Lateralisation in agonistic encounters: do mirror tests reflect aggressive behaviour? A study on a West African cichlid

In this study, population level lateralisation and the suitability of mirror tests as a test of natural aggressive behaviour in male rainbow kribs Pelvicachromis pulcher was investigated. Aggressive behaviour in live agonistic trials correlated positively with behaviours towards a mirror image and no visual lateralisation was detected.

Abstract 3508: Inhibition of EZH2 overcomes resistance to sunitinib in clear cell renal cell carcinoma models

Background: Alterations in epigenetic mechanisms including histone modification and hyper-methylation at gene promoter regions have been implicated as mechanisms of drug resistance in cancer. Alternation of epigenetic regulators such histone methyltransferase, EZH2, has been reported in numerous cancer types including advanced renal cell carcinoma (RCC). Previous studies suggest that sunitinib may have a direct anti-tumor effect and that acquired sunitinib resistance may be induced in tumor cells rather than just in endothelial cells. In our study, we investigated the role of EZH2 in sunitinib resistance in clear cell renal cell carcinoma. Methods: Human RCC cell lines 786-0 were treated and exposed to increasing concentrations of sunitinib to develop a resistant cell line, 786-0R. Parental and resistant cell lines were treat with either sunitinib, GSK126 (EZH2 inhibitor) or both. In parallel, EZH2 was knocked down in 786-0 cells and exposed to increasing concentrations of sunitinib. Cell viability was quantitated by absorbance of crystal violet stained cells using a spectrometer at 570nm. In a second set of experiments, control and treated cells were collected for western analysis. Mice bearing human ccRCC patient derived xenograft (PDXs); RP-R-01, RP-R-02 and RP-R-02LM (a metastatic ccRCC model established from RP-R-02) were implanted into SCID mice either subcutaneously or orthotopic in the kidney (sub-renal). When tumors reached an average volume of 50mm3, mice were randomly grouped into 2 arms; control and sunitinib treatment (40mg/kg, 5days/week). Tumors volumes and body weight were assessed once per week. Tumor tissues and lungs were collected for immunohistochemistry analysis. All assessments and quantification were done blindly. Results: Our in vitro and in vivo data showed an increased expression of EZH2 with resistance to sunitinib. Furthermore, inhibition of EZH2 in our in vitro studies correlated with a significant decrease in the anti-tumor effect of sunitinib in both parental and resistant cell lines. Conclusion: Overall our data suggest the potential role of epigenetic alterations, specifically EZH2 overexpression and its association with resistance to sunitinib. We are currently assessing the effect of EZH2 inhibition with sunitinib resistance in our in vivo system using metastatic ccRCC PDX models.

Citation Format: Remi M. Adelaiye-Ogala, Sreenivasulu Chintala, Li Shen, Ashley Orillion, Eric Ciamporcero, May Elbanna, Kiersten Marie Miles, Bryan Gillard, Michael Buck, Roberto Pili. Inhibition of EZH2 overcomes resistance to sunitinib in clear cell renal cell carcinoma models. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3508. doi:10.1158/1538-7445.AM2015-3508

Abstract 4132: Anti-tumor and anti-metastatic effect of sunitinib in a patient derived metastatic clear cell renal cell carcinoma xenograft model

Background: Sunitinib, a multi-tyrosine kinase inhibitor, is considered first-line therapy for patient with advanced renal cell carcinoma. The mechanism by which sunitinib harnesses angiogenesis is by targeting receptors of pro-angiogenic growth factors such as VEGF, PDGF and kit. Recently, it has been speculated that sunitinib may have a direct anti-tumor effect. Our previous studies have shown that tumors resistant to sunitinib still present decreased tumor vasculature compared to untreated tumors, suggesting that sunitinib anti-tumor effect may be in part independent from its anti-angiogenic effect. Hence, we wanted to further investigate the anti-tumor effect of sunitinib in human renal cell carcinoma (RCC) cell lines and a patient derived clear cell RCC xenograft model. In addition, we examined the effect of sunitinib on early and late stage metastasis in a spontaneous metastatic human ccRCC model. Methods: Human ccRCC PDX RP-R-02 was implanted into SCID mice subcutaneously. Spontaneous metastatic ccRCC model, RP-R-02LM was developed from RP-R-02. RP-R-02LM tumor bearing mice were treated with sunitinib (40mg/kg; 5days/week). Tumor tissues and lungs were collected for immunohistochemistry analysis. In parallel, human RCC cell lines were treated in vitro with varying concentrations of sunitinib and cell viability was assessed. Results: Human RCC cells lines treated in vitro with sunitinib at pharmacological achievable concentrations showed a decrease in cell proliferation, suggesting a direct anti-tumor effect of sunitinib in RCC. RP-R-02LM but not parental RP-R-02 implanted either subcutaneous or orthotopically in the kidney, spontaneously metastasize to the lungs and closely mimics what is seen in the clinic. PCR results indicated that both xenografts still maintain human origin. In our in vivo system, RP-R-02LM treated with sunitinib had no anti-tumor effect on tumor at the primary site; however, we observed an inhibition of dissemination to the metastatic lung site as indicated by significantly low numbers of metastasis compared to the controls. Immunohistochemical analysis showed decrease in tumor vasculature with sunitinib treatment compared to the control, with increased tumor cell proliferations. Conclusion: Our studies suggest that sunitinib has a direct anti-tumor in vitro and eventually tumor cells acquire drug resistance. Our in vivo studies show that tumors resistant to sunitinib have decreased vessel density as compared to the untreated tumors, suggesting that sunitinib is still a potent anti-angiogenic agent. In addition, we show the anti-metastatic effect of sunitinib in a spontaneous metastatic human clear cell renal cell carcinoma. Overall our data suggest that sunitinib maintains an anti-metastatic effect in sunitinib resistant tumor bearing animals that is independent from its anti-angiogenic effect.

Citation Format: Remi M. Adelaiye-Ogala, Li Shen, Sreenivasulu Chintala, Eric Ciamporcero, Ashley Orillion, May Elbanna, Shengyu Ku, Kiersten Marie Miles, Bryan Gillard, Michael Buck, Roberto Pili. Anti-tumor and anti-metastatic effect of sunitinib in a patient derived metastatic clear cell renal cell carcinoma xenograft model. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4132. doi:10.1158/1538-7445.AM2015-4132

Sunitinib dose escalation overcomes transient resistance in clear cell renal cell carcinoma and is associated with epigenetic modifications

Sunitinib is considered a first-line therapeutic option for patients with advanced clear cell renal cell carcinoma (ccRCC). Despite sunitinib's clinical efficacy, patients eventually develop drug resistance and disease progression. Herein, we tested the hypothesis whether initial sunitinib resistance may be transient and could be overcome by dose increase. In selected patients initially treated with 50 mg sunitinib and presenting with minimal toxicities, sunitinib dose was escalated to 62.5 mg and/or 75 mg at the time of tumor progression. Mice bearing two different patient-derived ccRCC xenografts (PDX) were treated 5 days per week with a dose-escalation schema (40-60-80 mg/kg sunitinib). Tumor tissues were collected before dose increments for immunohistochemistry analyses and drug levels. Selected intrapatient sunitinib dose escalation was safe and several patients had added progression-free survival. In parallel, our preclinical results showed that PDXs, although initially responsive to sunitinib at 40 mg/kg, eventually developed resistance. When the dose was incrementally increased, again we observed tumor response to sunitinib. A resistant phenotype was associated with transient increase of tumor vasculature despite intratumor sunitinib accumulation at higher dose. In addition, we observed associated changes in the expression of the methyltransferase EZH2 and histone marks at the time of resistance. Furthermore, specific EZH2 inhibition resulted in increased in vitro antitumor effect of sunitinib. Overall, our results suggest that initial sunitinib-induced resistance may be overcome, in part, by increasing the dose, and highlight the potential role of epigenetic changes associated with sunitinib resistance that can represent new targets for therapeutic intervention.

Organ Specific Storage of Dietary Pyrrolizidine Alkaloids in the Arctiid Moth Creatonotos transiens

Larvae of the arctiid moth Creatonotos transiens obtained each 5 mg of heliotrine, a pyrrolizidine alkaloid, via an artificial diet. 7 S-H eliotrine is converted into its enantiomer, 7 R1-heliotrine, and some minor metabolites, such as callimorphine. 7 S- and 7 R-heliotrine are present in the insect predominantly (more than 97%) as their N-oxides. The distribution of heliotrine in the organs and tissues of larvae, prepupae, pupae and imagines was analyzed by capillary gas-liquid chromatography. A large proportion of the alkaloid is stored in the integument of all developmental stages, where it probably serves as a chemical defence compound against predators. Female imagines had transferred substantial amounts of heliotrine to their ovaries and subsequently to their eggs; males partly directed it to their pheromone biosynthesis.

Electrochemical investigation of covalently post-synthetic modified SURGEL coatings

Thiol–yne click chemistry post synthesis modification (PSM) is used to further functionalize a fully organic porous polymer coating (SURGEL). By cyclic voltammetry the resulting electrochemical properties are addressed. The Nernstian diffusion limited process observed in the presence of ferrocene as electrolyte is explained in terms of a high permeability of the SURGELs for ferrocene after PSM.

Facilitates chromatin transcription complex is an "accelerator" of tumor transformation and potential marker and target of aggressive cancers

The facilitates chromatin transcription (FACT) complex is involved in chromatin remodeling during transcription, replication, and DNA repair. FACT was previously considered to be ubiquitously expressed and not associated with any disease. However, we discovered that FACT is the target of a class of anticancer compounds and is not expressed in normal cells of adult mammalian tissues, except for undifferentiated and stem-like cells. Here, we show that FACT expression is strongly associated with poorly differentiated aggressive cancers with low overall survival. In addition, FACT was found to be upregulated during in vitro transformation and to be necessary, but not sufficient, for driving transformation. FACT also promoted survival and growth of established tumor cells. Genome-wide mapping of chromatin-bound FACT indicated that FACT's role in cancer most likely involves selective chromatin remodeling of genes that stimulate proliferation, inhibit cell death and differentiation, and regulate cellular stress responses.

The RecX protein interacts with the RecA protein and modulates its activity in Herbaspirillum seropedicae

DNA repair is crucial to the survival of all organisms. The bacterial RecA protein is a central component in the SOS response and in recombinational and SOS DNA repairs. The RecX protein has been characterized as a negative modulator of RecA activity in many bacteria. The recA and recX genes of Herbaspirillum seropedicae constitute a single operon, and evidence suggests that RecX participates in SOS repair. In the present study, we show that the H. seropedicae RecX protein (RecX Hs) can interact with the H. seropedicaeRecA protein (RecA Hs) and that RecA Hs possesses ATP binding, ATP hydrolyzing and DNA strand exchange activities. RecX Hs inhibited 90% of the RecA Hs DNA strand exchange activity even when present in a 50-fold lower molar concentration than RecA Hs. RecA Hs ATP binding was not affected by the addition of RecX, but the ATPase activity was reduced. When RecX Hs was present before the formation of RecA filaments (RecA-ssDNA), inhibition of ATPase activity was substantially reduced and excess ssDNA also partially suppressed this inhibition. The results suggest that the RecX Hs protein negatively modulates the RecA Hs activities by protein-protein interactions and also by DNA-protein interactions.

Study of electronic prescribing rates and barriers identified among providers using electronic health records in New York City

BACKGROUND

Increased electronic prescribing (eRx) rates have the potential to prevent errors, increase patient safety, and curtail fraud. US Federal meaningful use guidelines require at least a 40% electronic prescribing rate.

OBJECTIVE

We evaluated eRx rates among primary care providers in New York City in order to determine trends as well as identify any obstacles to increased eRx rates required by meaningful use guidelines.

METHODS

The data we analysed included automatic electronic data transmissions from providers enrolled in the Primary Care Information Project (PCIP) from 1 January 2009 to 1 July 2010 and follow-up telephone calls to a subset of these providers to identify potential barriers to increased eRx usage.

RESULTS

Over the course of the study, these providers increased the eRx rate from 12.9 to 27.5%, with an average rate of 24.1%. Conversations with providers identified their perceived barriers to increased eRx use as primarily patient preference for paper prescriptions and a belief that many pharmacies do not accept eRx.

CONCLUSIONS

The data gathered from our providers indicate that there is an increasing trend in the eRx rate to 27.5% by July 2010, but still short of the 40% meaningful use level. However, obstacles to increased rates remain primarily providers' belief that many patients prefer paper prescriptions and many pharmacies are not yet prepared to accept electronic prescriptions.

Physiologic and pharmacologic considerations for hypothermia therapy in neonates

With mounting evidence that hypothermia is neuroprotective in newborns with hypoxic-ischemic encephalopathy (HIE), an increasing number of centers are offering this therapy. Hypothermia is associated with a wide range of physiologic changes affecting every organ system, and awareness of these effects is essential for optimum patient management. Lowering the core temperature also alters pharmacokinetic and pharmacodynamic properties of medications commonly used in asphyxiated neonates, necessitating close attention to drug efficacy and side effects. Rewarming introduces additional risks and challenges as the hypothermia-associated physiologic and pharmacologic changes are reversed. In this review we provide an organ system-based assessment of physiologic changes associated with hypothermia. We also summarize evidence from randomized controlled trials showing lack of serious adverse effects of moderate hypothermia therapy in term and near-term newborns with moderate-to-severe HIE. Finally, we review the effects of hypothermia on drug metabolism and clearance based on studies in animal models and human adults, and limited data from neonates.

The evolution of the phage shock protein response system: interplay between protein function, genomic organization, and system function

Sensing the environment and responding appropriately to it are key capabilities for the survival of an organism. All extant organisms must have evolved suitable sensors, signaling systems, and response mechanisms allowing them to survive under the conditions they are likely to encounter. Here, we investigate in detail the evolutionary history of one such system: The phage shock protein (Psp) stress response system is an important part of the stress response machinery in many bacteria, including Escherichia coli K12.

Here, we use a systematic analysis of the genes that make up and regulate the Psp system in E. coli in order to elucidate the evolutionary history of the system. We compare gene sharing, sequence evolution, and conservation of protein-coding as well as noncoding DNA sequences and link these to comparative analyses of genome/operon organization across 698 bacterial genomes. Finally, we evaluate experimentally the biological advantage/disadvantage of a simplified version of the Psp system under different oxygen-related environments.

Our results suggest that the Psp system evolved around a core response mechanism by gradually co-opting genes into the system to provide more nuanced sensory, signaling, and effector functionalities. We find that recruitment of new genes into the response machinery is closely linked to incorporation of these genes into a psp operon as is seen in E. coli, which contains the bulk of genes involved in the response. The organization of this operon allows for surprising levels of additional transcriptional control and flexibility. The results discussed here suggest that the components of such signaling systems will only be evolutionarily conserved if the overall functionality of the system can be maintained.