Serum 25-Hydroxyvitamin D Concentrations ≥40 ng/ml Are Associated with >65% Lower Cancer Risk: Pooled Analysis of Randomized Trial and Prospective Cohort Study

BackgroundHigher serum 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with a lower risk of multiple cancer types across a range of 25(OH)D concentrations.ObjectivesTo investigate whether the previously reported inverse association between 25(OH)D and cancer risk could be replicated, and if a 25(OH)D response region could be identified among women aged 55 years and older across a broad range of 25(OH)D concentrations.MethodsData from two cohorts representing different median 25(OH)D concentrations were pooled to afford a broader range of 25(OH)D concentrations than either cohort alone: the Lappe cohort (N = 1,169), a randomized clinical trial cohort (median 25(OH)D = 30 ng/ml) and the GrassrootsHealth cohort (N = 1,135), a prospective cohort (median 25(OH)D = 48 ng/ml). Cancer incidence over a multi-year period (median: 3.9 years) was compared according to 25(OH)D concentration. Kaplan-Meier plots were developed and the association between 25(OH)D and cancer risk was examined with multivariate Cox regression using multiple 25(OH)D measurements and spline functions. The study included all invasive cancers excluding skin cancer.ResultsAge-adjusted cancer incidence across the combined cohort (N = 2,304) was 840 cases per 100,000 person-years (1,020 per 100,000 person-years in the Lappe cohort and 722 per 100,000 person-years in the GrassrootsHealth cohort). Incidence was lower at higher concentrations of 25(OH)D. Women with 25(OH)D concentrations ≥40 ng/ml had a 67% lower risk of cancer than women with concentrations <20 ng/ml (HR = 0.33, 95% CI = 0.12–0.90).Conclusions25(OH)D concentrations ≥40 ng/ml were associated with substantial reduction in risk of all invasive cancers combined.     

Identification and inhibition of carbonic anhydrases from nematodes

Abstract

Carbonic anhydrases (CAs) are metalloenzymes, and classified into the evolutionarily distinct α, β, γ, δ, ζ, and η classes. α-CAs are present in many living organisms. β- and γ-CAs are expressed in most prokaryotes and eukaryotes, except for vertebrates. δ- and ζ-CAs are present in phytoplanktons, and η-CAs have been found in Plasmodium spp. Since the identification of α- and β-CAs in Caenorhabditis elegans, the nematode CAs have been considered as an emerging target in research focused on antiparasitic CA inhibitors. Despite the presence of α-CAs in both helminths and vertebrates, structural studies have revealed different kinetic and inhibition results. Moreover, lack of β-CAs in vertebrates makes this enzyme as an attractive target for inhibitory studies against helminthic infection. Some CA inhibitors, such as sulfonamides, have been evaluated against nematode CAs. This review article aims to present comprehensive information about the nematode CAs and their inhibitors as potential anthelminthic drugs.     

Population genomic evidence for plant glacial survival in Scandinavia

Quaternary glaciations have played a major role in shaping the genetic diversity and distribution of plant species. Strong palaeoecological and genetic evidence supports a postglacial recolonization of most plant species to northern Europe from southern, eastern and even western glacial refugia. Although highly controversial, the existence of small in situ glacial refugia in northern Europe has recently gained molecular support. We used genomic analyses to examine the phylogeography of a species that is critical in this debate. Carex scirpoidea Michx subsp. scirpoidea is a dioecious, amphi‐Atlantic arctic–alpine sedge that is widely distributed in North America, but absent from most of Eurasia, apart from three extremely disjunct populations in Norway, all well within the limits of the Weichselian ice sheet. Range‐wide population sampling and variation at 5,307 single nucleotide polymorphisms show that the three Norwegian populations comprise unique evolutionary lineages divergent from Greenland with high between‐population divergence. The Norwegian populations have low within‐population genetic diversity consistent with having experienced genetic bottlenecks in glacial refugia, and host private alleles that probably accumulated in long‐term isolated populations. Demographic analyses support a single, pre‐Weichselian colonization into Norway from East Greenland, and subsequent divergence of the three populations in separate refugia. Other refugial areas are identified in North‐east Greenland, Minnesota/Michigan, Colorado and Alaska. Admixed populations in British Columbia and West Greenland indicate postglacial contact. Taken together, evidence from this study strongly indicates in situ glacial survival in Scandinavia.     

Determination of ciclosporin A and its six main metabolites in isolated T-lymphocytes and whole blood using liquid chromatography-tandem mass spectrometry

A specific and sensitive method for determination of intracellular ciclosporin A (CsA) and its six main metabolites AM1, AM9, AM1c, AM1c9, AM19 and AM4N, in isolated T-lymphocytes and whole blood is described. T-lymphocytes were separated from whole blood using Prepacyte. The analytes were extracted and purified from isolated lymphocytes and whole blood by protein precipitation followed by solid-phase extraction (SPE). The analytes and the internal standard, ciclosporin C (CsC), were separated on a reversed phase C8 column (30 mm x 2.1mm, 3 microm) with a 10 mm x 2 mm, 5 microm Drop-In Guard Cartridge, using gradient elution chromatography and tandem ion trap mass spectrometry detection. The method has been validated in accordance with FDA guidelines and showed linear range from 0.25 to 500 ng/mL for CsA, 0.5 to 500 ng/mL for AM1, AM9 and AM19, 1 to 500 ng/mL for AM4N, AM1c and AM1c9 in intracellular matrix, and 2.5 to 3000 ng/mL for all analytes in whole blood. The applicability of the method is shown on patient samples.     

Comparative proteome profiling and functional analysis of chronic myelogenous leukemia cell lines

The aim of the present study was the molecular profiling of different Ph+ chronic myelogenous leukemia (CML) cell lines (LAMA84, K562, and KCL22) by a proteomic approach. By employing two-dimensional gel electrophoresis combined with mass spectrometry analysis, we have identified 191 protein spots corresponding to 142 different proteins. Among these, 63% were cancer-related proteins and 74% were described for the first time in leukemia cells. Multivariate analysis highlighted significant differences in the global proteomic profile of the three CML cell lines. In particular, the detailed analysis of 35 differentially expressed proteins revealed that LAMA84 cells preferentially expressed proteins associated with an invasive behavior, while K562 and KCL22 cells preferentially expressed proteins involved in drug resistance. These data demonstrate that these CML cell lines, although representing the same pathological phenotype, show characteristics in their protein expression profile that suggest different phenotypic leukemia subclasses. These data contribute a new potential characterization of the CML phenotype and may help to understand interpatient variability in the progression of disease and in the efficacy of a treatment.     

In situ proteolysis for protein crystallization and structure determination

We tested the general applicability of in situ proteolysis to form protein crystals suitable for structure determination by adding a protease (chymotrypsin or trypsin) digestion step to crystallization trials of 55 bacterial and 14 human proteins that had proven recalcitrant to our best efforts at crystallization or structure determination. This is a work in progress; so far we determined structures of 9 bacterial proteins and the human aminoimidazole ribonucleotide synthetase (AIRS) domain.