Abstract C183: Pomhex: a cell-permeable high potency Enolase inhibitor with in vivo anti-neoplastic activity

Glycolysis inhibition is an active area of investigation in cancer. However, few compounds have progressed beyond the cell culture stage. We have recently demonstrated that genomic passenger deletion of the glycolytic enzyme Enolase 1 (ENO1) leaves gliomas harboring such deletions with less than 10% of normal enzymatic activity, rendering them exquisitely sensitive to enolase inhibitors. However, the tool compound that we employed for these in vitro studies, Phosphonoacetohydroxamate (PhAH), has very poor pharmacological properties and was ineffective in vivo. We performed a SAR studies to increase inhibitor specificity towards ENO2 as well as pro-druging to increase cell permeability. The lead compound generated by these efforts, termed POMHEX, is selectively active against ENO1-deleted glioma cells in culture at ∼35nM (versus μM for PhAH). Using an orthotopic intracranial xenografted model where tumor growth and response to therapy are monitored by MRI, we show that POMHEX is capable of eradicating intracranial ENO1-deleted tumors, with mice remaining recurrence-free even after treatment discontinuation. Taken together, these results reinforce that glycolysis is a viable target and provide in vivo proof-of-principal for the concept of using passenger deletions as targetable vulnerabilities in cancer therapy.

Citation Format: Yu-Hsi Lin, Joe Marszalek, Yuting Sun, Naima Hammoudi, Paul Leonard, David Maxwell, Nikunj Satani, Peng Zhang, Todd Link, Gilbert Lee, Maria E. Di Francesco, Barbara Czako, Alan Y. Want, Ronald A. DePinho, Florian L. Muller. Pomhex: a cell-permeable high potency Enolase inhibitor with in vivo anti-neoplastic activity. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr C183.

Historical Arctic Logbooks Provide Insights into Past Diets and Climatic Responses of Cod

Gadus morhua (Atlantic cod) stocks in the Barents Sea are currently at levels not seen since the 1950s. Causes for the population increase last century, and understanding of whether such large numbers will be maintained in the future, are unclear. To explore this, we digitised and interrogated historical cod catch and diet datasets from the Barents Sea. Seventeen years of catch data and 12 years of prey data spanning 1930–1959 cover unexplored spatial and temporal ranges, and importantly capture the end of a previous warm period, when temperatures were similar to those currently being experienced. This study aimed to evaluate cod catch per unit effort and prey frequency in relation to spatial, temporal and environmental variables. There was substantial spatio-temporal heterogeneity in catches through the time series. The highest catches were generally in the 1930s and 1940s, although at some localities more cod were recorded late in the 1950s. Generalized Additive Models showed that environmental, spatial and temporal variables are all valuable descriptors of cod catches, with the highest occurring from 15–45°E longitude and 73–77°N latitude, at bottom temperatures between 2 and 4°C and at depths between 150 and 250 m. Cod diets were highly variable during the study period, with frequent changes in the relative frequencies of different prey species, particularly Mallotus villosus (capelin). Environmental variables were particularly good at describing the importance of capelin and Clupea harengus (herring) in the diet. These new analyses support existing knowledge about how the ecology of the region is controlled by climatic variability. When viewed in combination with more recent data, these historical relationships will be valuable in forecasting the future of Barents Sea fisheries, and in understanding how environments and ecosystems may respond.

The prevalence of medical reasons for non-participation in the Scottish breast and bowel cancer screening programmes

Objective

Increasing uptake of cancer screening is a priority for health systems internationally, however, some patients may not attend because they are undergoing active treatment for the cancer of interest or have other medical reasons that mean participation would be inappropriate. This study aims to quantify the proportion of non-participants who have a medical reason for not attending cancer screening.

Methods

Medical reasons for not participating in breast and bowel screening were defined a priori on the basis of a literature review and expert opinion. The notes of 700 patients at two GP practices in Scotland were reviewed, to ascertain the prevalence of medical reasons amongst non-participants. Simple proportions and confidence intervals were calculated.

Results

17.4% of breast and 2.3% of bowel screening non-participants had a medical reason to not participate. The two most common reasons were previous breast cancer follow up (8.86%) and recent mammogram (6.57%).

Conclusion

These patients may not benefit from screening while also being distressed by receiving an invitation. This issue also makes accurate monitoring and target-setting for improving uptake difficult. Further work is needed to estimate robustly the extent to which medical reasons account for screening non-participation in a larger population.

Development and psychometric testing of an instrument to measure safety climate perceptions in community pharmacy

RATIONALE, AIMS AND OBJECTIVES

A positive and strong safety culture underpins effective learning from patient safety incidents in health care, including the community pharmacy (CP) setting. To build this culture, perceptions of safety climate must be measured with context-specific and reliable instruments. No pre-existing instruments were specifically designed or suitable for CP within Scotland. We therefore aimed to develop a psychometrically sound instrument to measure perceptions of safety climate within Scottish CPs.

METHODS

The first stage, development of a preliminary instrument, comprised three steps: (i) a literature review; (ii) focus group feedback; and (iii) content validation. The second stage, psychometric testing, consisted of three further steps: (iv) a pilot survey; (v) a survey of all CP staff within a single health board in NHS Scotland; and (vi) application of statistical methods, including principal components analysis and calculation of Cronbach's reliability coefficients, to derive the final instrument.

RESULTS

The preliminary questionnaire was developed through a process of literature review and feedback. This questionnaire was completed by staff in 50 CPs from the 131 (38%) sampled. 250 completed questionnaires were suitable for analysis. Psychometric evaluation resulted in a 30-item instrument with five positively correlated safety climate factors: leadership, teamwork, safety systems, communication and working conditions. Reliability coefficients were satisfactory for the safety climate factors (α > 0.7) and overall (α = 0.93).

CONCLUSIONS

The robust nature of the technical design and testing process has resulted in the development of an instrument with sufficient psychometric properties, which can be implemented in the community pharmacy setting in NHS Scotland.

Abstract 5361: Development of targeted inhibitors against RecQ1 helicase

Background: RecQ helicases are a ubiquitous family of DNA unwinding enzymes involved in the maintenance of chromosome stability. RecQ1 helicase genomic variations have an important prognostic role and represents a therapeutic target in pancreatic cancer [JCO 2006; 24 (11) 1720-1728]. Pubchem data indicated potential RecQ1 activity >600 compounds using a qHTS RecQ1 assay (NIH Chemical Genomics Center).

Methods: We applied a set of filters including molecular weight, potency and Hill curve fitting and also removed those interfering with biological assay to identify sixteen compounds for studying RecQ1 inhibition. Two compounds showed strong inhibition of RecQ1 helicase activity at 50 µM and at IC50 < 5 µM, respectively. From a large library of compounds, eight potential inhibitors were synthesized in three simple steps. First, sulfonylation of various amines with 3-Nitrobenzenesulfonyl chloride was performed followed by reduction of the nitro group into an amine. Finally, acylation with variety of acid chlorides resulted in the final library of RecQ1 analogs. These agents were studied for RecQ1 helicase activity assay with the radiolabeled partial duplex substrate in vitro. The RecQ1 inhibitor candidate compounds were investigated in pancreatic cancer cell lines (AsPC-1, BxPC-3, Capan-1, PANC-1, and Mia-Paca2) for anti-tumor efficacy using cell proliferation assay with CellTiter-Glo® luminescence. Combination studies with test compounds and poly (ADP ribose) polymerase (PARP) inhibitor olaparib and topoisomerase Inhibitor SN38 were performed. Results: Though none of the compounds showed the same level of activity of the parent compounds, we were able to demonstrate a modest level of helicase activity with several. Two compounds displayed strong inhibition of pancreatic cancer cell proliferation. Two other compounds displayed synergistic inhibition with SN38 or olaparib of pancreatic cancer cell proliferation and induced DNA damage.

Conclusions: Synthesis of RecQ1 inhibitors is feasible and shows potential for anti-tumor efficacy.

Note: This abstract was not presented at the meeting.

Citation Format: Mingxin Zuo, David Maxwell, Basvoju A. Bhanu Prasad, Zhenghong Peng, William Bornmann, Milind M. Javle. Development of targeted inhibitors against RecQ1 helicase. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5361. doi:10.1158/1538-7445.AM2014-5361

Abstract 2698: Degrasyn-like symmetrical compounds: Possible therapeutic agents for multiple myeloma (MM-I)

A series of degrasyn-like symmetrical compounds have been designed, synthesized, and screened against B cell malignancy (multiple myeloma, mantle cell lymphoma) cell lines. The lead compounds T5165804 and CP2005 showed higher nanomolar potency against these tumor cells in comparison to degrasyn and inhibited Usp9x activity in vitro and in intact cells. These observations suggest that this new class of compounds holds promise as cancer therapeutic agents.

Citation Format: William G. Bornmann, Zhenghong Peng, David Maxwell, Duoli Sun, Basvoju A. Bhanu, Moshe Talpaz, Nicholas Donato, Alexander Levitzki. Degrasyn-like symmetrical compounds: Possible therapeutic agents for multiple myeloma (MM-I). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2698. doi:10.1158/1538-7445.AM2014-2698

Chronic inactive pulmonary tuberculosis and treatment sequelae: chest radiographic features

The chest radiograph (CXR) is a key initial tool in the diagnosis of many lung conditions, including pulmonary tuberculosis (TB). With proper use of anti-tuberculosis drugs, TB can be treated effectively and many CXR changes are limited. However, anti-tuberculosis drugs have not always been available, and in some cases they have not been started early in the disease process. The infection has then been able to take hold and cause significant radiologically visible damage, such as calcification and fibrosis. Before the use of anti-tuberculosis drugs, a variety of surgical techniques were employed to control pulmonary infection, including plombage, oleothorax, phrenic nerve crush and thoracoplasty. Each of these led to distinctive CXR features. This article sets out to describe the CXR features of chronic disease and surgical treatments, as their increasing rarity with the passage of time has meant that they can be misinterpreted. However, with increasing life expectancy and the revival of surgery due to the development of anti-tuberculosis drug resistance, the correct interpretation of these CXR changes is still of importance.

Identification of the sentinel node by ultrasonography in patients with breast cancer

BACKGROUND

Identification of the sentinel node (SN) in patients with breast cancer is done by tracking a radioactive tracer, a vital dye, or both, as the marker(s) reach the axilla. Replacing this method with ultrasonographic (US) recognition of the SN could eventually spare patients the need for systemic anesthesia, permit minimally invasive outpatient biopsy of the node, and allow the formulation of a precise therapeutic plan before a definitive surgical procedure.

METHODS

Eighty-eight axillae of 84 patients with a histologic diagnosis of breast cancer were studied by injecting the subareolar area of the affected breast(s) with technetium 99 and an iron preparation before the planned surgical procedure and SN biopsy. An axillary US scan was performed in all patients before the injection of the markers. After induction of anesthesia, the SN was identified, needle-localized, and extracted under US guidance. Confirmation that the SN was retrieved was established by concordance with the audible gamma signal, unless there was none. All extracted nodes had iron stains performed.

RESULTS

All except three of the SNs were identified with US after the iron marker was injected, and all except six were identified by their radioactive signal. One of the SNs undetected on US was identified by its radioactive tracer, and the other two, although seen on US, had neither a gamma signal nor concordant iron deposits. All other SNs identified with US had a concordant audible signal when there was one, and all had concordant iron deposits on microscopy. Of the six SNs without a gamma signal, three without preincision activity were identified with US; three with neither a preincision nor an ex vivo signal were seen with US, but two of these were the SNs without a concordant iron deposit.

CONCLUSIONS

Using an iron preparation, the SN in patients with breast cancer can be identified with US with an accuracy equal to and perhaps better than that achieved with a radioactive tracer. These findings may change the current diagnostic model and affect the therapeutic algorithm of breast cancer patients.

Design and Synthesis of an Inositol Phosphate Analog Based on Computational Docking Studies

A virtual library of 54 inositol analog mimics of In(1,4,5)P₃ has been docked, scored, and ranked within the binding site of human inositol 1,4,5-trisphosphate 3-kinase A (IP₃-3KA). Chemical synthesis of the best scoring structure that also met distance criteria for 3'-OH to -P in Phosphate has been attempted along with the synthesis of (1S,2R,3S,4S)-3-fluoro-2,4-dihydroxycyclohexanecarboxylic acid as an inositol analog, useful for non-invasive visualization and quantitation of IP₃-3KA enzymatic activity.

Storage and control of optical photons using Rydberg polaritons

We use a microwave field to control the quantum state of optical photons stored in a cold atomic cloud. The photons are stored in highly excited collective states (Rydberg polaritons) enabling both fast qubit rotations and control of photon-photon interactions. Through the collective read-out of these pseudospin rotations it is shown that the microwave field modifies the long-range interactions between polaritons. This technique provides a powerful interface between the microwave and optical domains, with applications in quantum simulations of spin liquids, quantum metrology and quantum networks.

Remote Internet access to advanced analytical facilities: a new approach with Web-based services

Over the past decade, the increasing availability of the World Wide Web has held out the possibility that the efficiency of scientific measurements could be enhanced in cases where experiments were being conducted at distant facilities. Examples of early successes have included X-ray diffraction (XRD) experimental measurements of protein crystal structures at synchrotrons and access to scanning electron microscopy (SEM) and NMR facilities by users from institutions that do not possess such advanced capabilities. Experimental control, visual contact, and receipt of results has used some form of X forwarding and/or VNC (virtual network computing) software that transfers the screen image of a server at the experimental site to that of the users' home site. A more recent development is a web services platform called Science Studio that provides teams of scientists with secure links to experiments at one or more advanced research facilities. The software provides a widely distributed team with a set of controls and screens to operate, observe, and record essential parts of the experiment. As well, Science Studio provides high speed network access to computing resources to process the large data sets that are often involved in complex experiments. The simple web browser and the rapid transfer of experimental data to a processing site allow efficient use of the facility and assist decision making during the acquisition of the experimental results. The software provides users with a comprehensive overview and record of all parts of the experimental process. A prototype network is described involving X-ray beamlines at two different synchrotrons and an SEM facility. An online parallel processing facility has been developed that analyzes the data in near-real time using stream processing. Science Studio and can be expanded to include many other analytical applications, providing teams of users with rapid access to processed results along with the means for detailed discussion of their significance.

Abstract B64: Development of a novel strategy to overcome drug resistance by targeting ATP citrate lyase and de novo lipogenesis in colorectal cancer cells

Background: Colorectal cancer (CRC) is the second leading cause of cancer death in the United States. Although the response rate to current systemic therapies is ∼50%, drug resistance develops in nearly all patients leading to 50,000 deaths each year. Overcoming drug resistance involves understanding the mechanisms by which cancer cells adapt to the genotoxic stress. Metabolic changes at levels of mitochondria function, glucose metabolism, and de novo synthesis of fatty acids frequently occurs in malignant cells and impacts tumor development and growth. Our laboratory established in vitro drug-resistant models of CRC cells by chronic exposure of HT29 cells to increasing doses of chemotherapeutic agents (oxaliplatin, 5-FU and SN38) over a period of 4–6 months. We recently reported a metabolic switch to the glycolytic phenotype due to mitochondria defects in the oxaliplatin-resistant CRC cells (HT29-OXR) (Zhou et al, Cancer Research, 2012). In this study, we tested the hypothesis that deregulation of de novo lipogenesis pathways plays an important role in chemoresistance of CRC cells.

Methods: A previous study (Bose et al. Br J Ca, 2011) using unbiased proteomic profiling by mass spectroscopy (MS) was used to determine the proteomic signature of defective metabolic pathways in the oxaliplatin-resistant CRC cells (OXR cells). ATP-citrate-lyase (ACLy), the key enzyme of de novo lipogenesis pathway, was examined for protein levels and activation. The lipid content of resistant cells was examined by transmission electron microscope (TEM) and Oil Red staining. Transient knockdown of the ACLy protein by siRNA was used to study re-chemosensitization of the resistant cells. A small molecule inhibitor of ACLy was studied in combination with chemotherapeutic agents in resistant CRC cells for growth inhibitory (MTT assay) and cytotoxic effects (PARP cleavage and Annexin V staining). A cell free assay was used to test the potency of the ACLy inhibitor on ACLy activation.

Results: Activated ACLy protein level (phosphorylation on S454) was demonstrated by Western blot analysis in the HT29-OXR and SN38-resistant (HT29-SNR) cells, but not in 5-FU-resistant (HT29-FUR) cells. The OxR cells showed a 2–3 fold increase in lipid droplets numbers (by TEM examination) and fatty acid content (by Oil Red staining) than the parental cells. Furthermore, transient knockdown of the ACLy protein by siRNA demonstrated a return to chemosensitization when cells were treated with oxaliplatin. IC50 values of the ACLy inhibitor for parental HT29 and HT29-OXR, -SNR and —FUR cells were ∼30μM. As a single agent, the ACLy inhibitor blocked phosphorylation of ACLy and induced apoptosis in a concentration-dependent manner in parental HT29 cells, and its resistant derivatives -OXR and -SNR cells. Combination of the ACLy inhibitor at concentrations sufficient to block ACLy phosphorylation with oxaliplatin and SN38 showed enhanced effects on growth inhibition (MTT) and apoptosis induction (PARP cleavage and Annexin V assay) in HT29 cells-OXR and -SNR cells.

Conclusions: Chemoresistant CRC cells demonstrated: 1) increased de novo lipogenesis, 2) elevated levels of key lipogenesis enzymes ACLy, 3) dependence on ACLy activity for cell survival under cytotoxic stress. This metabolic switch likely contributes to the chemoresistant phenotype of CRC cells. Targeting an early step of de novo lipogenesis such as blocking ACLy activity may provide a novel strategy to overcome drug-resistance in CRC cells.

Abstract A129: Development of turmerax therapeutic compounds in aggressive, refractory B cell non-Hodgkin's lymphoma

Acquired chemoresistance (ACR) is currently the most important cause of treatment failure and early mortality in DLBCL, arguably the most important but greatest unmet need in lymphoma therapy today. Diffuse Large B cell Lymphoma (DLBCL), the most common human lymphoma, comprises a genetically and clinically diverse group of aggressive B cell non-Hodgkin lymphomas (NHL-B), among a small group of important human cancers increasing in incidence in the US over the last four decades. NHL-B are the fifth most common cancers in the USA (>62,000 new cases/20,000 deaths) expected in 2011. The molecular biologic and genetic basis of the patho-physiology of these important lymphoid tumors is still mostly unresolved.

Relapsed/refractory (r/rDLBCL) DLBCL is one of the most difficult scientific challenges and severe unmet therapeutic needs in clinical oncology today. This is due largely to 1.) very drug resistant tumor cells with very poor responses (<20% PR/CR) to current “salvage” therapies; and 2.) non-existent, invalid, or inadequate disease models, that we have recently been able to overcome, with development of valid chemo-refractory DLBCL a unique cell model library, derived from our patients, that now provides the opportunity to delineate critical previously unknown patho-physiologic biomarkers and in vivo molecular model mechanisms, while concurrently providing excellent models for new agent experimental therapeutics. We designed and synthesized novel inhibitors named Turmerax (TMX), when encapsulated with nano-liposomes to overcome solubility/bioavailability issues, is >1000x more effective than curcumin in inhibiting DLBCL growth and survival in vitro, and show no toxicities in normal peripheral blood lymphocytes. Liposomal-TMX (L-TMX) also targets multiple growth and survival signaling pathways, such as NF-kB and AKT, and key cellular regulatory proteins in drug resistance (MDR) in r/r DLBCL. We have also shown in vivo that L-TMX increases in survival time with decreases in lymphoma tumor burden in preliminary studies in SCID/MCL xeno-transplant (XT-SCID) models, without evidence of significant host toxicities. The development of our new agent nano-liposomal Turmerax, has provided a multi-targeted, non-toxic nano-therapeutic small molecule with the critical growth/survival (G/S) targeting specificities similar to natural product therapeutic agents (curcumin) but without the many foibles involving solubility, bioavailability, and poor in vivo potency problems, by providing a well-tolerated, well-delivered (in vivo) effective small molecule therapeutic agent, showing very promising preliminary activities on r/r DLBCL in xeno-transplant human DBLCL models, that appears to be an excellent candidate for future clinical trials.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A129.

A novel small molecule deubiquitinase inhibitor blocks Jak2 signaling through Jak2 ubiquitination

AG490 is a tyrosine kinase inhibitor with activity against Jak2 and apoptotic activity in specific leukemias. Due to its weak kinase inhibitory activity and poor pharmacology, we conducted a cell-based screen for derivatives with improved Jak2 inhibition and activity in animals. Two hits emerged from an initial small chemical library screen, and more detailed structure-activity relationship studies led to the development of WP1130 with 50-fold greater activity in suppressing Jak2-dependent cytokine signaling than AG490. However, WP1130 did not directly suppress Jak2 kinase activity, but mediated Jak2 ubiquitination resulting in its trafficking through HDAC6 to perinuclear aggresomes without cytokine stimulation or SOCS-1 induction. Jak2 primarily contained K63-linked ubiquitin polymers, and mutation of this lysine blocked Jak2 ubiquitination and mobilization in WP1130-treated cells. Further analysis demonstrated that WP1130, but not AG490, acts as a deubiquitinating enzyme (DUB) inhibitor, possibly through a Michael addition reaction. We conclude that chemical modification of AG490 resulted in development of a DUB inhibitor with activity against a DUB capable of modulating Jak2 ubiquitination, trafficking and signal transduction.

Cooperative atom-light interaction in a blockaded Rydberg ensemble

By coupling a probe transition to a Rydberg state using electromagnetically induced transparency (EIT) we map the strong dipole-dipole interactions onto an optical field. We characterize the resulting cooperative optical nonlinearity as a function of probe strength and density. We demonstrate good quantitative agreement between the experiment and an N-atom cooperative model for N=3 atoms per blockade sphere and the n=60 Rydberg state. The measured linewidth of the EIT resonance places an upper limit on the dephasing rate of the blockade spheres of <110 kHz.

Can the introduction of an integrated service model to an existing comprehensive palliative care service impact emergency department visits among enrolled patients?

PURPOSE

Fewer emergency department (ED) visits may be a potential indicator of quality of care during the end of life. Receipt of palliative care, such as that offered by the adult Palliative Care Service (PCS) in Halifax, Nova Scotia, is associated with reduced ED visits. In June 2004, an integrated service model was introduced into the Halifax PCS with the objective of improving outcomes and enhancing care provider coordination and communication. The purpose of this study was to explore temporal trends in ED visits among PCS patients before and after integrated service model implementation.

METHODS

PCS and ED visit data were utilized in this secondary data analysis. Subjects included all adult patients enrolled in the Halifax PCS between January 1, 1999 and December 31, 2005, who had died during this period (N = 3221). Temporal trends in ED utilization were evaluated dichotomously as preintegration or postintegration of the new service model and across 6-month time blocks. Adjustments for patient characteristics were performed using multivariate logistic regression.

RESULTS

Fewer patients (29%) made at least one ED visit postintegration compared to the preintegration time period (36%, p < 0.001). Following adjustments, PCS patients enrolled postintegration were 20% less likely to have made at least one ED visit than those enrolled preintegration (adjusted OR 0.8; 95% confidence interval 0.6-1.0).

CONCLUSION

There is some evidence to suggest the introduction of the integrated service model has resulted in a decline in ED visits among PCS patients. Further research is needed to evaluate whether the observed reduction persists.