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Tucker GT, Houston JB, Huang SM. Optimizing drug development: strategies to assess drug metabolism/transporter interaction potential--towards a consensus. Br J Clin Pharmacol 2001; 52:107-17. [PMID: 11453898 PMCID: PMC2014497 DOI: 10.1046/j.0306-5251.2001.temp.1441.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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52
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Tucker GT, Houston JB, Huang SM. EUFEPS conference report. Optimising drug development: strategies to assess drug metabolism/transporter interaction potential - towards a consensus. European Federation of Pharmaceutical Sciences. Eur J Pharm Sci 2001; 13:417-28. [PMID: 11480400 DOI: 10.1016/s0928-0987(01)00148-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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53
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Chiang BC, Wey MY, Huang SM. Heat treatment of incinerator retired sorbents containing heavy metals. THE SCIENCE OF THE TOTAL ENVIRONMENT 2001; 273:83-92. [PMID: 11419605 DOI: 10.1016/s0048-9697(00)00845-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Previous studies have indicated that an effective control technique for heavy metal emissions from incinerators is to use solid sorbents to capture metals by physical deposition and chemical adsorption. However, the adsorbed heavy metals on the retired sorbents could possibly cause secondary pollution if they are inadequately treated. The main objective of this study is to increase the stability of four heavy metals (Cu, Pb, Cr and Cd) on retired sorbents by heat treatment. The stability was based on the toxicity characteristic leaching procedure (TCLP) tests. The parameters evaluated included: (1) different temperatures (900, 1100 and 1300 degrees C); and (2) various heating times (20, 40 and 60 min). The results indicated that most of the leaching rates decreased with increasing temperature for the four toxic heavy metals. The heat treatment time did not regularly influence the stability of heavy metals, and affected it slightly when the temperature was controlled at 1300 degrees C.
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Huang SM, Schönthal AH, Stallcup MR. Enhancement of p53-dependent gene activation by the transcriptional coactivator Zac1. Oncogene 2001; 20:2134-43. [PMID: 11360197 DOI: 10.1038/sj.onc.1204298] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2000] [Revised: 01/19/2001] [Accepted: 01/25/2001] [Indexed: 12/25/2022]
Abstract
A recently discovered potential tumor suppressor protein, Zac1, was previously shown to promote cell cycle arrest and apoptosis, and to act as a positive or negative transcriptional cofactor for nuclear receptors. Since these activities are common to Zac1 and p53, we tested for a functional interaction between these two proteins by investigating possible effects of Zac1 on the transcriptional activator function of p53. Zac1 specifically enhanced the activity of p53-responsive promoters in cells expressing wild type p53. The same promoters were not activated by Zac1 in cells lacking functional p53, but the Zac1 effect was restored by co-expression of p53. Zac1 bound to p53 and enhanced the activity of p53 or its N-terminal transcriptional activation domain fused to the DNA binding domain of Gal4. These results indicate that Zac1 served as a transcriptional coactivator for p53. The enhancement of p53 activity by Zac1 was much more dramatic in HeLa cells than in other cell lines tested. HeLa cells express human papillomavirus type 18 E6 protein which inactivates and causes the degradation of p53. Physical and functional interactions observed between Zac1 and E6 protein indicated that the dramatic activity of Zac1 in HeLa cells was due not only to Zac1's coactivator effect on p53, but also to the ability of Zac1 to reverse E6 inhibition of p53.
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Huang RF, Huang SM, Lin BS, Wei JS, Liu TZ. Homocysteine thiolactone induces apoptotic DNA damage mediated by increased intracellular hydrogen peroxide and caspase 3 activation in HL-60 cells. Life Sci 2001; 68:2799-811. [PMID: 11432446 DOI: 10.1016/s0024-3205(01)01066-9] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The cytotoxicity of homocysteine derivatives on chromosomal damage in somatic cells is not well established. The present study used reactive homocysteine derivative of homocysteine thiolactone (Hcy) to investigate its causal effect on apoptotic DNA injury in human promyeloid HL-60 cells. Our results demonstrated that Hcy induced cell death and features of apoptosis including increased phosphotidylserine exposure on the membrane surface, increased apoptotic cells with hypoploid DNA contents, and internucleosomal DNA fragmentation, all of which occurred in a time- and concentration-dependent manner. Hcy treatment also significantly increased intracellular reactive oxygen species H2O2, which coincided with the elimination of caspase 3 proenzyme levels and increased caspase 3 activity at the time of the appearance of apoptotic DNA fragmentation. Preincubation of Hcy-treated HL-60 cells with catalase completely scavenged intracellular H2O2, thus inhibiting caspase 3 activity and protecting cells from apoptotic DNA damage. In contrast, superoxide dismutase failed to inhibit Hcy-induced DNA damage. Taken together, these results demonstrate that Hcy exerted its genotoxic effects on HL-60 cells through an apoptotic pathway, which is mediated by the activation of caspase 3 activity induced by an increase in intracellular hydrogen peroxide.
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56
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Huang SC, Lee MC, Wei CK, Huang SM. Endothelin receptors in human and guinea-pig gallbladder muscle. REGULATORY PEPTIDES 2001; 98:145-53. [PMID: 11231044 DOI: 10.1016/s0167-0115(00)00238-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We measured contraction of muscle strips caused by endothelin (ET) isopeptides and binding of (125)I-ET-1 to muscle cell membranes prepared from human and guinea-pig gallbladders. Visualization of (125)I-ET-1 binding sites in tissue was performed by autoradiography. Results in human were similar to those in guinea-pig. ET-1 caused tetrodotoxin and atropine-insensitive contraction. The relative potencies for ET isopeptides to cause contraction were ET-1=ET-2>ET-3. ET-1 caused contraction was only slightly inhibited by BQ-123 (potent ET(A) receptor antagonist) and not by BQ-788 (potent ET(B) receptor antagonist). It was inhibited by the combination of both. Autoradiography localized (125)I-ET-1 binding to the smooth muscle layer. Binding of (125)I-ET-1 to muscle cell membranes was saturable and specific. Analysis of dose-inhibition curves demonstrated the presence of two classes of receptors. One class (ET(A) receptor) had a high affinity for ET-1 and ET-2 but a low affinity for ET-3, and the other (ET(B) receptor) a high affinity for ET-1, ET-2 and ET-3. These results demonstrate that similar to guinea-pig, human gallbladder possesses both ET(A) and ET(B) receptors cooperating to mediate muscle contraction.
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57
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Huang SM, Kuo MS, Jin YT, Liu HT, Wang WP. Prophylactic total thyroidectomy in an 8-year-old girl with multiple endocrine neoplasia type 2A. J Formos Med Assoc 2001; 100:274-6. [PMID: 11393128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
We report a genetic carrier of multiple endocrine neoplasia type 2A (MEN 2A) who underwent prophylactic total thyroidectomy. The asymptomatic carrier of MEN 2A, an 8-year-old Taiwanese girl, was admitted for early thyroidectomy. Preoperative basal plasma concentrations of calcitonin and intact parathyroid hormone, and urine vanillylmandelic acid excretion, were normal. Ultrasonography of the thyroid was also normal. Pathology did not reveal any gross lesion but C-cell hyperplasia of the thyroid gland was found microscopically. Prophylactic total thyroidectomy is encouraged and is justified during the first decade of life for MEN 2A carriers.
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Huang SM, Lee JC, Wu TJ, Chow NH. Clinical relevance of vascular endothelial growth factor for thyroid neoplasms. World J Surg 2001; 25:302-6. [PMID: 11343180 DOI: 10.1007/s002680020085] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Angiogenesis is of vital importance during the development and progression of solid tumors. Vascular endothelial growth factor (VEGF) is a major regulator of angiogenesis and could be produced by some cancer cells. To investigate the clinical relevance of VEGF in the tumorigenesis of human thyroid, an immunohistochemical study was performed on archival materials of follicular adenomas (n = 13), Hürthle cell adenomas (n = 6), papillary carcinomas (n = 76), follicular carcinomas (n = 12), Hürthle cell carcinomas (n = 2), and anaplastic carcinomas (n = 8). Patterns of VEGF expression were analyzed in relation to histologic subtypes of thyroid tumors and were correlated to biologic indicators of papillary carcinoma. All papillary carcinomas and Hürthle cell neoplasms revealed a strong, diffuse staining reaction, whereas anaplastic carcinoma usually exhibited weak and infrequent immunoreactivity. VEGF levels were usually higher in follicular adenomas than in follicular carcinomas. With regard to prognostic value, VEGF expression did not correlate with tumor size, extent of invasion, or scores on the AGES system (i.e., patient age, tumor size, histologic grade, tumor extent, distant metastasis) or the MACIS system (i.e., metastasis, age, completeness of resection, invasion, tumor size) for papillary carcinomas (p > 0.05, respectively). The results of the current study indicate that VEGF may play a role in the development of human thyroid cancer. Determination of the angiogenic phenotype may have limited prognostic value for patients with papillary carcinoma.
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Abstract
The preoperative diagnosis of a cecal perforation associated with Salmonella infection as a cause of abdominal-wall necrotizing fasciitis (AWNF) is clinically difficult. Computed tomography of the abdomen is helpful, and can detect the combined presence of a pneumoscrotum and pneumoperitoneum. Its presence indicates a patent processus vaginalis, which acts as the primary route for the spread of the intra-abdominal infectious process into the abdominal wall. An exploratory laparotomy should be done to confirm the presence of intra-abdominal pathology in order to avoid delayed treatment.
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Harari PM, Huang SM. Head and neck cancer as a clinical model for molecular targeting of therapy: combining EGFR blockade with radiation. Int J Radiat Oncol Biol Phys 2001; 49:427-33. [PMID: 11173137 DOI: 10.1016/s0360-3016(00)01488-7] [Citation(s) in RCA: 159] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE/OBJECTIVE The primary purpose of this presentation is to develop the concept that molecular blockade of specific growth factor receptors and signal transduction pathways in combination with radiation will prove a valuable cancer therapeutic strategy. More specifically, the rationale for molecular blockade of the epidermal growth factor receptor (EGFR) system in combination with ionizing radiation for epithelial tumors, such as squamous cell carcinomas (SCCs) of the head and neck (H&N), is described. METHODS AND MATERIALS Preclinical experimentation with in vitro and in vivo model systems regarding the capacity of EGFR blockade, using the monoclonal antibody C225, to modulate SCC tumor growth behavior and response to radiation is presented. The rationale for new clinical trials that are currently exploring this concept are presented. RESULTS Blockade of the EGFR system in SCC cell lines with C225 induces G1 cell cycle arrest with an associated decrease in the S-phase fraction. Inhibition of tumor cell proliferation is readily measured following C225 exposure and the corresponding alterations in expression of key regulators of the G1-S cell cycle phase transition are identified. Exposure of SCCs to C225 in culture enhances radiosensitivity following single-dose radiation exposure. Profound augmentation of the in vivo radiation response of SCC tumor xenografts in athymic mice is similarly demonstrated following systemic administration of C225. Preliminary studies are presented regarding potential underlying mechanisms of action for this enhanced tumor response to the combination of C225 and radiation including: (a) proliferative growth inhibition, (b) enhancement of radiation-induced apoptosis, (c) inhibition of damage repair, and (d) downregulation of tumor angiogenic response. Preliminary observations from the Phase III multicenter clinical trial examining C225 plus radiation therapy for advanced H&N cancer patients are provided. CONCLUSION Molecular inhibition of the EGFR signal transduction system in combination with radiation represents a promising investigational area in cancer therapeutics. Epithelial tumors that are rich in their expression of EGFR (e.g., SCC of the H&N) hold special promise for receptor blockade approaches. More broadly, the ultimate therapeutic effect of selected molecular agents which block specific growth factor receptors and signaling pathways may be enhanced when delivered in combination with radiation.
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61
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Huang SM, Li J, Harari PM. Monoclonal antibody blockade of the epidermal growth factor receptor in cancer therapy. CANCER CHEMOTHERAPY AND BIOLOGICAL RESPONSE MODIFIERS 2001; 19:339-52. [PMID: 11686022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
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62
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Chen D, Huang SM, Stallcup MR. Synergistic, p160 coactivator-dependent enhancement of estrogen receptor function by CARM1 and p300. J Biol Chem 2000; 275:40810-6. [PMID: 11010967 DOI: 10.1074/jbc.m005459200] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Members of the p160 coactivator family (steroid receptor coactivator-1 (SRC-1), glucocorticoid receptor interacting protein 1 (GRIP1), and activator of thyroid and retinoic acid receptors (ACTR)) mediate transcriptional activation by nuclear receptors. After being recruited to the promoter by nuclear receptors, the p160 coactivator transmits the activating signal via two C-terminal activation domains, AD1 and AD2. AD1 is a binding site for the related coactivators cAMP-response element binding protein binding protein (CBP) and p300, whereas AD2 binds to another coactivator, coactivator-associated arginine methyltransferase 1 (CARM1), a protein-arginine methyltransferase. The current study explored the cooperative functional and mechanistic relationships among GRIP1, CARM1, and p300 in transient transfection assays, where they enhanced the ability of the estrogen receptor (ER) to activate transcription of a reporter gene. The coactivator functions of p300 and CARM1 depended on the co-expression of GRIP1. Simultaneous co-expression of all three coactivators caused a synergistic enhancement of ER function. Deletion of the AD1 domain of GRIP1 abolished the ability of p300 to potentiate ER activity but had no effect on CARM1-mediated stimulation. In contrast, when the AD2 domain of GRIP1 was deleted, p300 still stimulated ER function through the mutant GRIP1, but CARM1 failed to do so. Thus, both binding of p300 to AD1 and binding of CARM1 to AD2 are required for their respective coactivator functions and for their synergy. Furthermore, CARM1 and p300 function independently through different activating domains of GRIP1, and their synergy suggests that they enhance transcription by different, complementary mechanisms.
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63
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Huang SM, Fielden J, Green RG, Beck MS. A new capacitance transducer for industrial applications. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3735/21/3/002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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64
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Huang SM, Stott AL, Green RG, Beck MS. Electronic transducers for industrial measurement of low value capacitances. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3735/21/3/001] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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65
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Huang SM, Green RG, Plaskowski AB, Beck MS. Conductivity effects on capacitance measurements of two-component fluids using the charge transfer method. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3735/21/6/003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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66
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Xie CG, Stott AL, Huang SM, Plaskowski A, Beck MS. Mass-flow measurement of solids using electrodynamic and capacitance transducers. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3735/22/9/007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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67
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Huang SM, Plaskowski AB, Xie CG, Beck MS. Tomographic imaging of two-component flow using capacitance sensors. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3735/22/3/009] [Citation(s) in RCA: 184] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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68
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Cheng JS, Lai KH, Lo GH, Ng WW, Tam TN, Huang SM. In vitro dissolution of cholesterol and brown pigmented gallstones: a comparison of MTBE, DMSO and BA-EDTA. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2000; 63:667-72. [PMID: 11037641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND Gallstones are a common problem in Taiwan and surgical removal remains the essential treatment. Successful dissolution of the stones with chemical solutions and then removal by endoscopic or percutaneous methods have previously been reported. We designed this study to find the ideal agent for dissolving gallstones. METHODS Twelve chemical solutions with dimethylsulfoxide (DMSO), methyl tert-butyl ether (MTBE) and ethylenediamine tetra-acetic acid (EDTA) in different mixtures were tested to investigate their ability to dissolve gallstones in vitro. The dissolution of stones was performed at 37 degrees C and each procedure was repeated five to seven times. RESULTS The solvent containing DMSO/MTBE (1/1) had a higher dissolving capacity for cholesterol stones, with solubility reaching 96.8% after 6 hours. The solution containing DMSO/MTBE (7/3) had the maximal solubility for calcium bilirubinate stones, with solubility reaching 22.9% after 6 hours. Also, we found that the intact stones of calcium bilirubinate became fragmented after treatment with the DMSO/MTBE solution without stirring. CONCLUSIONS The DMSO, MTBE and EDTA agents that we used effectively dissolved gallstones, especially cholesterol stones, in vitro. Further in vivo studies are necessary to confirm the efficacy and safety of these solvents before clinical application.
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69
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Dong L, Guo M, Huang SM, Jia SQ, Wang H. Transcripts of immunoglobulin germline mu: an amplified myeloid and B-lymphoid common gene program in various leukemias. Acta Haematol 2000; 101:119-23. [PMID: 10352329 DOI: 10.1159/000040936] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To investigate the clinical implications of germline C mu transcription, the splice region between the 3' end of the enhancer and the first exon of immunoglobulin germline mu; was analyzed by RT-PCR in 63 samples from 59 patients with leukemia. Immunophenotypes of 33 samples from patients with acute leukemia were analyzed using a panel of these monoclonal antibodies: anti-immature/stem cell (HLA-DR, CD34); anti-mature myeloid (CD33, CD15); anti-T lymphoid (CD2, CD3, CD5, CD7, CD8), and anti-B lymphoid (CD10, CD19, CD20). Of the 63 samples, 33 (52%) contained germline C mu transcripts: 2/2 patients with chronic lymphocytic leukemia; 17/26 (65.4%) patients with acute myeloblastic leukemia; all 4 patients with chronic myelogenous leukemia in blast crisis and 1 in accelerated phase; 9/12 patients with acute lymphocytic leukemia. A clear correlation between germline transcripts and HLA-DR expression was observed among germline-positive cases (p < 0. 01). C mu expression and response to therapy clearly indicated that germline-mu-positive leukemia patients responded poorly to chemotherapy and had a worse clinical prognosis compared with C mu-negative patients (p < 0.01). After two courses of chemotherapy, 7/9 C mu-negative patients achieved complete remission compared to only 7/29 C mu-positive patients (p < 0.01). We conclude that the gene-regulating immunoglobulin germline C mu may be amplified in myeloid and B-lymphoid cells during leukemogenesis. Such genetic changes may be correlated with cellular terminal differentiation injury, resistance to chemotherapy and uncontrolled malignant cell proliferation.
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MESH Headings
- Adolescent
- Adult
- Aged
- Base Sequence
- Child
- Child, Preschool
- Female
- Gene Amplification/genetics
- Gene Amplification/immunology
- Gene Expression Regulation, Leukemic/genetics
- Gene Expression Regulation, Leukemic/immunology
- Genes, Immunoglobulin/genetics
- Genes, Immunoglobulin/immunology
- Humans
- Immunoglobulin Variable Region/genetics
- Immunoglobulin Variable Region/immunology
- Immunophenotyping
- Leukemia, B-Cell/genetics
- Leukemia, B-Cell/immunology
- Leukemia, Myeloid/genetics
- Leukemia, Myeloid/immunology
- Male
- Middle Aged
- Molecular Sequence Data
- Oligonucleotide Probes
- Polymerase Chain Reaction/methods
- RNA, Neoplasm/isolation & purification
- Sensitivity and Specificity
- Transcription, Genetic
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Cherng JM, Lin CM, Lin CL, Huang SM, Chang HL, Lee CC, Chiang LC, Chang PY. Effects of VEGF121 and/or VEGF165 gene transfection on collateral circulation development. J Formos Med Assoc 2000; 99:603-11. [PMID: 10969502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
BACKGROUND AND PURPOSE Angiogenesis is regulated by various factors, including vascular endothelial growth factor (VEGF). Five isoforms of VEGF have been discovered: VEGF121, VEGF145, VEGF165, VEGF189, and VEGF206. The teleologic basis for the various VEGF isoforms remains unclear, but different VEGF isoforms may mediate distinct endothelial cell functions such as angiogenesis, vascular permeability, and differentiation. We sought to determine the effects of various VEGF isoforms on angiogenesis under ischemic conditions in rabbits. METHODS The effects of VEGF121 and/or VEGF165 gene transfection on collateral circulation development in ischemic rabbit hindlimb muscles were investigated by using naked plasmids encoding VEGF121 or VEGF165 (pVEGF121 or pVEGF165), either individually or in combination. pCMV beta was used as the control plasmid. The femoral artery on one side of New Zealand White rabbits was ligated. Ten days later, the ischemic muscles received direct intramuscular injection of pVEGF121 (500 micrograms), pVEGF165 (500 micrograms), or pVEGF121 (250 micrograms) + pVEGF165 (250 micrograms) in experimental groups, while pCMV beta (500 micrograms) was used in the control group. Therapeutic effects were evaluated 30 days later by anatomic and physiologic analysis. RESULTS Internal iliac angiography showed strong development of collateral circulation in all of the pVEGF-treated groups. In contrast, collateral arteries developed weakly in the control group. Combination treatment with both pVEGF121 and pVEGF165 did not result in additional improvement compared with pVEGF121 or pVEGF165 treatment alone (angiographic scores: pVEGF121 = 0.85 +/- 0.10; pVEGF165 = 0.81 +/- 0.11; pVEGF121 + pVEGF165 = 0.83 +/- 0.09; control = 0.53 +/- 0.09; p < 0.01). A favorable response in the development of circulation at the capillary level with pVEGF121 and/or pVEGF165 versus pCMV beta was also found. Blood pressure measurement and regional blood flow measurement using colored microspheres revealed similar results. CONCLUSIONS Our results show that direct intramuscular injection of naked DNA encoding VEGF121 or VEGF165, individually or in combination, is an effective method for gene transfer in an animal model of ischemic limbs and results in augmented collateral vascular development and tissue perfusion.
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Huang SM, Harari PM. Modulation of radiation response after epidermal growth factor receptor blockade in squamous cell carcinomas: inhibition of damage repair, cell cycle kinetics, and tumor angiogenesis. Clin Cancer Res 2000; 6:2166-74. [PMID: 10873065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
We have recently demonstrated that molecular blockade of the epidermal growth factor receptor with the anti-epidermal growth factor receptor (EGFR) monoclonal antibody C225 enhances the in vitro radiosensitivity of human squamous cell carcinomas (SCCs) derived from the head and neck. In the present study, we further investigated the capacity of C225 to modulate the in vitro and in vivo radiation response of human SCC tumor cells and xenografts, and we examined several potential mechanisms that may contribute to the enhanced radiation response induced by C225. Tumor xenograft studies demonstrated complete regression of both newly established (20 mm3) and well-established (100 mm3) SCC tumors over a 55-100 day follow-up period in athymic mice treated with the combination of C225 (i.p. injection) and radiation. Cell cycle analysis via flow cytometry confirmed that combined treatment with C225 and radiation induced an accumulation of cells in the more radiosensitive cell cycle phases (G1, G2-M) with concurrent reduction in the proportion of cells in the more radioresistant S phase. Results from sublethal damage repair and potentially lethal damage repair analyses in cultured SCC cells demonstrated a strong inhibitory effect of C225 on postradiation damage repair. Further, exposure of SCC cells to C225 induced a redistribution of DNA-dependent protein kinase from the nucleus to the cytosol, suggesting one potential mechanism whereby C225 may influence the cellular response to radiation. Immunohistochemical analysis of SCC tumor xenografts after systemic administration of C225 demonstrated inhibition of the in vivo expression of tumor angiogenesis markers, including vascular endothelial growth factor and Factor VIII. Taken together, the collective data suggest that the profound in vivo antitumor activity identified in the xenograft setting when C225 is combined with radiation derives from more than simply the antiproliferative and cell cycle effects of EGFR system inhibition. In addition to antiproliferative growth inhibition, EGFR blockade with C225 appears to influence the capacity of human SCCs to effect DNA repair after exposure to radiation, and to express classic markers of tumor angiogenesis.
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MESH Headings
- Animals
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Humanized
- Antineoplastic Agents/therapeutic use
- Carcinoma, Squamous Cell/drug therapy
- Carcinoma, Squamous Cell/pathology
- Carcinoma, Squamous Cell/radiotherapy
- Cell Cycle/drug effects
- Cell Cycle/radiation effects
- Cell Nucleus/metabolism
- Cetuximab
- Cytosol/metabolism
- DNA Repair/drug effects
- DNA Repair/radiation effects
- DNA-Activated Protein Kinase
- DNA-Binding Proteins
- Dose-Response Relationship, Radiation
- Endothelial Growth Factors/biosynthesis
- ErbB Receptors/antagonists & inhibitors
- Factor VIII/biosynthesis
- Female
- Flow Cytometry
- Head and Neck Neoplasms/drug therapy
- Head and Neck Neoplasms/pathology
- Head and Neck Neoplasms/radiotherapy
- Humans
- Immunoblotting
- Immunohistochemistry
- Kinetics
- Lymphokines/biosynthesis
- Mice
- Mice, Nude
- Neoplasm Transplantation
- Neovascularization, Pathologic
- Nuclear Proteins
- Proliferating Cell Nuclear Antigen/biosynthesis
- Protein Serine-Threonine Kinases/biosynthesis
- Radiation Tolerance
- Recombinant Fusion Proteins/therapeutic use
- Subcellular Fractions/metabolism
- Time Factors
- Tumor Cells, Cultured
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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72
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Lee JC, Chow NH, Wang ST, Huang SM. Prognostic value of vascular endothelial growth factor expression in colorectal cancer patients. Eur J Cancer 2000; 36:748-53. [PMID: 10762747 DOI: 10.1016/s0959-8049(00)00003-4] [Citation(s) in RCA: 221] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Solid tumours require neovascularisation for growth and metastasis. Vascular endothelial growth factor (VEGF) has been shown to be an important regulator of tumour angiogenesis. To examine the relevance of VEGF in the neoplastic transformation of human colon, we analysed protein expression in a total 30 polyps and 145 colorectal carcinomas by immunohistochemistry. All adenoma specimens, regardless of histological differentiation, and normal colonic mucosa did not express VEGF. Amongst 90 patients with non-metastatic colorectal cancer, VEGF expression was observed in 43 (48%) cases, whilst 29 of the 55 patients (53%) with metastases expressed the angiogenic factor. Both the proportion and intensity of VEGF expression were positively associated with the progression of colon carcinogenesis. Tumours with the highest VEGF expression tended to correlate with patients' survival, although VEGF expression did not emerge as an independent risk factor in a multivariate analysis. After exclusion of the patients with distant metastases, both univariate and multivariate analysis did not indicate any prognostic value for the tissues with the highest VEGF expression. Our results suggest that VEGF may play a role in the progression of colon cancer, although evaluation of this angiogenic phenotype did not provide additional prognostic information compared with that obtained from Dukes' staging of the tumours.
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Sahi J, Hamilton G, Sinz M, Barros S, Huang SM, Lesko LJ, LeCluyse EL. Effect of troglitazone on cytochrome P450 enzymes in primary cultures of human and rat hepatocytes. Xenobiotica 2000; 30:273-84. [PMID: 10752642 DOI: 10.1080/004982500237668] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
1. Troglitazone was the first thiazolidinedione approved for clinical use in the treatment of non-insulin-dependent diabetes mellitus. During clinical investigations of drug-drug interactions with therapeutics (terfenadine and cyclosporine) known to be metabolized by CYP3A4, pharmacokinetic interactions were noted upon troglitazone multiple-dose treatments. The nature of the interactions suggested induction of CYP3A enzymes. 2. Primary cultures of human hepatocytes were used to investigate the induction potential of troglitazone with respect to CYP3A4, CYP2B6 and CYP1A1/2. In human hepatocytes, troglitazone induced both immunoreactive CYP3A4 protein and testosterone 6beta-hydroxylase activity in a dose-dependent fashion (EC50 = 5-10 microM), accompanied by an increase in CYP3A4 mRNA. The capacity of troglitazone to induce CYP3A4 was between that of rifampin (EC50 = 0.8 microM) and dexamethasone (40-50 microM). Troglitazone increased CYP2B6 immunoreactive protein but did not significantly effect CYP1A1/2 activity, immunoreactive protein or mRNA. 3. Troglitazone produced significant increases in CYP3A message, protein and activity in primary rat hepatocytes, a slight increase in CYP2B1/2 activity and no change in CYP1A1/2 message or activity. 4. These results provide evidence that troglitazone can induce CYP3A and CYP2B enzymes while apparently not altering CYP1A. This provides a rationale for the clinically observed interactions of troglitazone with selected CYP3A4 substrates.
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Huang SM, Stallcup MR. Mouse Zac1, a transcriptional coactivator and repressor for nuclear receptors. Mol Cell Biol 2000; 20:1855-67. [PMID: 10669760 PMCID: PMC85366 DOI: 10.1128/mcb.20.5.1855-1867.2000] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/1999] [Accepted: 11/29/1999] [Indexed: 11/20/2022] Open
Abstract
Transcriptional activation by nuclear hormone receptors is mediated by the 160-kDa family of nuclear receptor coactivators. These coactivators associate with DNA-bound nuclear receptors and transmit activating signals to the transcription machinery through two activation domains. In screening for mammalian proteins that bind the C-terminal activation domain of the nuclear receptor coactivator GRIP1, we identified a new variant of mouse Zac1 which we call mZac1b. Zac1 was previously discovered as a putative transcriptional activator involved in regulation of apoptosis and the cell cycle. In yeast two-hybrid assays and in vitro, mZac1b bound to GRIP1, to CREB-binding protein (CBP) and p300 (which are coactivators for nuclear receptors and other transcriptional activators), and to nuclear receptors themselves in a hormone-independent manner. In transient-transfection assays mZac1b exhibited a transcriptional activation activity when fused with the Gal4 DNA binding domain, and it enhanced transcriptional activation by the Gal4 DNA binding domain fused to GRIP1 or CBP fragments. More importantly, mZac1b was a powerful coactivator for the hormone-dependent activity of nuclear receptors, including androgen, estrogen, glucocorticoid, and thyroid hormone receptors. However, with some reporter genes and in some cell lines mZac1b acted as a repressor rather than a coactivator of nuclear receptor activity. Thus, mZac1b can interact with nuclear receptors and their coactivators and play both positive and negative roles in regulating nuclear receptor function.
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Huang SM, Harari PM. Epidermal growth factor receptor inhibition in cancer therapy: biology, rationale and preliminary clinical results. Invest New Drugs 2000; 17:259-69. [PMID: 10665478 DOI: 10.1023/a:1006384521198] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The epidermal growth factor receptor (EGFR), a growth factor receptor involved in the regulation of cellular differentiation and proliferation, is highly expressed by many tumor cells. In light of a relationship between overexpression of EGFR and clinically aggressive malignant disease, EGFR has emerged as a promising target for cancer therapy. In recent years, several molecular strategies have been explored to modulate either the EGFR itself, or the downstream signal beyond the cell surface receptor. One of the most promising current strategies involves the use of anti-EGFR monoclonal antibodies (mAbs), either alone or in combination with conventional cytotoxic modalities such as chemotherapy or radiotherapy. This review focuses primarily on recent progress in the development of anti-EGFR mAbs, and examines their potential in the treatment of cancer.
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