similar between groups except for a higher Acute Physiology and Chronic Health Evaluation III score, total and first‐day respiratory Sequential Organ Failure Assessment Score on day 1 in overlay group. There was significantly lower incidence density in the mattress vs. overlay group (12·41 cases/1000 days vs. 18·67 cases/1000 days of stay). The multivariate analyses showed the use of the mattress to be a protective factor against pressure ulcer onset.
Conclusion
This quasi‐experiment study that alternative pressure air mattresses were more effective than alternating pressure air overlays in preventing pressure ulcers in mechanically ventilated critical care patients.
An unexplored molecular scenario that might explain the inhibitory impact of the anti-diabetic drug metformin on the genesis of breast cancer relates to metformin's ability to modulate the expression ...status of micro (mi)RNAs. We here report the first miRNA expression profiling of human epithelial breast cancer cells cultured in the presence of metformin. We conducted real-time transcription polymerase chain reaction (qRT-PCR) Arrays to quantitatively compare the expression profile of 88 cancer-related miRNA sequences before and after treatment of MCF-7 cells, which were used as well-differentiated, epithelioid cell controls, with graded concentrations of metformin. Metformin-treated MCF-7 cells notably exhibited up to 18-fold increases in miRNA lethal-7a (let-7a) expression compared with untreated control cells. We confirmed that MCF-7 cells undergoing epithelial-to-mesenchymal (EMT) transition in response to the cytokine TGFβ notably up-regulated (~5-fold) miRNA-181a expression and exhibited better mammosphere-forming capabilities. We then explored the ability of metformin to impede TGFβ-enhanced propensity of breast cancer stem cells to form mammospheres in a miRNA-181a-related manner. Remarkably, TGFβ treatment failed to up-regulate miRNA-181a expression in the presence of metformin, which was able to fully abrogate TGFβ-enhanced mammosphere-forming ability. In addition, metformin co-treatment fully prevented TGFβ-induced down-regulation of the tumor suppressor miRNA-96 (~10-fold). Metformin's molecular functioning to prevent invasive breast cancer can be explained in terms of its previously unrecognized ability to efficiently up-regulate the tumor-suppressive miRNAs let-7a & miRNA-96 and inhibit the oncogenic miRNA-181a, thus epigenetically preserving the differentiated phenotype of mammary epithelium while preventing EMT-related cancer-initiating cell self-renewal.
Metastatic breast cancer (MBC) diagnosis in young women negatively impacts on quality of life (QoL) and daily activities, disrupting their life project and forcing them to face new psychosocial ...challenges. The recently published results on the improvement of the overall survival of pre- or perimenopausal women with hormone-receptor-positive, HER2-negative MBC treated with CDK4/6 inhibitors plus endocrine therapy, while preserving, and in some items improving their QoL, will change the landscape of the management of this patient population. Their extended survival and potential improvement in QoL will, therefore, modify their specific needs in terms of psychosocial support.
The complexity of the care of young women with MBC is described herein, based on an extensive literature review. Further research about the specific psychosocial requirements of these women and a new multidisciplinary holistic approach is paramount to properly address their concerns and preferences. The communication with and support of their partners, parents and children is an important factor affecting the QoL of these patients. Altogether, a multidisciplinary care, open communication and personalized support is required to address the psychosocial implications of the new prognostic expectations on these patients with the incorporation of new targeted therapies.
•Life project disruption in young women with metastatic breast cancer.•Scarce research and lack of specific QoL questionnaires.•Multidisciplinary holistic approach key to address concerns of young MBC patients.•New therapies extend survival and improve quality of life of MBC patients.•Psychosocial support needs to be adapted to these new prognostic expectations.
Glioblastoma is the most aggressive brain tumor in adults and has few therapeutic options. The study of molecular subtype classifications may lead to improved prognostic classification and ...identification of new therapeutic targets. The Cancer Genome Atlas (TCGA) subtype classification has mainly been applied in U.S. clinical trials, while the intrinsic glioma subtype (IGS) has mainly been applied in European trials.
From paraffin-embedded tumor samples of 432 patients with uniformly treated, newly diagnosed glioblastoma, we built tissue microarrays for IHC analysis and applied RNA sequencing to the best samples to classify them according to TCGA and IGS subtypes.
We obtained transcriptomic results from 124 patients. There was a lack of agreement among the three TCGA classificatory algorithms employed, which was not solely attributable to intratumoral heterogeneity. There was overlapping of TCGA mesenchymal subtype with IGS cluster 23 and of TCGA classical subtype with IGS cluster 18. Molecular subtypes were not associated with prognosis, but levels of expression of 13 novel genes were identified as independent prognostic markers in glioma-CpG island methylator phenotype-negative patients, independently of clinical factors and
methylation. These findings were validated in at least one external database. Three of the 13 genes were selected for IHC validation. In particular, high
RNA expression and low ZNF7 protein expression were strongly associated with longer survival, independently of molecular subtypes.
TCGA and IGS molecular classifications of glioblastoma have no higher prognostic value than individual genes and should be refined before being applied to clinical trials.
We have tested the hypothesis that the antidiabetic biguanide metformin can be used to manipulate the threshold for stress-induced senescence (SIS), thus accelerating the onset of cancer-protective ...cellular senescence in response to oncogenic stimuli. Using senescence-prone murine embryonic fibroblasts (MEFs), we assessed whether metformin treatment modified the senescence phenotype that is activated in response to DNA damaging inducers. Metformin significantly enhanced the number of MEFs entering a senescent stage in response to doxorubicin, an anthracycline that induces cell senescence by activating DNA damage signaling pathways (e.g., ATM/ATR) in a reactive oxygen species (ROS)-dependent manner. Using WI-38 and BJ-1 human diploid fibroblasts (HDFs), we explored whether metformin supplementation throughout their entire replicative lifespan may promote the early appearance of the biomarkers of replicative senescence. Chronic metformin significantly reduced HDFs' lifespan by accelerating both the loss of replicative potential and the acquisition of replicative senescence-related biomarkers (e.g., enlarged and flattened cell shapes, loss of arrayed arrangement, accumulation of intracellular and extracellular debris and SA-β-gal-positive staining). Metformin functioned as a bona fide stressful agent, inducing monotonic, dose-dependent, SIS-like responses in BJ-1 HDFs, which are highly resistant to ROS-induced premature senescence. Metformin-induced SIS in BJ-1 fibroblasts was accompanied by the striking activation of several microRNAs belonging to the miR-200s family (miR-200a, miR-141 and miR429) and miR-205, thus mimicking a recently described ability of ROS to chemosensitize cancer cells by specifically upregulating anti-EMT (epithelial-to-mesenchymal transition) miR-200s. Because the unlimited proliferative potential of stem cells results from their metabolic refractoriness to SIS, we finally tested if metformin treatment could circumvent the stress (e.g., ROS)-resistant phenotype of induced pluripotent stem cells (iPSCs). Metformin treatment drastically reduced both the number and the size of iPSC colonies and notably diminished the staining of the pluripotency marker alkaline phosphatase. Our current findings, altogether, reveal for the first time that metformin can efficiently lower the threshold for SIS to generate an "stressed" cell phenotype that becomes pre-sensitized to oncogenic-like stimuli, including DNA damaging, proliferative and/or stemness inducers.
The biguanide metformin, a widely used drug for the treatment of type 2 diabetes, may exert cancer chemopreventive effects by suppressing the transformative and hyperproliferative processes that ...initiate carcinogenesis. Metformin's molecular targets in cancer cells (e.g., mTOR, HER2) are similar to those currently being used for directed cancer therapy. However, metformin is nontoxic and might be extremely useful for enhancing treatment efficacy of mechanism-based and biologically targeted drugs. Here, we first revisit the epidemiological, preclinical, and clinical evidence from the last 5 years showing that metformin is a promising candidate for oncology therapeutics. Second, the anticancer effects of metformin by both direct (insulin-independent) and indirect (insulin-dependent) mechanisms are discussed in terms of metformin-targeted processes and the ontogenesis of cancer stem cells (CSC), including Epithelial-to-Mesenchymal Transition (EMT) and microRNAs-regulated dedifferentiation of CSCs. Finally, we present preliminary evidence that metformin may regulate cellular senescence, an innate safeguard against cellular immortalization. There are two main lines of evidence that suggest that metformin's primary target is the immortalizing step during tumorigenesis. First, metformin activates intracellular DNA damage response checkpoints. Second, metformin attenuates the anti-senescence effects of the ATP-generating glycolytic metabotype-the Warburg effect-, which is required for self-renewal and proliferation of CSCs. If metformin therapy presents an intrinsic barrier against tumorigenesis by lowering the threshold for stress-induced senescence, metformin therapeutic strategies may be pivotal for therapeutic intervention for cancer. Current and future clinical trials will elucidate whether metformin has the potential to be used in preventive and treatment settings as an adjuvant to current cancer therapeutics.
Rindopepimut (also known as CDX-110), a vaccine targeting the EGFR deletion mutation EGFRvIII, consists of an EGFRvIII-specific peptide conjugated to keyhole limpet haemocyanin. In the ACT IV study, ...we aimed to assess whether or not the addition of rindopepimut to standard chemotherapy is able to improve survival in patients with EGFRvIII-positive glioblastoma.
In this randomised, double-blind, phase 3 trial, we recruited patients aged 18 years and older with glioblastoma from 165 hospitals in 22 countries. Eligible patients had newly diagnosed glioblastoma confirmed to express EGFRvIII by central analysis, and had undergone maximal surgical resection and completion of standard chemoradiation without progression. Patients were stratified by European Organisation for Research and Treatment of Cancer recursive partitioning analysis class, MGMT promoter methylation, and geographical region, and randomly assigned (1:1) with a prespecified randomisation sequence (block size of four) to receive rindopepimut (500 μg admixed with 150 μg GM-CSF) or control (100 μg keyhole limpet haemocyanin) via monthly intradermal injection until progression or intolerance, concurrent with standard oral temozolomide (150–200 mg/m2 for 5 of 28 days) for 6–12 cycles or longer. Patients, investigators, and the trial funder were masked to treatment allocation. The primary endpoint was overall survival in patients with minimal residual disease (MRD; enhancing tumour <2 cm2 post-chemoradiation by central review), analysed by modified intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01480479.
Between April 12, 2012, and Dec 15, 2014, 745 patients were enrolled (405 with MRD, 338 with significant residual disease SRD, and two unevaluable) and randomly assigned to rindopepimut and temozolomide (n=371) or control and temozolomide (n=374). The study was terminated for futility after a preplanned interim analysis. At final analysis, there was no significant difference in overall survival for patients with MRD: median overall survival was 20·1 months (95% CI 18·5–22·1) in the rindopepimut group versus 20·0 months (18·1–21·9) in the control group (HR 1·01, 95% CI 0·79–1·30; p=0·93). The most common grade 3–4 adverse events for all 369 treated patients in the rindopepimut group versus 372 treated patients in the control group were: thrombocytopenia (32 9% vs 23 6%), fatigue (six 2% vs 19 5%), brain oedema (eight 2% vs 11 3%), seizure (nine 2% vs eight 2%), and headache (six 2% vs ten 3%). Serious adverse events included seizure (18 5% vs 22 6%) and brain oedema (seven 2% vs 12 3%). 16 deaths in the study were caused by adverse events (nine 4% in the rindopepimut group and seven 3% in the control group), of which one—a pulmonary embolism in a 64-year-old male patient after 11 months of treatment—was assessed as potentially related to rindopepimut.
Rindopepimut did not increase survival in patients with newly diagnosed glioblastoma. Combination approaches potentially including rindopepimut might be required to show efficacy of immunotherapy in glioblastoma.
Celldex Therapeutics, Inc.
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