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1.
Int J Group Psychother ; 51(4): 553-70, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11582900

ABSTRACT

Group therapy is a widely accepted model of care for sex offenders. However, most group therapy takes place in prison utilizing a cognitive-behavioral, psychoeducational model of care. Given that over 250,000 sex offenders are in ambulatory treatment, newer models of care may need to be employed to address their specific needs. I present a naturalistic outpatient study involving my private practice of 109 consecutive sex offenders treated over a 10-year period. A multimodal model of care informed by psychodynamic theory is presented with detailed case material from one group session. Preliminary results of recidivism are presented.


Subject(s)
Paraphilic Disorders/rehabilitation , Psychotherapy, Group/methods , Sex Offenses/psychology , Adult , Aged , Child , Child Abuse, Sexual/rehabilitation , Combined Modality Therapy , Humans , Male , Middle Aged , Psychological Theory , Treatment Outcome
2.
J Med Chem ; 44(7): 1028-34, 2001 Mar 29.
Article in English | MEDLINE | ID: mdl-11297449

ABSTRACT

N-Benzyladriamycin-14-valerate (AD 198) is a semisynthetic anthracycline with experimental antitumor activity superior to that of doxorubicin (DOX). AD 198, unlike DOX, only weakly binds DNA, is a poor inhibitor of topoisomerase II, and circumvents anthracycline-resistance mechanisms, suggesting a unique mechanism of action for this novel analogue. The phorbol ester receptors, protein kinase C (PKC) and beta2-chimaerin, were recently identified as selective targets for AD 198 in vitro. In vitro, AD 198 competes with [3H]PDBu for binding to a peptide containing the isolated C1b domain of PKC-delta (deltaC1b domain). In the present study molecular modeling is used to investigate the interaction of AD 198 with the deltaC1b domain. Three models are identified wherein AD 198 binds into the groove formed between amino acid residues 6-13 and 21-27 of the deltaC1b domain in a manner similar to that reported for phorbol-13-acetate and other ligands of the C1 domain. Two of the identified models are consistent with previous experimental data demonstrating the importance of the 14-valerate side chain of AD 198 in binding to the C1 domain as well as current data demonstrating that translocation of PKC-alpha to the membrane requires the 14-valerate substituent. In this regard, the carbonyl of the 14-valerate participates in hydrogen bonding to the deltaC1b while the acyl chain is positioned for stabilization of the membrane-bound protein-ligand complex in a manner analogous to the acyl chains of the phorbol esters. These studies provide a structural basis for the interaction of AD 198 with the deltaC1b domain and a starting point for the rational design of potential new drugs targeting PKC and other proteins with C1 domains.


Subject(s)
Antibiotics, Antineoplastic/chemistry , Caenorhabditis elegans Proteins , Doxorubicin/chemistry , Isoenzymes/chemistry , Protein Kinase C/chemistry , Receptors, Drug/chemistry , Carrier Proteins , Doxorubicin/analogs & derivatives , Models, Molecular , Protein Binding , Protein Kinase C-delta
3.
Drug Resist Updat ; 4(3): 169-77, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11768330

ABSTRACT

The anthracycline antibiotics doxorubicin (Adriamycin; DOX) and daunorubicin (DNR) continue to be essential components of first-line chemotherapy in the treatment of a variety of solid and hematopoietic tumors. The overall efficacies of DOX and DNR are, however, impeded by serious dose-limiting toxicities, including cardiotoxicity, and the selection of multiple mechanisms of cellular drug resistance. These limitations have necessitated the development of newer anthracyclines whose structural and functional modifications circumvent these impediments. In this review, we will present recent strategies in anthracycline design and assess their potential therapeutic merits. Current anthracycline design has diverged to target either cytoplasmic or nuclear sites. Nuclear targets have been broadened to include not only topoisomerase II (topo II) inhibition through ternary complex stabilization and catalytic inhibition, but also topoisomerase I (topo I) inhibition and transcriptional inhibition. In contrast, cytoplasmic targeting focuses on anthracycline binding to protein kinase C (PKC) regulatory domain with consequent modulation of activity.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Cell Nucleus/drug effects , Cytoplasm/drug effects , Drug Delivery Systems/methods , Animals , Cell Nucleus/enzymology , Cell Nucleus/metabolism , Cytoplasm/enzymology , Cytoplasm/metabolism , Humans
4.
Biochem Pharmacol ; 60(11): 1621-8, 2000 Dec 01.
Article in English | MEDLINE | ID: mdl-11077044

ABSTRACT

N-Benzyladriamycin (AD 288) is a highly lipophilic, semi-synthetic congener of doxorubicin (DOX). Unlike DOX, which stimulates double-stranded DNA scission by stabilizing topoisomerase II/DNA cleavable complexes, AD 288 is a catalytic inhibitor of topoisomerase II, capable of preventing topoisomerase II activity on DNA. The concentration of AD 288 required to inhibit the topoisomerase II-catalyzed decatenation of linked networks of kinetoplast DNA was comparable to that for DOX. However, AD 288 did not stabilize cleavable complex formation or stimulate topoisomerase II-mediated DNA cleavage. In addition, AD 288 inhibited the formation of cleavable complexes by etoposide in a concentration-dependent manner. Human CCRF-CEM cells and murine J774. 2 cells exhibiting resistance against DOX, teniposide, or 3'-hydroxy-3'-deaminodoxorubicin through reduced topoisomerase II activity remained sensitive to AD 288. These studies suggest that AD 288 inhibits topoisomerase II activity by preventing the initial non-covalent binding of topoisomerase II to DNA. Since AD 288 is a potent DNA intercalator, catalytic inhibition is achieved by prohibiting access of the enzyme to DNA binding sites. These results also demonstrate that specific substitutions on the aminosugar of DOX can alter the mechanism of topoisomerase II inhibition.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Doxorubicin/analogs & derivatives , Doxorubicin/pharmacology , Topoisomerase II Inhibitors , Catalysis , DNA/drug effects , DNA/metabolism , DNA Topoisomerases, Type II/metabolism , Dose-Response Relationship, Drug , Drug Interactions , Drug Resistance, Neoplasm , Etoposide/pharmacology , Humans , Tumor Cells, Cultured
5.
Oncol Res ; 10(4): 209-17, 1998.
Article in English | MEDLINE | ID: mdl-9778692

ABSTRACT

N-(2-Chloroethyl)-N-nitrosoureidodaunorubicin (AD 312), a novel semisynthetic compound with combined anthracycline and nitrosourea alkylating functionalities, circumvents resistance conferred by either reduced DNA topoisomerase II (topo II) or increased P-glycoprotein expression with less myelosuppression and cardiotoxicity than adriamycin (doxorubicin; ADR). Cellular resistance to AD 312 could arise from a novel mechanism that confers resistance to both functions simultaneously, or one or more mechanisms common to anthracyclines and/or alkylating agents. The mechanism contributing to AD 312 resistance was investigated following selection of AD 312-resistant murine J774.2 macrophage-like cells and human NCI-H460 non-small-cell lung carcinoma cells. Murine J/312-400 (> 4.7-fold) and human H/312-40 cells (6.3-fold) were cross-resistant to topo II inhibitors (ADR, teniposide, etoposide) and nitrosoureas (carmustine, lomustine) but remained sensitive to vinblastine, colchicine, and camptothecin. There was approximately a twofold decrease in topo II decatenation activity and protein. Decreased net intracellular drug accumulation was not observed. There were no increases in glutathione content or glutathione-S-transferase activity. Increased O6-methylguanine-DNA methyltransferase (MGMT) activity (2.3-fold) was detected in J/312-400, and AD 312 resistance was partially reversed by O6-benzylguanine, a potent inhibitor of MGMT activity. The results suggest that AD 312 resistance arose through selective pressure by both cytotoxic functions in a serial manner.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , DNA Topoisomerases, Type II/drug effects , DNA Topoisomerases, Type II/metabolism , Nitrosourea Compounds/pharmacology , O(6)-Methylguanine-DNA Methyltransferase/drug effects , O(6)-Methylguanine-DNA Methyltransferase/metabolism , Animals , Blotting, Western , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/enzymology , Cells, Cultured , Drug Resistance, Neoplasm , Glutathione/metabolism , Glutathione Transferase/metabolism , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/enzymology , Macrophages/drug effects , Macrophages/enzymology , Mice , Tumor Cells, Cultured
6.
Anticancer Drugs ; 9(1): 58-66, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9491793

ABSTRACT

N-benzyladriamycin-14-valerate (AD 198) is pharmacologically superior to Adriamycin (ADR) based upon comparable cytotoxicity, decreased cardiotoxicity and the ability of AD 198 to circumvent multidrug resistance conferred by either P-glycoprotein overexpression or reduced topoisomerase II activity. AD 198, however, suffers from systemic lability of the 14-O-valerate moiety to enzymatic and non-enzymatic cleavage to yield N-benzyladriamycin (AD 288), which is more similar to ADR in activity. The purpose of this study was to determine whether stability of the ester linkage could be achieved while preserving the favorable characteristics of AD 198 by using a series of N-benzylated ADR congeners containing 14-O-acyl substitutions of incrementally shorter carbon chain lengths. Results from this study indicate that the linear five-carbon valerate substitution is the minimum length necessary to circumvent P-glycoprotein and prevent inhibition of topoisomerase II activity. In addition, although AD 198 is not a pro-drug of AD 288, intracellular 14-O-acyl cleavage appears to contribute to the cytotoxicity of AD 198.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Doxorubicin/analogs & derivatives , Animals , Antibiotics, Antineoplastic/metabolism , Cell Line/drug effects , Doxorubicin/metabolism , Doxorubicin/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Mice , Structure-Activity Relationship
7.
Conn Med ; 61(9): 609-18, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9334516

ABSTRACT

BACKGROUND: Upwards of 7% of cognitively impaired elderly are reported to exhibit sexually disinhibited behaviors. These behaviors may be the result of either a chronic history of sexual disinhibition, regression, or sequel to a stroke, surgical intervention, vascular insult, blow to the head, or cardiac event in which observed cognitive deterioration is the acute symptom. Elderly patients who are sexually disinhibited may exhibit a behavior that makes it difficult to manage them at home or in a nursing home. METHODS: A review of the treatment of sexual disinhibition with neurohormones is presented; guidelines for assessing risk and risk management are proposed; and a five-year study with 39 geriatric out patients with cognitive impairment and sexual disinhibitions reviewed. Case examples of sexual aggressives are followed by treatment recommendations in which an algorithm is presented. RESULTS: The treatment algorithm recommends beginning selective serotonin reuptake inhibitors medication before considering estrogen (preferably a patch) or antiandrogen therapy. The estrogen patch led to excellent treatment results in elderly demented men with sexual disinhibition. CONCLUSIONS: Elderly demented patients who are sexually disinhibited may be managed successfully with neurohormones if SSRI medication proves unsuccessful.


Subject(s)
Estradiol/therapeutic use , Risk Management , Sexual Dysfunctions, Psychological/drug therapy , Sexual Dysfunctions, Psychological/psychology , Aged , Female , Humans , Male
8.
Biochemistry ; 36(9): 2679-85, 1997 Mar 04.
Article in English | MEDLINE | ID: mdl-9054575

ABSTRACT

From a number of studies it has been suggested that positive charge and degree of lipophilicity dictate, or at least influence, whether anthracyclines are recognized by the apparently clinical important mechanism of tumor cell resistance, i.e., P-gp-mediated multidrug resistance. Using a selected series of analogs in which lipophilicity and or positive charge are altered we find the following: (1) Positively-charged anthracyclines as compared to their neutral counterparts are better recognized by MDR+ cells. (2) With increasing lipophilicity charge becomes less important for MDR recognition. (3) In MDR+ cells with a resistance index to Adriamycin (ADR) of 4534, as compared to an MDR- parental line, almost all of the resistance is circumvented (resistance index = 3) with an anthracycline which does not contain a protonatable nitrogen and is highly lipophilic (partition coefficient, log p = > 1.99). (4) As lipophilicity is increased to log p > 1.99 and nuclear binding is decreased, anthracycline localization switches from nuclear to cytoplasmic which most likely indicates a different cytotoxic target and mechanism of action. (5) Cytoplasmically localized anthracyclines appear to distribute also in mitochondria which suggests these organelles as possible new anthracycline targets. In contrast, ADR shows no mitochondrial localization. (6) Photoaffinity analysis suggests that the highly lipophilic analogs, regardless of charge, interfere with NASV-Vp binding to P-gp. This is consistent with the idea that highly lipophilic anthracyclines act as modulators of MDR which may contribute to their mechanism of overcoming this form of resistance. The possible clinical significance of these data is that highly lipophilic anthracyclines are shown to circumvent MDR which most likely reflects their ability to localize in the cytoplasm and affect targets other than nuclear DNA, i.e., mitochondria, and to act as self modulators of MDR. Thus, a new approach to circumventing MDR and other mechanisms of resistance which involve nuclear targets is the use of active anthracyclines which are highly lipophilic and localize in the cytoplasm/mitochondria.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/chemistry , Anthracyclines/chemistry , Drug Resistance, Multiple , Affinity Labels , Animals , Anthracyclines/metabolism , Anthracyclines/toxicity , Cell Line , Cell Nucleus/chemistry , Fibroblasts , Growth Inhibitors/toxicity , Intracellular Fluid/metabolism , Lipid Metabolism , Myocardium , Rats , Tumor Cells, Cultured
9.
Anticancer Drugs ; 5(6): 623-33, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7888699

ABSTRACT

The novel anthracycline N-benzyladriamycin-14-valerate (AD 198) circumvents P-glycoprotein (P-gp)- and altered topoisomerase II-mediated drug resistance. Nevertheless, AD 198-resistant (AD 198R) murine J774.2 cells overexpressed P-gp, were cross-resistant to other drugs through reduced accumulation and were rendered sensitive by continuous exposure to verapamil. Intracellular AD 198 was, however, similar in sensitive and resistant cells. Consequently, the ability of P-gp to confer AD 198 resistance was examined. It was observed that (i) AD 198 resistance in AD 198R cells grown without drug for 15 months declined by 60% with only a 10-15% loss of vinblastine cross-resistance and P-gp expression; (ii) a cloned AD 198R P388 mouse leukemic cell line did not express P-gp; and (iii) verapamil did not attenuate resistance against high-dose, short-term exposure to AD 198. Therefore, AD 198 resistance appeared to be P-gp-independent despite P-gp overexpression. Antioxidant enzyme and topoisomerase II activities remained unchanged between sensitive and resistance cells. These results suggest that AD 198 resistance was conferred by a novel mechanism.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/analysis , DNA Topoisomerases, Type II/analysis , Doxorubicin/analogs & derivatives , Affinity Labels , Animals , Azides , Cells, Cultured/drug effects , Cells, Cultured/metabolism , Dihydropyridines , Dose-Response Relationship, Drug , Doxorubicin/metabolism , Doxorubicin/pharmacology , Drug Resistance , Immunoblotting , Mice , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism , Verapamil/pharmacology
10.
Oncol Res ; 5(6-7): 229-34, 1993.
Article in English | MEDLINE | ID: mdl-7907237

ABSTRACT

N-Benzyladriamycin-14-valerate (AD 198)-resistant murine J774.2 macrophage-like cells (A300) exhibited a novel mechanism of resistance in which P-glycoprotein was overexpressed without decreased AD 198 accumulation. Cross-resistance to Adriamycin (ADR), N-benzyladriamycin, and Adriamycin-14-valerate was due, at least in part, to reduced accumulation, suggesting that circumvention of P-glycoprotein-mediated transport was associated with extreme lipophilicity conferred by both substitutions. Thus, unlike multidrug resistance mediated by either P-glycoprotein, the multidrug resistance-associated protein (MRP), or decreased topoisomerase II activity, cross-resistance in A300 cells was highly structure-specific. In order to further characterize the specificity of AD 198 resistance, the cytotoxicity, accumulation, and intracellular localization of a series of 3'-morpholinyl, 3'-deamino and halogenated ADR congeners that have been reported to circumvent MDR was determined in AD 198-resistant J774.2 and P388 AD 198-resistant cells. Cross-resistance correlating with increased AD 198 resistance was observed for 2'-bromo-4'-epi-hydroxy-daunomycin (13-fold), morpholinyl doxorubicin (24-fold), and 4'-iodo-4'-deoxydoxorubicin (2.8-fold), but was attributable to decreased accumulation. Cross-resistance to 3'-hydroxy-14-O-palmitoyl-doxorubicin (6-fold) was not due to reduced accumulation. No cross-resistance was observed for the highly cytotoxic metabolite of WP474, 3'-hydroxyldoxorubicin (hydroxyrubicin; WP159), nor for the much less cytotoxic 3'-O-benzylated congeners, including 3'-O-benzyl-doxorubicin-14-valerate. These findings indicate that AD 198 resistance confers cross-resistance to compounds that, like AD 198, localize in the cytoplasm but are metabolized to highly cytotoxic, nuclear-localizing compounds.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Doxorubicin/analogs & derivatives , Drug Resistance , Epirubicin/analogs & derivatives , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Animals , Carrier Proteins/physiology , Doxorubicin/pharmacology , Membrane Glycoproteins/physiology , Mice , Structure-Activity Relationship , Tumor Cells, Cultured
11.
Cancer Res ; 52(12): 3409-17, 1992 Jun 15.
Article in English | MEDLINE | ID: mdl-1350753

ABSTRACT

N-Benzyladriamycin-14-valerate (AD 198) is a highly lipophilic analogue of Adriamycin with novel cytotoxic mechanisms, greater in vivo antitumor activity, and the ability to circumvent multidrug resistance due to P-glycoprotein-mediated drug efflux or decreased topoisomerase II activity. To identify the mechanism(s) which may confer AD 198 resistance, J774.2 mouse macrophage-like cells were selected for growth in cytotoxic levels of AD 198 (AD 198R). AD 198R cells exhibited over-expression of the mdr1b (P-glycoprotein) gene, cross-resistance to Adriamycin and vinblastine, and potentiation of drug cytotoxicity by verapamil. However, net intracellular accumulation of AD 198 in AD 198R cells was unchanged compared to parental cells, while Adriamycin and vinblastine accumulations were reduced 40% and 95%, respectively. AD 198 was localized in the perinuclear region of the cytoplasm in both parental and AD 198R cells, with additional vesicular compartmentalization in AD 198R cells. Verapamil-induced reversal of AD 198 resistance coincided with some drug redistribution from cytoplasmic vesicles, but without redistribution of AD 198 into the nucleus. These results suggest that AD 198 resistance was not conferred through a P-glycoprotein-mediated reduction in intracellular drug accumulation but through other cytoplasmic mechanisms, including, but not limited to, drug compartmentalization.


Subject(s)
Doxorubicin/analogs & derivatives , Macrophages/metabolism , Membrane Glycoproteins/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Animals , Biotransformation , Cells, Cultured , Doxorubicin/metabolism , Doxorubicin/pharmacokinetics , Drug Resistance/genetics , Flow Cytometry , Mice , Microscopy, Fluorescence , RNA, Messenger/metabolism , Verapamil/pharmacology , Vinblastine/metabolism
12.
Oncol Res ; 4(8-9): 341-7, 1992.
Article in English | MEDLINE | ID: mdl-1362503

ABSTRACT

N-Benzyladriamycin-14-valerate (AD 198) is a highly hydrophobic analogue of Adriamycin (ADR) which can circumvent multidrug resistance (MDR) in various cell lines. Unlike ADR, AD 198 avoids extrusion by P-glycoprotein (P-gp) in AD 198-resistant murine macrophage-like J774.2 cells and localizes in the cytoplasm. To determine the structural modification(s) responsible for these different characteristics, intracellular accumulation and distribution of ADR, AD 198, and the two half-substituted AD 198 congeners. N-benzyladriamycin (AD 288) and adriamycin-14-valerate (AD 48), were analyzed in AD 198-sensitive (J774.2) and -resistant (A300) cells. A300 cells exhibited cross-resistance to and reduced accumulation of ADR, AD 48, and AD 288. ADR and AD 288 rapidly localized in the nuclei of parental and A300 cells, while AD 48 and AD 198 localized in the cytoplasm. AD 48 redistributed into nuclei and cytoplasm of both cell lines, but AD 198 maintained a punctate cytoplasmic distribution in A300 cells. These results suggest that both the N-benzyl and C14-valerate substitutions of AD 198 are required for P-gp circumvention and stable cytoplasmic localization in A300 cells, probably as a result of differing intracellular drug trafficking.


Subject(s)
Doxorubicin/analogs & derivatives , Drug Resistance , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Animals , Biotransformation , Carrier Proteins/metabolism , Cell Division/drug effects , Cytoplasm/metabolism , Doxorubicin/pharmacokinetics , Doxorubicin/pharmacology , Membrane Glycoproteins/metabolism , Mice , Microscopy, Fluorescence , Neoplasm Proteins/metabolism , Structure-Activity Relationship , Tumor Cells, Cultured
13.
Mol Cell Biol ; 10(7): 3596-606, 1990 Jul.
Article in English | MEDLINE | ID: mdl-1972547

ABSTRACT

In multidrug-resistant mouse J774.2 cells, the differential overproduction of functionally distinct phosphoglycoprotein isoforms reflects the amplification or transcriptional activation or both of two mdr gene family members, mdr1a and mdr1b. The mdr1a gene is a complex transcriptional unit whose expression is associated with multiple transcript sizes. Independently selected multidrug-resistant J774.2 cell lines differentially overexpress either 4.6- and 5.0-kilobase (kb) or 4.7- and 5.1-kb mdr1a transcripts. However, abundant overproduction of the mdr1a gene product was observed only in cell lines which overexpressed the 4.6- and 5.0-kb mRNAs. In order to determine the basis for mdr1a transcript heterogeneity and the relationship between transcript size and steady-state mdr1a protein levels, genomic and cDNA sequence analyses of the 5' and 3' ends of the mdr1a gene were carried out. Promoter sequence analysis and primer extension mapping indicated that mdr1a transcripts were differentially initiated from two putative promoters to generate either 5.1- and 4.7-kb or 5.0- and 4.6-kb transcripts in four multidrug-resistant J774.2 cell lines. Sequence analysis of 3' cDNA variants and a 3' genomic fragment revealed that the 5.1- and 5.0-kb mRNAs had identical 3'-untranslated regions which differed from those of the 4.7- and 4.6-kb mRNAs as a result of the utilization of a more downstream alternative poly(A) addition signal. Transcript initiation from the putative upstream promoter correlated with a 70 to 85% decrease in steady-state mdr1a protein levels relative to transcript levels. In addition, the identification of putative AP-1 and AP-2 promoter elements suggests a possible role for protein kinase A and protein kinase C in the regulation of mdr1a. The implications of these findings for mdr gene expression and regulation are discussed.


Subject(s)
Drug Resistance/genetics , Membrane Glycoproteins/genetics , Promoter Regions, Genetic , Transcription, Genetic , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Amino Acid Sequence , Animals , Base Sequence , Cell Line , Cloning, Molecular , Exons , Genetic Variation , Humans , Introns , Mice , Molecular Sequence Data , Nucleic Acid Hybridization , Oligonucleotide Probes , Polymerase Chain Reaction , Restriction Mapping , Sequence Homology, Nucleic Acid
14.
J Biol Chem ; 264(27): 16054-8, 1989 Sep 25.
Article in English | MEDLINE | ID: mdl-2570778

ABSTRACT

In multidrug-resistant murine J774.2 cells, the mdr1a and mdr1b genes encode the 120- and 125-kDa P-glycoprotein precursors, respectively (Hsu, S. I., Lothstein, L., and Horwitz, S.B. (1989) J. Biol. Chem. 264, 12053-12062). It is shown here that a J774.2 cell line selected for vinblastine resistance (J7.V3) switched from the 125- to 120-kDa precursor when cells that were maintained in 20 nM vinblastine were grown in 40 nM vinblastine for 20 months. The rate of switching was accelerated by growing cells in higher levels of vinblastine. These findings suggest that cells which express mdr1a have a selective growth advantage compared to cells which express mdr1b. Consistent with this hypothesis, the switching event that occurs in cells maintained at 40 nM vinblastine was correlated with 3.5-5-fold higher levels of resistance to vinblastine, taxol, and doxorubicin in the absence of any detectable increase in the amount of immunoreactive P-glycoprotein. These findings suggest that P-glycoproteins derived from mdr1a and mdr1b are functionally distinct.


Subject(s)
Drug Resistance/genetics , Genes , Membrane Glycoproteins/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Animals , Cell Line , Kinetics , Macrophages , Membrane Glycoproteins/isolation & purification , Mice , Protein Precursors/genetics , Protein Precursors/isolation & purification , Vinblastine/pharmacology
15.
J Biol Chem ; 264(20): 12053-62, 1989 Jul 15.
Article in English | MEDLINE | ID: mdl-2473069

ABSTRACT

A hallmark of the multidrug-resistant phenotype is the overproduction of a family of 130-180-kDa integral membrane phosphoglycoproteins collectively called P-glycoprotein. Gene-specific hybridization probes were derived from three classes of mouse P-glycoprotein cDNAs. These probes revealed the differential amplification and/or transcriptional activation of three distinct but closely related mdr genes (mdr1a, mdr1b, and mdr2) in independently selected multidrug-resistant J774.2 mouse cell lines. Overexpression of mdr1a and mdr1b was found to correlate, in general, with the differential overproduction of either a 120- or 125-kDa P-glycoprotein precursor, respectively. This same correlation was observed in a single cell line during the course of stepwise selection for resistance to vinblastine in which a switch in gene expression from mdr1b to mdr1a resulted in a switch from the 125- to 120-kDa P-glycoprotein precursor. These findings suggest that differential overexpression of distinct mdr genes which encode unique P-glycoprotein isoforms is a possible mechanism for generating diversity in the multidrug-resistant phenotype.


Subject(s)
Drug Resistance/genetics , Gene Expression Regulation , Membrane Glycoproteins/genetics , Multigene Family , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Amino Acid Sequence , Animals , Base Sequence , Blotting, Northern , Blotting, Southern , Cell Line , Cricetinae , Humans , Mice , Molecular Sequence Data , RNA/analysis , Sequence Homology, Nucleic Acid
16.
Int J Group Psychother ; 39(2): 237-53, 1989 Apr.
Article in English | MEDLINE | ID: mdl-2707935

ABSTRACT

A group therapy model was formulated for exploring the intersubjective processes of adolescents and young adults whose group bonds had been fragmented by their severe emotional illnesses. The model involved having adolescents and young adults who were psychiatric inpatients make video self-portraits; that is, videotapes which focused on various aspects of their emotional pathology. These tapes were then presented before a larger group of nine patients for discussion. The video team method is shown to aid in self-disclosure and facilitate the working through of severe emotional conflicts in this age group. It is an especially useful method with more severely disturbed patients for whom narcissistic self pathology is a prominent feature.


Subject(s)
Group Processes , Mental Disorders/therapy , Psychotherapy, Group/methods , Self Concept , Videotape Recording , Adaptation, Psychological , Adolescent , Adult , Denial, Psychological , Female , Humans , Male , Mental Disorders/psychology , Suicide/psychology
17.
Leukemia ; 2(7): 453-8, 1988 Jul.
Article in English | MEDLINE | ID: mdl-2899184

ABSTRACT

Mouse macrophage-like J774.2 cells were selected for resistance to colchicine and examined by molecular/cytogenetic analysis to determine whether the acquisition of the multidrug resistant (mdr) phenotype was associated with specific chromosomal rearrangements. Cytogenetic studies of the J774.2 parental and two colchicine-resistant (CLCR) sublines--J7.Cl-30 (770-fold CLCR) and J7.Cl-100 (2500-fold CLCR)--demonstrated specific numeric and structural karyotypic alterations accompanying the emergence of mdr. The parental cells demonstrated a modal chromosome number of 63, while the modal number of the J7.Cl-30 subline was 53. The most striking difference between the parental and J7.Cl-30 subline was the presence of an average of 60 double minutes (DMs) per cell in the CLCR cells. The 2500-fold resistant J7.Cl-100 subline displayed a modal number of 50, which included structural rearrangements involving chromosomes 2 and 7 and concomitant replacement of DMs by a homogeneously staining region (HSR). Southern blotting analysis demonstrated a approximately 35-fold amplification of P-glycoprotein homologous sequences in the J7.Cl-30 subline and approximately 70-fold amplification in the J7.Cl-100 subline. Chromosomal in situ hybridization localized the amplified P-glycoprotein sequences to DMs (J7.Cl-30) and the HSR (J7.Cl-100) in these CLCR sublines. Our results suggest that CLCR in J774.2 cells results from overexpression of P-glycoprotein via gene amplification which was accompanied by chromosomal evolution from DMs to an HSR.


Subject(s)
Chromosome Aberrations , Colchicine/pharmacology , Drug Resistance , Neoplasms, Experimental/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Animals , Cell Line , Gene Amplification , Macrophages/ultrastructure , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Mice , Nucleic Acid Hybridization
19.
Proc Natl Acad Sci U S A ; 85(11): 3762-6, 1988 Jun.
Article in English | MEDLINE | ID: mdl-2897689

ABSTRACT

A family of P-glycoproteins are overproduced in multidrug-resistant cells derived from the murine macrophage-like line J774.2. To determine whether individual family members are overproduced in response to different drugs, the P-glycoprotein precursors in several independently isolated cell lines, which were selected for resistance to vinblastine or taxol, were compared. Individual cell lines selected with vinblastine overproduced P-glycoprotein precursors of either 120 or 125 kDa. Taxol-selected cell lines overproduced either the 125-kDa precursor or both precursors simultaneously. Two similar but distinct peptide maps for the mature P-glycoproteins were observed. These maps corresponded to each precursor regardless of the drug used for selection. One vinblastine-resistant cell line switched from the 125- to the 120-kDa precursor when grown in increasing concentrations of drug. This change coincided with the overexpression of a distinct subset of mRNA species that code for P-glycoprotein. It is concluded that precursor expression is not drug-specific. These data suggest that individual overproduced P-glycoprotein family members are translated as distinct polypeptides. The results may help to explain the diversity in the multidrug-resistant phenotype.


Subject(s)
Drug Resistance , Membrane Glycoproteins/metabolism , Protein Precursors/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Alkaloids/pharmacology , Animals , Cell Line , Colchicine/pharmacology , Gene Expression Regulation , Membrane Glycoproteins/genetics , Mice , Molecular Weight , Paclitaxel , Peptide Mapping , Protein Precursors/genetics , RNA, Messenger/genetics , Vinblastine/pharmacology
20.
Arch Sex Behav ; 15(5): 401-15, 1986 Oct.
Article in English | MEDLINE | ID: mdl-3789904

ABSTRACT

This paper reports on a survey approach to the study of the aging (40 years of age and older) female requesting sex reassignment surgery (SRS). A profile of 13 cases presenting at a cross-section of gender identity clinics in North America is presented. The mid-life SRS applicant is also compared on selected characteristics with a younger female transsexual group and with the aging male sex change applicant. Findings suggest that the mid-life female SRS applicant is closely akin to the aging, conflicted homosexual, whereas the mid-life male SRS applicant appears more closely associated with the aging transvestite.


Subject(s)
Genitalia/surgery , Surgery, Plastic/psychology , Transsexualism/psychology , Women/psychology , Adult , Castration , Female , Humans , Male , Middle Aged
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