Enhancing the health knowledge and health literacy of recently resettled refugees through classroom-based instructional methods

Health education can elevate health literacy, which is associated with health knowledge, health-seeking behaviors and overall improved health outcomes. Refugees are particularly vulnerable to the effects of low health knowledge and literacy, which can exacerbate already poor health stemming from their displacement experience. Traditional learning methods including classroom-based instruction are typically how health-related information is presented to refugees. Through a series of interactive classes focused on specific health topics relevant to the resettled refugee population, this study evaluated the effectiveness of a classroom-based health education model in enhancing the health knowledge of recently resettled refugees. We used the Wilcoxon signed-rank test to evaluate differences in pre- and post-class knowledge through test performance. We found a significant improvement in health knowledge in two refugee groups: females and those who were employed. Culturally and socially sensitive considerations including language inclusiveness, class timing, transportation and childcare provisions are important when creating an educational program for individuals with refugee backgrounds. Developing focused approaches to instruction that enhance health knowledge could lead to better health literacy and ultimately improve health-related behaviors and outcomes in the refugee population.

URINE TOXICOLOGY PROFILES OF EMERGENCY DEPARTMENT PATIENTS WITH UNTREATED OPIOID USE DISORDER: A MULTI-SITE VIEW

BACKGROUND

Opioid overdose deaths in 2021 were the highest ever, driven by fentanyl and polysubstance use.

OBJECTIVE

The aim of the study was to characterize drug use, assessed by urine drug screens (UDSs), in patients with untreated opioid use disorder (OUD) presenting to 28 emergency departments (EDs) nationally and by region.

METHODS

We analyzed UDSs from patients enrolled in the CTN-0099 ED-INNOVATION (Emergency Department-Initiated Buprenorphine Validation) trial between July 12, 2020 and March 9, 2022. Participants were adult ED patients with OUD not engaged in addiction treatment with a UDS positive for an opioid, but negative for methadone. Sites were divided into "East" and "West" regions.

RESULTS

A UDS was available for all 925 enrolled participants, 543 from East and 382 from West. Fentanyl was in 702 specimens (76%) (n = 485 [89%] East vs. n = 217 [57%] West; p < 0.01) and was the only opioid in 269 (29%). After fentanyl, the most common opioids were morphine (presumably heroin; n = 411 [44%]; n = 192 [35%] East vs. n = 219 [57%] West; p < 0.01) and buprenorphine (n = 329 [36%]; n = 186 [35%] East vs. n = 143 [37%] West; p = 0.32). The most common drugs found with opioids were stimulants (n = 545 [59%]), tetrahydrocannabinol (n = 417 [45%]), and benzodiazepines (n = 151 [16%]). Amphetamine-type stimulants were more common in West (n = 209 [55%] vs. East (n = 125 [23%]). Cocaine was more common in East (n = 223 [41%]) vs. West (n = 82 [21%]). The presence of multiple drugs was common (n = 759 [82%]).

CONCLUSIONS

Most participants had UDS specimens containing multiple substances; a high proportion had fentanyl, stimulants, and buprenorphine. Regional differences were noted. Given the increased risk of death with fentanyl and polysubstance use, ED providers should be providing risk reduction counseling, treatment, and referral.

Efficacy of Osimertinib in Patients with Lung Cancer Positive for Uncommon EGFR Exon 19 Deletion Mutations

PURPOSE

The uncommon EGFR exon 19 deletion (ex19del), L747_A750>P, demonstrates reduced sensitivity to osimertinib compared with the common ex19del, E746_A750del in preclinical models. The clinical efficacy of osimertinib in patients with non-small cell lung cancer harboring L747_A750>P and other uncommon ex19dels is not known.

EXPERIMENTAL DESIGN

The AACR GENIE database was interrogated to characterize the frequency of individual ex19dels relative to other variants, and a multicenter retrospective cohort was used to compare clinical outcomes for patients with tumors harboring E746_A750del, L747_A750>P, and other uncommon ex19dels who received osimertinib in the first line (1L) or in second or later lines of therapy and were T790M+ (≥2L).

RESULTS

ex19dels comprised 45% of EGFR mutations, with 72 distinct variants ranging in frequency from 28.1% (E746_A750del) to 0.03%, with L747_A750>P representing 1.8% of the EGFR mutant cohort. In our multi-institutional cohort (N = 200), E746_A750del was associated with significantly prolonged progression-free survival (PFS) with 1L osimertinib versus L747_A750>P [median 21.3 months (95% confidence interval, 17.0-31.7) vs. 11.7 months (10.8-29.4); adjusted HR 0.52 (0.28-0.98); P = 0.043]. Osimertinib efficacy in patients with other uncommon ex19dels varied on the basis of the specific mutation present.

CONCLUSIONS

The ex19del L747_A750>P is associated with inferior PFS compared with the common E746_A750del mutation in patients treated with 1L osimertinib. Understanding differences in osimertinib efficacy among EGFR ex19del subtypes could alter management of these patients in the future.

Risk Factors for Common Kidney Stones Are Correlated with Kidney Function Independent of Stone Composition

INTRODUCTION

Kidney stone type varies with age, sex, season, and medical conditions. Lower estimate glomerular filtration rate (eGFR) leads to changes in urine chemistry, and risk factors for kidney stones are thought to vary by stone type. We explore the association between eGFR, urine risk factors, and common stone compositions.

METHODS

This was a retrospective cohort study of 811 kidney stone patients seen at Yale Medicine between 1994 and 2021 with serum chemistries and 24-h urine chemistries matched within 1 year of baseline stone analysis. Patients' eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 equation. Demographics and medical history were compared by χ2 tests. 24-h urine chemistries and stone analyses were analyzed by one-way ANOVA. Linear regressions were performed to control for demographics, comorbidities, and stone composition.

RESULTS

With lower eGFR, the proportion of calcium stones declined while uric acid (UA) stones increased. On univariable analysis, lower eGFR was associated with lower urine pH, calcium, citrate, UA, magnesium, phosphorus, and ammonium. On multivariable analysis, controlling for age, sex, ethnicity, body mass index, comorbidities, and stone type, these factors remained significant. Stone formers with lower eGFR had elevated supersaturation for UA, but reduced supersaturations for calcium-containing stones. Though urine oxalate was significant on univariable analysis, it was not on multivariable analysis.

CONCLUSION

Changes in urine parameters are strongly correlated with eGFR regardless of stone type. Renal function may play a key role in modulating kidney stone risk factors. Strategies to mitigate stone risk may need to vary with kidney function, especially when patient urine or stone composition data are unavailable.

Nocturnal Dipping and Kidney Function Decline: Findings From the CKD in Children Study

Introduction

Normally, blood pressure (BP) declines by at least 10% from daytime to nighttime. In adults, blunted nocturnal dipping has been associated with more rapid decline in kidney function. Nondipping is prevalent in children with chronic kidney disease (CKD). We sought to determine whether nondipping is associated with proteinuria and progression to kidney failure in children with CKD.

Methods

In the prospective CKD in children (CKiD) cohort, Cox proportional hazards models were used to evaluate the relationship between baseline nondipping and progression to kidney failure. Linear mixed effects models were used to evaluate the relationship between nondipping and changes in iohexol glomerular filtration rate (GFR) and urine protein-to-creatinine ratio (log-UPCR, mg/mg) over time.

Results

Among 620 participants, mean age was 11 (± 4) years, mean iohexol GFR was 52 (± 22) ml/min per 1.73 m2, and 40% were nondippers at baseline. There were 169 kidney failure events during 2.9 years (median) of follow-up. Dipping status was not significantly associated with kidney failure overall (hazard ratio [HR] 1.08; 95% confidence interval [CI] 0.77, 1.51) or in those with (HR 1.21; 95% CI 0.53, 2.77) or without (HR 1.05; 95% CI 0.71, 1.55) glomerular disease. Dipping status did not modify the relationship between time and change in iohexol GFR or log (UPCR) from baseline (interaction P values = 0.20 and 0.054, respectively).

Conclusion

Nondipping is not associated with end-stage kidney disease, GFR decline, or change in proteinuria within the CKiD cohort.

Efficacy of osimertinib in patients with EGFR mutant lung cancer harboring the uncommon exon 19 deletion, L747_A750>P

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Background: EGFR exon 19 deletions (del19) are largely considered to have uniform sensitivity to EGFR tyrosine kinase inhibitors (TKIs). Approximately 70% of del19 tumors harbor the most common deletion, E756_A750del; however, many “uncommon” variants comprise the remainder of this group. In preclinical studies, the uncommon del19, L747_A750 > P, demonstrates diminished sensitivity to the third generation TKI, osimertinib [. Identifying differences in clinical outcomes with osimertinib treatment could have therapeutic implications for patients (pts) with EGFR del19 non-small cell lung cancer (NSCLC). Methods: We conducted a multi-center retrospective cohort study of pts with metastatic EGFR del19 NSCLC treated with osimertinib. We compared progression free survival (PFS, time from TKI initiation to clinically significant growth of existing lesions or new lesions on imaging or death) and overall survival (OS) of pts with tumors harboring E746_A750del and L747_A750 > P who received osimertinib in the first line (1L) or in second or later lines of therapy and were T790M+ (≥2L). The Kaplan Meier method and Cox model were used to estimate PFS and OS, and multivariable logistic regression was used to estimate the odds of achieving PFS > 12 months. Multivariable analyses adjusted for baseline covariates- age, sex, race, and smoking. Results: From March 2013 to December 2021, 86 pts with EGFR E746_A750del and 36 with L747_A750 > P were treated with osimertinib. For 1L osimertinib, E746_A750del was associated with significantly prolonged PFS vs. L747_A750 > P (median 21.3 months (95% CI 17.0-31.7) vs. 11.7 months (10.8-29.4)) in the adjusted analysis (hazard ratio [HR] 0.52 [95% CI, 0.28-0.98, p = 0.043]). Pts with the common del19 mutation were more likely to achieve PFS > 12 months with 1L osimertinib than those with the L747_A750 > P mutation (Odds Ratio 4.14 (1.41-12.15), p 0.0097). OS exhibited a similar trend with a median OS that that was not reached (NR) at 40 months of follow-up among those with E746_A750del vs 26 months for L747_A750 > P (adjusted HR 0.52 [95% CI, 0.23-1.19], p = 0.120). For pts treated with ≥2L osimertinib, there was also a trend towards favorable PFS and OS for pts with tumors harboring E746_A750del. Conclusions: The del19 mutation L747_A750 > P is associated with inferior PFS compared to the common E746_A750del mutation in pts treated with 1L osimertinib. Understanding differences in osimertinib efficacy among EGFR del19 subtypes could alter management of these pts in the future.[Table: see text]

[89Zr]ZrDFO-CR011 positron emission tomography correlates with response to glycoprotein non-metastatic melanoma B-targeted therapy in triple negative breast cancer

There is a need for prognostic markers to select patients most likely to benefit from antibody drug conjugate (ADC) therapy. We quantified the relationship between pre-treatment positron emission tomography (PET) imaging of glycoprotein non-metastatic melanoma B (gpNMB) with 89Zr-labeled anti-gpNMB antibody ([89Zr]ZrDFO-CR011) and response to ADC therapy (CDX-011) in triple negative breast cancer (TNBC). First, we compared different PET imaging metrics and found that standardized uptake values (SUV) and tumor-to-heart SUV ratios (SUVR) were sufficient to delineate differences in radiotracer uptake in the tumor of four different cell- and patient-derived tumor models and achieved high standardized effect sizes. These tumor models with varying levels of gpNMB expression were imaged with [89Zr]ZrDFO-CR011 followed by treatment with a single bolus injection of CDX-011. The percent change in tumor volume relative to baseline (% CTV) was then correlated with SUVmean of [89Zr]ZrDFO-CR011 uptake in the tumor. All gpNMB-positive tumor models responded to CDX-011 over 6 weeks of treatment, except one patient-derived tumor re-grew after 4 weeks of treatment. As expected, the gpNMB-negative tumor increased in volume by 130 {plus minus} 59 % at endpoint. The magnitude of pre-treatment SUV had the strongest inverse correlation with the % CTV at 2 - 4 weeks after treatment with CDX-011 (Spearman ρ = -0.8). However, pre-treatment PET imaging with [89Zr]ZrDFO-CR011 did not inform on which tumor types will re-grow over time. Other methods will be needed to predict resistance to treatment.

Association of AKI-D with Urinary Findings and Baseline eGFR in Hospitalized COVID-19 Patients

Background

AKI is common in patients hospitalized with coronavirus disease 2019 (COVID-19). Risk factors for AKI requiring dialysis (AKI-D) are not fully understood. We aimed to identify risk factors associated with AKI-D and AKI not requiring dialysis (AKI-ND).

Methods

We reviewed electronic health records of 3186 patients aged ≥18 years old who were hospitalized with COVID-19 across six hospitals. Patient characteristics, urinalysis findings, and inflammatory markers were analyzed for association with in-hospital AKI status (AKI-D, AKI-ND, or no AKI), and we subsequently evaluated mortality.

Results

After adjustment for multiple covariates, higher baseline eGFR was associated with 30% lower odds of AKI-D and 11% lower odds of AKI-ND (for AKI-D, OR, 0.70; 95% CI, 0.64 to 0.77; for AKI-ND, OR, 0.89; 95% CI, 0.85 to 0.92). Patients with obesity and those who were Latino had increased odds of AKI-D, whereas patients with congestive heart failure or diabetes with complications had increased odds of AKI-ND. Females had lower odds of in-hospital AKI (for AKI-D, OR, 0.28; 95% CI, 0.17 to 0.46; for AKI-ND, OR, 0.83; 95% CI, 0.70 to 0.99). After adjustment for covariates and baseline eGFR, 1-4+ protein on initial urinalysis was associated with a nine-fold increase in odds of AKI-D (OR, 9.00; 95% CI, 2.16 to 37.38) and more than two-fold higher odds of AKI-ND (OR, 2.28; 95% CI, 1.66 to 3.13). Findings of 1-3+ blood and trace glucose on initial urinalysis were also associated with increased odds of both AKI-D and AKI-ND. AKI-D and AKI-ND were associated with in-hospital death (for AKI-D, OR, 2.64; 95% CI, 1.13 to 6.17; for AKI-ND, OR, 2.44; 95% CI, 1.77 to 3.35).

Conclusions

Active urine sediments, even after adjustment for baseline kidney function, and reduced baseline eGFR are significantly associated with increased odds of AKI-D and AKI-ND. In-hospital AKI was associated with in-hospital death. These findings may help prognosticate patients hospitalized with COVID-19.

LMD-03. Single cell analysis reveals how therapy remodels the tumor microenvironment in melanoma CNS metastases and uncovers a novel predictor of improved survival

We interrogated the microenvironment of 43 clinical samples from melanoma skin, brain (MBM) and leptomeningeal metastases (LMM) using single-cell RNA-seq analysis to determine how therapeutic intervention shaped the immune environment and affected patient survival. LMM is a poorly-characterized, devastating complication of late-stage disease, typically refractory to treatment and associated with dismal survival time. Analysis of serial specimens over the course of therapy demonstrated reductions in melanoma cells and macrophages, coupled with increased levels of T cells and dendritic cells in the CSF of a rare extraordinary responder, whereas typical poor survivors showed no improvement in T cell responses. In MBM patients, both targeted therapy and immunotherapy was associated with increased immune infiltrate. Treatment with targeted therapy was associated with an enrichment of CD8 T cells, while immunotherapy was associated with a more diverse lymphocyte landscape and higher numbers of antibody-producing cells. These findings were confirmed by multiplex-IF staining of patient specimens and using an immune-competent mouse model of MBM. Interestingly, a history of prior radiation therapy was associated with a diminished myeloid compartment. Although immune infiltrate was significantly lower in the brain compared to skin tumors, the phenotypic make-up of the lymphocyte compartment was quite similar, suggesting that the immune cells may have trafficked from the periphery to the brain post-therapy. Correlation analysis across the entire immune landscape identified the presence of a rare, novel population of dendritic cells (DC3s) to be correlated with increased overall survival, regardless of disease site/treatment. The presence of DC3s positively regulated the immune environment of both patient samples and preclinical melanoma models through modulation of activated T cells and MHC expression in the tumor. Overall, we present the first ever comprehensive single-cell atlas of the tumor microenvironment in melanoma CNS metastases in response to therapy.

OTME-17. Single cell characterization of the immune microenvironment of melanoma brain and leptomeningeal metastases

Melanoma brain metastases (MBM) and leptomeningeal metastases (LMM) are two manifestations of melanoma dissemination to the CNS with vastly different survival outcomes. Analysis of single cell RNA-Seq data from 43 clinical specimens has uncovered a distinct, immune-suppressed T cell landscape in the LMM microenvironment that is distinct to those of the brain and skin metastases. An LMM patient with an extraordinarily long survival and documented response to therapy demonstrated an immune repertoire that was distinct from those of typical poor survivors and more similar to CSF from non-LMM donors. Analysis of serial specimens over the course of therapy demonstrated reductions in melanoma cells and macrophages, coupled with increased levels of T cells and dendritic cells in the CSF of the extraordinary responder, whereas poor survivors showed no improvement in T cell responses. In MBM patients, targeted therapy and immunotherapy was associated with increased immune infiltrate, with similar T cell transcriptional diversity noted between skin metastases and MBM - suggestive of immune cell trafficking into the brain. Treatment with targeted therapy was associated with an enrichment of CD8 T cells. Immunotherapy was associated with a more diverse lymphocyte landscape and higher numbers of antibody-producing cells. These findings were confirmed by multiplexed staining of patient specimens and using an immune-competent mouse model of MBM. Correlation analysis across the entire immune landscape identified the presence of a rare, novel population of dendritic cells (DC3s) to be correlated with increased overall survival, regardless of disease site/treatment. The presence of DC3s positively regulated the immune environment of both patient samples and preclinical melanoma models through modulation of activated T cells and MHC expression in the tumor. Our study provides the first comprehensive atlas of two distinct sites of melanoma CNS metastases and identifies rare populations of cells that underlie the biology of this devastating disease.

Single-Cell Characterization of the Immune Microenvironment of Melanoma Brain and Leptomeningeal Metastases

PURPOSE

Melanoma brain metastases (MBM) and leptomeningeal melanoma metastases (LMM) are two different manifestations of melanoma CNS metastasis. Here, we used single-cell RNA sequencing (scRNA-seq) to define the immune landscape of MBM, LMM, and melanoma skin metastases.

EXPERIMENTAL DESIGN

scRNA-seq was undertaken on 43 patient specimens, including 8 skin metastases, 14 MBM, and 19 serial LMM specimens. Detailed cell type curation was performed, the immune landscapes were mapped, and key results were validated by IHC and flow cytometry. Association analyses were undertaken to identify immune cell subsets correlated with overall survival.

RESULTS

The LMM microenvironment was characterized by an immune-suppressed T-cell landscape distinct from that of brain and skin metastases. An LMM patient with long-term survival demonstrated an immune repertoire distinct from that of poor survivors and more similar to normal cerebrospinal fluid (CSF). Upon response to PD-1 therapy, this extreme responder showed increased levels of T cells and dendritic cells in their CSF, whereas poor survivors showed little improvement in their T-cell responses. In MBM patients, therapy led to increased immune infiltrate, with similar T-cell transcriptional diversity noted between skin metastases and MBM. A correlation analysis across the entire immune landscape identified the presence of a rare population of dendritic cells (DC3) that was associated with increased overall survival and positively regulated the immune environment through modulation of activated T cells and MHC expression.

CONCLUSIONS

Our study provides the first atlas of two distinct sites of melanoma CNS metastases and defines the immune cell landscape that underlies the biology of this devastating disease.

Abstract P847: Exploring the Perspective of Patient Recipients of a Provider and Systems-Level Intervention - A Mixed Methods Analysis From the Care Transitions and Hypertension Management (catch) Program for Ischemic Stroke Study

Introduction: The CAre Transitions and Hypertension management (CATcH) program was developed using Lean Six Sigma methodology and is a bundled, multi-faceted, provider- and healthcare systems-level pilot-intervention designed to enhance care coordination. Components of the intervention included: education delivered during the hospitalization, increased utilization of clinical pharmacy and home telehealth for blood pressure (BP) monitoring, and a patient care navigator.

Hypothesis: Recipients of CATcH will find the program valuable though engaging with additional care providers may be deemed onerous.

Methods: Twenty-eight semi-structured qualitative interviews were conducted between June 2018 and June 2019 among CATcH recipients. Interviews were audio-recorded, transcribed, and entered into an ATLAS.ti. project file. Thematic Content Analysis was used to analyze coded data, generate, and validate findings. Themes related to the overall impression of CATcH and its individual components were investigated across all patients and stratified by age, race, sex, and when they were discharged in relation to beginning of CATcH implementation.

Results: A total of 108 Veterans were the recipients of CATcH. All patients received education, patient care navigator services, and offered both clinical pharmacy and telehealth services, with 52/108 (48.1%) attending clinical pharmacy appointments and 37/108 (34.3%) utilizing telehealth services within 6-months post-discharge. Subjects interviewed were on average 68.6±8.2 years of age, predominantly male (26/28; 92.9%) and equally distributed among black and non-black races. Themes were largely positive with patients expressing they were unaware that they were the recipients of an enhanced care program, and that CATcH. Patients who received CATcH in the second half of the program reported better care collaboration and more useful educational materials that those enrolled earlier in the project.

Conclusions: Patients found the CATcH program and its component parts useful in the ongoing management of post-stroke BP control. Continuous self-evaluation and refinement of the program throughout the intervention period likely contributed to improvements in care collaboration and education.

Melanoma brain metastases: Biological basis and novel therapeutic strategies

The development of brain metastases is the deadliest complication of advanced melanoma and has long been associated with a dismal prognosis. The recent years have seen incredible progress in the development of therapies for melanoma brain metastases (MBM), with both targeted therapies (the BRAF-MEK inhibitor combination) and immune checkpoint inhibitors (the anti-CTLA-4, anti-PD-1 combination) showing impressive levels of activity. Despite this, durations of response for these therapies remain lower at intracranial sites of metastasis compared to extracranial metastases and it has been suggested that there are unique features of the brain microenvironment that contribute to therapeutic escape. In this review, we outline the latest research into the biology and pathophysiology of melanoma brain metastasis development and progression. We then discuss the current status of clinical trial that are open to patients with MBM and end by describing the ongoing challenges for the field.

Association of Demographic and Early-Life Socioeconomic Factors by Birth Cohort With Dementia Incidence Among US Adults Born Between 1893 and 1949

IMPORTANCE

Early-life factors may be important for later dementia risk. The association between a more advantaged early-life environment, as reflected through an individual's height and socioeconomic status indicators, and decreases in dementia incidence by birth cohort is unknown.

OBJECTIVES

To examine the association of birth cohort and early-life environment with dementia incidence among participants in the Adult Changes in Thought study from 1994 to 2015.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study included 4277 participants from the Adult Changes in Thought study, an ongoing longitudinal population-based study of incident dementia in a random sample of adults 65 years and older who were born between 1893 and 1949 and are members of Kaiser Permanente Washington in the Seattle region. Participants in the present analysis were followed up from 1994 to 2015. At enrollment, all participants were dementia-free and completed a baseline evaluation. Subsequent study visits were held every 2 years until a diagnosis of dementia, death, or withdrawal from the study. Participants were categorized by birth period (defined by historically meaningful events) into 5 cohorts: pre-World War I (1893-1913), World War I and Spanish influenza (1914-1920), pre-Great Depression (1921-1928), Great Depression (1929-1939), and World War II and postwar (1940-1949). Participants' height, educational level, childhood financial stability, and childhood household density were examined as indicators of early-life environment, and later-life vascular risk factors for dementia were assessed. Cox proportional hazards regression models, adjusted for competing survival risk, were used to analyze data. Data were analyzed from June 1, 2018, to April 29, 2020.

MAIN OUTCOMES AND MEASURES

Participants completed the Cognitive Abilities Screening Instrument every 2 years to assess global cognition. Those with scores indicative of cognitive impairment completed an evaluation for dementia, with dementia diagnoses determined during consensus conferences using criteria from the Diagnostic and Statistical Manual of Mental Disorders, 4th edition.

RESULTS

Among 4277 participants, the mean (SD) age was 74.5 (6.4) years, and 2519 participants (58.9%) were women. The median follow-up was 8 years (interquartile range, 4-12 years), with 730 participants developing dementia over 24 378 person-years. The age-specific dementia incidence was lower for those born in 1929 and later compared with those born earlier. Compared with participants born in the pre-Great Depression years (1921-1928), the age- and sex-adjusted hazard ratio was 0.67 (95% CI, 0.53-0.85) for those born in the Great Depression period (1929-1939) and 0.62 (95% CI, 0.29-1.31) for those born in the World War II and postwar period (1940-1949). Although indicators of a more advantaged early-life environment and higher educational level (college or higher) were associated with a lower incidence of dementia, these variables did not explain the association between birth cohort and dementia incidence, which remained when vascular risk factors were included and were similar by sex.

CONCLUSIONS AND RELEVANCE

Age-specific dementia incidence was lower in participants born after the mid-1920s compared with those born earlier. In this population, the decrease in dementia incidence may reflect societal-level changes or individual differences over the life course rather than early-life environment, as reflected through recalled childhood socioeconomic status and measured height, educational level, and later-life vascular risk.

Dabrafenib inhibits the growth of BRAF-WT cancers through CDK16 and NEK9 inhibition

Although the BRAF inhibitors dabrafenib and vemurafenib have both proven successful against BRAF-mutant melanoma, there seem to be differences in their mechanisms of action. Here, we show that dabrafenib is more effective at inhibiting the growth of NRAS-mutant and KRAS-mutant cancer cell lines than vemurafenib. Using mass spectrometry-based chemical proteomics, we identified NEK9 and CDK16 as unique targets of dabrafenib. Both NEK9 and CDK16 were highly expressed in specimens of advanced melanoma, with high expression of both proteins correlating with a worse overall survival. A role for NEK9 in the growth of NRAS- and KRAS-mutant cell lines was suggested by siRNA studies in which silencing was associated with decreased proliferation, cell cycle arrest associated with increased p21 expression, inhibition of phospho-CHK1, decreased CDK4 expression, and the initiation of a senescence response. Inhibition of CDK4 but not CHK1 recapitulated the effects of NEK9 silencing, indicating this to be the likely mechanism of growth inhibition. We next turned our attention to CDK16 and found that its knockdown inhibited the phosphorylation of the Rb protein at S780 and increased expression of p27. Both of these effects were phenocopied in NRAS- and KRAS-mutant cancer cells by dabrafenib, but not vemurafenib. Combined silencing of NEK9 and CDK16 was associated with enhanced inhibition of melanoma cell proliferation. In summary, we have identified dabrafenib as a potent inhibitor of NEK9 and CDK16, and our studies suggest that inhibition of these kinases may have activity against cancers that do not harbor BRAF mutations.

Disruption of NAD(+) binding site in glyceraldehyde 3-phosphate dehydrogenase affects its intranuclear interactions

AIM

To characterize phosphorylation of human glyceraldehyde 3-phosphate dehydrogenase (GAPDH), and mobility of GAPDH in cancer cells treated with chemotherapeutic agents.

METHODS

We used proteomics analysis to detect and characterize phosphorylation sites within human GAPDH. Site-specific mutagenesis and alanine scanning was then performed to evaluate functional significance of phosphorylation sites in the GAPDH polypeptide chain. Enzymatic properties of mutated GAPDH variants were assessed using kinetic studies. Intranuclear dynamics parameters (diffusion coefficient and the immobile fraction) were estimated using fluorescence recovery after photobleaching (FRAP) experiments and confocal microscopy. Molecular modeling experiments were performed to estimate the effects of mutations on NAD(+) cofactor binding.

RESULTS

Using MALDI-TOF analysis, we identified novel phosphorylation sites within the NAD(+) binding center of GAPDH at Y94, S98, and T99. Using polyclonal antibody specific to phospho-T99-containing peptide within GAPDH, we demonstrated accumulation of phospho-T99-GAPDH in the nuclear fractions of A549, HCT116, and SW48 cancer cells after cytotoxic stress. We performed site-mutagenesis, and estimated enzymatic properties, intranuclear distribution, and intranuclear mobility of GAPDH mutated variants. Site-mutagenesis at positions S98 and T99 in the NAD(+) binding center reduced enzymatic activity of GAPDH due to decreased affinity to NAD(+) (Km = 741 ± 257 μmol/L in T99I vs 57 ± 11.1 µmol/L in wild type GAPDH. Molecular modeling experiments revealed the effect of mutations on NAD(+) binding with GAPDH. FRAP (fluorescence recovery after photo bleaching) analysis showed that mutations in NAD(+) binding center of GAPDH abrogated its intranuclear interactions.

CONCLUSION

Our results suggest an important functional role of phosphorylated amino acids in the NAD(+) binding center in GAPDH interactions with its intranuclear partners.

Abstract 2006: Kinases and adaptive signaling contribute to drug resistance in BRAF mutant melanoma

Melanoma, the most lethal form of skin cancer, is marked by numerous genetic modifications, including point mutations as well as overexpression and deletion of genes. Intrinsic and acquired resistance to BRAF V600E targeted therapies (BRAFi) in metastatic melanoma patients further underscores the need for global profiling of melanoma circuitry at the functional level. Therefore, activity-based protein profiling (ABPP) and phosphoproteomics was carried out to decipher steady state differences in global signaling mechanisms in naïve and BRAFi resistant melanoma cell lines with BRAF V600E mutations.

Four cell lines (A375, 1205Lu, WM164 and WM793) were selected to evaluate different molecular backgrounds of BRAF mutation based on their PTEN status (either WT or null). For each cell type, both the naïve and BRAFi resistant lines were analyzed via ABPP as well as chemical labeling with tandem mass tags (TMT) prior to discovery phosphoproteomics. While the ABPP approach mined for kinases, phosphoproteomics identified STY phosphorylated peptides providing information on signaling via kinase substrates. LC-MS/MS discovery proteomics (RSLC and Q Exactive, Thermo) identified and relatively quantified all peptides observed in ABPP and TMT phosphoproteomics experiments. MaxQuant was used for data evaluation; preliminary statistical analyses were performed in Perseus to select significant differences for pathway mapping (GeneGO, Metacore) and follow up experiments using siRNA or pharmacological inhibition. Adaptive responses to combination treatment were also explored using the SysQuant workflow for quantitative expression analysis and phosphoproteomics. These experiments served as a basis for comparison for a pilot project of 12 metastatic tumors from BRAF mutant melanoma patients selected for comparison of good and poor survival outcomes.

ABPP measurements on different cell line models (A375, 1205Lu, WM793 and WM164) reveal significant differences in ATP uptake of proteins in the resistant cell line model compared to its naïve counterpart. For example, in the 1205Lu cell line several proteins including EGFR, p38alpha, DNA-PK formed an interconnected pathway. Overall we identified between 2,000-2,800 proteins in each cell line with ∼150 kinases. Isobaric labeling coupled to phosphoproteomics identified ∼1,600 quantifiable proteins with ∼4,000 phosphorylation sites. Phosphoproteomics revealed concomitant increase in phosphorylation levels of the substrates acted upon by kinases showing higher ATP uptake in ABPP measurements. For example, in 1205Lu BRAFi resistant cells, CDK1, CDK2 and DNA-PK showed higher ATP uptake and their substrates SSK1, DPYSL3, and vimentin showed higher phosphorylation levels.

The complementary nature of the two functional proteomics approaches provided holistic overview of signalling network in melanoma and enabled selection of targets for follow-up studies.

Citation Format: Ritin Sharma, Manali Phadke, David Britton, Ian Pike, Keiran Smalley, John M. Koomen. Kinases and adaptive signaling contribute to drug resistance in BRAF mutant melanoma. [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 2006. doi:10.1158/1538-7445.AM2015-2006

Abstract 1131: Disruption of the NAD+- binding site affects GAPDH interactions in the nuclei of cancer cells outside glucose metabolism

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal enzyme of the glycolytic pathway in cancer cells (the Warburg effect) which also performs signaling/regulatory functions in several cellular pathways including apoptosis and accelerated senescence. Multiple post-translational modifications, e.g., phosphorylation, acetylation, and nitrosylation, modulate functions and protein interactions of GAPDH in the cell. To assess the potential role of GAPDH as a molecular target within the cancer energy metabolism network, we (1) characterized structural elements of human GAPDH polypeptide pertinent to its intranuclear functions, and (2) evaluated mobility of nuclear GAPDH in cancer cells treated with chemotherapeutic agents. Using MALDI-TOF analysis, we identified novel phosphorylation sites within the NAD+-binding center of GAPDH at Y94, Ser98, and Thr99. We generated polyclonal antibody specific to phosphoThr99-containing peptide within GAPDH, and demonstrated accumulation of T99-phosphoGAPDH in the nuclear fractions of A549 cancer cells following the cytotoxic stress using 2D-Western blot analysis. Analysis of the extant crystal structures for human GAPDH and molecular modeling experiments indicated that T99 is adjacent to the NAD+-binding site. Molecular mechanics and dynamics experiments suggested that mutation of Thr99 may adversely affect the local geometry of the NAD+-binding cleft, and is likely to decrease affinity for NAD+. We performed site-mutagenesis of the functional domains in GAPDH, and estimated the enzymatic properties, intranuclear distribution, and intranuclear mobility of GAPDH mutated variants. Site-mutagenesis at positions S98 and T99 in the NAD+-binding center abrogated enzymatic activity of GAPDH due to decreased affinity to NAD+ (Km = 0.41±0.17 mM in T99I vs. 0.04±0.01 mM in wild type GAPDH). FRAP analysis showed that mutation in NAD+-binding center of GAPDH didn't disrupt its nuclear translocation after chemotherapeutic agents, but prevented intranuclear interactions. Molecular dynamics parameters of nuclear EGFP_GAPDH_WT before vs. after araC treatment were: t(1/2) = 0.12 vs. 1.09 sec, and diffusion coefficient D = 28.88 vs. 3.2 μm2/s. The same parameters for EGFP-GAPDH_T99I were: t(1/2) 0.39 vs. 0.68 sec, and D = 9.1 vs. 5.1 μm2/s. The studies on the functional consequences and a mechanism of Thr99 phosphorylation will open avenues to the rational design of modulators of GAPDH activity, an important target in anticancer therapy.

Citation Format: Evgeny Krynetskiy, Manali Phadke, Natalia Krynetskaia, Anurag Mishra, Carlos Barrero, Salim Merali, Scott A. Gothe. Disruption of the NAD+- binding site affects GAPDH interactions in the nuclei of cancer cells outside glucose metabolism. [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 1131. doi:10.1158/1538-7445.AM2015-1131

Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-β-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of α subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

Comparative efficacy of three measles vaccines in Indian children

A Comparative study of three types of measles vaccines was undertaken among 1005 children. Of these 527 were vaccinated with the Serum Institute of India (SII) vaccine, 230 with Schwarz (SC) and 248 were vaccinated with Edmonston-Zegreb (EZ) vaccine (imported from Zegreb). Though the majority of children reacted favourably with all the three vaccines (SII: 98.43%; SC: 93.40%; EZ: 93.0%) with a rise in titre, but the percentage of seroconversion was significantly higher with the SII vaccine (p < 0.01). The Schwarz and Edmonston Zagreb vaccines showed significantly less GM titre as compared with the other age group i.e. 9-12 months (p < 0.05). With Serum Institute of India (SII) vaccine the GM titres were almost similar in the different age groups. The overall GM titre obtained with the SII vaccine was significantly higher than the SC vaccine (p > 0.001) as well as the EZ vaccine (p > 0.001). It is of interest to note that among the infants, 22.5% children had measles antibody in them before vaccination.

Non enzymatic glycosylation of alpha-1-proteinase inhibitor of human plasma

Human plasma contains inhibitors, which control the activity of proteolytic enzymes. Alpha-1-proteinase inhibitor and alpha-2-macroglobulin are two of them present in high concentration in human plasma, which inhibit action of trypsin among other proteinases. The trypsin inhibitory capacity (TIC) of human plasma is observed to be decreased in pathological conditions like diabetes mellitus. The mechanisms of decrease in TIC was due to nonenzymatic glycosylation of alpha-1-proteinase inhibitor (A1PI). A1PI was partially purified from normal human plasma by steps involving ammonium sulphate precipitation, DEAE Sepharose CL6B chromatography, Concanavalin A Sepharose Chromatography and Sephadex G-100 Gel filtration. Purified inhibitor was glycosylated in vitro by incubating it with varying glucose concentrations, under nitrogen for different periods of time in reducing conditions. After glycosylation, the molecular weight of inhibitor increased from 52 kDa to 57 KDa because of binding with glucose molecules. The percent free amino groups in the protein decreased with increasing glucose concentration and days of incubation. The TIC of such modified inhibitor decreased significantly. Decrease in TIC was dependent on the glucose concentration and period of incubation used during in-vitro glycosylation of native inhibitor.