1: Neoplasma  2002;49(4):272-7

 

Deactivation of P-glycoprotein by a novel compound, oxalyl bis (N-phenyl)

hydroxamic acid.

 

Choudhuri SK.

 

Department of Environmental Carcinogenesis & Toxicology; Chittaranjan National

Cancer Institute, Calcutta, 700-026 India. soumitra01@vsnl.net

 

A plasma membrane glycoprotein (P-gp) of 170 kd is over-expressed in most of the

drug resistant cells. P-gp is encoded in humans by the gene mdrl and is thought

to function as a broad substrate ATP-dependent drug efflux pump. P-gp is also

present in many types of normal cells. A good number of chemicals inhibit or

deactivate P-gp and thus reverse multidrug resistance (MDR). Most of the

reported resistance modifying agents (RMAs) are effective in vitro and have

adverse effect on the hosts. Hence, the development of nontoxic RMA is of

immense importance in the field of cancer chemotherapy. With this end in view, a

nontoxic resistance modifying agent, viz., oxalyl bis (N-phenyl) hydroxamic acid

(OPHA) has been developed on the basis of the structural commonalities of the

reported RMAs. We reported earlier that OPHA reverses doxorubicin resistance in

vitro and also reduces glutathione and glutathione S-transferase in a non P-gp

expressing cell line. In the present report, the inhibition of P-gp by the

compound, OPHA in human cervical cancer cell line, HeLa, has been described by

western blotting, study of immunofluorescence and enzyme linked

immunofluorescence assay (ELISA). The inhibition of P-gp by OPHA is

significantly higher than that of verapamil. The high IC50 values of OPHA

against different cell lines indicate the non toxic nature of the compound. This

work underscores the possibility of using the present hydroxamic acid derivative

as the nontoxic modulator of the MDR phenotype.

 

PMID: 12382028 [PubMed - in process]

 

 

 

2: Int J Radiat Oncol Biol Phys  2002 Nov 1;54(3):895

 

Fractionated irradiation of H69 small-cell lung cancer cells causes stable

radiation and drug resistance with increased MRP1, MRP2, and topoisomerase

IIalpha expression.

 

Henness S, Davey M, Harvie R, Davey R.

 

Bill Walsh Cancer Research Laboratories, Medical Oncology Department, Royal

North Shore Hospital, St. Leonards, Australia

 

PURPOSE: After standard treatment with chemotherapy and radiotherapy, small-cell

lung cancer (SCLC) often develops resistance to both treatments. Our aims were

to establish if fractionated radiation treatment alone would induce radiation

and drug resistance in the H69 SCLC cell line, and to determine the mechanisms

of resistance.METHODS AND MATERIALS: H69 SCLC cells were treated with

fractionated X-rays to an accumulated dose of 37.5 Gy over 8 months to produce

the H69/R38 subline. Drug and radiation resistance was determined using the MTT

(3,-4,5 dimethylthiazol-2,5 diphenyltetrazolium bromide) cell viability assay.

Protein expression was analyzed by Western blot.RESULTS: The H69/R38 subline was

resistant to radiation (2.0 +/- 0.2-fold, p < 0.0001), cisplatin (14 +/- 7-fold,

p < 0.001), daunorubicin (6 +/- 3-fold, p < 0.05), and navelbine (1.7 +/-

0.15-fold, p < 0.02). This was associated with increased expression of the

multidrug resistance-associated proteins, MRP1 and MRP2, and topoisomerase

IIalpha and decreased expression of glutathione-S-transferase pi (GSTpi) and

bcl-2 and decreased cisplatin accumulation. Treatment with 4 Gy of X-rays

produced a 66% decrease in MRP2 in the H69 cells with no change in the H69/R38

cells. This treatment also caused a 5-fold increase in topoisomerase IIalpha in

the H69/R38 cells compared with a 1.5-fold increase in the H69

cells.CONCLUSIONS: Fractionated radiation alone can lead to the development of

stable radiation and drug resistance and an altered response to radiation in

SCLC cells.

 

PMID: 12377343 [PubMed - in process]

 

 

 

3: Blood  2002 Oct 15;100(8):2703-7

 

Negative prognostic value of glutathione S-transferase (GSTM1 and GSTT1)

deletions in adult acute myeloid leukemia.

 

Voso MT, D'Alo' F, Putzulu R, Mele L, Scardocci A, Chiusolo P, Latagliata R,

Lo-Coco F, Rutella S, Pagano L, Hohaus S, Leone G.

 

Istituto di Ematologia, Universita' Cattolica S. Cuore and Dipartmento di

Biotecnologie Cellulari ed Ematologia, Universita' La Sapienza, Rome, Italy.

 

Glutathione S-transferases (GSTs) are enzymes involved in the detoxification of

several environmental mutagens, carcinogens, and anticancer drugs. GST

polymorphisms resulting in decreased enzymatic activity have been associated

with several types of solid tumors. We determined the prognostic significance of

the deletion of 2 GST subfamilies genes, M1 and T1, in patients with acute

myeloid leukemia (AML). Using polymerase chain reactions, we analyzed the GSTM1

and GSTT1 genotype in 106 patients with AML (median age, 60.5 years; range,

19-76 years). The relevance of GSTM1 and GSTT1 homozygous deletions was studied

with respect to patient characteristics, response to therapy, and survival.

Homozygous deletions resulting in null genotypes at the GSTM1 and GSTT1 loci

were detected in 45 (42%) and 30 (28%) patients, respectively. The double-null

genotype was present in 19 patients (18%). GST deletions predicted poor response

to chemotherapy (P =.04) and shorter survival (P =.04). The presence of at least

one GST deletion proved to be an independent prognostic risk factor for response

to induction treatment and overall survival in a multivariate analysis including

age and karyotype (P =.02). GST genotyping was of particular prognostic value in

the cytogenetically defined intermediate-risk group (P =.003). In conclusion,

individuals with GSTM1 or GSTT1 deletions (or deletions of both) may have an

enhanced resistance to chemotherapy and a shorter survival. (Blood.

2002;100:2703-2707)

 

PMID: 12351375 [PubMed - in process]

 

 

 

4: J Biol Chem  2002 Sep 23; [epub ahead of print]

 

Neuronal leucine-rich repeat protein-3 amplifies MAP kinase activation by EGF

through a carboxyl-terminal region containing endocytosis motifs.

 

Fukamachi K, Matsuoka Y, Ohno H, Hamaguchi T, Tsuda H.

 

Experimental Pathology and Chemotherapy Division, National Cancer Center

Research Institute, Tokyo 104-0045.

 

Neuronal leucine-rich repeat protein-3 (NLRR-3) belongs to the LRR superfamily.

We have reported that rat NLRR-3 gene expression is regulated mainly through the

Ras-mitogen-activated protein kinase (MAPK) signaling pathway. NLRR-3 was found

to enhance phosphorylation of MAPK when COS-7 cells were transfected with NLRR-3

and stimulated with a low concentration (0.01 ng/ml) of epidermal growth factor

(EGF), but the amplification of MAPK phosphorylation by NLRR-3 was no longer

observed when the carboxyl terminal 30 amino acid stretch that contains

clathrin-mediated endocytosis motifs was deleted. A green fluorescent

protein-tagged NLRR-3 localized at the plasma membrane was efficiently

internalized in COS-7 cells, but internalization of a carboxyl terminal-deleted

version (NLRR*C) was less efficient. The presence of clathrin-adaptor protein

complexes containing NLRR-3 in brain lysate was confirmed by immunoprecipitation

and glutathione S-transferase pull-down experiments, and affinity column

chromatography revealed that the carboxyl terminal region of NLRR-3 interacts

with -adaptin. We propose that NLRR-3 potentiates Ras-MAPK signaling by

facilitating internalization of EGF in clathrin-coated vesicles.

 

PMID: 12297494 [PubMed - as supplied by publisher]

 

 

 

5: Eur J Pharmacol  2002 Sep 13;451(2):203

 

Protection by a radical scavenger edaravone against cisplatin-induced

nephrotoxicity in rats.

 

Sueishi K, Mishima K, Makino K, Itoh Y, Tsuruya K, Hirakata H, Oishi R.

 

Department of Hospital Pharmacy, Faculty of Medicine, Kyushu University, 3-1-1,

Maidashi, Higashi-ku, 812-8582, Fukuoka, Japan

 

Acute renal failure is a dose-limiting factor of cisplatin chemotherapy. Here,

we show the protective effect of edaravone, a recently developed radical

scavenger for clinical use, against cisplatin-induced renal dysfunction in rats.

A marked increase in blood urea nitrogen and creatinine in serum, and

histological changes including vacuolation, necrosis and protein casts were

observed in proximal renal tubules at the fourth day after cisplatin injection

(5-10 mg/kg). Repeated injection of edaravone (1-10 mg/kg, i.v. twice a day for

3 days) reversed the cisplatin-induced elevation of blood urea nitrogen and

creatinine, and morphological changes in a dose-dependent manner. In particular,

the protective effect of edaravone was almost complete at 10 mg/kg. Moreover,

the compound was still fully effective, when it was administered only at the

second day after cisplatin injection. On the other hand, the glutathione content

in renal tissues lowered at the fourth day after cisplatin injection, which was

reversed by the late treatment with edaravone. These findings suggest that the

clinically available radical scavenger edaravone is potentially useful for the

prevention of cisplatin-induced renal toxicity.

 

PMID: 12231392 [PubMed - in process]

 

 

 

6: J Biol Chem  2002 Sep 10; [epub ahead of print]

 

Glutathione influences c-Myc-induced apoptosis in M14 human melanoma cells.

 

Biroccio A, Benassi B, Filomeni G, Amodei S, Marchini S, Chiorino G, Rotilio G,

Zupi G, Ciriolo MR.

 

Department of Experimental Chemotherapy Laboratory, Regina Elena Cancer

Institute, Rome, Rome 00158.

 

The present paper aims at dissecting the mechanisms by which the down-regulation

of c-Myc induces programmed cell death in melanoma cells. In stable and

doxycycline-inducible M14 melanoma cells, down-regulation of c-Myc induced

apoptosis subsequent to a decrease in the intracellular reduced glutathione

content and a concomitant accumulation of its oxidized form. This redox

alteration was associated with a decrease of the enzyme activities of

g-glutamyl-cysteine synthetase and NADPH-dependent GSSG-reductase, and to a

consequent glutathione release in the extracellular medium. Cytochrome c was

released into the cytosol at very early stages of apoptosis induction, long

before detectable production of reactive oxygen species and activation of

caspase-9 and -3. Macroarray analysis revealed that down-regulation of c-Myc

produced striking changes of gene expression in the section related to

metabolism; where the expression of g-glutamyl-cysteine synthetase and

GSSG-reductase was found to be significantly reduced. Addition of

N-acetyl-L-cysteine or glutathione ethyl-ester was able to inhibit the apoptotic

process, thus confirming the key role of glutathione in the programmed cell

death induced by c-Myc.

 

PMID: 12226097 [PubMed - as supplied by publisher]

 

 

 

7: Cancer  2002 Aug 1;95(3):641-55

 

Evaluation of the efficiency of chemotherapy in in vivo orthotopic models of

human glioma cells with and without 1p19q deletions and in C6 rat orthotopic

allografts serving for the evaluation of surgery combined with chemotherapy.

 

Branle F, Lefranc F, Camby I, Jeuken J, Geurts-Moespot A, Sprenger S, Sweep F,

Kiss R, Salmon I.

 

Department of Oncology, Erasmus University Hospital, Brussels, Belgium.

 

BACKGROUND: Malignant gliomas of the central nervous system remain associated

with dismal prognoses because of their diffuse invasion of the brain parenchyma.

Very few experimental models that mimic clinical reality are available today to

test potentially new therapies. The authors set up experimental in vivo glioma

models of anaplastic astrocytomas of human and rat origins and anaplastic

oligodendroglioma of human origin. Standard hospital chemotherapies were

employed to test the validity of these models. METHODS: Three glioma cells lines

obtained from the American Type Culture Collection (i.e., human Hs683 and U373

cells and rat C6 cells) were implanted into nude mouse brains (Hs683 and U373

cells) and rat brains (C6 cells). The astrocytic nature, as opposed to the

oligodendrocytic nature, of the Hs683 and U373 models was investigated by using

quantitative (computer-assisted microscopy) immunohistochemical

characterizations of nestin, vimentin, glutathione-S-transferase alpha

(GSTalpha), GSTmu, GSTpi, and p53 expression. Comparative genomic hybridization

(CGH) was employed to investigate 1p19q losses. Chronic administrations of

carmustine (BCNU), fotemustin, or temozolomide were assayed in the xenografted

U373 and Hs683 models. Both BCNU-related chemotherapy and surgery were assayed

in the C6 model. RESULTS: The quantitative phenotypic analyses pointed to the

oligodendroglial nature of the Hs683 cell line and the astrocytic nature of the

U373 cell line. The Hs683 cells exhibited 1p19q losses, whereas the U373 cells

did not. BCNU, fotemustin, and temozolomide dramatically increased the time of

survival of the Hs683 oligodendroglioma-bearing mice, whereas temozolomide only

induced a weak but nevertheless statistically significant increase in the U373

glioma-bearing mice. In the C6 rat glioma model, surgery and BCNU chemotherapy

were more efficient than either treatment alone. CONCLUSIONS: The in vivo models

of gliomas of the central nervous system developed in the current work best

mimicked clinical reality. They can be used either to identify new therapies

against human gliomas or to optimize existing therapies. Copyright 2002 American

Cancer Society.

 

PMID: 12209758 [PubMed - indexed for MEDLINE]

 

 

 

8: Cancer Res  2002 Sep 1;62(17):4916-21

 

FK228 (depsipeptide) as a natural prodrug that inhibits class I histone

deacetylases.

 

Furumai R, Matsuyama A, Kobashi N, Lee KH, Nishiyama M, Nakajima H, Tanaka A,

Komatsu Y, Nishino N, Yoshida M, Horinouchi S.

 

Department of Biotechnology, The University of Tokyo, Tokyo 113-8657, Japan.

 

FK228 is a histone deacetylase (HDAC) inhibitor, the molecular mechanism of

inhibition of which has been unknown. Here we show that reduction of an

intramolecular disulfide bond of FK228 greatly enhanced its inhibitory activity

and that the disulfide bond was rapidly reduced in cells by cellular reducing

activity involving glutathione. Computer modeling suggests that one of the

sulfhydryl groups of the reduced form of FK228 (redFK) interacts with the

active-site zinc, preventing the access of the substrate. HDAC1 and HDAC2 were

more strongly inhibited by redFK than HDAC4 and HDAC6. redFK was less active

than FK228 in inhibiting in vivo HDAC activity, due to rapid inactivation in

medium and serum. Thus, FK228 serves as a stable prodrug to inhibit class I

enzymes and is activated by reduction after uptake into the cells. The

glutathione-mediated activation also implicates its clinical usefulness for

counteracting glutathione-mediated drug resistance in chemotherapy.

 

PMID: 12208741 [PubMed - indexed for MEDLINE]

 

 

 

9: Bone Marrow Transplant  2002 Aug;30(3):135-40

 

Synergistic cytotoxicity of buthionine sulfoximine (BSO) and intensive melphalan

(L-PAM) for neuroblastoma cell lines established at relapse after myeloablative

therapy.

 

Anderson CP, Reynolds CP.

 

Division of Hematology-Oncology, Childrens Hospital Los Angeles, CA 90027, USA.

 

Patients with high-risk neuroblastoma (NB) initially respond to aggressive,

alkylator-based therapy only to die from recurrent disease that is refractory to

chemotherapy, including alkylating agents. We examined the ability of buthionine

sulfoximine (BSO)-mediated glutathione (GSH) depletion to modulate melphalan

(L-PAM) resistance in five NB cell lines established after progressive disease

following myeloablative therapy (high-dose melphalan, carboplatin, etoposide and

total body irradiation) supported by autologous hematopoietic stem cell

transplant (AHSCT), and in 15 NB cell lines established at diagnosis or after

non-myeloablative therapy (pre-AHSCT). Four of five post-AHSCT NB cell lines and

10 of 15 pre-AHSCT NB cell lines were sensitive to single agent BSO (LC(90) <300

microM BSO), while two of five post-AHSCT lines and one of 15 pre-AHSCT lines

showed high-level resistance to L-PAM (LC(90)>30 microM). Fixed ratio analysis

demonstrated BSO/L-PAM synergy (combination index <1) for all five post-AHSCT

and for all 15 pre-AHSCT cell lines tested. Multi-log cytotoxicity (often

exceeding four logs of cell kill) was observed in post-AHSCT L-PAM-resistant

cell lines (including p53 non-functional lines) only when clinically achievable

concentrations of BSO were combined with myeloablative concentrations of L-PAM.

We conclude that most neuroblastoma cell lines, including post-AHSCT NB cell

lines that are highly resistant to myeloablative levels of L-PAM and lack p53

function, are sensitive to clinically achievable concentrations of L-PAM and

BSO. However, some L-PAM-resistant NB cell lines (especially those lacking p53

function) require dose escalation of L-PAM to myeloablative concentrations in

order to demonstrate significant synergistic cytotoxicity. Thus, optimal

clinical application of BSO/L-PAM may require AHSCT.

 

PMID: 12189530 [PubMed - in process]

 

 

 

10: Br J Cancer  2002 Jul 29;87(3):251-7

 

Protein expression profiles indicative for drug resistance of non-small cell

lung cancer.

 

Volm M, Koomagi R, Mattern J, Efferth T.

 

German Cancer Research Centre, Heidelberg, Germany.

 

Data obtained from multiple sources indicate that no single mechanism can

explain the resistance to chemotherapy exhibited by non-small cell lung

carcinomas. The multi-factorial nature of drug resistance implies that the

analysis of comprising expression profiles may predict drug resistance with

higher accuracy than single gene or protein expression studies. Forty cellular

parameters (drug resistance proteins, proliferative, apoptotic, and angiogenic

factors, products of proto-oncogenes, and suppressor genes) were evaluated

mainly by immunohistochemistry in specimens of primary non-small cell lung

carcinoma of 94 patients and compared with the response of the tumours to

doxorubicin in vitro. The protein expression profile of non-small cell lung

carcinoma was determined by hierarchical cluster analysis and clustered image

mapping. The cluster analysis revealed three different resistance profiles. The

frequency of each profile was different (77, 14 and 9%, respectively). In the

most frequent drug resistance profile, the resistance proteins

P-glycoprotein/MDR1 (MDR1, ABCB1), thymidylate-synthetase,

glutathione-S-transferase-pi, metallothionein,

O6-methylguanine-DNA-methyltransferase and major vault protein/lung

resistance-related protein were up-regulated. Microvessel density, the

angiogenic factor vascular endothelial growth factor and its receptor FLT1, and

ECGF1 as well were down-regulated. In addition, the proliferative factors

proliferating cell nuclear antigen and cyclin A were reduced compared to the

sensitive non-small cell lung carcinoma. In this resistance profile, FOS was

up-regulated and NM23 down-regulated. In the second profile, only three

resistance proteins were increased (glutathione-S-transferase-pi,

O6-methylguanine-DNA-methyltransferase, major vault protein/lung

resistance-related protein). The angiogenic factors were reduced. In the third

profile, only five of the resistance factors were increased (MDR1,

thymidylate-synthetase, glutathione-S-transferase-pi,

O6-methylguanine-DNA-methyltransferase, major vault protein/lung

resistance-related protein). Copyright 2002 Cancer Research UK

 

PMID: 12177790 [PubMed - indexed for MEDLINE]

 

 

 

11: J Clin Oncol  2002 Aug 15;20(16):3478-83

 

Neuroprotective effect of reduced glutathione on oxaliplatin-based chemotherapy

in advanced colorectal cancer: a randomized, double-blind, placebo-controlled

trial.

 

Cascinu S, Catalano V, Cordella L, Labianca R, Giordani P, Baldelli AM, Beretta

GD, Ubiali E, Catalano G.

 

Department of Medical Oncology, Azienda Ospedaliera-Universitaria di Parma, via

Gramsci 14, 43100 Parma, Italy. cascinu@yahoo.com

 

PURPOSE: We performed a randomized, double-blind, placebo-controlled trial to

assess the efficacy of glutathione (GSH) in the prevention of

oxaliplatin-induced neurotoxicity. PATIENTS AND METHODS: Fifty-two patients

treated with a bimonthly oxaliplatin-based regimen were randomized to receive

GSH (1,500 mg/m(2) over a 15-minute infusion period before oxaliplatin) or

normal saline solution. Clinical neurologic evaluation and electrophysiologic

investigations were performed at baseline and after four (oxaliplatin dose, 400

mg/m(2)), eight (oxaliplatin dose, 800 mg/m(2)), and 12 (oxaliplatin dose, 1,200

mg/m(2)) cycles of treatment. RESULTS: At the fourth cycle, seven patients

showed clinically evident neuropathy in the GSH arm, whereas 11 patients in the

placebo arm did. After the eighth cycle, nine of 21 assessable patients in the

GSH arm suffered from neurotoxicity compared with 15 of 19 in the placebo arm.

With regard to grade 2 to 4 National Cancer Institute common toxicity criteria,

11 patients experienced neuropathy in the placebo arm compared with only two

patients in the GSH arm (P =.003). After 12 cycles, grade 2 to 4 neurotoxicity

was observed in three patients in the GSH arm and in eight patients in the

placebo arm (P =.004). The neurophysiologic investigations (sural sensory nerve

conduction) showed a statistically significant reduction of the values in the

placebo arm but not in the GSH arm. The response rate was 26.9% in the GSH arm

and 23.1% in the placebo arm, showing no reduction in activity of oxaliplatin.

CONCLUSION: This study provides evidence that GSH is a promising drug for the

prevention of oxaliplatin-induced neuropathy, and that it does not reduce the

clinical activity of oxaliplatin.

 

Publication Types:

Clinical Trial

Randomized Controlled Trial

 

PMID: 12177109 [PubMed - indexed for MEDLINE]

 

 

 

12: Curr Top Med Chem  2002 Jul;2(11):1239-59

 

Enzymes of the trypanothione metabolism as targets for antitrypanosomal drug

development.

 

Schmidt A, Krauth-Siegel RL.

 

Biochemie-Zentrum Heidelberg, Ruprecht-Karls-Universitat, Im Neuenheimer Feld

328, Heidelberg, 69120, Germany. krauth-siegel@urz.uni-heidelberg.de

 

Trypanosomatids are the causative agents of African sleeping sickness, Chagas'

disease and the three forms of leihmaniasis. New drugs against these parasitic

protozoa are urgently needed since the currently available chemotherapy is not

at all satisfying. One promising approach towards the development of new drugs

is based on the design of specific enzyme inhibitors. Trypanosomes and

leishmania possess a unique thiol metabolism in which the ubiquitous

glutathione/glutathione reductase system is replaced by trypanothione and

trypanothione reductase. The dithiol trypanothione is the key molecule for the

synthesis of DNA precursors, the homeostasis of ascorbate, the detoxification of

hydroperoxides, and the sequestration/export of thiol conjugates. Synthesis and

reduction of trypanothione are essential for the maintenance of a reducing

intracellular milieu which renders the respective enzymes attractive drug target

molecules. Here we present the current state of knowledge of the thiol

metabolism of trypanosomatids, comprising the trypanothione/tryparedoxin,

thioredoxin, and ovothiol systems of the parasites. The most effective

inhibitors of the enzymes known to date, their mode of action, and the

(dis)advantages of different types of inhibitors as potential drug candidates

will be discussed.

 

PMID: 12171583 [PubMed - in process]

 

 

 

13: Clin Exp Med  2002 Jul;2(2):99-103

 

Modulation of intracellular glutathione concentration alters dehydropyrimidine

dehydrogenase activity in peripheral blood mononuclear cells.

 

Iwata S, Takabayashi A, Yamaoka Y.

 

Department of Gastroenterological Surgery and Oncology, Kitano Hospital, The

Tazuke Kohukai Medical Research Institute, Osaka, Japan.

iwata@hosp.city.kyoto.jp

 

Dehydropyrimidine dehydrogenase (DPD) is the initial key enzyme in the

regulation of 5-fluorouracil catabolism and thus controls availability of

5-fluorouracil for anabolism. Modulation of DPD activity may increase the

antitumor effect and avoid toxic side effects in 5-fluo-rouracil-based

chemotherapy. We measured DPD activity in peripheral blood mononuclear cells

from cancer patients and simultaneously monitored intracellular glutathione

(GSH) and plasma GSH l