Background: Current standard-of-care technologies such as imaging and cyst fluid analysis are unable to consistently distinguish intraductal papillary mucinous neoplasms of the pancreas (IPMN) at high-risk of pancreatic cancer from low-risk IPMN. The objective was to create a single-platform assay to identify IPMN that are at high-risk for malignant progression. Study Design: Building on the Verona International Consensus Conference BD-IPMN biomarker study, specific protein, cytokine, mucin, DNA, and miRNA cyst fluid targets were identified for creation of a q-PCR based assay as we have previously published. This included mRNA markers: ERBB2,

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SELENOF is a member of the class of selenoproteins in which the amino acid selenocysteine is co-translationally inserted into the elongating peptide in response to an in-frame UGA codon located in the 3′-untranslated (3′-UTR) region of the SELENOF mRNA. Polymorphisms in the 3′-UTR are associated with an increased risk of dying from prostate cancer and these variations are functional and 10 times more frequent in the genomes of African American men. SELENOF is dramatically reduced in prostate cancer compared to benign adjacent regions. Using a prostate cancer tissue microarray, it was previously established that the reduction of SELENOF in the cancers from African American men was significantly greater than in cancers from Caucasian men. When SELENOF levels in human prostate immortalized epithelial cells were reduced with an shRNA construct, those cells acquired the ability to grow in soft agar, increased the ability to migrate in a scratch assay and acquired features of energy metabolism associated with prostate cancer. These results support a role of SELENOF loss in prostate cancer progression and further indicate that SELENOF loss and genotype may contribute to the disparity in prostate cancer mortality experienced by African American men.

Objective The broad goal of the research described in this study was to investigate the contributions of selenium‐binding protein 1 (SBP1) loss in prostate cancer development and outcome. Methods SBP1 levels were altered in prostate cancer cell lines and the consequences on oxygen consumption, expression of proteins associated with energy metabolism, and cellular transformation and migration were investigated. The effects of exposing cells to the SBP1 reaction products, H 2 O 2 and H 2 S were also assessed. In silico analyses identified potential HNF4α binding sites within the SBP1 promoter region and this was investigated using an inhibitor specific for that transcription factor. Results Using in silico analyses, it was determined that the promoter region of SBP1 contains putative binding sites for the HNF4α transcription factor. The potential for HNF4α to regulate SBP1 expression was supported by data indicating that HNF4α inhibition resulted in a dose‐response increase in the levels of SBP1 messenger RNA and protein, identifying HNF4α as a novel negative regulator of SBP1 expression in prostate cancer cells. The consequences of altering the levels of SBP1 were investigated by ectopically expressing SBP1 in PC‐3 prostate cancer cells, where SBP1 expression attenuated anchorage‐independent cellular growth and migration in culture, both properties associated with transformation. SBP1 overexpression reduced oxygen consumption in these cells and increased the activation of AMP‐activated protein kinase (AMPK), a major regulator of energy homeostasis. In addition, the reaction products of SBP1, H 2 O 2 , and H 2 S also activated AMPK. Conclusions Based on the obtained data, it is hypothesized that SBP1 negatively regulates oxidative phosphorylation (OXPHOS) in the healthy prostate cells by the production of H 2 O 2 and H 2 S and consequential activation of AMPK. The reduction of SBP1 levels in prostate cancer can occur due to increased binding of HNF4α, acting as a transcriptional inhibitor to the SBP1 promoter. Consequently, there is a reduction in H 2 O 2 and H 2 S‐mediated signaling, inhibition of AMPK, and stimulation of OXPHOS and building blocks of biomolecules needed for tumor growth and progression. Other effects of SBP1 loss in tumor cells remain to be discovered.

Sickle cell disease (SCD) is caused by a mutation in the β-globin gene resulting in a disease that affects more than 100,000 Americans and millions worldwide. Though pain is the hallmark of SCD, patients also suffer damage to most organ systems. Sickle cell hemoglobin (HbS) polymerization occurs when deoxygenated, rendering red blood cells rigid and fragile. Production of excessive reactive oxygen species (ROS) and intracellular hypoxia in RBCs further accelerates the pathology associated with SCD. Recently, vaso-occlusive crisis (VOC) and organ damage were established to be strongly associated with oxidative stress in RBCs. This occurs when there is an increase in oxidants that exceeds the cellular anti-oxidant defenses. Excessive ROS can trigger a cascade of oxidative reactions that damage membrane lipids, and essential enzymatic antioxidants such as GPx-1, ultimately leading to hemolysis and multi-organ dysfunction. ROS generation in RBCs of SCD patients is due to factors such as HbS auto-oxidation and potentially aberrant mitochondrial function. We recently determined that red blood cells obtained from SCD mice and SCD patients retain their mitochondria compared to control subjects. Mitochondria retained SCD RBCs are also associated with elevated levels of ROS and hemolysis. Oxidative stress in the RBCs of SCD patients may be elevated by lower levels of antioxidant proteins such as the selenium-dependent enzyme GPX1. GPX1 was first described as an enzyme capable of protecting hemoglobin from ROS and has been reported to be lower in the RBCs in SCD. Selenium levels are lower among African Americans in the Chicago area and elsewhere. In this regard, it is notable that in the United States, African Americans represent the majority of those with SCD. To investigate the relationship between selenium levels and SCD, we have utilized a mouse model of SCD to examine the impact of a reduced intake of selenium on parameters associated with SCD pathology. SCD mice on a selenium-deficient diet (<0.01 mg/kg diet) were compared to mice fed with a selenium-adequate diet (0.1mg/kg). SCD mice in the selenium-deficient group exhibited an increase in mitochondria retaining RBCs (Se deficient: 26%±6.9%, n=3 vs. Se adequate: 5 % ± 3.5%, n=3, p<0.01), reduced Hb levels (Se deficient 5.7± 0.17 g/dl, n=3 vs. Se adequate 7.0± 0.83 g/dl, n=4 p<0.05), and an increased RBC oxygen consumption rate (OCR). These results support the hypothesis that low selenium status likely results in reduced levels of anti-oxidant selenoproteins and enhanced SCD severity. Disclosures Lavelle: Global Blood therapeutics: Research Funding.