Both baseline CTC number and change in CTC number after one cycle of chemotherapy are independent prognostic factors for SCLC. Molecular comparison of CTCs to cells in CTM may provide novel insights into SCLC biology.

CTCs are detectable in patients with stage IV NSCLC and are a novel prognostic factor for this disease. Further validation is warranted before routine clinical application.

Small-cell lung cancer (SCLC), an aggressive neuroendocrine tumor with early dissemination and dismal prognosis, accounts for 15-20% of lung cancer cases and ∼200,000 deaths each year. Most cases are inoperable, and biopsies to investigate SCLC biology are rarely obtainable. Circulating tumor cells (CTCs), which are prevalent in SCLC, present a readily accessible 'liquid biopsy'. Here we show that CTCs from patients with either chemosensitive or chemorefractory SCLC are tumorigenic in immune-compromised mice, and the resultant CTC-derived explants (CDXs) mirror the donor patient's response to platinum and etoposide chemotherapy. Genomic analysis of isolated CTCs revealed considerable similarity to the corresponding CDX. Most marked differences were observed between CDXs from patients with different clinical outcomes. These data demonstrate that CTC molecular analysis via serial blood sampling could facilitate delivery of personalized medicine for SCLC. CDXs are readily passaged, and these unique mouse models provide tractable systems for therapy testing and understanding drug resistance mechanisms.

Serological cell death biomarkers and circulating tumor cells (CTCs) have potential uses as tools for pharmacodynamic blood-based assays and their subsequent application to early clinical trials. In this study, we evaluated both the expression and clinical significance of CTCs and serological cell death biomarkers in patients with small cell lung cancer. Blood samples from 88 patients were assayed using enzyme-linked immunosorbent assays for various cytokeratin 18 products (eg, M65, cell death, M30, and apoptosis) as well as nucleosomal DNA. CTCs (per 7.5 ml of blood) were quantified using Veridex CellSearch technology. Before therapeutic treatment, cell death biomarkers were elevated in patients compared with controls. CTCs were detected in 86% of patients; additionally, CD56 was detectable in CTCs, confirming their neoplastic origin. M30 levels correlated with the percentage of apoptotic CTCs. M30 , M65 , lactate dehydrogenase , and CTC number were prognostic for patient survival as determined by univariate analysis. Using multivariate analysis , both lactate dehydrogenase and M65 levels remained significant. CTC number fell following chemotherapy , whereas levels of serological cell death biomarkers peaked at 48 hours and fell by day 22 , mirroring the tumor response. A 48-hour rise in nucleosomal DNA and M30 levels was associated with early response and severe toxicity , respectively. Our results provide a rationale to include the use of serological biomark- Small cell lung cancer (SCLC) is initially chemosensitive but invariably relapses with a chemoresistant phenotype.1 A number of molecularly targeted therapies have been evaluated attempting to improve outcome, but none have succeeded to date.2 Ideally, early clinical trials should incorporate validated pharmacodynamic biomarkers, conducted to good clinical laboratory practice, that demonstrate both proof of mechanism (drug hits target) and proof of concept (tumor responds to drug).3 Although possible, serial biopsies are rare in SCLC, and the tissue obtained often insufficient for extensive molecular profiling. Thus, there is a pressing need for blood-based biomarkers that report therapeutic response.Assays of drug-induced cell death are potential proof of concept biomarkers for multiple therapeutics. 4 The M30 Apoptosense and M65 assays (Peviva, Bromma, Sweden) detect cytokeratin (CK) 18, expressed in epithelial but not hematopoietic cells, and released into the blood following cytoskeletal disassembly and degradation during apoptotic and/or necrotic cell death. 5 The M30 antibody recognizes a caspase-cleaved neoepitope of CK18 that is only revealed during apoptosis, whereas the M65 assay detects full length and cleaved forms of CK18 reporting apoptosis and necrosis.6 Nucleosomal DNA (nDNA) results from cleavage of chromatin by apoptotic endonucleases into membrane bound DNA fragments that are phagocytosed by macrophages and sub-

Ceritinib, 450 mg with food, had similar exposure and a more favorable GI safety profile than ceritinib, 750 mg in fasted patients with ALK-positive NSCLC.

Somatic mutations in PIK3CA (encoding a class I phosphoinositide 3 kinase (PI3K) subunit) modulate PI3K signalling to influence tumour behaviour and occur in up to 40% of breast cancers. Inhibitors of PI3K signalling are entering clinical trials, but the impact of PIKC3A mutation on tumour response has yet to be clarified. This study investigated the potential utility of circulating free DNA (cfDNA) as a source for PIK3CA mutation detection in patients with breast cancer. cfDNA extracted (QIAamp Virus spin kit) from blood and matched archival tumour from 46 patients with metastatic breast cancer and 30 patients with localised, operable breast cancer was assessed for hotspot PIK3CA mutations using Amplification Refractory Mutation System (ARMS()) allele-specific PCR and Scorpion probes. PIK3CA mutations were detected in 13/46 (28%) plasma-derived and 10/46 (21%) serum-derived cfDNA samples from metastatic breast cancer patients. In 41 cases with matched tumour and plasma-derived cfDNA data, concordance (same mutation status in plasma and tumour) was 95%. Where a PIK3CA mutation was present in tumour, the 'pick up' in plasma-derived cfDNA was 80%. PIK3CA mutations were present in tumours from 14/30 (47%) localised breast cancers, but no PIK3CA mutations were detected in matched cfDNA. These data demonstrate feasibility and potential utility of cfDNA for PIK3CA mutation detection in patients with metastatic breast cancer. Studies are underway to qualify PIK3CA mutation in cfDNA as a predictive biomarker allowing patient stratification in clinical trials of mechanism-based therapeutics that target PI3K signalling pathways.

Purpose: AZD2014 is a novel, oral, m-TORC 1/2 inhibitor that has shown in vitro and in vivo efficacy across a range of preclinical human cancer models.Experimental Design: A rolling six-dose escalation was performed to define an MTD (part A), and at MTD a further cohort of patients was treated to further characterize toxicities and perform pre-and posttreatment biopsies (part B). AZD2014 was administered orally twice a day continuously. Flow cytometry, ELISA, and immunohistochemistry were used to quantify pharmacodynamic biomarkers. Pharmacokinetic analysis was carried out by mass spectrometry.Results: A total of 56 patients were treated across a dose range of 25 to 100 mg. The MTD was 50 mg twice daily. The dose-limiting toxicities were fatigue and mucositis. At the MTD, the most common adverse events (AE) were fatigue (78%), nausea (51%), and mucositis (49%), but these were equal to or greater than grade 3 in only 5% of patients. Drug levels achieved at the MTD (AUC ss 6686 ngÁh/mL, C max ss 1,664 ng/mL) were consistent with activity in preclinical models. A reduction in p-S6 levels and Ki67 staining was observed in 8 of 8 and 5 of 9 evaluable paired biopsy samples. Partial responses were seen in a patient with pancreatic cancer and a patient with breast cancer, who were found to have a PDGFR and ERBB2 mutation, respectively.Conclusions: The recommended phase II dose for further evaluation of AZD2014 is 50 mg twice daily, and at this dose it has been possible to demonstrate pharmacologically relevant plasma concentrations, target inhibition in tumor, and clinical responses.

Over recent years the role of biomarkers in anticancer drug development has expanded across a spectrum of applications ranging from research tool during early discovery to surrogate endpoint in the clinic. However, in Europe when biomarker measurements are performed on samples collected from subjects entered into clinical trials of new investigational agents, laboratories conducting these analyses become subject to the Clinical Trials Regulations. While these regulations are not specific in their requirements of research laboratories, quality assurance and in particular assay validation are essential. This review, therefore, focuses on a discussion of current thinking in biomarker assay validation. Five categories define the majority of biomarker assays from 'absolute quantitation' to 'categorical'. Validation must therefore take account of both the position of the biomarker in the spectrum towards clinical end point and the level of quantitation inherent in the methodology. Biomarker assay validation should be performed ideally in stages on 'a fit for purpose' basis avoiding unnecessarily dogmatic adherence to rigid guidelines but with careful monitoring of progress at the end of each stage. These principles are illustrated with two specific examples: (a) absolute quantitation of protein biomarkers by mass spectrometry and (b) the M30 and M65 ELISA assays as surrogate end points of cell death.