Citations

e17009 Background: Decreased circulating levels of ether lipids (glycerophospholipids with an ether-linked fatty alcohol, e.g. plasmalogens) have been observed in obesity, diabetes and cardiovascular disease. In vitro and in vivo studies suggest that ether lipids are anti-inflammatory and protective against obesity. A recent landmark study revealed that ether lipids can kill cancer cells through ferroptosis. However, the role of ether lipids in prostate cancer has not been thoroughly investigated despite the known association of dysregulated lipid metabolism with poorer clinical outcomes. The aim of this study was to assess the relationship between the circulating profiles of ether lipids and clinical outcomes in localised and metastatic prostate cancer. Methods: The profiles of ~150 ether lipids (8 lipid classes) in plasma lipidomic data from localised prostate cancer (389 men in Australia) and metastatic castration-resistant prostate cancer (mCRPC)(2 cohorts –147 men in USA, 128 men in Australia) were analysed for associations with disease progression or overall survival (OS). Open-access genomic data of mCRPC tumours (108 men, CbioPortal) were analysed for aberrations in genes associated with ether lipid metabolism in relation to clinical outcome. Results: Previously in these study cohorts, we had identified men with poorer prognosis based on their plasma lipidome and our validated sphingolipid signature. These men with poorer prognosis have lower plasma levels of ether lipids than those with better prognosis (t-test p < 0.05, localised disease – 110 ether lipids, mCRPC – 54 ether lipids). Decreased plasma levels of up to 46 ether lipid species were associated with higher rates of clinical relapse in localised disease (hazard ratio (HR) range 0.37-0.73, p-value range 0.006-0.049), shorter radiological progression-free survival in mCRPC (HR range 0.35-0.73, p-value range 0.00009-0.049), and shorter OS in mCRPC (HR range 0.33-0.79, p-value range 0.000004-0.0497). Chromosomal loss of tumour GNPAT, an essential gene in ether lipid synthesis, was associated with shorter OS in mCRPC (HR = 1.36, 95% CI 1.02-1.81, p = 0.03). Conclusions: Lower circulating levels of ether lipids were associated with worse prognosis in localised and metastatic prostate cancer, suggesting that these lipids are protective against disease progression. Further research is required to understand the role of ether lipids in disease progression, and to determine if modulation of ether lipid levels through supplementation is beneficial.

Abstract Background Ustekinumab (UST) is an approved treatment for adults with inflammatory bowel disease (IBD: Crohn’s disease [CD] and ulcerative colitis [UC]), psoriasis (PsO), and psoriatic arthritis (PsA). Here, we present pooled safety analyses in these approved indications of patients (pts) with active tuberculosis (TB) and opportunistic infections (OIs) through 5 years (yrs) of UST treatment. Methods Pooled data included 13 Phase 2/3 UST studies through 5 yrs of CD and PsO, 2 yrs of UC, and 1 yr of PsA. OIs were identified by clinician review. Herpes zoster (HZ) was evaluated separately. Event rates per 100 pt yrs (PYs) are presented. Concomitant immunomodulators/corticosteroids were permitted in IBD and PsA pts. All pts who received ≥1 UST dose were included. In IBD, placebo (PBO) pts included data up to the first UST dose for pts initially treated with PBO, or &gt;16 weeks after the last UST dose for UST pts who switched to PBO. Results Across all approved indications, 19 OIs including TB were reported, with rates in PBO of 0.40 and UST of 0.10 through 5 yrs in 13807 PYs of follow-up (Table 1); rates of HZ were 1.21 and 0.63, respectively. Of 19 OIs, 18 were in IBD pts and 1 in a PsO pt. Overall, 14/16 pts (12/13 UST) with OIs excluding TB were also receiving confounding concomitant medications. A total of 3 active TB cases (2 pts with CD and 1 pt with UC) were reported in PBO (n=2; 1 in a Hungarian CD pt 10 months after receiving last UST dose) and UST (n=1) pts (Table 1). One active TB case was reported in an asymptomatic South African CD pt treated with UST who had a positive QuantiFERON®-TB Gold test on routine screening and bronchial brushings positive for M. tuberculosis. Both CD pts completed TB treatment with disease resolution. The most common OIs were esophageal candidiasis (UST n=3; PBO n=2) and cytomegalovirus colitis (UST n=3; PBO n=1). Conclusion Rates of OIs, including active TB, in UST-treated pts were low across approved indications through up to 5 yrs with 13807 PYs of follow-up and not higher in UST pts vs PBO pts, suggesting no increased risk of OI with long-term UST treatment.

Abstract Background Despite over a decade of evidence, uptake of GLS into guidelines and practice has been slow. Age, BP, and software have been reported to influence GLS, and have led to uncertainty about defining the normal range (NR). As there have been software changes since the last meta-analysis, we sought to define NR in the current era. Methods Pubmed, Cochrane, and EMBASE were searched using the keywords “Left Ventricle”, “Normal global longitudinal strain”, and “Speckle tracking Echocardiography” and relevant synonyms from 2011. Studies were included if they reported GLS based on speckle tracking techniques, included at least 20 healthy individuals, and had up to date contact details available. Healthy was defined as lack of known disease. Platforms used included General Electric, Philips, Canon and Tomtec. The authors of 8 of the 12 studies (67% response) provided individual patient data. Linear regression was used to determine predictors of GLS. Results There were 2396 pts, mean age 42 years (range 18–92), weight 66±12kg, height 169±9cm, BSA 1.7±0.2m2, and SBP 120±13 mmHg. Normal range for GLS was 21.0±2.6%. In multivariable analysis age (β=-0.02, p<0.01), weight (β=-0.03, p<0.01), SBP (β=-0.01, p<0.01) and platform were associated with GLS. GLS tends to vary with extremes of age and BP (see Figure 1 and Figure 2). GLS vs Age group Conclusion Extremes of age and BP may lead to low GLS, but generally, GLS is <16% is abnormal. Acknowledgement/Funding None

Abstract Background Bacteremia caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-E) is associated with inadequate empirical therapy and substantial mortality in neutropenic patients. Strategies are needed to identify neutropenic patients at high risk of these infections. Methods From April 2014 to September 2016, we collected perianal swabs, both at admission and weekly thereafter, from patients undergoing hematopoietic stem cell transplantation (HSCT). Patients received prophylactic levofloxacin while neutropenic. Swabs were plated onto selective agar, colonies were identified and underwent antimicrobial susceptibility testing, and phenotypic ESBL testing and polymerase chain reaction for β-lactamase genes were performed on ceftriaxone-resistant Enterobacteriaceae. We then determined the prevalence of pre-transplant ESBL-E colonization and risk of ESBL-E bacteremia. Colonizing and bloodstream isolates from patients with ESBL-E bacteremia underwent multilocus sequence typing and pulsed-field gel electrophoresis. Results We analyzed 312 patients, including 212 allogeneic and 100 autologous HSCT recipients. Ten percent (31/312) of patients had pre-transplant ESBL-E colonization. Susceptibility rates of colonizing ESBL-E were: levofloxacin, 25%; cefepime, 9%; piperacillin-tazobactam, 84%; and meropenem, 97%. Of 31 patients colonized with ESBL-E pre-transplant, 10 (32%) developed ESBL-E bacteremia during their transplant admission, compared to 1 (0.4%) of 281 patients not colonized with ESBL-E (P &lt; .001). All bloodstream ESBL-E were levofloxacin-resistant and colonizing and bloodstream isolates from individual patients had identical genotypic profiles. Conclusions HSCT recipients who are colonized with levofloxacin-resistant ESBL-E pre-transplant and receive levofloxacin prophylaxis have high rates of bacteremia from their colonizing strain during neutropenia. Assessing for ESBL-E colonization in neutropenic patients could lead to optimization of empirical antibacterial therapy.