Effect of Aspirin on Cancer Chemoprevention in Japanese Patients With Type 2 Diabetes: 10-Year Observational Follow-up of a Randomized Controlled Trial

OBJECTIVE

This study analyzed the efficacy of low-dose aspirin in cancer chemoprevention in patients with diabetes.

RESEARCH DESIGN AND METHODS

This study was a posttrial follow-up of the Japanese Primary Prevention of Atherosclerosis with Aspirin for Diabetes (JPAD) trial. Participants in the JPAD trial (2,536 Japanese patients with type 2 diabetes and without preexisting cardiovascular disease) were randomly allocated to receive aspirin (81 or 100 mg daily) or no aspirin. After that trial ended in 2008, we followed up with the participants until 2015, with no attempt to change the previously assigned therapy. The primary end point was total cancer incidence. We investigated the effect of low-dose aspirin on cancer incidence.

RESULTS

During the median follow-up period of 10.7 years, a total of 318 cancers occurred. The cancer incidence was not significantly different between the aspirin and no-aspirin groups (log-rank, P = 0.4; hazard ratio [HR], 0.92; 95% CI, 0.73-1.14; P = 0.4). In subgroup analyses, aspirin did not affect cancer incidence in men, women, or participants aged ≥65 years. However, it decreased cancer incidence in participants aged <65 years (log-rank, P = 0.05; HR, 0.67; 95% CI, 0.44-0.99; P = 0.048). After adjusting for sex, hemoglobin A_1c, smoking status, and administration of metformin and statins, aspirin significantly reduced cancer incidence in participants aged <65 years (adjusted HR, 0.66; 95% CI, 0.43-0.99; P = 0.04).

CONCLUSIONS

Low-dose aspirin did not reduce cancer incidence in Japanese patients with type 2 diabetes.

The anti-inflammatory effect of 10-oxo-trans-11-octadecenoic acid (KetoC) on RAW 264.7 cells stimulated with Porphyromonas gingivalis lipopolysaccharide

BACKGROUND

There is rapidly developing interest into the role of several anti-inflammatory agents to resolve inflammation in periodontal disease. A bioactive polyunsaturated fatty acid, 10-oxo-trans-11-octadecenoic acid (KetoC), is known to have various beneficial physiological effects; however, the effect of KetoC on inflammation remains unclear. Here, we investigated the effect of KetoC on RAW 264.7 cells stimulated with Porphyromonas gingivalis lipopolysaccharide, and explored the intracellular mechanism responsible for its anti-inflammatory effects.

METHODS

RAW 264.7 cells were pre-treated with or without KetoC, and then stimulated with or without P. gingivalis lipopolysaccharide. Levels of tumor necrosis factor α (TNFα), interleukin (IL)-6 and IL-1β were determined by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Specific antagonists for G protein-coupled receptor (GPR)40 and GPR120 were used to clarify the receptor for KetoC. The intracellular mechanism was investigated using western blotting analysis to separate nuclear and cytosolic NF-κB p65 protein.

RESULT

KetoC (5 μmol/L) was not toxic to RAW 264.7 cells, and significantly reduced the expression of TNFα and IL-6 mRNA and protein, and IL-1β mRNA. No protein production of IL-1β was observed. Additionally, when bound to GPR120, KetoC trended to downregulate nuclear NF-κB p65 protein levels. However, the antagonist for GPR40 failed to diminish the action of KetoC.

CONCLUSION

KetoC suppressed the proinflammatory cytokines TNFα, IL-6 and IL-1β via NF-κB p65, by binding to its receptor GPR120. KetoC is a promising candidate in future studies as a bioactive anti-inflammatory agent in treating periodontal disease.

Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

Superconductivity at the Polar-Nonpolar Phase Boundary of SnP with an Unusual Valence State

Structural, magnetic, and electrical characterizations reveal that SnP with an unusual valence state (nominally Sn^{3+}) undergoes a ferroelectriclike structural transition from a simple NaCl-type structure to a polar tetragonal structure at approximately 250 K at ambient pressure. First-principles calculations indicate that the experimentally observed tetragonal distortion enhances the charge transfer from Sn to P, thereby making the polar tetragonal phase energetically more stable than the nonpolar cubic phase. Hydrostatic pressure is found to promptly suppress the structural phase transition in SnP, leading to the emergence of bulk superconductivity in a phase-competitive manner. These findings suggest that control of ferroelectriclike instability in a metal can be a promising way for creating novel superconductors.