ΔNp73 antisense activates PUMA and induces apoptosis in neuroblastoma cells

The p73 gene codes for various different protein isoforms. They include proteins expressed under the control of the P1 promoter that contain a transactivation domain and are similar in function to p53 (TAp73 isoforms), as well as proteins regulated by the P2 promoter that lack this domain and function as dominant negative inhibitors of TAp73 and p53 (ΔNp73 isoforms). Whereas TAp73 functions as a tumor suppressor with pro-apoptotic function, ΔNp73 is likely to prevent the induction of apoptosis in tumor cells and to participate in oncogenesis. Here we used a loss-of-function strategy to assess the role of ΔNp73 in SH-SY5Y neuroblastoma cells. An antisense oligonucleotide designed to target ΔNp73 mRNA, but not TAp73, was used to effectively downregulate this transcript. ΔNp73 downregulation was accompanied by increased levels of the pro-apoptotic BH3 family member PUMA at the mRNA and protein level, and by conformational activation of BAX which translocated to mitochondria. These ΔNp73 antisense-mediated alterations led to the induction of apoptosis as detected by decreased cell viability, augmented DNA fragmentation and increased caspase-3 activity in cell lysates. Our results demonstrate the cytoprotective role of ΔNp73 in neuroblastoma and suggest its use as a target for molecular intervention therap

Searching for targets for the systemic therapy of mesothelioma.

Malignant mesothelioma is an incurable disease associated with asbestos exposure arising in the pleural cavity and less frequently in the peritoneal cavity. Platinum-based combination chemotherapy with pemetrexed is the established standard of care. Multimodality approaches including surgery and radiotherapy are being investigated. Increasing knowledge about the molecular characteristics of mesothelioma had led to the identification of novel potential targets for systemic therapy. Current evidence suggests pathways activated in response to merlin deficiency, including Pi3K/mTOR and the focal adhesion kinase, as well as immunotherapeutic approaches to be most promising. This review elaborates on the rationale behind targeted approaches that have been and are undergoing exploration in mesothelioma and summarizes available clinical results and ongoing efforts to improve the systemic therapy of mesothelioma

Computer-Based Intensity Measurement Assists Pathologists in Scoring Phosphatase and Tensin Homolog Immunohistochemistry - Clinical Associations in NSCLC Patients of the European Thoracic Oncology Platform Lungscape Cohort.

Phosphatase and tensin homolog (PTEN) loss is frequently observed in NSCLC and associated with both phosphoinositide 3-kinase activation and tumoral immunosuppression. PTEN immunohistochemistry is a valuable readout, but lacks standardized staining protocol and cutoff value. After an external quality assessment using SP218, 138G6 and 6H2.1 anti-PTEN antibodies, scored on webbook and tissue microarray, the European Thoracic Oncology Platform cohort samples (n = 2245 NSCLC patients, 8980 tissue microarray cores) were stained with SP218. All cores were H-scored by pathologists and by computerized pixel-based intensity measurements calibrated by pathologists. All three antibodies differentiated six PTEN+ versus six PTEN- cases on external quality assessment. For 138G6 and SP218, high sensitivity and specificity was found for all H-score threshold values including prospectively defined 0, calculated 8 (pathologists), and calculated 5 (computer). High concordance among pathologists in setting computer-based intensities and between pathologists and computer in H-scoring was observed. Because of over-integration of the human eye, pixel-based computer H-scores were overall 54% lower. For all cutoff values, PTEN- was associated with smoking history, squamous cell histology, and higher tumor stage (p < 0.001). In adenocarcinomas, PTEN- was associated with poor survival. Calibration of immunoreactivity intensities by pathologists following computerized H-score measurements has the potential to improve reproducibility and homogeneity of biomarker detection regarding epitope validation in multicenter studies

A randomized open-label phase III trial evaluating the addition of denosumab to standard first-line treatment in advanced NSCLC : the European Thoracic Oncology Platform (ETOP) and European Organisation for Research and Treatment of Cancer (EORTC) SPLENDOUR trial

Introduction Receptor activator of NF-kB ligand stimulates NF-kB–dependent cell signaling and acts as the primary signal for bone resorption. Retrospective analysis of a large trial comparing denosumab versus zoledronic acid in bone metastatic solid tumors suggested significant overall survival (OS) advantage for patients with lung cancer with denosumab (p = 0.01). The randomized open-label phase III SPLENDOUR trial was designed to evaluate whether the addition of denosumab to standard first-line platinum-based doublet chemotherapy improved OS in advanced NSCLC. Methods Patients with stage IV NSCLC were randomized in a 1:1 ratio to either chemotherapy with or without denosumab (120 mg every 3–4 wks), stratified by the presence of bone metastases (at diagnosis), Eastern Cooperative Oncology Group performance status, histology, and region. To detect an OS increase from 9 to 11.25 months (hazard ratio [HR] = 0.80), 847 OS events were required. The trial closed prematurely owing to decreasing accrual rate. Results A total of 514 patients were randomized, with 509 receiving one or more doses of the assigned treatment (chemotherapy: 252, chemotherapy-denosumab: 257). The median age was 66.1 years, 71% were men, and 59% were former smokers. Bone metastases were identified in 275 patients (53%). Median OS (95% confidence interval [CI]) was 8.7 (7.6–11.0) months in the control arm versus 8.2 (7.5–10.4) months in the chemotherapy-denosumab arm (HR = 0.96; 95% CI: 0.78–1.19; one-sided p = 0.36). For patients with bone metastasis, HR was 1.02 (95% CI: 0.77–1.35), whereas for those without, HR was 0.90 (95% CI: 0.66–1.23). Adverse events grade 3 or greater were observed in 40.9%, 5.2%, 8.7% versus 45.5%, 10.9%, 10.5% of patients. Conditional power for OS benefit was less than or equal to 10%. Conclusions Denosumab was well-tolerated without unexpected safety concerns. There was no OS improvement for denosumab when added to chemotherapy in the intention-to-treat population and the subgroups with and without bone metastases. Our data do not provide evidence of a clinical benefit for denosumab in patients with NSCLC without bone metastases

Lung Cancer

Lung cancer treatment strategy relies on an accurate staging of the disease and a careful evaluation of patient characteristics, including capability of undergoing and tolerating a defined treatment plan. Therefore, a solid knowledge on all intervention-related adverse events and drug toxicities is essential for a reliable decision-making process. Most lung cancer patients are diagnosed at an advanced stage of the disease, correlated with a dismal prognosis. Systemic therapy is the mainstay, and drug selection still strongly relies on expected toxicity profile. This chapter first describes the drug standard options and their respective toxicities in this context. Side effects of more complex multimodality combined treatments of early non-small-cell lung cancer as well as small-cell lung cancer, usually involving use of the same cytotoxic agents jointly with surgery and radiotherapy, are discussed in the second part of this chapter