Isoforms of the TAL1 transcription factor have different roles in hematopoiesis and cell growth

T-cell acute lymphoblastic leukemia (T-ALL) protein 1 (TAL1) is a central transcription factor in hematopoiesis. The timing and level of TAL1 expression orchestrate the differentiation to specialized blood cells and its overexpression is a common cause of T-ALL. Here, we studied the 2 protein isoforms of TAL1, short and long, which are generated by the use of alternative promoters as well as by alternative splicing. We analyzed the expression of each isoform by deleting an enhancer or insulator, or by opening chromatin at the enhancer location. Our results show that each enhancer promotes expression from a specific TAL1 promoter. Expression from a specific promoter gives rise to a unique 5' UTR with differential regulation of translation. Moreover, our study suggests that the enhancers regulate TAL1 exon 3 alternative splicing by inducing changes in the chromatin at the splice site, which we demonstrate is mediated by KMT2B. Furthermore, our results indicate that TAL1-short binds more strongly to TAL1 E-protein partners and functions as a stronger transcription factor than TAL1-long. Specifically TAL1-short has a unique transcription signature promoting apoptosis. Finally, when we expressed both isoforms in mice bone marrow, we found that while overexpression of both isoforms prevents lymphoid differentiation, expression of TAL-short alone leads to hematopoietic stem cell exhaustion. Furthermore, we found that TAL1-short promoted erythropoiesis and reduced cell survival in the CML cell line K562. While TAL1 and its partners are considered promising therapeutic targets in the treatment of T-ALL, our results show that TAL1-short could act as a tumor suppressor and suggest that altering TAL1 isoform's ratio could be a preferred therapeutic approach.

Progressive familial intrahepatic cholestasis-outcome and time to transplant after biliary diversion according to genetic subtypes

Background

Progressive familial intrahepatic cholestasis (PFIC) is a heterogeneous disease characterized by progressive cholestasis in early childhood. Surgical therapy aims at preventing bile absorption either by external or internal biliary diversion (BD). Several different genetic subtypes encode for defects in bile transport proteins, and new subtypes are being discovered ongoingly. Overall, the literature is scarce, however, accumulating evidence points to PFIC 2 having a more aggressive course and to respond less favorable to BD. With this knowledge, we aimed to retrospectively analyze the long-term outcome of PFIC 2 compared to PFIC 1 following BD in children at our center.

Methods

Clinical data and laboratory findings of all children with PFIC, who were treated and managed in our hospital between 1993 and 2022, were analyzed retrospectively.

Results

Overall, we treated 40 children with PFIC 1 (n = 10), PFIC 2 (n = 20) and PFIC 3 (n = 10). Biliary diversion was performed in 13 children (PFIC 1, n = 6 and 2, n = 7). Following BD, bile acids (BA) (p = 0.0002), cholesterol (p < 0.0001) and triglyceride (p < 0.0001) levels significantly decreased only in children with PFIC 1 but not in PFIC 2. Three out of 6 children (50%) with PFIC 1 and 4 out of 7 children (57%) with PFIC 2 required liver transplantation despite undergoing BD. On an individual case basis, BA reduction following BD predicted this outcome. Of the 10 children who had PFIC 3, none had biliary diversion and 7 (70%) required liver transplantation.

Conclusion

In our cohort, biliary diversion was effective in decreasing bile acids, cholesterol levels as well as triglycerides in the serum only in children with PFIC 1 but not PFIC 2. On an individual case level, a decrease in BA following BD predicted the need for liver transplantation.

Effect of Concurrent Proton Pump Inhibitors With Palbociclib Tablets for Metastatic Breast Cancer

BACKGROUND

Palbociclib is indicated for the treatment of hormone receptor positive (HR+) human epidermal growth factor receptor 2 negative (HER2-) metastatic breast cancer (MBC) in combination with an aromatase inhibitor or fulvestrant. Two retrospective studies found that concurrent proton pump inhibitor (PPI) use with palbociclib capsules significantly reduced progression free survival (PFS) versus patients without a PPI. Palbociclib tablets were released in 2020 without restriction on PPI use. No study to date has evaluated the combination of palbociclib tablets with concurrent PPI use.

METHODS

Patients were retrospectively evaluated after they received palbociclib tablets for the treatment of HR+ HER2- MBC in the first line setting with or without a PPI. Patients were assigned to the no PPI use arm if they never used a PPI and the PPI use arm if they used a PPI for >50% of the duration of palbocicib therapy. The primary endpoint was PFS. The secondary endpoints included overall survival (OS) and adverse events.

RESULTS

Eighty-two patients were identified; 50 in the no PPI use group and 32 in the PPI use group. The median PFS was 20.6 months (95% confidence interval [CI], 16.07 to not estimable) in the no PPI use arm versus 21.0 months (95% CI, 15.15 to not estimable) in the PPI use arm (P = 0.95). Median OS was not reached in either arm. Adverse effects did not differ between arms.

CONCLUSION

Use of a concurrent PPI with palbociclib tablets does not significantly reduce PFS in patients treated for HR+ HER2- MBC.

Abstract 5440: Deep-learning model for tumor type classification enables enhanced clinical decision support in cancer diagnosis

Background: Knowledge of a patient’s tumor type is essential for guiding clinical treatment decisions in cancer, but histologically-based diagnosis remains challenging for a subset of cancers. Genomic alterations are highly indicative of tumor type and can be used to build classifiers that predict diagnoses, but most genomic-based classification methods use whole genome sequencing (WGS) data which is not feasible for widespread clinical implementation at present. Clinical sequencing is typically performed using cancer gene panels that target individual mutations, often drivers, but previous tumor type classifiers developed using driver-based features alone perform poorly. We hypothesize that a classifier developed using state-of-the-art deep-learning methods and a sufficiently large training cohort would be able to overcome previous accuracy limitations and support the development of a clinically-relevant tumor type prediction model.

Methods: We present Deep Genome-Derived Diagnosis (GDD-ENS), an ensemble-based deep-learning tumor type classification method trained using data from cancer gene panel sequencing. We specifically use data from MSK-IMPACT, an FDA-authorized clinical sequencing assay that reports genomic alterations including mutations, indels, copy number alterations, and gene fusions across 505 cancer-associated genes. We aggregated a discovery cohort of 35,372 patients with solid tumors profiled with MSK-IMPACT across 38 common cancer types and used this set to generate 4,487 somatic mutation features for development.

Results: GDD-ENS achieves 78.8% accuracy on a held out validation cohort of 6971 patients. For the 71.9% of predictions assigned a high confidence by the model, accuracy increases to 92.7%, rivaling WGS-based models. We use Shapley Values to report prediction-specific feature importance, and aggregate them across cancer types to show GDD-ENS identifies known cancer type-genomic alteration trends. GDD-ENS also, with high accuracy, identifies patients with cancer types not included in the 38 common types using metrics derived from ensemble statistics. For patients where non-genomic information could further guide predictions, we implement a customizable prediction-specific adaptive prior distribution and report improved accuracy after adjusting predictions to account for features such as metastatic sample biopsy site. Finally, we apply GDD-ENS to a set of 1,123 patients with Cancers of Unknown Primary (CUP) and return high confidence predictions for 49% of these patients, in some cases matching predictions on CUP samples with diagnoses that were later confirmed through additional sampling and disease progression.

Conclusions: Integrating GDD-ENS into prospective clinical sequencing workflows will enable clinically-relevant tumor type predictions that can guide treatment decisions in real-time.

Citation Format: Madison Darmofal, Shalabh Suman, Gurnit Atwal, Jie-Fu Chen, Anna Varghese, Jason C. Chang, Anoop Balakrishnan Rema, Aijazuddin Syed, Quaid Morris, Michael Berger. Deep-learning model for tumor type classification enables enhanced clinical decision support in cancer diagnosis. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5440.

Methods for think-aloud interviews in health-related resource-use research: the PECUNIA RUM instrument

BACKGROUND

The think-aloud (TA) approach is a qualitative research method that allows for gaining insight into thoughts and cognitive processes. It can be used to incorporate a respondent's perspective when developing resource-use measurement (RUM) instruments. Currently, the application of TA methods in RUM research is limited, and so is the guidance on how to use them. Transparent publication of TA methods for RUM in health economics studies, which is the aim of this paper, can contribute to reducing the aforementioned gap.

METHODS

Methods for conducting TA interviews were iteratively developed by a multi-national working group of health economists and additional qualitative research expertise was sought. TA interviews were conducted in four countries to support this process. A ten-step process was outlined in three parts: Part A 'before the interview' (including translation, recruitment, training), Part B 'during the interview' (including setting, opening, completing the instrument, open-ended questions, closing), and part C 'after the interview' (including transcription and data analysis, trustworthiness).

CONCLUSIONS

This manuscript describes the step-by-step approach for conducting multi-national TA interviews with potential respondents of the PECUNIA RUM instrument. It increases the methodological transparency in RUM development and reduces the knowledge gap of using qualitative research methods in health economics.

Molecular Classification of Appendiceal Adenocarcinoma

PURPOSE

Appendiceal adenocarcinomas (ACs) are rare, histologically diverse malignancies treated as colorectal cancers despite having distinct biology and clinical behavior. To guide clinical decision making, we defined molecular subtypes of AC associated with patient survival, metastatic burden, and chemotherapy response.

PATIENTS AND METHODS

A comprehensive molecular analysis was performed in patients with AC to define molecular subtypes. Associations between molecular subtype and overall survival, intraoperative peritoneal cancer index, and first-line chemotherapy response were assessed adjusting for histopathologic and clinical variables using multivariable Cox proportional hazards, linear regression, and logistic regression models.

RESULTS

We defined distinct molecular lineages of mucinous appendiceal adenocarcinoma (MAAP) from co-occurring mutations in GNAS, RAS, and TP53. Of 164 MAAP tumors, 24 were RAS-mutant (mut) predominant (RAS-mut/GNAS-wild-type [wt]/TP53-wt) with significantly decreased mutations and chromosomal alterations compared with tumors with GNAS mutations (GNAS-mut predominant) or TP53 mutations (TP53-mut predominant). No patient with RAS-mut predominant subtype metastatic MAAP died of cancer, and overall survival in this subgroup was significantly improved compared with patients with GNAS-mut (P = .05) and TP53-mut (P = .004) predominant subtypes. TP53-mut predominant subtypes were highly aneuploid; increased tumor aneuploidy was independently (P = .001) associated with poor prognosis. The findings retained significance in patients with any metastatic AC. RAS-mut predominant metastases exhibited reduced peritoneal tumor bulk (P = .04) and stromal invasion (P < .001) compared with GNAS-mut or TP53-mut predominant tumors, respectively. Patients with RAS-mut predominant MAAP responded more to first-line chemotherapy (50%) compared with patients with GNAS-mut predominant tumors (6%, P = .03).

CONCLUSION

AC molecular patterns identify distinct molecular subtypes: a clinically indolent RAS-mut/GNAS-wt/TP53-wt subtype; a chemotherapy-resistant GNAS-mut predominant subtype; and an aggressive, highly aneuploid TP53-mut predominant subtype. Each subtype exhibits conserved clinical behavior irrespective of histopathology.

Effect of oxybutynin and reboxetine on obstructive sleep apnea: a randomized, placebo-controlled, double blind, crossover trial

STUDY OBJECTIVES

Although recent investigations combining noradrenergic and antimuscarinic drugs have shown promising short-term results to treat obstructive sleep apnea (OSA), the mid-term effect and optimal dosage remain uncertain. The present study aimed to evaluate the effect of one week of 5 mg oxybutynin and 6 mg reboxetine (oxy-reb) on OSA versus placebo.

METHODS

We performed a randomized, placebo-controlled, double-blind, crossover trial comparing the effect of one week of oxy-reb versus one week of placebo on OSA severity. At-home polysomnography was performed at baseline and after each week of intervention.

RESULTS

Fifteen participants (male 66.7%) aged 59 [44-62] years (median [interquartile range]) with a mean body mass index of 33.1 ± 6.6 kg.m -2 were included. No significant difference in apnea-hypopnea index (AHI) was observed between conditions (estimated marginal means (95% confidence interval) at baseline: 39.7 (28.5-55.3); oxy-reb: 34.5 (22.7-52.3); placebo: 37.9 (27.1-52.9); p=0.652), but oxy-reb improved average oxygen desaturation (p=0.016) and hypoxic burden (p=0.011) and lowered sleep efficiency (p=0.019) and rapid eye movement (REM) sleep (p=0.002). Moreover, participants reported reduced sleep quality during the week of oxy-reb compared to the week of placebo (4.7 (3.5; 5.9) vs. 6.5 (5.5; 7.5) on a 0-10 visual analogic scale, respectively; p=0.001). No significant differences in sleepiness, vigilance and fatigue were observed. No serious adverse events occurred.

CONCLUSION

Administration of oxybutynin 5 mg and reboxetine 6 mg did not improve OSA severity assessed by AHI, but did alter sleep architecture and sleep quality. Reduced average oxygen desaturation and hypoxic burden were also observed.

Exploring the effectiveness of demand-side retail pharmaceutical expenditure reforms : Cross-country evidence from weighted-average least squares estimation

Increasing expenditures on retail pharmaceuticals bring a critical challenge to the financial stability of healthcare systems worldwide. Policy makers have reacted by introducing a range of measures to control the growth of public pharmaceutical expenditure (PPE). Using panel data on European and non-European OECD member countries from 1990 to 2015, we evaluate the effectiveness of six types of demand-side expenditure control measures including physician-level behaviour measures, system-level price-control measures and substitution measures, alongside a proxy for cost-sharing and add a new dimension to the existing empirical evidence hitherto based on national-level and meta-studies. We use the weighted-average least squares regression framework adapted for estimation with panel-corrected standard errors. Our empirical analysis suggests that direct patient cost-sharing and some-but not all-demand-side measures successfully dampened PPE growth in the past. Cost-sharing schemes stand out as a powerful mechanism to curb PPE growth, but bear a high risk of adverse effects. Other demand-side measures are more limited in effect, though may be more equitable. Due to limitations inherent in the study approach and the data, the results are only explorative.

Abstract P4-02-18: Impact of clonal hematopoiesis on disease progression following CDK4/6 inhibitor therapy

Background Clonal Hematopoiesis (CH) is a well-established risk factor for adverse clinical outcomes including all-cause mortality, cardiovascular disease, and progression to hematologic malignancies. The presence of CH has been shown to adversely impact overall survival in non-hematologic cancers, however whether CH modulates response to specific therapies in breast cancer is not known. Here we investigate the impact of CH mutations on disease progression in patients with metastatic estrogen receptor (ER) positive breast cancer undergoing treatment with first line CDK4/6 inhibitors and endocrine therapy (CDK4/6i+ET). Methods We analyzed data from a well annotated cohort of patients with ER+ breast cancer who received endocrine therapy and CDK4/6 inhibitors. All patients underwent prospective tumor and matched WBC sequencing utilizing the MSK-IMPACT assay. CH variants were detected in blood samples utilizing the well-validated variant detection and filtration pipeline of MSK-IMPACT. CH mutations were defined as putative drivers (CH-PD) or non-putative drivers (CH) as previously described. To ensure the presence of CH at the time of therapy initiation, only patients who had CH sampling performed from 6 months before through 4 months after initiation of CDK4/6i+ET were included. We compared progression free survival (PFS) in patients with and without CH, as well as by CH-PD status and DNMT3A CH mutations. We investigated clinical covariates including type of endocrine therapy, receipt of prior neoadjuvant or adjuvant chemotherapy, and age at start of CDK4/6i+ET. Results The final cohort was comprised of 378 patients, of whom 135 (35.7%) had CH. The median time between sample collection and CDK4/6i+ET initiation was 0 (IQR -0.79 to 0.47 months). Patients with CH were older at time of therapy initiation (median 63.0 versus 54.7 years, p &lt; 0.001). There were no significant differences between groups in terms of endocrine therapy (aromatase inhibitor or fulvestrant), prior chemotherapy, and time from CH sample collection to CDK4/6i+ET start. Univariate Cox-proportional hazard analysis did not reveal a difference between progression free survival and overall CH (HR 0.96, 95% CI 0.75 – 1.23, p = 0.76), CH-PD (HR 1.05, 0.77 – 1.43, p = 0.77), or DNMT3A mutations (HR 1.12, 0.80 – 1.60, p = 0.52) compared to patients without CH. Interestingly, age less than 60 years was found to be associated with PFS outcome (univariate HR 1.57, 1.22 – 2.01, p = 0.0004). Multivariate analysis adjusted for endocrine therapy partner and age at CDK4/6i+ET therapy did not reveal an association between outcome and overall CH (HR 1.07, 0.83 – 1.39, p = 0.59). In patients younger than age 60, presence of overall CH did not confer a significant PFS difference (HR 0.90, 0.63 – 1.29, p = 0.57). In the subset of patients older than 60 (n = 168) presence of CH conferred numerically, but not statistically, significant shorter PFS (HR 1.41 [0.96 – 2.09], p = 0.08). In this population, CH-PD conferred a shorter PFS (HR 1.75, 1.12 – 2.72, p = 0.02). Conclusion We found that CH, CH-PD and DNMT3A CH mutations did not affect PFS among metastatic ER+ breast cancer patients treated with first line CDK4/6 inhibitors. Younger age was associated with increased risk of progression, warranting further investigation. In the subset of patients with age older than 60, CH-PD conferred a shorter PFS. Further data, incorporating records of dose reductions, will be presented at the meeting.

Citation Format: Jacqueline Tao, Pablo Sanchez Vela, Anton Safonov, Emanuela Ferraro, Sebastia Franch Exposito, Kamal Menghrajani, Ryan Ptashkin, Elizabeth Comen, Lior Z. Braunstein, Mark E. Robson, Sarat Chandarlapaty, Jorge Reis-Filho, Michael Berger, Ahmet Zehir, Larry Norton, Ross Levine, Pedram Razavi. Impact of clonal hematopoiesis on disease progression following CDK4/6 inhibitor therapy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-02-18.

Abstract OT2-01-11: ctDNA-guided Adaptive Therapy Escalation in ER+ MBC: A Phase 1b Study with Letrozole, Palbociclib and Onapristone ER

ctDNA-guided Adaptive Therapy Escalation in ER+ MBC: A Phase 1b Study with Letrozole, Palbociclib and Onapristone ER Background: Extended release onapristone (onapristone ER) is a progesterone receptor (PR) antagonist that inhibits hormone-mediated PR activation and stabilizes PR association with corepressors, resulting in an antineoplastic effect when applied alone or in combination with antiestrogen therapy to breast cancer cells in vitro. Recent preclinical studies further suggest that onapristone adds to inhibition of cell proliferation when combined with CDK4/6 inhibitors and fulvestrant. Elevations in ctDNA can precede overt disease progression by a matter of months in metastatic breast cancer and may represent an opportunity for proactive therapeutic intervention. Trial Design: This is an investigator initiated open-label, single institution phase 1b study of onapristone ER added as escalation therapy in patients with ER+, PR+, HER2 negative MBC, who have detectable ctDNA after six months of treatment with letrozole and palbociclib in the first line. The study is supported by Context Therapeutics and involves two stages. Stage 1 is a dose escalation/de-escalation phase of 18 patients maximum, in which the safety and recommended phase 2 dose (RP2D) will be established for onapristone ER when used in combination with letrozole and palbociclib. In stage 2, the dose expansion phase, the RP2D of onapristone will be combined with letrozole and palbociclib in 10 patients to further explore the tolerability of the regimen. ctDNA will be collected serially while patients are on this triplet therapy. Eligibility Criteria: This study is enrolling patients with radiologically measurable or evaluable metastatic or unresectable ER+/PR+/HER2-negative MBC in whom a tumor-derived somatic mutation can be detected in ctDNA at a variant allele fraction of 0.5% or greater after 6 months (+/- 4 weeks) of treatment with first line letrozole and palbociclib without progression, using our in house CLIA certified MSK-ACCESS assay. Adequate organ function and functional status for enrollment are stipulated in the protocol. Specific Aims: The primary objective of this study is to define the safety, tolerability, and recommended phase 2 dose of onapristone ER used in combination with letrozole and palbociclib. Secondary objectives include to investigate ctDNA response rate of the triplet therapy regimen, to gather early data regarding the 6-month clinical benefit rate, overall response rate, and progression free survival of this triplet escalation therapy regimen in high risk ctDNA+ patients, and to evaluate the pharmacokinetics of Onapristone ER when used in combination with letrozole and Palbociclib. Exploratory objective include to describe ctDNA dynamics during antiprogestin therapy escalation in ER+ MBC, as well as the molecular features present in responders vs. non-responders using ctDNA and pre-treatment tissue. Target Accrual: The total planned cohort for the phase I dose escalation is a maximum of 18 patients across 3 dose levels, and the total planned cohort for the dose expansion is 10 patients, with an anticipated maximum total of 28 patients. We will allot for 5 additional patients to account for inevaluability during the dose escalation and expansion portions of the trial. The trial is currently open to enrollment at MSKCC. Contact Information: Dragoj@mskcc.org; Jhaverik@mskcc.org

Citation Format: Joshua Drago, Elaine Walsh, Mithat Gonen, Michael Berger, Mark E. Robson, Sarat Chandarlapaty, Pedram Razavi, Komal Jhaveri. ctDNA-guided Adaptive Therapy Escalation in ER+ MBC: A Phase 1b Study with Letrozole, Palbociclib and Onapristone ER [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT2-01-11.

No pain, no strain: Targin® mitigates pain and constipation following spinal cord injury

BACKGROUND

Opioids effectively reduce chronic pain, but present significant side effects including opioid-induced constipation. Oxycodone/naloxone decreases pain and constipation in cancer patients, however its effect on spinal cord injury population remains understudied.

METHODS

We assessed whether oxycodone/naloxone reduces pain, constipation, and severity of autonomic dysreflexia in an individual with spinal cord injury. A 55-year-old male with C5 lesion presented with chief complaint of chronic pain received 5/2.5 mg and 20/10 mg oxycodone/naloxone for 6 and 2 weeks, respectively.

RESULTS

Oxycodone/naloxone improved pain, bowel function, and autonomic dysreflexia severity.

INTERPRETATION

Oxycodone/naloxone was effective in managing chronic pain and constipation in the studied case.

The experiences of pediatric nurses deployed to adult COVID-19 wards

BACKGROUND

The coronavirus pandemic created an unprecedented deployment of health professionals. The objective of this study was to describe the experiences of pediatric nurses transferred to adult COVID-19 wards during the first wave of the pandemic.

METHODS

We performed a qualitative study using a phenomenological approach. Nurses were recruited on a voluntary basis. All participants moved from a pediatric ward and were redeployed to an adult COVID-19 ward in another hospital. Interviews were carried out face to face in line with social-distancing guidelines. We used a script of open-end questions. The interviews were recorded and transcribed in full and qualitative data were analyzed using NVivo software.

RESULTS AND CONCLUSIONS

In total, 23 nurses were interviewed. Our analysis revealed positive and negative experiences given the different types of support the nurses received, individual attitudes that promoted resilience in a crisis situation, ethical conflicts linked to end-of-life care, and their perspectives on the next wave of the pandemic. The main difficulties encountered by the transferred nurses were related to their working conditions and safety, communication about working practices, and end-of-life patient care. In most cases, the individual resilience strategies put in place and the different forms of social support enabled them to cope with stress and maintain their commitment. However, some interviewees would have benefited from improved managerial support. For all participants, their perception of this support and the benefits of their experience influenced their willingness to be transferred to an adult ward again during a future wave of the pandemic.

NBN Pathogenic Germline Variants are Associated with Pan-Cancer Susceptibility and In Vitro DNA Damage Response Defects

PURPOSE

To explore the role of NBN as a pan-cancer susceptibility gene.

EXPERIMENTAL DESIGN

Matched germline and somatic DNA samples from 34,046 patients were sequenced using Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets and presumed pathogenic germline variants (PGV) identified. Allele-specific and gene-centered analysis of enrichment was conducted and a validation cohort of 26,407 pan-cancer patients was analyzed. Functional studies utilized cellular models with analysis of protein expression, MRN complex formation/localization, and viability assessment following treatment with γ-irradiation.

RESULTS

We identified 83 carriers of 32 NBN PGVs (0.25% of the studied series), 40% of which (33/83) carried the Slavic founder p.K219fs. The frequency of PGVs varied across cancer types. Patients harboring NBN PGVs demonstrated increased loss of the wild-type allele in their tumors [OR = 2.7; confidence interval (CI): 1.4-5.5; P = 0.0024; pan-cancer], including lung and pancreatic tumors compared with breast and colorectal cancers. p.K219fs was enriched across all tumor types (OR = 2.22; CI: 1.3-3.6; P = 0.0018). Gene-centered analysis revealed enrichment of PGVs in cases compared with controls in the European population (OR = 1.9; CI: 1.3-2.7; P = 0.0004), a finding confirmed in the replication cohort (OR = 1.8; CI: 1.2-2.6; P = 0.003). Two novel truncating variants, p.L19* and p.N71fs, produced a 45 kDa fragment generated by alternative translation initiation that maintained binding to MRE11. Cells expressing these fragments showed higher sensitivity to γ-irradiation and lower levels of radiation-induced KAP1 phosphorylation.

CONCLUSIONS

Burden analyses, biallelic inactivation, and functional evidence support the role of NBN as contributing to a broad cancer spectrum. Further studies in large pan-cancer series and the assessment of epistatic and environmental interactions are warranted to further define these associations.

International comparability of reference unit costs of education services: when harmonizing methodology is not enough (PECUNIA project)

BACKGROUND

Health problems can lead to costs in the education sector. However, these costs are rarely incorporated in health economic evaluations due to the lack of reference unit costs (RUCs), cost per unit of service, of education services and of validated methods to obtain them. In this study, a standardized unit cost calculation tool developed in the PECUNIA project, the PECUNIA RUC Template for services, was applied to calculate the RUCs of selected education services in five European countries.

METHODS

The RUCs of special education services and of educational therapy were calculated using the information collected via an exploratory gray literature search and contact with service providers.

RESULTS

The RUCs of special education services ranged from €55 to €189 per school day. The RUCs of educational therapy ranged from €6 to €25 per contact and from €5 to €35 per day. Variation was observed in the type of input data and measurement unit, among other.

DISCUSSION

The tool helped reduce variability in the RUCs related to costing methodology and gain insights into other aspects that contribute to the variability (e.g. data availability). Further research and efforts to generate high quality input data are required to reduce the variability of the RUCs.

Human SLFN5 and its Xenopus Laevis ortholog regulate entry into mitosis and oocyte meiotic resumption

The Schlafen gene family was first described in mice as a regulator of thymocyte development. Further studies showed involvement of human orthologs in different processes related with viral replication, cellular proliferation, and differentiation. In recent years, a new role for human Slfn11 in DNA replication and chromatin remodeling was described. As commonly observed in many gene families, Slfn paralogs show a tissue-specific expression. This made it difficult to reach conclusions which can be valid in different biological models regarding the function of the different Schlafen proteins. In the present study, we investigate the involvement of SLFN5 in cell-cycle regulation and cell proliferation. A careful analysis of SLFN5 expression revealed that SLFN5 is highly expressed in proliferating tissues and that the protein is ubiquitously present in all the tissues and cell line models we analyzed. Very interestingly, SLFN5 expression oscillates during cell cycle, peaking during S phase. The fact that SLFN5 interacts with protein phosphatase 2A and that SLFN5 depletion causes cell cycle arrest and cellular apoptosis, suggests a direct involvement of this human paralog in cell cycle progression and cellular proliferation. We substantiated our in vitro and in cellulo results using Xenopus laevis oocytes to show that mRNA depletion of the unique Slfn gene present in Xenopus, whose protein sequence shares 80% of homology with SLFN5, recapitulates the phenotype observed in human cells preventing the resumption of meiosis during oocyte development.

Abstract B026: Chromatin profiles classify castration-resistant prostate cancers suggesting therapeutic targets

In castration-resistant prostate cancer (CRPC), the loss of androgen receptor (AR) dependence leads to clinically aggressive tumors with few therapeutic options. We used ATAC-seq (assay for transposase-accessible chromatin sequencing), RNA-seq, and DNA sequencing to investigate 22 organoids, six patient-derived xenografts, and 12 cell lines. We identified the well-characterized AR-dependent and neuroendocrine subtypes, as well as two AR-negative/low groups: a Wnt-dependent subtype, and a stem cell–like (SCL) subtype driven by activator protein–1 (AP-1) transcription factors. We used transcriptomic signatures to classify 366 patients, which showed that SCL is the second most common subtype of CRPC after AR-dependent. Our data suggest that AP-1 interacts with the YAP/TAZ and TEAD proteins to maintain subtype-specific chromatin accessibility and transcriptomic landscapes in this group. Together, this molecular classification reveals drug targets and can potentially guide therapeutic decisions.

Citation Format: Fanying Tang, Duo Xu, Shangqian Wang, Chen Khuan Wong, Alexander Martinez-Fundichely, Cindy Lee, Sandra Cohen, Jane Park, Corinne Hill, Kenneth Eng, Rohan Bareja, Teng Han, Eric Minwei Liu, Ann Palladino, Wei Di, Dong Gao, Wassim Abida, Shaham Beg, Loredana Puca, Maximiliano Meneses, Elisa De Stanchina, Michael Berger, Anuradha Gopalan, Lukas Dow, Juan Miguel Mosquera, Himisha Beltran, Cora Sternberg, Ping Chi, Howard Scher, Andrea Sboner, Yu Chen, Ekta Khurana. Chromatin profiles classify castration-resistant prostate cancers suggesting therapeutic targets [abstract]. In: Proceedings of the AACR Special Conference: Cancer Epigenomics; 2022 Oct 6-8; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_2):Abstract nr B026.

A systematic review and meta-analysis of patient-reported outcomes following nerve transfer surgery for brachial plexus injury

OBJECTIVE

The purpose of this systematic review and meta-analysis was to determine the effect of nerve transfer surgery for brachial plexus injury (BPI) on patient-reported outcomes.

LITERATURE SURVEY

MEDLINE, EMBASE, and CINAHL were searched and screened in duplicate for relevant studies on September 25, 2019 and repeated June 24, 2020.

METHODOLOGY

The patient population included male and female patients who received nerve transfer surgery for BPI. Further inclusion criteria were: (1) all levels of evidence; (2) published in English; (3) conducted in humans; and (4) report of patient-reported outcome. Two reviewers independently abstracted data regarding injury type, surgical technique, surgical timing, follow-up duration, strength, and patient-reported outcome measures. Quality was assessed in duplicate using the Methodological Index for Non-Randomized Studies criteria.

SYNTHESIS

Twenty-one studies involving 464 participants were included in analyses. The mean age ± SD was 32.4 ± 1.8 (range: 5-77) and 89.2% of included participants were male. The mean time to surgery was 5.6 ± 0.6 months and the mean follow-up time was 48.1 ± 8.4 months. The most used patient-reported outcome was the Disabilities of Arm, Shoulder and Hand (DASH), where scores variably improved postoperatively, although the degree of disability remained high. Return to work was reported in five studies, with 66.0% of participants returning to work. Patient satisfaction was assessed in four studies with an overall satisfaction proportion of 64.0%. Pain was assessed in 12 studies using various measures. In studies reporting pain intensity postoperatively, 29.3% of patients were "pain-free" or had "no pain."

CONCLUSIONS

Patient-reported outcomes following nerve transfer for BPI are infrequently reported in the literature. Although patient-reported outcomes demonstrate variable postoperative improvement, there is evidence of ongoing limitations and postoperative DASH scores report a high degree of ongoing disability. Future studies with greater reporting as well as validation of patient-reported outcomes within BPI are warranted.