The Use of Toll-like Receptor 4 Agonist to Reshape the Immune Signature in Ovarian Cancer.

BACKGROUND: Dendritic cell (DC) mono-immunotherapy has not been successful so far in ovarian cancer. The addition of a toll-like receptor (TLR) agonist has the potential to boost the innate immune system, in addition to the adoptive immune response initiated by DCs. MATERIALS AND METHODS: ID8-fLuc C57BL/6 mice were injected with DCs loaded with hypericin-based photodynamic therapy-treated tumor lysate. A TLR4 agonist [lipopolysaccharide (LPS)] was administered by different schedules). After two and three DC vaccinations, immune analysis was performed. RESULTS: There was no survival benefit from therapy with TLR4 agonist. Moreover, if LPS administrations started one week after tumor inoculation, the overall survival was even worse than that of untreated controls. Immune analyses revealed an intratumoral increase in natural killer cells and a decrease in regulatory T-cells, but an immunosuppressive signature in the ascites. CONCLUSION: Addition of LPS as an adjuvant to DC immunotherapy of ovarian cancer does not result in survival benefit.

New strategies of photoprotection.

Adequate photoprotection is essential to control UV-related disorders, including sunburn, photoaging and photocarcinogenisis. Sun avoidance, protection of skin with clothing, and sunscreens are presently the best way of photoprotection, assuming that they are used properly. However, new strategies, which are based on or make use of the endogenous protective response to UV light, may further improve currently used photoprotective means. The addition of repair enzymes and/or antioxidants has a positive effect on skin's recovery from UV-induced DNA-damage. Several botanical agents, mainly vitamins and polyphenols, have shown to influence signal transduction pathways leading to photoprotective effects. Also stimulation of endogenous UV-response pathways via irradiation with a low UV dose or via simulation of UV-induced DNA-damage results in photoprotective effects. Future research in this field and combination of different photoprotective strategies will hopefully lead to improved photoprotection.