Revision total knee replacement finances: a detailed cost-analysis of operative practice at a regional tertiary referral centre

BACKGROUND

The revision knee complexity classification (RKCC) stratifies knee revision operations depending on their level of complexity from simple revisions (R1) to highly complex cases (R3). Current financial codes used for calculation of reimbursement for knee revision services provided at the Trust, rely on patients' comorbidities. However, previous research has demonstrated that this approach may not yield an accurate financial account of knee revision arthroplasty cost. This is a single centre study from a secondary and tertiary revision unit, with work previously presented by the authors demonstrating that the majority of complex revision knee replacement within the region, take place in this unit. The aims of this study were to illustrate the current cost profile and renumeration service currently in place for revision knee and show the differences in cost based on complexity of the operation.

METHODS

In this retrospective study, 90 cases who underwent revision knee operations in 2019 were analysed. Data was obtained from a tertiary referral centre where the episodes had occurred. Mean cost, tariff, and subsequent deficit were calculated for the R1, R2 and R3 episodes.

RESULTS

R2 and R3 episodes were significantly more expensive than R1 episodes. The increase in cost between R3 and R2 episodes was not significant. The total cost of the revision operations was £1,162,343. Tariffs received for R2 and R3 revision operations were significantly more expensive than R1 operations. However, the increase in tariffs received for R3 operations was not significant in relation to R2 operations. The total amount of tariffs received by the Trust was £ 770,996 generating a net deficit of - £ 391,347.

CONCLUSION

Current financial coding for revision knee does not accurately predict costs associated with revision knee surgery. Net deficit varies depending on the RKCC grade of the knee revision episode with more complex operations resulting in a higher mean net deficit. Implementation of the RKCC could prove to be a useful tool in generating an accurate prediction of the cost associated with knee revision surgery.

Genomic Signatures of Local Adaptation under High Gene Flow in Lumpfish-Implications for Broodstock Provenance Sourcing and Larval Production

Aquaculture of the lumpfish (Cyclopterus lumpus L.) has become a large, lucrative industry owing to the escalating demand for "cleaner fish" to minimise sea lice infestations in Atlantic salmon mariculture farms. We used over 10K genome-wide single nucleotide polymorphisms (SNPs) to investigate the spatial patterns of genomic variation in the lumpfish along the coast of Norway and across the North Atlantic. Moreover, we applied three genome scans for outliers and two genotype-environment association tests to assess the signatures and patterns of local adaptation under extensive gene flow. With our 'global' sampling regime, we found two major genetic groups of lumpfish, i.e., the western and eastern Atlantic. Regionally in Norway, we found marginal evidence of population structure, where the population genomic analysis revealed a small portion of individuals with a different genetic ancestry. Nevertheless, we found strong support for local adaption under high gene flow in the Norwegian lumpfish and identified over 380 high-confidence environment-associated loci linked to gene sets with a key role in biological processes associated with environmental pressures and embryonic development. Our results bridge population genetic/genomics studies with seascape genomics studies and will facilitate genome-enabled monitoring of the genetic impacts of escapees and allow for genetic-informed broodstock selection and management in Norway.

Abstract 5344: High-throughput CRISPR-Cas9 knockout screens identify loss of miRNA1304-5p targeting the RAS/MAPK pathway as a modulator of resistance to ALK inhibitors in high-risk neuroblastoma

Anaplastic lymphoma kinase (ALK)-targeted therapy is a promising strategy for the treatment of ALK-positive neuroblastoma (NB). Several ALK tyrosine kinase inhibitors (ALK TKIs) have been approved for the treatment of Non-Small Cell Lung Carcinoma (NSCLC) and are currently in clinical trials for NB therapy. Recent evidence reported that ALK TKI resistance can occur in cancer patients, making the long-term efficacy of these therapies challenging. With the use of high-throughput and genome-wide CRISPR-Cas9 knockout screens, we identified loss of genes associated with decreased sensitivity to ALK TKIs in ALK-positive NB cells. Specifically, we discovered that CRISPR-Cas9 mediated knockout of miR-1304-5p desensitises ALK-positive NB to the ALK TKIs brigatinib and ceritinib. Inhibition of miR-1304-5p decreased, while mimics increased the sensitivity of NB cells to these ALK TKIs. Furthermore, we showed that miR-1304-5p targets the RAS/MAPK pathway, thereby decreasing cell viability via induction of apoptosis. Among the targets of miR-1304-5p, NRAS expression levels are of prognostic significance to NB patients suggesting it may drive an aggressive disease phenotype. Indeed, a combination treatment applying ALK TKIs and miR-1304-5p mimics increased treatment response. A similar effect was achieved using RAS pharmacological inhibition, which resulted in synergistic activity in MYCN Wild Type (WT) but had less effect on MYCN-amplified cells, suggesting that this pathway could be differentially regulated according to MYCN status. miR-1304-5p and NRAS expression, in patient-derived xenografts (PDXs) of high-risk NB harbouring ALK mutations, confirmed the relevance of this regulatory axis in NB and suggested that the reduced ALK TKI response in MYCN-positive PDXs could be due to inhibition of miR-1304-5p, and the combination of ALK and NRAS inhibition showed extraordinary anti-tumor efficacy compared to single agents. These findings suggest that the miR-1304-5p/NRAS axis alters the sensitivity of NB to ALK inhibitors and suggest that the modulation of this pathway in combination with ALK inhibition is a promising approach to improve NB treatment response and ultimately patient survival.

Citation Format: Perla Pucci, Liam Lee, Suzanne Turner, Leila Jahangiri, Jamie Matthews, Amos Burke, Patrick Reynolds, Lukas Kenner, Olaf Merkel, Fikret Rifatbegovic, Ji Luo, Peter Ambros, MiaoJun Han. High-throughput CRISPR-Cas9 knockout screens identify loss of miRNA1304-5p targeting the RAS/MAPK pathway as a modulator of resistance to ALK inhibitors in high-risk neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5344.

Chronotype and risk of post-menopausal endometrial cancer in the California Teachers Study

Working at night causes circadian disruption and it has been classified as a probable carcinogen. An evening chronotype, or preference for late day activity, has been shown to increase risk for several adverse health effects, such as metabolic disorders and recently, breast cancer. To further explore this emerging area of interest, we examined the association between endometrial cancer (EC) risk, another common cancer in women, and chronotype. The women in this study were members of the California Teachers Study cohort, which was established in 1995. Chronotype was reported on a subsequent questionnaire (Q5), administered in 2012-2013. The women included in this analysis were under age 90 years, were post-menopausal at Q5, and had no hysterectomy. The cancer cases, identified through linkages to the California Cancer Registry, were diagnosed between 1996 and 2014. We used unconditional logistic regression models to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of the associations between chronotype and EC diagnosis. There were 437 EC cases and 26,753 cancer-free controls included in this analysis. Controls were more likely to classify themselves as current morning chronotypes than were cases (39% and 34%, respectively). Compared to morning types, women who were definite evening types had a statistically significantly elevated OR of 1.44 (95% CI 1.09-1.91). This association was more pronounced among obese women as compared to non-obese women. For evening type compared to morning type, the OR among obese women was 2.01 (95% CI 1.23, 3.29) while the OR for non-obese women was 1.12 (95% CI 0.77, 1.63). To our knowledge, the association between EC risk and evening chronotype has not been previously reported, but is consistent with the small body of literature which suggests increased breast cancer risks among evening chronotypes. Because this study was based on a retrospective analysis in a cohort of mostly white female teachers in California, further analysis of chronotype as a potential EC risk factor should be considered in other cohorts and in prospective analyses in order to further explore this relationship.

RARE-08. POTENTIAL NEW THERAPIES FOR DIFFUSE INTRINSIC PONTINE GLIOMAS IDENTIFIED THROUGH HIGH THROUGHPUT DRUG SCREENING

Diffuse Intrinsic Pontine Gliomas (DIPGs) are the most devastating of all brain tumors. There are no effective treatments, hence almost all children will die of their tumor within 12-months. There is an urgent need for novel effective therapies for this aggressive tumor. We performed a high-throughput drug screen with over 3,570 biologically active, clinically approved compounds against a panel of neurosphere-forming DIPG cells. We identified 7 compounds - auranofin, fenretinide, ivermectin, lanatoside, parthenolide, SAHA and mefloquine - that were confirmed to have potent anti-tumor activity against a panel of DIPG-neurospheres, with minimal effect on normal cells. Using cytotoxicity and clonogenic assays, we found that these drugs were able to inhibit DIPG-neurosphere proliferation and colony formation in vitro. To determine whether the in vitro efficacy could be replicated in vivo, we tested the activity of each of these compounds in an orthotopic DIPG model. Of the agents tested, fenretinide, auranofin and SAHA were the most active anti-tumor agents, significantly enhancing the survival of tumor bearing animals. Mechanistic studies showed fenretinide enhancing apoptotic cell death of DIPG cells via inhibition of PDGFRa transcription and downregulation of the PI3K/AKT/MTOR pathway. We therefore examined the therapeutic efficacy of fenretinide using a second orthotopic model with PDGFRa amplification. We used two different fenretinide formulations which were found to enhance survival. Fenretinide is clinically available with safety data in children. Validation of the activity of Fenretinide in PDGFRa-amplified or overexpressed DIPGs will lead to the development of a clinical trial, allowing the advancement of fenretinide as potentially the first active therapy for DIPG.

Abstract P468: Functional Outcome of Patients Undergoing Mechanical Thrombectomy Outside of the Dawn and Defuse Criteria

Background: The DAWN and DEFUSE trials (D&D) extended the mechanical thrombectomy (MT) window to 16-24 hours from last known normal (LKN) in patients with internal carotid artery (ICA) or proximal middle cerebral artery (M1) large vessel occlusions (LVO), with limits on core infarct and penumbra size. With advances in imaging and procedural techniques, many have extended these results to patients outside of the study criteria, yet there is limited analysis of outcomes in those receiving MT beyond these guidelines. This study evaluates the functional outcome of MT in acute stroke patients presenting within 24 hours of LKN outside of the D&D criteria vs those meeting study criteria at a single Comprehensive Stroke Center.

Methods: An IRB approved study was performed in which consecutive anterior circulation ischemic stroke patients presenting to Wake Forest Baptist Health from 12/1/18-12/31/19 within 0-24 hours of LKN were retrospectively studied. Patients were grouped by eligibility for DAWN or DEFUSE (mRS ≦1, ICA/M1 occlusion, age <80 NIHSS ≧10 and core 0-30, or age <80 NIHSS ≧20 and core 31-51, or age ≧80 NIHSS ≧10 and core 0-20; or mRS ≦2, NIHSS ≧6, ICA/M1 occlusion with core <70, mismatch volume >15, and mismatch ratio >1.8) or neither. Good outcome was defined as mRS ≦3 within 3 months of discharge. If not available, discharge mRS was used. A multivariate logistic regression model analyzed the outcome controlling for confounding factors.

Results: Of 130 patients, 57 (44%) fell outside D&D criteria. There was no significant difference between age, rate of IV tPA, admission NIHSS, baseline co-morbidities, or core infarct size between groups. Median mismatch volume was greater in the D&D group compared to patients in the non D&D group (97cc, IQR 67-146 vs 67cc, IQR 30-111; p=0.002). Good outcome was seen in 34 (47%) D&D patients vs 30 (53%) in the non D&D group; controlling for confounding factors affecting 3 month mRS (age, NIHSS, time to revascularization, atrial fibrillation, prior stroke), this was not statistically significant (p=0.25).

Conclusion: The outcome of MT in patients with anterior circulation LVO is not different between those meeting and not meeting D&D criteria. MT should be considered in patients presenting within 24 hours outside study guidelines.

DIPG-07. HIGH THROUGHPUT DRUG SCREENING IDENTIFIES POTENTIAL NEW THERAPIES FOR DIFFUSE INTRINSIC PONTINE GLIOMAS (DIPGs)

DIPGs are the most devastating of all brain tumors. There are no effective treatments, hence almost all children will die of their tumor within 12 months. There is an urgent need for novel effective therapies for this aggressive tumor. We performed a high-throughput drug screen with over 3,500 biologically active, clinically approved compounds against a panel of neurosphere-forming DIPG cells. We identified 7 compounds- auranofin, fenretinide, ivermectin, lanatoside, parthenolide, SAHA and mefloquine- that were confirmed to have potent anti-tumor activity against a panel of DIPG-neurospheres, with minimal effect on normal cells. Using cytotoxicity and clonogenic assays, we found that these drugs were able to inhibit DIPG-neurosphere proliferation and colony formation in-vitro. To determine whether the in-vitro efficacy could be replicated in-vivo, we tested the activity of each of these compounds in an orthotopic DIPG model. Of the agents tested, fenretinide and SAHA were the most active anti-tumor agents, significantly enhancing the survival of tumor bearing animals. Mechanistic studies showed fenretinide enhancing apoptotic cell death of DIPG cells via inhibition of PDGFRa transcription and downregulation of the PI3K/AKT/MTOR pathway. We therefore examined the therapeutic efficacy of fenretinide using a second orthotopic model with PDGFRa amplification. We used two different Fenretinide formulations (LYM-X-Sorb and NanoMicelle) which were found to enhance survival. Fenretinide is clinically available with safety data in children. Validation of the activity of Fenretinide in PDGFRa-amplified or overexpressed DIPGs will lead to the development of a clinical trial, allowing the advancement of fenretinide as potentially the first active therapy for DIPG.

Stress-Dosed Glucocorticoids and Mineralocorticoids Before Intensive Endurance Exercise in Primary Adrenal Insufficiency

Patients with primary adrenal insufficiency (PAI) require increased doses of glucocorticoids and mineralocorticoids during stressors, such as surgery, trauma, and sepsis. Although current guidelines exist for dose adjustments in these situations, there is no accepted dosing regimen for patients with PAI participating in intensive endurance exercise. Given the extensive physiologic stress of events, such as marathons, triathlons, and similar events, it is likely that a "stress-dose" of adrenal replacement therapy will not only prevent adrenal crisis, but also improve performance. A 50-year-old male endurance athlete with known PAI reported severe fatigue, nausea, and malaise after competing in prior marathons and intensive endurance exercise. After supplementing with glucocorticoids and mineralocorticoids before competition, he experienced decreased symptoms and improved performance. To better care for these patients, further studies should be conducted to provide safe and effective glucocorticoid and mineralocorticoid dose adjustments before intensive endurance exercise.

Performing Under Pressure: Varsity Athletes Excel in Medical School

PURPOSE

The admission process for medical school relies on objective and subjective measures of personal achievement, and selecting successful medical students is a daunting task for admission committees. While there is a significant body of literature examining MCAT scores and undergraduate grade point average (GPA) with medical school performance, there is a paucity of research on impact of specific student accomplishments on future performance. We hypothesize participation in a varsity collegiate sport will correlate with higher performance during medical school.

METHODS

A retrospective review of four medical school classes at a single institution was completed. Each student's admission application was examined for at least 1 year of participation in a varsity-level sport at their respective undergraduate institution. A total of 62 athletes (16.36%) were identified out of 441 total students. Multiple medical school performance metrics were obtained for each student.

RESULTS

There was no difference in MCAT scores between athletes and non-athlete medical students. There was a significant difference in step 1, step 2 CK, NBME shelf exams, cumulative year 3 performance, and AOA status with the athletes outperforming their peers.

CONCLUSION

Students who participate in collegiate varsity athletics excel in medical school. One explanation for this finding may be participation in high-stakes athletic training and competition results in development of specific attributes beneficial in medical school. These attributes may include receptiveness to criticism, time management, resiliency, team participation, and performing under pressure. Additional research is needed to elucidate the attributes that determine improved medical school performance, such that medical educators can utilize this knowledge to better prepare all students for the rigors of medical school.

Abstract 781: The tumor suppressive microRNA-15 family targets MYCN in neuroblastoma

Background: Neuroblastoma is the most common extracranial solid malignancy in children. Amplification/stabilization of the MYCN oncogene defines a group of neuroblastoma with a high risk of recurrence. Despite current aggressive treatment regimens, the prognosis for high-risk neuroblastoma patients remains poor with survival less than 40%. Most of the affected children ultimately die of the disease, which highlights the urgent need for novel therapeutic approaches. MicroRNAs (miRNAs) are small non-coding RNAs with gene expression regulatory functions whose expression is dysregulated in all types of human cancers, including neuroblastoma. However, the role of miRNAs in the regulation of MYCN and the development of drug resistance is currently unknown.

Hypothesis: We hypothesize that miRNA-15 family act as a tumor suppressor in neuroblastoma.

Methods: Neuroblastoma patient tumors were expanded in vivo. miRNAs were profiled by Nanostring and validated by qRT-PCR using TaqMan assays. miRNAs or their inhibitors were overexpressed by lipid reagent mediated transfection or lentiviral infection. Western blotting and qRT-PCR assays detected MYCN expression. Luciferase reporter and Ago-2 immunoprecipitation assays were performed to test miRNA-15 directly targeting of MYCN through interaction with 3’UTR of MYCN mRNA. Cell proliferation assay was carried out through MTT; cell migration by wound-healing; whereas invasion by examining the ability of cells to pass through a Matrigel-coated membrane matrix in neuroblastoma cells. Tumor growth was measured in neuroblastoma xenografts treated with neuroblastoma cells alone or with miRNA-15. MYCN (mRNA and protein), and miRNA-15 levers were assessed in xenograft tumors. Student’s t-test was used to evaluate the differences between treatment groups. All statistical tests were two-sided.

Results: Based on the MYCN expression, neuroblastoma patient-derived xenografts (PDX) were divided into MYCN higher and lower expression. miRNA-15 family such as miRNA-15a-5p, miRNA-15b-5p, and miRNA-16-5p were downregulated in PDX with higher MYCN expression. By luciferase and Ago-IP assays, we found miRNA-15a-5p, miRNA-15b-5p, and miRNA-16-5p can directly bind with 3’UTR region of the MYCN mRNA. R2 database involving 105 neuroblastoma patients show an inverse correlation between MYCN mRNA and miRNA-15 host gene. The forced expression of the miRNA-15a-5p, miRNA-15b-5p, and miRNA-16-5p in neuroblastoma cells resulted in a significant reduction in the levels of MYCN and suppressed cell proliferation, migration, and invasion. Conversely, the inhibition of miRNA-15 family expression dramatically accelerated MYCN expression. Injection of neuroblastoma cells with miRNAs inhibits the tumor formation in neuroblastoma xenografts.

Conclusion: These data suggest that miRNA-15 family may function as a tumor suppressor by targeting MYCN in neuroblastoma.

Citation Format: Kishore B. Challagundla, Patrick Reynolds, Santhi Gorantla, Larisa Poluektova, Don Coulter, Surinder K. Batra, Srinivas Chava. The tumor suppressive microRNA-15 family targets MYCN in neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 781.

It works! Lumpfish can significantly lower sea lice infestation in large-scale salmon farming

To assess the efficacy of lumpfish grazing on attached sea lice on Atlantic salmon, six large-scale sea cages, (130 m circumference, 37,688 m³ volume) each stocked with approximately 200,000 salmon 0+ smolts, were stocked with a 4, 6 and 8% density (8000, 12,000 and 16,000, respectively) of lumpfish. The sea cages without lumpfish acted as controls. Sea lice infestation levels on the salmon were monitored weekly and bi-weekly from 6 October to 17 May the subsequent year. Mortality of the lumpfish rose with decreasing sea temperatures to around 0.8% week^-1 and did not vary between the lumpfish groups. There were clear signs of lumpfish grazing on sea lice, with significantly lower average levels of chalimus, pre-adult and adult female Lepeophtheirus salmonis and Caligus elongatus sea lice per salmon. Lumpfish in the high density (8%) group reduced the mature female L. salmonis to levels equal to or lower than the counts recorded prior to the start of the study. Overall, the present results indicate that lumpfish are a suitable cold-water option for biological delousing of Atlantic salmon in large-scale production conditions.

Role of Early Palliative Care Interventions in Hematological Malignancies and Bone Marrow Transplant Patients: Barriers and Potential Solutions

INTRODUCTION

Despite advances in palliative care management of physical, psychological, and emotional symptoms along the spectrum of chronic conditions, early palliative care interventions are not used frequently and comprehensively in bone marrow transplant units.

METHODS

The literature review of PubMed articles in English published until December 2017.

RESULTS

Patients with hematologic malignancies and bone marrow transplant interventions are a heterogeneous group. The majority experience symptoms associated with induction or condition regimens. Curative intent of treatment is the norm. Pain, mucositis, nausea and vomiting, diarrhea, psychological, spiritual, and emotional concerns may not be properly and comprehensively tackled by primary oncology and bone marrow transplant teams. Quality of life may be decreased due to the presence of these symptoms. Obstacles to early palliative care interventions include overestimation of survival, focus on curative intent with underestimation of palliative care needs, lack of a comprehensive understanding of hematologic malignancies and bone marrow transplant process on the side of palliative care providers, and logistical restrictions. Potential interventions include education of oncologists, palliative care providers, patients, integration of models of care pre- and posttreatment and bone marrow transplantation, development of guidelines, institutional commitment and leadership in creating new initiatives, clinical research activities to measure outcomes, and community-based participatory research.

CONCLUSIONS

Early palliative care interventions are beneficial for patients with hematologic malignancies and bone marrow transplant processes. Better understanding of barriers to its implementation and development of creative initiatives is of paramount importance. New research endeavors should focus on providers' attitudes toward patients and communities.

Abstract 5506: SOX11 acts as part of the MYCN-WEE1 regulatory protein complex implicated in neuroblastoma

Neuroblastoma (NB) is an aggressive lethal pediatric cancer of the developing sympatho-adrenergic nervous system and characterised by a low mutation burden while exhibiting recurrent DNA copy number alterations including chromosome 2p gain and MYCN amplification. Rare amplifications have previously allowed to identify additional oncogenes implicated in NB such as ALK and LIN28B.

Here we report on three NB tumours and two NB cell lines with high level focal gain containing the SRY-related HMG-box transcription factor 11 (SOX11) as only protein-coding gene in the smallest region of overlap. The high expression levels of SOX11 in NB and the developing sympathetic nervous system, and high correlation of SOX11 mRNA and protein levels with survival outcome, suggested a role for SOX11 as oncogene and prompted us to further investigate its role in MYCN driven NB formation. SOX11 knock down in NB cell lines showed reduced colony formation capacity and G1-S cell cycle arrest. We observed increased SOX11 levels upon MYCN induction in NB cell lines, in MYCN overexpressing mouse neuroblastomas compared to normal ganglia as well as a high correlation of SOX11 and MYCN mRNA and protein levels in cell lines and tumors. As these data could indicate direct MYCN regulation of SOX11, we performed MYCN ChIPseq and indeed confirmed binding of MYCN to the SOX11 promotor. Next, we demonstrated MYCN and SOX11 cooperative binding to common targets using SOX11 and H3K27ac ChIP-sequencing. First, we showed localisation of more than half (62%) of the SOX11 binding sites at enhancers. Moreover, 19% of SOX11 targets contained an E-Box motif, typically known to be targeted by MYCN, and we showed overlap of 30% of SOX11 and MYCN binding targets. In a further step to unravel SOX11 function in NB cells, we analysed SOX11 binding partners using IP-MS and identified 9 robust interaction partners in multiple NB cell lines. These included MYCN which was confirmed by reciprocal co-IP, as well as WEE1, a tyrosine kinase critically implicated in G2-M checkpoint control for which multiple potent and specific small molecule inhibitors are available. Remarkably, upon testing of the AZD-1775 WEE1 inhibitor in 10 NB cell lines, we observed the strongest effects in cells with the highest SOX11 protein levels indicating that SOX11 expression levels can serve as predictive biomarker for AZD-1775 treatment response.

In conclusion we identified high-level focal gain of SOX11 in NB tumors and cell lines and demonstrated the oncogenic role of SOX11 in MYCN driven neuroblastoma with therapeutic opportunities through interaction with WEE1.

Citation Format: Bieke Decaesteker, Sara De Brouwer, Fanny De Vloed, Geertrui Denecker, Suzanne Vanhauwaert, Jolien De Wyn, Geneviève Laureys, Bjorn Menten, Pauline Depuydt, Patrick Reynolds, Jo Vandorpe, Kris Gevaert, Jan Koster, Sara Ek, Frank Speleman, Katleen De Preter. SOX11 acts as part of the MYCN-WEE1 regulatory protein complex implicated in neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5506. doi:10.1158/1538-7445.AM2017-5506

Abstract P5-09-09: Functional IGF1R variant predicts preeclampsia protection from invasive breast cancer: Novel California teachers study findings

Many studies have reported lower breast cancer risk in women who develop hypertension in pregnancy with a meta-analysis reporting hazard ratios of 0.86 for preeclampsia and 0.83 for gestational hypertension. Our prior work in the Marin Women's Study (MWS) demonstrated both a lower breast density and a lower risk of breast cancer in women with pregnancy-induced hypertension (PIH) if they possess the TT genotype of IGF1R SNP rs2016347.

Breast cancer in MWS women with PIH by IGF1R genotypers2016347 genotype# with genotype# breast cancer cases% breast cancer casesGG9188.79%GT195147.18%TT8800.00%Fisher's exact = 0.008

The current study was designed to validate and expand upon these findings in the larger California Teachers Study (CTS) which consists of &gt;130,000 female educators. From original participants a case-control study was established in 2012 consisting of all non-Hispanic white women with DNA samples that became cases since entry into the study (N = 2030) and controls without invasive or in situ breast cancer (N = 1552). The current study nests within this case control study. All participants with a self-reported history of preeclampsia were selected (81 cases/56 controls). IGF1R SNP rs2016347 was assessed by Taqman assay.

Results: Women with the TT genotype had an odds ratio (OR) of 0.38 when compared to the GG genotype after adjusting for potential confounders. Stratification by HR+/HR- cases and by age of first birth (AFB) resulted in statistically significant adjusted OR's of 0.26 for HR+ positive cases and 0.15 for women with AFB &lt;30. Both showed significant trend effect for number of T alleles as shown below:

Preeclampsia and breast cancer in CTSrs2016347 genotypeAll cases (N=137)HR+ cases (N=118)AFB &lt;30 (N=106)TT vs GG0.38 (0.13, 1.14)0.26 (0.07, 0.89)*0.15 (0.04, 0.56)*GT vs GG0.53 (0.19, 1.46)0.57 (0.19, 1.74)0.34 (0.12, 1.12)Trend analysisp = 0.09p = 0.03*p = 0.005** p &lt; .05

Overall in the CTS, the adjusted hazard ratio for women with vs without preeclampsia was 0.94 (0.81, 1.08).

Conclusions: These results suggest significant breast cancer protection in women with preeclampsia that possess the TT genotype, specifically in those women with AFB &lt;30, and for the development of HR+ breast cancer. The overall OR for all women with the TT genotype was low at 0.38 but did not reach statistical significance. This analysis in a second cohort again demonstrates a lower risk of breast cancer in women with a hypertensive disorder of pregnancy possessing the same IGF1R variant.

Recent studies have associated the rs2016347 T allele with lower normal tissue expression of IGF1R mRNA, better survival in HR+ breast cancer, and improved pathological response to neoadjuvant chemotherapy. The protective T allele creates a new microRNA (miR-432) binding site within the IGF1R 3'UTR, offering a potential functional explanation for reduced mammary gland expression of this cancer-associated growth factor. This may interact with alterations of growth and metabolic factors characteristic of preeclampsia to imprint the immature gland with a lasting protective effect from later life breast tumorigenesis. If mechanistically substantiated, these findings could lead to a novel breast cancer prevention strategy.

Citation Format: Powell M, Von Behren J, Neuhausen S, Reynolds P, Benz C. Functional IGF1R variant predicts preeclampsia protection from invasive breast cancer: Novel California teachers study findings [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-09-09.

Inpatient Falls: Improving assessment, documentation, and management

A frequently occurring job during on-call and out-of-hours shifts is reviewing a patient following a fall with this often being the responsibility of the most junior and inexperienced doctors. Following a pilot audit we identified inconsistencies in medical assessment and documentation, with 50% of expected data points not recorded.

Failure to complete a thorough assessment can lead to missed injuries, prolonged length of stay, and litigation. Using the plan, do, study, act (PDSA) cycle model this project sought to address this through providing teaching to junior doctors and the development of a pro-forma.

Three style cycles of data collection were performed; a formal baseline dataset, after delivering a teaching session to new junior doctors and following the trial of the new fall pro-forma. We selected 15 to 17 patient notes to review at random during a one month period for each data collection cycle and compared the medical assessment to the standards outlined by the National Patient Safety Agency (NPSA) guidelines.[1]

There were two key areas of improvement identified following the teaching session and introduction of the proforma. Documentation of a fall history was improved by nearly 30% being recorded in 100% of cases after the interventions. Documentation of a thorough musculoskeletal examination was improved from being recorded in just 54% of cases to 77% of cases; it was recorded in 100% of the cases where the proforma was used.

The project demonstrated the need to improve documentation and assessment of a patient who has fallen. Initial data collection has shown that assessment and documentation were improved providing teaching to junior doctors and by use of the document. The pro-forma has since been incorporated into hospital policy and now forms the compulsory documentation expected of the doctors and nurses managing patients following a fall. Ensuring easy access to the proforma and re-auditing after editing the document will be the next steps.

Abstract 484: Fidelity of subclonal representation in human neuroblastoma-derived cell line and patient-derived xenograft models: A report from the NCI-TARGET project

Patient-derived xenografts and cell lines have been the underpinning of functional characterization and drug discovery efforts in cancer. The use of these models is often under the assumption that these systems are renewable, faithful representations of original progenitor tumor cell populations. To test this assumption, we performed whole exome (92X median coverage) and genome sequencing (36X median coverage) analysis of cell line and patient-derived mouse xenografts (PDXs) originating from 7 neuroblastoma patients. Data are from1 primary tumor, 3 PDXs, and 15 neuroblastoma cell lines cultured from tumor, bone marrow, or blood. The cell lines consisted of 4 pre-/post-therapy pairs and 3 pairs established and maintained in either hyperoxia (room air i.e. “standard” cell culture) or physiologic (bone marrow hypoxia = 5%) oxygen. 7 lymphoblastoid or fibroblast cell lines were used as matched normals to identify somatic mutations. Subclonal population structures were inferred from somatic mutation calls calibrated for copy number state and tumor purity.

In all cell lines and xenografts, we observed 1-2 additional subclonal populations, primarily supported by deep coverage from exome sequencing. In nearly every case, we observed shifts in the proportional representation of genetic subclones and many subclones showed additional mutations not evident in the progenitor tissue or cancer line derived in parallel. Comparison of three cell line pairs established in bone marrow level hypoxia versus room air found only ∼40% of coding mutations in each line were shared (average 82 mutations per line), suggesting significant genetic impact of growing tumor cells in the two different culture conditions. Matched PDXs from these cases had only ∼17% of coding mutations shared across all three models. The greatest genetic similarity was seen between paired cell lines established from tissue obtained pre-/post-therapy from the same patient (36 coding mutations shared, 14 private to diagnosis and 13 private to progression). However, a second pre/post-therapy cell line pair did not share any coding mutations, although they did have 585 non-coding mutations in common (of 4,033 and 2,480 in each line), assuring that the relapse was derived from a diagnostic tumor clone. These results highlight a need for comprehensive subclonal analysis of human cancer laboratory models to better inform design and interpretation of biological and preclinical therapeutic studies.

Citation Format: Maya Schonbach, Arnavaz Danesh, Jeff Bruce, Tito Woodburn, Tanja Davidsen, Leandro Hermida, Patee Gesuwan, Jaime Guidry Auvil, Oliver Hampton, David Wheeler, Julie Gastier-Foster, Malcolm Smith, Daniela Gerhard, John M. Maris, Patrick Reynolds, Trevor J. Pugh. Fidelity of subclonal representation in human neuroblastoma-derived cell line and patient-derived xenograft models: A report from the NCI-TARGET project. [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 484. doi:10.1158/1538-7445.AM2015-484

Pilot study to assess effects of collection tube types and processing delay on measurements of persistent organic pollutants and lipids in human serum

Glass red top tubes (RTs), traditionally used to draw blood for biomonitoring studies, have some limitations during field sampling (e.g., tube breakage, timely processing may be difficult). This pilot study examined whether serum separation tubes (SSTs) with delayed processing time (48 h) can be used instead of red top tubes (RTs) to accommodate field conditions. Using state-of-the-art methodologies, PBDEs, PCBs, OCPs, PFCs, cholesterol and triglycerides were measured to evaluate any differences among 2 test conditions (RTs with 2h processing time; SSTs with 48 h processing time). Between the 2 test conditions, we observed high rank correlations among the measured compounds and no statistically significant differences in the levels of measured compounds. We conclude that SSTs with delayed processing time (48 h) produce similar results as RTs with short processing time (2h), suggesting that SSTs could be good substitutes for RTs for new epidemiological and biomonitoring field studies. The use of SSTs offers a tremendous opportunity for the use of samples archived in various SSTs.

Abstract 3969: Pediatric preclinical testing program (PPTP) evaluation of BMN 673, an inhibitor of poly-adp ribose polymerase (PARP), with temozolomide (TMZ)

Introduction: BMN 673 is a potent and selective inhibitor of PARP1/2. Inhibitors of PARP such as BMN 673 show clinical activity against cancers lacking homologous repair through mutations in BRCA1 and 2. PARP inhibitors are of particular interest for Ewing sarcoma (ES) given reports of ES cell lines being preferentially sensitive to PARP inhibitors. However, BMN 673 and other PARP inhibitors have shown limited single agent activity against Ewing sarcoma xenografts.

Methods: BMN 673 (10 nM) was evaluated in combination with TMZ and topotecan against the 23 cell lines of the PPTP in vitro panel using 96 hour exposure. For in vivo combination studies, two dose levels of BMN 673 (0.25 & 0.1 mg/kg BID x 5 days) given with TMZ [12 & 30 mg/kg/day x 5 days, respectively] were evaluated against ES xenografts. The combination regimen using the lower dose (LD) of TMZ and higher dose of BMN 673 was studied against other histotypes. Standard PPTP measures of in vivo antitumor activity were employed to assess response.

Results: BMN 673 markedly potentiated TMZ activity in vitro, with the TMZ rIC50 reduced by a median of 10-fold for PPTP cell lines, with ES cell lines showing a median 50-fold reduction. BMN 673 potentiated topotecan to a lesser degree (median 2.8-fold reduction in rIC50), with no differential sensitivity by histotype.

In vivo, 10 ES xenografts showed little or no response to 5 days of treatment with single agent TMZ (30 mg/kg) or BMN 673 (0.25 mg/kg BID), but 8 of 10 showed complete responses (CR) or maintained CR (MCR) to BMN 673 and TMZ (LD), and 5 of 10 showed CR or MCR to BMN 673 and higher-dose TMZ. The 10 ES xenografts could be separated into 2 groups based on duration of response to the combinations, with 5 showing delayed growth or brief objective responses (median time to event ≤ 30 days), and with the other 5 showing prolonged time to regrowth (median &gt; 77 days). Among 5 neuroblastoma xenografts, all showed significant treatment effects to BMN 673 plus TMZ(LD), with 1 achieving CR. Among 4 osteosarcoma xenografts, each showed significant tumor growth delay, but no objective responses were noted. Among 3 glioblastoma xenografts, 2 of 3 achieved maintained CRs (MCR) to the BMN 673 plus TMZ(LD) combination. Excessive toxicity was observed for ALL xenografts in NOD-SCID mice treated with the combination.

Conclusions: While BMN 673 shows limited single agent activity against PPTP solid tumor and ALL models with responses limited to models also highly sensitive to cisplatin, the BMN 673 plus TMZ(LD) combination shows dramatic activity for a subset of Ewing sarcoma xenografts and for selected additional models. Based on these results a pediatric phase 1 trial of BMN 673 plus TMZ with a phase 2 expansion for Ewing sarcoma is proceeding. Efforts are ongoing to relate genomic alterations identified through exome sequencing to responsiveness of ES xenografts to BMN 673 plus TMZ. (Supported by NO1-CM-42216)

Citation Format: Malcolm Smith, Min Kang, Patrick Reynolds, Richard Gorlick, Anders Kolb, John Maris, Richard Lock, Hernan Carol, Stephen Keir, Catherine Billups, Raushan Kurmasheva, Peter Houghton. Pediatric preclinical testing program (PPTP) evaluation of BMN 673, an inhibitor of poly-adp ribose polymerase (PARP), with temozolomide (TMZ). [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 3969. doi:10.1158/1538-7445.AM2014-3969

Abstract 5605: Spectral karyotyping characterization of ovarian adenocarcinomas and corresponding cell lines and xenografts

Ovarian cancer is the 9th leading cancer and the 5th cause of cancer deaths in women in the USA. To understand tumor biology, identify oncogenic driver pathways and verify response to drugs, numerous in vitro (cell lines) and in vivo (xenograft in mouse) models have been developed and extensively used. In this study, we aimed to cytogenetically characterize ovarian carcinomas and their respective in vitro and in vivo models to investigate how representative the models are of their originating source.

Ascitic fluid was collected from 10 women with previously untreated high grade serous papillary adenocarcinomas of the ovary that presented with malignant ascites (stage 3). Ascitic fluid was subjected to differential centrifugation and plating to enrich for the tumor cell population (TCP). The TCP cells were cultured and considered permanent cell lines (CLP) when grew continuously without evidence of a non-malignant component and could be recovered from cryopreservation. TCP cells were also inoculated intraperitoneally into athymic nude mice and tumors harvested and cryopreserved (XCP). Eight pairs of TCP and CLP and two triplets of TCP, CLP and XCP specimens were characterized by spectral karyotyping (SKY), for a total of 22 specimens.

Highly rearranged karyotypes were detected in all specimens. All matched pairs and triplets were obviously related, sharing most of the structural (SA) and numerical (NA) abnormalities identified. Numerous examples of evolution from simple to complex chromosomal rearrangements and of multiple rearrangements originating from a single breakpoint were detected. For 9 patients, TCP and CLP specimens had the same ploidy level (near-2n in 4, near-3n in 3 and near 4n in 2); for one patient, the ploidy changed from near-2n (TCP) to near-4n (CLP). The 2 xenografts had same ploidy as their matched TCP and CLP specimens. In individual analyses, specific SA accounted for &lt;10% of total SA in 8 specimens, for 10-30% in 8 and for &gt;30% in 6. Specific NA accounted for &lt;10% of total NA in 13 specimens, for 10-30% in 6 and for &gt;30% in 3. In the TCP-CLP analyses, 3 pairs were very similar, differing by &lt;10% of specific abnormalities; 5 pairs differed by 10-30% and 2 pairs by &gt;30%. Higher frequency of abnormalities was detected in the TCP specimen for 4 pairs, and in the CLP for 3 pairs. One xenograft was very similar to both TCP and CLP, while the other was closer to the CLP.

In conclusion, the ovarian adenocarcinomas were highly rearranged chromosomally and highly heterogeneous. In vitro (CLP) and in vivo (XCP) models maintained a core of the TCP's SA and NA but also displayed unique events, quantitatively and qualitatively variable in distinct tumors, indicating evidence of ex vivo tumor cell selection or progression events. These findings have implications for using established tumor models in research, as well as for potentially identifying the driver rearrangements in specific tumors.

Citation Format: Marileila Varella-Garcia, Isabel M. Bernal, Sakshi Mahale, Evelyn M. Musselwhite, Victor Stastny, Mahboubeh Papari-Zareei, Jayanthi Lea, Tito Woodburn, Patrick Reynolds, Adi F. Gazdar. Spectral karyotyping characterization of ovarian adenocarcinomas and corresponding cell lines and xenografts. [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 5605. doi:10.1158/1538-7445.AM2014-5605

Polycyclic aromatic hydrocarbons in residential dust and risk of childhood acute lymphoblastic leukemia

Several polycyclic aromatic hydrocarbons (PAHs) are known or probable human carcinogens. We evaluated the relationship between PAH exposure and risk of childhood acute lymphoblastic leukemia (ALL) using concentrations in residential dust as an exposure indicator. We conducted a population-based case-control study (251 ALL cases, 306 birth-certificate controls) in Northern and Central California from 2001 to 2007. We collected residential dust using a high volume small surface sampler (HVS3) (n=185 cases, 212 controls) or by sampling from participants' household vacuum cleaners (n=66 cases, 94 controls). We evaluated log-transformed concentrations of 9 individual PAHs, the summed PAHs, and the summed PAHs weighted by their carcinogenic potency (the toxic equivalence). We calculated odds ratios (ORs) and 95% confidence intervals (CI) using logistic regression adjusting for demographic characteristics and duration between diagnosis/reference date and dust collection. Among participants with HVS3 dust, risk of ALL was not associated with increasing concentration of any PAHs based on OR perln(ng/g). Among participants with vacuum dust, we observed positive associations between ALL risk and increasing concentrations of benzo[a]pyrene (OR perln[ng/g]=1.42, 95% CI=0.95, 2.12), dibenzo[a,h]anthracene (OR=1.98, 95% CI=1.11, 3.55), benzo[k]fluoranthene (OR=1.71, 95% CI=0.91, 3.22), indeno[1,2,3-cd]pyrene (OR=1.81, 95% CI=1.04, 3.16), and the toxic equivalence (OR=2.35, 95% CI=1.18, 4.69). The increased ALL risk among participants with vacuum dust suggests that PAH exposure may increase the risk of childhood ALL; however, reasons for the different results based on HVS3 dust samples deserve further study.

A midas plugin to enable construction of reproducible web-based image processing pipelines

Image processing is an important quantitative technique for neuroscience researchers, but difficult for those who lack experience in the field. In this paper we present a web-based platform that allows an expert to create a brain image processing pipeline, enabling execution of that pipeline even by those biomedical researchers with limited image processing knowledge. These tools are implemented as a plugin for Midas, an open-source toolkit for creating web based scientific data storage and processing platforms. Using this plugin, an image processing expert can construct a pipeline, create a web-based User Interface, manage jobs, and visualize intermediate results. Pipelines are executed on a grid computing platform using BatchMake and HTCondor. This represents a new capability for biomedical researchers and offers an innovative platform for scientific collaboration. Current tools work well, but can be inaccessible for those lacking image processing expertise. Using this plugin, researchers in collaboration with image processing experts can create workflows with reasonable default settings and streamlined user interfaces, and data can be processed easily from a lab environment without the need for a powerful desktop computer. This platform allows simplified troubleshooting, centralized maintenance, and easy data sharing with collaborators. These capabilities enable reproducible science by sharing datasets and processing pipelines between collaborators. In this paper, we present a description of this innovative Midas plugin, along with results obtained from building and executing several ITK based image processing workflows for diffusion weighted MRI (DW MRI) of rodent brain images, as well as recommendations for building automated image processing pipelines. Although the particular image processing pipelines developed were focused on rodent brain MRI, the presented plugin can be used to support any executable or script-based pipeline.

Abstract C206: Pediatric Preclinical Testing Program (PPTP) evaluation of BMN 673, an inhibitor of Poly-ADP Ribose Polymerase (PARP), alone and with Temozolomide (TMZ)

Introduction: BMN 673 is a potent and selective inhibitor of PARP1/2. Inhibitors of PARP such as BMN 673 show clinical activity against cancers lacking homologous repair through mutations in BRCA1 and 2. For Ewing sarcoma (ES), the EWS/FLI1 chimeric transcription factor increases PARP expression, and PARP appears to facilitate EWS/FLI1 function. Two reports have indicated that ES cell lines are more sensitive to PARP inhibitors than most other cell lines.

Methods: BMN 673 was evaluated as a single agent and in combination with TMZ against the 23 cell lines of the PPTP in vitro panel using 96 hour exposure. In single-agent studies, daily oral BMN 673 administration was tested against the PPTP solid tumor xenografts (SCID mice) and acute lymphoblastic leukemia (ALL; NOD-SCID mice) panels using a dose of 0.16 mg/kg BID x 5 and 0.33 mg/kg QD on weekends for up to 28 days. In combination studies, two dose levels of BMN 673 (0.25 & 0.1 mg/kg BID x 5 days) given with TMZ (12 & 30 mg/kg/day x 5 days, respectively) were evaluated against ES xenografts. Standard PPTP measures of in vivo antitumor activity were employed to assess response.

Results: The median relative IC50 (rIC50) for BMN 673 against the PPTP cell lines was 28 nM, with a range from 4 nM to &gt;1000 nM. There was a trend for lower rIC50 values for the ES cell line panel. In combination with a fixed concentration of BMN 673 (10 nM), the TMZ rIC50 was markedly reduced for some PPTP cell lines, with ES cell lines showing up to a 60-fold reduction. In vivo, BMN 673 was well tolerated with only a 1.9% toxicity rate in the treated groups. BMN 673 induced significant improvements in event-free survival (EFS) distribution compared to control in 18 of 35 (51%) of the evaluable solid tumor xenografts, but in 0 of 8 ALL models. Only 2 of 34 (6%) evaluable solid tumor xenografts and no ALL models showed EFS T/C values &gt; 2. Complete responses (CR) were observed for a Wilms tumor and a medulloblastoma model.

BMN 673 in combination with TMZ induced CRs that were maintained through week 12 for 2 of 4 ES xenografts (TMZ dosed at either 12 or 30 mg/kg/day). Among an additional 6 ES xenografts that have recently initiated testing, 3 have ongoing CRs to the combination at Weeks 4 to 5. None of the ES xenografts responded to 5 days of treatment with single agent TMZ (30 mg/kg) or BMN 673 (0.5 mg/kg/day).

Conclusions: Single agent BMN 673 shows limited activity against the PPTP solid tumor and ALL models, with no single agent activity against ES xenografts in vivo, despite ES cell lines demonstrating differential sensitivity in vitro. BMN 673 as a single agent induced CRs in 2 of 43 models, both of which are also highly responsive to cisplatin. Dramatic activity for the BMN 673 plus TMZ combination was observed for 5 of 10 ES models, with maintained CRs noted in vivo at TMZ doses as low as 12 mg/kg. Based on these results a pediatric phase 1 trial of BMN 673 plus TMZ is planned. (Supported by NO1-CM-42216)

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):C206.

Citation Format: Malcolm Smith, Min Kang, Patrick Reynolds, Richard Gorlick, Anders Kolb, John Maris, Richard Lock, Hernan Carol, Stephen Keir, Catherine Billups, Raushan Kurmasheva, Peter Houghton. Pediatric Preclinical Testing Program (PPTP) evaluation of BMN 673, an inhibitor of Poly-ADP Ribose Polymerase (PARP), alone and with Temozolomide (TMZ). [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr C206.

Fully automated rodent brain MR image processing pipeline on a Midas server: from acquired images to region-based statistics

Magnetic resonance imaging (MRI) of rodent brains enables study of the development and the integrity of the brain under certain conditions (alcohol, drugs etc.). However, these images are difficult to analyze for biomedical researchers with limited image processing experience. In this paper we present an image processing pipeline running on a Midas server, a web-based data storage system. It is composed of the following steps: rigid registration, skull-stripping, average computation, average parcellation, parcellation propagation to individual subjects, and computation of region-based statistics on each image. The pipeline is easy to configure and requires very little image processing knowledge. We present results obtained by processing a data set using this pipeline and demonstrate how this pipeline can be used to find differences between populations.

Opinion & special articles: the lost resident: why resident physicians still need mentoring

Mentoring is deeply rooted in medical practice. More than just a role model, a mentor is invested in the development of the mentee, providing personal and professional support, guidance, and the means for advancement. Mentoring is vital at all levels of medical training and plays an important role in the development of academicians. Increasing clinical demands, the competitive research environment, numerous administrative pressures, and the relative undervaluing of mentoring for faculty promotion have created challenges to resident mentoring. A greater emphasis on promoting mentoring opportunities for residents is needed at many levels.

ERBB4 confers metastatic capacity in Ewing sarcoma

Metastatic spread is the single-most powerful predictor of poor outcome in Ewing sarcoma (ES). Therefore targeting pathways that drive metastasis has tremendous potential to reduce the burden of disease in ES. We previously showed that activation of the ERBB4 tyrosine kinase suppresses anoikis, or detachment-induced cell death, and induces chemoresistance in ES cell lines in vitro. We now show that ERBB4 is transcriptionally overexpressed in ES cell lines derived from chemoresistant or metastatic ES tumours. ERBB4 activates the PI3K-Akt cascade and focal adhesion kinase (FAK), and both pathways contribute to ERBB4-mediated activation of the Rac1 GTPase in vitro and in vivo. ERBB4 augments tumour invasion and metastasis in vivo, and these effects are blocked by ERBB4 knockdown. ERBB4 expression correlates significantly with reduced disease-free survival, and increased expression is observed in metastatic compared to primary patient-matched ES biopsies. Our findings identify a novel ERBB4-PI3K-Akt-FAK-Rac1 pathway associated with aggressive disease in ES. These results predict that therapeutic targeting of ERBB4, alone or in combination with cytotoxic agents, may suppress the metastatic phenotype in ES.

Abstract 580: Increased DNA repair capacities and p53/MDM2 pathway aberrations hallmark neuroblastoma cell lines with the alternative lengthening of telomeres (ALT) phenotype

Introduction: Neuroblastoma (NB) is a malignant pediatric tumor of the sympathetic nervous system. Approximately 10-20% of neuroblastoma tumors maintain telomere length by activating a telomerase-independent alternative lengthening of telomeres (ALT) mechanism, and that these tumors are associated with high-stage disease, and a poor prognosis.

Methods: mRNA expression of TERT (the catalytic component of telomerase) and TERC (RNA template), determination of MYCN copy number, and telomerase activity (TA) was measured by RT-PCR. Telomere content (TC) and C-Circle (CC) content was assayed by quantitative PCR, p53 function was assessed by quantifying induction of p21 protein by flow cytometry after irradiation. Expression profiling was carried out with custom-designed Taq-Man Low Density Arrays (TLDAs) (ABI) that quantified expression of 61 DNA-repair genes in a panel of 12 NB cell lines, 4 ALT and 8 telomerase-positive. Of the telomerase-positive lines, 2 were drug-sensitive, 6 multi-drug resistant. Cell line identities were confirmed using short tandem repeat (STR) genotyping. Response to cytotoxic drugs was assessed using the DIMSCAN fluorescence imaging system. ATRX protein expression was measured with immunoblots.

Results: From a panel of 40 human NB cell lines we identified 4 ALT NB lines, LA-N-6, SK-N-FI, CHLA-90, and COG-N-291, that had elevated TC &gt; 2-fold that of TA+ NB cell lines (p&lt;.005), two of which demonstrated telomere repeat C-circles, and all lacked MYCN genomic amplification. All 4 ALT+ NB cell lines maintain telomere length with significantly low levels of telomerase activity (p&lt;.005) and mRNA expression of TERT relative to telomerase-positive NB cell lines; 3 of the 4 ALT lines lacked p53 function and LA-N-6, the sole p53-functional ALT line carries a homozygous deletion of p14(ARF). ALT lines had a significant increase (p&lt;.05) in the expression of 28 of the 61 DNA-repair genes analyzed by TLDA relative to telomerase-positive lines (including those that manifest multidrug resistance); 10 of these genes are involved in the nucleotide excision repair pathway. All 4 ALT cell lines showed a high degree of multi-drug resistance, with the mean concentration cytotoxic to 90% of the ALT cells (IC90) being higher than clinically achievable plasma levels for melphalan (2-fold), etoposide (4-fold), topotecan (5-fold), and carboplatin (4-fold). CHLA-90 had undetectable ATRX protein levels, whereas the other three ALT+ NB cell lines expressed ATRX.

Conclusions: ALT-based telomere maintenance in NB cell lines was associated with loss of p53 function, increased expression of DNA-repair genes, and resistance to DNA-damaging chemotherapy. Loss of ATRX expression is not essential for ALT to develop in NB. Novel, p53-independent therapies should be considered to treat neuroblastomas harboring the ALT phenotype.

Citation Format: Ahsan Farooqi, Ashly Hindle, Balakrishna Koneru, Jerry Shay, Patrick Reynolds. Increased DNA repair capacities and p53/MDM2 pathway aberrations hallmark neuroblastoma cell lines with the alternative lengthening of telomeres (ALT) phenotype. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 580. doi:10.1158/1538-7445.AM2013-580

Abstract 2758: Pediatric preclinical testing program (PPTP) stage 1 evaluation of MLN0128, a potent TOR kinase inhibitor

Introduction: The PI3K-TORC1 pathway links extracellular (growth factors) and intracellular (nutrient sensing) to cell cycle progression and proliferation. This pathway is dysregulated in many adult cancers, but less is known regarding childhood malignancies. MLN0128 is a novel orally-available small molecule inhibitor of both the TORC1 and TORC2 complexes, key components of the PI3K/mTOR signaling pathway.

Methods: MLN0128 was evaluated against the 23 cell lines of the PPTP in vitro panel using 96 hour exposure at concentrations from 0.1 nM to 1.0 μM. MLN0128 was tested against the PPTP solid tumor xenografts (SCID mice) and acute lymphoblastic leukemia (ALL; NOD-SCID mice) panels using a dose of 1 mg/kg administered by the P.O. route daily for 21 days.

Results: In vitro the median relative IC50 value for the PPTP cell lines was 19 nM, with a range from 2 nM to 102 nM. There was a trend for lower median rIC50 values for the rhabdomyosarcoma and Ewing sarcoma cell line panels (8 nM and 5 nM, respectively). The median rIC50 value for the ALL cell lines (68 nM) was significantly greater than that for the non-ALL cell lines.

In vivo MLN0128 was well tolerated, with only a 1.4% toxicity rate in the treated groups, compared to a 0.3% toxicity rate in control animals. All 38 tested xenograft models were considered evaluable for efficacy. MLN0128 induced significant differences in EFS distribution compared to control in 24 of 31 (77%) of the evaluable solid tumor xenografts, but did not induce significant differences in EFS distribution in any of the 7 evaluable ALL xenografts. MLN0128 induced tumor growth inhibition meeting criteria for intermediate EFS T/C activity (EFS T/C &gt; 2) in 6 of 30 (20%) evaluable solid tumor xenografts. Intermediate activity for the EFS T/C metric occurred in the rhabdoid tumor panel (2 of 3) and in single xenografts in four other panels. Objective responses were not observed for the solid tumor or for the ALL xenograft panels. Pharmacodynamic studies to determine TOR inhibition are planned.

Conclusions: The activity observed for MLN0128 against the PPTP preclinical models is similar to that previously reported by the PPTP for another TOR kinase inhibitor (Houghton PJ, et al. Pediatr Blood Cancer. 58:191-9, 2012). When combined with PPTP results reported for PI3K and AKT inhibitors (Reynolds CP, et al. Pediatr Blood Cancer. 2012. Epub 2012/09/25 and Gorlick R, et al. Pediatr Blood Cancer. 59:518-24, 2012), the available data suggest that kinase inhibitors targeting the PI3K pathway produce limited single agent activity for the tumor types represented by the PPTP models. (Supported by award NO1-CM-42216 from the NCI).

Citation Format: Peter Houghton, Min H. Kang, Patrick Reynolds, Richard Lock, Hernan Carol, Richard Gorlick, Anders Kolb, John Maris, Stephen Keir, Catherine Billups, Raushan Kurmasheva, Malcolm Smith. Pediatric preclinical testing program (PPTP) stage 1 evaluation of MLN0128, a potent TOR kinase inhibitor. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2758. doi:10.1158/1538-7445.AM2013-2758

Abstract LB-354: Pediatric Preclinical Testing Program (PPTP) stage 1 evaluation of the XPO1/CRM1 inhibitor KPT-330

Introduction: KPT-330 is an oral Selective Inhibitor of Nuclear Export (SINE) that binds covalently to XPO1 at Cys528 resulting in its irreversible inactivation. The nuclear export of over 200 proteins with specific nuclear export sequences (NES) is mediated via XPO1. Amongst the client proteins are many tumor suppressor and growth regulatory proteins (e.g., FOXO, IκB, pRb, p53, p73, p21, and p27).

Methods: KPT-330 was tested against the PPTP's in vitro cell line panel at concentrations ranging from 1.0 nM to 10.0 μM using the PPTP's standard 96 hour exposure period. It was tested against the PPTP solid tumor xenografts using a dose of 10 mg/kg administered by the oral route thrice weekly (M-W-F) for 4 weeks with a total treatment/observation period of 6 weeks.

Results: The median relative IC50 (rIC50) value for the PPTP cell lines was 125 nM, with a range from 13 nM to greater than 10 μM. There were no significant differences in rIC50 values by histotype, although there was a trend for greater sensitivity for the Ewing sarcoma cell lines (median rIC50 = 57 nM) and lesser sensitvity for the neuroblastoma cell lines (median rIC50 = 235 nM). Most cell lines showed Relative I/O% values between -75% and -100%, consistent with a prominent cytotoxic effect for KPT-330.

KPT-330 was well tolerated in vivo. It induced significant differences in EFS distribution compared to control in 29 of 37 (78%) solid tumor xenografts and in 5 of 8 (63%) ALL xenografts. For those xenografts with a significant difference in EFS distribution between treated and control groups, an EFS T/C value of greater than 2.0 indicates a substantial agent effect in slowing tumor growth. KPT-330 induced this level of effect in 11 of 32 (34%) solid tumor xenografts, most frequently for the Wilms tumor (2 of 3) and the Ewing sarcoma (4 of 5) panels. Objective responses were observed in 3 of 38 (4%) solid tumor xenografts, including a maintained complete response (MCR) for a Wilms tumor xenograft, a CR for a medulloblastoma xenograft, and a CR for a slow-growing ependymoma xenograft. For the ALL panel, 2 of 8 (25%) xenografts achieved either CR (ALL-8, T-cell ALL) or MCR (ALL-19, B-precursor ALL).

Conclusions: KPT-330 shows potent in vitro activity against many PPTP cell lines, consistent with the activation of multiple tumor suppressor proteins across diverse tumor genotypes. KPT-330 shows tumor regressing activity against selected PPTP solid tumor and ALL xenografts, and shows tumor growth inhibition for a larger number of models. Defining the relationship between KPT-330 systemic exposure in mice and humans will be important in assessing the clinical relevance of the PPTP in vivo results. Planned PD testing may identify biomarkers associated with response of pediatric preclinical models to KPT-330. KPT-330 is in phase 1 clinical trials in adults with advanced solid or hematological malignancies (NCT01607905 and NCT01607892). (Supported by NCI NO1-CM-42216)

Citation Format: Peter Houghton, Min Kang, Patrick Reynolds, Richard Gorlick, Anders Kolb, John Maris, Stephen Keir, Hernan Carol, Richard Lock, Catherine Billups, Raushan Kurmasheva, Yosef Landesman, Sharon Shacham, Michael Kauffman, Malcolm A. Smith. Pediatric Preclinical Testing Program (PPTP) stage 1 evaluation of the XPO1/CRM1 inhibitor KPT-330. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-354. doi:10.1158/1538-7445.AM2013-LB-354

Discovering online learning barriers: survey of health educational stakeholders in dentistry

OBJECTIVES

Given the exponential explosion of online learning tools and the challenge to harness their influence in dental education, there is a need to determine the current status of online learning tools being adopted at dental schools, the barriers that thwart the potential of adopting these and to capture this information from each of the various stakeholders involved in dental online learning (administrators, instructors, students and software/hardware technicians). The aims of this exploratory study are threefold: first, to understand which online learning tools are currently being adopted at dental schools; second, to determine the barriers in adopting online learning in dental education; and third, to identify a way of better preparing stakeholders in their quest to encourage others at their institutions to adopt online learning tools.

METHODS

Seventy-two participants representing eight countries and 13 stakeholder groups in dentistry were invited to complete the online Survey of Barriers in Online Learning Education in Health Professional Schools. The survey was created for this study but generic to all healthcare education domains. Twenty participants completed the survey.

RESULTS

demonstrated that many online learning tools are being successfully adopted at dental schools, but computer-based assessment tools are the least successful. Added to this are challenges of support and resources for online learning tools. Participants offered suggestions of creating a blended (online and face-to-face) tutorial aimed at assisting stakeholders to help their dental schools in adopting online learning tools

CONCLUSION

The information from this study is essential in helping us to better prepare the next generation of dental providers in terms of adopting online learning tools. This paper will not only provide strategies of how best to proceed, but also inspire participants with the necessary tools to move forward as they assist their clients with adopting and sustaining online learning tools and models.

Systematic stroke prevention

PURPOSE OF REVIEW

: This review summarizes the systematic approaches that can be used to optimize secondary stroke prevention. Systematic secondary stroke prevention involves not only prescribing stroke patients the appropriate medications to manage risk factors, but also optimizing the effectiveness of those drugs by focusing on medication adherence. Medication adherence is defined as the extent to which patients take their medications as prescribed by their providers.

RECENT FINDINGS

: Many potential barriers to adherence exist, including relationships among patient, provider, and the health system. Medication reconciliation at discharge and early follow-up are steps that may increase medication adherence, decrease medication errors, and improve the transition to home. In addition, inclusion of the primary provider or stroke specialist in decisions regarding the management of antithrombotic therapy for procedures is important, as discontinuing these medications is often associated with recurrent ischemic events.

SUMMARY

: Prevention of recurrent stroke should be a priority for patients, caregivers, providers, and health systems. Medication-taking behavior should be considered from all of these perspectives in order to optimize adherence.

Abstract LB-318: Pediatric Preclinical Testing Program (PPTP) evaluation of the JAK inhibitor AZD1480

Background: AZD1480 is a potent, competitive small molecule inhibitor of JAK1/2 kinase that has entered clinical evaluation. JAK inhibition is of particular pediatric interest given the activating JAK1/2 mutations observed in a subset of pediatric ALL cases. The activity of AZD1480 was evaluated against the PPTP's in vitro and in vivo panels. Methods: AZD1480 (provided by AstraZeneca) was tested in vitro at concentrations from 1.0 nM to 10.0 µM. It was evaluated against solid tumor xenografts at 60 mg/kg administered by oral gavage daily x 5 for 3 weeks, with a total treatment and observation period of 6 weeks. For the ALL panel (using NOD-SCID mice), the maximum tolerated dose was lower, and a twice daily schedule was utilized: 10 mg/kg BID (with a single daily dose of 15 mg/kg on weekends). Standard PPTP measures of in vivo antitumor activity were employed to assess response to AZD1480. Results: The median relative IC50 (rIC50) for AZD1480 against the PPTP cell lines was 1.5 µM, with a range from 0.3 µM to 5.9 µM. AZD1480 induced significant differences in EFS distribution compared to control in 25 of 27 (93%) evaluable solid tumor xenografts. AZD1480 induced tumor growth inhibition meeting criteria for intermediate or high EFS T/C activity in 11 of 26 (42%) solid tumor xenografts evaluable for this measure. Both Wilms tumor xenografts tested showed EFS T/C &gt; 2, as did 2 of 4 GBM xenografts and 2 of 4 neuroblastoma xenografts. An objective response was observed for 1 solid tumor xenograft, a Wilms tumor xenograft KT-10 that achieved a maintained complete response (MCR). Many solid tumor xenografts show phospho-STAT3 expression, but this marker showed no discernible relationship with response to AZD1480. For the ALL panel, 5 JAK mutated xenografts (3 JAK2 and 2 JAK1) were selected for testing to determine whether AZD1480 shows high activity in models in which the JAK-STAT pathway is activated by mutation. Additionally, 4 non-JAK mutated xenografts were evaluated. Models with JAK mutations show phospho-STAT5 as evidence of JAK-STAT signaling. However, the only ALL xenograft with EFS T/C &gt; 2 was a JAK2 mutant (R867Q) xenograft, TGT-20, and no models showed objective responses (PR or CR). Conclusions: AZD1480 showed tumor growth inhibitory activity against most of the solid tumor xenografts, and induced an objective response (an MCR) in a single Wilms tumor xenograft. Genomic sequencing is being undertaken to determine whether this xenograft has a genomic alteration(s) in a JAK family kinase or another kinase that may explain its favorable response. No objective responses were noted for the ALL panel, even among xenografts with JAK mutations. Our results suggest that inhibition of JAK signaling alone may not be sufficient for clinical activity against JAK-mutated ALL. (Supported by NCI NO1CM42216)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-318. doi:1538-7445.AM2012-LB-318

Abstract LB-317: Pediatric Preclinical Testing Program (PPTP) evaluation of volasertib (BI 6727), a Polo-like kinase (PLK) inhibitor

Background: Volasertib is a first in class, selective and potent cell cycle kinase inhibitor that induces mitotic arrest and apoptosis by targeting PLK. Genomic screens have identified PLK1 as a potential therapeutic target for several pediatric cancers, including rhabdomyosarcoma and neuroblastoma. Methods: Volasertib (provided by Boehringer Ingelheim) was tested in vitro at concentrations from 0.1 nM to 1.0 µM. Volasertib was tested against the PPTP solid tumor xenografts using a dose of 30 mg/kg administered intravenously weekly x 3. For the ALL panel (using NOD-SCID mice), the MTD was 15 mg/kg, and this dose was used for efficacy testing. The total planned treatment period was 3 weeks with an additional 3 weeks observation. Two measures of antitumor activity were primarily used: 1) an objective response measure modeled after the clinical setting; and 2) a time to event (4-fold increase in tumor volume) measure based on the median event-free survival (EFS) of treated (T) and control (C) animals for each xenograft. Intermediate activity requires EFS T/C &gt; 2, with high activity additionally requiring regression at the end of the observation period. Results: The median relative IC50 (rIC50) value for the PPTP cell lines was 14.1 nM, with a range from 6.0 nM to 135 nM. The median rIC50 values were lowest for the ALL cell line panel compared to the remaining cell lines (11.9 versus 16.0 nM, respectively), but this difference was not significant, and overall there were no differences in rIC50 by histotype. Against the PPTP in vivo panels volasertib induced significant differences in EFS distribution compared to control in 19 of 32 (59%) evaluable solid tumor xenografts and in 2 of 4 (50%) evaluable ALL xenografts. Volasertib induced tumor growth inhibition meeting criteria for intermediate EFS T/C activity in 11 of 30 (37%) evaluable solid tumor xenografts. Intermediate activity for the EFS T/C metric was most consistently observed in the neuroblastoma (4 of 6) and glioblastoma (2 of 3) panels. For the ALL panel, 2 of 4 (50%) xenografts met criteria for intermediate activity. Objective responses were observed for 4 of 32 solid tumor and 1 of 4 ALL xenografts. Two of 6 neuroblastoma xenografts demonstrated CRs, as did 1 of 3 glioblastoma and 1 of 5 rhabdomyosarcoma xenografts evaluable for this response measure. Conclusions: Volasertib showed low nanomolar in vitro potency against the PPTP cell lines with no histotype selectivity. Volasertib induced regressions in 5 of 36 evaluable PPTP xenografts with the neuroblastoma panel showing the most consistent pattern of responsiveness to volasertib. Given available pharmacokinetic data showing that mice tolerate higher systemic exposure to volasertib than humans, it is unlikely that the PPTP in vivo results are under-estimating the potential clinical activity of volasertib against the childhood cancer types evaluated here. (Supported by NCI NO1CM42216)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-317. doi:1538-7445.AM2012-LB-317

Birth characteristics and childhood carcinomas

Background:

Carcinomas in children are rare and have not been well studied.

Methods:

We conducted a population-based case–control study and examined associations between birth characteristics and childhood carcinomas diagnosed from 28 days to 14 years during 1980–2004 using pooled data from five states (NY, WA, MN, TX, and CA) that linked their birth and cancer registries. The pooled data set contained 57 966 controls and 475 carcinoma cases, including 159 thyroid and 126 malignant melanoma cases. We used unconditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs).

Results:

White compared with ‘other’ race was positively associated with melanoma (OR=3.22, 95% CI 1.33–8.33). Older maternal age increased the risk for melanoma (OR_{per 5-year age increase}=1.20, 95% CI 1.00–1.44), whereas paternal age increased the risk for any carcinoma (OR=1.10_{per 5-year age increase}, 95% CI 1.01–1.20) and thyroid carcinoma (OR_{per 5-year age increase}=1.16, 95% CI 1.01–1.33). Gestational age <37 vs 37–42 weeks increased the risk for thyroid carcinoma (OR=1.87, 95% CI 1.07–3.27). Plurality, birth weight, and birth order were not significantly associated with childhood carcinomas.

Conclusion:

This exploratory study indicates that some birth characteristics including older parental age and low gestational age may be related to childhood carcinoma aetiology.