Senescence Induced by BMI1 Inhibition Is a Therapeutic Vulnerability in H3K27M-Mutant DIPG

Diffuse intrinsic pontine glioma (DIPG) is an incurable brain tumor of childhood characterized by histone mutations at lysine 27, which results in epigenomic dysregulation. There has been a failure to develop effective treatment for this tumor. Using a combined RNAi and chemical screen targeting epigenomic regulators, we identify the polycomb repressive complex 1 (PRC1) component BMI1 as a critical factor for DIPG tumor maintenance in vivo. BMI1 chromatin occupancy is enriched at genes associated with differentiation and tumor suppressors in DIPG cells. Inhibition of BMI1 decreases cell self-renewal and attenuates tumor growth due to induction of senescence. Prolonged BMI1 inhibition induces a senescence-associated secretory phenotype, which promotes tumor recurrence. Clearance of senescent cells using BH3 protein mimetics co-operates with BMI1 inhibition to enhance tumor cell killing in vivo.

A Randomised Controlled Trial of Local Infiltration Analgesia Versus Femoral Nerve Block for Postoperative Analgesia Following Total Knee Arthroplasty

Background

Total knee replacement is often associated with significant postoperative pain. Although the use of a femoral nerve block is well-established, local infiltration analgesia has gained popularity in recent years. We compared single-shot local infiltration analgesia with a single-shot femoral nerve block for patients undergoing primary total knee arthroplasty.

Methods

A total of 194 patients were randomised to receive either local infiltration analgesia (150 ml bupivacaine 0.067% with adrenaline) or a femoral nerve block (20 ml 0.375% levobupivacaine). Both groups received spinal anaesthesia. The primary outcome measure was the total morphine consumption. Secondary outcome measures included: post-operative pain scores, rehabilitation goals, readiness for discharge, and physical, mental, and functional outcomes, including the Oxford Knee Score (OKS).

Results

A total of 69 patients in the local infiltration analgesia group and 79 patients in the femoral nerve block group were analysed. Median total morphine consumption was significantly greater in the local infiltration analgesia group as compared to the femoral nerve block group (54.67 mg vs 45 mg, respectively, p=0.0388). The post-operative OKS at six weeks was slightly more improved for the femoral nerve block group than for local infiltration analgesia (12.5 vs 9 point median improvements for the femoral nerve block and local infiltration analgesia groups, respectively, p=0.0261). There were no statistically significant differences in other secondary outcome measures.

Conclusion

A single-shot femoral nerve block significantly reduces the opioid requirement for primary total knee arthroplasty but is otherwise comparable to single-shot local infiltration analgesia. 

The effects of ephrinB2 signaling on proliferation and invasion in glioblastoma multiforme

The aggressive nature of glioblastoma multiforme (GBM) may be attributed to the dysregulation of pathways driving both proliferation and invasion. EphrinB2, a membrane-bound ligand for some of the Eph receptors, has emerged as a critical target regulating these pathways. In this study, we investigated the role of ephrinB2 in regulating proliferation and invasion in GBM using intracranial and subcutaneous xenograft models. The Cancer Genome Atlas analysis suggested high transcript and low methylation levels of ephrinB2 as poor prognostic indicators in GBM, consistent with its role as an oncogene. EphrinB2 knockdown, however, increased tumor growth, an effect that was reversed by ephrinB2 Fc protein. This was associated with EphB4 receptor activation, consistent with the data showing a significant decrease in tumor growth with ephrinB2 overexpression. Mechanistic analyses showed that ephrinB2 knockdown has anti-invasive but pro-proliferative effects in GBM. EphB4 stimulation following ephrinB2 Fc treatment in ephrinB2 knockdown tumors was shown to impart strong anti-proliferative and anti-invasive effects, which correlated with decrease in PCNA, p-ERK, vimentin, Snail, Fak, and increase in the E-cadherin levels. Overall, our study suggests that ephrinB2 cannot be used as a sole therapeutic target. Concomitant inhibition of ephrinB2 signaling with EphB4 activation is required to achieve maximal therapeutic benefit in GBM.

SAT0399 RISK OF OSTEOARTHRITIS IN AN INCIDENT COHORT OF PEOPLE WITH PSORIATIC ARTHRITIS: A POPULATION-BASED COHORT STUDY

Background:

Psoriatic arthritis (PsA) is a chronic inflammatory arthritis that causes pain, stiffness and swelling around the joints. PsA is reported to affect between 10 and 40% of individuals with psoriasis1and in the majority of patients presents after, or synchronously with, psoriasis onset.2Osteoarthritis (OA) is a common form of non-inflammatory arthritis related to joint degeneration and typically commences late in the fifth decade. PsA and OA have long been considered two distinct arthropathies, however they do have some overlapping features and symptoms and in certain circumstances it can be difficult to differentiate between them, particularly in the small joints of the hands or spine.3

Objectives:

To determine the risk of a diagnosis of osteoarthritis in psoriatic arthritis patients compared to patients with psoriasis and a general population cohort.

Methods:

Incident PsA patients aged 18-89 years at diagnosis were identified from the UK Clinical Practice Research Datalink between 1998 and 2014. All PsA patients were matched to a cohort of patients with psoriasis and a general population cohort (with no psoriasis or PsA) at a 1:4 ratio based on index date, year of birth, sex and general practice. The baseline prevalence of OA of any site was calculated as a percentage for each study cohort and then those prevalent cases were excluded from the numerators and denominators of the incident calculations. The incidence of OA was calculated and relative risks (RRadj), adjusting for body mass index (BMI), were calculated using conditional Poisson regression.

Results:

In total, 6,783 incident PsA patients were identified. The baseline prevalence of OA ranged from 22.1% (CI9521.1-23.1) in the PsA cohort to 12.6% (CI9512.2-13.0) and 11.0% (CI9510.6-11.3) in the psoriasis and general population cohorts respectively. The incidence of OA was significantly higher in the PsA cohort compared to the psoriasis and general population cohorts after adjusting for BMI (RRadj1.68 CI951.46-1.93 and RRadj1.86 CI951.62-2.14 respectively) (Tables 1 and 2).

Conclusion:

An increased risk of OA was observed in patients with PsA compared to patients with psoriasis alone and those in the general population. Further work is needed to determine whether this reflects a true increase in OA risk or misdiagnosed PsA and the extent to which it can be explained by differences in the opportunity for OA diagnosis between cohorts.

Table 1.

Incidence of osteoarthritis in the PsA, psoriasis and general population cohorts

CasesMedian age (years) at diagnosis (IQR)Person yearsIncidence rate per10,000 person yearsCI95Any OAϮGeneral population137459 (51 - 66)125,798109.2(103.5 - 115.0)Psoriasis143259 (53 - 67)122,279117.1(111.0 - 123.2)PsA46459 (51 - 66)28,574162.4(147.6 - 177.2)

Ϯincluding spondylosis

References:

[1]Ogdie A, Weiss P. Rheum Dis Clin North Am. 2015;41(4):545-568.

[2]Tillett Wet al.Rheumatol. 2017;56(12):2109-2113.

[3]McGonagle Det al. Rheumatology. 2015;54(1):29-38.

Table 2.

Risk of osteoarthritis in patients with PsA compared with patients in the general population and patients with psoriasis

PsA compared with a general population cohortPsA compared with a psoriasis cohortUnadjustedAdjusted†UnadjustedAdjusted†RRCI95PRRCI95PRRCI95PRRCI95POA1.871.67-2.10<0.00011.861.62-2.14<0.00011.681.50-1.88<0.00011.681.46-1.93<0.0001

†adjusted for BMI taken as the closest entry within 3 years of the index date

Acknowledgments:

This report is independent research funded by the National Institute for Health Research, Programme Grants for Applied Research [Early detection to improve outcome in patients with undiagnosed PsA (‘PROMPT’), RP-PG-1212-20007]. The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care.

Disclosure of Interests:

None declared

0167 The Effect of Nocturnal Dinner Type “Light” Versus “Heavy” on Sleep, Attention and Microbial Composition

Introduction

Nutrition and sleep are two essential functions for the physiological existence of the organism. Furthermore, both have an acquired cultural, educational and social behavioral component. This study examined the effect of nocturnal dinner type (“light” vs. “heavy”) on the quality and quantity of sleep, attention abilities, fatigue, and mood in the following morning. In addition, the microbial composition was examined.

Methods

Twenty healthy subjects (10 men and 10 women), aged 25–33, were invited to two non-consecutive nights at the Sleep Institute for polysomnography test and filling out questionnaires: KSS; ESS; and Brief Symptom Inventory (BSI), attention abilities assessed with CPT-III. In one evening, the subjects consumed two hours before bedtime a “light” dinner based on vegetable ingredients (vegetables and vegetable proteins) with 342 calories that contained lentils, feta cheese, beet, and other vegetables. On the other evening, the subjects consumed two hours before bedtime a “heavy” dinner based on carbohydrates, fats, and animal protein with 501 calories that contained hamburger and French fries. In addition, subjects were required to give a microbial test before and after meals.

Results

There was no significant difference in the various sleep parameters between the two nights after each meal type: efficacy (t=-1.51,p=0.15); sleep latency stage 1 (t=1.81,p=0.08); sleep latency stage 2 (t=1.00,p=0.33); REM latency (t=0.57,p=0.57); total sleep time (t=-1.57,p=0.13); number of awakenings (t=0.30, p=0.76). No significant differences were found for: fatigue (KSS) (t=-0.30,p =0.77); sleepiness (ESS) (t=0.76,p =0.45); mood (BSI) (t=0.87,p =0.39); and attention deficit (CPT-III) (t=-0.68,p =0.50). The type of night meal did not show a significant effect on the microbial composition (H=0.059,p= 0.81).

Conclusion

The findings of this study show that, contrary to popular belief, “heavy” dinner did not affect the quality of sleep and functions measured in the study compared to a “light” dinner. In the current research, the population that was examined included only young and healthy subjects, therefore, the results may differ if the research in this field will extend and include other populations such as adults and subjects with different disorders. Future studies are needed to examine the relationships between sleep and nutrtion.

Support

No support

0029 Light Emitted from Media Devices at Night is Associated with Decline in Sperm Quality

Introduction

The last several decades have been characterized by the widespread usage of digital devices, especially smartphones. At the same time, there have been reports of male fertility decline. The aim of this study was to assess the relationship between evening exposure to the light-emitting screens of digital media devices and sperm quality.

Methods

Semen samples were obtained from 116 men adults aged between 21 and 59 (35.2 ±7.2) undergoing fertility evaluation for the following sperm variables: volume (mL), pH, sperm concentration (n/mL), motility percentage (progressive% + non-progressive motility%) and total sperm count. Exposure to the screens of electronic devices and sleep habits were obtained by means of a questionnaire.

Results

Smartphone and tablet usage in the evening and after bedtime was negatively correlated (p&lt;0.05) with sperm motility, sperm progressive motility, and sperm concentration, and positively correlated with the percentage of immotile sperm. In addition, sleep duration was positively correlated with sperm total and progressive motility and negatively correlated with semen pH (p&lt;0.05). A significant negative correlation was observed between subjective sleepiness and total and progressive motility as well as total motile sperm number (p&lt;0.05).

Conclusion

The results of this study revealed a link between evening and post-bedtime exposure to light-emitting digital media screens and sperm quality. To the best of our knowledge, this is the first study to report these types of correlations between sperm quality and exposure time to SWL emitted from digital media, especially smartphones and tablets, in the evening and after bedtime.

Support

No Support

Molecular predictors of response to selinexor in recurrent glioblastoma (GBM)

2565

Background: The nuclear export protein exportin 1 (XPO1) is overexpressed in many cancers, including GBM. Selinexor is an inhibitor of XPO1 that crosses the blood-brain-barrier and targets cancer cells by sequestering tumor suppressor proteins and oncoprotein mRNAs in the cell nucleus, inducing cancer cell apoptosis. Selinexor is FDA approved for treatment of patients (pts) with refractory multiple myeloma and is under evaluation for GBM. Methods: We previously reported encouraging results from a phase II clinical trial of selinexor for molecularly unselected pts with recurrent GBM (ASCO 2019). On available pre-treatment archival tumor tissue from 57 cases, we performed DNA exome and RNA transcriptome sequencing to use both gene mutations and expressions for exploring molecular correlates of response in selinexor treated pts, in a hypothesis generating, post-hoc, exploratory analysis. Pts with inadequate drug exposure were excluded ( < 21 days or < 3 doses). We compared OS and PFS between mutated and wild-type patients for genes mutated in at least 5 cases. RNAseq data were used to infer differential protein activities between patients with selinexor sensitive disease (defined as best response of partial or complete response, n = 7) vs. resistant disease (defined as progressive disease as best response, n = 23). Results: Two mutated genes were associated with longer survival in selinexor treated pts: DOCK8 (n = 7; progression free survival [PFS], P = 0.013, hazard ratio [HR] = 3.75 [1.32-10.62]; overall survival, P = 0.009, HR = 15.39 [2.00-118.34]) and PDX1 (n = 5, PFS, P = 0.014, HR = 4.468 [1.361-14.670]). Other commonly mutated genes in glioma, including IDH1 (n = 9) were observed but not associated with survival. Protein activities inferred from RNA sequencing data were also correlated with response to selinexor. In a machine learning model, ZC3H12A (also called MCPIP-1), a negative regulator of inflammation; RAB43, a member of the RAS family that binds GTP and regulates vesicle trafficking, and SOCS3, a suppressor of cytokine signaling that can antagonize JAK/STAT signaling and repress innate immunity, predicted clinical benefit from selinexor (area under the ROC curve from leave one out cross validation = 0.89, permutation test P < 0.04). Conclusions: DOCK8 and PDX1 mutations were favorable prognostic factors in selinexor treated pts. Activity of three proteins (ZC3H12A, RAB43, and SOCS3) predicted clinical benefit from selinexor. Further studies with more pts are required to validate our findings. ClinicalTrials.gov: NCT01986348

Patient deprivation and perceived scan burden negatively impact the quality of whole-body MRI

AIM

To evaluate the association between the image quality of cancer staging whole-body magnetic resonance imaging (WB-MRI) and patient demographics, distress, and perceived scan burden.

MATERIALS AND METHODS

A sample of patients recruited prospectively to multicentre trials comparing WB-MRI with standard scans for staging lung and colorectal cancer were invited to complete two questionnaires. The baseline questionnaire, administered at recruitment, collated data on demographics, distress and co-morbidity. The follow-up questionnaire, completed after staging investigations, measured perceived WB-MRI scan burden (scored 1 low to 7 high). WB-MRI anatomical coverage, and technical quality was graded by a radiographic technician and grading combined to categorise the scan as "optimal", "sub-optimal" or "degraded". A radiologist categorised 30 scans to test interobserver agreement. Data were analysed using the chi-square, Fisher's exact, t-tests, and multinomial regression.

RESULTS

One hundred and fourteen patients were included in the study (53 lung, 61 colorectal; average age 65.3 years, SD=11.8; 66 men [57.9%]). Overall, 45.6% (n=52), scans were classified as "optimal" quality, 39.5% (n=45) "sub-optimal", and 14.9% (n=17) as "degraded". In adjusted analyses, greater deprivation level and higher patient-reported scan burden were both associated with a higher likelihood of having a sub-optimal versus an optimal scan (odds ratio [OR]: 4.465, 95% confidence interval [CI]: 1.454 to 13.709, p=0.009; OR: 1.987, CI: 1.153 to 3.425, p=0.013, respectively). None of the variables predicted the likelihood of having a degraded scan.

CONCLUSIONS

Deprivation and patients' perceived experience of the WB-MRI are related to image quality. Tailored protocols and individualised patient management before and during WB-MRI may improve image quality.

Targeting MYC-driven replication stress in medulloblastoma with AZD1775 and gemcitabine

PURPOSE

MYC-driven medulloblastomas are highly aggressive childhood tumors with dismal outcomes and a lack of new treatment paradigms. We identified that targeting replication stress through WEE1 inhibition to suppress the S-phase replication checkpoint, combined with the attenuation of nucleotide synthesis with gemcitabine, is an effective strategy to induce apoptosis in MYC-driven medulloblastoma that could be rapidly translated into early phase clinical trials in children. Attenuation of replication stress is a key component of MYC-driven oncogenesis. Previous studies revealed a vulnerability in MYC medulloblastoma through WEE1 inhibition. Here, we focused on elucidating combinations of agents to synergize with WEE1 inhibition and drive replication stress toward cell death.

METHODS

We first analyzed WEE1 expression in patient tissues by immunohistochemistry. Next, we used high-throughput drug screens to identify agents that would synergize with WEE1 inhibition. Synergy was confirmed by in vitro live cell imaging, ex vivo slice culture models, and in vivo studies using orthotopic and flank xenograft models.

RESULTS

WEE1 expression was significantly higher in Group 3 and 4 medulloblastoma patients. The WEE1 inhibitor AZD1775 synergized with inhibitors of nucleotide synthesis, including gemcitabine. AZD1775 with gemcitabine suppressed proliferation and induced apoptosis. Ex vivo modeling demonstrated efficacy in Group 3 medulloblastoma patients, and in vivo modeling confirmed that combining AZD1775 and gemcitabine effectively suppressed tumor growth.

CONCLUSION

Our results identified a potent new synergistic treatment combination for MYC-driven medulloblastoma that warrants exploration in early phase clinical trials.

PL3.5 Efficacy and safety of selinexor in recurrent glioblastoma

BACKGROUND

New treatment modalities are needed for recurrent glioblastoma (rGBM). Selinexor is a novel, oral selective inhibitor of nuclear export which forces nuclear retention of tumor suppressor proteins including p53 and p27, leading to apoptosis. We previously reported interim results showing tolerability, preliminary efficacy, and blood-brain barrier penetration in a surgical cohort (N=8). We now report updated results following completion of accrual to non-surgical cohorts (N=68).

MATERIALS AND METHODS

This is an open-label, multicenter, phase 2 study of selinexor monotherapy. Patients (pts) not undergoing surgery for measurable rGBM per response assessment neuro-oncology criteria (RANO) were enrolled in one of 3 arms encompassing different dosing schedules of selinexor (50 mg/m2 [~ 85 mg] BIW, 60 mg BIW, and 80 mg QW). Treatment was continuous, although cycles were defined as 28 days and response was assessed every other cycle by MRI. Prior treatment with radiotherapy and temozolomide was required and prior bevacizumab was exclusionary. The primary endpoint was 6-month progression free survival (6mPFS) rate, calculated by the Kaplan-Meier method.

RESULTS

76 pts were enrolled; 24, 14 and 30 pts on doses of ~85 mg BIW, 60 mg BIW, and 80 mg QW, respectively. Median age was 56 years (range 21–78). Median number of prior treatments was 2 (range 1–7)

At the end of the 6 cycles, 30.2% pts on 80 mg QW were free from progression. The 6mPFS rate on 80 mg QW was 18.9%. Best RANO-defined responses (assessed locally) among 26 evaluable pts on 80 mg QW included 1 complete response, 2 partial responses, 7 stable disease, and 16 with progressive disease. Complete and partial responses were durable: the complete and a partial responder remain on selinexor for 393 and 1093 days respectively, as of the cut-off date. Median duration of response was 10.8 months. The most common related adverse events (all grades) in pts on ~85 mg BIW/60 mg BIW/80 mg QW were nausea (42%/64%/63%), leukopenia (38%/7%/43%), fatigue (71%/71%/47%), neutropenia (29%/14%/33%), decreased appetite (46%/71%/27%), and thrombocytopenia (67%/29%/23%).

CONCLUSION

Selinexor demonstrated efficacy, with durable responses and disease stabilization in rGBM. Based on the favorable efficacy and safety profile, selinexor at a dose of 80 mg QW is recommended for further development in rGBM.

Pharmacological treatment for Type 2 diabetes integrating findings from cardiovascular outcome trials: an expert consensus in the UK

In people with Type 2 diabetes, cardiovascular disease is a leading cause of morbidity and mortality. Thus, as well as controlling glucose, reducing the risk of cardiovascular events is a key goal. The results of cardiovascular outcome trials have led to updates for many national and international guidelines. England, Wales and Northern Ireland remain exceptions, with the most recent update to the National Institute for Health and Care Excellence (NICE) guidelines published in 2015. We reviewed current national and international guidelines and recommendations on the management of people with Type 2 diabetes. This article shares our consensus on clinical recommendations for the use of sodium-glucose co-transporter 2 inhibitors (SGLT-2is) and glucagon-like peptide 1 receptor agonists (GLP-1RAs) in people with Type 2 diabetes and established or at very high risk of cardiovascular disease in the UK. We also consider cost-effectiveness for these therapies. We recommend considering each person's cardiovascular risk and using diabetes therapies with proven cardiovascular benefits when appropriate to improve long-term outcomes and cost-effectiveness.

Assessment of enrollment characteristics for Children’s Oncology Group (COG) upfront therapeutic clinical trials 2004-2015

6564

Background: Improvements in pediatric cancer survival are attributed to cooperative clinical trials. Under representation of specific demographic groups has been described in adult and pediatric cancer and poses a threat to the generalizability of trial results. A comprehensive evaluation of data provided by the Children’s Oncology Group (COG) of upfront trial enrollment for US patients 0 to 29 years old between 2004 and 2015 was performed to assess for disparities in participation. Methods: Estimates of cancer cases were calculated using the Surveillance, Epidemiology, and End Results registry and the US Census and compared to observed COG cases. Percent enrollment and Standardized Ratios of enrollment were calculated across various demographic, disease, and socioeconomic groups. The COG website was utilized to quantify available upfront trials during the study period and assess age eligibility criteria. Results: 21.3% of estimated US cancer patients age 0 to 19 years enrolled on COG trials. Younger patients were consistently more represented across disease types and race/ethnicities. Patients with hematologic malignancies were more represented compared to solid and central nervous system (CNS) tumors. Conclusions: COG clinical trial enrollment rates are declining, which may be due to challenges in pediatric drug development, difficulty designing feasible trials for highly curable diseases, and issues in ensuring trial availability for the heterogeneous group of solid and CNS tumors. Though racial/ethnic groups and county-level socioeconomic factors were proportionally represented, under representation of the adolescent/young adult (AYA) population and younger patients with solid and CNS tumors remain significant concerns. Targeted enrollment efforts should focus on the identified subgroups and further research should evaluate AYA enrollment across all available trials to provide continued treatment advances for all patients.