Assessment of clinical outcomes in breast cancer patients treated with taxanes: multi-analytical approach

Polymorphisms in genes encoding CYPs (Phase I) and ABCB1 (Phase III) enzymes may attribute to variability of efficacy of taxanes. The present study aims to find the influence of CYP and ABCB1 gene polymorphisms on taxanes based clinical outcomes. 132 breast cancer patients treated with taxanes based chemotherapy were genotyped for CYP3A4*1B, CYP3A5*3, CYP1B1*3, CYP2C8*3, ABCB1 1236C>T, 2677G>T/A and 3435C>T polymorphisms using PCR-RFLP. Associations of genetic variants with clinical outcomes in terms of response in 58 patients receiving neo-adjuvant chemotherapy (NACT), and chemo-toxicity in 132 patients were studied. Multifactor dimensionality reduction (MDR) analysis was performed to evaluate higher order gene–gene interactions with clinical outcomes. Pathological response to taxane based NACT was associated with GA genotype as well as A allele of CYP3A5*3 polymorphism (P_corr = 0.0465, P_corr = 0.0465). Similarly, association was found in dominant model of CYP3A5*3 polymorphism with responders (P_corr = 0.0465). Haplotype analysis further revealed A_CYP3A4–A_CYP3A5 haplotype to be significantly associated with responders (P_corr = 0.048). In assessing toxicity, significant association of variant (TT) genotype and T allele of ABCB1 2677G>T/A polymorphism, was found with ‘grade 1 or no leucopenia’ (P_corr = 0.0465, P_corr = 0.048). On evaluating higher order gene–gene interaction models by MDR analysis, CYP3A5*3; ABCB11236C>T and ABCB1 2677G>T/A; ABCB1 3435C>T and CYP1B1*3 showed significant association with treatment response, grade 2–4 anemia and dose delay/reduction due to neutropenia (P = 0.024, P = 0.004, P = 0.026), respectively. Multi-analytical approaches may provide a better assessment of pharmacogenetic based treatment outcomes in breast cancer patients treated with taxanes.     

Further evidence for the contribution of the vascular endothelial growth factor gene in coronary artery disease susceptibility

Coronary artery disease (CAD) receives intensive attentions in the research of cardiovascular diseases, due to its high incidence and severe impact on the quality of life vascular endothelial growth factor (VEGF), a potent angiogenic and vascular permeability factor, has been strongly implicated in the pathogenesis of CAD. Genetic markers in different regions of the VEGF gene have a plausible role in modulating the risk of CAD. To identify the markers contributing to the genetic susceptibility to CAD, we examined the potential association between CAD and 10 single nucleotide polymorphisms (SNPs, rs699947, rs1570360, rs2010963, rs833068, rs3024997, rs3025000, rs3025010, rs3025020, rs3025030, rs3025039) of the VEGF gene using the MassARRAY system. Participants included 242 CAD patients and 253 healthy controls from a Chinese Han Population (He'nan Province, China). The allelic or genotypic frequencies of the rs699947 (5′ untranslated regions, 5′UTR) and rs2010963 (5′UTR) polymorphisms in the CAD patients were significantly different from those in the healthy controls. The CAD patients had significantly higher frequency of the rs699947 A allele (χ² = 11.141, P = 0.001, OR = 1.665, 95% CI = 1.232–2.250) and rs2010963 C allele (χ² = 13.593, P = 0.0002, OR = 1.611, 95% CI = 1.249–2.077). Strong linkage disequilibrium was observed in the rs699947–rs1570360–rs2010963 haplotype block (D’ > 0.9). Significantly more C–G–C haplotypes (P = 0.040) and significantly fewer C–G–G haplotypes (P = 0.0004) were found in the CAD patients. The possible association of rs699947 and rs2010963 with CAD risks warrant confirmation in independent case–control studies and may be informative for future investigations on the pathogenesis of CAD.     

Tumor necrosis factor alpha − 308G>A, − 863C>A, − 857C>T gene polymorphisms and tuberculosis susceptibility: A meta-analysis

Background/aims

A large number of studies have shown that polymorphisms in the tumor necrosis factor-α (TNF-α, TNFA) gene are implicated in susceptibility to tuberculosis (TB). However, the results are inconsistent. We performed this meta-analysis to estimate the association between polymorphisms in the TNFA gene and TB susceptibility.

Methods

Relevant studies published before March 2012 were identified by searching PubMed, ISI web of knowledge, EBSCO and CNKI. The strength of relationship between the TNFA gene and TB susceptibility was assessed using odds ratios (ORs).

Results

A total number of twenty-three case–control studies including 3630 cases and 4055 controls were identified referring to three previously chosen single-nucleotide polymorphisms (SNPs): − 308G>A, − 863C>A and − 857C>T. No association was found between − 308G>A, − 863C>A and TB susceptibility: − 308G>A (GG + GA vs. AA): OR 0.85, 95%CI: 0.55–1.30, P = 0.44; − 863C>A (CC + CA vs. AA): OR 0.93, 95%CI: 0.84–1.81, P = 0.83. Increased risk of TB was associated with − 857C>T in the dominant genetic model (CC + CT vs. TT: OR 2.13, 95%CI: 1.25–3.63, P = 0.01), the heterozygote comparison (CT vs. TT: OR 2.69, 95%CI: 1.44–5.02, P = 0.00) and the homozygote comparison (CC vs. TT: OR 2.08, 95%CI: 1.22–3.53, P = 0.01) in Asian subjects.

Conclusion

There is an increased association between TNFA − 857C>T polymorphism and TB risk among Asian subjects. No association was found between − 308G>A and − 863C>A with TB risk. Due to several limitations in the present study, well-designed epidemiological studies with large sample size among different ethnicities should be performed in the future.     

Combined analysis of polymorphism variants in hMTH1, hOGG1 and MUTYH genes on the risk of type 2 diabetes in the Chinese population

Reactive oxygen species are considered to play a role in the development of type 2 diabetes mellitus (T2DM) and its complications. 8-Oxoguanine, which is one of the major oxidation base lesions produced by reactive oxygen species, may cause G:C to T:A transversion mutations because it can mispair with adenine. hMTH1 (human mutT homolog 1), hOGG1 (human 8-oxoguanine glycosylase 1) and MUTYH (human mutY homolog) genes constitute the 8-oxoG repair pathway. In this study, we screened for the polymorphism variants Val83Met (c.247G>A, rs4866) in hMTH1; c.-53G>C (rs56387615), c.-23A>G (rs1801129) and c.-18G>T (rs1801126) in the 5′-UTR of hOGG1; and AluYb8 insertion in MUTYH (AluYb8MUTYH, rs10527342) and investigated their synergistic effect on the risk of T2DM in the Chinese population. The genotypes were determined by electrophoresis, a high-resolution melting technique and sequencing of PCR products. Our results showed that the c.247G>A variant in the hMTH1 gene increased the risk of T2DM in > 55 years of age groups (OR = 1.579; 95%CI: 1.029–2.421). The set of c.-53G>C, c.-23A>G and c.-18G>T variants detected in the 5′-UTR of the hOGG1 gene and the AluYb8 insertion in the MUTYH gene were each associated with an increased risk of T2DM (OR = 1.507, 95%CI: 1.122–2.024; OR = 1.229, 95%CI: 1.030–1.466, respectively). Combined analysis of the variations among the three genes suggested that the c.247G>A variant in hMTH1 combined with AluYb8MUTYH variant had a synergistic effect on increasing the risk of T2DM (OR = 1.635; 95%CI: 1.147–2.330). This synergy was also observed between the variants in the 5′-UTR of the hOGG1 and the AluYb8MUTYH variant (OR = 1.804; 95%CI: 1.254–2.595). Our results suggest, for the first time, the combined effects of AluYb8MUTYH with either hMTH1 c.247G>A or variants in the 5′-UTR of the hOGG1 on the risk of T2DM.     

The Sequence Dependence of Human Nucleotide Excision Repair Efficiencies of Benzo[a]pyrene-derived DNA Lesions: Insights into the Structural Factors that Favor Dual Incisions

Nucleotide excision repair (NER) is a vital cellular defense system against carcinogen-DNA adducts, which, if not repaired, can initiate cancer development. The structural features of bulky DNA lesions that account for differences in NER efficiencies in mammalian cells are not well understood. In vivo, the predominant DNA adduct derived from metabolically activated benzo[a]pyrene (BP), a prominent environmental carcinogen, is the 10S (+)-trans-anti-[BP]-N²-dG adduct (G*), which resides in the B-DNA minor groove 5′-oriented along the modified strand. We have compared the structural distortions in double-stranded DNA, imposed by this adduct, in the different sequence contexts 5′-…CGG*C…, 5′-…CG*GC…, 5′-…CIG*C… (I is 2′-deoxyinosine), and 5′-…CG*C…. On the basis of electrophoretic mobilities, all duplexes manifest moderate bends, except the 5′-…CGG*C…duplex, which exhibits an anomalous, slow mobility attributed to a pronounced flexible kink at the site of the lesion. This kink, resulting from steric hindrance between the 5′-flanking guanine amino group and the BP aromatic rings, both positioned in the minor groove, is abolished in the 5′-…CIG*C…duplex (the 2′-deoxyinosine group, I, lacks this amino group). In contrast, the sequence-isomeric 5′-…CG*GC…duplex exhibits only a moderate bend, but displays a remarkably increased opening rate at the 5′-flanking base pair of G*, indicating a significant destabilization of Watson-Crick hydrogen bonding. The NER dual incision product yields were compared for these different sequences embedded in otherwise identical 135-mer duplexes in cell-free human HeLa extracts. The yields of excision products varied by a factor of as much as ∼ 4 in the order 5′-...CG*GC…> 5′...CGG*C…≥ 5′...CIG*C…≥ 5′-…CG*C…. Overall, destabilized Watson-Crick hydrogen bonding, manifested in the 5′-...CG*GC...duplex, elicits the most significant NER response, while the flexible kink displayed in the sequence-isomeric 5′-...CGG*C...duplex represents a less significant signal in this series of substrates. These results demonstrate that the identical lesion can be repaired with markedly variable efficiency in different local sequence contexts that differentially alter the structural features of the DNA duplex around the lesion site.     

Interleukin (IL)-21 promoter polymorphism increases the risk of thyroid cancer in Chinese population

Polymorphisms in Interleukin (IL)-21 have been researched in several cancers, but the association between IL-21 polymorphisms and thyroid cancer remains unclarified. This case–control study explored the role of five tagSNPs (rs12508721C > T, rs907715G > A, rs13143866G > A, rs2221903A > G and rs4833837A > G) in IL-21 gene in thyroid cancer development. IL-21 genotypes were examined in 615 thyroid cancer patients and 600 controls in Chinese population, and the associations with the risk of thyroid cancer were estimated by logistic regression. Moreover, the potential role of rs12508721C > T in thyroid cancer was further explored by biochemical assays. Compared with the rs12508721CC genotype, CT genotype presented a significantly decreased risk of thyroid cancer (adjusted odds ratios [OR] = 0.72; 95%CI = 0.57–0.94), the TT carriers had a further decreased risk of thyroid cancer (OR = 0.56; 95%CI = 0.41–0.87). Furthermore, our quantitative real-time PCR and Enzyme-linked immunosorbent assay (ELISA) results demonstrated that the presence of rs12508721T allele led to more IL-21 expression. However, no significant difference was found in genotype frequencies for other four sites between cases and controls. These findings suggested that rs12508721 polymorphism in IL-21 might be a genetic modifier for the development of thyroid cancer.     

Cloning and expression analysis of novel Aux/IAA family genes in Gossypium hirsutum

The associations between polymorphisms of prostate stem cell antigen (PSCA-rs2294008C > T and -rs2976392G > A) and gastric cancer (GC) risk for Eastern Asians have been commonly studied, but the results were conflicting. The aim of the present study was to further assess the associations by the method of meta-analysis. The databases of Medline, Embase and CNKI (up to May 25th, 2011) were retrieved to identify eligible case-control studies. Odds ratio (OR) and 95% confidence interval (95%CI) were used to present the strength of the associations. In total, eight case-control studies in seven articles with 16792 individuals (9738 cases of GC and 7054 controls) were included in this meta-analysis. Through quantitative analyses, we found that T allele of rs2294008C > T and A allele of rs2976392G > A were significantly associated with increased GC risk [rs2294008C > T: OR (95%CI) = 1.31 (1.22-1.42), P_z-test < 0.001, P_{heterogeneity} = 0.166 for TT vs. C carriers; rs2976392G > A: OR (95%CI) = 1.36(1.24-1.50), P_z-test = 0.015, P_{heterogeneity} = 0.111 for AA vs. G carriers]. The results of subgroup analyses (according to histopathology, countries and sources of controls) indicated that T allele of rs2294008C > T and A allele rs2976392G > A were associated with increased risk of both intestinal- and diffuse-type GC, and associated with increased risk of GC for Chinese, Japanese, Koreans, PCC and HCC/PHCC. Furthermore, T allele of rs2294008C > T was also associated with increased risk of cardia and non-cardia GC, and associated with increased risk of GC for males and females. Besides those, this meta-analysis also indicated that the interactions between T allele of rs2294008C > T and A allele of rs2976392G > A was associated with increased risk of GC (A-T vs. G-T: OR = 1.16, 95%CI = 1.06-1.27, P_z-test = 0.001, P_{heterogeneity} = 0.835). Although modest limitations and potential bias cannot be eliminated, this meta-analysis suggests that PSCA -rs2294008C > T and -rs2976392G > A are potential factors of GC development for Eastern Asians, and future work may incorporate these findings and evaluate these variants as potential markers for screening and early diagnosis of GC.     

Synthesis and characterization of Os(II)(dpop′) (dpop′ = dipyrido(2,3-a;3′,2′-j)phenazine) complexes with 2,2′-bipyridine(bpy); 2,2′-bipyrimidine(bpm) and 2,3-bis(2-pyridyl)pyrazine(dpp)

New Os(II) complexes including [Os(dpop′)₂](PF₆)₂ (dpop′= dipyrido(2,3-a;3′,2′-j)phenazine) and a series of mixed ligand [Os(dpop′)(N-N)Cl]PF₆ (N-N = 2,2′-bipyridine(bpy); 2,2′-bipyrimidine(bpm) and 2,3-bis(2-pyridyl)pyrazine(dpp)) were synthesized. The Os dπ → dpop′ π^∗ MLCT transitions for [Os(dpop′)₂]²⁺ are observed at lower energy than for Os dπ → tpy π^∗ (tpy = 2,2′:6′,2″-terpyridine) and Os dπ → tppz π^∗ (tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine) (The ligand abbreviations tpd, tpp and tpypz have also appeared in the literature for 2,3,5,6- tetrakis(2-pyridyl)pyrazine in addition to tppz.) MLCT transitions in the comparative [Os(tpy)₂]²⁺ and [Os(tppz)₂]²⁺ complexes. The Os dπ → dpop′ π^∗ MLCT transitions are observed at lower energy in mixed bidentate ligand N-N systems compared with [Os(dpop′)₂]²⁺. Cyclic voltammetry shows more positive osmium oxidation, and less negative ligand reduction potentials for [Os(dpop′)₂]²⁺ as compared to [Os(tpy)₂]²⁺ and [Os(tppz)₂]²⁺ complexes. The osmium oxidation potentials in mixed ligand [Os(dpop′)(N-N)Cl]⁺ complexes are at less positive potential than for the [Os(dpop′)₂]²⁺ ion. NMR results show different chemical shifts for ring protons either trans or cis to dpop′ in mixed ligand systems, and also show two geometrical isomers for the [Os(dpop′)(dpp)Cl]⁺ complex. The [Os(dpop′)(dpp)Cl]⁺ geometric isomer with the pyrazine ring of dpp trans to dpop′ is found more predominate by 1.0/0.7 over the isomer with the pyrazine ring of dpp cis to dpop′ and that inter-conversion of geometric isomers does not occur in room temperature solution on the NMR timescale.     

Association between osteoporosis and polymorphisms of the bone Gla protein, estrogen receptor 1, collagen 1-A1 and calcitonin receptor genes in Turkish postmenopausal women

In this study, we have investigated the association between osteoporosis and osteocalcin (BGLAP) − 298 C>T, estrogen receptor 1 (ER1) 397 T>C, collagen type1 alpha 1 (Col1A1) 2046 G>T and calcitonin receptor (CALCR) 1340 T>C polymorphisms. Genomic DNA was obtained from 266 persons (158 osteoporotic and 108 healthy controls). Genomic DNA was extracted from EDTA-preserved peripheral venous blood of patients and controls by a salting-out method and analyzed by PCR-RFLP. As a result, there was no statistically significant difference in the genotype and allele frequencies of patients and controls for BGLAP − 298 C>T, Col1A1 2046 G>T, ER1 397 T>C and CALCR 1340 T>C polymorphisms. However, ER1 CC genotype compared with TT + TC genotypes was found to increase the two fold the risk of osteoporosis [p = 0.039, OR = 2.156, 95% CI (1.083–4.293)] and CALCR CC genotype compared with TT + TC genotypes was found to have protective effect against osteoporosis [p = 0.045, OR = 0.471, 95% CI (0.237–0.9372)]. In the combined genotype analysis, ER1/CALCR TCCC combined genotype was estimated to have protective effect against osteoporosis [p = 0.0125, OR = 0.323, 95% CI (0.1383–0.755)] whereas BGLAP/Col1A1 CCTT and ER1/CALCR CCTT combined genotypes were estimated as risk factors for osteoporosis in Turkish population (p = 0.027, p = 0.009 respectively).     

Cox-2 gene variants in migraine

Purpose

Migraine is a multifactorial and complex disorder, and any clear diagnostic marker to assess the status of the migraineurs has not been established, yet. Nonsteroidal anti-inflammatory drugs reduce production of prostanoids including PGE2 by inhibiting COX-1 and/or COX-2, and thereby suppress inflammatory pain in patients suffering from rheumatoid arthritis, osteoarthritis, and migraine. Thus, COX-2 regulation is important in the pathogenesis and treatment of migraine. We prospectively investigated COX-2-765G → C and COX-2-1195A → G gene polymorphisms which may account for an increased risk of migraine.

Methods

The present analyses are based on 144 case subjects with migraine disease and 123 non-case subjects. Genotyping of COX-2 gene polymorphisms (COX-2-765G → C, COX-2-1195A → G) was detected by PCR-RFLP.

Results

We, for the first time, demonstrated positive association of COX-2 gene variants with an increased risk for development of migraine. Carriers of COX-2-765 C + genotype in controls were higher than in the patients (57.7% and 36.1% respectively; P < 0.0001) and the frequencies of G + genotype in patients were higher than in the controls (97.9% and 88.6% respectively; P: 0.002). In addition, frequencies of COX-2-765 GG and GC genotypes in patients were higher than in the controls (P < 0.0001, P < 0.0001 respectively). It seems that COX-2-765 G + genotype had increased and COX-2-765 C + genotype had decreased risk for migraine. In COX-2-1195 polymorphism only AG genotype was statistically significantly different in patients than in the controls (P < 0.05).

Conclusions

Our findings have suggested that COX-2-765 G + genotype could facilitate the development of migraine disease.     

Flavonoid glycosides of the black locust tree, Robinia pseudoacacia (Leguminosae)

Four flavone glycosides isolated from extracts of the leaves of Robinia pseudoacacia (Leguminosae) were characterised by spectroscopic and chemical methods as the 7-O-β-d-glucuronopyranosyl-(1 → 2)[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranosides of acacetin (5,7-dihydroxy-4′-methoxyflavone), apigenin (5,7,4′-trihydroxyflavone), diosmetin (5,7,3′-trihydroxy-4′-methoxyflavone) and luteolin (5,7,3′,4′-tetrahydroxyflavone). Assignment of glycosidic ¹H and ¹³C resonances in their NMR spectra was facilitated by ²J_HC correlations detected using the H2BC (heteronuclear two-bond correlation) pulse sequence. Spectroscopic analysis of two known triglycosides, acacetin 7-O-β-d-glucopyranosyl-(1 → 2)[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (previously unrecorded from this species) and acacetin 7-O-β-d-xylopyranosyl-(1 → 2)[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (‘acacetin trioside’), enabled inconsistencies in the literature relating to these structures to be resolved. Comparison of the flavonoid chemistry of leaves and flowers of R. pseudoacacia using LC-UV and LC-MS showed that flavone 7-O-glycosides, particularly of acacetin, predominated in the former, whereas the latter comprised mainly flavonol 3,7-di-O-glycosides, including several examples new to this species. Tissue dependent differences in flavonoid chemistry were also evident from the glycosylation patterns of the compounds.     

The synthesis and characterization of mixed ligand Ru(II) complexes with dipyrido(2,3-a:3′,2′-j)phenazine (dpop′) and 2,3,5,6-tetra(2-pyridyl)-pyrazine (tppz)

The synthesis of the mixed ligand mono metallic [Ru(dpop′)(tppz)]²⁺ and bimetallic [(dpop′)Ru(tppz)Ru(dpop′)]⁴⁺ (dpop′ = dipyrido(2,3-a:3′,2′-j)phenazine; tppz = 2,3,5,6 tetra-(2-pyridyl)pyrazine) complexes is described. The [Ru(dpop′)(tppz)]²⁺ complex display an intense absorption at 518 nm which is assigned to a Ru(dπ) → dpop′ (π∗) MLCT transition, and at 447 nm which is assigned to a Ru(dπ) → tppz(π∗) MLCT transition. It undergoes emission at RT in CH₃CN with λ_em = 722 nm. The bimetallic [(dpop′)Ru(tppz)Ru(dpop′)]⁴⁺ complex shows a low energy absorption shoulder near 635 nm assigned to a Ru(dπ) → tppz(π∗) MLCT transition and an intense peak at 542 nm due to Ru(dπ) → dpop′ (π∗) MLCT transition. The bimetallic complex also emits at RT in CH₃CN with λ_em = 785 nm. Cyclic voltammetry shows reversible Ru^+2/+3 oxidations at 1.68 V for the monometallic complex and Ru^+2/+3 oxidation couples at +1.94 and +1.70 V for the bimetallic complex.     

Mechanism divergence in microbial rhodopsins

A fundamental design principle of microbial rhodopsins is that they share the same basic light-induced conversion between two conformers. Alternate access of the Schiff base to the outside and to the cytoplasm in the outwardly open “E” conformer and cytoplasmically open “C” conformer, respectively, combined with appropriate timing of pKa changes controlling Schiff base proton release and uptake make the proton path through the pumps vectorial. Phototaxis receptors in prokaryotes, sensory rhodopsins I and II, have evolved new chemical processes not found in their proton pump ancestors, to alter the consequences of the conformational change or modify the change itself. Like proton pumps, sensory rhodopsin II undergoes a photoinduced E → C transition, with the C conformer a transient intermediate in the photocycle. In contrast, one light-sensor (sensory rhodopsin I bound to its transducer HtrI) exists in the dark as the C conformer and undergoes a light-induced C → E transition, with the E conformer a transient photocycle intermediate. Current results indicate that algal phototaxis receptors channelrhodopsins undergo redirected Schiff base proton transfers and a modified E → C transition which, contrary to the proton pumps and other sensory rhodopsins, is not accompanied by the closure of the external half-channel. The article will review our current understanding of how the shared basic structure and chemistry of microbial rhodopsins have been modified during evolution to create diverse molecular functions: light-driven ion transport and photosensory signaling by protein–protein interaction and light-gated ion channel activity.     

Association of functional FEN1 genetic variants and haplotypes and breast cancer risk

Aim

As a tumor suppressor, FEN1 plays an essential role in preventing tumorigenesis. Two functional germline variants (-69G > A and 4150G > T) in the FEN1 gene have been associated with DNA damage levels in coke-oven workers and multiple cancer risk in general populations. However, it is still unknown how these genetic variants are involved in breast cancer susceptibility.

Methods

We investigated the association between these polymorphisms and breast cancer risk in two independent case–control sets consisted of a total of 1100 breast cancer cases and 1400 controls. The influence of these variations on FEN1 expression was also examined using breast normal tissues.

Results

It was found that the FEN1-69GG genotypes were significantly correlated to increased risk for developing breast cancer compared with the -69AA genotype in both sets [Jinan set: odds ratios (OR) = 1.41, 95% confidence interval (CI) = 1.20–1.65, P = 1.9×10^− 5; Huaian set: OR = 1.51, 95% CI = 1.22–1.86, P = 1.7×10^− 4]. Similar results were observed for 4150G > T polymorphism. The genotype–phenotype correlation analyses demonstrated that the -69G or 4150G allele carriers had more than 2-fold decreased FEN1 expression in breast tissues compared with -69A or 4150T carriers, suggesting that lower FEN1 expression may lead to higher risk for malignant transformation of breast cells.

Conclusion

Our findings highlight FEN1 as an important gene in human breast carcinogenesis and genetic variants in FEN1 confer susceptibility to breast cancer.     

Clinical and molecular genetic study of infantile-onset Pompe disease in Chinese patients: Identification of 6 novel mutations

Pompe disease is an autosomal recessive disorder and is caused by a deficiency in acid alpha-glucosidase (GAA). A broad range of studies have been performed on Pompe patients from different countries. However, the clinical course and molecular basis of the disease in Mainland China have not been well defined. In the present study, we examined a total of 18 Chinese children with infantile-onset Pompe disease to better understand the clinical and genetic features in this population. The median age at symptom onset was 3.6 months (range: 1.7–6.8 months) and 6.3 months at diagnosis (range: 2.5–9.3 months). All but 1 patient died at a median age of 8.2 months (range: 4.7–18.7 months). Molecular analysis revealed 20 different mutations, 6 of which are novel (c.1356delC, c.378G > A, c.1827C > G, c.859-2 A > T, c.1551 + 2T > G, and c.1465G > T). The most common mutation in the study was c.1935C > A, accounting for 25% (9/36 alleles) of the mutations. Our study provides the first comprehensive examination of the clinical course of infantile-onset Pompe disease and mutations of the GAA gene for patients in Mainland China. Our results confirm the high prevalence of the c.1935C > A mutation, previously reported for other populations, in Mainland Chinese patients with infantile-onset Pompe disease. Furthermore, six novel mutations in the GAA gene are reported for the first time.     

Role of CYP1A2*1F polymorphism in cancer risk: Evidence from a meta-analysis of 46 case–control studies

Background

Emerging evidence showed that the common polymorphism (CYP1A2*1F, rs762551 C → A) in the promoter region of the CYP1A2 gene might be associated with susceptibility to cancer in humans. But individually published results were inconclusive. The aim of this meta-analysis is to investigate the association between CYP1A2*1F polymorphism and cancer risk.

Methods

The Pubmed, Embase, Web of Science and Chinese BioMedical databases were searched for all articles published up to September 1st, 2012. Statistical analyses were performed using the STATA 12.0 software.

Results

Forty-six case–control studies were included with a total of 22,993 cancer cases and 28,420 healthy controls. Meta-analysis results showed that the A allele of CYP1A2*1F polymorphism was associated with a decreased cancer risk (odds ratio [OR] = 0.92, 95% confidence interval [CI]: 0.87–0.98, P = 0.013). In the subgroup analysis by cancer types, the A allele of CYP1A2*1F polymorphism may increase the risk of breast cancer (OR = 1.05, 95% CI: 1.01–1.10, P = 0.024), and is also associated with a decreased risk of ovarian cancer (OR = 0.70, 95% CI: 0.54–0.89, P = 0.004). However, similar results were not found in lung, colorectal, bladder, endometrial, pancreatic and gastric cancers. Further subgroup analysis by ethnicity also showed a significant association between the A allele of CYP1A2*1F polymorphism and a decreased cancer risk among Caucasian populations (OR = 0.91, 95% CI: 0.84–0.98, P = 0.014); but no significant associations were observed among Asian populations.

Conclusions

Results from the current meta-analysis indicate that the A allele of CYP1A2*1F polymorphism may be associated with breast and ovarian cancer risk, especially among Caucasian populations.     

Mercaptoethanesulfonic acid (CoM imitator) interaction studies with nickel(II) complexes of pyridyl groups containing tetradentate ligands: Synthesis, structure, spectra and redox properties

Nickel(II) complexes of N,N′-dimethyl-N,N′-bis(pyridyl-2yl-methyl)ethylene-diamine (L¹), N,N′-dimethyl-N,N′-bis(pyridyl-2-ylmethyl)-1,2-diaminopropane (L²) and N,N′-dimethyl-N,N′-bis(pyridyl-2-ylmethyl)-1,3-diaminopropane (L³) were prepared and their spectroscopic and redox properties studied. The distorted octahedral structure was determined for [NiL³ClCH₃OH](ClO₄) by using X-ray crystallography. The electronic spectral behavior of the complexes at different pHs was analyzed; it is shown that a new band grew at the expense of the other band intensity in acid media. The redox properties of ligands and their complexes show the peaks of Ni(II) → Ni(III) and Ni(II) → Ni(0) as these were detected at low concentration while Ni(II) → Ni(I) process was detectable clearly at high concentration. Furthermore, the interaction studies of 2-mercaptoethanesulfonic acid as a simulator of coenzyme M reductase (CoM) with NiN₄ chromophores are discussed.     

Interleukin-1α − 899 (+ 4845) C→T polymorphism increases the risk of chronic periodontitis: Evidence from a meta-analysis of 23 case–control studies

Many epidemiological studies have indicated that interleukin-1α (IL-1α) − 899 (+ 4845) C→T polymorphism increases the risk of chronic periodontitis (CP), whereas some studies have reported opposite results. Accordingly, the aim of this meta-analysis is to investigate the association of the IL-1α − 899 (+ 4845) C→T polymorphism with CP. We searched the PubMed database up to May 1, 2013 and finally obtained 23 case–control studies. After data extraction, we performed meta-analysis using Comprehensive Meta-Analysis v2.2 software. The overall result based on the fixed-effect model showed that IL-1α − 899 (+ 4845) C→T polymorphism was significantly associated with increased risk of CP: [odds ratio (OR) = 1.29, 95% confidence interval (CI) = 1.15–1.44, p < 0.001] for T vs. C; (OR = 1.59, 95%CI = 1.22–2.07, p = 0.0005) for TT vs. CC; (OR = 1.30, 95% CI = 1.12–1.51, p = 0.0004) for CT vs. CC; and (OR = 1.40, 95% CI = 1.21–1.61, p < 0.001) for (CT+TT) vs. CC; (OR = 1.47, 95% CI = 1.16–1.87, p = 0.002) for TT vs. (CT+CC). Stratified analyses revealed that there was a significantly increased risk for Caucasians and Asians. In conclusion, current evidence showed that IL-1α − 899 (+ 4845) C→T polymorphism probably increased the risk of CP.     

Coordinate regulation of bovine prion protein gene promoter activity by two Sp1 binding site polymorphisms

Relationships between insertion/deletion (Ins/Del) polymorphisms of the bovine prion protein gene (PRNP) promoter and bovine spongiform encephalopathy (BSE) susceptibility have been reported. Our previous study has shown that polymorphisms of −6C → T included in the specific protein 1 (Sp1) site in the 5′-flanking region of bovine PRNP influence the promoter activity of bovine PRNP. The present study shows that 12 and 23 bp Ins/Del polymorphisms in the upstream region and an additional polymorphism (−47C → A) in the Sp1 binding site coordinately affect the promoter activity. Reporter gene assays demonstrated that the bovine PRNP promoter containing −47A and 23 bp Del/12 bp Ins or 23 bp Ins/12 bp Ins showed lower promoter activity compared with other haplotypes (23 bp Del/12 bp Ins or 23 bp Ins/12 bp Del with −47C) or the wild-type haplotype (23 bp Del/12 bp Del with −47C). Furthermore, gel shift assays showed that the binding activity of Sp1 to the PRNP promoter was influenced by both polymorphisms with corresponding effects on the promoter activity. The coordinate regulation of the bovine PRNP promoter suggests the two Sp1 binding site polymorphisms control Sp1 binding to the PRNP promoter and its activity.