Large-scale prospective genome-wide association study of oxaliplatin in stage II/III colon cancer and neuropathy.

BACKGROUND: The severity of oxaliplatin (L-OHP)-induced peripheral sensory neuropathy (PSN) exhibits substantial interpatient variability, and some patients suffer from long-term, persisting PSN. To identify single-nucleotide polymorphisms (SNPs) predicting L-OHP-induced PSN using a genome-wide association study (GWAS) approach. PATIENTS AND METHODS: A large prospective GWAS including 1379 patients with stage II/III colon cancer who received L-OHP-based adjuvant chemotherapy (mFOLFOX6/CAPOX) under the phase II (JOIN/JFMC41) or the phase III (ACHIVE/JFMC47) trial. Firstly, GWAS comparison of worst grade PSN (grade 0/1 versus 2/3) was carried out. Next, to minimize the impact of ambiguity in PSN grading, extreme PSN phenotypes were selected and analyzed by GWAS. SNPs that could predict time to recovery from PSN were also evaluated. In addition, SNPs associated with L-OHP-induced allergic reactions (AR) and time to disease recurrence were explored. RESULTS: No SNPs exceeded the genome-wide significance (P < 5.0 × 10-8) in either GWAS comparison of worst grade PSN, extreme PSN phenotypes, or time to recovery from PSN. An association study focusing on AR or time to disease recurrence also failed to reveal any significant SNPs. CONCLUSION: Our results highlight the challenges of utilizing SNPs for predicting susceptibility to L-OHP-induced PSN in daily clinical practice.

Large-scale prospective pharmacogenomics study of oxaliplatin-induced neuropathy in colon cancer patients enrolled in the JFMC41-1001-C2 (JOIN Trial).

BACKGROUND: Peripheral sensory neuropathy (PSN) is a dose-limiting toxicity of oxaliplatin-based chemotherapy. Several genetic markers have been shown to predict oxaliplatin-induced PSN; however, results remain to be validated in a large-scale and prospective pharmacogenomics study. PATIENTS AND METHODS: Among 882 patients enrolled in the JFMC41-1001-C2 (JOIN trial), which was designed to investigate the tolerability of adjuvant-modified FOLFOX6 (mFOLFOX6) in Japanese Patients with stage II or III colon cancers undergoing curative resection, 465 patients were eligible for this pharmacogenomics analysis. Twelve single-nucleotide polymorphisms (SNPs) were selected based on published data. The effect of each genotype on time to PSN onset was evaluated in all patients (n = 465) using the Cox proportional hazard model. For the association analysis between severity of PSN and 12 SNP markers, 84 patients who failed to complete 12 cycles of mFOLFOX6 from grade 0/1 PSN group were excluded because the termination of the protocol treatment had been caused by reasons other than PSN. RESULTS: Comparison of grade 0/1 PSN with grade 2/3 PSN or grade 3 PSN showed no significant associations with any of the 12 SNP markers after adjustment for total dose of oxaliplatin. Time-to-onset analysis also failed to reveal any significant differences. CONCLUSIONS: Our large-scale and prospective pharmacogenomics study of Japanese patients receiving protocol treatment of adjuvant mFOLFOX6 could not verify a role for any of the 12 SNP markers reported as being significantly associated with PSN. Considering the OR observed in this study (range: 0.76-1.89), further evaluation of these 12 SNP markers in the context of L-OHP-induced PSN is unlikely to be clinically informative.

Tooth loss and atherosclerosis: the Nagahama Study.

Several epidemiologic studies have suggested that oral disease is a risk factor for cardiovascular disease (CVD). However, whether a clinically significant association exists between the 2 disorders remains controversial. Here, we investigated the association between tooth loss, as an indicator of oral disease, and arterial stiffness, as a marker of atherosclerosis, in Japanese adults. Cross-sectional data were collected for 8,124 persons aged 30 to 75 y with no history of tooth loss for noninflammatory reasons, such as orthodontic treatment, malposition, and trauma. Participants received a comprehensive dental examination and extensive in-person measurements of CVD risk factors, and arterial stiffness was evaluated using the cardio-ankle vascular index (CAVI). We examined the association between CAVI and tooth loss using general linear models with adjustment for age, sex, body mass index, smoking status, hemoglobin A1c, and a history of insulin or hypoglycemic medication depending on the model. In addition, we performed an analysis that included interaction terms of the centered variables tooth loss, sex, and age. The results of the multiple regression analysis that included the interaction terms detected that the relationship between CAVI and tooth loss was dependent on sex, with only men showing a positive correlation (ß for interaction = 0.04; 95% confidence interval, 0.02-0.06). The findings from this study suggest that a linear relationship exists between tooth loss and degree of arterial stiffness and that the association differed depending on sex.

Roles of major oligosaccharides on Cry j 1 in human immunoglobulin E and T cell responses.

BACKGROUND: We have demonstrated that carbohydrates in Cry j 1, the major allergen of Cryptomeria japonica pollen, play a major role in promoting Cry j 1-specific Th2 response. However, little is known as to whether the carbohydrates directly participate in allergic responses. OBJECTIVE: We sought to determine whether Cry j 1-related oligosaccharides function as IgE and/or T cell epitopes. In addition, the regulatory effect of Cry j 1-related oligosaccharide on Cry j 1-specific T cell responses was investigated. METHODS: Two monovalent oligosaccharides largely found on Cry j 1, Manalpha1-6(Manalpha1-3)(Xylbeta1-2)Manbeta1-4GlcNAcbeta1-4(Fucalpha1-3)GlcNAc (M3FX), and GlcNAcbeta1-2Manalpha1-6(GlcNAcbeta1-2Manalpha1-3)(Xylbeta1-2)Manbeta1-4GlcNAcbeta1-4(Fucalpha1-3)GlcNAc (GN2M3FX) were prepared. Manalpha1-2Manalpha1-6(Manalpha1-2Manalpha1-3)Manalpha1-6(Manalpha1-2Manalpha1-2Manalpha1-3)Manbeta1-4GlcNAcbeta1-4GlcNAc (M9A) was used as control. Competitive inhibition ELISA for Cry j 1-specific IgE was performed using these oligosaccharides as inhibitors. In addition, T cell lines specific for Cry j 1 or purified protein derivative of Mycobacterium tubecurosis (PPD) were established, and cellular responses against these oligosaccharides were investigated in the presence or absence of the respective antigens. RESULTS: Overall, neither M3FX nor GN2M3FX displayed inhibitory effect on the binding between IgE and Cry j 1. In addition, M3FX did not by itself stimulate Cry j 1 or PPD-specific T cells. However, M3FX significantly inhibited Cry j 1-induced proliferation and IL-4 production in Cry j 1-specific T cells. Such an inhibitory effect was not seen in PPD-specific T cell responses. CONCLUSION: These results suggest that Cry j 1-related oligosaccharides are not major epitopes for IgE or T cells. However, these oligosaccharides have a novel potential to inhibit Cry j 1-specific T cell responses selectively.

Involvement of reactive oxygen species in the induction of (S)-N-p-coumaroyloctopamine accumulation by beta-1,3-glucooligosaccharide elicitors in potato tuber tissues.

Treatment of potato tuber tissues with beta-1,3-glucooligosaccharide induces accumulation of (S)-N-p-coumaroyloctopamine (p-CO). We examined the role of reactive oxygen species (ROS) and nitric oxide (NO) in the signal transduction leading to p-CO accumulation. Induction was suppressed by an NADPH-oxidase inhibitor, diphenyleneiodonium chloride, and oxygen radical scavengers. H2O2 was generated in the tuber tissue within a few minutes of treatment with beta-1,3-glucooligosaccharide. On the other hand, treatment with NO specific scavenger, nitric oxide synthase inhibitor, and serine protease inhibitor did not inhibit p-CO induction. Our findings suggest that ROS generated by the action of NADPH-oxidase play an important role in this system, while NO and serine protease are unlikely to be involved in this process.

Beta-1,3-glucooligosaccharide induced activation of four enzymes responsible for N-p-coumaroyloctopamine biosynthesis in potato (Solanum tuberosum cv.) tuber tissue.

Potato tuber disks, when treated with laminarin, a beta-1,3-glucooligosaccharide from Laminaria digitata, accumulate a hydroxycinnamoyl amide compound, N-p-coumaroyloctopamine (p-CO). The biosynthesis of p-CO was investigated by feeding experiments, in order to show that the precursors of N-p-coumaroyl and octopamine moieties of p-CO are L-phenylalanine and L-tyrosine, respectively. The treatment of potato tuber tissue with laminarin resulted in elevated activities of four enzymes which are putatively involved in p-CO biosynthesis: phenylalanine ammonia lyase (PAL; EC 4.3.1.5), 4-hydroxycinnamic acid:CoA ligase (4CL; EC 6.2.1.12), hydroxycinnamoyl-CoA:tyramine N-(hydroxycinnamoyl)transferase (THT; EC 2.3.1.110) and tyrosine decarboxylase (TyrDC; EC 4.1.1.25). Among these, the response of TyrDC was specific to laminarin treatment, thus indicating that the regulation of TyrDC activity is critical for the accumulation of p-CO in potato tuber tissue.

Absolute structure of N-p-coumaroyloctopamine in elicitor-treated potato tuber tissue.

Treatment of potato tuber tissue with beta-1,3-oligoglucosaccharide causes an accumulation of N-p-coumaroyloctopamine (1). In order to determine the absolute structure of 1 in potato, optically active 1 was synthesized from (R)-octopamine which had been obtained from the racemic mixture by the fractional crystallization. By comparing the chromatographic behavior of synthetic and naturally-occurring samples with a chiral HPLC analysis, the absolute configuration of 1 in potato was determined to be S. This indicates that the absolute configuration of the octopamine moiety of 1 is opposite to that of octopamine formed in animal tissues.

Structure of the mutant fibrillin-1 gene in the tight skin (TSK) mouse.

Mice carrying the tight skin (TSK) mutation harbors a 3.0-kb genomic duplication (exons 17-40) of the fibrillin-1 gene (Fbn-1) located on band F of chromosome 2 as TSK mutation. We cloned and sequenced the mutated Fbn-1 gene, since it is believed to be responsible for TSK syndrome. Sequence analysis showed numerous amino acid differences in the 5' and 3' segments between the TSK mutation and wild-type fbn-1 gene, but any amino acid difference between the TSK mutation and C57BL/6 mice. (TSK and C57B1/6 mice are genetically similar, differing only by TSK mutation.) Four amino acid differences were observed between two copies of TSK's fbn-1 gene encoded by exons 17-40. Our results suggest that the majority of structural differences occurred in the N and C termini segments during strain divergence and only a few after the duplication event.