Association of ABCB1 gene polymorphisms rs1128503, rs2032582, rs4148738 with anemia in patients receiving dabigatran after total knee arthroplasty / 中华创伤杂志(英文版)

PURPOSE@#Dabigatran is usually prescribed in recommended doses without monitoring of the blood coagulation for the prevention of venous thromboembolism after joint arthroplasty. ABCB1 is a key gene in the metabolism of dabigatran etexilate. Its allele variants are likely to play a pivotal role in the occurrence of hemorrhagic complications.@*METHODS@#The prospective study included 127 patients with primary knee osteoarthritis undergoing total knee arthroplasty. Patients with anemia and coagulation disorders, elevated transaminase and creatinine levels as well as already receiving anticoagulant and antiplatelet therapy were excluded from the study. The association of ABCB1 gene polymorphisms rs1128503, rs2032582, rs4148738 with anemia as the outcome of dabigatran therapy was evaluated by single-nucleotide polymorphism analysis with a real-time polymerase chain reaction assay and laboratory blood tests. The beta regression model was used to predict the effect of polymorphisms on the studied laboratory markers. The probability of the type 1 error (p) was less than 0.05 was considered statistically significant. BenjaminiHochberg was used to correct for significance levels in multiple hypothesis tests. All calculations were performed using Rprogramming language v3.6.3.@*RESULTS@#For all polymorphisms there was no association with the level of platelets, protein, creatinine, alanine transaminase, prothrombin, international normalized ratio, activated partial thromboplastin time and fibrinogen. Carriers of rs1128503 (TT) had a significant decrease of hematocrit (p = 0.001), red blood count and hemoglobin (p = 0.015) while receiving dabigatran therapy during the postoperative period compared to the CC, CT. Carriers of rs2032582 (TT) had a significant decrease of hematocrit (p = 0.001), red blood count and hemoglobin (p = 0.006) while receiving dabigatran therapy during the postoperative period compared to the GG, GT phenotypes. These differences were not observed in carriers of rs4148738.@*CONCLUSION@#It might be necessary to reconsider thromboprophylaxis with dabigatran in carriers of rs1128503 (TT) or rs2032582 (TT) polymorphisms in favor of other new oral anticoagulants. The long-term implication of these findings would be the reduction of bleeding complications after total joint arthroplasty.

Effects of hypoxia on the expression and function of P-gp in Caco-2 cells / 中南大学学报(医学版)

OBJECTIVES@#Hypoxia can alter the oral bioavailability of drugs, including various substrates (drugs) of P-glycoprotein (P-gp), suggesting that hypoxia may affect the function of P-gp in intestinal epithelial cells. Currently, Caco-2 monolayer model is the classic model for studying the function of intestinal epithelial P-gp. This study combines the Caco-2 monolayer model with hypoxia to investigate the effects of hypoxia on the expression and function of P-gp in Caco-2 cells, which helps to elucidate the mechanism of changes in drug transport on intestinal epithelial cells in high-altitude hypoxia environment.@*METHODS@#Normally cultured Caco-2 cells were cultured in 1% oxygen concentration for 24, 48, and 72 h, respectively. After the extraction of the membrane proteins, the levels of P-gp were measured by Western blotting. The hypoxia time, with the most significant change of P-gp expression, was selected as the subsequent study condition. After culturing Caco-2 cells in transwell cells for 21 days and establishing a Caco-2 monolayer model, they were divided into a normoxic control group and a hypoxic group. The normoxic control group was continuously cultured in normal condition for 72 h, while the hypoxic group was incubated for 72 h in 1% oxygen concentration. The integrity and polarability of Caco-2 cells monolayer were evaluated by transepithelial electrical resistance (TEER), apparent permeability (Papp) of lucifer yellow, the activity of alkaline phosphatase (AKP), and microvilli morphology and tight junction structure under transmission electron microscope. Then, the Papp of rhodamine 123 (Rh123), a kind of P-gp specific substrate, was detected and the efflux rate was calculated. The Caco-2 cell monolayer, culturing at plastic flasks, was incubated for 72 h in 1% oxygen concentration, the expression level of P-gp was detected.@*RESULTS@#P-gp was decreased in Caco-2 cells with 1% oxygen concentration, especially the duration of 72 h (P<0.01). In hypoxic group, the TEER of monolayer was more than 400 Ω·cm2, the Papp of lucifer yellow was less than 5×10-7 cm/s, and the ratio of AKP activity between apical side and basal side was greater than 3. The establishment of Caco-2 monolayer model was successful, and hypoxia treatment did not affect the integrity and polarization state of the model. Compared with the normoxic control group, the efflux rate of Rh123 was significantly reduced in Caco-2 cell monolayer of the hypoxic group (P<0.01). Hypoxia reduced the expression of P-gp in Caco-2 cell monolayer (P<0.01).@*CONCLUSIONS@#Hypoxia inhibits P-gp function in Caco-2 cells, which may be related to the decreased P-gp level.

Effect of hypoxia on HIF -1 α/MDR1/VEGF expression in gastric cancer cells treated with 5 -fluorouracil / 中南大学学报(医学版)

OBJECTIVES@#Fluorouracil chemotherapeutic drugs are the classic treatment drugs of gastric cancer. But the problem of drug resistance severely limits their clinical application. This study aims to investigate whether hypoxia microenvironment affects gastric cancer resistance to 5-fluorouracil (5-FU) and discuss the changes of gene and proteins directly related to drug resistance under hypoxia condition.@*METHODS@#Gastric cancer cells were treated with 5-FU in hypoxia/normoxic environment, and were divided into a Normoxic+5-FU group and a Hypoxia+5-FU group. The apoptosis assay was conducted by flow cytometry Annexin V/PI double staining. The real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the expression level of hypoxia inducible factor-1α (HIF-1α), multidrug resistance (MDR1) gene, P-glycoprotein (P-gp), and vascular endothelial growth factor (VEGF) which were related to 5-FU drug-resistance. We analyzed the effect of hypoxia on the treatment of gastric cancer with 5-FU.@*RESULTS@#Compared with the Normoxic+5-FU group, the apoptosis of gastric cancer cells treated with 5-FU in the Hypoxia+5-FU group was significantly reduced (P<0.05), and the expression of apoptosis promoter protein caspase 8 was also decreased. Compared with the the Normoxic+5-FU group, HIF-1α mRNA expression in the Hypoxia+5-FU group was significantly increased (P<0.05), and the mRNA and protein expression levels of MDR1, P-gp and VEGF were also significantly increased (all P<0.05). The increased expression of MDR1, P-gp and VEGF had the same trend with the expression of HIF-1α.@*CONCLUSIONS@#Hypoxia is a direct influencing factor in gastric cancer resistance to 5-FU chemotherapy. Improvement of the local hypoxia microenvironment of gastric cancer may be a new idea for overcoming the resistance to 5-FU in gastric cancer.

Association of SCN2A, ABCB1 and CYP2C19*3 with genetic susceptibility to major depressive disorder / 中华预防医学杂志

Objective: Due to genetic factors might increase the risk of depression, this study investigated the genetic risk factors of depression in Chinese Han population by analyzing the association between 13 candidate genes and depression. Methods: 439 depression patients and 464 healthy controls were included in this case-control study. Case group consisted of 158 males and 281 females, aged (29.84±14.91) years old, who were hospitalized in three departments of the affiliated Brain Hospital of Guangzhou Medical University including Affective Disorders Department, Adult Psychiatry Department and Geriatrics Department, from February 2020 to September 2021. The control group consisted of 196 males and 268 females, aged (30.65±12.63) years old. 20 loci of 13 candidate genes in all subjects were detected by MALDI-TOF mass spectrometry. Age difference was compared using the student's t-test, the distributions of gender and genotype were analyzed with Pearson's Chi-square test. The analyses of Hardy-Weinberg equilibrium, allele frequency and the genetic association of depression were conducted using the corresponding programs in PLINK software. Results: PLINK analysis showed that SCN2A rs17183814, ABCB1 rs1045642, CYP2C19*3 rs4986893 and NAT2*5A rs1799929 were associated with depression before Bonferroni correction (χ2=10.340, P=0.001; χ2=11.010, P=0.001; χ2=9.781, P=0.002; χ2=4.481, P=0.034). The frequencies of minor alleles of above loci in the control group were 12.07%, 43.64%, 2.59% and 3.88%, respectively. The frequencies of minor alleles of loci mentioned above in the case group were 17.43%, 35.99%, 5.47% and 6.04%, respectively. OR values were 1.538, 0.726, 2.178 and 1.592, respectively. After 1 000 000 permutation tests using Max(T) permutation procedure, the four loci were still statistically significant, the empirical P-value were 0.002, 0.001, 0.003 and 0.042, respectively. However, only three loci including SCN2A rs17183814, ABCB1 rs1045642 and CYP2C19 rs4986893 had statistical significance after Bonferroni correction, the adjusted P-value were 0.026, 0.018 and 0.035, respectively. Conclusion: SCN2A rs17183814, ABCB1 rs1045642 and CYP2C19*3 rs4986893 were associated with depression's susceptibility in Chinese Han population. The A allele of SCN2A rs17183814 and CYP2C19*3 rs4986893 were risk factors for depression, while the T allele of ABCB1 rs1045642 was a protective factor for depression.

Reversal of Drug Resistance in K562/ADM Cells Caused by RA and the Related Mechanisms / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of ursane triterpenoids 3β,19α-dihydroxyursu-12-ene-23,28-dicarboxylic acid (Rotundioic acid, RA) on the sensitivity of adriamycin-resistant K562 cells (K562/ADM Cell) anti-tumor drug, and to explore the effect and mechanism of RA on the multidrug resistance of K562/ADM cells.@*METHODS@#CCK-8 method was used to detect the effect of RA on the sensitivity of K562 cells and K562/ADM cells to anti-tumor drug. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect the expression level of mRNA and the protein in K562 and K562/ADM cells, and the effect of RA on the expression of MDR1 mRNA and P-gp in K562/ADM cells was also detected; Western blot was used to detect the expression of p-JNK, p-p38 and p-ERK1/2 in K562/ADM cells.@*RESULTS@#RA could increased the sensitivity of K562/ADM cells to adriamycin(the reversal factor was 1.61 times), the difference showed statistically significantly (P<0.05); the resistance factor of K562/ADM to ADM was 41.76 times. The expression of MDR1 mRNA in K562 cells was extremely low, and the protein product P-glycoprotein (P-gp) was almost not expressed; MDR1 mRNA and P-gp in K562/ADM cells were highly expressed; RA could down-regulate the expression levels of MDR1 and P-gp in K562/ADM cells. In addition, RA could upregulate the phosphorylation levels of p38 and ERK1/2 in K562/ADM cells, but it has no effect on the expression of p-JNK.@*CONCLUSION@#RA may participate in the regulation of MAPK signaling pathway by upregulating the expression levels of p-p38 and p-ERK1/2 in K562/ADM cells, and thus inhibit the transcription and translation levels of MDR1, and finally reverse the multidrug resistance of leukemia cells.

Is there a clinical pathological correlation of colorectal adenocarcinoma with the immunohistochemical expression of opn and abcb5? / Há correlação clínicopatológica do adenocarcinoma colorretal com a expressão imunoistoquímica do opn e abcb5?

ABSTRACT Background: Studies with biomarkers in TMA (tissue microarray) have been showing important results regarding its expression in colon cancer. Aim: Correlate the expression profile of the OPN and ABCB5 biomarkers with the epidemiological and clinicopathological characteristics of the patients, the impact on the progression of the disease and the death. Method: A total of 122 CRC patients who underwent surgical resection, immunomarking and their relationship with progression and death events were evaluated. Result: The average age was 61.9 (±13.4) years. The cases were distributed in 42 (35.9%) in the ascending/transverse colon, 31 (26.5%) in the sigmoid, 27 in the rectum (23.1%), 17 (14.5%) in the descending colon. Most patients had advanced disease (stages III and IV) in 74 cases (60.9%). There was a predominance of moderately differentiated tumors in 101 samples (82.8%); despite this, the poorly differentiated subtype proved to be an independent risk factor for death in 70%. Metastasis to the liver proved to be an independent risk factor for death in 75% (18/24), as well as patients with primary rectal tumors in 81.5% (22/27). Conclusion: The immunohistochemical expression of the OPN and ABCB5 markers was not associated with epidemiological and clinicopathological characteristics. Regarding the progression of disease and death, it was not possible to observe a correspondence relationship with the evaluated markers.

RESUMO Racional: Estudos com biomarcadores com TMA (tissue microarray) vêm demostrando resultados importantes em relação à expressão de biomarcadores em câncer de cólon. Objetivo: Correlacionar o perfil de expressão dos biomarcadores OPN e ABCB5 com as características epidemiológicas e clinicopatológicas dos pacientes, o impacto na progressão de doença e no evento óbito. Método: Foram avaliados 122 pacientes de CCR submetidos à ressecção cirúrgica e à imunomarcação e relação com os eventos progressão e óbito. Resultado: A média de idade encontrada foi de 61,9 (±13,4) anos. Os casos distribuíram-se em 42 (35,9%) no cólon ascendente/transverso, 31 (26,5%) no sigmoide, 27 no reto (23,1%), 17 (14,5%) no cólon descendente. A maioria dos pacientes apresentou doença avançada (estadio III e IV) em 74 casos (60,9%). Houve predomínio de tumor moderadamente diferenciado em 101 amostras (82,8%); apesar disso, o subtipo pouco diferenciado mostrou-se como fator de risco independente para óbito em 70% dos casos. Metástase para o fígado mostrou-se fator de risco independente para óbito em 75% dos casos (18/24), assim como pacientes com tumores primários de reto em 81,5% (22/27). Conclusão: A expressão imunoistoquímica dos marcadores OPN e ABCB5 não apresentou associação com as características epidemiológicas e clinicopatológicas. Em relação à progressão de doença e evento óbito, não se conseguiu observar relação de correspondência com os marcadores avaliados.

mRNA expression of MDR3 gene in the blood of preterm infants with parenteral nutrition-associated cholestasis / 中国当代儿科杂志

OBJECTIVE@#To study the association between the expression of the MDR3 gene and the pathogenesis of parenteral nutrition-associated cholestasis (PNAC) in preterm infants.@*METHODS@#Among the preterm infants who were admitted to the hospital from June 2011 to November 2017 and received parenteral nutrition for more than 14 days, 80 who did not develop PNAC were enrolled as non-PNAC group, and 76 who developed PNAC were enrolled as PNAC group. On days 1, 14, 30, 60 and 90 after birth, serum hepatobiliary biochemical parameters [alanine aminotransferase (ALT), total bilirubin (TBil), direct bilirubin (DBil), total bile acid (TBA) and gamma-glutamyl transpeptidase (γ-GT)], fibrosis indices [hyaluronic acid, laminin, procollagen III N-terminal peptide and type IV collagen] and clinical manifestations were observed. Real-time quantitative PCR was used to measure the mRNA expression of MDR3 in both groups, and the correlation between the mRNA expression of MDR3 and serum hepatobiliary biochemical parameters was analyzed.@*RESULTS@#In the PNAC group, serum levels of hepatobiliary biochemical parameters and fibrosis indices increased on day 14 after birth and reached the peak on day 30 after birth, followed by a reduction on day 60 after birth. On days 14, 30, 60 and 90 after birth, the PNAC group had significantly higher serum levels of hepatobiliary biochemical parameters and fibrosis indices than the non-PNAC group (P<0.05). The PNAC group had higher relative mRNA expression of MDR3 in peripheral blood cells than the non-PNAC group (P<0.05). In the PNAC group, the relative mRNA expression of MDR3 in peripheral blood cells was negatively correlated with serum levels of hepatobiliary biochemical parameters (ALT, TBil, DBil, TBA and γ-GT) (P<0.001).@*CONCLUSIONS@#High mRNA expression of MDR3 in preterm infants may be associated with the development of PNAC, and further studies are needed to identify the mechanism.

Wnt5a modulates vincristine resistance through PI3K/Akt/GSK3β signaling pathway in human ovarian carcinoma SKOV3/VCR cells / 生理学报

The aim of this study was to investigate the effect of Wnt5a on the vincristine (VCR) resistance in human ovarian carcinoma SKOV3 cells and its possible mechanism. The drug-resistant SKOV3/VCR cells were established by stepwise exposure to VCR, and then the SKOV3/VCR cells were stably transfected with specific shRNA interference plasmid vector targeting for Wnt5a. The mRNA expression level of Wnt5a was measured by RT-PCR. CCK-8 assay was used to detect the cell viability of SKOV3/VCR cells. The apoptosis was analyzed by flow cytometry. The protein expression levels of Wnt5a, MDR1, Survivin, β-catenin, Akt, p-Akt(S473), GSK3β and p-GSK3β(Ser9) were detected by Western blot. The result showed that SKOV3/VCR cells had significantly higher protein expression levels of Wnt5a, MDR1, Survivin and β-catenin, phosphorylation levels of Akt and GSK3β, and mRNA expression level of Wnt5a, compared with SKOV3 cells (P < 0.05). WNT5A gene silencing significantly increased the sensitivity of SKOV3/VCR cells to VCR, the IC of VCR being decreased from 38.412 to 9.283 mg/L (P < 0.05), synergistically enhanced VCR-induced apoptosis of SKOV3/VCR cells (P < 0.05), down-regulated the protein expression levels of MDR1, β-catenin and Survivin (P < 0.05), and inhibited phosphorylation of Akt and GSK3β (P < 0.05). Meanwhile, LY294002 (PI3K inhibitor) decreased the protein expression levels of MDR1, β-catenin and Survivin, as well as the phosphorylation levels of Akt and GSK3β in SKOV3/VCR cells (P < 0.05). These results suggest that WNT5A gene silencing reverses VCR resistance in SKOV3/VCR cells possibly through blocking the PI3K/Akt/GSK3β/β-catenin signaling pathway, and thus down-regulating the protein expression levels of MDR1 and Survivin.

Association of MDR1 gene polymorphisms with refractory epilepsy in children / 中华医学遗传学杂志

OBJECTIVE@#To assess the association of single nucleotide polymorphisms of multidrug resistance gene 1 (MDR1) with refractory epilepsy in children.@*METHODS@#Peripheral blood samples were collected from 200 children with epilepsy and 100 healthy controls. Genomic DNA was extracted and subjected to PCR amplification, agarose gel electrophoresis and target site sequencing. Genotypes of rs1922242, rs2235048, rs10808072, rs868755 and rs1202184 loci of the MDR1 gene were analyzed.@*RESULTS@#No significant difference was found in genotypic distribution and allelic frequencies of the rs1922242, rs2235048, rs10808072 and rs868755 loci between the drug-resistant and drug-sensitive groups. For the rs1202184 locus, a significant difference in genotypic distribution was found (P=0.008). No significant difference was found in the frequencies of various haplotypes between the two groups.@*CONCLUSION@#Genotypes of the rs1202184 locus of the MDR1 gene are associated with refractory epilepsy in children, for which the AA genotype plays a dominant role.

High Expression of Multidrug Resistance Gene-1 Can Aggravate Resistance to Methotrexate in Rheumatoid Arthritis Patients / 中国医学科学院学报

Objective To explore the role of multidrug resistance gene-1(MDR1)gene in methotrexate(MTX)resistance in patients with rheumatoid arthritis(RA).Methods Fibroblast-like synoviocytes(FLS)from RA patients were infected with recombinant adenovirus Ad-EGFP-MDR1 to obtain MDR1 over-expressed RA FLS.The transcription level of MDR1 gene and the expression level of its coding product P-glycoprotein(P-gp) rotein were detected by real-time PCR and Western blot analysis.The efflux function was verified by rhodamine 123 efflux assay.The resistance to MTX was detected by MTT assay.Results RA FLS were infected with recombinant adenovirus Ad-EGFP-MDR1;72 hours later,the particles size in MDR1 over-expressed RA FLS increased,the cell volume became larger,and the growth rate decreased.The transcription level of MDR1(1.4325±0.3924 0.0650±0.0070;=6.035,=0.004),the expression level of P-gp protein(1.8667±0.2857 0.9367±0.0551;=5.536,=0.005),and the ability of extracellular rhodamine 123(979.43±196.81 1680.06±147.04;=-4.940,=0.008) in MDR1 over-expressed RA FLS were significantly higher than those of negative virus control RA-FLS,and the survival rate of MDR1 over-expressed RA FLS was significantly increased at each concentration of MTX(<0.05).Conclusion The high expression of MDR1 can affect the efflux ability to MTX by up-regulating the expression of P-gp,thus enhancing the drug resistance to MTX in RA FLS.

Association between multidrug resistance-1 C3435T gene polymorphism and right ventricular dysfunction in patients with chronic obstructive pulmonary disease: cross-sectional study

ABSTRACT BACKGROUND: Right ventricular (RV) dysfunction may develop over the course of chronic obstructive pulmonary disease (COPD) and is an important predictor of morbidity and mortality. Polymorphism of the multidrug resistance-1 (MDR-1) gene has been correlated with worse clinical findings among patients with COPD. Our aim here was to investigate the relationship between MDR-1 C3435T gene polymorphism and RV dysfunction in COPD patients. DESIGN AND SETTING: This was a cross-sectional study investigating the relationship between RV dysfunction and genetic defects in COPD patients. METHODS: Forty-one consecutive patients diagnosed with COPD and hospitalized due to acute exacerbation were enrolled. Polymorphism was analyzed using the strip assay technique. RV parameters were evaluated, and RV dysfunction was identified via transthoracic echocardiography. Patients were categorized into three groups according to gene polymorphism: MDR-1 CC (wild type, n = 9), MDR-1 CT (heterozygote mutant, n = 21) or MDR-1 TT (homozygote mutant, n = 11). RESULTS: The study included 14 males and 27 females (mean age 65 ± 11 years). The mean systolic pulmonary artery pressure was 31.4 ± 8 mmHg in the wild-type group, 42.2 ± 12 mmHg in the heterozygote mutant group and 46.5±14 mmHg in the homozygote mutant group (P = 0.027). Presence of RV dilatation was significantly different among the three groups (33%, 71%, and 100%, respectively; P = 0.005). In multiple logistic regression analysis, MDR-1 C3435T gene polymorphism (OR = 9.000, P = 0.019) was an independent predictor of RV dysfunction after adjustment for potential confounders. CONCLUSION: MDR-1 C3435T gene polymorphism was associated with RV dysfunction in patients with COPD.

Reversal of multidrug resistance by icaritin in doxorubicin-resistant human osteosarcoma cells / 中国天然药物

Multidrug resistance (MDR) is one of the major obstacles in cancer chemotherapy. Our previous study has shown that icariin could reverse MDR in MG-63 doxorubicin-resistant (MG-63/DOX) cells. It is reported that icariin is usually metabolized to icariside II and icaritin. Herein, we investigated the effects of icariin, icariside II, and icaritin (ICT) on reversing MDR in MG-63/DOX cells. Among these compounds, ICT exhibited strongest effect and showed no obvious cytotoxicity effect on both MG-63 and MG-63/DOX cells ranging from 1 to 10 μmol·L. Furthermore, ICT increased accumulation of rhodamine 123 and 6-carboxyfluorescein diacetate and enhanced DOX-induced apoptosis in MG-63/DOX cells in a dose-dependent manner. Further studies demonstrated that ICT decreased the mRNA and protein levels of multidrug resistance protein 1 (MDR1) and multidrug resistance-associated protein 1 (MRP1). We also verified that blockade of STAT3 phosphorylation was involved in the reversal effect of multidrug resistance in MG-63/DOX cells. Taken together, these results indicated that ICT may be a potential candidate in chemotherapy for osteosarcoma.

Reversal of multidrug resistance by icaritin in doxorubicin-resistant human osteosarcoma cells / 中国天然药物

Multidrug resistance (MDR) is one of the major obstacles in cancer chemotherapy. Our previous study has shown that icariin could reverse MDR in MG-63 doxorubicin-resistant (MG-63/DOX) cells. It is reported that icariin is usually metabolized to icariside II and icaritin. Herein, we investigated the effects of icariin, icariside II, and icaritin (ICT) on reversing MDR in MG-63/DOX cells. Among these compounds, ICT exhibited strongest effect and showed no obvious cytotoxicity effect on both MG-63 and MG-63/DOX cells ranging from 1 to 10 μmol·L. Furthermore, ICT increased accumulation of rhodamine 123 and 6-carboxyfluorescein diacetate and enhanced DOX-induced apoptosis in MG-63/DOX cells in a dose-dependent manner. Further studies demonstrated that ICT decreased the mRNA and protein levels of multidrug resistance protein 1 (MDR1) and multidrug resistance-associated protein 1 (MRP1). We also verified that blockade of STAT3 phosphorylation was involved in the reversal effect of multidrug resistance in MG-63/DOX cells. Taken together, these results indicated that ICT may be a potential candidate in chemotherapy for osteosarcoma.

Relation between single Nucleotide Polymorphisms of CYP3A5 Gene and MDR1 Gene Loci and Risk of CML Cytogenetic Relapse / 中国实验血液学杂志

OBJECTIVE@#To analyze the relation between the signle nucleotide polymorphisms (SNP) of CYP3A5 gene and MDR1 gene loci and the risk of cytogenetic relapse in chronic myeloid leukemia (CML).@*METHODS@#The clinical data of 90 patients with CML treated with imatinib in our hospital were collected.The patients were divided into 2 groups: non-relapse and relapse according to relapse and non-relapse, then the relation between the SNP of CYP3A5 gene and MRD1 gene loci and the risk of cytogenetic relapse in CML patients.@*RESULTS@#The grouping result showed that the patients with non cytogenetic relapse accounted for 41 cases those were enrolled in non-relapse group, and patient-with cytogenetic relapse accounted for 49 cases those were enrolled in relapse group. The follow-up time was 36 months. The detection showed that the incidence of cytogenetic relapse in the patients with CC genotype was significantly higher than that in the patients with TT+CT genotype of C3435T and C1236T at MDR1 gene loci (P<0.05).Compared with the patients with CT+CC genotype in C3435T locus of MDR1 gene, the rate of cytogenetic relapse in the patients with TT genotype decreased significantly (P<0.05). Compared with patients with CT+CC phemotype of C3435T in MDR1 gene locus, the non-relapse survival time of TT genotypes was significantly prolonged (P<0.05). Compared with non-relapse group, the incidence of neutropenia (29.27% vs 71.43%) and blood toxicity (39.02% vs 61.22%) in the relapse group increased significantly (P<0.05). The imatinib dose (OR=2 95, 95% CI:1.37~7.76) and the C3435T genotype in MDR1 genes (OR=0.09, 95% CI:0.05~0.72) were the factors affecting the cytogenetic relapse of the patients with CML (both P<0.05).@*CONCLUSION@#The therapeutic dose of imatinib and the C3435T and C1236T genotypes in MDR1 gene have a certain effect on the cytogenetic relapse of CML patients. C3435T genotypes in the.MDR1 gene showed a certain predictive value for evaluating the risk of cytogenetic relapse, which can be used as a clinical biomarker.

Decreased platelet responsiveness to clopidogrel correlates with CYP2C19 and PON1 polymorphisms in atherosclerotic patients

Clopidogrel and aspirin are the most commonly used medications worldwide for dual antiplatelet therapy after percutaneous coronary intervention. However, clopidogrel hyporesponsiveness related to gene polymorphisms is a concern. Populations with higher degrees of genetic admixture may have increased prevalence of clopidogrel hyporesponsiveness. To assess this, we genotyped CYP2C19, ABCB1, and PON1 in 187 patients who underwent percutaneous coronary intervention. Race was self-defined by patients. We also performed light transmission aggregometry with adenosine diphosphate (ADP) and arachidonic acid during dual antiplatelet therapy. We found a significant difference for presence of the CYP2C19*2 polymorphism between white and non-white patients. Although 7% of patients had platelet resistance to clopidogrel, this did not correlate with any of the tested genetic polymorphisms. We did not find platelet resistance to aspirin in this cohort. Multivariate analysis showed that patients with PON1 and CYP2C19 polymorphisms had higher light transmission after ADP aggregometry than patients with native alleles. There was no preponderance of any race in patients with higher light transmission aggregometry. In brief, PON1 and CYP2C19 polymorphisms were associated with lower clopidogrel responsiveness in this sample. Despite differences in CYP2C19 polymorphisms across white and non-white patients, genetic admixture by itself was not able to identify clopidogrel hyporesponsiveness.

P-glycoprotein expression in oral lichen planus

Abstract: Oral lichen planus (OLP) is a stress induced inflammatory condition with malignant potency. The mdr1 (multidrug resistance) is a stress gene overexpressed in cancerous conditions and its translated form, the p-glycoprotein efflux transporter is usually overexpressed with chemotherapy, leading to chemoresistance. OLP, a lesion with carcinogenic potency, is broadly classified into the asymptomatic reticular form and the aggressive erosive form. The objective of the study was to verify the expression level of p-glycoprotein in antifungal-treated and untreated reticular OLP, in untreated erosive OLP and erosive OLP patients treated with corticosteroid. Semi-quantitative reverse transcriptase polymerase chain reaction (SQ-RTPCR) and ELISA were performed on biopsy tissue samples to evaluate the mdr1 mRNA and protein expression of p-glycoprotein, respectively. The present study shows for the first time that mdr1 mRNA as well as its translated form p-glycoprotein are overexpressed in OLP subjects compared to healthy individuals. This overexpression is significantly higher in erosive than in reticular OLP patients, further confirming that the erosive form has higher risk for multidrug resistance. A higher expression is also observed in corticosteroid-treated erosive cases than similar untreated ones. The gradation of expression is in conformity with severity of the disease.

MiR-145 inhibits drug resistance to Oxaliplatin in colorectal cancer cells through regulating G protein coupled receptor 98 / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To predict and identify the target gene of miR-145, and to explore the underlying mechanism of the inhibition of miR-145 on drug resistance to Oxaliplatin (L-OHP) in human colorectal cancer cells.</p><p><b>METHODS</b>L-OHP-resistant human colorectal cancer cell line (HCT116/L-OHP) was established in vitro by exposing to increased concentrations of L-OHP in cell culture medium. MiR-145-mimics and its negative control (NC-miRNA) were transfected into HCT116/L-OHP cells using liposome to establish HCT116/L-OHPover-expressing miR-145 and HCT116/L-OHP. The target genes of miR-145 were predicted by bioinformatic analysis, and validated by dual luciferase activity assay. After determination of G protein coupled receptor 98(GPR98) as target gene, corresponding plasmids were constructed and transfected to establish HCT116/L-OHPover-expressing GPR98 and HCT116/L-OHP. HCT116/L-OHP cells over-expressing both GPR98 and miR-145 (HCT116/L-OHP) were acquired through modification of the binding sites of GPR98 cDNA with miR-145. CCK-8 assay was used to assess the proliferation (A value) and sensitivity to L-OHP (the lower the IC50, the stronger the sensitivity) in HCT116/L-OHP cells. Real-time quantitative PCR was used to measure the mRNA expression of miR-145 and GPR98. Western blot was used to examine the protein expression of GPR98 and drug-resistant associated protein, such as P-glycoprotein (gp), multiple drug-resistance protein 1(MRP1), cancer-inhibition gene PTEN.</p><p><b>RESULTS</b>HCT116/L-OHP cell line was successfully established with ICof (42.34±1.05) mg/L and miR-145 mRNA expression of 0.27±0.04, which was higher than (9.81±0.95) mg/L (t=39.784, P=0.000) and lower than 1.00±0.09 (t=13.021, P=0.000) in HCT116 cells. Based on HCT116/L-OHP cells, HCT116/L-OHPcells were established successfully, with relative miR-145 expression of 10.01±1.05, which was higher than 1.06±0.14 in HCT116/L-OHPand 1.00±0.16 in HCT116/L-OHP (F=161.797, P=0.000). GPR98 was identified to be the target gene of miR-145. The relative mRNA and protein expressions of GPR98 in HCT116/L-OHPcells were 8.48±0.46 and 1.71±0.09, respectively, which were higher than those in HCT116/L-OHP(mRNA: 3.65±0.40, protein: 1.21±0.10) and HCT116/L-OHP (mRNA: 3.49±0.35, protein: 1.22±0.08; all P<0.05). The A value was 1.31±0.10, and the relative protein expressions of P-gp and MRP1 were 1.53±0.18 and 1.49±0.20 in HCT116/L-OHPcells, which were higher than those in HCT116/L-OHP (A value: 0.82±0.08, relative protein expression: 1.00±0.06 and 1.21±0.13, all P<0.05). The A value was 0.89±0.08, and the relative protein expressions of P-gp and MRP were 1.02±0.24 and 1.38±0.25 in HCT116/L-OHPcells, which were higher than those in HCT116/L-OHP(A value: 0.20±0.05, relative protein expression: 0.20±0.07, 0.55±0.10, all P<0.05). The relative protein expression of PTEN in HCT116/L-OHPcells was 0.12±0.03, which was lower than 1.25±0.14 in HCT116/L-OHP cells(P<0.05). In addition, relative protein expressions of P-gp and MRP1 were 1.02±0.24 and 1.38±0.25 in HCT116/L-OHPcells, which were higher than those in HCT116/L-OHPcells (0.20±0.07 and 0.55±0.10), while PTEN expression in HCT116/L-OHPcells was lower as compared to HCT116/L-OHPcells (1.41±0.16 vs. 1.98±0.13, P<0.05).</p><p><b>CONCLUSION</b>MiR-145 inhibits drug resistance to L-OHP of HCT116 cells through suppressing the expression of target gene GPR98.</p>

Expression and clinical pathological implications of carbonic anhydrase 9 and P glycoprotein in laryngeal squamous cell carcinoma / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To identify the difference of CA IX and P-gp expression level between laryngeal squamous cell carcinoma (LSCC) and benign tissues, evaluate the relationship of these two proteins in LSCC, and their correlation with clinical and pathological features.@*METHOD@#Immunohistochemical detection of CA IX and P-gp were performed in 47 cases of LSCC and 20 cases of vocal cord polyps.@*RESULT@#Overexpression of CA IX and P-gp both in LSCC and in vocal cord polyp (P < 0.05) were confirmed, with a correlation between the two proteins in LSCC (r = 0.324, P < 0.05). The expression of CA IX was related to clinical staging and lymph node metastasis in LSCC (P < 0.05). While P-gp was related to clinical staging and histological grading in LSCC (P < 0.05).@*CONCLUSION@#The overexpression of CA IX and P-gp may play a role in LSCC progression.

Cytological Study in vitro on Co-delivery of siRNA and Paclitaxel within Solid Lipid Nanoparticles to Overcome Multidrug Resistance in Tumors / 生物医学工程学杂志

Multidrug resistance (MDR) remains the major obstacle to the success of clinical cancer chemotherapy. P-glycoprotein (P-gp), encoded by the MDR1, is an important part with complex mechanisms associated with the MDR. In order to overcome the MDR of tumors, we in the present experimental design incorporated small interfering RNA (siRNA) targeting MDR1 gene and anticancer drug paclitaxel (PTX) into the solid lipid nanoparticles (SLNs) to achieve the combinational therapeutic effects of genetherapy and chemotherapy. In this study, siRNA-PTX-SLNs were successfully prepared. The cytotoxicity of blank SLNs and siRNA-PTX-SLNs in MCF-7 cells and MCF-7/ADR cells were detected by MTT; and the uptake efficiency of PTX in MCF-7/ADR cells were detected via HPLC method; quantitative real-time PCR and flow cytometry were performed to investigate the silencing effect of siRNA-PTX- SLNs on MDR1 gene in MCF-7/ADR cells. The results showed that PTX loaded SLNs could significantly inhibit the growth of tumor cells, and more importantly, the MDR tumor cells treated with siRNA-PTX-SLNs showed the lowest viability. HPLC study showed that SLNs could enhance the cellular uptake for PTX. Meanwhile, siRNA delivered by SLNs significantly decreased the P-gp expression in MDR tumor cells, thus increased the cellular accumulation of rhodamine123 as a P-gp substrate. In conclusion, the MDR1 gene could be silenced by siRNA-PTX-SLNs, which could promote the growth inhibition efficiency of PTX on tumor cells, leading to synergetic effect on MDR tumor therapy.

Effect of Siwu decoction on function and expression of P-glycoprotein in Caco-2 cells / 中国中药杂志

To study the effect of Siwu decoction on the function and expression of P-glycoprotein (P-gp) in Caco-2 cells. The Real-time quantitative poly-merase chain reaction (Q-PCR) was used to analyze the mRNA expression of MDR1 gene in Caco-2 cells. Flow cytometer was used to study the effect of Siwu decoction on the uptake of Rhodamine 123 in Caco-2 cells, in order to evaluate the efflux function of P-gp. Western blotting method was used to detect the effect of Siwu decoction on the P-gp protein expression of Caco-2 cells. Compared with the blank control group, after Caco-2 incubation with Siwu decoction at concentrations of 3.3, 5.0, 10.0 g x L(-1) for 24, 48, 72 h, the mRNA expression of MDR1 was up-regulated, suggesting the effect of Siwu decoction in inducing the expression of MDR1. After the administration with Siwu decoction in Caco-2 cells for 48 h, the uptake of Rhodamine 123 in Caco-2 cells decreased by respectively 16.6%, 22.1% (P < 0.05) and 45.4% (P < 0.01), indicating that the long-term administration of Siwu decoction can enhance the P-gp efflux function of Caco-2 cells. After the incubation of Caco-2 cells with Siwu decoction for 48 h, the P-gp protein expression on Caco-2 cell emebranes, demonstrating the effect of Siwu decoction in inducing the protein expression of P-gp.