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Cancers May 2020(1) Background: Previous findings show that lactam steroidal alkylating esters display improved therapeutic efficacy with reduced toxicity. The aim of this study was to...
(1) Background: Previous findings show that lactam steroidal alkylating esters display improved therapeutic efficacy with reduced toxicity. The aim of this study was to evaluate the anticancer activity of two newly synthesized aza-steroid alkylators (ENGA-L06E and ENGA-L08E) against human ovarian carcinoma cells, and consequently, the dual inhibition of RAS/PI3K/AKT and RAS/RAF/MEK/ERK signaling pathways, both of which are closely associated with ovarian cancer; (2) Methods: The in vitro cytostatic and cytotoxic effects of ENGA-L06E and ENGA-L08E were evaluated in a panel of five human ovarian cancer cell lines, as well as in in vivo studies. ENGA-L06E and ENGA-L08E, in addition to another two aniline-mustard alkylators, POPAM and melphalan (L-PAM), were utilized in order to determine the acute toxicity and antitumor efficacy on two human ovarian xenograft models. Also, in silico studies were performed in order to investigate the dual inhibition of ENGA-L06E and ENGA-L08E on RAS/PI3K/AKT and RAS/RAF/MEK/ERK signaling pathways; (3) Results: Both, in vitro and in vivo studies demonstrated that ENGA-L06E and ENGA-L08E were significantly more effective with a lower toxicity profile in comparison to POPAM and L-PAM alkylators. Moreover, in silico studies demonstrated that the two new aza-steroid alkylators could act as efficient inhibitors of the phosphorylation of AKT and ERK1/2 molecules; and (4) Conclusions: Both ENGA-L06E and ENGA-L08E demonstrated high anticancer activity through the inhibition of the PI3K-AKT and KRAS-ERK signaling pathways against human ovarian carcinoma, and thus constituting strong evidence towards further clinical development.
PubMed: 32429466
DOI: 10.3390/cancers12051263 -
British Journal of Pharmacology Oct 2012Bendamustine with or without rituximab provides an effective and more tolerable alternative to the polytherapy cyclophosphamide-doxorubicin-vincristine-prednisolone...
BACKGROUND AND PURPOSE
Bendamustine with or without rituximab provides an effective and more tolerable alternative to the polytherapy cyclophosphamide-doxorubicin-vincristine-prednisolone (CHOP) in the treatment of haematological tumours and is currently approved for the treatment of many haematological malignancies. Navitoclax (ABT-263) is a potent inhibitor of Bcl-2, Bcl-x(L) and Bcl-w, which has demonstrated efficacy in haematological tumours alone and in combination with other agents. This paper describes the in vivo efficacy of combining either bendamustine or bendamustine plus rituximab (BR) with navitoclax in xenograft models of non-Hodgkin's lymphoma
EXPERIMENTAL APPROACH
Activity was tested in xenograft models of diffuse large B-cell lymphoma (DoHH-2, SuDHL-4), mantle cell lymphoma (Granta 519) and Burkitt's lymphoma (RAMOS). Activity was also monitored in a systemic model of Granta 519.
KEY RESULTS
Navitoclax potentiated bendamustine activity in all cell lines tested. Bendamustine activated p53 in Granta 519 tumours, concurrent with activation of caspase 3. Navitoclax also improved responses to bendamustine-rituximab (BR) in a subset of tumours.
CONCLUSIONS AND IMPLICATIONS
Navitoclax in combination with bendamustine and BR is a viable combination strategy for use in the clinic and demonstrated superior efficacy compared with previously reported data for navitoclax plus CHOP and rituximab-CHOP.
Topics: Aniline Compounds; Animals; Antibodies, Monoclonal, Murine-Derived; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Bendamustine Hydrochloride; Cell Line, Tumor; Humans; Lymphoma, Non-Hodgkin; Mice; Mice, SCID; Nitrogen Mustard Compounds; Proto-Oncogene Proteins c-bcl-2; Rituximab; Sulfonamides; Tumor Burden; Xenograft Model Antitumor Assays
PubMed: 22624727
DOI: 10.1111/j.1476-5381.2012.02048.x -
The Journal of Biological Chemistry Sep 2011The antitumor agent 11β (CAS 865070-37-7), consisting of a DNA-damaging aniline mustard linked to an androgen receptor (AR) ligand, is known to form covalent DNA...
The antitumor agent 11β (CAS 865070-37-7), consisting of a DNA-damaging aniline mustard linked to an androgen receptor (AR) ligand, is known to form covalent DNA adducts and to induce apoptosis potently in AR-positive prostate cancer cells in vitro; it also strongly prevents growth of LNCaP xenografts in mice. The present study describes the unexpectedly strong activity of 11β against the AR-negative HeLa cells, both in cell culture and tumor xenografts, and uncovers a new mechanism of action that likely explains this activity. Cellular fractionation experiments indicated that mitochondria are the major intracellular sink for 11β; flow cytometry studies showed that 11β exposure rapidly induced oxidative stress, mitochondria being an important source of reactive oxygen species (ROS). Additionally, 11β inhibited oxygen consumption both in intact HeLa cells and in isolated mitochondria. Specifically, 11β blocked uncoupled oxygen consumption when mitochondria were incubated with complex I substrates, but it had no effect on oxygen consumption driven by substrates acting downstream of complex I in the mitochondrial electron transport chain. Moreover, 11β enhanced ROS generation in isolated mitochondria, suggesting that complex I inhibition is responsible for ROS production. At the cellular level, the presence of antioxidants (N-acetylcysteine or vitamin E) significantly reduced the toxicity of 11β, implicating ROS production as an important contributor to cytotoxicity. Collectively, our findings establish complex I inhibition and ROS generation as a new mechanism of action for 11β, which supplements conventional DNA adduct formation to promote cancer cell death.
Topics: Acetylcysteine; Aniline Mustard; Animals; Antineoplastic Agents, Alkylating; Cell Death; DNA Adducts; Electron Transport Complex I; Female; Free Radical Scavengers; HeLa Cells; Humans; Male; Mice; Mice, Nude; Mitochondria, Liver; Oxidative Stress; Oxygen Consumption; Rats; Reactive Oxygen Species; Vitamin E; Xenograft Model Antitumor Assays
PubMed: 21832047
DOI: 10.1074/jbc.M111.278390 -
Chemico-biological Interactions Jun 1997The rates of the non-enzymatic conjugation of the substituted aniline mustards, melphalan, chlorambucil and p-(N,N-bis(2-chloroethyl))toluidine with glutathione and...
The rates of the non-enzymatic conjugation of the substituted aniline mustards, melphalan, chlorambucil and p-(N,N-bis(2-chloroethyl))toluidine with glutathione and thiosulfate were determined using nuclear magnetic resonance spectroscopy. Using this method, the disappearance of drug and the formation of both the mono-thioether and bis-thioether conjugates can be monitored directly. For glutathione conjugation, the rate constants for the formation of the first and second aziridinium intermediates were similar. With thiosulfate conjugation, the rate constant for the formation of the first aziridinium intermediate is greater than the rate constant for the formation of the second aziridinium. This demonstrates that the type of nucleophile has a significant influence on the overall alkylating activity of these bifunctional mustards. The bisthioether adduct formed from the reaction between p-(N,N-bis([2-13C]-2-chloroethyl))toluidine and glutathione and thiosulfate can be identified and scrambling of the 13C label in the product provides strong evidence that the alkylation must occur through an aziridinium intermediate.
Topics: Aniline Mustard; Aziridines; Carbon Radioisotopes; Glutathione; Kinetics; Magnetic Resonance Spectroscopy; Melphalan; Thiosulfates
PubMed: 9233374
DOI: 10.1016/s0009-2797(97)00036-7 -
British Journal of Haematology Feb 2005Summary NSC290205 (A) is an hybrid synthetic antineoplastic ester that is a combination of a d-lactam derivative of androsterone and an alkylating derivative of...
Summary NSC290205 (A) is an hybrid synthetic antineoplastic ester that is a combination of a d-lactam derivative of androsterone and an alkylating derivative of N,N-bis(2-chloroethyl)aniline. We tested NSC290205 for synergistic antileukaemic activity with adriamycin (ADR), (i) in vitro against the human lymphoid leukaemia cell lines: CCRF-CEM, MOLT-4, and RPMI-8226, (ii) in vivo against P388 lymphocytic and L1210 lymphoid murine leukaemias (at incipient and advanced phase). Our results indicated significant cytostatic and cytotoxic synergy of NSC290205 and ADR in vitro. We further examined these results in vivo by replacing cyclophosphamide in the standard CHOP (cyclophosphamide, hydroxydaunomycin, Oncovin, prednisone) regimen with NSC290205 (AHOP) and comparing the efficiency of these two regimens in vivo. Although treatment of P388 and L1210 with cyclophosphamide or NSC290205 alone yielded equivalent results, AHOP produced a clear benefit for survival compared with CHOP against advanced leukaemias, confirming the in vitro observations [higher percentage increase in median lifespan of treated animals over the untreated (control): 188% and 239% in L1210, 308% and 353% in P388, P < 0.01, for CHOP and AHOP respectively]. AHOP also proved to be more genotoxic and cytostatic than CHOP, inducing higher sister chromatid exchange levels and cell division delays on P388 cells in vivo. NSC290205 showed superior antineoplastic potential against lymphoid leukaemia and significant synergy with ADR, producing an excellent therapeutic outcome.
Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Azasteroids; Cell Death; Cyclophosphamide; Doxorubicin; Drug Evaluation, Preclinical; Drug Synergism; Humans; Leukemia, Experimental; Leukemia, Lymphoid; Male; Mice; Mice, Inbred Strains; Neoplasm Transplantation; Nitrogen Mustard Compounds; Prednisone; Survival Analysis; Tumor Cells, Cultured; Vincristine
PubMed: 15667536
DOI: 10.1111/j.1365-2141.2004.05315.x -
Journal of the American Chemical Society Jul 2004A conjugate of a DNA mismatch-specific rhodium intercalator, containing the bulky chrysenediimine ligand, and an aniline mustard has been prepared, and targeting of...
A conjugate of a DNA mismatch-specific rhodium intercalator, containing the bulky chrysenediimine ligand, and an aniline mustard has been prepared, and targeting of mismatches in DNA by this conjugate has been examined. The preferential alkylation of mismatched over fully matched DNA is found by a mobility shift assay at concentrations where untethered organic mustards show little reaction. The binding site of the Rh intercalator was determined by DNA photocleavage, and the position of covalent modification was established on the basis of the enhanced depurination associated with N-alkylation. The site-selective alkylation at mismatched DNA renders these conjugates useful tools for the covalent tagging of DNA base pair mismatches and new chemotherapeutic design.
Topics: 2,2'-Dipyridyl; Alkylating Agents; Alkylation; Base Pair Mismatch; Binding Sites; Chrysenes; DNA; Intercalating Agents; Ligands; Macromolecular Substances; Molecular Structure; Organometallic Compounds; Phenanthrolines; Rhodium; Substrate Specificity
PubMed: 15250697
DOI: 10.1021/ja048543m -
The Journal of Biological Chemistry Jun 1989The aziridinium of purified quinacrine mustard at 50 microM inactivates the bovine heart mitochondrial F1-ATPase with a pseudo-first order rate constant of 0.07 min-1 at...
The aziridinium of purified quinacrine mustard at 50 microM inactivates the bovine heart mitochondrial F1-ATPase with a pseudo-first order rate constant of 0.07 min-1 at pH 7.0 and 23 degrees C. An apparent Kd of 27 microM for the enzyme-reagent complex was estimated from the dependence of the rate of inactivation on the concentration of quinacrine mustard. The pH inactivation profile revealed that deprotonation of a group with a pKa of about 6.7 is necessary for inactivation. The amount of reagent incorporated into the protein increased linearly with the extent of inactivation. Complete inactivation was estimated to occur when 3 mol of reagent were incorporated/mol of F1. Enzyme, in which steady state ATPase was inactivated by 98% by quinacrine mustard, hydrolyzed substoichiometric ATP with zero order kinetics suggesting that residual activity is catalyzed by F1 in which at least one beta subunit is modified. By exploiting the reactivity of the aziridinium of covalently attached reagent with [3H] aniline, sites modified by quinacrine mustard were labeled with 3H. Isolation of radioactive cyanogen bromide peptides derived from F1 inactivated with the reagent in the presence of [3H]aniline which were identified by sequence analysis and sequence analyses of radioactive tryptic fragments arising from them have revealed the following. About two thirds of the radioactivity incorporated into the enzyme during inactivation is apparently esterified to one or more of the carboxylic acid side chains in a CNBr-tryptic fragment of the beta subunit with the sequence: 394DELSEEDK401. The remainder of the radioactivity is associated with at least two sites within the cyanogen bromide peptide containing residues 293-358 of the beta subunit. From these results it is concluded that inactivation of F1 by the aziridinium of quinacrine mustard is due, at least in part, to modification of one or more of the carboxylic acid side chains in the DELSEED segment of the beta subunit and possibly also to modification of unspecified amino acid side chains between residues 302-356 of the beta subunit.
Topics: Adenosine Triphosphate; Amino Acid Sequence; Aniline Compounds; Animals; Binding Sites; Cattle; Cyanogen Bromide; Enzyme Activation; Enzyme Stability; Hydrogen-Ion Concentration; Hydrolysis; Mitochondria, Heart; Molecular Probes; Molecular Sequence Data; Peptide Fragments; Proton-Translocating ATPases; Quinacrine; Quinacrine Mustard; Tritium
PubMed: 2524484
DOI: No ID Found -
Proceedings of the National Academy of... Dec 1996It is a goal of cancer chemotherapy to achieve the selective killing of tumor cells while minimizing toxicity to normal tissues. We describe the design of selective...
It is a goal of cancer chemotherapy to achieve the selective killing of tumor cells while minimizing toxicity to normal tissues. We describe the design of selective toxins forming DNA adducts that attract the estrogen receptor (ER), a transcription factor that is overexpressed in many human breast and ovarian tumors. The compounds consist of 4-(3-aminopropyl)-N,N-(2-chloroethyl)-aniline linked to 2-(4'-hydroxyphenyl)-3-methyl-5-hydroxy-indole. The former moiety is a DNA damaging nitrogen mustard and the latter is a ligand for the ER. The connection between these groups was refined to permit DNA adducts formed by the mustard portion of the molecule to present the ligand domain so that it was able to interact efficiently with the ER. By using 16-mers containing specific DNA adducts, it was determined that monoadducts and putative intrastrand crosslinks were preferred targets for the ER over interstrand crosslinks. A series of structurally related 2-phenylindole mustards was prepared, some of which were selectively toxic to the ER-positive breast cancer cell line MCF-7, as compared with the ER(-) negative line MDA-MB231. The ability both to bind to DNA and to interact significantly with the ER were essential to achieve selective lethality toward ER(+) cells. Compounds forming DNA adducts without the ability to bind receptor showed similar toxicities in the two cell lines. Several models could explain the selective toxicity of the mustard-phenylindole compounds toward ER(+) cells. The favored model suggests that a mustard-DNA adduct is shielded by the ER from DNA repair enzymes and hence cells possessing an abundance of the ER selectively retain the adduct and are killed.
Topics: Aniline Mustard; Antineoplastic Agents, Alkylating; Base Sequence; Binding Sites; Breast Neoplasms; Cell Line; Cell Survival; DNA; DNA Damage; Drug Design; Female; Humans; Molecular Structure; Nitrogen Mustard Compounds; Oligodeoxyribonucleotides; Ovarian Neoplasms; Receptors, Estrogen; Transcription Factors
PubMed: 8986764
DOI: 10.1073/pnas.93.26.15063 -
International Journal of Cancer Nov 1997We examined the in vivo efficacy of targeting beta-glucuronidase (betaG) to activate a glucuronide prodrug (BHAMG) of p-hydroxyaniline mustard (pHAM) at hepatoma ascites...
We examined the in vivo efficacy of targeting beta-glucuronidase (betaG) to activate a glucuronide prodrug (BHAMG) of p-hydroxyaniline mustard (pHAM) at hepatoma ascites in Sprague-Dawley rats. Injection i.p. of 500 microg RH1-betaG, a conjugate formed between recombinant betaG and monoclonal antibody RH1 with specificity for an antigen expressed on AS-30D rat hepatoma cells, into rats bearing AS-30D ascites resulted in the accumulation of 54 microg conjugate per 10(9) tumor cells after 2 hr. Ascites fluid and serum contained 0.53 and 0 microg/ml, respectively, RH1-betaG 2 hr after injection of the conjugate. Conjugate binding to AS-30D cells was heterogeneous and non-saturated, as determined by flow cytometry. BHAMG was less toxic than pHAM to SD rats based on measures of animal mortality, weight loss and hematological toxicity. Treatment of rats bearing established hepatoma ascites with 500 microg RH1-betaG followed 2 hr later with a single i.p. injection of 30 mg/kg BHAMG or 3 i.p. injections of 10 mg/kg BHAMG 2, 3 and 4 hr later resulted in the cure of 6/8 and 8/8 animals, respectively. Treatment with BHAMG or pHAM alone did not produce cures, whereas treatment with a control antibody-betaG conjugate and BHAMG produced significantly greater hematological toxicity compared to treatment with RH1-betaG and BHAMG. All cured rats were completely protected from rechallenge with 2 x 10(7) AS-30D cells, indicating that successful treatment of animals induced protective immunity.
Topics: Aniline Mustard; Animals; Antibodies, Monoclonal; Antineoplastic Agents; Ascites; Carcinoma, Hepatocellular; Glucuronidase; Immunotoxins; Leukocytes; Liver Neoplasms; Lymphocytes; Mice; Mice, Inbred BALB C; Mice, SCID; Prodrugs; Rats; Rats, Sprague-Dawley; Tumor Cells, Cultured
PubMed: 9359487
DOI: 10.1002/(sici)1097-0215(19971104)73:3<392::aid-ijc14>3.0.co;2-f -
British Journal of Cancer Mar 1999RHI-betaG-PEG, formed by linking poly(ethylene glycol)-modified beta-glucuronidase to Mab RH1, was employed to examine bystander killing of antigen-negative N1S1 rat...
RHI-betaG-PEG, formed by linking poly(ethylene glycol)-modified beta-glucuronidase to Mab RH1, was employed to examine bystander killing of antigen-negative N1S1 rat hepatoma cells by activation of a glucuronide prodrug (BHAMG) of p-hydroxyaniline mustard (pHAM) at antigen-positive AS-30D rat hepatoma cells. Sequential treatment of cells with 10 microg ml(-1) RH1-betaG-PEG and 20 microM BHAMG was not toxic to N1S1 cells but killed 99% of AS-30D cells. Over 98% of N1S1 cells, however, were killed in mixed populations containing as few as 2% AS-30D cells after identical treatment, demonstrating an in vitro bystander effect. Subcutaneous injection of AS-30D and N1S1 cells in BALB/c nu/nu mice produced solid tumours containing both cells. Uptake of radiolabelled RH1-betaG-PEG in solid AS-30D and mixed AS-30D/N1S1 tumours was 11.6 and 9.3 times greater than a control antibody conjugate 120 h after i.v. injection. Intravenous treatment with RH1-betaG-PEG and BHAMG cured seven of seven nude mice bearing solid s.c. AS-30D tumours and significantly delayed, compared with control conjugate and prodrug treatment, the growth of mixed N1S1/AS-30D tumours with one cure, showing that targeted activation of BHAMG kills bystander tumour cells in vivo.
Topics: Aniline Mustard; Animals; Antibodies, Monoclonal; Antineoplastic Agents, Alkylating; Diffusion; Drug Screening Assays, Antitumor; Glucuronidase; Immunohistochemistry; Immunotoxins; Liver Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Mice, Nude; Polyethylene Glycols; Prodrugs; Rats; Rats, Sprague-Dawley; Time Factors; Tumor Cells, Cultured
PubMed: 10188879
DOI: 10.1038/sj.bjc.6690221