Research in the laboratory of Felipe Andrade, M.D., Ph.D., focuses on the mechanisms of systemic autoimmune diseases, particularly as they relate to the role of cytotoxic granule proteases in autoimmunity and viral clearance, mechanisms of autoantigen citrullination and pathways that control immune effector functions in autoimmune diseases. We currently focus on two principal areas: (1) defining the mechanisms that generate citrullinated autoantigens in vivo in rheumatoid arthritis and (2) understanding the pathways that control the activity of the peptidylarginine deiminase (PAD) enzymes in human neutrophils.

The Stivers Lab is broadly interested in the biology of the RNA base uracil when it is present in DNA. Our work involves structural and biophysical studies of uracil recognition by DNA repair enzymes, the central role of uracil in adapative and innate immunity, and the function of uracil in antifolate and fluoropyrimidine chemotherapy. We use a wide breadth of structural, chemical, genetic and biophysical approaches that provide a fundamental understanding of molecular function. Our long-range goal is to use this understanding to design novel small molecules that alter biological pathways within a cellular environment. One approach we are developing is the high-throughput synthesis and screening of small molecule libraries directed at important targets in cancer and HIV-1 pathogenesis.

The long-term goal of the Caren L. Freel Meyers Laboratory is to develop novel approaches to kill human pathogens, including bacterial pathogens and malaria parasites, with the ultimate objective of developing potential therapeutic agents. Toward this goal, we are pursuing studies of bacterial isoprenoid biosynthetic enzymes comprising the methylerythritol phosphate (MEP) pathway essential in many human pathogens. Studies focus on understanding mechanism and regulation in the pathway toward the development of selective inhibitors of isoprenoid biosynthesis. Our strategies for creating new anti-infective agents involve interdisciplinary research in the continuum of organic, biological and medicinal chemistry. Molecular biology, protein expression and biochemistry, and synthetic chemistry are key tools for our research.

The Frueh Laboratory uses nuclear magnetic resonance (NMR) to study how protein dynamics can be modulated and how active enzymatic systems can be conformed. Non-ribosomal peptide synthetases (NRPS) are large enzymatic systems that biosynthesize secondary metabolites, many of which are used by pharmaceutical scientists to produce drugs such as antibiotics or anticancer agents. Dr. Frueh's laboratory uses NMR to study inter- and intra-domain modifications that occur during the catalytic steps of NRPS. Dr. Frueh and his team are constantly developing new NMR techniques to study these complicated enzymatic systems.

Current research in the Sean T. Prigge Lab explores the biochemical pathways found in the apicoplast, an essential organelle found in malaria parasites, using a combination of cell biology and genetic, biophysical and biochemical techniques. We are particularly focused on the pathways used for the biosynthesis and modification of fatty acids and associated enzyme cofactors, including pantothenate, lipoic acid, biotin and iron-sulfur clusters. We want to better understand how the cofactors are acquired and used, and whether they are essential for the growth of blood-stage malaria parasites.

The Richard J. Jones Lab studies normal and cancerous stem cells in order to make clinical improvements in areas such as blood and marrow transplantation (BMT). We discovered one of the most common stem-cell markers, Aldefluor, which identifies cells based on their expression of aldehyde dehydrogenase 1 (ALDH1), and have used this marker to detect and characterize normal stem cells and cancer stem cells from many hematologic malignancies. We also developed post-transplant cyclophosphamide and effective related haploidentical BMT.

Normal and neoplastic cells respond to genome integrity threats in a variety of different ways. Furthermore, the nature of these responses are critical both for cancer pathogenesis and for cancer treatment. DNA damaging agents activate several signal transduction pathways in damaged cells which trigger cell fate decisions such as proliferation, genomic repair, differentiation, and cell death. For normal cells, failure of a DNA damaging agent (i.e., a carcinogen) to activate processes culminating in DNA repair or in cell death might promote neoplastic transformation. For cancer cells, failure of a DNA damaging agent (i.e., an antineoplastic drug) to promote differentiation or cell death might undermine cancer treatment. Our laboratory has discovered the most common known somatic genome alteration in human prostatic carcinoma cells. The DNA lesion, hypermethylation of deoxycytidine nucleotides in the promoter of a carcinogen-defense enzyme gene, appears to result in inactivation of the gene and a resultant increased vulnerability of prostatic cells to carcinogens. Studies underway in the laboratory have been directed at characterizing the genomic abnormality further, and at developing methods to restore expression of epigenetically silenced genes and/or to augment expression of other carcinogen-defense enzymes in prostate cells as prostate cancer prevention strategies. Another major interest pursued in the laboratory is the role of chronic or recurrent inflammation as a cause of prostate cancer. Genetic studies of familial prostate cancer have identified defects in genes regulating host inflammatory responses to infections. A newly described prostate lesion, proliferative inflammatory atrophy (PIA), appears to be an early prostate cancer precursor. Current experimental approaches feature induction of chronic prostate inflammation in laboratory mice and rats, and monitoring the consequences on the development of PIA and prostate cancer.

The Shanthini Sockanathan Laboratory uses the developing spinal cord as our major paradigm to define the mechanisms that maintain an undifferentiated progenitor state and the molecular pathways that trigger their differentiation into neurons and glia. The major focus of the lab is the study of a new family of six-transmembrane proteins (6-TM GDEs) that play key roles in regulating neuronal and glial differentiation in the spinal cord. We recently discovered that the 6-TM GDEs release GPI-anchored proteins from the cell surface through cleavage of the GPI-anchor. This discovery identifies 6-TM GDEs as the first vertebrate membrane bound GPI-cleaving enzymes that work at the cell surface to regulate GPI-anchored protein function. Current work in the lab involves defining how the 6-TM GDEs regulate cellular signaling events that control neuronal and glial differentiation and function, with a major focus on how GDE dysfunction relates to the onset and progression of disease. To solve these questions, we use an integrated approach that includes in vivo models, imaging, molecular biology, biochemistry, developmental biology, genetics and behavior.

Our lab is focused on using comprehensive gene expression, methylation and sequencing and metabolomics analysis to identify alterations in breast cancer, and exploiting these for early detection and therapy. Among deferentially expressed genes, our lab has focused on the HOX genes. HOX genes are intimately involved in the development of resistance to both chemotherapy and to agents targeting the estrogen receptor. Our work explores the alternate pathways that are activated by HOX proteins leading to this resistance and novel treatments to overcome resistance in both tissue culture and xenograft models. In addition, epigenetically silenced genes and a metabolic reprogramming in tumors also trigger novel early detection and therapeutic strategies. We are testing the utility of differentiation therapy through reactivating RAR-beta in breast cancer using histone deacetylase inhibitors with great success. Also, we are targeting enzymes involved in gluconeogenesis and glycolysis with small molecule FDA-approved antimetabolites to achieve antitumor effects.

Epstein-Barr virus and Kaposi's sarcoma herpesvirus are found in association with a variety of cancers. Our laboratory studies are aimed at better defining the role(s) of the virus in the pathogenesis of these diseases and the development of strategies to prevent, diagnose or treat them. We have become particularly interested in the unfolded protein response in activation of latent viral infection. Among the notions that we are exploring is the possibility that activation of virus-encoded enzymes will allow the targeted delivery of radation. In addition, we are investigating a variety of virus-related biomarkers including viral DNA, antibody responses, and cytokine measurements that may be clinically relevant.