<b>BACKGROUNDb>Proteasome subunits (PSMB) and transporter associated with antigen processing (TAP) loci are located in the human leukocyte antigen (HLA) Class II region play important roles in immune response and protein degradation in neurodegenerative diseases. This study aimed to explore the association between single nucleotide polymorphisms (SNPs) of PSMB and TAP and Parkinson's disease (PD).

<b>METHODSb>A case-control study was conducted by genotyping SNPs in PSMB8, PSMB9, TAP1, and TAP2 genes in the Chinese population. Subjects included 542 sporadic patients with PD and 674 healthy controls. Nine identified SNPs in PSMB8, PSMB9, TAP1, and TAP2 were genotyped through SNaPshot testing.

<b>RESULTSb>The stratified analysis of rs17587 was specially performed on gender. Data revealed that female patients carry a higher frequency of rs17587-G/G versus (A/A + G/A) compared with controls. But there was no significant difference with respect to the genotypic frequencies of the SNPs in PSMB8, TAP1, and TAP2 loci in PD patients.

<b>CONCLUSIONb>Chinese females carrying the rs17587-G/G genotype in PSMB9 may increase a higher risk for PD, but no linkage was found between other SNPs in HLA Class II region and PD.

ATP-Binding Cassette Sub-Family B Member 2 ; genetics ; ATP-Binding Cassette, Sub-Family B, Member 3 ; genetics ; Adult ; Aged ; Antigen Presentation ; Case-Control Studies ; Cysteine Endopeptidases ; genetics ; Female ; Humans ; Male ; Middle Aged ; Parkinson Disease ; genetics ; immunology ; Polymorphism, Single Nucleotide ; Proteasome Endopeptidase Complex ; genetics

<b>OBJECTIVEb>To study the molecular mechanism of cisplatin to enhance the ability of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in reversing multidrug resistance in vincristine-resistant human gastric cancer SGC7901/VCR cells.

<b>METHODSb>MTT assay was used to measure the 50% inhibiting concentration (IC₅₀) and cell survival in SGC7901 and SGC7901/VCR cells after different treatments. SGC7901/VCR cells were treated with different concentrations of DDP, different concentrations of TRAIL alone or in combination, and then the mRNA and protein levels of several genes were determined by RT-PCR, RT-qPCR and Western-blot analysis. After targeted silencing with specific siRNA and transfection of recombinant plasmid c-myc into the SGC7901/VCR cells, the mRNA and protein levels of DR4, DR5 and c-myc were determined by RT-PCR and Western-blot analysis.

<b>RESULTSb>After combined treatment with TRAIL and DDP of the SGC7901/VCR cells, the IC₅₀ of VCR, DDP, ADM, and 5-Fu treatment was significantly decreased compared with the control group or TRAIL-treated group (P < 0.05). After treatment with 0, 10, 50 ng/ml TRAIL in combination with 0.4 µg/ml DDP, the SGC7901/VCR cells showed significantly higher activation of caspase 3, down-regulation of DNA-PKcs/Akt/GSK-3β signaling pathway, and higher inhibition of MDR1(P-gp) and MRP1 than those treated with TRAIL alone (P < 0.01 for all). The mRNA and protein levels of DR4, DR5, c-myc were significantly decreased after silencing c-myc with specific siRNA in the SGC7901/VCR cells (P < 0.01 for all), and were significantly increased after transfection of recombinant plasmid c-myc into the SGC7901/VCR cells (P < 0.01 foe all). After the treatment with 10 ng/ml TRAIL, 0.25 µg/ml DDP + 10 ng/ml TRAIL and 0.5 µg/ml DDP + 10 ng/ml TRAIL, the relative expression level of c-myc protein in the SGC7901/VCR cells was 0.314 ± 0.012, 0.735 ± 0.026, and 0.876 ± 0.028, respectively, and the relative expression of cytochrome C was 0.339 ± 0.036, 0.593 ± 0.020 and 0.735 ± 0.031, respectively, and the relative expression levels of DR4, DR5, active-caspase 3 and active-caspase 9 in the SGC7901/VCR cells were also increased along with increasing DDP concentrations.

<b>CONCLUSIONSb>The activation of DNA-PKcs/Akt/GSK-3β signaling pathway and high expression of MDR1 and MRP1 play an important role in the multi-drug resistance properties of SGC7901/VCR cells. After combining with TRAIL, DDP can enhance the expression of DR4 and DR5 through up-regulating c-myc and enhancing the activation of caspase 3 and caspase 9 by facilitating mitochondrial release of cytochrome C. It may be an important molecular mechanism of DDP-induced sensitization of TRAIL to reverse the multidrug resistancein SGC7901/VCR cells.

ATP-Binding Cassette, Sub-Family B, Member 1 ; metabolism ; Antineoplastic Agents ; administration & dosage ; pharmacology ; Antineoplastic Combined Chemotherapy Protocols ; administration & dosage ; pharmacology ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Cell Line, Tumor ; Cisplatin ; administration & dosage ; pharmacology ; Down-Regulation ; Drug Resistance, Multiple ; drug effects ; Drug Resistance, Neoplasm ; drug effects ; Fluorouracil ; administration & dosage ; pharmacology ; Formazans ; Genes, myc ; Glycogen Synthase Kinase 3 ; metabolism ; Glycogen Synthase Kinase 3 beta ; Humans ; Inhibitory Concentration 50 ; Multidrug Resistance-Associated Proteins ; metabolism ; Neoplasm Proteins ; metabolism ; Plasmids ; Proto-Oncogene Proteins c-myc ; metabolism ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; pharmacology ; Receptors, TNF-Related Apoptosis-Inducing Ligand ; metabolism ; Stomach Neoplasms ; drug therapy ; pathology ; TNF-Related Apoptosis-Inducing Ligand ; administration & dosage ; pharmacology ; Tetrazolium Salts ; Transfection ; methods

Cryptotanshinone (CPT), a lipid soluble active compound in Salvia miltiorrhiza, has a significant inhibitory effect on multiple malignant tumors, e. g. chronic myeloid leukemia (CML) cells and can effectively enhance imatinib's chemotherapeutic effect. However, its functional molecular mechanism remained unclear. In this experiment, the authors conducted a systematic study on the effect of CPT on the imatinib sensitivity and P-glycoprotein (P-gp) expression in CML cells by using CML cells K562 and imatinib persister K562-R. The MTT assays were performed to determine CPT's impact on the inhibitory effect of imatinib. Annexin V-FITC/PI staining analysis was used to detect the changes in the cell apoptosis rate. The active changes in apoptosis regulatory proteins Caspase-3, Caspase-9 and PARP were determined by Western blot. After the cells were pretreated with the gradient concentration of CPT, the expression of P-gp was analyzed by Western blot and flow cytometry. The changes in intracellular concentrations of imatinib were determined by HPLC analysis. The results indicated that the pretreatment with CPT significantly increased the proliferation inhibiting and apoptosis inducing effects of imatinib on K562 and K562-R cells as well as the degradation product expression of pro-apoptotic proteins Caspase-3, Caspase-9 and PARP, with a significant difference with the control group (P < 0.01). However, CPT showed no impact on the P-gp expression in CML cells and the intracellular concentrations of imatinib. In summary, the findings suggested that CPT enhanced the sensitivity of CML cells to imatinib. Its mechanism is not dependent on the inhibition in P-gp expression and the increase in intracellular drug concentration.
ATP-Binding Cassette, Sub-Family B, Member 1 ; genetics ; metabolism ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Caspase 3 ; genetics ; metabolism ; Caspase 9 ; genetics ; metabolism ; Drug Resistance, Neoplasm ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Imatinib Mesylate ; pharmacology ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; genetics ; metabolism ; physiopathology ; Phenanthrenes ; pharmacology

<b>OBJECTIVEb>To explore the relationship between CD133(+) subsets cells in human gastric cancer (GC) and molecules of drug resistance and their sensitivity to 5-FU.

<b>METHODSb>Three gastric cancer cell lines therein KATO-III(, SGC7901 and MKN45 were sorted by immunomagnetic beads cell sorting method. Then above cell lines were further divided into un-sorted GC cells, CD133(+) subgroup and CD133(-) subgroup. The expressions of CD133, P-gp, Bax and Bcl-2 were determined by RT-PCR, Western blot and immunoflurescence. Meanwhile, the sensitivity to 5-FU of three subgroups was detected by CCK-8 Kit. The apoptosis induced by 5-FU in three subgroups was determined by Hoechst 33258.

<b>RESULTSb>Expressions of CD133 in three CD133(+) subgroups were significantly higher than those in un-sorted GC cells and CD133(-) subgroup (all P<0.05). Expressions of P-gp and Bcl-2 in the three GC cell lines were different (all P<0.05). There were significant differences of expressions of P-gp, Bcl-2 and Bax among CD133(+) cells, un-sorted GC cells and CD133(-) cells (all P<0.05). CCK-8 detection showed that CD133(-) subgroup of MKN45 GC cell line was more sensitive than CD133(+) cells to 5-FU (P<0.05). Hoechst 33258 staining showed that there were more apoptotic cells in CD133(-) subgroup as compared to other two subgroups, and the least apoptotic cells were observed in CD133(+) subgroup of MKN45 GC cell line (P<0.05). CD133 sirna was transfected into MKN45 GC cell line and could down-regulate the expressions of CD133, P-gp, Bcl-2 and p-Akt, while the expression of Bax increased (all P<0.05).

<b>CONCLUSIONSb>CD133 may contribute to the resistance of GC cells to chemotherapy drug through P-gp, Bcl-2 and Bax. PI3K/Akt signal pathway may be involved in this process.

AC133 Antigen ; ATP-Binding Cassette, Sub-Family B, Member 1 ; Antigens, CD ; metabolism ; Antineoplastic Agents ; pharmacology ; Apoptosis ; Cell Line, Tumor ; Drug Resistance, Neoplasm ; Fluorouracil ; Glycoproteins ; metabolism ; Humans ; Peptides ; metabolism ; Phosphatidylinositol 3-Kinases ; Proto-Oncogene Proteins c-akt ; RNA, Small Interfering ; Stomach Neoplasms ; drug therapy ; metabolism ; pathology ; bcl-2-Associated X Protein

<b>OBJECTIVEb>To assess the association between single nucleotide polymorphisms (SNPs) of PSMB8, PSMB9 and TAP2 genes and rheumatoid arthritis (RA) in ethnic Han Chinese from Yunnan.

<b>METHODSb>A case-control study was carried out using 177 RA patients and 288 healthy controls. Genotypes of rs2071543, rs55745125 and rs138635403 loci of PSMB8 gene, and rs17587 locus of PSMB9 gene were determined with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). And a polymerase chain reaction amplification refractory mutation system (ARMS-PCR) was used for typing rs2228396 locus of TAP2 gene. Genotypic and allelic frequencies were calculated. An Epi Info 7 software was used to calculate the Odds Ratio (OR) of above SNPs between the two groups.

<b>RESULTSb>Allelic and genotypic frequencies of rs138635403 and rs17587 loci have differed significantly between the two groups (P<0.05). The frequency of GG genotype for rs17587 locus was also higher in the RA group (0.672) compared with control group (0.524) (OR=1.862, 95%CI: 1.261-2.749).

<b>CONCLUSIONb>Genetic polymorphisms of rs17587 appeared to be associated with RA in ethnic Han Chinese from Yunnan.

ATP-Binding Cassette Transporters ; genetics ; ATP-Binding Cassette, Sub-Family B, Member 3 ; Arthritis, Rheumatoid ; genetics ; Case-Control Studies ; China ; ethnology ; Cysteine Endopeptidases ; genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Polymorphism, Single Nucleotide ; Proteasome Endopeptidase Complex ; genetics

<b>OBJECTIVEb>To establish a bcr-abl(+) cell line resistance to nilotinib, and to investigate the possible mechanisms of resistance.

<b>METHODSb>K562 cells were treated with gradually increasing concentrations of nilotinib to generate resistance cell line K562-RN. The folder of drug-resistance was evaluated by MTT assay. Cells apoptosis rate was detected by flow cytometry, the mRNA level of bcr-abl fusion gene by FISH, and the expression of apoptosis relative gene mRNA and protein (such as bcr-abl, HO-1, mdr1, Bcl-2 and caspase-3) by RQ-PCR and western blot.

<b>RESULTSb>The resistant cell line K562-RN was successfully established, with 2.01 fold resistant to nilotinib compared with K562 cell line \[the IC(50) value of nilotinib to K562 and K562-RN were (12.320 ± 1.720) µmol/L and (24.742 ± 2.310) µmol/L, respectively\]. It also had the cross resistance to adriamycin, homoharringtonine, etoposide and imatinib. Treated with different concentrations of nilotinib, cell apoptosis rate of K562-RN was significantly lower than that of K562 cells. The rate of bcr-abl gene positive cells was 92% in K562-RN by FISH assay. The mRNA and protein levels of bcr-abl, HO-1 and mdr1 expression up-regulated in K562-RN cells, while those of caspase-3 expression down-regulated, being significantly statistical difference when compared with K562 cells (P < 0.05).

<b>CONCLUSIONb>Human leukemic cell line resistance to nilotinib, K562-RN is established successfully by gradually increasing concentrations of drug. The mechanisms of resistance in K562-RN is probably associated with increasing expression of bcr-abl, HO-1, mdr1 and decreasing expression of caspase-3 mRNA and protein levels.

ATP Binding Cassette Transporter, Sub-Family B ; ATP-Binding Cassette, Sub-Family B, Member 1 ; metabolism ; Caspase 3 ; metabolism ; Drug Resistance, Neoplasm ; Fusion Proteins, bcr-abl ; metabolism ; Gene Expression Regulation, Leukemic ; Heme Oxygenase-1 ; metabolism ; Humans ; K562 Cells ; drug effects ; Pyrimidines ; pharmacology

<b>OBJECTIVEb>To study the relationship between TAP (transporter associated with antigen processing) gene promoter regional methylation level and cervical lesions with HPV infection in Uyghur women.

<b>METHODSb>A specialized software was used to design specific primers of CpG island fragments of TAP1 and TAP2 gene promoter for PCR amplification, bisulfitemodified SiHa cancer cell DNA for PCR amplification, cloning and sequencing analysis to obtain the relevant information on the gene base sequence methylation of CpG sites. Seventy-eight fresh cervical tissue samples from Uyghur women with cervicitis (number = 15), cervical intraepithelial neoplasia (CIN, number = 30) and cervical squamous cell carcinoma (number = 33) were collected. The methylation level of TAP1 and TAP2 gene promoter regions was detected using MassArray DNA technology. HPV infection status was determined by HPV gene chips. The relationship between CpG-island methylation of gene promoter regions and HPV infection was then analyzed.

<b>RESULTSb>Each TAP1 and TAP2 gene corresponding target fragment contained 23 and 8 CpG sites. There were 5 and 8 CpG sites methylation occurred in SiHa cervical cancer cells genomic DNA respectively. The TAP1 methylation level increased steadily with the severity of cervical lesions. The methylation levels in cervical squamous cell carcinoma and CIN (0.048 ± 0.039 and 0.037 ± 0.026, respectively) were higher than that of normal cervical tissue (0.035 ± 0.029, P < 0.05). Although TAP2 gene methylation level also demonstrated similar changes, the difference however was not statistically significant (P > 0.05). HPV gene chip detected 13 HPV genotypes, with HPV16 infection rate being 66.7% (52/78). The methylated proportion of TAP1 positively correlated with HPV16 infection (χ(2) = 6.08, P = 0.039).

<b>CONCLUSIONb>TAP1 methylation is a remarkable phenomenon occurring in a range of cervical lesions and significantly associated with cervical HPV infection.

ATP-Binding Cassette Sub-Family B Member 2 ; ATP-Binding Cassette Transporters ; genetics ; ATP-Binding Cassette, Sub-Family B, Member 3 ; Adult ; Aged ; Asian Continental Ancestry Group ; genetics ; Carcinoma, Squamous Cell ; genetics ; virology ; Cervical Intraepithelial Neoplasia ; genetics ; virology ; CpG Islands ; genetics ; DNA Methylation ; Female ; Human papillomavirus 16 ; Humans ; Middle Aged ; Papillomavirus Infections ; Promoter Regions, Genetic ; Uterine Cervical Neoplasms ; genetics ; virology ; Uterine Cervicitis ; genetics ; virology

This study was purposed to explore the effects of hyperbaric oxygen (HBO) combined with adriamycin (ADM) on inducing apoptosis of multidrug resistant cells line K562/A02. The cell apoptosis and expression of caspase-3 activity were analyzed by flow cytometry and transmission electron microscopy; the expression levels of HIF-1α, BCL-2 and BAX mRNA were detected by quantitative real time PCR; the caspase 8 activity was determined by using caspase 8 kit; the expression level of P-gp was detected by Western blot. The results showed that the apoptosis rate of K562/A02 cells in combination group (0.2 MPa HBO + ADM) was higher than that in ADM group [(47.36 ± 3.87) % vs (28.51 ± 1.09) %], the difference was statistical significant (p < 0.05); the expression levels of HIF-1α mRNA, P-gp and BCL-2 in combination group were lower than those in ADM group, there were significant differences (p < 0.05); the activities of BAX, caspase 3 and caspase 8 proteins in combination group were higher than those in ADM group, the difference was statistical significant (p < 0.05). It is concluded that 0.2 MPa HBO combined with ADM can reverse the drug-resistance of K562/A02 cells to ADM, enhance the apoptosis rate of cells. The molecular mechanism may be related with down-regulation of P-gp and BCL-2 expression, and up-regulation of caspase-3 and caspase-8 activities by HIF-1α.
ATP-Binding Cassette, Sub-Family B, Member 1 ; metabolism ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Doxorubicin ; pharmacology ; Drug Resistance, Multiple ; drug effects ; Drug Resistance, Neoplasm ; drug effects ; Gene Expression Regulation, Leukemic ; Humans ; Hyperbaric Oxygenation ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; K562 Cells ; Proto-Oncogene Proteins c-bcl-2 ; metabolism

This study is to investigate the antitumor activity of CIP-36 on multidrug resistant human oral squamous carcinoma cell line (KBV200 cells) in vitro and the possible anticancer mechanisms. MTT assay, Hoechst fluorescein stain, RT-PCR and immunohistochemistry were carried out on KBV200 and KB cells. The growth of many tumor cells was obviously inhibited by CIP-36, especially the multidrug resistant cells KBV200. Obvious apoptosis could be observed in the Hoechst 33342 staining experiments. The results of RT-PCR showed that the levels of p53, p21, caspase-3 and bax mRNA increased, and meanwhile the expression of mdr-1 and bcl-2 mRNA decreased in a dose-dependent manner. The data were significantly different from that of vehicle. The expression of P-gp significantly decreased with the increasing dosage of CIP-36 examined by immunohistochemistry. It can be concluded that CIP-36 could change resistance-related genes and proteins to overcome multidrug resistance in the KBV200 cell line.
ATP Binding Cassette Transporter, Sub-Family B ; ATP-Binding Cassette, Sub-Family B, Member 1 ; genetics ; metabolism ; Antineoplastic Agents, Phytogenic ; administration & dosage ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Caspase 3 ; genetics ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Humans ; KB Cells ; Mouth Neoplasms ; metabolism ; pathology ; Podophyllotoxin ; administration & dosage ; analogs & derivatives ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Proto-Oncogene Proteins p21(ras) ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Tumor Suppressor Protein p53 ; genetics ; metabolism ; bcl-2-Associated X Protein ; genetics ; metabolism

ATP-Binding Cassette Sub-Family B Member 2 ; ATP-Binding Cassette Transporters ; metabolism ; ATP-Binding Cassette, Sub-Family B, Member 3 ; Calnexin ; metabolism ; Calreticulin ; metabolism ; Carcinoma, Squamous Cell ; metabolism ; pathology ; virology ; Cervical Intraepithelial Neoplasia ; metabolism ; pathology ; virology ; Cysteine Endopeptidases ; metabolism ; Female ; HLA-A Antigens ; metabolism ; Human papillomavirus 16 ; isolation & purification ; Humans ; Lymphatic Metastasis ; Papillomavirus Infections ; Proteasome Endopeptidase Complex ; metabolism ; Uterine Cervical Neoplasms ; metabolism ; pathology ; virology