Abstract LB-450: Gene expression of colonic submucosa differs between the inflammatory colitides. A possible reason for differences in IBD-associated CRC incidences

Abstract Purpose: Differentiating ulcerative colitis (UC) and Crohn's colitis (CC) may be inaccurate in up to 30% of inflammatory bowel disease (IBD) cases due to overlapping features of these colitides. IBD-associated colorectal cancer (CRC) is frequently diagnosed in an advanced stage. Mass-spectrometric (MS) proteomic patterns found in colonic submucosa have been shown to discriminate UC and CC. To verify this, we aimed to conduct pilot gene expression analyses via microarray assessment of colonic submucosa. The significances of these genes to CRC initiation is as yet not been elucidated. Methods: Laser capture microdissection of colonic submucosa from UC (n=8), CC (n=8), and normal (NL, n=8) samples was performed. The submucosal mRNA was extracted using the PicoPure(TM) RNA Isolation Kit. Comprehensive gene expression analysis of the pooled mRNA from each group was then performed using the Affymetrix GeneChip® Gene 1.0 ST Array System. To detect changes for UC, we compared UC to CC and UC to NL; and for CC, we compared CC to UC and CC to NL. Results: 28,869 genes were represented on the array by 26 probes spread across the full length of each gene. When comparing UC to CC, 138 genes showed at least a 5-fold significant overexpression (p<0.01) with 5 of these genes showing a greater than 30-fold overexpression (Table, all p<0.0001). When comparing CC to UC, 5 different genes were overexpressed at greater than 30-fold change (Table, all p<0.0001). The results of the comparisons of these highly overexpressed genes in UC and CC vs. NL is noted in Table. Conclusions: Microarray assessments show significantly different gene overexpression in UC and CC colonic submucosa, with a few select genes showing dramatic overexpression. Preliminary results indicate that we have the tools in hand to successfully validate the results from the microarray analysis using TR-qPCR and immunohistochemistry (IHC). These genes may assist in delineation of the previously identified differentiating MS submucosal proteomic peaks, potentially facilitating protein biomarker identification to discriminate the inflammatory colitides. These genes may relate to CRC initiation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-450. doi:10.1158/1538-7445.AM2011-LB-45

Structural, Electronic, and Magnetic Properties of Quasi-1D Quantum Magnets [Ni(HF2)(pyz)(2)]X (pyz = pyrazine; X = PF6-, SbF6-) Exhibiting Ni-FHF-Ni and Ni-pyz-Ni Spin Interactions

[Ni(HF(2))(pyz)(2)]X {pyz = pyrazine; X = PF(6)(-) (1), SbF(6)(-) (2)} were structurally characterized by synchrotron X-ray powder diffraction and found to possess axially compressed NiN(4)F(2) octahedra. At 298 K, 1 is monoclinic (C2/c) with unit cell parameters, a = 9.9481(3), b = 9.9421(3), c = 12.5953(4) Å, and β = 81.610(3)° while 2 is tetragonal (P4/nmm) with a = b = 9.9359(3) and c = 6.4471(2) Å and is isomorphic with the Cu-analogue. Infinite one-dimensional (1D) Ni-FHF-Ni chains propagate along the c-axis which are linked via μ-pyz bridges in the ab-plane to afford three-dimensional polymeric frameworks with PF(6)(-) and SbF(6)(-) counterions occupying the interior sites. A major difference between 1 and 2 is that the Ni-F-H bonds are bent (∼157°) in 1 but are linear in 2. Ligand field calculations (LFT) based on an angular overlap model (AOM), with comparison to the electronic absorption spectra, indicate greater π-donation of the HF(2)(-) ligand in 1 owing to the bent Ni-F-H bonds. Magnetic susceptibility data for 1 and 2 exhibit broad maxima at 7.4 and 15 K, respectively, and λ-like peaks in dχT/dT at 6.2 and 12.2 K that are ascribed to transitions to long-range antiferromagnetic order (T(N)). Muon-spin relaxation and specific heat studies confirm these T(N)'s. A comparative analysis of χ vs T to various 1D Heisenberg/Ising models suggests moderate antiferromagnetic interactions, with the primary interaction strength determined to be 3.05/3.42 K (1) and 5.65/6.37 K (2). However, high critical fields of 19 and 37.4 T obtained from low temperature pulsed-field magnetization data indicate that a single exchange constant (J(1D)) alone is insufficient to explain the data and that residual terms in the spin Hamiltonian, which could include interchain magnetic couplings (J(⊥)), as mediated by Ni-pyz-Ni, and single-ion anisotropy (D), must be considered. While it is difficult to draw absolute conclusions regarding the magnitude (and sign) of J(⊥) and D based solely on powder data, further support offered by related Ni(II)-pyz compounds and our LFT and density-functional theory (DFT) results lead us to a consistent quasi-1D magnetic description for 1 and 2