Citations

Noonan syndrome (NS; MIM 163950) is an autosomal dominant disorder and a member of a family of developmental disorders termed “RASopathies,” which are caused mainly by gain-of-function mutations in genes encoding RAS/MAPK signaling pathway proteins. Whole exome sequencing (WES) and trio-based genomic triangulation of a 15-year-old female with a clinical diagnosis of NS and concomitant cardiac hypertrophy and her unaffected parents identified a de novo variant in MRAS -encoded RAS-related protein 3 as the cause of her disease. Mutation analysis using in silico mutation prediction tools and molecular dynamics simulations predicted the identified variant, p.Gly23Val-MRAS, to be damaging to normal protein function and adversely affect effector interaction regions and the GTP-binding site. Subsequent ectopic expression experiments revealed a 40-fold increase in MRAS activation for p.Gly23Val-MRAS compared with WT-MRAS. Additional biochemical assays demonstrated enhanced activation of both RAS/MAPK pathway signaling and downstream gene expression in cells expressing p.Gly23Val-MRAS. Mutational analysis of MRAS in a cohort of 109 unrelated patients with phenotype-positive/genotype-negative NS and cardiac hypertrophy yielded another patient with a sporadic de novo MRAS variant (p.Thr68Ile, c.203C>T). Herein, we describe the discovery of mutations in MRAS in patients with NS and cardiac hypertrophy, establishing MRAS as the newest NS with cardiac hypertrophy-susceptibility gene.

Abstract Purpose: Cyclin-dependent kinase (CDK) 4/6 drives cell proliferation in estrogen receptor–positive (ER+) breast cancer. This single-arm phase II neoadjuvant trial (NeoPalAna) assessed the antiproliferative activity of the CDK4/6 inhibitor palbociclib in primary breast cancer as a prelude to adjuvant studies. Experimental Design: Eligible patients with clinical stage II/III ER+/HER2− breast cancer received anastrozole 1 mg daily for 4 weeks (cycle 0; with goserelin if premenopausal), followed by adding palbociclib (125 mg daily on days 1–21) on cycle 1 day 1 (C1D1) for four 28-day cycles unless C1D15 Ki67 > 10%, in which case patients went off study due to inadequate response. Anastrozole was continued until surgery, which occurred 3 to 5 weeks after palbociclib exposure. Later patients received additional 10 to 12 days of palbociclib (Cycle 5) immediately before surgery. Serial biopsies at baseline, C1D1, C1D15, and surgery were analyzed for Ki67, gene expression, and mutation profiles. The primary endpoint was complete cell cycle arrest (CCCA: central Ki67 ≤ 2.7%). Results: Fifty patients enrolled. The CCCA rate was significantly higher after adding palbociclib to anastrozole (C1D15 87% vs. C1D1 26%, P < 0.001). Palbociclib enhanced cell-cycle control over anastrozole monotherapy regardless of luminal subtype (A vs. B) and PIK3CA status with activity observed across a broad range of clinicopathologic and mutation profiles. Ki67 recovery at surgery following palbociclib washout was suppressed by cycle 5 palbociclib. Resistance was associated with nonluminal subtypes and persistent E2F-target gene expression. Conclusions: Palbociclib is an active antiproliferative agent for early-stage breast cancer resistant to anastrozole; however, prolonged administration may be necessary to maintain its effect. Clin Cancer Res; 23(15); 4055–65. ©2017 AACR.

Abstract Clinical data indicate that certain regions within glioblastoma (GBM) have a relatively intact blood-brain barrier (BBB), but controversy surrounds whether associated heterogeneous delivery may limit efficacy for otherwise highly active drugs with poor brain distribution. In this study, the efficacy of molecularly targeted therapies was compared in relevant GBM patient-derived xenograft (PDX) models grown either as heterotopic or orthotopic tumors. The impact of further disrupting BBB integrity in non-responsive orthotopic tumors was evaluated by over-expressing vascular endothelial growth factor (VEGF) and measuring drug distribution by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI). The brain:plasma ratio for five targeted agents was determined by LC-MSMS and treatment efficacy was evaluated in target-relevant GBM PDX lines: erlotinib (brain:plasma = 0.02 ± 0.02; efficacy tested in GBM6), palbociclib (brain:plasma = 0.06; efficacy tested in GBM22), AZD1775 (brain:plasma = 0.05; efficacy tested in GBM22), SAR405838 (brain:plasma = 0.01 ± 0.003; efficacy tested in GBM108), and AZD4547 (brain:plasma = 0.045 ± 0.02; efficacy tested in GBM150). Each of these drugs was effective in relevant GBM PDX flank tumor models with a 27% to 218% prolongation in the median time to exceed their pre-specified endpoint compared to placebo treatment (p≤0.02 for each drug). In contrast, none of these drugs were effective in prolonging survival in the same target-relevant orthotopic tumor models (-6% to 8% extension in median survival; p>0.05 for each drug). Consistent with partial and heterogeneous disruption of the BBB, MALDI-MSI of erlotinib, AZD1775 or SAR405838 distribution within orthotopic tumors demonstrated highly heterogeneous drug levels with large regions within each tumor approaching the low drug levels observed within surrounding normal brain. To further evaluate whether heterogenous drug distribution in orthotopic tumors could account for poor treatment efficacy, GBM108 was transduced with lentiviral constructs encoding for VEGF or empty vector (EV). While both GBM108-sublines were readily detectable with gadolinium-enhanced magnetic resonance imaging (MRI), the GBM108-VEGF tumors had a significantly more disrupted BBB, as evidenced by a more uniform and intense distribution of a brain-impenetrant TexasRed-dextran vascular marker. Similarly, the distribution of SAR405838, measured by MALDI-MSI, was markedly higher and more uniform in the GBM108-VEGF tumors when compared to the GBM108-EV tumors. Enhanced delivery of SAR405838 into orthotopic GBM108-VEGF models translated into a marked enhancement in treatment efficacy in comparison to GBM108-EV with a median survival prolongation of 37 vs. 4 days, respectively (p=0.0055). Collectively, these data highlight the importance of testing novel therapeutic agents in orthotopic tumor models and suggest that limited brain penetration for many molecules may significantly limit their efficacy in brain tumors that have a partially intact BBB. In the face of continued failure to develop effective targeted agents for GBM, these in vivo results highlight the importance of re-evaluating the dogma in neuro-oncology that the BBB is fully disrupted in GBM and, therefore, drug delivery across the BBB is not a major factor limiting treatment efficacy. Citation Format: Jann N. Sarkaria, David Calligaris, Daniel Ma, Karen Parrish, Ann C. Mladek, Janice Laramy, Minjee Kim, Shuangling Zhang, Mark Schroeder, Brett L. Carlson, Katrina Bakken, Aaron Johnson, Nathalie Agar, William Elmquist. The critical importance of the blood-brain barrier in modulating the response to otherwise highly effective targeted therapies in patient-derived orthotopic glioblastoma xenografts. [abstract]. In: Proceedings of the AACR Special Conference: Patient-Derived Cancer Models: Present and Future Applications from Basic Science to the Clinic; Feb 11-14, 2016; New Orleans, LA. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(16_Suppl):Abstract nr B25.

Abstract This abstract was not presented at the symposium.

91 Background: Formal mechanisms to share data on quality remain immature in specialty palliative care. As the field grows, infrastructure that promotes collaboration among academic and community-based practice will be required to foster comparisons and benchmarking of data to inform areas for quality improvement. Further, such relationships will create a palliative care “quality improvement laboratory”, where proposed guidelines and best practices can be developed, implemented, and tested. Methods: We set out to bring together specialty palliative care practices with a shared vision for collaborative quality improvement. We modeled our approach after the Institute for Healthcare Improvement Breakthrough Series alongside our Rapid Learning Quality Improvement paradigm. We use a set of common data collection procedures, across an electronic point-of-care platform called Quality Data Collection Tool (QDACT), alongside a centralized data registry. Further, we meet and discuss challenges and issues, compare best practices, and brainstorm new projects through biweekly conference calls. Results: We have created a multi-institutional collaboration for quality assessment and improvement in specialty palliative care. Termed the Global Palliative Care Quality Alliance, we have brought together 11 academic and community organizations, both general and oncology-specific, across six states to study various areas of quality practice. Short-term, we will conduct rapid-cycling quality improvement projects addressing National Quality Forum domains for quality palliative care, including documentation of spiritual assessment and timely advance care planning. Long-term, we aim to study the link between quality measure adherence and outcomes and further align our initiatives with those of other large consortia, like the Palliative Care Research Cooperative and Palliative Care Quality Network. Conclusions: Collaborative quality improvement is needed in specialty palliative care across a national platform. Developing the infrastructure to perform standardized quality improvement is achievable across multiple palliative care settings.

65 Background: Cholangiocarcinoma (CC) accounts for approximately 3% of all gastrointestinal cancers and have a poor incident to mortality rate. The incidence in the United States (US) is 2,000-3,000 cases annually, with this rate steadily increasing during the last twenty years; this trend is not solely observed in US but also seen in Europe, Australia and Japan. The highest incidence is seen in Southeast Asia due to parasitic infection. CC presents many challenges to healthcare professionals due to the anatomic nature of CC (Lowe et al, 2015). The worldwide increase in incidence of CC is indication for the essential development of nursing practice guidelines underpinned by expert evidence and knowledge and regarding the key aspects of care. Methods: A collaboration of nursing professionals representing major cancer research institutions from around the country and the United Kingdom worked together to identify key aspects of care, the aim being to develop Clinical Nursing Practice Guidelines. The process included an exhaustive literature review using Pubmed, Uptodate, Medline, and CINAHL databases; submission of respective institutional practices; group consensus on guideline content, evidence-based scoring assignment and approval by the Cholangiocarcinoma Medical Advisory Board. Results: The guidelines developed include the care of the patient: (1) with external biliary drains and internal bile duct stents, (2) with intractable nausea and vomiting resulting from disease process, (3) with fatigue resulting from disease process, (4) undergoing chemotherapy, (5) undergoing photon radiation, (6) undergoing radiation on a clinical trial, and (7) preparing for liver transplantation. The purpose of the guidelines are to advance the scientific knowledge of the symptoms experienced, quality of life of patients with CCA, establish standards in patient care, and improve quality of care and satisfaction for patients diagnosed with CC. Conclusions: Creation of evidence-based guidelines will provide a springboard for expanded competent knowledge and a model to test for improvement in the care and quality of life of the patient with CC.

175 Background: Inactivity is common in breast cancer survivors and has been linked to poor outcomes. Few trials have tested physical activity (PA) interventions in young women with breast cancer, who may face unique PA barriers due to demands of jobs and young families. Methods: Young and Strong was a cluster-randomized study evaluating the effect of education interventions for young breast cancer survivors.Sites were randomized 1:1 to a young women’s intervention (YWI), focused on fertility and other issues facing young women, or to a physical activity intervention (PAI). At PAI sites, providers were instructed to discuss PA with patients, and participants were given materials to encourage PA. PA was measured with the modified Godin Leisure Score Index at baseline, and 3, 6, and 12 months. Medical records were reviewed to assess provider attention to PA. Changes in weekly min of PA were compared between the PAI and YWI groups using general estimating equations to evaluate clustered binary and Gaussian data. Results: 467 patients enrolled between 7/12 -12/13 across 54 sites. Median age at dx was 40yrs (range 22-45). At baseline, participants were moderately active. PA increased in both groups over time (Table); there was no significant difference in PA between groups at any time (all p > 0.1). Provider attention to PA was documented in 74% of participants on PAI and 61% on YWI (p = 0.15), and correlated with PA at 12 months (median 100 min/wk of PA in participants with provider attention to PA vs. 60 min/wk in those without, p = 0.016). Participants who reported reading all or most the PAI materials reported higher levels of PA vs. those who read less (78% vs. 64%, p = 0.05) Conclusions: Young breast cancer survivors assigned to a PA intervention did not increase PA more than those assigned to an intervention focused on young women’s issues. However, the higher levels of PA among women who engaged with the PAI materials and those whose oncology providers addressed PA suggests the importance of enhancing patient and provider engagement with healthy lifestyle information and recommendations. Clinical trial information: NCT01647607. [Table: see text]