Perspectives of inhibition of multidrug resistance during cancer chemotherapy, in vitro and in vivo experiments

2009 ◽  
Vol 150 (13) ◽  
pp. 607-614
Author(s):  
Helga Engi
Keyword(s):  
Multidrug Resistance ◽  
Cancer Chemotherapy ◽  
In Vivo Experiments

A daganatos megbetegedések elleni küzdelem hatásosságában a multidrog-rezisztencia kérdésének megoldása fontos szerepet játszik. Növekvő igény mutatkozik olyan új vegyületek kifejlesztésére, amelyek képesek gátolni a különböző rezisztenciamechanizmusokat. Célul tűztük ki a szintetikus (cinnamilidén-ketonok; 1,4-dihidropiridin és fenotiazinszármazékok; hősokkfehérje-90-gátló peptidek és Tilozin betti bázisú származék), valamint természetes ( Euphorbia -diterpének) növényi alkotókból kivont származékok multidrog-rezisztenciáért felelős effluxpumpa-gátlásának vizsgálatát különböző sejtvonalakon, remélve, hogy a verapamiltól kevésbé toxikus, de annál hatásosabb rezisztenciamódosító vegyületeket találunk. A tézis első része a vizsgált vegyületek P-glikoprotein effluxpumpa-gátló hatását mutatja be különböző sejtvonalakon. Általánosságban elmondható, hogy az újonnan azonosított rezisztenciamódosító vegyületek képesek voltak a kiválasztott rákellenes szerek sejtszaporodás-gátló hatásának fokozására, köcsönhatásuk szinergizáló vagy additív hatást mutatott in vitro kísérletekben. A Tilozin betti bázisú származék in vitro kísérletekben tapasztalt hatását, további in vivo , DBA/2 egér modellek alátámasztották. Az antitumorhatás vizsgálatának egy alternatív útja a különböző vegyületekkel kiváltott apoptózis folyamata. A legígéretesebb apoptózisindukálónak a dihidropiridin 13 bizonyult. A latrán vegyületek antipromóciós hatásának in vitro modellezéséhez humán cytomegalovirussal fertőzött humán tüdőráksejteket használtunk. A vizsgált makrociklikus latrán típusú diterpén vegyületek többsége, kivéve a latilagascene D vegyület, képes volt a cytomegalovirus korai antigén-kifejeződésének gátlására.

scholarly journals Overcoming multidrug-resistance in vitro and in vivo using the novel P-glycoprotein inhibitor 1416

2012 ◽  
Vol 32 (6) ◽  
pp. 559-566 ◽  
Author(s):  
Yan Xu ◽  
Feng Zhi ◽  
Guangming Xu ◽  
Xiaolei Tang ◽  
Sheng Lu ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Cancer Chemotherapy ◽  
Antitumour Activity ◽  
Multidrug Resistant ◽  
The Novel ◽  
Mice Model ◽  
P Glycoprotein ◽  
Channel Currents

MDR (multidrug-resistance) represents a major obstacle to successful cancer chemotherapy and is usually accomplished by overexpression of P-gp (P-glycoprotein). Much effort has been devoted to developing P-gp inhibitors to modulate MDR. However, none of the inhibitors on the market have been successful. 1416 [1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino)propane hydrochloride (phenoprolamine hydrochloride)] is a new VER (verapamil) analogue with a higher IC50 for blocking calcium channel currents than VER. In the present paper, we examined the inhibition effect of 1416 on P-gp both in vitro and in vivo. 1416 significantly enhanced cytotoxicity of VBL (vinblastine) in P-gp-overexpressed human multidrug-resistant K562/ADM (adriamycin) and KBV cells, but had no such effect on the parent K562 and KB cells. The MDR-modulating function of 1416 was further confirmed by increasing intracellular Rh123 (rhodanmine123) content in MDR cells. Human K562/ADM xenograft-nude mice model verified that 1416 potentiates the antitumour activity of VBL in vivo. RT-PCR (reverse transcriptase-PCR) and FACS analysis demonstrated that the expression of MDR1/P-gp was not affected by 1416 treatment. All these observations suggest that 1416 could be a promising agent for overcoming MDR in cancer chemotherapy.

Reversal of P-glycoprotein-medicated multidrug resistance by LBM-A5 in vitro and a study of its pharmacokinetics in vivo

2015 ◽  
Vol 93 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Tianxiao Zhao ◽  
Yun Song ◽  
Baomin Liu ◽  
Qianqian Qiu ◽  
Lei Jiao ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Cancer Chemotherapy ◽  
Anticancer Agents ◽  
Efflux Pump ◽  
Therapeutic Index ◽  
Intracellular Accumulation ◽  
P Glycoprotein ◽  
Reversal Mechanism

The overexpression of P-glycoprotein (P-gp) in tumors leads to multidrug resistance (MDR), which is a significant obstacle in clinical cancer chemotherapy. The co-administration of anticancer drugs and MDR modulators is a promising strategy for overcoming this problem. Our study aimed to explore the reversal mechanism and safety of the MDR modulator LBM-A5 in vitro, and evaluate its pharmacokinetics and effects on doxorubicin metabolism in vivo. We evaluated an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay of anticancer agents mediated by LBM-A5, the effect of LBM-A5 on rhodamine123 intracellular accumulation, and the efflux in K562/DOX cells to investigate the reversal mechanisms of LBM-A5. The results showed that LBM-A5 inhibits rhodamine123 efflux and increases intracellular accumulation by inhibiting the efflux pump function of P-gp. Furthermore, the therapeutic index and CYP3A4 activity analysis in vitro suggested that LBM-A5 is reasonably safe to use. Also, LBM-A5 (10 mg/kg body mass) achieved the required plasma concentration in sufficient time to reverse MDR in vivo. Importantly, the LBM-A5 treatment group shared similar doxorubicin (DOX) pharmacokinetics with the free DOX group. Our results suggest that LBM-A5 effectively reverses MDR (EC50 = 483.6 ± 81.7 nmol·L−1) by inhibiting the function of P-gp, with relatively ideal pharmacokinetics and in a safe manner, and so may be a promising candidate for cancer chemotherapy research.

scholarly journals Two-pronged anti-tumor therapy by a new polymer-paclitaxel conjugate micelle with an anti-multidrug resistance effect

2021 ◽  
Author(s):  
Juan Du ◽  
Lanlan Zong ◽  
Mengmeng Li ◽  
Yonghui Qiao ◽  
Keke Yu ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Human Life ◽  
Tumor Therapy ◽  
Subcutaneous Tumor ◽  
Tumor Bearing ◽  
In Vivo Experiments ◽  
Alternative Delivery ◽  
Mcf 7

Abstract Cancerous tumors are still a major disease that threatens human life, with tumor multidrug resistance (MDR) being one of the main reasons for the failure of chemotherapy. Here, a reduction-sensitive polymer prodrug micelle, mPEG-DCA-SS-PTX (PDSP), was manufactured with a new polymer inhibitor of drug-resistance as a carrier to overcome MDR and improve the anti-tumor effect of paclitaxel (PTX). The PDSP micelles display good stability, double-responsive drug release, and excellent biocompatibility. The PDSP micelles reduced the cytotoxicity of PTX to normal HL-7702 cells, and enhanced that to SMMC-7721 and MCF-7 cells in vitro. Improved sensitivity of A549/ADR to PDSP was also observed in vitro. Furthermore, in vivo experiments show reduced systemic toxicity and enhanced therapeutic efficacy of DOX to H22 subcutaneous tumor-bearing mice. This work proves the reduction sensitive polymer prodrug micelles carried by the new polymer inhibitor can be used as an alternative delivery system to target tumors and reverse MDR for paclitaxel and other tumor-resistant drugs.

scholarly journals Dual Regulation of the Bacillus subtilis Regulon Comprising the lmrAB and yxaGH Operons and yxaF Gene by Two Transcriptional Repressors, LmrA and YxaF, in Response to Flavonoids

2007 ◽  
Vol 189 (14) ◽  
pp. 5170-5182 ◽  
Author(s):  
Kazutake Hirooka ◽  
Satoshi Kunikane ◽  
Hiroshi Matsuoka ◽  
Ken-Ichi Yoshida ◽  
Kanako Kumamoto ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Multidrug Resistance ◽  
Promoter Region ◽  
Consensus Sequence ◽  
Transcriptional Repressors ◽  
Promoter Regions ◽  
In Vivo Experiments ◽  
Dnase I Footprinting

ABSTRACT Bacillus subtilis LmrA is known to be a repressor that regulates the lmrAB and yxaGH operons; lmrB and yxaG encode a multidrug resistance pump and quercetin 2,3-dioxygenase, respectively. DNase I footprinting analysis revealed that LmrA and YxaF, which are paralogous to each other, bind specifically to almost the same cis sequences, LmrA/YxaF boxes, located in the promoter regions of the lmrAB operon, the yxaF gene, and the yxaGH operon for their repression and containing a consensus sequence of AWTATAtagaNYGgTCTA, where W, Y, and N stand for A or T, C or T, and any base, respectively (three-out-of-four match [in lowercase type]). Gel retardation analysis indicated that out of the eight flavonoids tested, quercetin, fisetin, and catechin are most inhibitory for LmrA to DNA binding, whereas quercetin, fisetin, tamarixetin, and galangin are most inhibitory for YxaF. Also, YxaF bound most tightly to the tandem LmrA/YxaF boxes in the yxaGH promoter region. The lacZ fusion experiments essentially supported the above-mentioned in vitro results, except that galangin did not activate the lmrAB and yxaGH promoters, probably due to its poor incorporation into cells. Thus, the LmrA/YxaF regulon presumably comprising the lmrAB operon, the yxaF gene, and the yxaGH operon is induced in response to certain flavonoids. The in vivo experiments to examine the regulation of the synthesis of the reporter β-galactosidase and quercetin 2,3-dioxgenase as well as that of multidrug resistance suggested that LmrA represses the lmrAB and yxaGH operons but that YxaF represses yxaGH more preferentially.

ANTITUMOR EFFECT OF COLLOIDAL SILVER BISILICATE IN EXPERIMENTAL IN VITRO AND IN VIVO STUDIES

2019 ◽  
Vol 65 (5) ◽  
pp. 760-765
Author(s):  
Margarita Tyndyk ◽  
Irina Popovich ◽  
A. Malek ◽  
R. Samsonov ◽  
N. Germanov ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Tumor Growth ◽  
Tumor Cells ◽  
Human Tumor ◽  
Significant Inhibition ◽  
In Vivo Studies ◽  
Ehrlich Carcinoma ◽  
In Vivo Experiments

The paper presents the results of the research on the antitumor activity of a new drug - atomic clusters of silver (ACS), the colloidal solution of nanostructured silver bisilicate Ag6Si2O7 with particles size of 1-2 nm in deionized water. In vitro studies to evaluate the effect of various ACS concentrations in human tumor cells cultures (breast cancer, colon carcinoma and prostate cancer) were conducted. The highest antitumor activity of ACS was observed in dilutions from 2.7 mg/l to 5.1 mg/l, resulting in the death of tumor cells in all studied cell cultures. In vivo experiments on transplanted Ehrlich carcinoma model in mice consuming 0.75 mg/kg ACS with drinking water revealed significant inhibition of tumor growth since the 14th day of experiment (maximally by 52% on the 28th day, p < 0.05) in comparison with control. Subcutaneous injections of 2.5 mg/kg ACS inhibited Ehrlich's tumor growth on the 7th and 10th days of the experiment (p < 0.05) as compared to control.

scholarly journals Plant-Derived Extracellular Vesicles: Current Findings,Challenges, and Future Applications

Membranes ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 411
Author(s):  
Nader Kameli ◽  
Anya Dragojlovic-Kerkache ◽  
Paul Savelkoul ◽  
Frank R. Stassen
Keyword(s):  
Human Health ◽  
Extracellular Vesicles ◽  
Preliminary Results ◽  
In Vivo Experiments ◽  
Health And Disease ◽  
Conducting Research ◽  
Protocol Standardization ◽  
Insight Into

In recent years, plant-derived extracellular vesicles (PDEVs) have gained the interest of many experts in fields such as microbiology and immunology, and research in this field has exponentially increased. These nano-sized particles have provided researchers with a number of interesting findings, making their application in human health and disease very promising. Both in vitro and in vivo experiments have shown that PDEVs can exhibit a multitude of effects, suggesting that these vesicles may have many potential future applications, including therapeutics and nano-delivery of compounds. While the preliminary results are promising, there are still some challenges to face, such as a lack of protocol standardization, as well as knowledge gaps that need to be filled. This review aims to discuss various aspects of PDEV knowledge, including their preliminary findings, challenges, and future uses, giving insight into the complexity of conducting research in this field.

scholarly journals Osteoprotective Effects of Loganic Acid on Osteoblastic and Osteoclastic Cells and Osteoporosis-Induced Mice

2020 ◽  
Vol 22 (1) ◽  
pp. 233
Author(s):  
Eunkuk Park ◽  
Chang Gun Lee ◽  
Eunguk Lim ◽  
Seokjin Hwang ◽  
Seung Hee Yun ◽  
...  
Keyword(s):  
Osteoclast Differentiation ◽  
Osteoblastic Differentiation ◽  
Common Disease ◽  
Root Extract ◽  
Mouse Bone Marrow ◽  
Mineral Density ◽  
Bone Mineral Density Loss ◽  
In Vivo Experiments

Osteoporosis is a common disease caused by an imbalance of processes between bone resorption by osteoclasts and bone formation by osteoblasts in postmenopausal women. The roots of Gentiana lutea L. (GL) are reported to have beneficial effects on various human diseases related to liver functions and gastrointestinal motility, as well as on arthritis. Here, we fractionated and isolated bioactive constituent(s) responsible for anti-osteoporotic effects of GL root extract. A single phytochemical compound, loganic acid, was identified as a candidate osteoprotective agent. Its anti-osteoporotic effects were examined in vitro and in vivo. Treatment with loganic acid significantly increased osteoblastic differentiation in preosteoblast MC3T3-E1 cells by promoting alkaline phosphatase activity and increasing mRNA expression levels of bone metabolic markers such as Alpl, Bglap, and Sp7. However, loganic acid inhibited osteoclast differentiation of primary-cultured monocytes derived from mouse bone marrow. For in vivo experiments, the effect of loganic acid on ovariectomized (OVX) mice was examined for 12 weeks. Loganic acid prevented OVX-induced bone mineral density loss and improved bone structural properties in osteoporotic model mice. These results suggest that loganic acid may be a potential therapeutic candidate for treatment of osteoporosis.

scholarly journals Regorafenib-Attenuated, Bleomycin-Induced Pulmonary Fibrosis by Inhibiting the TGF-β1 Signaling Pathway

2021 ◽  
Vol 22 (4) ◽  
pp. 1985
Author(s):  
Xiaohe Li ◽  
Ling Ma ◽  
Kai Huang ◽  
Yuli Wei ◽  
Shida Long ◽  
...  
Keyword(s):  
Pulmonary Fibrosis ◽  
Signaling Pathway ◽  
Transforming Growth Factor ◽  
Kinase Inhibitor ◽  
In Vivo Experiments ◽  
Age Related ◽  
And Migration ◽  
Tgf Β1

Idiopathic pulmonary fibrosis (IPF) is a fatal and age-related pulmonary disease. Nintedanib is a receptor tyrosine kinase inhibitor, and one of the only two listed drugs against IPF. Regorafenib is a novel, orally active, multi-kinase inhibitor that has similar targets to nintedanib and is applied to treat colorectal cancer and gastrointestinal stromal tumors in patients. In this study, we first identified that regorafenib could alleviate bleomycin-induced pulmonary fibrosis in mice. The in vivo experiments indicated that regorafenib suppresses collagen accumulation and myofibroblast activation. Further in vitro mechanism studies showed that regorafenib inhibits the activation and migration of myofibroblasts and extracellular matrix production, mainly through suppressing the transforming growth factor (TGF)-β1/Smad and non-Smad signaling pathways. In vitro studies have also indicated that regorafenib could augment autophagy in myofibroblasts by suppressing TGF-β1/mTOR (mechanistic target of rapamycin) signaling, and could promote apoptosis in myofibroblasts. In conclusion, regorafenib attenuates bleomycin-induced pulmonary fibrosis by suppressing the TGF-β1 signaling pathway.

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