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Abstract 4954 Background: Standard chemotherapy with R-CHOP has a cure rate of approximately 60% for diffuse large B-cell lymphoma (DLBCL). Salvage therapy followed by autologous stem cell transplantation can cure 40–50% of patients. For patients who relapse following high dose therapy, salvage regimens are incurable. Combination therapy with rituximab, gemcitabine, vinorelbine, and liposomal doxorubicin (R-GND) has been shown to be efficacious in the setting of Hodgkin Lymphoma. We present the results of R-GND therapy among pts with relapsed refractory DLBCL. Methods: Patients treated with R-GND at Vanderbilt University Medical Center for DLBCL from January 2004 through December 2010 with R-GND regimen are presented. Clinical outcomes studied included response to therapy, overall mortality, and drug toxicities, in particular grade 3/4, including neutropenia, anemia, and opportunistic infection. Wilcoxon rank sum, chi square analysis, and Kaplan-Meier analysis were performed using SPSS-19 software. Results: Twenty one pts with relapsed large cell lymphoma following immuno-chemotherapy were treated with R-GND therapy. The median age of pts was 60.5 (range 24–81). Eleven pts were male. The cell of origin of DLBCL based on pathology was available on 13 patients. Ten were germinal center histogenic origin and 3 patients had DLBCL of non-germinal center origin. The median number of prior therapies was 2. Seven pts underwent prior autologous stem cell transplantation. Eight pts received prior radiation therapy. Six pts were stage II at initial diagnosis, 2 were stage III and 13 were stage IV. Rituximab 375mg/m2, gemcitabine 1000 mg/m2, vinorelbine at 100 mg/m2 and liposomal doxorubicin 30mg/m2 were administered on day 1 and day 8 of every 21 day cycle. Dose reductions were based on patient tolerability. Colony stimulating factors was used on day 9 of each cycle. Radiological studies were performed after 2 cycles or earlier if there was clinical suspicion for progression. The total number of cycles for all patients was 42 cycles. The major grade 3/4 toxicities were anemia in 42%, thrombocytopenia in 38%, neutropenia in 33%, infection in 14% and respiratory failure in 4% of patients. Objective responses were noted in 9 patients (42%). Three patients attained a complete response to therapy and 6 pts had a partial response or stable disease. The median progression free survival was 1.3 months. The median overall survival of all patients was 3.9 months. The three patients attaining a complete response had DLBCL of non-germinal center cell origin. Conclusions: R-GND is an alternative regimen with an overall response rate of 42% among patients with relapsed diffuse large B cell lymphoma. The interesting observation of the 3 patients who attained a complete response were of non-germinal center origin of DLBCL warrants further exploration of the role of gemcitabine based combination treatment in large cell lymphoma. Disclosures: No relevant conflicts of interest to declare.

Tyrosine kinase (TK) fusion proteins result from genomic rearrangements that juxtapose TK signaling domains with various upstream partners. Since tumor cells can become dependent upon the resultant constitutive kinase activity for tumorigenesis and survival, TK fusions serve as attractive therapeutic targets. However, identification of TK fusions in cancers has been hindered by experimental techniques that lack sufficient sensitivity and throughput. To overcome these challenges, we developed a screen to systematically identify TK fusions in tumor DNA. This method involves selective capture of regions upstream of GXGXXG kinase motifs where TK fusion breakpoints are likely to occur followed by next generation sequencing and custom computational analysis. This approach was previously validated using cell line DNA (Chmielecki et al, ‘10). Here, we used an improved version of our platform to identify a novel TK fusion using DNA isolated from whole blood of a patient with recurrent precursor T lymphoblastic lymphoma (T-ALL) who presented with new leukocytosis and bone marrow findings compatible with a myeloproliferative neoplasm (MPN) with eosinophilia. Cytogenetic analysis of a bone marrow aspirate prior to treatment for the patient's MPN revealed a karyotype with a t(5;6)(q33-34;q23). At recurrence, a 5q33/PDGFRβ rearrangement with a breakpoint proximal to the MYB locus on chromosome 6 was identified with fluorescence in situ hybridization (FISH). Prior to allogeneic hematopoietic cell transplantation, a brief trial of imatinib confirmed responsiveness of eosinophilia. To identify the exact fusion breakpoint, 3 µg of whole blood genomic DNA was subjected to genomic capture followed by paired-end SOLiD sequencing. Fusion candidates were validated by direct sequencing of PCR products generated with breakpoint spanning primers. Analysis of the recovered sequences identified a fusion involving c6orf204 upstream of the PDGFRβ TK domain. 5’-RACE confirmed expression of c6orf204-PDGFRβ mRNA in the patient's blood cells. Motif analysis of the 5’ c6orf204 sequence present within the fusion revealed a coiled-coil domain, which likely facilitates dimerization of the kinase, as observed in other TK fusions (e.g. BCR-ABL). Interestingly, retrospective FISH studies of the patient's diagnostic lymph node involved by T-ALL also revealed the presence of a PDGFRβ rearrangement. These data suggest that the rearrangement occurred in a multi-potent progenitor cell that gave rise to both the T-ALL and MPN. This finding is analogous to 8p MPNs involving FGFR1, but has not yet been reported with PDGFRβ. Further biochemical analysis of this TK fusion is currently underway, and additional tumor samples are undergoing screening for other novel TK fusions. This work was supported by an SU2C-AACR Innovative Research Grant to WP. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4977. doi:10.1158/1538-7445.AM2011-4977

Abstract 1763 Poster Board I-789 Introduction The myelodysplastic syndromes (MDS) are a group of aging-associated hematopoietic disorders characterized by ineffective maturation that, in 6-33% of cases, progress to acute leukemia (AML), a disease of blocked differentiation. Since microRNAs (miRNAs) regulate cell differentiation/maturation as well as cell identity, miRNAs may play critical roles in both the development of MDS as well as transformation to AML. With the advent of new therapies and treatment modalities for MDS and AML, the availability of biomarkers capable of detecting early MDS and predicting progression to AML would have tremendous impact on the management of these patients. Methods The study utilizes twenty samples of bone marrow mononuclear cells, ten from MDS patients and ten from normal controls, isolated and stored at the University of Pennsylvania Stem Cell Core Facility between 2003 and 2007. The MDS specimens included seven (7) from patients in whom it was known that no transformation to acute leukemia occurred within five (5) years of the available specimen and three (3) from patients in whom acute leukemia was diagnosed within two (2) years of the available specimen. The patient specimens were selected to represent early stage MDS and therefore not at high risk for transformation based on morphologic analysis (circulating blasts '5%) and the 2001 WHO classification system. Total RNA was obtained from each sample and arrayed on a custom Agilent miRNA microarray at the University of Pennsylvania Microarray Facility in a dual channel experiment in which each sample was arrayed against a pool of all twenty samples. Statistical analysis was performed using Genespring v 7.31 and Partek Genomics Suite v6.3. Subsequently, thirteen miRNAs of interest and one amplification control were examined by RT-PCR using ABI commercial primers for those targets. Total RNA extracted from formalin-fixed paraffin-embedded tissue was also examined for the relative expression of these fourteen miRNAs. Results Class discovery ANCOVA algorithms were applied to the data to identify 13 miRNAs which differentiate the MDS samples from the normal controls. Real time PCR was performed upon the sample RNAs to verify the microarray results. Of the thirteen candidate miRNAs, miR-150, miR-342, and miR-103, miRNAs documented in other studies to be important in hematopoiesis, demonstrate particular promise as classifiers for MDS based upon the high degree of correlation between the microarray results and the RT-PCR studies as well as their ability to independently differentiate MDS patients from normal controls. When the three miRNAs are taken together, the microarray and RT-PCR results correlate in 83% of cases, with only 2 major discrepancies. Furthermore, comparison between the total RNA isolated from the bone marrow mononuclear cells suspensions of two patients with total RNA isolated from the corresponding formalin-fixed paraffin-embedded clot sections, across fourteen different miRNAs demonstrate extremely high levels of correlation (R2 = 0.94 and 0.85), proving the feasibility of future studies utilizing the readily available paraffin-embedded clot sections as a source of patient samples. Microarray probes to predicted miRNAs were also identified which distinguished the three patients who progressed to acute myeloid leukemia within 24 months from the seven that did not. Conclusions A miRNA signature was identified which distinguishes early cases of MDS from normal controls. These miRNAs are predicted to regulate many of those mRNAs identified by traditional transcriptional profiling. Ultimately, it is hoped that assessment of miRNAs or their downstream targets will provide practicing pathologists with new markers for the identification of MDS and provide clinicians with additional prognostic information to guide the use of therapeutic interventions. Disclosures Carroll: Sanofi Aventis Corp: Research Funding; Cephalon Oncoloy: Consultancy.

16008 Background: While cancer patients have access to multiple sources of information, including mass media, the internet and personal and professional contacts, little is known about use of these sources in decision making. Methods: 43 patients with one of three cancer types (37% breast, 28% colon and 35% prostate, 58% stage 1) randomly recruited through the Pennsylvania Cancer Registry completed semi-structured in-person interviews about cancer related information acquisition and decision making. (Median age 59 (range 40–71), 47% male, 79% white, 74% married, mean education 14.6 years (SD = 2.48). Separate analyses were performed for actively looking for information (seeking) vs. passively coming across information (scanning). The primary endpoint was patient use of information sources in cancer related decision making. Results: All cancer patients reported use of both interpersonal and mass media information sources in making cancer related decisions. Patients with more advanced cancer (stage 3 vs. stage 1 or 2), higher education, and younger age were more likely to actively seek cancer information (χ2 = 4.7, p = .095, χ2 = 10, p = .04 and χ2 = 8.6, p = .07). Breast cancer patients and women were more likely to report passively coming across information (χ2 = 9.1, p = .058 and χ2 = 5.1, p = .078). Conclusions: Cancer information acquisition varied according to patient characteristics. Seeking was reported more in younger patients and those with higher formal education, and more advanced cancer. Highly educated and younger patients may be better at navigating the information environment; patients with more advanced cancer may have increased anxiety causing them to actively seek information. Scanning was more common among breast cancer patients and women. Women may attend to general health related information more than men or information about breast cancer may be more accessible and pervasive than information on colon or prostate cancer. No significant financial relationships to disclose.

The stereochemical and heterofunctional complexity of the polypropionate-derived macrolide antibiotics poses a formidable challenge for stereoselective synthesis, and these target structures have provided the stimulus for the development of a host of new enantioand diastereoselective bond constructions.1 In this paper we illustrate, in the context of an efficient synthesis of oleandolide aglycon (1),2 how polypropionate chains may be rapidly assembled using the chiral â-ketoimide building block 2 and its associated aldol reaction methodology recently developed in these laboratories.3,4 As illustrated in Scheme 1, the synthesis plan relied upon â-ketoimide 2 for the construction of both the C1-C8 and C9C14 oleandolide fragments. Concurrent application of a sequential aldol reduction strategy to both fragments established 8 of the 10 requisite stereocenters, while an imide enolate alkylation reaction was employed to control the lone C6 stereocenter in the C5-C8 subunit. In the final stereoselective transformation, the introduction of the C8-epoxide with the desired stereochemistry was effected through the directed VO(acac)2/t-BuO2H epoxidation of the 9-(S)-allylic alcohol prior to macrocyclization.5,6 This last step becomes much more challenging to implement when it is postponed until after macrocycle construction as the two previous syntheses of oleandolide have revealed.2 The synthesis of the C1-C8 fragment began with the titaniummediated syn aldol reaction between aldehyde 47 and â-ketoimide 2 (Scheme 2).3a,8 This double stereodifferentiating reaction (eq 1) proceeded in excellent yield with high anti Felkin diastereoselection. Treatment of aldol adduct 5 with Zn(BH4)2 established the C5-hydroxyl stereocenter Via a chelate-controlled