djw@bu.edu

Cell Signaling and Gene Regulation Cancer Biology Biochemistry Endocrinology and Reproductive Biology

Professor of Cell and Molecular Biology, Dept of Biology
Professor of Medicine, Boston University School of Medicine
Ph.D., Harvard University, 1980

Molecular endocrinology and cell signaling; Cancer gene therapy and pharmacology; Liver genes and transcriptional control; Orphan receptors and responses to foreign chemicals

Humans, like other mammals, are exposed to a large number of toxic foreign chemicals, many of which are lipophilic and have a tendency to persist in fatty tissues. In response to this environmental challenge, mammals have evolved a large number of genes which encode cytochromes P450 and other enzymes that oxygenate lipophilic foreign compounds. Expression of these genes is controlled by a complex array of molecular regulatory circuits that respond to varying physiological conditions and changes in hormonal and environmental stimuli. In addition to metabolizing foreign chemicals, P450 enzymes hydroxylate physiological substrates, such as steroid hormones, arachidonic acid and cholesterol, which both compete with drug and other foreign chemical substrates and can regulate P450 metabolism through the modulation of P450 gene expression.

A major goal of our laboratory is to elucidate these metabolic processes at both the biochemical level and the molecular regulatory level. One of our research projects involves the regulation of liver P450 gene expression by the temporal pattern of pituitary growth hormone (GH) release. Other ongoing studies concern the regulation of these enzymes and their genes by factors such as thyroid hormone, circadian rhythms and non-genotoxic carcinogens classified as peroxisome proliferators. A second important goal of our laboratory is to identify ways through which our understanding of P450 biochemistry and gene regulation may be applied to improve human health. These efforts are exemplified by our development of cytochrome P450 as a model for cancer gene therapy using drug-susceptibility genes. P450 genes have great promise for applications designed to enhance the sensitivity of tumor cells to cancer chemotherapeutic drugs.

Current areas of major research emphasis include:

1) liver P450 gene regulation by endocrine factors;
2) growth hormone signaling
3) the role of P450 in anti-cancer drug pharmacology; and
4) the importance of nuclear receptors in the response of P450s to foreign chemicals.

These studies require an interdisciplinary approach, with emphasis on techniques drawn from molecular biology, cell biology, biochemistry and pharmacology. Model systems utilized include intact animal models (rat liver model, gene knockout mice, immunodeficient scid mice), cell culture models, and in vitro biochemicals studies, including the use of human liver microsomes and cDNA-expressed enzyme systems. Primary emphasis is placed on the following areas of research:

Endocrine control of hepatic P450 gene expression: cellular and molecular mechanisms. These studies are designed to elucidate the molecular basis for the developmental and sex dependent regulation of hepatic P450 genes. Current research projects investigate: (a) the molecular mechanisms by which the ultraradian pattern of growth hormone secretion can either masculinize hepatic enzyme expression (pulsatile pituitary growth hormone secretion) or feminize enzyme expression (continuous growth hormone secretion); (b) the role of the plasma membrane growth hormone receptor in growth hormone signaling and its activation of STAT proteins, signal transducers and activators of transcription which undergo tyrosine phosphorylation followed by nuclear translocation in response to growth hormone pulses; (c) thyroid hormone regulation of NADPH P450 reductase at the transcriptional and post-transitional levels; and (d) regulation of liver gene expression by PPAR and other orphan receptors that belong to the steroid receptor gene superfamily and respond to structurally diverse drugs and environmental chemicals.

Molecular pharmacology of P450 enzymes and their roles in anti-cancer drug and foreign chemical metabolism. Current research projects in the area of P450 pharmacology and toxicology include the following: (a) development of improved strategies for cancer therapy using P450 genes to sensitize tumor cells to cancer chemotherapeutic prodrugs (P450-based cancer gene therapy); (b) role of cytochrome P450 in the bioactivation of clinically useful anti-cancer drugs, with an emphasis on enzymes expressed in human liver; and (c) therapeutic and toxicological consequences of the modulation of P450 enzyme profiles in response to foreign chemical exposure.

PUBLICATIONS

2008

Ma J, Waxman DJ. 2008. Modulation of the antitumor activity of metronomic cyclophosphamide by the angiogenesis inhibitor axitinib. Mol Cancer Ther. 2008 Jan;7(1):79-89.

2007

Ma J, Waxman DJ. 2007. Collaboration between hepatic and intratumoral prodrug activation in a P450 prodrug-activation gene therapy model for cancer treatment. Mol Cancer Ther. 2007 Nov;6(11):2879-90.

Chen CS, Jounaidi Y, Su T, Waxman DJ. 2007. Enhancement of intratumoral cyclophosphamide pharmacokinetics and antitumor activity in a P450 2B11-based cancer gene therapy model. Cancer Gene Ther. 2007 Dec;14(12):935-44.

Clodfelter KH, Miles GD, Wauthier V, Holloway MG, Zhang X, Hodor P, Ray WJ, Waxman DJ. 2007. Role of STAT5a in regulation of sex-specific gene expression in female but not male mouse liver revealed by microarray analysis. Physiol Genomics. 2007 Sep 19;31(1):63-74.

Ma X, Idle JR, Malfatti MA, Krausz KW, Nebert DW, Chen CS, Felton JS, Waxman DJ, Gonzalez FJ. 2007. Mouse lung CYP1A1 catalyzes the metabolic activation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP).   Carcinogenesis 28, 732-737.

Holloway MG, Cui Y,   Laz EV, Hosui A, Hennighausen L, Waxman DJ.  2007. Loss of sexually dimorphic liver gene expression upon hepatocyte-specific deletion of Stat5a-Stat5b locus.   Endocrinology 148, 1977-1986.

Laz EV, Holloway MG, Chen CS, Waxman DJ.2007. Characterization of three growth hormone-responsive transcription factors preferentially expressed in adult female liver. Endocrinology. 2007 Jul;148(7):3327-37.

Gu J, Chen CS, Wei Y, Fang C, Xie F, Kannan K, Yang W, Waxman DJ, Ding X. 2007.  A mouse model with liver-specific deletion and global suppression of the NADPH-cytochrome P450 reductase gene:   characterization and utility for in vivo studies of cyclophosphamide disposition.   J Pharm Exp Therap 321, 9-17.

Sun L, Chen CS, Waxman DJ, Liu H, Halpert JR, Kumar S. 2007.  Re-engineering cytochrome P450 2B11dH for enhanced metabolism of several substrates including the anti-cancer prodrugs cyclophosphamide and ifosfamide.   Arch Biochem Biophys 458, 167-174.

2006

Kaya T, Mohr SC, Waxman DJ, Vajda S.   2006. Computational screening of phthalate monoesters for binding to PPARgamma.   Chem Res Toxicol. 19: 999-1009.

Clodfelter KH, Waxman DJ, Vajda S.   2006. Computational solvent mapping reveals the importance of local conformational changes for broad substrate specificity in mammalian cytochromes P450.   Biochemistry. 45: 9393-9407.

Park SH, Wiwi CA, Waxman DJ.   2006. Signalling cross-talk between hepatocyte nuclear factor 4alpha and growth-hormone-activated STAT5b.   Biochem J. 397: 159-168.

Chang TK, Waxman DJ.   2006. Synthetic drugs and natural products as modulators of constitutive androstane receptor (CAR) and pregnane X receptor (PXR).   Drug Metab Rev. 38: 51-73. Review.

Gunther M, Waxman DJ, Wagner E, Ogris M.   2006. Effects of hypoxia and limited diffusion in tumor cell microenvironment on bystander effect of P450 prodrug therapy.   Cancer Gene Ther. 13: 771-779.

Clodfelter KH, Holloway MG, Hodor P, Park SH, Ray WJ, Waxman DJ. Sex-dependent liver gene expression is extensive and largely dependent upon signal transducer and activator of transcription 5b (STAT5b): STAT5b-dependent activation of male genes and repression of female genes revealed by microarray analysis.   2006. Mol Endocrinol. 20: 1333-1351.

Shipley JM, Waxman DJ. Aryl hydrocarbon receptor-independent activation of estrogen receptor-dependent transcription by 3-methylcholanthrene.   2006. Toxicol Appl Pharmacol. 213: 87-97.

Waxman DJ, O'connor C. 2006. Growth Hormone Regulation of Sex-dependent Liver Gene Expression. Mol Endocrinol. March 16.

Holloway MG, Laz EV, Waxman DJ.   2006. Co-dependence of GH-responsive, sexually dimorphic hepatic gene expression on STAT5b and HNF4a.   Molec Endocrinol, Mar;20(3):647-60.

Cheung C, Yu A-M, Chen CS, Krausz KW, Byrd L, Feigenbaum L, Edwards RJ, Waxman DJ, Gonzalez FJ.   2006. Growth hormone determines sexual dimorphism of human P450 3A4 expression in transgenic mice. J Pharmacol Exp Ther, 316, 1328-1344.

Jounaidi Y, Chen CS, Veal GJ, Waxman DJ.   2006. Enhanced anti-tumor activity of P450 prodrug-based gene therapy using the low Km cyclophosphamide 4-hydroxylase P450 2B11.   Molec Cancer Therapy, Mar;5(3):541-55.

Roy P, Waxman DJ.   2006. Activation of oxazaphosphorines by cytochrome P450:   application to gene-directed enzyme prodrug therapy for cancer. Toxicol In Vitro 20, 176-186.

2005

Landsman T, Waxman DJ.   2005. Role of the cytokine-induced SH2-containing protein CIS in growth hormone receptor internalization.   J Biol Chem 280, 37471-37480.

Lu H, Waxman DJ.   2005. Anti-tumor activity of methoxymorpholinyl doxorubicin:   potentiation by cytochrome P450 3A metabolism. Molec Pharmacol 67, 212-219.

Wiwi CA, Waxman DH. 2005. Role of hepatocyte nuclear factors in transcriptional regulation of male-specific CYP2A2 . J Biol Chem 280, 3259-3268.

Sheu SH, Kaya T, Waxman DJ, Vajda S. 2005. Exploring the binding site structure of the PPARg ligand-binding domain by computational solvent mapping. Biochemistry 44, 1193-1209.

Kumar S, Chen CS, Waxman DJ, Halpert JR. 2005. Directed evolution of mammalian cytochrome P450 2B1:   mutations outside of the active site enhance the metabolism of several substrates including the anticancer prodrugs cyclophosphamide and ifosfamide. J Biol Chem 280, 19569-19575.

Riddick DS, Lee C, Ramji S, Chinje EC, Cowen RL, Williams KJ, Patterson AV, Stratford IJ, Morrow CS, Townsend AJ, Jounaidi Y, Chen CS, Su T, Lu H, Schwartz PS, Waxman DJ.   2005. Cancer chemotherapy and drug metabolism (Review).   Drug Metab Dispos 33, 1083-1096.

Chen CS, Jounaidi Y, Waxman DJ. 2005. Enantioselective metabolism and cytotoxicity of R-ifosfamide and S-ifosfamide by tumor cell-expressed cytochromes P450. Drug Metab Dispos, 33, 1261-1267.

Waxman DJ, Chang TKH.   2005. Hormonal regulation of liver cytochrome P450 enzymes. In:   Ortiz de Montellano PR, ed. Cytochrome P450:   Structure, Mechanism and Biochemistry (Third Edition), Kluwer Academic/Plenum Publishers, NY, Chapter 9, 347-376.

Chang TKH, Waxman DJ.   2005. Pregnane X receptor-mediated transcription. Methods Enzymol 400 , 588-598.

2004

Schlezinger JJ, Howard GJ, Hurst CH, Emberley JK, Waxman DJ, Webster T, Sherr DH.   2004. Environmental and endogenous PPARg agonists induce bone marrow B cell growth arrest and apoptosis:   interactions between mono-(2-ethylhexyl) phthalate, 9- cis -retinoic acid, and 15-deoxy- D 12,14 -prostaglandin J2     J Immunol 173, 3165-3177.

Laz EV, Wiwi CA, Waxman DJ.   Sexual dimorphism of rat liver nuclear proteins:   regulatory role of growth hormone.   Molec Cell Proteomics 3, 1170-1180.

Ahluwalia A, Clodfelter KH, Waxman DJ. 2004. Sexual dimorphism of rat liver gene expression:  regulatory role of growth hormone revealed by DNA microarray analysis.  Molec Endocrinol 18, 747-760.

Su T, Waxman DJ. 2004. Impact of dimethyl sulphoxide on expression of nuclear receptors and drug-inducible cytochromes P450 in primary rat hepatocytes. Arch Biochem Biophys 424, 226-234.

Chen CS, Lin JT, Goss KA, He Y, Halpert JR, Waxman DJ.  2004. Activation of the anti-cancer prodrugs cyclophosphamide and ifosfamide.  Identification of P450 2B enzymes and site-specific mutants with improved enzyme kinetics.  Molec Pharmacol 65, 1278-1285.

Wiwi CA, Waxman DJ. 2004. Role of hepatocyte nuclear factors in growth hormone-regulated, sexually dimorphic expression of liver cytochromes P450.  Growth Factors 22, 79-88.

Shipley JM, Hurst CH, Tanaka SS, DeRoos FL, Butenhoff JL, Seacat AM, Waxman DJ. 2004. Trans-activation of PPARa and induction of PPARa target genes by perfluorooctane-based chemicals. Toxicol Sci 80, 151-160.

Wiwi CA, Gupte M, Waxman DJ.   2004. Sexually dimorphic P450 gene expression in liver-specific hepatocyte nuclear factor 4a-deficient mice. Molec Endocrinol 18, 1975-1987.

Shipley JM, Waxman DJ.   Simultaneous, bi-directional inhibitory cross-talk between PPAR and STAT5b.   Toxicol Appl Pharmacol 199, 275-284.

Hurst CH, Waxman DJ.   Environmental phthalate monoesters activate pregnane X receptor-mediated transcription.   Toxicol Appl Pharmacol 199, 266-274.

Jounaidi Y, Waxman DJ. 2004. Use of replication-conditional adenovirus as a helper system to enhance delivery of P450 prodrug-activation genes for cancer therapy. Cancer Res. Jan 1; 64(1):292-303.

Chiocca EA, Waxman DJ. 2004. Cytochrome p450-based gene therapies for cancer. Methods Mol Med. 90:203-22.

2003

Waxman DJ, Schwartz PS. 2003. Harnessing apoptosis for improved anticancer gene therapy. Cancer Res. Dec 15; 63(24):8563-72.

Waxman DJ, Celenza JL. 2003. Sexual dimorphism of hepatic gene expression: novel biological role of KRAB zinc finger repressors revealed. Genes Dev. Nov 1; 17(21):2607-13.

Baldwin A, Zeqi H, Youssef J, Waxman DJ. 2003. Identification of novel enzyme-prodrug combinations for use in cytochrome P450-based gene therapy for cancer.   Arch Biochem Biophys 409: 197-206.

Apletalina EV, Huan-Chen Li, Waxman DJ. 2003. Evaluation of thyroid hormone effects on liver P450 reductase translation.  Arch Biochem Biophys 409: 172-179.

Hurst CH, Waxman DJ. 2003. Activation of PPARa and PPAR g by environmental phthalate monoesters.  Toxicol Sciences 74: 297-308.

Schwartz PS, Chen CS, Waxman DJ. 2003. Sustained P450 expression and prodrug activation in bolus cyclophosphamide-treated cultured tumor cells. Impact of prodrug schedule on P450 gene-directed enzyme prodrug therapy.  Cancer Gene Therapy 10: 571-582.

Shipley JM, Waxman DJ. 2003. Down-regulation of STAT5b transcriptional activity by ligand-activated PPARalpha and PPARgamma.  Molec Pharmacol 64: 355-364.

2002

Schwartz PS, Chen CS, Waxman DJ. 2002. p 35.  Enhanced bystander cytotoxicity of P450 gene-directed enzyme prodrug therapy by expression of the antiapoptotic factor 62: 6928-6937.

Liu D, Waxman DJ. 2002. Post-transcriptional regulation of hepatic NADPH- P450 reductase by thyroid hormone: independent effect on poly(A) tail length and mRNA stability. Molec Pharmacol 61 1089-1096.

Zhou YC, Davey HW, McLachlan MJ, Waxman DJ. 2002. Elevated basal expression of liver peroxisomal b-oxidation enzymes and CYP4A microsomal fatty acid w-hydroxylase in STAT5b-/- mice. Cross-talk in vivo between PPAR and STAT signaling pathways. Toxidol Applied Pharmacol 182, 1-10.

Tzanakakis ES, Waxman DJ, Hansen LK, Remmel RP, Hu WS. 2002. Long-term enhancement of cytochrome P450 2B1/2 expression in rat hepatocyte spheroids through adenovirus-mediated gene transfer. Cell Biol Toxicol 18, 13-27.

Chen L, Waxman DJ. 2002. Cytochrome P450 gene-directed enzyme prodrug therapy (GDEPT) for cancer. Current Pharmaceutical Design 8 1405-1416.

2001

Schwartz PS, Waxman DJ. 2001. Cyclophosphamide induces caspsase 9-dependent apoptosis in 9L tumor cells. Molec Pharmacol 60 1268-1279.

Park SH, Yamashita H, Rui H, Waxman DJ. 2001. Serine phosphorylation of GH-activated STAT5a and STAT5b: impact on STAT5 transcriptional activity. Molec Endocrinol 15 2157-2171.

Tannenbaum GS, Choi HK, Gurd W, Waxman DJ. 2001. Temporal relationship between the sexually dimorphic spontaneous GH secretory profiles and hepatic stat5 activity. Endocrinology 142: 4599-4606.

Park SH, Waxman DJ. 2001. Inhibitory cross-talk between STAT5b and liver nuclear factor HNF3beta. Impact on the regulation of growth hormone pulse-stimulated, male-specific liver cytochrome P450 gene expression. J Biol Chem. 276 43031-43039.

Davey HW, Xie T, McLachlan MJ, Wilkins RJ, Waxman DJ, Grattan DR. 2001. STAT5b is required for GH-induced liver IGF-I gene expression. Endocrinology 142: 3836-41.

Huang Z, Waxman DJ. 2001. Modulation of cyclophosphamide-based cytochrome P450 gene therapy using liver P450 inhibitors. Cancer Gene Ther 8: 450-8.

Jounaidi Y, Waxman DJ. 2001. Frequent, moderate-dose cyclophosphamide administration improves the efficacy of cytochrome P-450/cytochrome P-450 reductase-based cancer gene therapy. Cancer Res 61: 4437-44.

Yu LJ, Matias J, Scudiero DA, Hite KM, Monks A, Sausville EA, Waxman DJ. 2001. P450 enzyme expression patterns in the NCI human tumor cell line panel. Drug Metab Dispos 29, 304-312.

Li HC, Liu D, Waxman DJ. 2001. Transcriptional induction of hepatic NADPH: cytochrome P450 oxidoreductase by thyroid hormone. Molec Pharmacol 59, 987-995.

Xie W, Radominska-Pandya A, Shi Y, Simon CM, Nelson MC, Ong ES, Waxman DJ, Evans RM. 2001. An essential role for SXR/PXR in detoxification of cholestatic bile acids. Proc Natl Acad Sci USA 98, 3375-3380.

2000

Dillon JS, Yaney GC, Zhou Y, Voilley N, Bowen S, Chipkin S, Bliss CR, Schultz V, Schuit FC, Prentki M, Waxman DJ, Corkey BE. 2000. Dehydroepiandrosterone sulfate and beta-cell function: enhanced glucose-induced insulin secretion and altered gene expression in rodent pancreatic beta-cells. Diabetes Dec; 49(12):2012-20.

Ram PA, Waxman DJ. 2000. Role of the cytokine-inducible SH2 protein CIS in desensitization of STAT5b signaling by continuous growth hormone. J Biol Chem Dec 15; 275(50):39487-96.

Choi HK, Waxman DJ. 2000. Related Articles Pulsatility of growth hormone (GH) signalling in liver cells: role of the JAK-STAT5b pathway in GH action. Growth Horm IGF Res Apr; 10 Suppl B:S1-8.

Choi HK, Waxman DJ. 2000. Related Articles Plasma growth hormone pulse activation of hepatic JAK-STAT5 signaling: developmental regulation and role in male-specific liver gene expression. Endocrinology Sep; 141(9):3245-55.

Delesque-Touchard N, Park SH, Waxman DJ .2000. Related Articles Synergistic action of hepatocyte nuclear factors 3 and 6 on CYP2C12 gene expression and suppression by growth hormone-activated STAT5b. PROPOSED MODEL FOR FEMALE-SPECIFIC EXPRESSION OF CYP2C12 IN ADULT RAT LIVER. J Biol Chem Nov 3;275(44):34173-82.

Huang Z, Raychowdhury MK, Waxman DJ. 2000. Impact of liver P450 reductase suppression on cyclophosphamide activation, pharmacokinetics and antitumoral activity in a cytochrome P450-based cancer gene therapy model. Cancer Gene Ther. 7: 1034-1042.

Huang Z, Roy P, Waxman DJ. 2000. Role of human liver microsomal CYP3A4 and CYP2B6 in catalyzing N-dechloroethylation of cyclophosphamide and ifosfamide. Biochem Pharmacol. 59: 961-972.

Jounaidi Y, Waxman DJ. 2000. Combination of the bioreductive drug tirapazamine with the chemotherapeutic prodrug cyclophosphamide for P450/P450-reductase-based cancer gene therapy. Cancer Res. 60: 3761-3769.

Waxman DJ. 2000. Growth hormone pulse-activated STAT5 signalling: a unique regulatory mechanism governing sexual dimorphism of liver gene expression. Novartis Found Symp. 227: 61-81. Review.

1999

Choi HK and Waxman DJ. 1999. Growth hormone, but not prolactin, maintains, low-level activation of STAT5a and STAT5b in female rat liver. Endocrinology 140:5126-35.

Davey HW, Wilkins RJ, and Waxman DJ. 1999. STAT5 Signaling in Sexually Dimorphic Gene Expression and Growth Patterns. Am J Hum Genet 65:959-965.

Davey HW, Park SH, Grattan DR, McLachlan MJ, and Waxman DJ. 1999. STAT5b-deficient Mice Are Growth Hormone Pulse-resistant Role of STAT5b in Sex-Specific Liver P450 Expression. J Biol Chem 274: 35331-36.

Gebert CA, Park SH, and Waxman DJ. 1999. Down-regulation of liver JAK2-STAT5b signaling by the female plasma pattern of continuous growth hormone stimulation.  Mol Endocrinol 13: 213-227.

Gebert CA, Park SH, and Waxman, DJ. 1999.  Termination of growth hormone pulse-induced STAT5b signaling. Mol Endocrinol 13, 38-56.

Huang Z and Waxman DJ. 1999. High-performance liquid chromatographic-fluorescent method to determine chloroacetaldehyde, a neurotoxic metabolite of the anticancer drug ifosfamide, in plasma and in liver microsomal incubations. Anal Biochem 273:117-25.

Maloney EK and Waxman DJ. 1999. trans-Activation of PPARa and PPARg by Structurally Diverse Environmental Chemicals. Toxicol Appl Pharmacol 161:209-218.

Park SH, Liu X, Hennighausen L, Davey HW, and Waxman DJ. 1999. Distinctive roles of STAT5a and STAT5b in sexual dimorphism of hepatic P450 gene expression. Impact of Stat5a gene disruption. J Biol Chem  274: 7421-7430.

Ram PA and Waxman DJ. 1999. SOCS/CIS Protein Inhibition of Growth Hormone-stimulated STAT5 Signaling by Multiple Mechanisms. J Biol Chem 274: 35553-61.

Roy P, Tretyakov O, Wright J, and Waxman DJ. 1999. Stereoselective metabolism of ifosfamide by human P-450s 3A4 and 2B6. Favorable metabolic properties of R-enantiomer. Drug Metab Dispos 27:1309-18.

Roy P, Yu LJ, Crespi CL, and Waxman DJ. 1999. Development of a substrate-activity based approach To identify the major human liver P-450 catalysts of cyclophosphamide and ifosfamide activation based on cDNA-expressed activities and liver microsomal P-450 profiles. Drug Metab Dispos 27: 655-66.

Waxman DJ. 1999. P450 gene induction by structurally diverse xenochemicals: central role of nuclear receptors CAR, PXR, and PPAR. Arch Biochem Biophys 369:11-23. Review.

Waxman DJ, Chen L, Hecht JE, and Jounaidi Y. 1999. Cytochrome P450-based cancer gene therapy: recent advances and future prospects. Drug Metab Rev 31: 503-22.

Yu LJ, Drewes P, Gustafsson K, Brain EG, Hecht JE, and Waxman DJ. 1999. In vivo modulation of alternative pathways of P-450-catalyzed cyclophosphamide metabolism: impact on pharmacokinetics and antitumor activity. J Pharmacol Exp Ther 288: 928-937.

Zhou YC and Waxman, DJ. 1999. STAT5b down-regulates peroxisome proliferator-activated receptor alpha transcription by inhibition of ligand-independent activation function region-1 trans-activation domain. J Biol Chem 274:29874-82.

Zhou YC and Waxman, DJ. 1999. Cross-talk between janus kinase-signal transducer and activator of transcription (JAK-STAT) and peroxisome proliferator-activated receptor-alpha (PPARalpha) signaling pathways. Growth hormone inhibition of PPAR-alpha transcriptional activity mediated by STAT5b. J Biol Chem 274:2672-2681.

1998

Jounaidi, Y, Hecht, JE, Waxman, DJ. 1998. Retroviral transfer of human cytochrome P450 genes for oxazaphosphorine-based cancer gene therapy. Cancer Res. 58, 4391-4401.

Zhou,YC, Waxman, DJ. 1998. Activation of peroxisome proliferator-activated receptors by chlorinated hydrocarbons and endogenous steroids. Environ Health Perspect. 106 Suppl 4, 983-988.

Brain EG, Yu LJ, Gustafsson K, Drewes P, Waxman DJ. 1998. Modulation of P450-dependent ifosfamide pharmacokinetics: a better understanding of drug activation in vivo. Br J Cancer. 77, 1768-1776.

1997

Chen L, Yu LJ, Waxman DJ. 1997. Potentiation of cytochrome P450/cyclophosphamide-based cancer gene therapy by coexpression of the P450 reductase gene. Cancer Res 57, 4830-4837

Gebert CA, Park SH, Waxman DJ. 1997. Regulation of signal transducer and activator of transcription (STAT) 5b activation by the temporal pattern of growth hormone stimulation. Molec Endocrinol 11, 400-414.

Ram PA, Waxman DJ. 1997. Interaction of growth hormone-activated STATs with SH2-containing phosphotyrosine phosphatase SHP-1 and nuclear JAK2 tyrosine kinase J Biol Chem 272, 17694-17702

Chang TKH, Yu L, Maurel P, Waxman DJ. 1997. Enhanced cyclophosphamide and ifosfamide activation in primary human hepatocyte cultures: Response to cytochrome P-450 inducers and autoinduction by oxazaphosphorines. Cancer Res 57, 1946-1954.

Udy GB, Towers RP, Snell RG, Wilkins RJ, Park SH, Ram PA, Waxman DJ, Davey HW. 1997. Requirement of STAT5b for sexual dimorphism of body growth rates and liver gene expression. Proc Natl Acad Sci USA 94, 7239-7244.

1996

Chen L, Waxman DJ, Chen D, Kufe D. 1996. Sensitization of human breast cancer cells to cyclophosphamide and ifosfamide by transfer of a liver cytochrome P450 gene. Canc Res 56, 1331-1340.

Peters JM, Zhou YC, Ram PA, Lee SST, Gonzalez FJ, Waxman DJ. 1996. Peroxisome proliferator-activated receptor a required for gene induction by dehydroepiandrosterone 3-beta-sulfate. Molec Pharmacol 50, 67-74.

Ram P.A., S-H Park, H.K. Choi, and D.J. Waxman. 1996. Growth hormone activation of Stat 1, Stat 3 and Stat 5 in rat liver. Differential kinetics of hormone desensitization and GH-stimulation of both tyrosine phosphorylation and serine/threonine phosphorylation. J Biol Chem 271, 5929-5940.

1995

Chen, L., and D.J.Waxman. 1995.Intratumoral activation and enhanced chemotherapeutic effect of oxazaphosphorines following cytochrome P450 gene transfer: development of a combined chemotherapy/cancer gene therapy strategy. Canc Res 55, 581-589.

Waxman, D.J., P.A. Ram, S-H Park, and H.K. Choi. 1995. Intermittent plasma growth hormone triggers tyrosine phosphorylation and nuclear translocation of a liver-expressed, Stat 5-related DNA-binding protein. Proposed role as an intracellular regulator of male-specific liver gene transcription. J Biol Chem 270, 13262-13270.

Questions and comments are always welcome.
Copyright © 1996, The Trustees of Boston University
This document was last modified on January 23, 2008.