ABCG2-overexpressing S1-M1-80 cell xenografts in nude mice keep original biochemistry and cell biological properties / 癌症

S1-M1-80 cells, derived from human colon carcinoma S1 cells, are mitoxantrone-selected ABCG2-overexpressing cells and are widely used in in vitro studies of multidrug resistance(MDR). In this study, S1-M1-80 cell xenografts were established to investigate whether the MDR phenotype and cell biological properties were maintained in vivo. Our results showed that the proliferation, cell cycle, and ABCG2 expression level in S1-M1-80 cells were similar to those in cells isolated from S1-M1-80 cell xenografts (named xS1-M1-80 cells). Consistently, xS1-M1-80 cells exhibited high levels of resistance to ABCG2 substrates such as mitoxantrone and topotecan, but remained sensitive to the non-ABCG2 substrate cisplatin. Furthermore, the specific ABCG2 inhibitor Ko143 potently sensitized xS1-M1-80 cells to mitoxantrone and topotecan. These results suggest that S1-M1-80 cell xenografts in nude mice retain their original cytological characteristics at 9 weeks. Thus, this model could serve as a good system for further investigation of ABCG2-mediated MDR.

Inhibitory effect of apatinib on HL-60 cell proliferation and its mechanism / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of apatinib, a small-molecule vascular endothelial growth factor receptor-2 tyrosine kinase inhibitor, on the proliferation of human acute myeloid leukemia HL-60 cells and explore the possible mechanism.</p><p><b>METHODS</b>MTT assay was used to assess the cytotoxicity of apatinib in HL-60 cells. The apoptosis and cell cycle changes of the cells in response to apatinib treatment were analyzed by flow cytometry, and Western blotting was used to assay P-Akt and P-Erk1/2 expressions in the cells.</p><p><b>RESULTS</b>Apatinib significantly inhibited the proliferation of HL-60 cells in vitro with an IC(50) of 4.96∓0.32 µmol/L. Apatinib treatment significantly increased the apoptotic rate of the cells in a dose-dependent manner, but produced no significant effect on the cell cycle (P>0.05). Western blotting showed that the expressions of P-Akt and P-Erk1/2 decreased in HL-60 cells after a 48-h apatinib treatment.</p><p><b>CONCLUSION</b>Apatinib inhibits the proliferation of HL-60 cells by inducing cell apoptosis probably through the mechanism of inhibiting the expressions of the Akt/Erk1/2 signal transduction pathway.</p>

Multidrug resistance-associated proteins and their roles in multidrug resistance / 药学学报

Multidrug resistance (MDR) is a major impediment to the success of cancer chemotherapy. Multidrug resistance-associated proteins (MRPs) play an important role in the process of MDR. As an ATP-binding cassette (ABC) transporter superfamily, MRPs are selective and specific drug efflux pumps. In this paper, physiological characteristics, structural characteristics and resistance profile of MRPs and the associated reversal studies are reviewed.

A cell-based screen for anticancer activity of 13 pyrazolone derivatives / 癌症

<p><b>BACKGROUND AND OBJECTIVE</b>Pyrazolone derivatives were reported to have a potent cytotoxicity against some tumor cells. In the present study, we evaluated the cytotoxic activity of a series of pyrazolone derivatives against four human tumor cell lines including HepG2, OVCAR3, KB, and multidrug resistance (MDR) KBv200 cell lines in vitro and in vivo. Additionally, the structure-activity relationships of these compounds were discussed.</p><p><b>METHODS</b>To analyze the antiproliferative potential of the synthesized compounds against several human tumor cell lines, the 50% inhibitory concentration (IC50) values were determined by MTT assay. Besides, the KBv200 cell xenograft experimental model was established and the sensitivity to the pyrazolone compounds was compared between drug-sensitive parental KB cells and MDR KBv200 cells.</p><p><b>RESULTS</b>Of 13 compounds screened, compound 9 presented remarkable anticancer effects, of which IC50 values were (3.24 ± 0.28), (2.58 ± 0.61), (3.81 ± 0.02), and (3.45 ± 0.03) μg/mL in HepG2, OVCAR3, KB and MDR KBv200 cells, respectively (P > 0.05). Furthermore, compound 9 effectively inhibited tumor growth of KBv200 cell xenografts in vivo, the inhibition ratio was 25.37%, 38.43%, and 47.50% for 1.5 mg/kg, 3 mg/kg, and 6 mg/kg of compound 9 groups, respectively.</p><p><b>CONCLUSION</b>Compound 9 was the most promising antitumor agent in this study.</p>

Progress of individualized chemotherapy guided by chemosensitivity test / 药学学报

In spite of receiving chemotherapy, the response of patients with cancer can be extremely variable. Chemosensitivity testing is being applied in institutes and some hospitals to improve the effects of chemotherapy. It would be useful for choosing the most effective drug and strategy for individual chemotherapy and to exclude the resistance of the tumor cells. In this way, the individualized chemotherapy can be established. Up to today, there are more than 10 approaches established for chemosensitivity testing assays, such as single cell culture assay (including MTT, MTS, ATP), nude mouse model sensitivity examination, collagen gel droplet embedded culture drug sensitivity test and histoculture drug response assay etc. This paper reviews some current methods, and their possibility for directing clinical chemotherapy.

Advance of several types of important marine antitumor drugs / 药学学报

Marine antitumor drugs have been the research focus in the world. Recently, advancement has been made in the investigation of six types of compounds including bryostatin-1, ecteinascidin-743, dolastatin, didemnin B, psammaplin and halichondrin B. In this review, we summarized the recent research progress of the above mentioned marine antitumor drugs and their derivatives. Also, the development tendency of marine antitumor drugs was discussed.

Advances in the study of expression and regulation of P-glycoprotein / 药学学报

Resistance to the cytotoxic actions of antineoplastic drugs remains a barrier to the establishment of curative chemotherapy regimens for cancer. Over-expression of P-glycoprotein (P-gp), encoded by the MDR1 gene is the major molecular mechanism enhancing efflux pump for various anticancer agents, hence caused MDR. Transcription factor, DNA methylation, histone acetylation/deacetylation, phosphorylation and glycosylation and MDR1 gene polymorphisms play pivotal role in regulation of P-glycoprotein, and may become new therapeutic targets. This paper summarized the advances of studies on expression and regulation of P-glycoprotein.

Induction of apoptosis of tumor multidrug resistance cell by uvarigrin and its mechanism / 药学学报

<p><b>AIM</b>To study the effect of uvarigrin on mitochondrial dependent pathway during the apoptosis induced by it in MDR KBv200 cells and their parental sensitive KB cells.</p><p><b>METHODS</b>MTT assay was used to detect the cytotoxic effect of uvarigrin on KBv200 and KB cells. Annexin V FITC staining identified uvarigrin-induced apoptosis in KBv200 and KB cells. These cells underwent incubation with DCFH-DA, or DiOC6, followed by flowcytometry for the measurement of reactive oxygen species (ROS) and mitochondrial membrane potential (deltapsim), respectively. The Western blotting analysis was performed on Caspase-9 activation.</p><p><b>RESULTS</b>Uvarigrin inhibited the growth of KBv200 cells and KB cells in vitro. Most of the uvarigrin-induced cells death was found to be due to apoptosis, as determined by Annexin V FITC staining. During the apoptosis, the level of ROS increased while the level of deltapsim decreased in a time-dependent manner. Uvarigrin triggered Caspase-9 activation.</p><p><b>CONCLUSION</b>Uvarigrin induced apoptosis in KBv200 cells and KB cells probably through a mitochondria-dependent pathway.</p>

Apoptosis of human carcinoma of mouth floor KB cells and multidrug resistant KBv200 cells induced by azide methyl anthraquinone derivative / 药学学报

<p><b>AIM</b>To determine the effects of azide methyl anthraquinone derivative (AMAD) on growth inhibition and inducing apoptosis of multidrug resistant (MDR) KBv200 cells and parental drug-sensitive KB cells.</p><p><b>METHODS</b>Cytotoxicity was determined by tetrazolium (MTF) assay. Reactive oxygen species (ROS) levels and mitochondrial membrane potential (deltapsi(m)) in cells were labeled with DCFH-DA and DiOC6 and tested by flow cytometry. Annexin V stain and DNA ladder were used to examine the apoptosis of KB and KBv200 cells induced by AMAD.</p><p><b>RESULTS</b>AMAD was shown to inhibit the growth of KB and KBv200 cells significantly in a concentration-dependent manner, with mean IC50 of 0.36 and 0.45 micromol x L(-1), respectively. The generation of ROS increased obviously after the cells were treated with AMAD for 12 h, up to the peak in 24 h, meanwhile the levels of deltapsi(m) were time-dependently decreased. DNA fragmentation appeared on the agarose gel. Annexin V stain showed AMAD induced apoptosis of KB and KBv200 cells also in a concentration-dependent manner.</p><p><b>CONCLUSION</b>AMAD showed inhibitory effect on both MDR KBv200 cells and parental drug-sensitive KB cells. The mechanism of action was associated with the increase of the cellular ROS level and the decrease of the mitochondrial membrane potential induced by AMAD, which result in cell apoptosis.</p>

Synthesis and antitumour activities of some pteridine derivatives / 药学学报

<p><b>AIM</b>To study the synthesis and antitumour activities of some aryl-substituted pteridines.</p><p><b>METHODS</b>A series of aryl-substituted pteridines were synthesized from 4, 6-diamino-5-nitrosopyrimidines by cyclization with 4-aminophenylacetonitriles. The antitumour activities were tested by MTT method.</p><p><b>RESULTS</b>Nine new compounds (I-III) were synthesized and their structures were characterized by EA, IR, 1HNMR and MS spectra. Compounds I-III showed antitumour activities in vitro.</p><p><b>CONCLUSION</b>Compounds I-III showed remarkable antitumour activities in vitro. No interaction was determined between the title compounds and calf thymus DNA. It indicated that these compounds possibly inhibit dihydrofolate reductase (DHFR) or other enzymes on which folic acid depends.</p>

Experimental chemotherapy against xenografts derived from multidrug resistant KBv200 cells and parental drug-sensitive KB cells in nude mice by annonaceous acetogenin 89-2 / 药学学报

<p><b>AIM</b>Annonaceous acetogenin 89-2 was obtained from atemoya plant. To investigate the effect of 89-2 on experimental chemotherapy against xenografts derived from multidrug resistant KBv200 cells and parental drug-sensitive KB cells.</p><p><b>METHODS</b>Cytotoxicity was determined by tetrazolium (MTT) assay. The models of KB and KBv200 xenografts in nude mice were established to investigate the effect of 89-2 on experimental chemotherapy against cancer in vivo. Mechanistic experiments were conducted to examine the function of P-gp by Fura 2-AM assay.</p><p><b>RESULTS</b>The compound 89-2 showed potent cytotoxicity in KBv200 and KB cells, and the mean IC50 of 89-2 to KBv200 and KB cells was 48.7 and 64.6 nmol.L-1, respectively. The IC50 of 89-2 to multidrug resistant (MDR) cells was similar to that to the parental drug-sensitive cells (P < 0.05). In the models of KBv200 and KB cell xenografts in nude mice, 89-2 (0.90 mg.kg-1, q2d x 6) exhibited 52.3% and 56.5% in inhibiting the growth of xenografts, respectively. The toxicity was endurable. The intracellular accumulation of Fura-2 in KBv200 cells increased to 1.66, 2.03, and 2.74-fold, respectively, by addition of 12.8, 64 and 320 nmol.L-1 of 89-2.</p><p><b>CONCLUSION</b>Both MDR KBv200 cells and parental drug-sensitive KB cells were sensitive to the treatment of 89-2 in vitro and in vivo. The mechanism of overcoming MDR was associated with the decrease of P-gp function MDR cells.</p>