Genetic variant of cyclooxygenase-2 in gastric cancer: More inflammation and susceptibility.

Gastric cancer accounts for the majority cancer-related deaths worldwide. Although various methods have considerably improved the screening, diagnosis, and treatment of gastric cancer, its incidence is still high in Asia, and the 5-year survival rate of advanced gastric cancer patients is only 10%-20%. Therefore, more effective drugs and better screening strategies are needed for reducing the incidence and mortality of gastric cancer. Cyclooxygenase-2 (COX-2) is considered to be the key inducible enzyme in prostaglandins (PGs) synthesis, which is involved in multiple pathways in the inflammatory response. For example, inflammatory cytokines stimulate innate immune responses via Toll-like receptors and nuclear factor-kappa B to induce COX-2/PGE2 pathway. In these processes, the production of an inflammatory microenvironment promotes the occurrence of gastric cancer. Epidemiological studies have also indicated that non-steroidal anti-inflammatory drugs can reduce the risk of malignant tumors of the digestive system by blocking the effect of COX-2. However, clinical use of COX-2 inhibitors to prevent or treat gastric cancer may be limited because of potential side effects, especially in the cardiovascular system. Given these side effects and low treatment efficacy, new therapeutic approaches and early screening strategies are urgently needed. Some studies have shown that genetic variation in COX-2 also play an important role in carcinogenesis. However, the genetic variation analysis in these studies is incomplete and isolated, pointing out only a few single nucleotide polymorphisms (SNPs) and the risk of gastric cancer, and no comprehensive study covering the whole gene region has been carried out. In addition, copy number variation (CNV) is not mentioned. In this review, we summarize the SNPs in the whole COX-2 gene sequence, including exons, introns, and both the 5' and 3' untranslated regions. Results suggest that COX-2 does not increase its expression through the CNV and the SNPs in COX-2 may serve as the potential marker to establish risk stratification in the general population. This review synthesizes emerging insights of COX-2 as a biomarker in multiple studies, summarizes the association between whole COX-2 sequence variation and susceptibility to gastric cancer, and discusses the future prospect of therapeutic intervention, which will be helpful for early screening and further research to find new approaches to gastric cancer treatment.

4-Di-phenyl-phosphanyl-8-methyl-1,5-naphthyridine.

In the title compound, C21H17N2P, the dihedral angles between the 1,5-naphthyridine ring system (r.m.s. deviation = 0.005 Å) and the phenyl rings are 89.18 (8) and 77.39 (8)°. The phenyl rings are almost perpendicular, making a dihedral angle of 88.12 (8)°. The only possible inter-molecular inter-action is a very weak aromatic π-π stacking inter-action [centroid-centroid separation = 3.898 (2) Å].

Novel multifunctional organic semiconductor materials based on 4,8-substituted 1,5-naphthyridine: synthesis, single crystal structures, opto-electrical properties and quantum chemistry calculation.

A series of 4,8-substituted 1,5-naphthyridines (1a-1h) have been successfully synthesised by a Suzuki cross-coupling between 4,8-dibromo-1,5-naphthyridine (4) and the corresponding boronic acids (2a-2h) in the presence of catalytic palladium acetate in yields of 41.4-75.8% and have ben well characterized. They are thermally robust with high phase transition temperatures (above 186 °C). Compounds 1b, 1e and 1f crystallized in the monoclinic crystal system with the space groups P2(1)/c, P2(1)/c and P2(1)/n, respectively. All of them show the lowest energy absorption bands (λ(max)(Abs): 294-320 nm), revealing low optical band gaps (2.77-3.79 eV). These materials emit blue fluorescence with λ(max)(Em) ranging from 434-521 nm in dilute solution in dichloromethane and 400-501 nm in the solid state. 4,8-Substituted 1,5-naphthyridines 1a-1h have estimated electron affinities (EA) of (2.38-2.72 eV) suitable for electron-transport materials and ionization potentials (IP) of 4.85-5.04 eV facilitate excellent hole-injecting/hole-transport materials properties. Quantum chemical calculations using DFT B3LYP/6-31G* showed nearly identical the lowest unoccupied molecular orbitals (LUMO) of -2.39 to -2.19 eV and the highest occupied molecular orbitals (HOMO) of -5.33 to -6.84 eV. These results demonstrate the 4,8-substituted 1,5-naphthyridines 1a-1h with a simple architecture might be promising blue-emitting (or blue-green-emitting) materials, electron-transport materials and hole-injecting/hole-transport materials for applications for developing high-efficiency OLEDs.