NTRK2 gene fusions are uncommon in pilocytic astrocytoma.

BACKGROUND: Pilocytic astrocytoma is the most frequent pediatric glioma. Despite its overall good prognosis, complete surgical resection is sometimes unfeasible, especially for patients with deep-seated tumors. For these patients, the identification of targetable genetic alterations such as NTRK fusions, raised as a new hope for therapy. The presence of gene fusions involving NTRK2 has been rarely reported in pilocytic astrocytoma. The aim of the present study was to investigate the frequency of NTRK2 alterations in a series of Brazilian pilocytic astrocytomas. METHODS: Sixty-nine pilocytic astrocytomas, previously characterized for BRAF and FGFR1 alterations were evaluated. The analysis of NTRK2 alterations was performed using a dual color break apart fluorescence in situ hybridization (FISH) assay. RESULTS: NTRK2 fusions were successfully evaluated by FISH in 62 of the 69 cases. Neither evidence of NTRK2 gene rearrangements nor NTRK2 copy number alterations were found. CONCLUSIONS: NTRK2 alterations are uncommon genetic events in pilocytic astrocytomas, regardless of patients' clinicopathological and molecular features.

Inter- and intra-tumor heterogeneity of SMAD4 loss in head and neck squamous cell carcinomas.

Reports regarding the frequency of SMAD4 loss in human head and neck squamous cell carcinoma (HNSCC) vary significantly. We have shown that SMAD4 deletion contributes to HNSCC initiation and progression. Therefore, accurately detecting genetic SMAD4 loss is critical to determine prognosis and therapeutic interventions in personalized medicine. We developed a SMAD4 fluorescence in situ hybridization (FISH) assay to identify chromosomal SMAD4 loss at the single cell level of primary HNSCC specimens and patient derived xenograft (PDX) tumors derived from HNSCCs. SMAD4 heterozygous loss was detected in 35% of primary HNSCCs and 41.3% of PDX tumors. Additionally, 4.3% of PDX tumors had SMAD4 homozygous loss. These frequencies of SMAD4 loss were similar to those in The Cancer Genome Atlas (TCGA). However, we identified significant heterogeneities of SMAD4 loss (partial or complete) among cells within each tumor. We also found that aneuploidy (monosomy and polysomy) contributed greatly to how to define chromosomal SMAD4 deletion. Furthermore, in cultured PDX tumors, SMAD4 mutant cells outcompeted SMAD4 wildtype cells, resulting in establishing homogenous SMAD4 mutant HNSCC cell lines with partial or complete genomic SMAD4 loss, suggesting a survival advantage of SMAD4 mutant cells. Taken together, our study reveals inter- and intra-tumor heterogeneities of SMAD4 chromosomal loss in HNSCCs. Further, SMAD4 FISH assay provides a platform for future clinical diagnosis of SMAD4 chromosomal loss that potentially serves as a molecular marker for prognosis and therapeutic intervention in cancer patients.

Cetuximab plus carboplatin and paclitaxel with or without bevacizumab versus carboplatin and paclitaxel with or without bevacizumab in advanced NSCLC (SWOG S0819): a randomised, phase 3 study.

BACKGROUND: EGFR antibodies have shown promise in patients with advanced non-small-cell lung cancer (NSCLC), particularly with squamous cell histology. We hypothesised that EGFR copy number by fluorescence in-situ hybridisation (FISH) can identify patients most likely to benefit from these drugs combined with chemotherapy and we aimed to explore the activity of cetuximab with chemotherapy in patients with advanced NSCLC who are EGFR FISH-positive. METHODS: We did this open-label, phase 3 study (SWOG S0819) at 277 sites in the USA and Mexico. We randomly assigned (1:1) eligible patients with treatment-naive stage IV NSCLC to receive paclitaxel (200 mg/m2; every 21 days) plus carboplatin (area under the curve of 6 by modified Calvert formula; every 21 days) or carboplatin plus paclitaxel and bevacizumab (15 mg/kg; every 21 days), either with cetuximab (250 mg/m2 weekly after loading dose; cetuximab group) or without (control group), stratified by bevacizumab treatment, smoking status, and M-substage using a dynamic-balancing algorithm. Co-primary endpoints were progression-free survival in patients with EGFR FISH-positive cancer and overall survival in the entire study population. We analysed clinical outcomes with the intention-to-treat principle and analysis of safety outcomes included patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov (number NCT00946712). FINDINGS: Between Aug 13, 2009, and May 30, 2014, we randomly assigned 1313 patients to the control group (n=657; 277 with bevacizumab and 380 without bevacizumab in the intention-to-treat population) or the cetuximab group (n=656; 283 with bevacizumab and 373 without bevacizumab in the intention-to-treat population). EGFR FISH was assessable in 976 patients and 400 patients (41%) were EGFR FISH-positive. The median follow-up for patients last known to be alive was 35·2 months (IQR 22·9-39·9). After 194 progression-free survival events in the cetuximab group and 198 in the control group in the EGFR FISH-positive subpopulation, progression-free survival did not differ between treatment groups (hazard ratio [HR] 0·92, 95% CI 0·75-1·12; p=0·40; median 5·4 months [95% CI 4·5-5·7] vs 4·8 months [3·9-5·5]). After 570 deaths in the cetuximab group and 593 in the control group, overall survival did not differ between the treatment groups in the entire study population (HR 0·93, 95% CI 0·83-1·04; p=0·22; median 10·9 months [95% CI 9·5-12·0] vs 9·2 months [8·7-10·3]). In the prespecified analysis of EGFR FISH-positive subpopulation with squamous cell histology, overall survival was significantly longer in the cetuximab group than in the control group (HR 0·58, 95% CI 0·36-0·86; p=0·0071), although progression-free survival did not differ between treatment groups in this subgroup (0·68, 0·46-1·01; p=0·055). Overall survival and progression-free survival did not differ among patients who were EGFR FISH non-positive with squamous cell histology (HR 1·04, 95% CI 0·78-1·40; p=0·77; and 1·02, 0·77-1·36; p=0·88 respectively) or patients with non-squamous histology regardless of EGFR FISH status (for EGFR FISH-positive 0·88, 0·68-1·14; p=0·34; and 0·99, 0·78-1·27; p=0·96; respectively; and for EGFR FISH non-positive 1·00, 0·85-1·17; p=0·97; and 1·03, 0·88-1·20; p=0·69; respectively). The most common grade 3-4 adverse events were decreased neutrophil count (210 [37%] in the cetuximab group vs 158 [25%] in the control group), decreased leucocyte count (103 [16%] vs 74 [20%]), fatigue (81 [13%] vs 74 [20%]), and acne or rash (52 [8%] vs one [<1%]). 59 (9%) patients in the cetuximab group and 31 (5%) patients in the control group had severe adverse events. Deaths related to treatment occurred in 32 (6%) patients in the cetuximab group and 13 (2%) patients in the control group. INTERPRETATION: Although this study did not meet its primary endpoints, prespecified subgroup analyses of patients with EGFR FISH-positive squamous-cell carcinoma cancers are encouraging and support continued evaluation of anti-EGFR antibodies in this subpopulation. FUNDING: National Cancer Institute and Eli Lilly and Company.

Authentication of M14 melanoma cell line proves misidentification of MDA-MB-435 breast cancer cell line.

A variety of analytical approaches have indicated that melanoma cell line UCLA-SO-M14 (M14) and breast carcinoma cell line MDA-MB-435 originate from a common donor. This indicates that at some point in the past, one of these cell lines became misidentified, meaning that it ceased to correspond to the reported donor and instead became falsely identified (through cross-contamination or other means) as a cell line from a different donor. Initial studies concluded that MDA-MB-435 was the misidentified cell line and M14 was the authentic cell line, although contradictory evidence has been published, resulting in further confusion. To address this question, we obtained early samples of the melanoma cell line (M14), a lymphoblastoid cell line from the same donor (ML14), and donor serum preserved at the originator's institution. M14 samples were cryopreserved in December 1975, before MDA-MB-435 cells were established in culture. Through a series of molecular characterizations, including short tandem repeat (STR) profiling and cytogenetic analysis, we demonstrated that later samples of M14 and MDA-MB-435 correspond to samples of M14 frozen in 1975, to the lymphoblastoid cell line ML14, and to the melanoma donor's STR profile, sex and blood type. This work demonstrates conclusively that M14 is the authentic cell line and MDA-MB-435 is misidentified. With clear provenance information and authentication testing of early samples, it is possible to resolve debates regarding the origins of problematic cell lines that are widely used in cancer research.

Assessment of biologically aggressive, recurrent glandular odontogenic cysts for mastermind-like 2 (MAML2) rearrangements: histopathologic and fluorescent in situ hybridization (FISH) findings in 11 cases.

BACKGROUND: Glandular odontogenic cyst (GOC) demonstrates a significant predilection toward localized biologic aggressiveness and recurrence. GOC shares certain histopathologic features with intraosseous mucoepidermoid carcinoma (IMEC). The current investigation evaluates a group of recurrent, biologically aggressive GOCs to determine whether any cases demonstrated unique histologic features or mastermind-like2 (MAML2) rearrangements common to IMEC. METHODS: Microscopic slides from 11 previously diagnosed GOCs were stained with hematoxylin and eosin and assessed by 2 study participants for 10 classic histopathologic features required to establish a diagnosis of GOC. Cases were evaluated utilizing break-apart fluorescent in situ hybridization (FISH) analysis for the presence of MAML2 gene rearrangements. Clinical and demographic data on all patients were recorded. RESULTS: The mean age for patients included in the study was 55.27 years with a range of 36 to 72 years. The most common presenting symptom was a jaw expansion, and all cysts presented initially as a unilocular or multilocular radiolucency. Cysts displayed a minimum of 6 of 10 histologic parameters necessary for a diagnosis of GOC. One case demonstrated MAML2 rearrangements by FISH. That case also showed marked ciliation of cyst-lining epithelial cells and extensive mucous-secreting goblet cell proliferation. CONCLUSION: Findings in the current study are in concert with previous investigations, and although this study finds only limited molecular evidence to support the premise that recurrent biologically aggressive GOCs are a precursor to IMEC, detection of MAML2 rearrangements in 1 case suggests that such a theoretic transition, while rare, is possible.

Crizotinib in ROS1-rearranged non-small-cell lung cancer.

BACKGROUND: Chromosomal rearrangements of the gene encoding ROS1 proto-oncogene receptor tyrosine kinase (ROS1) define a distinct molecular subgroup of non-small-cell lung cancers (NSCLCs) that may be susceptible to therapeutic ROS1 kinase inhibition. Crizotinib is a small-molecule tyrosine kinase inhibitor of anaplastic lymphoma kinase (ALK), ROS1, and another proto-oncogene receptor tyrosine kinase, MET. METHODS: We enrolled 50 patients with advanced NSCLC who tested positive for ROS1 rearrangement in an expansion cohort of the phase 1 study of crizotinib. Patients were treated with crizotinib at the standard oral dose of 250 mg twice daily and assessed for safety, pharmacokinetics, and response to therapy. ROS1 fusion partners were identified with the use of next-generation sequencing or reverse-transcriptase-polymerase-chain-reaction assays. RESULTS: The objective response rate was 72% (95% confidence interval [CI], 58 to 84), with 3 complete responses and 33 partial responses. The median duration of response was 17.6 months (95% CI, 14.5 to not reached). Median progression-free survival was 19.2 months (95% CI, 14.4 to not reached), with 25 patients (50%) still in follow-up for progression. Among 30 tumors that were tested, we identified 7 ROS1 fusion partners: 5 known and 2 novel partner genes. No correlation was observed between the type of ROS1 rearrangement and the clinical response to crizotinib. The safety profile of crizotinib was similar to that seen in patients with ALK-rearranged NSCLC. CONCLUSIONS: In this study, crizotinib showed marked antitumor activity in patients with advanced ROS1-rearranged NSCLC. ROS1 rearrangement defines a second molecular subgroup of NSCLC for which crizotinib is highly active. (Funded by Pfizer and others; ClinicalTrials.gov number, NCT00585195.).

De novo generation of adipocytes from circulating progenitor cells in mouse and human adipose tissue.

White adipocytes in adults are typically derived from tissue resident mesenchymal progenitors. The recent identification of de novo production of adipocytes from bone marrow progenitor-derived cells in mice challenges this paradigm and indicates an alternative lineage specification that adipocytes exist. We hypothesized that alternative lineage specification of white adipocytes is also present in human adipose tissue. Bone marrow from transgenic mice in which luciferase expression is governed by the adipocyte-restricted adiponectin gene promoter was adoptively transferred to wild-type recipient mice. Light emission was quantitated in recipients by in vivo imaging and direct enzyme assay. Adipocytes were also obtained from human recipients of hematopoietic stem cell transplantation. DNA was isolated, and microsatellite polymorphisms were exploited to quantify donor/recipient chimerism. Luciferase emission was detected from major fat depots of transplanted mice. No light emission was observed from intestines, liver, or lungs. Up to 35% of adipocytes in humans were generated from donor marrow cells in the absence of cell fusion. Nontransplanted mice and stromal-vascular fraction samples were used as negative and positive controls for the mouse and human experiments, respectively. This study provides evidence for a nontissue resident origin of an adipocyte subpopulation in both mice and humans.

A NOTCH1 gene copy number gain is a prognostic indicator of worse survival and a predictive biomarker to a Notch1 targeting antibody in colorectal cancer.

Dysregulation of the Notch1 receptor has been shown to facilitate the development and progression of colorectal cancer (CRC) and has been identified as an independent predictor of disease progression and worse survival. Although mutations in the NOTCH1 receptor have not been described in CRC, we have previously discovered a NOTCH1 gene copy number gain in a portion of CRC tumor samples. Here, we demonstrated that a NOTCH1 gene copy number gain is significantly associated with worse survival and a high percentage of gene duplication in a cohort of patients with advanced CRC. In our CRC patient-derived tumor xenograft (PDTX) model, tumors harboring a NOTCH1 gain exhibited significant elevation of the Notch1 receptor, JAG1 ligand and cleaved Notch1 activity. In addition, a significant association was identified between a gain in NOTCH1 gene copy number and sensitivity to a Notch1-targeting antibody. These findings suggest that patients with metastatic CRC that harbor a gain in NOTCH1 gene copy number have worse survival and that targeting this patient population with a Notch1 antibody may yield improved outcomes.

Clinicopathologic features and outcomes of patients with lung adenocarcinomas harboring BRAF mutations in the Lung Cancer Mutation Consortium.

BACKGROUND: The advent of effective targeted therapy for BRAF(V600E) -mutant lung adenocarcinomas necessitates further exploration of the unique clinical features and behavior of advanced-stage BRAF-mutant lung adenocarcinomas. METHODS: Data were reviewed for patients with advanced lung adenocarcinomas enrolled in the Lung Cancer Mutation Consortium whose tumors underwent testing for mutations in epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), human epidermal growth factor receptor 2 (HER2), AKT1, BRAF, dual-specificity mitogen-activated protein kinase kinase 1 (MEK1), neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA); for anaplastic lymphoma kinase (ALK) translocations; and for MET amplification. RESULTS: Twenty-one BRAF mutations were identified in 951 patients with adenocarcinomas (2.2%; 95% confidence interval [CI], 1.4%-3.4%): 17 (81%; 95% CI, 60%-92%) were BRAF(V600E) mutations, and 4 were non-BRAF(V600E) mutations. Among the 733 cases tested for all 10 genes, BRAF mutations were more likely to occur than most other genotypic abnormalities in current or former smokers (BRAF vs sensitizing EGFR, 82% vs 36%, mid-P < .001; BRAF vs ALK, 39%, mid-P = .003; BRAF vs other mutations, 49%, mid-P = .02; BRAF vs patients with more than 1 oncogenic driver [doubleton], 46%, mid-P = .04.) The double-mutation rate was 16% among patients with BRAF mutations but 5% among patients with other genomic abnormalities (mid-P = .045). Differences were not found in survival between patients with BRAF mutations and those with other genomic abnormalities (P > .20). CONCLUSIONS: BRAF mutations occurred in 2.2% of advanced-stage lung adenocarcinomas, were most commonly V600E, and were associated with distinct clinicopathologic features in comparison with other genomic subtypes and with a high mutation rate in more than 1 gene. These findings underscore the importance of comprehensive genomic profiling in assessing patients with advanced lung adenocarcinomas.

Multi-genetic events collaboratively contribute to Pten-null leukaemia stem-cell formation.

Cancer stem cells, which share many common properties and regulatory machineries with normal stem cells, have recently been proposed to be responsible for tumorigenesis and to contribute to cancer resistance. The main challenges in cancer biology are to identify cancer stem cells and to define the molecular events required for transforming normal cells to cancer stem cells. Here we show that Pten deletion in mouse haematopoietic stem cells leads to a myeloproliferative disorder, followed by acute T-lymphoblastic leukaemia (T-ALL). Self-renewable leukaemia stem cells (LSCs) are enriched in the c-Kit(mid)CD3(+)Lin(-) compartment, where unphosphorylated beta-catenin is significantly increased. Conditional ablation of one allele of the beta-catenin gene substantially decreases the incidence and delays the occurrence of T-ALL caused by Pten loss, indicating that activation of the beta-catenin pathway may contribute to the formation or expansion of the LSC population. Moreover, a recurring chromosomal translocation, T(14;15), results in aberrant overexpression of the c-myc oncogene in c-Kit(mid)CD3(+)Lin(-) LSCs and CD3(+) leukaemic blasts, recapitulating a subset of human T-ALL. No alterations in Notch1 signalling are detected in this model, suggesting that Pten inactivation and c-myc overexpression may substitute functionally for Notch1 abnormalities, leading to T-ALL development. Our study indicates that multiple genetic or molecular alterations contribute cooperatively to LSC transformation.

Suppression of leukemia development caused by PTEN loss.

Multiple genetic or molecular alterations are known to be associated with cancer stem cell formation and cancer development. Targeting such alterations, therefore, may lead to cancer prevention. By crossing our previously established phosphatase and tensin homolog (Pten)-null acute T-lymphoblastic leukemia (T-ALL) model onto the recombination-activating gene 1(-/-) background, we show that the lack of variable, diversity and joining [V(D)J] recombination completely abolishes the Tcrα/δ-c-myc translocation and T-ALL development, regardless of ß-catenin activation. We identify mammalian target of rapamycin (mTOR) as a regulator of ß-selection. Rapamycin, an mTOR-specific inhibitor, alters nutrient sensing and blocks T-cell differentiation from CD4(-)CD8(-) to CD4(+)CD8(+), the stage where the Tcrα/δ-c-myc translocation occurs. Long-term rapamycin treatment of preleukemic Pten-null mice prevents Tcrα/δ-c-myc translocation and leukemia stem cell (LSC) formation, and it halts T-ALL development. However, rapamycin alone fails to inhibit mTOR signaling in the c-Kit(mid)CD3(+)Lin(-) population enriched for LSCs and eliminate these cells. Our results support the idea that preventing LSC formation and selectively targeting LSCs are promising approaches for antileukemia therapies.

Using multiplexed assays of oncogenic drivers in lung cancers to select targeted drugs.

IMPORTANCE: Targeting oncogenic drivers (genomic alterations critical to cancer development and maintenance) has transformed the care of patients with lung adenocarcinomas. The Lung Cancer Mutation Consortium was formed to perform multiplexed assays testing adenocarcinomas of the lung for drivers in 10 genes to enable clinicians to select targeted treatments and enroll patients into clinical trials. OBJECTIVES: To determine the frequency of oncogenic drivers in patients with lung adenocarcinomas and to use the data to select treatments targeting the identified driver(s) and measure survival. DESIGN, SETTING, AND PARTICIPANTS: From 2009 through 2012, 14 sites in the United States enrolled patients with metastatic lung adenocarcinomas and a performance status of 0 through 2 and tested their tumors for 10 drivers. Information was collected on patients, therapies, and survival. INTERVENTIONS: Tumors were tested for 10 oncogenic drivers, and results were used to select matched targeted therapies. MAIN OUTCOMES AND MEASURES: Determination of the frequency of oncogenic drivers, the proportion of patients treated with genotype-directed therapy, and survival. RESULTS: From 2009 through 2012, tumors from 1007 patients were tested for at least 1 gene and 733 for 10 genes (patients with full genotyping). An oncogenic driver was found in 466 of 733 patients (64%). Among these 733 tumors, 182 tumors (25%) had the KRAS driver; sensitizing EGFR, 122 (17%); ALK rearrangements, 57 (8%); other EGFR, 29 (4%); 2 or more genes, 24 (3%); ERBB2 (formerly HER2), 19 (3%); BRAF, 16 (2%); PIK3CA, 6 (<1%); MET amplification, 5 (<1%); NRAS, 5 (<1%); MEK1, 1 (<1%); AKT1, 0. Results were used to select a targeted therapy or trial in 275 of 1007 patients (28%). The median survival was 3.5 years (interquartile range [IQR], 1.96-7.70) for the 260 patients with an oncogenic driver and genotype-directed therapy compared with 2.4 years (IQR, 0.88-6.20) for the 318 patients with any oncogenic driver(s) who did not receive genotype-directed therapy (propensity score-adjusted hazard ratio, 0.69 [95% CI, 0.53-0.9], P = .006). CONCLUSIONS AND RELEVANCE: Actionable drivers were detected in 64% of lung adenocarcinomas. Multiplexed testing aided physicians in selecting therapies. Although individuals with drivers receiving a matched targeted agent lived longer, randomized trials are required to determine if targeting therapy based on oncogenic drivers improves survival. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01014286.

Diagnostic assays for identification of anaplastic lymphoma kinase-positive non-small cell lung cancer.

In series dominated by adenocarcinoma histology, approximately 5% of non-small cell lung cancers (NSCLCs) harbor an anaplastic lymphoma kinase (ALK) gene rearrangement. Crizotinib, a tyrosine kinase inhibitor with significant activity against ALK, has demonstrated high response rates and prolonged progression-free survival in ALK-positive patients enrolled in phase 1/2 clinical trials. In 2011, crizotinib received accelerated approval from the US Food and Drug Administration (FDA) for the treatment of proven ALK-positive NSCLC using an FDA-approved diagnostic test. Currently, only break-apart fluorescence in situ hybridization testing is FDA approved as a companion diagnostic for crizotinib; however, many other assays are available or in development. In the current review, the authors summarize the diagnostic tests available, or likely to become available, that could be used to identify patients with ALK-positive NSCLC, highlighting the pros and cons of each.

Native and rearranged ALK copy number and rearranged cell count in non-small cell lung cancer: implications for ALK inhibitor therapy.

BACKGROUND: Patients with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) respond to ALK inhibitors. Clinically, the presence of ≥15% cells with rearrangements identified on break-apart fluorescence in situ hybridization (FISH) classifies tumors as positive. Increases in native and rearranged ALK copy number also occur. METHODS: In total, 1426 NSCLC clinical specimens (174 ALK-positive specimens and 1252 ALK-negative specimens) and 24 ALK-negative NSCLC cell lines were investigated. ALK copy number and genomic status were assessed by FISH. RESULTS: Clinical specimens with 0% to 9%, 10% to 15%, 16% to 30%, 31% to 50%, and >50% ALK-positive cells were identified in 79.3%, 8.5%, 1.4%, 2.7%, and 8.1%, respectively. An increased native ALK copy number (≥3 copies per cell in ≥40% of cells) was detected in 19% of ALK-positive tumors and in 62% of ALK-negative tumors. In ALK-negative tumors, abundant, focal amplification of native ALK was rare (0.8%). Other atypical patterns occurred in approximately 6% of tumors. The mean native ALK copy number ranged from 2.1 to 6.9 copies in cell lines and was not correlated with crizotinib sensitivity (50% inhibitory concentration, 0.34-2.8 µM; r = 0.279; P = .1764). Neither native or rearranged ALK copy number nor the percentage of positive cells correlated with extra-central nervous system progression-free survival in ALK-positive patients who were receiving crizotinib. CONCLUSIONS: Overall, 8.5% of tumors fell below the established positivity threshold by ≤5%. Further investigation of ALK by other diagnostic techniques in such cases may be warranted. Native ALK copy number increases alone were not associated with sensitivity to ALK inhibition in vitro. However, rare, complex patterns of increased native ALK in patients should be studied further; because, otherwise, atypical rearrangements contained within these may be missed.

Anaplastic lymphoma kinase inhibition in non-small-cell lung cancer.

BACKGROUND: Oncogenic fusion genes consisting of EML4 and anaplastic lymphoma kinase (ALK) are present in a subgroup of non-small-cell lung cancers, representing 2 to 7% of such tumors. We explored the therapeutic efficacy of inhibiting ALK in such tumors in an early-phase clinical trial of crizotinib (PF-02341066), an orally available small-molecule inhibitor of the ALK tyrosine kinase. METHODS: After screening tumor samples from approximately 1500 patients with non-small-cell lung cancer for the presence of ALK rearrangements, we identified 82 patients with advanced ALK-positive disease who were eligible for the clinical trial. Most of the patients had received previous treatment. These patients were enrolled in an expanded cohort study instituted after phase 1 dose escalation had established a recommended crizotinib dose of 250 mg twice daily in 28-day cycles. Patients were assessed for adverse events and response to therapy. RESULTS: Patients with ALK rearrangements tended to be younger than those without the rearrangements, and most of the patients had little or no exposure to tobacco and had adenocarcinomas. At a mean treatment duration of 6.4 months, the overall response rate was 57% (47 of 82 patients, with 46 confirmed partial responses and 1 confirmed complete response); 27 patients (33%) had stable disease. A total of 63 of 82 patients (77%) were continuing to receive crizotinib at the time of data cutoff, and the estimated probability of 6-month progression-free survival was 72%, with no median for the study reached. The drug resulted in grade 1 or 2 (mild) gastrointestinal side effects. CONCLUSIONS: The inhibition of ALK in lung tumors with the ALK rearrangement resulted in tumor shrinkage or stable disease in most patients. (Funded by Pfizer and others; ClinicalTrials.gov number, NCT00585195.).

Genetic stability of bone marrow-derived human mesenchymal stromal cells in the Quantum System.

BACKGROUND AIMS: The Quantum® Cell Expansion System (Quantum; Terumo BCT, Inc, Lakewood, CO, USA) is a novel hollow fiber-based device that automates and closes the cell culture process, reducing labor intensive tasks such as manual cell culture feeding and harvesting. The manual cell selection and expansion processes for the production of clinical-scale quantities of bone marrow-derived human mesenchymal stromal cells (BM-hMSCs) have been successfully translated onto the Quantum platform previously. The formerly static, manual, in vitro process performed primarily on tissue culture polystyrene substrates may raise the question of whether BM-hMSCs cultured on a hollow fiber platform yields comparable cell quality. METHODS: A rigorous battery of assays was used to determine the genetic stability of BM-hMSCs selected and produced with the Quantum. In this study, genetic stability was determined by assessing spectral karyotype, micronucleus formation and tumorigenicity to resolve chromosomal aberrations in the stem cell population. Cell phenotype, adherent growth kinetics and tri-lineage differentiation were also evaluated. HMSC bone marrow aspirates, obtained from three approved donors, were expanded in parallel using T225 culture flasks and the Quantum. RESULTS: BM-hMSCs harvested from the Quantum demonstrated immunophenotype, morphology and tri-lineage differentiation capacity characteristics consistent with the International Society of Cell Therapy standard for hMSCs. Cell populations showed no malignant neoplastic formation in athymic mice 60 days post-transplant, no clonal chromosomal aberrations were observed and no DNA damage was found as measured by micronucleus formation. CONCLUSIONS: Quantum-produced BM-hMSCs are of comparable quality and demonstrate analogous genetic stability to BM-hMSCs cultured on tissue culture polystyrene substrates.

De novo generation of white adipocytes from the myeloid lineage via mesenchymal intermediates is age, adipose depot, and gender specific.

It is generally assumed that white adipocytes arise from resident adipose tissue mesenchymal progenitor cells. We challenge this paradigm by defining a hematopoietic origin for both the de novo development of a subset of white adipocytes in adults and a previously uncharacterized adipose tissue resident mesenchymal progenitor population. Lineage and cytogenetic analysis revealed that bone marrow progenitor (BMP)-derived adipocytes and adipocyte progenitors arise from hematopoietic cells via the myeloid lineage in the absence of cell fusion. Global gene expression analysis indicated that the BMP-derived fat cells are bona fide adipocytes but differ from conventional white or brown adipocytes in decreased expression of genes involved in mitochondrial biogenesis and lipid oxidation, and increased inflammatory gene expression. The BMP-derived adipocytes accumulate with age, occur in higher numbers in visceral than in subcutaneous fat, and in female versus male mice. BMP-derived adipocytes may, therefore, account in part for adipose depot heterogeneity and detrimental changes in adipose metabolism and inflammation with aging and adiposity.

Activity and safety of crizotinib in patients with ALK-positive non-small-cell lung cancer: updated results from a phase 1 study.

BACKGROUND: ALK fusion genes occur in a subset of non-small-cell lung cancers (NSCLCs). We assessed the tolerability and activity of crizotinib in patients with NSCLC who were prospectively identified to have an ALK fusion within the first-in-man phase 1 crizotinib study. METHODS: In this phase 1 study, patients with ALK-positive stage III or IV NSCLC received oral crizotinib 250 mg twice daily in 28-day cycles. Endpoints included tumour responses, duration of response, time to tumour response, progression-free survival (PFS), overall survival at 6 and 12 months, and determination of the safety and tolerability and characterisation of the plasma pharmacokinetic profile of crizotinib after oral administration. Responses were analysed in evaluable patients and PFS and safety were analysed in all patients. This study is registered with ClinicalTrials.gov, number NCT00585195. FINDINGS: Between Aug 27, 2008, and June 1, 2011, 149 ALK-positive patients were enrolled, 143 of whom were included in the response-evaluable population. 87 of 143 patients had an objective response (60·8%, 95% CI 52·3-68·9), including three complete responses and 84 partial responses. Median time to first documented objective response was 7·9 weeks (range 2·1-39·6) and median duration of response was 49·1 weeks (95% CI 39·3-75·4). The response rate seemed to be largely independent of age, sex, performance status, or line of treatment. Median PFS was 9·7 months (95% CI 7·7-12·8). Median overall survival data are not yet mature, but estimated overall survival at 6 and 12 months was 87·9% (95% CI 81·3-92·3) and 74·8% (66·4-81·5), respectively. 39 patients continued to receive crizotinib for more than 2 weeks after progression because of perceived ongoing clinical benefit from the drug (12 for at least 6 months from the time of their initial investigator-defined disease progression). Overall, 144 (97%) of 149 patients experienced treatment-related adverse events, which were mostly grade 1 or 2. The most common adverse events were visual effects, nausea, diarrhoea, constipation, vomiting, and peripheral oedema. The most common treatment-related grade 3 or 4 adverse events were neutropenia (n=9), raised alanine aminotransferase (n=6), hypophosphataemia (n=6), and lymphopenia (n=6). INTERPRETATION: Crizotinib is well tolerated with rapid, durable responses in patients with ALK-positive NSCLC. There seems to be potential for ongoing benefit after initial disease progression in this population, but a more formal definition of ongoing benefit in this context is needed.

PDGFRA, KIT, and KDR Gene Amplification in Glioblastoma: Heterogeneity and Clinical Significance.

Glioblastoma (GBM) is the most frequent tumor of the central nervous system, and its heterogeneity is a challenge in treatment. This study examined tumoral heterogeneity involving PDGFRA, KIT, and KDR gene amplification (GA) in 4q12 and its association with clinical parameters. Specimens from 22 GBM cases with GA for the 4q12 amplicon detected by FISH were investigated for homogeneous or heterogeneous coamplification patterns, diffuse or focal distribution of cells harboring GA throughout tumor sections, and pattern of clustering of fluorescence signals. Sixteen cases had homogenously amplification for all three genes (45.5%), for PDGFRA and KDR (22.7%), or only for PDGFRA (4.6%); six cases had heterogeneous GA patterns, with subpopulations including GA for all three genes and for two genes - PDGFRA and KDR (13.6%), or GA for all three and for only one gene - PDGFRA (9.1%) or KIT (4.6%). In 6 tumors (27.3%), GA was observed in focal tumor areas, while in the remaining 16 tumors (72.7%) it was diffusely distributed throughout the pathological specimen. Amplification was universally expressed as double minutes and homogenously stained regions. Coamplification of all three genes PDGFRA, KIT, and KDR, age ≥ 60 years, and total tumor resection were statistically associated with poor prognosis. FISH proved effective for detailed interpretation of molecular heterogeneity. The study uncovered an even more diverse range of amplification patterns involving the 4q12 oncogenes in GBM than previously described, thus highlighting a complex tumoral heterogeneity to be considered when devising more effective therapies.

Prevalence, molecular markers, and outcome of bronchial squamous carcinoma in situ in high-risk subjects.

Bronchial squamous carcinoma in situ (CIS) is a preinvasive lesion that is thought to precede invasive carcinoma. We conducted prospective autofluorescence and white light bronchoscopy trials between 1992 and 2016 to assess the prevalence, molecular markers, and outcome of individuals with CIS and other preneoplastic bronchial lesions. Biopsies were evaluated at multiple levels and selected biopsies were tested for aneuploidy and DNA sequenced for TP53 mutation. Thirty-one individuals with CIS were identified. Twenty-two cases of CIS occurred in association with concurrent invasive carcinomas. Seven of the invasive tumors were radiographically occult. In two cases, CIS spread from the focus of invasive carcinoma into contralateral lung lobes, forming secondary invasive tumors. In nine cases, CIS occurred as isolated lesions and one progressed to invasive squamous carcinoma at the same site 40 months after discovery. In a second case, CIS was a precursor of carcinoma at a separate site in a different lobe. In seven cases CIS regressed to a lower grade or disappeared. High level chromosomal aneusomy was often associated with TP53 mutation and with invasive carcinoma. CIS most often occurs in association with invasive squamous carcinoma and may extend along the airways into distant lobes. In rare cases, CIS may be observed to directly transform into invasive carcinoma. CIS may be indicative of invasive tumor at a separate distant site. Isolated CIS may regress. Molecular changes parallel histological changes in CIS and may be used to map clonal expansion in the airways.