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Query: UMLS:C1140680 (
ovarian cancer
)
28,141
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Cycloplatam is a novel platinum compound which has shown anti-tumour activity in murine tumour models. In this study, cycloplatam was found to have anti-tumour activity in vitro and in vivo in human tumour models. In 15 cell lines (mainly ovarian), cycloplatam showed similar cytotoxicity as cisplatin, using the sulphorhodamine B assay. Determination of the resistance factor (IC50 of cisplatin-resistant divided by IC50 of parental cell line) clearly showed lower values for cycloplatam than for cisplatin. In the parental ovarian cell line
CH1
and the cisplatin-resistant
CH1
cisR model, we observed no cross-resistance of cycloplatam and cisplatin. The in vitro anti-tumour activity was confirmed in human tumour xenografts using the clonogenic assay. Mean IC70 values of cycloplatam were 0.54 microgram/ml (1.25 microM) and of cisplatin 0.42 microgram/ml (1.4 microM), respectively. In the murine subcutaneously implanted ADJ/PC6 plasmacytoma in vivo cycloplatam showed less activity than cisplatin, with a 2-fold smaller therapeutic index than cisplatin. In
ovarian cancer
xenografts cycloplatam was less active than cisplatin. However, anti-tumour activity of cycloplatam in lung cancer xenografts was quite different from cisplatin. In LXFS 538, a model moderately sensitive to cisplatin, a partial remission was observed, but in LXFL 529, a cisplatin-sensitive model, cycloplatam was inactive, cycloplatam thus demonstrating a different spectrum of anti-tumour activity. Based on these results, further preclinical investigations with other tumours, such as cisplatin-sensitive and -resistant gastric cancer models, are warranted with cycloplatam.
...
PMID:Cycloplatam: a novel platinum compound exhibiting a different spectrum of anti-tumour activity to cisplatin. 778 2
In spite of clinical activity in heavily-pretreated
ovarian cancer
, the antitumour s-triazine trimelamol [TM; tris(hydroxymethyl)-tris(methyl)melamine] had to be withdrawn from further clinical studies due to formulation difficulties related to instability. A synthetic programme has produced tris(hydroxymethyl) analogues containing electron-withdrawing groups in place of methyl-triscyanomethyl CB 7669, tristrifluoroethyl CB 7639, CB 7529 and trispropargyl CB 7547, all showing markedly superior stability to TM. Chemosensitivity testing of analogues (MTT assay, continuous exposure) using a panel of rodent and human cell lines showed activity close to that of TM, e.g. for the
CH1
human
ovarian cancer
cell line. IC50 values were TM 23.4 microM, CB 7639 30.5 microM, CB 7529 29.5 microM, CB 7547 28.5 microM and CB 7669 27.3 microM. CB 7669 and CB 7639 required prolonged exposure (> 12 h) in order to exhibit equivalent cytotoxicity to a 2-h exposure to TM. Thus, rather than administration as a single daily dose, the stable analogues may be more suited to prolonged infusion, which was suggested as being a more beneficial regimen in clinical trials with TM. In line with clinical observations indicating the efficacy of TM in platinum-refractory
ovarian cancer
, we saw no significant cross-resistance to TM or CB 7529 in a range of platinum-sensitive and acquired-resistant cell line pairs or in an alkylating-agent resistant cell line, despite TM's ability to crosslink DNA. Data obtained using cell lines with acquired resistance to TM, CB 7669 and formaldehyde (released in the breakdown of TM) suggest a pivotal role for formaldehyde and a more minor role for alkylating activity in the mechanism of action of the N-(hydroxymethyl)melamines in vitro. Further clinical trials of these compounds are eagerly awaited, and their usefulness as second-line chemotherapy for heavily pretreated
ovarian cancer
deserves further investigation.
...
PMID:Stable analogues of the antitumour agent trimelamol retain in vitro cytotoxicity in drug-sensitive and resistant rodent and human cell lines. 788 Jun 14
A proportion of ovarian carcinomas markedly overexpress the proto-oncogene c-met, which encodes the receptor for hepatocyte growth factor (HGF). HGF may either stimulate or inhibit the multiplication of its target cells, and may also promote motogenesis and morphogenesis. In this study, we established that the ovarian carcinoma-derived cell-line SK-OV-3 expressed about 20-fold higher levels of c-met protein than are expressed by a second line,
CH1
. This enabled us to test functional consequences of high-level expression of c-met in ovarian carcinoma cells. The addition of HGF to attached cultures of SK-OV-3 cells caused a change to a motile phenotype, that was evident after 4-6 hr and affected essentially all of the cells by 24 hr. When HGF was placed in the lower compartment of a migration chamber, it induced a 17-fold increase in the migration of SK-OV-3 cells to the lower surface of the filter. Finally, HGF stimulated the incorporation of [3H]-thymidine by cultures of SK-OV-3 cells incubated in medium containing either low (0.2%) or full (10%) FCS. None of these responses were obtained when HGF was added to
CH1
cells. We conclude that high levels of c-met expression in
ovarian cancer
cells may lead to a range of responses to HGF that would promote tumour growth and dissemination.
...
PMID:Hepatocyte growth factor stimulates motility, chemotaxis and mitogenesis in ovarian carcinoma cells expressing high levels of c-met. 933 23
The P53 gene is frequently mutated in late stage
ovarian cancer
and has been proposed as a determinant of radiation and chemosensitivity. We have therefore determined the p53 functional status, P53 sequence, radiation sensitivity and cytotoxicity of cisplatin and the novel platinum analogue, AMD473, in a panel of 6 human
ovarian cancer
cell lines. Constitutive p53 protein levels were low in A2780,
CH1
, LK1, LK2 and PA1 but were markedly induced following irradiation. In OV1P, constitutive p53 protein was readily detectable and levels were induced slightly following irradiation. p21WAF1/CIP1 and MDM-2 mRNA were constitutively expressed in all the cell lines and expression was induced markedly following irradiation. There was marked radiation induced G1/S arrest in A2780 but only partial arrests in
CH1
, LK1, LK2, PA1 and OV1P lines. No mutations were found in A2780,
CH1
, LK1, LK2 and PA1 cells by single-strand conformational polymorphism (SSCP) analysis but a heterozygous point mutation was found in exon 5 of OV1P. All the cell lines were radiation sensitive and also relatively sensitive to cisplatin; however, OV1P was the most resistant being consistent with its heterozygous P53 status. AMD473 was less potent than cisplatin but a similar pattern of drug sensitivity was observed with the exception of LK2, which was resistant.
CH1
, LK1, LK2 and PA1 all expressed BCL-2 protein but there was no expression in A2780 and OV1P. Our results suggest an overall association between wild type P53 and radiation and platinum drug sensitivity in these
ovarian cancer
cell lines.
...
PMID:Characterisation of the p53 status, BCL-2 expression and radiation and platinum drug sensitivity of a panel of human ovarian cancer cell lines. 971 63
A novel sequence-selective pyrrolobenzodiazepine (PBD) dimer 5 (SJG-136) has been developed that comprises two C2-exo-methylene-substituted DC-81 (3) subunits tethered through their C8 positions via an inert propanedioxy linker. This symmetric molecule is a highly efficient minor groove interstrand DNA cross-linking agent (XL(50) = 0.045 microM) that is 440-fold more potent than melphalan. Thermal denaturation studies show that, after 18 h incubation with calf thymus DNA at a 5:1 DNA/ligand ratio, it increases the T(m) value by 33.6 degrees C, the highest value so far recorded in this assay. The analogous dimer 4 (DSB-120) that lacks substitution/unsaturation at the C2 position elevates melting by only 15.1 degrees C under the same conditions, illustrating the effect of introducing C2-exo-unsaturation which serves to flatten the C-rings and achieve a superior isohelical fit within the DNA minor groove. This behavior is supported by molecular modeling studies which indicate that (i) the PBD units are covalently bonded to guanines on opposite strands to form a cross-link, (ii) 5 has a greater binding energy compared to 4, and (iii) 4 and 5 have equivalent binding sites that span six base pairs. Dimer 5 is significantly more cytotoxic than 4 in a number of human
ovarian cancer
cell lines (e.g., IC(50) values of 0.0225 nM vs 7.2 nM, respectively, in A2780 cells). Furthermore, it retains full potency in the cisplatin-resistant cell line A2780cisR (0.024 nM), whereas 4 loses activity (0.21 microM) with a resistance factor of 29.2. This may be due to a lower level of inactivation of 5 by intracellular thiol-containing molecules. A dilactam analogue (21) of 5 that lacks the electrophilic N10-C11/N10'-C11' imine moieties has also been synthesized and evaluated. Although unable to interact covalently with DNA, 21 still stabilizes the helix (Delta T(m) = 0.78 degrees C) and has significant cytotoxicity in some cell lines (i.e., IC(50) = 0.57 microM in
CH1
cells), presumably exerting its effect through noncovalent interaction with DNA.
...
PMID:Design, synthesis, and evaluation of a novel pyrrolobenzodiazepine DNA-interactive agent with highly efficient cross-linking ability and potent cytotoxicity. 1126 84
The effect of overexpressing the antiapoptotic protein BclXL in a human ovarian carcinoma cell line has been investigated in terms of sensitivity to the 2 major drugs used to treat this disease, paclitaxel and cisplatin. Stable transfection of BclXL into
CH1
cells, which are relatively sensitive to cisplatin, resulted in around 2.7-fold higher expression in comparison with empty vector controls. However, this level of overexpression did not result in significant resistance in vitro to paclitaxel or cisplatin at the 50% inhibition level, using either short-term (4-day) growth inhibition or longer term colony-forming assays. By contrast, parallel subcutaneous xenograft models of these isogenic ovarian carcinoma cells in vivo, differing only in BclXL status, showed that this low-level BclXL overexpression conferred significant resistance to both paclitaxel and cisplatin in comparison with parent, nontransfected tumours. Whereas parent non-BclXL transfected tumours were highly responsive, with the disappearance of tumours for at least 50 days post treatment, tumours overexpressing BclXL grew back after 30 and 20 days after treatment with paclitaxel and cisplatin, respectively. These differences in responsiveness to paclitaxel in vivo were not attributable to any significant changes in the delivery of drug to the tumour. These data suggest that the responsiveness of
ovarian cancer
to paclitaxel and cisplatin in vivo, and therefore perhaps clinically, is influenced by levels of the antiapoptotic protein BclXL. Such effects may be missed in vitro when using short-term growth inhibition or clonogenic assays.
...
PMID:Overexpression of BclXL in a human ovarian carcinoma cell line: paradoxic effects on chemosensitivity in vitro versus in vivo. 1185 68
A series of osteotropic (bone-seeking) [(bis(phosphonomethyl)amino-kappaN)acetato-kappaO(2-)]platinum(II) complexes attached to diammine, ethane-1,2-diamine, cis-R,S-cyclohexane-1,2-diamine, trans-S,S-cyclohexane-1,2-diamine, or trans-R,R-cyclohexane-1,2-diamine has been synthesized in accord with the concept of drug targeting and characterized by elemental analysis, (1)H, (13)C, and (31)P NMR spectroscopy. The in vitro antitumor activity in
ovarian cancer
cells (
CH1
) has been determined by means of the MTT assay. In this cisplatin-sensitive cell line the complexes containing cyclohexane-1,2-diamine (chxn) displayed a high activity in comparison to the diammine and ethane-1,2-diamine counterparts. In agreement with structure-activity relationships of other chxn-containing platinum(II) complexes both [(bis(phosphonomethyl)amino-kappaN)acetato-kappaO(2-)](trans-cyclohexane-1,2-diamine)platinum(II) complexes show superior potency than the corresponding cis-congener whereas the trans-R,R isomer displays the highest activity. Within the series of complexes under investigation, potency decreases depending on the coordinated amine ligand in the following order: trans-R,R-chxn > trans-S,S-chxn > NH(3) > or = cis-R,S-chxn > en.
...
PMID:Synthesis, characterization, and in vitro antitumor activity of osteotropic diam(m)ineplatinum(II) complexes bearing a N,N-bis(phosphonomethyl)glycine ligand. 1458 45
Oxaliplatin, (trans-R,R-cyclohexane-1,2-diamine)oxalatoplatinum(II), has recently been approved for combination chemotherapy of metastatic colorectal cancer. Oxaliplatin is significantly more active than its trans-S,S isomer and the mixture of both enantiomers. New oxaliplatin analogues, (SP-4-3)-(4-methyl-trans-cyclohexane-1,2-diamine)oxalatoplatinum(II) and (SP-4-3)-(4-ethyl-trans-cyclohexane-1,2-diamine)oxalatoplatinum(II), have been synthesized, and their cytotoxicity has been tested in comparison to oxaliplatin, its corresponding trans-S,S isomer, and the mixture of both enantiomers. In comparison to oxaliplatin, even the trans-R,R/trans-S,S mixture of the 4-methyl and 4-ethyl substituted oxaliplatin analogues have shown an equivalent cytotoxicity in
ovarian cancer
cells (
CH1
) and superior antiproliferative properties in colon cancer cells (SW480) in the case of a predominantly equatorial position of the substituent at position 4 of the trans-cyclohexane-1,2-diamine ligand, whereas an axial substitution results in decreased cytotoxic potency.
...
PMID:Synthesis, crystal structure and cytotoxicity of new oxaliplatin analogues indicating that improvement of anticancer activity is still possible. 1527 4
Antineoplastic ruthenium(III) complexes are generally regarded as prodrugs, being activated by reduction. Within a homologous series of ruthenium(III) complexes, cytotoxic potency is therefore expected to increase with increasing ease of reduction. Complexes of the general formula [Ru(III)Cl((6-n))(ind)n](3-n)- (n = 0-4; ind = indazole; counterions = Hind(+) or Cl(-)) and the compound trans-[Ru(II)Cl(2)(ind)(4)] have been prepared and characterized electrochemically. Lever's parametrization method predicts that a higher indazole-to-chloride ratio results in a higher reduction potential, which is confirmed by cyclic voltammetry. In vitro antitumor potencies of these complexes in colon cancer cells (SW480) and
ovarian cancer
cells (
CH1
) vary by more than 2 orders of magnitude and increase in the following rank order: [Ru(III)Cl(6)](3-) < [Ru(III)Cl(4)(ind)(2)](-) < [Ru(III)Cl(5)(ind)](2-) << [Ru(III)Cl(3)(ind)(3)] < [Ru(III)Cl(2)(ind)(4)](+) approximately [Ru(II)Cl(2)(ind)(4)]. Thus, the observed differences in potency correlate with reduction potentials largely, though not perfectly, pointing to the influence of additional factors. Differences in the cellular uptake (probably resulting from different lipophilicity) contribute to this correlation but cannot solely account for it.
...
PMID:Redox-active antineoplastic ruthenium complexes with indazole: correlation of in vitro potency and reduction potential. 1582 21
Four new trans-planaramineplatinum(II) complexes, three of the form: trans-PtCl2L2, code named
CH1
, CH2 and CH4 where L = 3-hydroxypyridine, 4-hydroxypyridine and imidazo[1,2-alpha]pyridine, respectively, and one of the form: PtClL3, code named CH3 where L = 3-hydroxypyridine, have been prepared and characterized by elemental analyses and IR, Raman, mass and 1H NMR spectral studies. The interactions of the compounds with salmon sperm and pBR322 plasmid DNAs have been investigated and their activity against human
ovarian cancer
cell lines: A2780, A2780cisR and A2780ZD0473R have also been determined. The compounds are believed to form mainly monofunctional N7(G) and bifunctional intrastrand N7(G)N7(G) adducts with DNA, causing a local distortion of DNA as a result of which gel mobility of the DNA changes. The compound containing three planaramine ligands per molecule (CH3) is found to be less reactive than the compounds containing two planaramine ligands per molecule (
CH1
, CH2 and CH4), which in turn are less reactive than compounds containing one of the same planaramine ligands per molecule. The decrease in reactivity is reflected in lower molar conductivity values (indicating lower degree of dissociation), less pronounced changes caused to DNA conformation (indicating decreased level of platinum-DNA binding) and lower activity. The decreased reactivity of the compounds is due to a greater steric crowding produced by the bulky planaramine ligands. Changes in DNA conformation are also found to be a function of the actual nature of the planaramine ligand. The results illustrate structure-activity relationship.
...
PMID:Synthesis, characterization and binding with DNA of four planaramineplatinum(II) complexes of the forms: trans-PtL2Cl2 and [PtL3Cl]Cl, where L = 3-hydroxypyridine, 4-hydroxypyridine and imidazo(1,2-alpha)pyridine. 1583 33
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