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J P Moulinoux

Publications and source records attributed to J P Moulinoux.

At least 19 recordsLinked to original sources
PubMed2001

N-Benzylpolyamines as vectors of boron and fluorine for cancer therapy and imaging: synthesis and biological evaluation.

Cancer cells have high-affinity polyamine uptake systems with a low stringency for structural features. Putrescine, spermidine, and spermine have, therefore, been considered as potential vectors for the selective accumulation in tumors of therapeutically or diagnostically useful structures and elements. We envisaged N-benzyl derivatives of the polyamines as vectors of (10)B and (18)F for boron neutron capture therapy (BNCT) and tumor imaging by positron emission tomography (PET), respectively. In the present work, the synthesis, transport characteristics, DNA-binding properties, and cytotoxicity of several N-benzyl derivatives of putrescine and spermidine are described. The fluorinated spermidine derivative N-(3-[(4-aminobutyl)amino]propyl)[(4-fluorophenyl)methyl]amine (N(1)-4-Fbz-spd) may be useful for PET because of its high accumulation in cancer cells via the polyamine transport system. Among the boron-containing benzyl polyamines, N-(4-aminobutyl)([4-(dihydroxyboryl)phenyl]methyl)amine (4-Bbz-put) and N-(3-[(4-aminobutyl)amino]propyl)([4-(dihydroxyboryl)phenyl]methyl)amine (N(1)-4-Bbz-spd) should be suitable for BNCT, because their accumulation in B16 melanoma cells was more efficient than that of borocaptate and borophenylalanine, two reference compounds used in BNCT.

Animals↗
PubMed2001

Clinical significance of cell proliferation, microvessel density, and CD44 adhesion molecule expression in renal cell carcinoma.

Renal cell carcinoma (RCC) is known to have a wide variation in clinical outcome despite the use of conventional prognostic factors, such as staging or grading. A better knowledge of the biologic aggressiveness of RCC could facilitate the selection of patients at high risk of tumor progression. The aim of this study was to determine if use of measurements of vascular density, cell proliferation, and cell adhesion could better predict the biologic behavior of RCC. We immunohistochemically analyzed CD34, Ki-67, and CD44H expression on formalin-fixed, paraffin-embedded tissues from 73 RCCs for quantifying microvessel density (MVD), Ki-67 labeling index (LI), and CD44H LI, respectively. Univariate cancer-specific survival analysis showed that tumor stage (P < .01), tumor size (P < .001), nuclear grade (P < .01), metastasis (P < .001), MVD (P < .03), Ki-67 LI (P < .001), and CD44H LI (P < .0001) were predictors of tumor-related death. There was a statistical correlation between CD44H LI and both Ki-67 LI (r' = .3) and MVD (r' = -44). Ki-67 LI (P < .04) and CD44H LI (P < .02), as well as metastasis (P < .008), emerged as independent predictors of cancer-specific survival in multivariate analysis in patients with metastases (P < .04 and P < .02, respectively) and in patients without metastases (P < .006 and P < .00001, respectively). Our study suggests that vascular density, cell proliferation, and cell adhesion represent a complex tumor-host interaction that may favor progression of RCC. Cell proliferation and CD44H expression appear to be powerful markers to identify patients with an adverse prognosis.

Adult↗
PubMed2000

Polyamines are unevenly distributed within the rat and rabbit kidney.

Aliphatic polyamines have generally been measured on the whole kidney. Since the kidney is composed of a variety of cells, whole organ data are of limited value for the interpretation of the functions of the polyamines. The aim of this study was to establish the distribution pattern of putrescine, spermidine and spermine within the kidneys of male and female rats and rabbits. It is shown that the polyamines are unevenly distributed along the cortico-papillary axis. Each amine exhibited its own distinct distribution pattern. The polyamines are predominantly located in the cortex. Putrescine levels increased gradually from the cortex to the papillary tip in rabbits, whereas, in rats, fluctuations in putrescine level were marked. In the six zones of the rabbit kidney studied, spermidine and spermine concentrations were markedly higher in females than in males. This difference was less marked in rats.

Animals↗
PubMed2000

Value of immunohistochemical Ki-67 and p53 determinations as predictive factors of outcome in renal cell carcinoma.

OBJECTIVES: Nuclear grade and tumor stage are important prognostic factors in renal cell carcinoma, but tumors of similar stage and grade can exhibit a wide variation in biologic behavior and clinical outcome. In this retrospective study, we evaluated the immunologic markers, Ki-67 (MIB1) and p53, in 73 cases of conventional (clear cell) renal cell carcinoma and compared these markers with the accepted prognostic features of grade, stage, and tumor size in predicting outcome. METHODS: Specimens of 73 renal cell carcinomas of different nuclear grade (20 Furhman I/II, 32 Fuhrman III, and 21 Fuhrman IV) and different stage (10 pT1, 23 pT2, 36 pT3, and 4 pT4) were immunostained with monoclonal antibodies against Ki-67 and p53. RESULTS: Univariate statistical analysis showed that tumor size (P <0. 001), nuclear grade (P <0.01), tumor stage (P <0.01), Ki-67 index (P <0.001), and p53 immunostaining (P <0.03) correlated significantly with a poor prognosis. A Ki-67 index of 20% was a powerful predictor of survival in all patients (P <0.00001), with strong predictive values. On multivariate analysis, the Ki-67 index and metastases were significant independent prognostic factors (P <0.02 and <0.01, respectively). CONCLUSIONS: Ki-67 immunostaining appeared to be an additional prognostic indicator of biologic aggressiveness in renal cell carcinoma. Immunohistochemical assessment of tumor antigens could be used to identify patients at high risk of tumor progression in addition to conventional prognostic factors.

Adult↗
PubMed2000

Polyamine profiles in tumor, normal tissue of the homologous breast, blood, and urine of breast cancer sufferers.

Polyamines are involved in the development of breast cancer. We assayed polyamines in erythrocytes, urines, and breast tissues (tumor tissue and histologically normal breast tissue close to the tumor) of patients with invasive breast cancer (n = 174) and benign breast disease (n = 71, used as controls). Polyamine levels in red blood cells and urine were similar to the polyamine concentrations found in healthy subjects, and thus cannot be used as diagnostic markers of breast cancer. In cancer tissue, polyamines were significantly increased in comparison with the polyamine concentrations in controls, and were correlated to the tumor aggressiveness as evaluated by histological grade and Ki-67 proliferative index. On the other hand, correlation was found between polyamine levels in the tumor and the status of the hormone receptors. In the mammary tissue close to the cancer, polyamines dramatically decreased in comparison with the polyamine levels of tissue samples removed around the histologically proven benign tumors. The changes of the polyamine concentrations in the histologically normal breast tissue in the vicinity of the cancer could play a role in the cancer development and need further studies, especially if polyamines are considered as a potential therapeutic target in breast cancer.

Adenocarcinoma↗
PubMed1999

Polyamine deprivation alters formalin-induced hyperalgesia and decreases morphine efficacy.

Although the exact functions of polyamines in the nervous system remain still unclear, they are thought to have a physiological role in intracellular signal processing and neurotransmission. Polyamine deprivation which consists in the reduction of both the endogenous and exogenous sources of polyamines is a promising treatment for cancer. In a previous study we have shown that this treatment provokes an analgesic effect in rats submitted to brief phasic nociceptive tests. The present study examined the effect of polyamine deprivation on pain-related behaviors and spinal c-fos expression evoked in the formalin test presumed to better reflect clinical pain, using morphine as analgesia control. Polyamine deprivation per se altered the characteristic pain-related behaviors, reducing the interphase depression of pain, without inducing changes in the spinal Fos staining. In addition this treatment prevented the antinociceptive effect of morphine both on behavioral responses and on spinal c-fos expression. In polyamine-deprived rats, despite morphine injection, nociceptive scores remained dramatically high during the intermediate and the late phases of the response and the number of Fos immunoreactive neurons remained largely higher in deeper layers than in morphine control rats. Altogether these data support a modulatory role of polyamines both on the neuronal circuitry mediating sensory information, and on mechanisms underlying morphine analgesia.

Analgesics, Opioid↗
PubMed1999

Molecular analysis of the combining site of a monoclonal antibody against spermine.

The structural basis of the binding of the polyamine spermine to the monoclonal antibody SPM8-2 was studied using computer modelling, ELISA methods and chemical modifications of the binding site residues. Paratope modelling showed that the antibody combining site forms a highly negatively charged cavity mainly shaped by aspartic acid and tyrosine residues which contact the tetra-positively charged spermine molecule by electrostatic interactions and hydrogen bondings. The importance of the electrostatic environment for spermine binding to SPM8-2 is emphasised by the strong dependency on pH and ionic strength. Specific chemical modifications of carboxylate groups and tyrosine residues of the antibody adsorbed to microtiter plates resulted in decreased binding of the N1-biotin-spermine conjugate used to monitor the activity of the antibody. These observations are consistent with a key role of aspartate and tyrosine residues in complex formation with spermine. These studies, important to our understanding of antibody-hapten specificity, may also shed light on important motifs responsible for protein-polyamine interactions.

Amino Acid Sequence↗
PubMed1999

Induction of Fos protein expression in spinal cord neurons of tumour-bearing rats.

The absence of discernible abnormal symptoms such as pain, often leading to delayed diagnosis in cancer patients, may be indicative of a dysregulation in sensory transmission between the tumour and the central nervous system. We explored expression of Fos protein in spinal cord neurons in rats, during the development of the MAT-LyLu prostatic adenocarcinoma grafted on the hind limb. The tumour triggered the densest Fos labelling in the L3-L5 lumbar segments, ipsilateral to the grafted limb. The labelling, detected at day 5, increased until day 10 and dropped off thereafter. The ventral horn (except lamina IX) was the most densely labelled region. Histological examination of the grafted limbs demonstrated that no inflammatory reaction accompanied the tumour growth. Rats exhibited no behavioural alterations either spontaneous or induced by handling. These results demonstrate that signals are sent to the central nervous system by the peripheral tumour. Considering both the behavioural and histological observations, it is unlikely that spinal activity reflects a painful state. The nature of these signals, inefficient to trigger the appropriate reaction of the organism against the tumour, remain to be determined with regard to the pharmacologically active compounds synthesized and released by the tumour cells.

Adenocarcinoma↗
PubMed1998

Polyamine sulfonamides with NMDA antagonist properties are potent calmodulin antagonists and cytotoxic agents.

N1-Dansylspermine and related sulfonamides of the natural polyamines are very potent blockers of NMDA-type glutamate receptors. They exhibit pharmacological properties which were not predicted from the constituents of the conjugates. Cytotoxicity and calmodulin antagonism of N1-dansylspermine were especially impressive. Calmodulin antagonism implies that N1-dansylspermine prevents induction of ornithine decarboxylase and inhibits its own active uptake via the polyamine transport system. Structure-activity considerations demonstrated that an aromatic character of the substituent is not required; amide bond formation with an aliphatic sulfonic acid is sufficient to transform spermine into a highly toxic calmodulin antagonist. Cytotoxicity and calmodulin antagonism are properties which are intrinsic to spermine, but they are observed only at very high concentrations. Amide bond formation at N1 with a lipophilic residue appears to 'amplify' these normally latent properties. The use of polyamine conjugates structurally related to the amides described in this work for targeting tumours may be marred by their calmodulin antagonism.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1997

Tumour growth modifies intravascular polyamine transport by plasma lipoproteins in the mouse.

Polyamines are polycationic compounds which are implicated in cell division and tumor growth. We have evaluated the potential role of plasma lipoproteins in the transport of major polyamines, spermine, spermidine and putrescine, and the effect of tumor growth on such transport. Plasmas of healthy male BL6/DBA2 mice and of mice bearing Lewis lung carcinoma (3LL) were fractionated by isopycnic density gradient ultracentrifugation, and polyamine content determined in lipoprotein fractions. Spermidine was the most abundant polyamine in the lipoproteins of both control and tumor-bearing mice and was principally associated with HDL (d: 1.046-1.136 g/ml); approx. 40% of total plasma polyamines was lipoprotein-associated in control mice and 60% in cancerous mice. Only minor amounts were transported by LDL (< 10% of total lipoprotein-associated polyamines), while VLDL were devoid of these substances. Marked elevations of circulating levels of LDL were found in 3LL grafted mice: in these particles however, the contents of spermidine and spermine were significantly reduced. A preferential uptake of polyamines by red blood cells could in part explain this marked reduction of LDL polyamine content, but the consequence of this reduction on the net electrical charge and biochemical function of LDL remains unknown. Elevations of plasma LDL and HDL levels in 3LL-grafted mice underlie the finding that only minor modification was detected in the putrescine content of these particles. However, it is evident that elevated total amounts of putrescine were present in the plasma of such animals. Finally, the density profile of polyamines was modified in cancerous mice in which a shift to transport in lighter apo.AI-containing HDL particles was observed for spermidine; an even more marked shift was found for spermine. In conclusion, our data demonstrate that HDL particles constitute the major plasma vehicle for polyamine transport in both control and in tumor-bearing mice.

Animals↗
PubMed1997

Flow cytometric analysis of in vivo polyamine deprivation in Lewis lung carcinoma (3LL) cells using the monoclonal antibody SPM8-2.

It has previously been shown that the monoclonal antibody SPM8-2 recognizes free spermine and spermidine as well as polyamines bound by an amide bond. In the present work it is demonstrated that this antibody also interacts with spermidine, spermine, and to a lesser extent N1- and N8-acetyl spermidine in an ELISA test where the polyamines are bound by reaction with formaldehyde. 3LL Lewis lung carcinoma cells from tumor-grafted mice were labeled with fluorescein-conjugated monoclonal antibody SPM8-2 and analyzed by flow cytometry. Both viable cells and formaldehyde-fixed and subsequently permeabilized cells showed fluorescent staining. However, most polyamines present in the cells are not directly available for antibody binding. Treatment of fixed cells with DNase or RNase greatly increased fluorescent staining, suggesting that some polyamines are co-localized with DNA and RNA. Antibody labeling of the cells was prevented by addition of free spermine. 3LL cells from tumors of mice treated by a polyamine depleting regimen had decreased intracellular spermidine levels and bound less antibody when compared to untreated controls. After digestion with RNase, the cells from treated mice bound considerably less fluorescent antibody than tumor cells from untreated mice, while their RNA content was similar. In contrast, fluorescent staining after DNase digestion was only slightly affected by the treatment with a polyamine depleting regimen. This suggests that the pools of polyamines which are co-localized with RNA are depleted more readily than those associated with DNA. Since only a small proportion of the intracellular polyamines is accessible to the bulky antibodies, treatment with hydrolytic enzymes (DNase, RNase) is necessary to reveal specific compartments of the polyamines and to demonstrate qualitative and semi-quantitative differences of their distribution within cells.

Animals↗
PubMed1997

Biochemical and cellular effects of roscovitine, a potent and selective inhibitor of the cyclin-dependent kinases cdc2, cdk2 and cdk5.

Cyclin-dependent kinases (cdk) play an essential role in the intracellular control of the cell division cycle (cdc). These kinases and their regulators are frequently deregulated in human tumours. Enzymatic screening has recently led to the discovery of specific inhibitors of cyclin-dependent kinases, such as butyrolactone I, flavopiridol and the purine olomoucine. Among a series of C2, N6, N9-substituted adenines tested on purified cdc2/cyclin B, 2-(1-ethyl-2-hydroxyethylamino)-6-benzylamino-9-isopropylpurine (roscovitine) displays high efficiency and high selectivity towards some cyclin-dependent kinases. The kinase specificity of roscovitine was investigated with 25 highly purified kinases (including protein kinase A, G and C isoforms, myosin light-chain kinase, casein kinase 2, insulin receptor tyrosine kinase, c-src, v-abl). Most kinases are not significantly inhibited by roscovitine. cdc2/cyclin B, cdk2/cyclin A, cdk2/cyclin E and cdk5/p35 only are substantially inhibited (IC50 values of 0.65, 0.7, 0.7 and 0.2 microM, respectively). cdk4/cyclin D1 and cdk6/cyclin D2 are very poorly inhibited by roscovitine (IC50 > 100 microM). Extracellular regulated kinases erk1 and erk2 are inhibited with an IC50 of 34 microM and 14 microM, respectively. Roscovitine reversibly arrests starfish oocytes and sea urchin embryos in late prophase. Roscovitine inhibits in vitro M-phase-promoting factor activity and in vitro DNA synthesis in Xenopus egg extracts. It blocks progesterone-induced oocyte maturation of Xenopus oocytes and in vivo phosphorylation of the elongation factor eEF-1. Roscovitine inhibits the proliferation of mammalian cell lines with an average IC50 of 16 microM. In the presence of roscovitine L1210 cells arrest in G1 and accumulate in G2. In vivo phosphorylation of vimentin on Ser55 by cdc2/cyclin B is inhibited by roscovitine. Through its unique selectivity for some cyclin-dependent kinases, roscovitine provides a useful antimitotic reagent for cell cycle studies and may prove interesting to control cells with deregulated cdc2, cdk2 or cdk5 kinase activities.

Adenosine Triphosphate↗
PubMed1997

Polyamine deprivation prevents the development of tumour-induced immune suppression.

Mice grafted with the 3LL (Lewis lung) carcinoma exhibit immune suppression: spleen cells showed decreased spontaneous interleukin 2 (IL-2) production and T-CD4+ and T-CD8+ lymphocyte populations; in addition the polyamine content in the spleen was increased. By treating the mice with a polyamine-deficient diet containing neomycin, metronidazole and inhibitors of ornithine decarboxylase and polyamine oxydase, tumour growth was reduced and the immune abnormalities were reversed. The spleen cells overproduced IL-2 by reducing exogenous sources of polyamines, but total blockade of all major polyamine sources was necessary to obtain an optimal effect both on IL-2 production and on spleen polyamine content. Irrespective of whether polyamine deprivation was started at an early or at an advanced stage of tumour growth, T-lymphocyte populations were restored to normal values, demonstrating that polyamine deprivation not only prevents tumour-induced immune suppression, but reverses established immunological disorders. In contrast to what was observed regarding IL-2 production by spleen cells and natural killer (NK) cell activity, the polyamine oxidase (PAO) inhibitor did not enhance the number of T lymphocytes. These findings are consistent with a direct effect of the polyamines on immune effector cell metabolism. They suggest an important role of the gastrointestinal polyamines and of PAO activity in the regulation of IL-2 production.

Animals↗
PubMed1997

Erythrocyte spermine levels: a prognostic parameter in childhood common acute lymphoblastic leukemia.

Polyamines have been implicated to play a role in cell proliferation and in cancer development. Ninety percent of the circulating spermidine (Spd) and spermine (Spm) are transported by red blood cells (RBC). RBC Spd and Spm levels were prospectively determined in 63 unselected children with common acute lymphoblastic leukemia. The Spm and Spd levels were not correlated with white blood cell (WBC) count. On the basis of the polyamine levels it was possible to discriminate four groups with P< 10(-3). In C1, C2, C3 and C4 group the Spm level was respectively 90 (39-597), 3.75 (1-7.45), 9.95 (2.9-12.6) and 17(6.3-33.8). The probability of relapse-free survival (RFS) of the 58 children who entered complete remission was 55% +/- 9. For the groups C1 (n = 6), C2 (n = 16), C3 (n = 21) and C4 (n= 15) groups, the RFS was 25% +/- 20, 73% +/- 12, 73% +/- 13 and 32% +/- 13 respectively. For children with Spm levels <13/> or = 13nmol/8 x 10(9) RBC, event-free survival (EFS) was 54% +/- 11/33% +/- 10 and RFS was 64% +/- 12/38% +/- 11 respectively (P < 0.03, P < 0.005). Our clinical study shows clearly that an RBC spermine level could be used as parameter of prognosis at the time of diagnosis, particularly for patients with intermediary WBC count.

Adolescent↗
PubMed1997

Bis(7-amino-4-azaheptyl)dimethylsilane: a new tetramine with polyamine-like features. Effects on cell growth.

Bis(7-amino-4-azaheptyl)dimethylsilane is a new type of aliphatic polycation with structural features resembling those of spermine. The elongation to a seven-membered carbon chain in which the central CH2-group was substituted by (CH3)2Si renders the molecule more lipophilic than spermine. Cells accumulate the compound via the polyamine transport system. Due to suppression of ornithine decarboxylase, de novo putrescine biosynthesis is impaired, and intracellular putrescine and spermidine concentrations are depleted. Depletion of intracellular spermidine together with binding to functionally important polyamine binding sites are considered the main features of the compound which cause cytostatic, and at high concentrations, cytotoxic effects.

Animals↗
PubMed1997

Dimethylsilane polyamines: cytostatic compounds with potentials as anticancer drugs.

Several dimethylsilane tetramines [homologs of spermine with an Si(CH3)2 group in the central carbon chain], a carbon analog of the dimethylsilane tetramines [containing C(CH3)2 instead of Si(CH3)2] and a dimethylsilane hexamine were studied with regard to their cytotoxic activity and their ability to interact with double-stranded DNA. All polyamine analogs exerted cytostatic effects to several cell lines at micromolar concentrations. Their ability to condense DNA was comparable to and their ability to displace ethidium bromide from binding to DNA was superior to that of spermine. Their cytostatic effect was not correlated with the depletion of cellular spermidine concentrations. It is suggested that the new polyamine analogs act mainly by displacing spermidine from binding sites which are essential for the promotion of cell growth.

Animals↗
PubMed1996

Bis(7-amino-4-azaheptyl)dimethlysilane and bis(7-ethylamino-4-azaheptyl)dimethylsilane: inhibition of tumor cell growth in vitro and in vivo.

Bis(7-amino-4-azaheptyl)dimethylsilane (AzhepSi) and its bis(ethyl) derivative [bis(7-ethylamino-4-azaheptyl)dimethylsilane] (EtAzhepSi) are the first examples of a new type of aliphatic tetramine with a dimethylsilane group incorporated into the central carbon chain. AzhepSi shares certain properties with the natural polyamines, but in contrast with spermidine and spermine it inhibits the growth of L1210 leukemia cells in culture at micromolar concentrations. The bis(ethyl) derivative of AzhepSi was made, in analogy to bis(ethyl) spermine, a polyamine derivative, which gained much attention during the last decade as a potential anticancer drug. Chinese hamster ovary (CHO) cells accumulate the dimethylsilyl tetramines considerably more and are more sensitive to these drugs than are CHO-MG cells, a polyamine uptake-deficient mutant. This and related observations demonstrate that AzhepSi and EtAzhepSi are preferentially taken up by a polyamine transport system. Both tetramines inhibit the growth of a variety of tumor cells at micromolar concentrations. AzhepSi turned out to be either equipotent or more potent, but in no case less potent than EtAzhepSi. When given alone at daily doses of 25 micromol/kg, the compounds did not prolong the survival time of L1210 leukemia mice. However, in combination with 2-(difluoromethyl)ornithine and neomycin, AzhepSi had a significant effect on the life span of the animals. The growth rate of 3LL Lewis lung carcinoma was reduced by both compounds at daily doses of 25 micromol/kg. The observations presented in this work suggest that the dimethylsilyl tetramines are antiproliferative agents in vitro and in vivo. Due to enhanced general toxicity, the introduction of N-ethyl substituents was of no advantage in the case of these polyamine analogues.

Animals↗