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1.  Systematic Functional Characterization of Cytochrome P450 2E1 Promoter Variants in the Chinese Han Population 
PLoS ONE  2012;7(7):e40883.
CYP2E1 promoter polymorphisms can lead to significant interindividual differences in expression of CYP2E1. Using a database of CYP2E1 gene polymorphisms established in 2010, our study aimed to functionally characterize the single nucleotide polymorphisms (SNPs) of the promoter region and corresponding haplotypes in the Chinese Han population. Six novel SNPs and seven haplotypes with a frequency equal to or greater than 0.01 were constructed on a luciferase reporter system on the basis of site-directed mutagenesis. Dual luciferase reporter systems were used to analyze regulatory activity. The constructs including single novel SNP mutations exhibited insignificant change in luciferase activity, whereas, the activity produced by Haplo1(GTTGCTATAT), Haplo2 (CTTGCTATAT) and Haplo7 (GAGCTCACAT), containing a −333T>A polymorphism was significantly greater than for the wild type in Hep G2 cells (p<0.05), being 1.5−, 2.0− and 1.4− times greater respectively. These findings suggest the possibility of significant clinical prediction of adverse drug reaction and the facilitation of personalized medicine.
doi:10.1371/journal.pone.0040883
PMCID: PMC3398937  PMID: 22815852
2.  Genetic Polymorphisms in CYP2E1: Association with Schizophrenia Susceptibility and Risperidone Response in the Chinese Han Population 
PLoS ONE  2012;7(5):e34809.
Background
CYP2E1 is a member of the cytochrome P450 superfamily, which is involved in the metabolism and activation of both endobiotics and xenobiotics. The genetic polymorphisms of CYP2E1 gene (Chromosome 10q26.3, Accession Number NC_000010.10) are reported to be related to the development of several mental diseases and to be involved in the clinical efficacy of some psychiatric medications. We investigated the possible association of CYP2E1 polymorphisms with susceptibility to schizophrenia in the Chinese Han Population as well as the relationship with response to risperidone in schizophrenia patients.
Methods
In a case-control study, we identified 11 polymorphisms in the 5' flanking region of CYP2E1 in 228 schizophrenia patients and 384 healthy controls of Chinese Han origin. From among the cases, we chose 130 patients who had undergone 8 weeks of risperidone monotherapy to examine the relationship between their response to risperidone and CYP2E1 polymorphisms. Clinical efficacy was assessed using the Brief Psychiatric Rating Scale (BPRS).
Results
Statistically significant differences in allele or genotype frequencies were found between cases and controls at rs8192766 (genotype p = 0.0048, permutation p = 0.0483) and rs2070673 (allele: p = 0.0018, permutation p = 0.0199, OR = 1.4528 95%CI = 1.1487–1.8374; genotype: p = 0.0020, permutation p = 0.0225). In addition, a GTCAC haplotype containing 5 SNPs (rs3813867, rs2031920, rs2031921, rs3813870 and rs2031922) was observed to be significantly associated with schizophrenia (p = 7.47E-12, permutation p<0.0001). However, no association was found between CYP2E1 polymorphisms/haplotypes and risperidone response.
Conclusions
Our results suggest that CYP2E1 may be a potential risk gene for schizophrenia in the Chinese Han population. However, polymorphisms of the CYP2E1 gene may not contribute significantly to individual differences in the therapeutic efficacy of risperidone. Further studies in larger groups are warranted to confirm our results.
doi:10.1371/journal.pone.0034809
PMCID: PMC3350493  PMID: 22606226
3.  Damaged DNA-binding Protein 1 (DDB1) Interacts with Cdh1 and Modulates the Function of APC/CCdh1* 
The Journal of Biological Chemistry  2010;285(24):18234-18240.
APC/CCdh1 plays a key role in mitotic exit and has essential targets in the G1 phase; however, these mechanisms are poorly understood. In this report, we provide evidence that damaged DNA-binding protein 1 (DDB1) is capable of binding the WD40 domains of Cdh1, but not of Cdc20, through its BPA and BPC domains. Moreover, cells lacking DDB1 exhibit markedly elevated levels of the protein substrates of APC/CCdh1. Depletion of DDB1 in mitotic cells significantly delays mitotic exit, which demonstrates that the interaction between DDB1 and Cdh1 plays a critical role in regulating APC/CCdh1 activity. However, cells depleted of Cdh1 demonstrated no change in the UV-induced degradation of Cdt1, the main function of DDB1 as an E3 ligase. Strikingly, the APC/CCdh1 substrate levels are normal in cell knockdowns of Cul4A and Cul4B, which, along with DDB1, form an E3 ligase complex. This finding indicates that DDB1 modulates the function of APC/CCdh1 in a manner independent on the Cul4-DDB1 complex. Our results suggest that DDB1 may functionally regulate mitotic exit by modulating APC/CCdh1 activity. This study reveals that there may be cross-talk among DDB1, Cdh1, and Skp2 in the control of cell cycle division.
doi:10.1074/jbc.M109.094144
PMCID: PMC2881748  PMID: 20395298
Cell Cycle; Checkpoint Control; DNA Damage; E3 Ubiquitin Ligase; Protein-Protein Interactions; APC; Cdh1; DDB1; Mitotic Exit
4.  Binding of spermine and ifenprodil to a purified, soluble regulatory domain of the N-methyl-d-aspartate receptor 
Journal of neurochemistry  2008;107(6):1566-1577.
The binding of spermine and ifenprodil to the amino terminal regulatory (R) domain of the N-methyl-d-aspartate receptor was studied using purified regulatory domains of the NR1, NR2A and NR2B subunits, termed NR1-R, NR2A-R and NR2B-R. The R domains were overexpressed in Escherichia coli and purified to near homogeneity. The Kd values for binding of [14C]spermine to NR1-R, NR2A-R and NR2B-R were 19, 140 and 33 µM, respectively. [3H]Ifenprodil bound to NR1-R (Kd, 0.18 µM) and NR2B-R (Kd, 0.21 µM), but not to NR2A-R at the concentrations tested (0.1 to 0.8 µM). These Kd values were confirmed by circular dichroism measurements. The Kd values reflected their effective concentrations at intact NR1/NR2A and NR1/NR2B receptors. The results suggest that effects of spermine and ifenprodil on NMDA receptors occur through binding to the regulatory domains of the NR1, NR2A and NR2B subunits. The binding capacity of spermine or ifenprodil to a mixture of NR1-R and NR2A-R or NR1-R and NR2B-R was additive with that of each individual R domain. Binding of spermine to NR1-R and NR2B-R was not inhibited by ifenprodil and vice versa, indicating that the binding sites for spermine and ifenprodil on NR1-R and NR2B-R are distinct.
doi:10.1111/j.1471-4159.2008.05729.x
PMCID: PMC2690642  PMID: 19014388
spermine; ifenprodil; aminoglycoside antibiotics; regulatory domain of N-methyl-d-aspartate receptor
5.  Gene expression profiling spares early breast cancer patients from adjuvant therapy: derived and validated in two population-based cohorts 
Breast Cancer Research  2005;7(6):R953-R964.
Introduction
Adjuvant breast cancer therapy significantly improves survival, but overtreatment and undertreatment are major problems. Breast cancer expression profiling has so far mainly been used to identify women with a poor prognosis as candidates for adjuvant therapy but without demonstrated value for therapy prediction.
Methods
We obtained the gene expression profiles of 159 population-derived breast cancer patients, and used hierarchical clustering to identify the signature associated with prognosis and impact of adjuvant therapies, defined as distant metastasis or death within 5 years. Independent datasets of 76 treated population-derived Swedish patients, 135 untreated population-derived Swedish patients and 78 Dutch patients were used for validation. The inclusion and exclusion criteria for the studies of population-derived Swedish patients were defined.
Results
Among the 159 patients, a subset of 64 genes was found to give an optimal separation of patients with good and poor outcomes. Hierarchical clustering revealed three subgroups: patients who did well with therapy, patients who did well without therapy, and patients that failed to benefit from given therapy. The expression profile gave significantly better prognostication (odds ratio, 4.19; P = 0.007) (breast cancer end-points odds ratio, 10.64) compared with the Elston–Ellis histological grading (odds ratio of grade 2 vs 1 and grade 3 vs 1, 2.81 and 3.32 respectively; P = 0.24 and 0.16), tumor stage (odds ratio of stage 2 vs 1 and stage 3 vs 1, 1.11 and 1.28; P = 0.83 and 0.68) and age (odds ratio, 0.11; P = 0.55). The risk groups were consistent and validated in the independent Swedish and Dutch data sets used with 211 and 78 patients, respectively.
Conclusion
We have identified discriminatory gene expression signatures working both on untreated and systematically treated primary breast cancer patients with the potential to spare them from adjuvant therapy.
doi:10.1186/bcr1325
PMCID: PMC1410752  PMID: 16280042
6.  Colorectal cancers with microsatellite instability display mRNA expression signatures characteristic of increased immunogenicity 
Molecular Cancer  2004;3:21.
Background
Colorectal cancers displaying high-degree microsatellite instability (MSI-H) have an improved prognosis compared to microsatellite stable (MSS) cancers. The observation of pronounced lymphocytic infiltrates suggests that MSI-H cancers are inherently more immunogenic. We aimed to compare the gene expression profiles of MSI-H and MSS cancers to provide evidence for an activated immune response in the former.
Results
We analysed tissue from 133 colorectal cancer patients with full consent and Local Ethics Committee approval. Genomic DNA was analysed for microsatellite instability in BAT-26. High-quality RNA was used for microarray analysis on the Affymetrix® HG-U133A chip. Data was analysed on GeneSpring software version 6.0. Confirmatory real-time RT-PCR was performed on 28 MSI-H and 26 MSS cancers. A comparison of 29 MSI-H and 104 MSS cancers identified 2070 genes that were differentially expressed between the two groups [P < 0.005]. Significantly, many key immunomodulatory genes were up-regulated in MSI-H cancers. These included antigen chaperone molecules (HSP-70, HSP-110, Calreticulin, gp96), pro-inflammatory cytokines (Interleukin (IL)-18, IL-15, IL-8, IL-24, IL-7) and cytotoxic mediators (Granulysin, Granzyme A). Quantitative RT-PCR confirmed up-regulation of HSP-70 [P = 0.016], HSP-110 [P = 0.002], IL-18 [P = 0.004], IL-8 [0.002] and Granulysin [P < 0.0001].
Conclusions
The upregulation of a large number of genes implicated in immune response supports the theory that MSI-H cancers are immunogenic. The novel observation of Heat Shock Protein up-regulation in MSI-H cancer is highly significant in light of the recognised roles of these proteins in innate and antigen-specific immunogenicity. Increased mRNA levels of pro-inflammatory cytokines and cytotoxic mediators also indicate an activated anti-tumour immune response.
doi:10.1186/1476-4598-3-21
PMCID: PMC514528  PMID: 15298707

Results 1-6 (6)