Robin J. Leach - US grants

Oculoauriculovertebral dysplasia (OAV) is a disorder characterized by ear malformations, jaw asymmetry, eye abnormalities and anomalies of the cervical spine. It has recently been shown that this disorder is autosomal dominantly inherited in some families (Kaye et al., 1990). The genetic basis for the malformations observed in patients with OAV is unknown. Clinical and experimental data have suggested candidate genes which may be involved in this dysplasia. Retinoic acid, a vitamin A metabolite, has been shown to produce craniofacial anomalies mimicking OAC in a high percentage of infants exposed to the agent in utero. The action of vitamin A and its metabolites appear to be mediated by three specific receptors in the developing embryo. A mutation in the gene coding for one of these receptors might be directly responsible for altered morphogenesis, such as is seen in patients with OAV. Alternatively, retinoic acid may induce other genes important in morphogenesis. Retinoic acid induces the expression of the homeobox (HOX) genes in embryonic carcinoma cells. The homeoboxes are a highly conserved gene family which were first identified as regulators of embryonic development in Drosophila melanogaster. By sequence homology, HOX genes have been isolated from both mouse and man. Experimental evidence from transgenic mice implies that an overexpression of one HOX gene, Hox-1.1, results in animals which have multiple craniofacial anomalies. These animals demonstrate a phenotype which mimics retinoic acid embryopathy and OAV. The basic defects of malformation syndromes are elusive. This dysplasia provides an opportunity to understand how an alteration in a single gene can produce such syndromes. By performing linkage analysis in OAV families with markers for the HOX and retinoic acid loci, we can determine if these genes are altered in OAV. Eight families of children with OAV will be studied. In each family, OAV is segregating in an autosomal dominant pattern. Thus these families are ideal for testing the role of these candidate genes in this disease. To begin this analysis, blood samples will be obtained from patients with OAV and from informative family members. Lymphoblastoid cell lines will be established from each sample. DNA will be isolated from the cell lines and analyzed with polymorphic markers from the candidate genes. These data will be utilized to establish the role of these genes in OAV. If linkage is established with the candidate genes under investigation, then future studies will focus on identification of specific mutations. If linkage is disproved, then future studies will focus on identification of other loci which are linked to the autosomal dominant gene in the families under investigation. The long term goal of the research is to identify an abnormal gene associated with craniofacial dysmorphogenesis and to elucidate its mutation.

Osteoporosis is defined as a rapid reduction in bone mass. With the growing longevity of the population, there is a substantial increase in the frequency of this disorder. Bones are in a constant state of remodeling which consists of two processes: bone resorption and bone formation, performed by the osteoclasts and osteoblasts, respectively. With age, the thickness of the born gradually declines, primarly because the osteoblasts are unable to keep pace with the osteoclasts. Determining the key regulatory mechanisms involved in maintaining the integrity of the osteoblast is important for understanding the aging process. This is a proposal to investigate the control of osteoblast-specific gene expression. A novel molecular/genetic experimental system will be utilized to investigate the regulation of four osteoblastic genes: estrogen receptor, bone Gla protein, matrix Gla protein and liver/bone/kidney alkaline phosphatase. A set of intertypic hybrids will be constructed between highly differentiated rat osteosarcomas and human fibroblasts. Genetic studies of this nature have been utilized to identify tissue-specific trans-dominant negative regulatory elements termed extinguishers in a number of experimental system. The goal of this project will be to identify and localize extinguishers which control the expression of osteoblast-specific genes. In addition, experiments are designed to identify the Cis sequences in the osteooblast-specific structural gene that are required for their regulation. By identifying and ultimately isolating these unique regulators, we can begin to understand their role in the development and maintenance of the osteoblast. Important insights can be gained into perturbations of these regulatory circuits which might occur in the osteoblast during aging.

The Human Genome Project is a concerted effort of the scientific community. In order for this project to be completed, it will require the development of new technologies and the optimization of old technology. Interspecific hybrids have been utilized for a number of years for gathering physical localization data. With the development of recent technology, it is apparent that interspecific hybrids are not only useful for mapping genes but for constructing physical maps of human chromosomes. We propose to utilize three types of interspecific hybrids to construct a physical map of human chromosome 2. The first type will be prepared from patients with known translocation breakpoints on human chromosome 2. These hybrids will be used to establish the framework for the map. The second class of hybrids will be constructed using microcell-mediated chromosome transfer. Microcell hybrids containing fragments of human chromosomes will be utilized to gather regional localization data. The third class of hybrids will be radiation-reduced hybrids. To construct these hybrids, microcell hybrids containing an intact human chromosome 2 will be irradiated and fused to rodent cells. All three classes of hybrids will be utilized to produce a physical map of human chromosome 2. In addition, the microcell hybrids and the radiation-reduced hybrids will serve as a useful source of DNA for constructing recombinant DNA libraries specific for any region of the chromosome.

DESCRIPTION: (Adapted from the applicant's abstract) This proposal requests support for the travel expenses of a group of investigators for the First and Second International Workshops on Human Chromosome 8. The First International Workshop will be held on May 1-3, 1993 in Vancouver, B.C., Canada. The purpose of this meeting is to survey and summarize a large body of information on gene and genomic mapping on Chromosome 8 which is now being obtained in a number of laboratories around the world. The meeting will cover 1) overview of the previous Chromosome 8 map; 2) the latest information on physical mapping, including yeast artificial chromosomes (YACs), cosmids, phage and plasmid clones, including information on both genomic and cDNA clones; 3) the latest information on genetic linkage mapping, including the Centre d'Etude du Polymorphisme Humain (CEPH) consortium and NIH framework maps; and 4) review of recent results on important disease genes which reside on this chromosome. The organizers of this meeting are Drs. Stephen Wood, Dennis Drayna, and Robin Leach. Drs. Wood and Drayna are Genome Data Base (GDB) Editors for Chromosome 8 and the results of this meeting will be immediately made available to the general scientific community through both the GDB and CEPH. The majority of the costs of this meeting are expected to be supported by applications now pending before the European Economic Community (EEC) and Canadian Medical Research Council (MRC) funding agencies. The Second International Chromosome 8 Workshop is scheduled to take place at Oxford in the United Kingdom during the summer of 1994. It will be organized by Drs. Nigel Spurr, Veronica Buckle, Dennis Drayna, and Robin Leach. The format of the Second Workshop will be similar to the first, and it is anticipated that many of the same individuals will participate.

DESCRIPTION: (Adapted from the applicant's abstract) This proposal requests support for the travel expenses of a group of investigators for the First and Second International Workshops on Human Chromosome 8. The First International Workshop will be held on May 1-3, 1993 in Vancouver, B.C., Canada. The purpose of this meeting is to survey and summarize a large body of information on gene and genomic mapping on Chromosome 8 which is now being obtained in a number of laboratories around the world. The meeting will cover 1) overview of the previous Chromosome 8 map; 2) the latest information on physical mapping, including yeast artificial chromosomes (YACs), cosmids, phage and plasmid clones, including information on both genomic and cDNA clones; 3) the latest information on genetic linkage mapping, including the Centre d'Etude du Polymorphisme Humain (CEPH) consortium and NIH framework maps; and 4) review of recent results on important disease genes which reside on this chromosome. The organizers of this meeting are Drs. Stephen Wood, Dennis Drayna, and Robin Leach. Drs. Wood and Drayna are Genome Data Base (GDB) Editors for Chromosome 8 and the results of this meeting will be immediately made available to the general scientific community through both the GDB and CEPH. The majority of the costs of this meeting are expected to be supported by applications now pending before the European Economic Community (EEC) and Canadian Medical Research Council (MRC) funding agencies. The Second International Chromosome 8 Workshop is scheduled to take place at Oxford in the United Kingdom during the summer of 1994. It will be organized by Drs. Nigel Spurr, Veronica Buckle, Dennis Drayna, and Robin Leach. The format of the Second Workshop will be similar to the first, and it is anticipated that many of the same individuals will participate.

DESCRIPTION (Adapted from the Applicant's Abstract): Paget disease of the bone is a common bone disease characterized by abnormal osteoclasts which are large, overactive, multinucleated and contain paramyxovirus-like nuclear inclusions. It is a relatively common disorder, with an estimated incidence of 3% in individuals over the age of 40. In the majority of patients, Paget disease is asymptomatic. The 5% of patients with symptoms have bone pain and a wide range of complications including increased fractures, deafness and neurological complications. The most devastating complication of Paget disease is malignant transformation of the bone. Although these transformations are rare, they contribute significantly to the morbidity and mortality of this disorder. The most frequent type of malignant transformation associated with Paget disease is osteosarcoma. In addition, Paget patients with osteosarcoma have a much worse prognosis than patients with osteosarcoma de novo. Osteosarcomas are believed to result from a series of genetic alterations which transform the osteoblast to a malignant state. Strong evidence that an important tumor suppressor gene involved in the regulation of the osteoblast lies on chromosome 18 has recently been generated (Dr. Marc Hansen's laboratory). Furthermore, the applicant (Dr. Leach) has generated genetic evidence that there is a locus for Paget disease in the same region of chromosome 18. Thus, the correlation between Paget disease and osteosarcoma has a strong molecular basis. It is hypothesized that this osteosarcoma tumor suppressor gene and the Paget predisposition gene are the same gene, or two tightly linked genes (i.e., a contiguous gene syndrome). The goal of this research is to identify this gene (or these genes) on chromosome 18 and begin to determine their role in both of these disorders. This proposal is part of an Interactive Research Project Grant (IRPG) developed to achieve this goal. Dr. Hansen's laboratory will utilize mitotic mapping methods in osteosarcomas, while Dr. Leach's laboratory will use meiotic mapping with numerous Paget disease kindreds. Identification of this gene (or these genes) is an important step towards the development of treatment for osteosarcoma and Paget disease.

DESCRIPTION (adapted from applicant's abstract): Dysmyelination of the central nervous system is a key feature in individuals with the 18q- syndrome, a syndrome that results from loss of chromosomal material from the long arm of chromosome 18. Other common findings in 18q- patients include mental retardation, developmental delay, and hearing impairment. Through the studies of over 40 patients with this syndrome, the investigators have established that the most common feature of this syndrome is dysmyelination. From molecular genetic experiments, they have identified a region on chromosome 18 that is missing in each patient with dysmyelination. This region is therefore the "critical region" for dysmyelination in this syndrome. The gene that codes for myelin basic protein (MBP) maps into this critical region on chromosome 18q. However, mouse models have demonstrated that loss of one copy of the MBP gene is not sufficient to cause dysmyelination in the mouse. Since the 18q- syndrome is a contiguous gene syndrome, they hypothesize that there is more than one gene that must be lost from this region in humans and mice to have dysmyelination. Thus to test this hypothesis, they propose to make a mouse model that is missing the region of the mouse genome that is homologous to the "critical region" they identified in their human studies. To construct this mouse model, they propose three specific aims. The first aim is to map the transcripts they have identified in the human critical region into the mouse genome. The second aim will be to develop a mouse model with a deletion of the "critical region" using the Cre/loxP system. The third aim will be to characterize the myelin in this mouse model using molecular, structural and functional assays. These experiments will help them gain insight into the mechanism of abnormal myelination in patients with 1 8qsyndrome. In addition, this mouse model will be an important tool for future studies that focus on identifying genes that affect patients with 18q- syndrome. The information from these studies could ultimately lead to therapeutic intervention for this disorder.

DESCRIPTION (provided by applicant): Prostate cancer is the most common non-dermatologic neoplasm in men, affecting about one man in six in his lifetime. The primary public health approach for control of this disease is currently early diagnosis and treatment, relying primarily on the Prostate Specific Antigen (PSA) blood test for detection. Unfortunately, for most men with a PSA above 4.0 ng/mL (the most commonly-applied upper limit of normal), no prostate cancer is found at biopsy while many cancers are found below this 'normal' level. We have previously observed in the 18,882-person Prostate Cancer Prevention Trial (PCPT), a National Cancer Institute-sponsored study, that in men who received the drug finasteride, an inhibitor of the five alpha reductase type 2 enzyme and a medication used to improve urination, PSA was a better predictor of presence of prostate cancer. The most important predictor of the presence of prostate cancer was the change in PSA after beginning finasteride: men whose PSA did not change or increased had an almost 3-fold greater risk of having prostate cancer than those whose PSA decreased by 65% or more. Our hypothesis, based on these previous observations, is that PSA velocity during a 3-month treatment with finasteride more accurately predicts presence or absence of prostate cancer. To demonstrate the clinical usefulness of this test, we will recruit 500 men with an intermediate (20-60%) risk of prostate cancer and who are planning to undergo prostate biopsy to receive 3 months of finasteride at 5 mg/day. We plan to use our PCPT prostate cancer risk calculator to determine prostate cancer risk and subject eligibility. These men will be randomized in a 4:1 fashion to finasteride or placebo, will have PSA testing monthly and after 3 months will undergo prostate biopsy. We will then evaluate PSA velocity during these three months of finasteride treatment as a biomarker of prostate cancer on biopsy. We will then characterize the operating characteristics of PSA and digital rectal examination before and after finasteride treatment as well as determine the independent diagnostic value of the 3-month finasteride PSA velocity when added to the other prostate cancer risk factors used in the PCPT prostate cancer risk calculator. We will also compare the performance of PSA with finasteride treatment in combination or in place of the PCPT Risk Calculator to other newly developed prostate cancer biomarkers including PCA3, [-2]ProPSA, and TMPRSS2:ERG and evaluate the independent predictive value of these additional prostate cancer biomarkers on the performance of the PCPT Risk Calculator. The long term goal of this project is to develop a new methodology to improve prostate cancer detection while reducing the number of unnecessary prostate biopsies, procedures that are associated with considerable cost as well as potential for risks including infection and bleeding.

DESCRIPTION (provided by applicant): The rapid evolution of sophisticated data-intensive technologies has created a growing need for well-trained informatics scientists and computational biologists particularly in the field of cancer research. An inter-institutional effor to support state-of-the art training in computational biology and bioinformatics in San Antonio has assembled an experienced group of faculty in order to develop a unique educational training program in bioinformatics and computational biology with an emphasis on the needs of the cancer research community. This program will provide opportunities for students and faculty at the University of Texas at San Antonio (UTSA), a minority serving institution, to gain relevant experience by interacting directly with cancer center members at the Cancer Therapy and Research Center (CTRC) at the University of Texas Health Science Center at San Antonio (UTHSCSA), an NCI designated Cancer Center. The interaction will also provide UTHSCSA cancer researchers with needed computational analysis and modeling assistance from quantitative scientists across both campuses. Additional opportunities will be provided for intensive short courses/workshops for computational biology training aimed for a mixed audience of biologists and quantitative scientists is also planned. Thus, a total of three programs are proposed that are all focused on education. The programs will include: 1) Computation Biology/Bioinformatics Graduate Education; 2) Paid Internship Program; and 3) Continuing Education Opportunities. A unique aspect of the proposal is the use of real data and research questions in cancer and health disparities to provide a context for the graduate education of program 1, the basic skill sets for participants in program 2, and the hands-on activities for the broader audience of program 3. This multifocal approach should strengthen the interaction between the cancer center and the minority servicing institution. These efforts will ultimately lead to the submission of an R25 application.

he goals of this program are to develop the institutional and curricular infrastructure to initiate and promote joint graduate degree programs for computationally oriented scientists who have an understanding of the disciplines related to cancer biology and issues related to health disparities research. The project supports a period of data gathering, course alignment, defining course objectives, and the curriculum mapping, development, and assessment necessary for creating bioinformatics and computational biology emphases and eventually joint degree programs. By adapting instructional materials already developed at UTHSCSA and making connections with the data and research problems of UTHSCSA cancer/health disparities researchers, the program with help faculty develop a computational, evidence-based approach to teaching about cancer biology and health disparities at UTSA. /initially. a bioinformatics concentration/track will beset up including the necessary course development for this new track.

? DESCRIPTION (provided by applicant): Prostate cancer is the most common non-cutaneous cancer in American men. In May of 2012, the U.S. Preventive Task Force recommended that serum prostate specific antigen (PSA) screening no longer be recommended as standard clinical practice. A factor contributing to this recommendation is that many prostate cancers diagnosed via PSA-screening are indolent disease that will never progress. Current American Urologic Association recommendations stress informed decision making. To this end, this Clinical Validation Center will address the following major unmet clinical needs: 1) Optimize serum PSA screening protocols to identify men with aggressive diseases and reduce screening and detection of men with low risk disease (aim 1); 2) Validate markers that distinguish indolent versus aggressive disease using serum, DNA, urine, and tissue markers (aims 1 and 2); 3) Enhancing risk assessment for informed decision for individual patients, improving their ability to determine if a biopsy is in their best interest; 4) Develop a risk assessment tool for men on active surveillance to assist patients and physicians with decision making regarding biopsy. The SABOR EDRN Clinical Validation Center, established in 2000, has a long history of development of new tests for prostate cancer and critically evaluating such tests to ensure that, if they are used in the clinic, patients benefit from their use. Using the 4000-man SABOR cohort with other established cohorts (e.g., SWOG PCPT and PASS), Phase II and III validation studies will be conducted to improve biomarker performance related to prostate cancer risk and long term disease outcomes. The first aim focuses on assessing long term performance of current biomarkers including PHI, PCA3 and TMPRSS2:ERG. Also proposed in this aim are validation studies of constitutional genetic variants that may identify men at greater cancer risk or who are more likely to have poor disease outcomes. In aim 2, tissue microarrays (TMAs) will be developed for validating published markers of prognosis. In addition, TMAs that allow evaluation of performance of new tissue-based markers in ethnical/racial diverse tumors will be constructed. For the third aim, the PCPT risk calculator will be refined and a new tool developed to help men on active surveillance determine if a surveillance biopsy is necessary. The Center will continue its work to provide carefully-collected samples from patients to other investigators to either help discover the tests of the future or to conduct studies to ensure that the tests trul help patients. In addition, the SABOR scientific personnel will continue to provide service in leadership positions of the EDRN to ensure that the entire Network accelerates toward the goal of successful early detection and cure of cancer.

Project Summary?Cancer Research Career Enhancement The Mays Cancer Center (MCC) Cancer Research Career Enhancement (CRCE) Core seeks to provide a continuous supply of well-trained cancer scientists performing state-of-the-art cancer research. The Core is led by Robin Leach, Ph.D., (PSP) Associate Director (AD) for Education and a member of the Cancer Center since its inception. The UT Health San Antonio (UT Health SA) is the largest academic Health Science Center for South Texas and includes Schools of Medicine, Nursing, Dentistry, Health Professions, and the Graduate School of Biomedical Sciences. The UT Health SA is designated by the U.S. Department of Education as a Hispanic- serving Institution and consistently ranks as one of the top schools in the U.S. for graduating Hispanic health care providers. The MCC at the UT Health SA places a high priority on education and mentoring, and does so both within the Cancer Center and by integrating and coordinating activities with existing programs at UT Health SA. The MCC has dedicated resources to cancer-related training and career development from high schoolers through early- stage faculty levels. During the last reporting period, the MCC has provided cancer research training for 51 high school students and 155 undergraduates in summer enrichment and training programs. MCC members have trained 115 M.S. and 147 Ph.D. level graduate students, 30 medical students (via an accredited medical school research electives course), 25 M.D./Ph.D. students, and 2 D.D.S./Ph.D. students. A total of 70 physicians have completed MCC?s fellowships in Hematology and Medical Oncology, Advanced Oncology Drug Development, Urologic Oncology and Pediatric Hematology-Oncology. In new activities, the CRCE Core has established an Office of Education at the MCC, revitalized an advisory MCC Education Committee, and established an Affiliate membership category for trainees. Importantly, the CRCE Core has augmented cancer-related research mentoring for early-stage faculty who are Associate Members of MCC, partnering the basic scientists with senior clinical faculty and the clinical scientists with senior basic science faculty. During the upcoming funding period, the Core will continue summer training in cancer research for high school through college students, and develop new training opportunities for middle school students. Importantly, most of these efforts will target opportunities for underrepresented populations. We will also leverage and expand the existing cancer-related education and training activities throughout UT Health SA. We will continue to support mentoring and career development among advanced trainees ? from fellows through early-stage faculty ? with an emphasis on fostering participation of underserved minorities to produce a more diverse cancer research workforce of the future.