MDR1 Gene-transfected Mouse Lymphoma Research Articles

Antibacterial Activity and Reversal of Multidrug Resistance of Tumor Cells by Essential Oils from Fresh Leaves, Flowers, and Stems of Montanoa quadrangularis Schultz Bipontinus (Asteraceae) Collected in Mérida-Venezuela.

Essential oils obtained by hydrodistillation of Montanoa quadrangularis leaves, flowers, and stems were analyzed by GC and GC/MS techniques revealing myrcene, limonene, β-phellandrene, and sabinene among the main components. The aim of the present study was to evaluate the MDR modulator activity on human MDR1 gene transfected mouse lymphoma cell line and the antimicrobial activity on the essential oils obtained from different parts of the species under investigation. The results revealed that MQL caused a similar increase in the fluorescence activity of the cells at 0.02 μL/mL comparing to the Verapamil® value. The antimicrobial assay was carried out according to the disc diffusion method. Five different bacterial strains (Staphylococcus epidermidis, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli AG 100, and Escherichia coli AG100A) were treated with the essential oils and the zones of inhibition were determined on TSA plates and TSA agar plates supplemented with Tween 20. MQF and MQL showed activity against B. subtilis, S. epidermidis, and E. coli AG 100A while MQS was only active against E. coli AG 100A on TSA agar plates experiment. In case of TSA agar plates supplemented with 0.1 v/v% Tween 20 detergent, MQF showed inhibition on B. subtilis, S. epidermidis, and E. coli AG 100A; MQL was active against B. subtilis, E. coli AG 100, and E. coli AG 100A while MQS was only active against E. coli AG 100A.

Jatrophane Diterpenes from Euphorbia mellifera and Their Activity as P-Glycoprotein Modulators on Multidrug-Resistant Mouse Lymphoma and Human Colon Adenocarcinoma Cells

Three new macrocyclic jatrophane diterpenes, named euphomelliferine (1) and euphomelliferenes A (2) and B (3), and one new tetracyclic triterpene, 19(10→9)-abeo-8α,9β,10α-tirucalla-5,25-diene-3β,24-diol (6, C-24 epimers), were isolated from the methanolic extract of Euphorbia mellifera. A known ingenane (7) and two jatrophane diterpenes (4 and 5) were also isolated. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D homo- and heteronuclear NMR experiments. Jatrophane diterpenes 1-3 and 5 were evaluated for their effects on the reversion of multidrug resistance (MDR) mediated by P-glycoprotein, by using the rhodamine-123 exclusion test, on human MDR1 gene-transfected mouse lymphoma cells (L5178Y MDR) and on human colon adenocarcinoma cells (COLO 320). The apoptosis-inducing activity of these compounds was also tested on COLO 320 cells, using the annexin-V/propidium iodide assay. Diterpenes 1 and 2 displayed significant MDR reversing activity, in a dose-dependent manner, on both cancer cell models. The tested compounds did not induce apoptosis in the COLO 320 cells.

Structure activity-relationships of P-Glycoprotein modulation using a small library of macrocyclic lathyrane diterpenes

Multidrug resistance is a major hurdle for the success of cancer chemotherapy. The main cause for this phenomenon is attributed to the overexpression of the efflux pump, P-glycoprotein (P-gp). A small library of novel bioactive macrocyclic lathyrane-type diterpene derivatives was developed to discover a selective P-gp reversal agent. In this way, a macrocyclic diterpene was acylated with different alkanoyl and aroyl anhydrides/chlorides. In order to explore the role of the substitution pattern on the modulation of P-gp efflux, the anti-MDR effects of compounds were evaluated in human MDR1-gene transfected mouse lymphoma cells, through the rhodamine-123 exclusion assay.

Synthesis, characterization and anticancer activity of 3-aza-analogues of DP-7

From the recent studies, 3,5-dibenzoyl-1,4-dihydropyridone (DHP) derivatives, DP-7, has emerged as a potent multidrug reverting agent that inhibits efflux of drug from cell wall by inhibiting the activity of ATP Binding Cassettes. On the other hand, dihydropyrimidine (DHPM) derivative, (aza analogue) namely, monastrol inhibits the protein Eg5, which is responsible for the separation of daughter chromosomes during cell division and controls the growth of the tumor cells. In the present report, we have reported the hybridize molecules of these two potent molecules to check the dual action in cancer chemotherapy by synthesizing various thio and oxo analogues, bearing substituted aryl groups at 4th position of the DHPM ring. The newly synthesized molecules were screened for antiproliferative effects in mdr1-gene transfected mouse lymphoma cell line (l5178 y). Among these newly synthesized compounds namely, II h, I g, I i, and I j showed a very potent antiproliferative activity.

Synthesis of some novel benzofuran-2-yl(4,5-dihyro-3,5-substituted diphenylpyrazol-1-yl) methanones and studies on the antiproliferative effects and reversal of multidrug resistance of human MDR1-gene transfected mouse lymphoma cells in vitro

A new series of benzofuran-2-yl(4,5-diydro-3,5-substituted diphenylpyrazol-1-yl) methanone derivatives 8a– x by the reaction of the benzofuran-2-carbohydrazides 7 with various chalcone derivatives 3a– x using microwave irradiation has been described. The effect of synthesized compounds 8a– v was studied against human cancer cell lines for their antiproliferative activity and reversal of multidrug resistance on human MDR1-gene transfected mouse lymphoma cells. Among the 24 compounds, the 8c and 8h showed good antiproliferative activity 8b, 8f and 8k were exhibited good MDR reversal activity. The main significance of the process is easy workup process, short reaction time and high yield of the new compounds for biological interest. However, the studies on genetically modified multidrug resistant cancer cells are costly and time consuming.

Comparative Study on the MDR Reversal Effects of Selected Chalcones.

Based on the structure of three previously established lead compounds, fifteen selected chalcones were synthesized and evaluated for their multidrug resistance (MDR) reversal activity on mouse lymphoma cells. The most active chalcones were stronger revertants than the positive control, verapamil. In the model of combination chemotherapy, the interactions between the anticancer drug doxorubicin and two of the most effective compounds were measured in vitro, on human MDR1 gene transfected mouse lymphoma cells, showing that the type of interaction for one of these compounds was indifferent while that for the other one was additive. Furthermore, two chalcones inhibited 50% of cell proliferation in concentration of around 0.4 μg/mL and were from 2- to 100-fold more active than the most chalcones. The structure-activity relationships were obtained and discussed in view of their usefulness for the design of chalcone-like P-gp modulators and drugs able to treat resistant cancers.

Reversal of Multidrug Resistance by Natural Substances from Plants

The multidrug resistance (MDR) proteins that belong to the ATP-binding cassette superfamily such as P-glycoprotein (P-gp) and MRP1, are present in a majority of human tumors and constitute an important cause of therapeutic failure. Selective inhibitors of the MDR-efflux proteins may improve the effectiveness of cancer chemotherapy. Their mechanism of action was believed to be a competition between resistance modifiers and drugs for the same binding site of P-gp. In our previous work we studied modulation of MDR in cancer cells expressing P-gp or MRP1 by selected carotenoids, flavonoids and extracts from medically important Chinese plants. Capsanthin and capsorubin, carotenoids isolated from paprika, were identified as potent P-gp inhibitors, while lycopene, lutein, antheraxanthin and violaxanthin induced moderate effects. Among flavonoids, effective modulators were rotenone, chrysin, phloretin and sakuranetin. Some chloroform extracts of Chinese herbs were also found to inhibit MDR efflux pumps. The effects of the modulators on P-gp activity were studied by measuring rhodamine 123 uptake in several cancer cells such as the human MDR1 gene-transfected mouse lymphoma cells (L1210) and human breast cancer cells MDA-MB-231 expressing the MRP1 pump (HTB26). Additionally, the ability to alter biophysical properties of lipid bilayers by selected carotenoids was studied by differential scanning calorimetry. The antiproliferative effects as well as the MDR reversal activity of the studied compounds, applied in combination with anticancer drugs, were also discussed.

Ecdysteroids reverse resistance of human mdr1 gene transfected mouse lymphoma cells

Ecdysteroids reverse resistance of human mdr1 gene transfected mouse lymphoma cells

New potent P-glycoprotein modulators with the cucurbitane scaffold and their synergistic interaction with doxorubicin on resistant cancer cells

The novel cucurbitacins, balsaminagenin A and B ( 1– 2) and balsaminoside A ( 3) and the know cucurbitacin karavelagenin C ( 4), together with five new mono or diacylated derivatives ( 5– 9) of karavelagenin C were evaluated for multidrug resistance reversing activity on human MDR1 gene transfected mouse lymphoma cells. Compounds 2– 6 exhibited a strong activity compared with that of the positive control, verapamil. Structure–activity relationships are discussed. Moreover, in the checkerboard model of combination chemotherapy, the interaction between doxorubicin and compounds 2– 5 synergistically enhanced the effect of the anticancer drug. Compounds 1– 4 were isolated from the aerial parts of Momordica balsamina L . The structures of the compounds were established on the basis of spectroscopic methods including 2D NMR experiments (COSY, HMQC, HMBC and NOESY).

Purification and identification of active compounds of Carpobrotus edulis against the reversal of resistance of human mdr1 gene transfected mouse lymphoma cells

Purification and identification of active compounds of Carpobrotus edulis against the reversal of resistance of human mdr1 gene transfected mouse lymphoma cells

Apoptosis induction and modulation of P-glycoprotein mediated multidrug resistance by new macrocyclic lathyrane-type diterpenoids

The macrocyclic lathyrane diterpenes, latilagascenes D–F ( 1– 3) and jolkinol B ( 4), were isolated from the methanol extract of Euphorbia lagascae, and evaluated for multidrug resistance reversing activity on mouse lymphoma cells. All compounds displayed very strong activity compared with that of the positive control, verapamil. The structure–activity relationship is discussed. The evaluation of compounds 1 and 4, and of latigascenes A-C ( 5– 7), isolated from the same species, as apoptosis-inducers was also carried out. Compound 1 was the most active. Furthermore, in the model of combination chemotherapy, the interaction between the doxorubicine and latilagascene B ( 6) was studied in vitro, on human MDR1 gene transfected mouse lymphoma cells, showing that the type of interaction was synergistic. Latilagascenes D–F ( 1– 3) are new compounds whose structures were established on the basis of spectroscopic methods, including 2D NMR experiments (COSY, HMQC, HMBC and NOESY).

New Macrocyclic Lathyrane Diterpenes, fromEuphorbia lagascae,as Inhibitors of Multidrug Resistance of Tumour Cells

The new macrocyclic lathyrane diterpenes latilagascenes A and B ( 1 and 2), the diacetylated derivative of 2, latilagascene C ( 3), and the known diterpenes ent-16alpha,17-dihydroxyatisan-3-one ( 4) and ent-16alpha,17-dihydroxykauran-3-one ( 5), isolated from the methanol extract of Euphorbia lagascae, were examined for their effects on the reversal of multidrug resistance (MDR) on mouse lymphoma cells. Among the active lathyrane derivatives 1 - 3, compound 2 displayed the highest inhibition of rhodamine 123 efflux of human MDR1 gene transfected mouse lymphoma cells when compared to the untreated cells or the positive control verapamil. The new compounds are the first macrocyclic lathyrane diterpenes showing oxidation at C-16, whose structures were characterized by extensive spectroscopic methods, including 2D NMR experiments ( (1)H- (1)H COSY, HMQC, HMBC and NOESY). The known phenolic compounds vanillic acid ( 6), p-salicylic acid ( 7), isofraxidin ( 8) and cleomiscosin A ( 9) were also isolated from this species.