Abstract P4-08-04: Navigating genomic landscape to find a PI3K-signaling algorithm for a rational combinatin in precision medicine

Background: Treatment of BC is conventionally based on the presence/absence of ER/PR or HER2 status of the primary tumor. We have enriched this approach by including major genetic and proteomic changes in tumors of individual patients in order to develop a better treatment-rationale based on an alteration driven signaling algorithm. Methods: Genomic and proteomic data from 75 BC patients seen in our center were retrospectively analyzed. Patients were re-biopsied after consultation and samples were characterized (IHC for ER, PR, and HER2; FFPE samples for genomic [Foundation Medicine] and proteomic analyses [Theranostics]). In vivo studies were conducted using xenograft models. Results: Although alterations of PIK3CA, PIK3R1, AKT, PTEN, MDM2, MDM4, TSC1, mTOR and RICTOR are most frequently observed in our patients, there is a distinct pattern of alteration(s) of the PI3K pathway genes in different subtypes of BC. A total of 76 genes were altered in 48 ER+BC patients. In 79% of ER+BC patients the above mentioned PI3K pathway genes were altered. Analyzing the set of alterations of genes in individual patients, we observed that within these 48 patients 25% exhibited alterations in more than one node of the pathway; the most common combination (alterations) being the amplification/mutation of PIK3CA with the amplification of MDM2/4 genes. The percentage of patients belonging to HER2+ & TNBC exhibiting similar alterations in the PI3K pathway genes were significantly lower (∼40%). Our previous in vivo studies demonstrated that GDC-0980 and BEZ235 enhanced the antitumor activity of ABT888 plus carboplatin in TNBC or trastuzumab in HER2+ BC respectively and blocked the growth of established xenograft tumors by 80% to 90% with a concomitant decrease in tumor Ki67, pS6RP and CD31. Mechanistically the action of the PI3K-mTOR pathway targeted drug(s) was tested using cell line based models of BC subtypes pertaining to their respective genomic alterations. A combination of a pan-PI3K pathway inhibitor, GDC-0941 or isoform-specific inhibitors along with AI, trastuzumab, or HRD inhibitors (PARP) blocked proliferative signals and enhanced apoptosis (cleaved caspase3) in ER+/PIK3CA mutated, HER2+/PIK3CA mutated or PTEN-null TNBC cells respectively as demonstrated by WB, flow cytometry, cell proliferation, viability and cytotoxicity assays. A recent study demonstrated that exposure to chemotherapy induced a phenotypic shift or cell state transition towards a transient CD44Hi/CD24Hi chemotherapy-tolerant state, leading to the activation of downstream non-receptor tyrosine kinase signaling towards an emerging adaptive resistance (Goldman et al., Nature Comm. 2015). Hence drug combination(s) are being tested for their effect on CD44/CD24 expression levels, results of which will be presented in the meeting. Conclusion: Plotting the genetic alterations from the patient on the signaling landscape will be useful in cracking the code leading to improved treatment options. Patient specific in-depth plotting of genetic alterations of the PI3K-mTOR pathway and the relevance of these alterations in the context of (1) mechanisms of PI3K-mTOR pathway targeted drugs and (2) cell signaling are critical in determining choice of drugs in BC subtypes.

Citation Format: Carlson JH, Krie A, Williams C, Sun Y, Lin X, Williams K, Klein J, Friedman L, De P, Dey N, Leyland-Jones B. Navigating genomic landscape to find a PI3K-signaling algorithm for a rational combinatin in precision medicine. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-08-04.

Abstract P5-03-14: MLN0128 regulates survival signaling by AKT and its downstream effectors in HER2+ breast cancer model

Evading apoptosis is considered to be a hallmark of cancers including breast cancer, since mutations in apoptotic regulators invariably accompany tumorigenesis. Chemotherapeutic agents induce apoptosis, and hence disruption of apoptosis during tumor progression may promote drug resistance. AKT is an apoptotic regulator that is activated in HER2+ breast tumor cells and promotes anti-HER2 therapy resistance in vitro. Nevertheless, how mTORC1/C2-AKT signaling disables apoptosis and its contribution to clinical drug resistance are not clear yet. Using HER2 amplified breast cancer cells [BT474 (HER2+/Trastuzumab-sensitive), BT474HerR (HER2+/Trastuzumab-resistant), HCC1954 and MDA-MB453 (both are HER2+/PIK3CA kinase domain mutated)], we show that mTORC1/C2 inhibitor; MLN0128 abrogates AKT (Ser473), Survivin and controls its downstream effectors of apoptotic signaling molecules (e.g. cleaved Caspase 3/9, cleaved PARP, MCL and BIM). MLN0128 also induces annexinV positive cells and regulates cellular proliferation (ON-TOP 3D colony formation and real-time proliferation assay). Additionally, increased cleaved Caspase 3 and decreased MCL1 expression were also observed following MLN0128 treatment in HER2+ xenograft model along with tumor growth inhibition. Our studies provide strong experimental evidence that high apoptotic signaling –specifically reduced MCL1 and increased cleaved-CASPASE3 expression expedite the response of targeted therapy that directly inhibits mTORC1/C2-AKT signaling.

Citation Format: De PK, Carlson JH, Sun Y, Lin X, Williams C, Dey N, Leyland-Jones BR. MLN0128 regulates survival signaling by AKT and its downstream effectors in HER2+ breast cancer model. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-03-14.

Abstract P2-05-09: Vascular mimicry in metastatic breast cancer patients: Molecular insight to vascular mimicry using in vitro and in vivo models

Background: Vascular Mimicry (VM) is an endothelium-independent matrix-embedded, blood-perfusion phenomenon exhibited by highly plastic and aggressive tumor cells in patients with solid tumors including breast. VM is characterized by PAS+ de novo formations of micro-vascular networks which are essentially CD31- and CD34-. VM is a micro-circulatory phenomenon which perfuses rapidly growing tumors, transporting fluid from leaky vessels and/or connects with the constituent endothelial-lined vasculature. One of the hallmarks of metastasis in BC is the heterogeneity observed between primary tumors and metastases (& among metastases) (Marino etal., 2013). Recently a model of BC heterogeneity revealed VM as a driver of metastasis which in turn has been associated with disease heterogeneity (Wagenblast etal., 2015). Aim: Since BC is an aggressive and heterogeneous disease and VM is associated with the aggressiveness / poor outcome in BC, we sought to understand the functional relationship of VM with metastasis. Method: Tumors from our BC patients and TMAs were stained for CD31/PAS and CD34/PAS to identify VM. Genomic and proteomic data from these patients were obtained from re-biopsied (after consultation) samples (IHC for ER, PR, and HER2; FFPE samples for genomic [Foundation Medicine] and proteomic [Theralink] analyses). Result: VM was identified in metastatic tumors from ER+ and TNBC patients as CD31-/PAS+ and CD34-/PAS+ structures in contrast to the CD31+/PAS+ and CD34+/PAS+ angiogenic compartment of the individual tumor(s). Metastatic tumors exhibiting VM were characterized by pathological features like metaplastic lesions, positive lympho-vascular invasion and were found to be poorly differentiated. Predominant genetic alterations in these patients included (1) PI3K-mTOR pathway genes, (2) p53 (R273P, D281V), (3) BRCA1 E1683* (for TNBC), (4) MYC amplification, (5) aurora kinase, (6) CCND1 & CDK4 amplifications and (7) loss of CDH1 exons1-3. Amplifications of cell surface TKIs/ligands included EGFR, FGFR and several FGFs. Proteomic data indicated an overexpression/activation of HER family (HER1/HER2/HER3), mTOR activation (p∼S2448), MEK1/2 activation (p∼S217-221) and JAK2 activation. In order study VM, we standardized VM formation both in 2D and 3D configurations in multiple BC cell lines which exhibited VM at differing times. The earliest response was observed around 2-3 hours in BT20, Hs578t and MDA-MB231. By 24 hours BT474, BT474HerR, SUM149, DKAT, MDA-MB231BR, Hs578t and MDA-MB468 cells demonstrated 2D VM. The BT20 cell line showed the most pronounced 3D-VM at 24 hours while MDA-MB468 was least sensitive to VM. Typical cord formation in HUVEC cells stained with hematoxylin and PAS were used for comparison. Using 2D and 3D models of VM we demonstrated the involvement of PI3K and Wnt-beta-catenin pathways in VM. Considering the involvement of VM in mediating the aggressive/metastatic nature of TNBC, we also tested VM in in vivo xenograft models using brain metastasic specific MDA-MB231BR cells, results of which will be presented in the meeting. Significance: To our knowledge this is the first report to identify genetic alterations and proteomic changes associated with VM in metastatic BC.

Citation Format: Dey N, Carlson JH, Lin X, Sun Y, Theel S, Krie A, Sulaiman RA, Williams C, De PK, Leyland-Jones BR. Vascular mimicry in metastatic breast cancer patients: Molecular insight to vascular mimicry using in vitro and in vivo models. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-05-09.

Childhood febrile illness and the risk of myopia in UK Biobank participants

Purpose

Historical reports suggest febrile illness during childhood is a risk factor for myopia. The establishment of the UK Biobank provided a unique opportunity to investigate this relationship.

Patients and methods

We studied a sample of UK Biobank participants of White ethnicity aged 40–69 years old who underwent autorefraction (N=91 592) and were classified as myopic (≤−0.75 Dioptres (D)), highly myopic (≤−6.00 D), or non-myopic (>−0.75 D). Self-reported age at diagnosis of past medical conditions was ascertained during an interview with a nurse at a Biobank assessment centre. Logistic regression analysis was used to calculate the odds ratio (OR) for myopia or high myopia associated with a diagnosis before age 17 years of each of nine febrile illnesses, after adjusting for potential confounders (age, sex, highest educational qualification, and birth order).

Results

Rubella, mumps, and pertussis were associated with myopia: rubella, OR=1.38, 95% CI: 1.03–1.85, P=0.030; mumps, OR=1.32, 95% CI: 1.07–1.64, P=0.010; and pertussis, OR=1.39, 95% CI 1.03–1.87, P=0.029. Measles, rubella, and pertussis were associated with high myopia: measles, OR=1.48, 95% CI: 1.07–2.07, P=0.019; rubella, OR=1.94, 95% CI: 1.12–3.35, P=0.017; and pertussis, OR=2.15, 95% CI: 1.24–3.71, P=0.006. The evidence did not support an interaction between education and febrile illness in explaining the above risks.

Conclusion

A history of childhood measles, rubella, or pertussis was associated with high myopia, whereas a history of childhood rubella, mumps, or pertussis was associated with any myopia. The reasons for these associations are unclear.

Idiopathic interstitial pneumonia in the ICU: an observational cohort

In the absence of a clearly identifiable cause, the prognosis of patients with interstitial lung disease is grim. This study describes our institutional experience in management of patients who are admitted to an ICU with respiratory insufficiency secondary to idiopathic interstitial pneumonia (IIP). This study was performed to obtain Australian data on patients admitted to an ICU with respiratory insufficiency secondary to IIP. This is a retrospective cohort study of patients with IIP who were admitted to the ICU between December 2007 and December 2013 at one of two university-affiliated academic hospitals in Newcastle, New South Wales. Thirty-six patients (69% male) were admitted to the ICU in respiratory insufficiency from IIP. The median age of the cohort was 71 (66 to 77) years. The median APACHE III score was 68 (56 to 97). Sixty-nine percent (25/36) of patients died in hospital. The median ICU and hospital lengths of stay were 6 (2 to 13.5) and 12 (4.8 to 18.3) days respectively. No significant difference was observed between admission characteristics and mortality. Patients admitted to ICU with respiratory failure secondary to IIP are aggressively investigated and treated, but still have a high mortality rate. Accurate predictors of mortality would be useful in offering aggressive treatment to patients who would benefit from it.

A scalable label-free approach to separate human pluripotent cells from differentiated derivatives

The broad capacity of pluripotent human embryonic stem cells (hESC) to grow and differentiate demands the development of rapid, scalable, and label-free methods to separate living cell populations for clinical and industrial applications. Here, we identify differences in cell stiffness, expressed as cell elastic modulus (CEM), for hESC versus mesenchymal progenitors, osteoblast-like derivatives, and fibroblasts using atomic force microscopy and data processing algorithms to characterize the stiffness of cell populations. Undifferentiated hESC exhibited a range of CEMs whose median was nearly three-fold lower than those of differentiated cells, information we exploited to develop a label-free separation device based on the principles of tangential flow filtration. To test the device's utility, we segregated hESC mixed with fibroblasts and hESC-mesenchymal progenitors induced to undergo osteogenic differentiation. The device permitted a throughput of 10(6)-10(7) cells per min and up to 50% removal of specific cell types per single pass. The level of enrichment and depletion of soft, pluripotent hESC in the respective channels was found to rise with increasing stiffness of the differentiating cells, suggesting CEM can serve as a major discriminator. Our results demonstrate the principle of a scalable, label-free, solution for separation of heterogeneous cell populations deriving from human pluripotent stem cells.

Bridging classical and quantum mechanics

Using a watt balance and a frequency comb, a mass-energy equivalence is derived. The watt balance compares mechanical power measured in terms of the meter, the second, and the kilogram to electrical power measured in terms of the volt and the ohm. A direct link between mechanical action and the Planck constant is established by the practical realization of the electrical units derived from the Josephson and the quantum Hall effects. By using frequency combs to measure velocities and acceleration of gravity, the unit of mass can be realized from a set of three defining constants: the Planck constant h, the speed of light c, and the hyperfine splitting frequency of 133Cs.

Phase I study of KW-2478, a novel Hsp90 inhibitor, in patients with B-cell malignancies

BACKGROUND

KW-2478 is a novel, non-ansamycin, non-purine heat-shock protein 90 (Hsp90) inhibitor.

METHODS

In this phase I, multicentre study, KW-2478 was administered intravenously over 1 h at doses ranging from 14 to 176 mg m(-2) once daily on days 1-5 of a 14-day cycle in a standard 3+3 design in 27 patients (22 with multiple myeloma and 5 with non-Hodgkin lymphoma). Patients enrolled had relapsed/refractory disease previously treated with ⩾2 regimens.

RESULTS

There were no dose-limiting toxicities, thus the maximum-tolerated dose was not reached. KW-2478 was well tolerated and did not manifest significant retinal or ocular toxicity. The most common treatment-related adverse events were diarrhoea (33.3%), fatigue (29.6%), headache (25.9%), hypertension (22.2%), nausea (14.8%), vomiting (7.4%), and dizziness (7.4%). Plasma concentrations peaked at the end of infusion and decayed in a biphasic manner with a terminal half-life of ∼6 h. Target inhibition was inferred from the increase in Hsp70 levels in peripheral blood mononuclear cells at doses ⩾71 mg m(-2). Twenty-four of 25 (96%) evaluable patients showed stable disease, with five being free of disease progression for ⩾6 months.

CONCLUSIONS

Preliminary clinical response data were encouraging and warrant further investigation of KW-2478 in combination regimens for relapsed/refractory B-cell malignancies.

A feasibility study of behavioural activation for depressive symptoms in adults with intellectual disabilities

BACKGROUND

Important work has been carried out adapting cognitive behavioural therapy for people with intellectual disabilities. However, there is a lack of alternative psychological therapies available for people with intellectual disabilities and emotional difficulties. Behavioural activation for depression is less reliant on verbal communication and focuses on increasing purposeful activity and reducing avoidance.

METHOD

This feasibility study involved the development and piloting of an adapted manual of behavioural activation for people with intellectual disabilities. The intervention consisted of 10-12 sessions and a key adaptation was that the therapist worked with the clients alongside a significant other in their life, either a paid carer or family member. Baseline, post-intervention (3 months after entering the study) and 6-month quantitative follow-up data were obtained. Primary outcome data were gathered, concerning depressive symptoms, participants' levels of activity and general well-being.

RESULTS

Twenty-three adults with intellectual disabilities with symptoms of depression were recruited from specialist health services. In terms of acceptability, the behavioural activation intervention was well received and only two individuals dropped out, with a further two lost to follow-up. The main measures of depression appeared to be sensitive to change. Pre- to post-intervention data showed a significant reduction in self-report of depressive symptoms with a strong effect size (r = 0.78), that was maintained at follow-up (r = 0.86). Positive change was also obtained for informant reports of depressive symptoms from pre- to post-intervention, with a strong effect size (r = 0.7). Once again, this positive change was maintained at follow-up (r = 0.72).

CONCLUSIONS

The study suggested that behavioural activation may be a feasible and worthwhile approach to tackling depression in people with intellectual disabilities. However, a randomised controlled trial would be required to establish its effectiveness, with more sensitive measurement of change in activity.

Biofilm formation is a risk factor for mortality in patients with Candida albicans bloodstream infection-Scotland, 2012-2013

Bloodstream infections caused by Candida species remain a significant cause of morbidity and mortality in hospitalized patients. Biofilm formation by Candida species is an important virulence factor for disease pathogenesis. A prospective analysis of patients with Candida bloodstream infection (n = 217) in Scotland (2012–2013) was performed to assess the risk factors associated with patient mortality, in particular the impact of biofilm formation. Candida bloodstream isolates (n = 280) and clinical records for 157 patients were collected through 11 different health boards across Scotland. Biofilm formation by clinical isolates was assessed in vitro with standard biomass assays. The role of biofilm phenotype on treatment efficacy was also evaluated in vitro by treating preformed biofilms with fixed concentrations of different classes of antifungal. Available mortality data for 134 patients showed that the 30-day candidaemia case mortality rate was 41%, with predisposing factors including patient age and catheter removal. Multivariate Cox regression survival analysis for 42 patients showed a significantly higher mortality rate for Candida albicans infection than for Candida glabrata infection. Biofilm-forming ability was significantly associated with C. albicans mortality (34 patients). Finally, in vitro antifungal sensitivity testing showed that low biofilm formers and high biofilm formers were differentially affected by azoles and echinocandins, but not by polyenes. This study provides further evidence that the biofilm phenotype represents a significant clinical entity, and that isolates with this phenotype differentially respond to antifungal therapy in vitro. Collectively, these findings show that greater clinical understanding is required with respect to Candida biofilm infections, and the implications of isolate heterogeneity.

Facilitated subcutaneous immunoglobulin (fSCIg) therapy--practical considerations

There is an increasing range of therapeutic options for primary antibody-deficient patients who require replacement immunoglobulin. These include intravenous immunoglobulin (IVIg), subcutaneous immunoglobulin (SCIg), rapid push SCIg and most recently recombinant human hyaluronidase-facilitated SCIg (fSCIg). Advantages of fSCIg include fewer needle punctures, longer infusion intervals and an improved adverse effect profile relative to IVIg. Limited real-life experience exists concerning the practical aspects of switching or starting patients on fSCIg. We describe the first 14 patients who have been treated with fSCIg at the Immunodeficiency Centre for Wales (ICW), representing more than 6 patient-years of experience. The regimen was well tolerated, with high levels of satisfaction and no increase in training requirement, including for a treatment-naive patient. Two patients discontinued fSCIg due to pain and swelling at the infusion site, and one paused therapy following post-infusion migraines. Ultrasound imaging of paired conventional and facilitated SCIg demonstrated clear differences in subcutaneous space distribution associated with a 10-fold increase in rate and volume delivery with fSCIg. Patient profiles for those choosing fSCIg fell into two main categories: those experiencing clinical problems with their current treatment and those seeking greater convenience and flexibility. When introducing fSCIg, consideration of the type and programming of infusion pump, needle gauge and length, infusion site, up-dosing schedule, home training and patient information are important, as these may differ from conventional SCIg. This paper provides guidance on practical aspects of the administration, training and outcomes to help inform decision-making for this new treatment modality.

RING finger protein 31 promotes p53 degradation in breast cancer cells

The atypical E3 ubiquitin ligase RNF31 is highly expressed in human breast cancer, the most frequent neoplastic lethality among women. Here, RNF31 depletion in breast cancer cells in combination with global gene expression profiling revealed p53 (TP53) signaling as a potential RNF31 target. Interestingly, RNF31 decreased p53 stability, whereas depletion of RNF31 in breast cancer cells caused cell cycle arrest and cisplatin-induced apoptosis in a p53-dependent manner. Furthermore, RNF31 associated with the p53/MDM2 complex and facilitated p53 polyubiquitination and degradation by stabilizing MDM2, suggesting a molecular mechanism by which RNF31 regulates cell death. Analysis of publically available clinical data sets displayed a negative correlation between RNF31 and p53 target genes, including IGFBP3 and BTG1, consistent with RNF31 regulating p53 function in vivo as well. Together, our findings suggest RNF31 as a potential therapeutic target to restore p53 function in breast cancer.

Search for patterns by combining cosmic-ray energy and arrival directions at the Pierre Auger Observatory

Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with [Formula: see text] eV by analyzing cosmic rays with energies above [Formula: see text] eV arriving within an angular separation of approximately 15[Formula: see text]. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.

In vivo detection of clinically non-apparent ocular surface inflammation in patients with meibomian gland dysfunction-associated refractory dry eye symptoms: a pilot study

PURPOSE

The utility of in vivo confocal microscopy (IVCM) in the investigation of palpebral conjunctival and corneal inflammation in patients with meibomian gland dysfunction (MGD)-associated refractory dry eye symptoms following gland expression, despite objective clinical improvement.

METHODS

A retrospective, observational pilot study was conducted evaluating five patients with MGD-associated refractory dry eye symptoms and three control groups: symptomatic untreated MGD patients (n=3), treatment-responsive MGD patients with improved symptoms (n=3) and asymptomatic healthy normals (n=11). Ocular surface disease index (OSDI) scores, tear break-up time (TBUT), the number of meibomian glands yielding liquid secretion (MGYLS), palpebral conjunctival epithelial and substantia propria immune cell (EIC, SIC), and corneal dendritic cell (DC) densities were measured.

RESULTS

Despite clinical improvement (TBUT: 6.4±1.2 s to 10.1±2.1 s, P=0.03; MGYLS: 3.5±0.8 glands to 7.0±1.1 glands, P=0.13) and a normal clinical examination post treatment, MGD patients remained symptomatic. IVCM revealed increased immune cells in the palpebral conjunctiva (refractory MGD EIC=592.6±110.1 cells/mm2 untreated MGD EIC=522.6±104.7 cells/mm2, P=0.69; responsive MGD EIC=194.9±119.4 cells/mm2, P<0.01; normals EIC=123.7±19.2 cells/mm2, P< 0.001), but not the cornea (refractory MGD DC=60.9±28.3 cells/mm2; normals DC=25.9±6.3 cells/mm2; P=0.43). EIC did not correlate with TBUT (Rs=-0.26, P=0.33). OSDI scores correlated with both EIC (Rs=0.76, P<0.001) and TBUT (Rs=-0.69, P<0.01) but not SIC. Intraglandular immune cells were also seen.

CONCLUSION

MGD-associated refractory symptoms and the symptom-sign disparity may be explained by clinically non-apparent, active inflammation of the palpebral conjunctiva as detected by IVCM. These patients may benefit from anti-inflammatory therapy.