Citations

Abstract Eating disorders and substance use disorders frequently co‐occur. Twin studies reveal shared genetic variance between liabilities to eating disorders and substance use, with the strongest associations between symptoms of bulimia nervosa and problem alcohol use (genetic correlation [ r g ], twin‐based = 0.23‐0.53). We estimated the genetic correlation between eating disorder and substance use and disorder phenotypes using data from genome‐wide association studies (GWAS). Four eating disorder phenotypes (anorexia nervosa [AN], AN with binge eating, AN without binge eating, and a bulimia nervosa factor score), and eight substance‐use‐related phenotypes (drinks per week, alcohol use disorder [AUD], smoking initiation, current smoking, cigarettes per day, nicotine dependence, cannabis initiation, and cannabis use disorder) from eight studies were included. Significant genetic correlations were adjusted for variants associated with major depressive disorder and schizophrenia. Total study sample sizes per phenotype ranged from ~2400 to ~537 000 individuals. We used linkage disequilibrium score regression to calculate single nucleotide polymorphism‐based genetic correlations between eating disorder‐ and substance‐use‐related phenotypes. Significant positive genetic associations emerged between AUD and AN ( r g = 0.18; false discovery rate q = 0.0006), cannabis initiation and AN ( r g = 0.23; q < 0.0001), and cannabis initiation and AN with binge eating ( r g = 0.27; q = 0.0016). Conversely, significant negative genetic correlations were observed between three nondiagnostic smoking phenotypes (smoking initiation, current smoking, and cigarettes per day) and AN without binge eating ( r gs = −0.19 to −0.23; qs < 0.04). The genetic correlation between AUD and AN was no longer significant after co‐varying for major depressive disorder loci. The patterns of association between eating disorder‐ and substance‐use‐related phenotypes highlights the potentially complex and substance‐specific relationships among these behaviors.

Introduction: Interferon regulatory factor 4 (IRF4) is a transcription factor involved in B cell activation and differentiation into plasma cells, as well as B-cell lineage neoplasia. Diverse genetic abnormalities and dysregulated expression of IRF4 have been documented in various hematologic malignancies, including multiple myeloma (MM). IRF4 is also identified as a major downstream target of CRBN/IKZF to regulate MYC expression, representing a primary mechanism underlying anti-MM action of IMiDs. However, it remains unclear how the expression and function of IRF4 are regulated in MM cells. Materials and Methods: DNAseq, whole exome RNAseq (WES), and label-free analyses of quantitative proteomics and post-translational modifications (PTMs) mapping were conducted to examine genetic aberrations, transcriptional dysregulation, or protein and PTM alterations in primary patient samples and drug-naive vs -resistant cell lines. Flow cytometry, qPCR, and Western blot analysis were utilized to monitor apoptosis or mRNA and protein levels of target genes. Stable transfection with wild-type or mutated IRF4 was carried out to evaluate its function. Analysis of the MM genome-wide GEP databases (R2: Genomics Analysis and Visualization Platform) was performed to validate the clinical significance of IRF4 and its target genes in MM patients. Results: MM cells that acquired bortezomib (btz) resistance (PS-R) exhibited a marked increase in protein levels of multiple key components of the canonical and non-canonical NF-κB signaling cascades, in association with increased NF-κB transcriptional activity. Pharmacological inhibition of NF-κB using several compounds (e.g., Bay 11-7082, parthenolide, triptolide) significantly increased btz sensitivity in PS-R cells and their parental U266 cells, as well as other MM cell lines. These events were accompanied by down-regulation of various genes, including NF-κB-dependent genes and those whose relationship with NF-κB remains uncertain. The latter included IRF4, MYC, MCL1, BIRC2/cIAP1, SQSTM1/p62, among others. Of note, overexpression of wild-type IRF4 sharply reduced sensitivity of drug-naive cells to btz alone or in combination with NF-κB inhibitors. However, IRF4 overexpression did not prevent inactivation of NF-κB and down-regulation of the NF-κB-dependent genes (e.g., Bcl-xL, TNFAIP3/A20), suggesting that IRF4 acts downstream of NF-κB. Surprisingly, IRF4 overexpression failed to restore expression of MYC, a well-established target of IRF4, while largely reversed expression of cIAP1 and Mcl-1 at both mRNA and protein levels. Moreover, inhibitors of either IAP (birinapant/TL32711) or Mcl-1 (S63845) overcame btz-resistance conferred by IRF4 overexpression. DNAseq unveiled multiple IRF4 SNPs located in introns and exons (both 3'-UTR and coding region) of chromosome 6. WES revealed that IRF4 was highly expressed in primary bone marrow and extramedullary samples of MM patients (2~10 folds over normal donors). But no difference at mRNA and protein levels of IRF4 was observed between drug-naive and -resistant cell lines. The global PTM mapping identified two lysine residues (K59 and K399) that were highly ubiquitinated in PS-R cells (p = 0.0447 and p = 0.0004, vs U266 cells). Interestingly, ectopic expression of IRF4 mutants (e.g., K59N, K123R) lost the cytoprotective capability of their wild-type counterpart, in association with failure to reverse down-regulation of cIAP1 and Mcl-1. This observation argues that these point mutations are loss-of-function, which might explain better prognosis of patients carrying IRF4 mutations (including K59N and K123R) than wild-type IRF4 as reported previously. Last, the MM GEP database analysis validated the correlation between IRF4 and Mcl-1 or cIAP expression, as well as the adverse effect of their dysregulation on overall survival of MM patients. Conclusion: IRF4 is highly expressed in MM cells, likely via an NF-κB-dependent mechanism. IRF4 acts downstream of the NF-κB signaling pathways, which in turn directly targets cIAP1 and Mcl-1, rather than MYC, to confer drug resistance. IRF4 could be mutated in MM patients, while the point mutations, at least at certain lysine sites, seem to be loss-of-function and thus predict better outcome. Together, these findings suggest that the oncogenic function of IRF4 might be governed at genetic, transcriptional, and PTM levels in MM cells. Disclosures Kumar: Takeda: Research Funding; Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding.

Abstract Since researchers identified α-synuclein as the principal component of Lewy bodies and Lewy neurites, studies have suggested that it plays a causative role in the pathogenesis of dementia with Lewy bodies and other ‘synucleinopathies’. While α-synuclein dyshomeostasis likely contributes to the neurodegeneration associated with the synucleinopathies, few direct biochemical analyses of α-synuclein from diseased human brain tissue currently exist. In this study, we analysed sequential protein extracts from a substantial number of patients with neuropathological diagnoses of dementia with Lewy bodies and corresponding controls, detecting a shift of cytosolic and membrane-bound physiological α-synuclein to highly aggregated forms. We then fractionated aqueous extracts (cytosol) from cerebral cortex using non-denaturing methods to search for soluble, disease-associated high molecular weight species potentially associated with toxicity. We applied these fractions and corresponding insoluble fractions containing Lewy-type aggregates to several reporter assays to determine their bioactivity and cytotoxicity. Ultimately, high molecular weight cytosolic fractions enhances phospholipid membrane permeability, while insoluble, Lewy-associated fractions induced morphological changes in the neurites of human stem cell-derived neurons. While the concentrations of soluble, high molecular weight α-synuclein were only slightly elevated in brains of dementia with Lewy bodies patients compared to healthy, age-matched controls, these observations suggest that a small subset of soluble α-synuclein aggregates in the brain may drive early pathogenic effects, while Lewy body-associated α-synuclein can drive neurotoxicity.

TPS594 Background: Effective treatment options are very limited for patients with advanced refractory biliary tract cancer (BTC). Fluoropyrimidine-based chemotherapy regimen such as 5-fluorouracil and irinotecan are frequently utilized for these patients after first-line therapy despite lack of FDA approval. Trifluridine/tipiracil (FTD/TPI) is a novel oral nucleoside with antitumor activity in both fluoropyrimidine sensitive and resistant tumors due to its unique mechanisms of action. Given early toxicity and efficacy data from our previous study on single-agent trifluridine/tipiracil (FTD/TPI) in advanced BTC, the clinical evaluation of its combination with irinotecan represents a rational approach for the treatment of advanced refractory BTC. Methods: This is a single-arm phase II trial with a two-stage design to assess the efficacy of trifluridine/tipiracil (FTD/TPI) and irinotecan in advanced refractory BTC. Key eligibility criteria include histologically confirmed advanced, unresectable BTC who have progressed on at least one line of systemic therapy and have measurable disease per RECIST v1.1. Target accrual is 25. Treatment includes trifluridine/tipiracil (FTD/TPI) 25 mg/m2 on days 1-5 and irinotecan 180 mg/m2 on day 1 in 14-day cycles. Patients will be evaluated for response every 4 cycles and in the absence of disease progression, therapy may be given up to 2 years. The primary end point is the progression-free survival rate at 16 weeks. Secondary endpoints include overall response rate, disease control rate, progression-free survival, overall survival, and incidence of adverse events. Correlative biomarker studies include evaluations of circulating tumor DNA and circulating tumor cells at baseline, after 4 cycles and at progression; and development of patient-derived tumor organoids from pre-treatment biopsies for parallel treatments. This study was approved and funded in part by the National Comprehensive Cancer Network (NCCN) Oncology Research Program from general research support provided by Taiho Oncology, Inc. Clinical trial information: NCT 04072445.

204 Background: More than 50% of colorectal cancer (CRC) patients will develop metastatic disease. Brain metastasis (BM) from colorectal cancer is uncommon (0.6-1.36%). This study aims to investigate the patient characteristics, treatment modalities and prognostic factors in this rare population. Methods: 104 patients with brain metastasis disease from CRC were identified from over 30,000 colorectal cancer patients at the Mayo Clinic Rochester between 1/1994 and 6/2019. A retrospective review was conducted by using data from electronic medical records (EMR). Statistical analysis utilized the Kaplan-Meier method, Log-rank test, and Cox proportional hazards models. Results: Among the 104 patients, 62 were male (59.6%) and 42 were female (40.4%). Median age at CRC diagnosis was 58.4 and at BM diagnosis was 61. Thirty-three patients had right-sided colon cancers, 27 patients had left-sided colon cancers and 39 patients had rectal cancer. Median time from CRC diagnosis to BM was 30.7 months. The majority of patients (58.7%) presented with a solitary brain lesion. Eighty-six patients (82.7%) had extracranial metastatic disease at BM diagnosis. Median survival was 7.0 months (95% CI 2.6-16.9) from BM diagnosis. Age <70, solitary BM, surgery, radiation, and chemotherapy were associated with statistically significant improved survival on univariate and multivariate analysis. Multi-modality treatment including surgical brain lesion resection, postoperative stereotactic radiation (SRS) with/without whole brain radiation (WBRT), and chemotherapy significantly improved median overall survival (Table). Conclusions: Although BM from CRC carries poor prognosis, multi-modality treatment (surgery, radiation and systemic chemotherapy) for patients with limited BM improves clinical outcome. [Table: see text]

188 Background: Unplanned subgroup analyses from several studies have suggested primary tumor sidedness (PTS) as a potential prognostic and predictive parameter in metastatic colorectal cancer (mCRC). We aimed to investigate the prognostic and predictive impact of PTS on outcomes. Methods: PTS data of 7,828 mCRC patients (pts) from 10 first-line randomized trials in the ARCAD database were pooled. PTS was defined as right-sided (RS) or left-sided (LS) if tumor arose from the cecum to the hepatic flexure or from the splenic flexure to the rectum, respectively; transverse colon cancers were not included. Overall survival (OS) and progression-free survival (PFS) were assessed using Kaplan-Meier and Cox models adjusting for age, sex, performance status (PS), prior radiation/chemo, and stratified by treatment arm. Predictive value was tested by interaction term between PTS and treatment (anti-EGFR plus chemotherapy vs. chemotherapy alone). Results: Compared to RS pts (2407, 31%), LS pts (5421, 69%) had better OS (median: 21.6 v 16.8 mos; HRadj: 0.73, 95% CI 0.69-0.78, P < .001) and PFS (median 8.4 v 7.2 mos; HRadj: 0.81, 95% CI 0.76-0.86, P < .001). Results were consistent among subgroups defined by age, sex, PS, metastatic sites and chemo backbone (irinotecan- and oxaliplatin-based). Interaction between PTS and KRAS mutation was significant (Pinteraction< .001): LS is associated with better prognosis only among KRAS wild-type (wt) (HRadj: OS 0.62, 95% CI, 0.55-0.70; PFS 0.71, 95% CI 0.63-0.80), but not among KRAS mutated pts. Among KRAS wt pts, survival benefit from anti-EGFR was observed for LS, but not for RS (table). Conclusions: The prognostic value of PTS is restricted to the KRAS wt population. PTS is predictive of anti-EGFR efficacy, with a significant improvement of survival for LS mCRC pts. These results suggest treatment stratification in mCRC studies by both PTS and KRAS status. [Table: see text]

147 Background: Colorectal cancer is one of the leading causes of cancer related deaths with liver being most common site of CRC metastasis. More than 50% of the CRC patients will develop metastatic liver lesion that eventually leads to death in about 70% of them. In this retrospective review we reviewed the outcome of pts who received neoadjuvant chemotherapy followed by resection of liver lesion for metastatic colorectal cancer. Methods: 304 pts who had preoperative chemotherapy were identified from 1045 metastatic colorectal cancer patients who had liver metastasectomy at Mayo Clinic between 1997 and 2018. A retrospective review was conducted by using data from electronic medical records. Statistical analyses utilized Kaplan-Meier method, Log-rank test, and Cox proportional hazards models. Results: There were 113 (37%) female and 191 (63%) male pts. Median age at primary disease diagnosis was 56.5 yrs. Two hundred forty-nine pts presented with stage IV metastatic colorectal cancer. Primary tumor locations were: 53 right-sided, 117 left-sided and 133 rectum. 152 (50%) pts had extrahepatic metastases. Two pts were found to be MSI-H, 113 MSS, 189 unknown. BRAF mutation was found in 6 patients. RAS mutation was present in 84 patients, with 124 unknown. Pts received chemotherapy for median of 2.82 months. Single agent fluoropyrimidine was administered in 38 (12%) pts and rest receiving chemotherapy doublet or triplet with fluropyrimidine plus oxaliplatin being most common regimen. The median overall survival from primary diagnosis for the entire group was 74.5 months. Median overall survival from liver metastasectomy was 60.0 months. In univariate analysis, metachronous disease, age < 60 yrs, and an absence of extrahepatic lesions led to statistically significant improvement of overall survival from primary diagnosis. Metachronous and extrahepatic lesions remained statistically significant in multivariate analysis. Conclusions: Neoadjuvant chemotherapy followed by liver metastasectomy is beneficial for highly-selected metastatic colorectal cancer pts. Compared to a historical control of 30-36 months, our patient population had a median overall survival of about 5 years from resection.

Background The epidemiological transition of non-communicable diseases replacing infectious diseases as the main contributors to disease burden has been well documented in global health literature. Less focus, however, has been given to the relationship between sociodemographic changes and injury. The aim of this study was to examine the association between disability-adjusted life years (DALYs) from injury for 195 countries and territories at different levels along the development spectrum between 1990 and 2017 based on the Global Burden of Disease (GBD) 2017 estimates. Methods Injury mortality was estimated using the GBD mortality database, corrections for garbage coding and CODEm—the cause of death ensemble modelling tool. Morbidity estimation was based on surveys and inpatient and outpatient data sets for 30 cause-of-injury with 47 nature-of-injury categories each. The Socio-demographic Index (SDI) is a composite indicator that includes lagged income per capita, average educational attainment over age 15 years and total fertility rate. Results For many causes of injury, age-standardised DALY rates declined with increasing SDI, although road injury, interpersonal violence and self-harm did not follow this pattern. Particularly for self-harm opposing patterns were observed in regions with similar SDI levels. For road injuries, this effect was less pronounced. Conclusions The overall global pattern is that of declining injury burden with increasing SDI. However, not all injuries follow this pattern, which suggests multiple underlying mechanisms influencing injury DALYs. There is a need for a detailed understanding of these patterns to help to inform national and global efforts to address injury-related health outcomes across the development spectrum.