L. Michael Carastro, Jr.
Associate Professor of Chemistry
Education:
- 1994 University of Tampa, B.S. in Biochemistry and Biology
- 2001 University of Miami School of Medicine, Ph.D. in Biochemistry and Molecular Biology
Postdoctoral Training and Faculty Appointments:
- 2001 Postdoctoral Fellow - The Salk Institute for Biological Studies
- 2002 Visiting Postdoctoral Fellow - H. Lee Moffitt Cancer Research Institute
- 2003 Postdoctoral Scholar - Penn State College of Medicine
- 2005 Assistant Professor of Pharmacology - Penn State College of Medicine
- 2007 Collaborator Member - H. Lee Moffitt Cancer Research Institute
Research Interests
Michael Carastro’s research interests are focused on the molecular etiology of human cancers, including the molecular mechanisms that maintain cellular DNA integrity and regulate gene expression. His early research work was in DNA replication/repair, but his dissertation research serendipitously progressed into a novel area of gene expression regulation, called nonsense-mediated mRNA decay (NMD). NMD is a translation-dependent mRNA degradation process that only targets mRNAs containing a translation termination codon recognized as “premature.” Carastro was primary author of a 2002 Nucleic Acids Research article that first reported a connection between cellular DNA replication (DNA polymerase delta) and the nonsense-mediated mRNA decay (NMD) helicase (HUPF1, helicase required for NMD). Since the initial discovery, other groups have published results following this pioneering work and/or cited it in review articles, including Current Opinion in Genetics and Development (Culbertson & Leeds, 2003), Nature Reviews Molecular Cell Biology (Maquat, 2004), Molecular Microbiology (de Pinto et al, 2004), Journal of Cell Science (Maquat, 2005), Molecular and Cellular Biology (Whittmann et al, 2006), Current Biology (Azzalin & Lingner, 2006), and Cell Cycle (Azzalin & Lingner, 2006).
In recent years, Carastro developed and directed two human cell culture-based prostate cancer (PCa) research projects: (1) epigenetic regulation of the TP73 tumor suppressor gene promoter and p73 protein isoform balance, and (2) molecular studies of cellular gene expression changes induced by exposure to Polyphenon E, a proprietary, standardized green tea extract that is rich in polyphenols and caffeine-free. With my research colleague, Dr. Jong Park (Moffitt Cancer Center), we investigated the molecular role of a dinucleotide polymorphism (DNP) in the TP73 tumor suppressor gene. This TP73 DNP project resulted in a peer-reviewed research article (Carastro et al, 2014). The essence of these published findings was the detection of a statistically significant decreased risk for aggressive PCa, as well as altered cellular p73 protein isoform levels, TAp73 and deltaNp73. Also, we worked to develop LC-MS proteomic methodologies, in consultation with the Moffitt Proteomics Core, to quantitatively detect and discriminate between the two p73 protein isoforms. Recently, we quantitatively analyzed the CpG methylated positions within the TP73 gene promoter using pyrosequencing methodologies. We have developed comprehensive, quantitative data that is consistent with a direct relationship between the degree (%) of methylation at specific CpG sites within the p73 gene promoter and the metastatic potential of PCa human cell lines studied. Our TP73 CpG promoter methylation studies are the subject of current research in my laboratory at UT.
Currently, Carastro’s laboratory is conducting molecular oncology studies using human PCa cell cultures treated with Polyphenon E (Poly E) in order to detect gene expression changes related to Poly E treatment of human PCa cells. Poly E is a To date, we have used three PCa cell lines (and normal, primary prostate cells) to generate DNA microarray data, as well as qRT-PCR and western blotting data. Some of these data using PC-3 PCa cells were recently published (Carastro et al, 2022) and included five UT undergraduate co-authors.
1. TP73 epigenetics and p73 protein isoform project - The epigenetic mechanisms regulating the gene expression of tumor suppressor gene TP73, the isoform balance of p73 proteins (TAp73 vs. deltaNp73), are being studied in Carastro's laboratory. Since we have identified and quantified the CpG methylation positions within the TP73 gene promoter, the next step in this project is to identify the involve (1) the translational repression imposed on messenger RNAs (mRNAs) by an upstream open reading frame (uORF) in the mRNA 5'-leader sequence, and (2) a cellular mRNA degradation process, called non-sense mediated mRNA decay (NMD), triggered by some uORF-translation.
2. Polyphenon E prostate cancer project – The potential chemopreventive properties of Polyphenon E, a caffeine-free standardized green tea extract rich in polyphenols, is being assessed using a human PCa cell model system. Human PCa cell cultures are treated with varied concentrations of Poly E, then protein and RNA are isolated from the cells. RNA samples used to measure gene expression changes (at the mRNA level) induced by Poly E treatments. The protein samples from Poly-E-treated cells are used to assess the gene expression changes (at the protein level) induced by Poly-E treatments.
Students working in Carastro’s research lab will be engaged in molecular oncology research and will be exposed to many biochemical and molecular biological techniques, including isolation of biological molecules (DNA, RNA, protein), analysis of biological molecules (DNA electrophoresis, PCR, quantitative real time-PCR, western blotting), and human cell culture techniques.
Prospective undergraduate research students for Carastro’s research laboratory need to meet two criteria: (1) voluntarily assist and/or shadow another upperclassman student researcher in the Carastro lab for at least 1 semester, and (2) successful completion of the Biochemistry (CHE320) course. Because I have a limited capacity to take undergraduate research students, and because taking an independent research course for credit is required for biochemistry majors, I typically only take undergraduate students majoring in biochemistry into my research laboratory, with some exceptions.
Peer-Reviewed Research Articles
Carastro, L.M., Tan, C.-K., So, A.G., and Downey, K.M. (2002) Identification of Delta Helicase as the Bovine Homologue of HUPF1: Demonstration of an Interaction with the Third Subunit of DNA Polymerase Delta. Nucleic Acids Res. 30, 2232-2243.
Lu, X., Tan, C.-K., Zhou, J.-Q., You, M., Carastro, L.M., Downey, K.M., and So, A.G. (2002) Direct Interaction of Proliferating Cell Nuclear Antigen with the Small Subunit of DNA Polymerase Delta. J Biol Chem. 277, 24340-24345.
Carastro, L.M., Tan, C.-K., So, A.G., and Downey, K.M. (2002) Delta helicase corresponds to KIAA0221: A link between DNA polymerase delta and RNA surveillance complex. Scientific World Journal 1 (Suppl 3), 77.
Strudwick, S., Carastro, L.M., Stagg, T., and Lazarus, P. (2003) Differential transcription-coupled translational inhibition of human p53 expression: A potentially important mechanism of regulating p53 expression in normal versus tumor tissue. Mol Cancer Res. 1, 463-474.
Joshi, B., Rastogi, S., Morris, M., Carastro, L. M., DeCook C., Seto, E. and Chellappan, S.P. (2007) Differential regulation of human YY1 and caspase 7 promoters by prohibitin through E2F1 and p53 binding sites. Biochem J. 401, 155-166.
Carastro, L.M., Gandikal, N., Brucklacher, R. and Lazarus P. (2007) An upstream open reading frame regulates p53 mRNA stability and translation. (Manuscript in preparation
Zhou, J.-Q., Tan, C.-K., Carastro, L.M., Downey, K.M., and So, A.G. The Small Subunit of DNA Polymerase Delta is a Counterpart of the Tau Subunit of the Escherichia coli DNA Polymerase III. Cold Spring Harbor Symposium on DNA Replication, Cold Spring Harbor, NY (September 1997).
Carastro, L.M., Tan, C.-K., So, A.G., and Downey, K.M. Delta Helicase, a DNA Helicase that Co-Purifies with DNA Polymerase Delta. 2000 Cancer Research Poster Session, University of Miami School of Medicine-Sylvester Comprehensive Cancer Center, Miami, FL (May 2000).
Carastro, L.M., Tan, C.-K., So, A.G., and Downey, K.M. Delta Helicase Corresponds to KIAA0221 (HUPF1): A Link Between DNA Polymerase Delta and RNA Surveillance Complex. 2001 Miami Nature Biotechnology Winter Symposium "Cell Death and Aging", Miami Beach, FL (February 2001).
Carastro, L.M., Tan, C.-K., So, A.G., and Downey, K.M. Delta Helicase Corresponds to KIAA0221 (HUPF1): A Link Between DNA Polymerase Delta and RNA Surveillance Complex. 2001 Eastern-Atlantic Student Research Forum of the American Medical Association, Miami, FL (February 2001).
Carastro, L.M., Tan, C.-K., So, A.G., and Downey, K.M. Delta Helicase Corresponds to KIAA0221 (HUPF1): A Link Between DNA Polymerase Delta and RNA Surveillance Complex. Experimental Biology 2001, Orlando, FL (March 2001).
Carastro, L.M. and Lazarus, P. Role of Putative Upstream Reading Frames in the Translational Regulation of p53 mRNA. 95th American Association for Cancer Research National Meeting, Orlando, FL (March 2004).
Carastro, L.M. and Lazarus, P. Translation of an Upstream Open Reading Frame in p53 mRNA Triggers mRNA Decay. 96th American Association for Cancer Research National Meeting, Anaheim, CA (April 2005).
Sun, D., Duncan, K., Chen, G., Dellinger, R, Carastro, L.M., and Lazarus, P. Glucuronidation of tamoxifen and 4-hydroxytamoxifen by human UGT1A4 variants. 96th American Association for Cancer Research National Meeting, Anaheim, CA (April 2005).
Sun, D., Duncan, K., Chen, G., Dellinger, R, Carastro, L.M., Weinberg, R.B., Zhong, Q., and Lazarus, P. Glucuronidation of the active metabolites of tamoxifen by human liver microsome and individual UDP-glucuronosyltransferases (UGTs). 97th American Association for Cancer Research National Meeting, Washington, D.C. (April 2006).
Carastro, L.M., Gandikal, N., and Brucklacher, R. An uORF in p53 mRNA regulates translation and uORF-containing p53 mRNA is selectively degraded by a translation- & PIKK-dependent mechanism. Salk/Cal Tech DNA Replication & Genomic Stability 2006, Salk Institute for Biological Studies, La Jolla, CA (August 2006)
Carastro, L.M., Gandikal, N., and Brucklacher, R. An uORF in p53 mRNA regulates translation and uORF-containing p53 mRNA is selectively degraded by a translation- & PIKK-dependent mechanism. Experimental Biology 2007, Washington, D.C. (April 2007)
