Combining systemic retinoids with biologic agents for moderate to severe psoriasis.

BACKGROUND: Moderate to severe psoriasis, which is defined as psoriasis affecting more than 20% of the body surface area, often requires a combination of therapies to achieve remission. Although numerous data exist regarding the use of acitretin and biologic agent therapy alone for psoriasis, little is known about the efficacy, safety, and tolerability of acitretin combined with biologic agents. METHODS: Fifteen patients with psoriasis treated with concomitant acitretin and a biologic agent were identified, and their charts were reviewed for response to therapy, additional therapy necessary for disease management, side-effects, and laboratory abnormalities whilst on combination therapy. The Institutional Review Board did not require approval for this chart review. RESULTS: Twenty-nine per cent of patients showed clearance of psoriasis, 43% of patients showed an improvement of 90%, 14% showed an improvement of 75%, and 7.1% showed no change. During treatment with acitretin and biologic agent, five patients required no adjunctive treatment. Three patients were able to stop narrow-band ultraviolet-B (UV-B) therapy after an average of 2.33 months of combination therapy. Only one patient continued to require phototherapy (UV-B) in addition to the biologic agent. Three patients developed squamous cell carcinoma (SCC) whilst on combination therapy, but all patients had a previous history of SCC. One patient developed non-Hodgkin's lymphoma after 3 years of etanercept and acitretin, and the etanercept was discontinued. CONCLUSIONS: Acitretin combined with biologic agents offers a promising method of managing refractory psoriasis. More research is needed to determine the long-term safety and efficacy of this combination.

Benzo[a]pyrene and its metabolites combined with ultraviolet A synergistically induce 8-hydroxy-2'-deoxyguanosine via reactive oxygen species.

We previously reported that benzo[a]pyrene (BaP) and UVA radiation synergistically induced oxidative DNA damage via 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation in vitro. The present study shows that microsomal BaP metabolites and UVA radiation potently enhance 8-OHdG formation in calf thymus DNA about 3-fold over the parent compound BaP. Utilization of various reactive oxygen species scavengers revealed that singlet oxygen and superoxide radical anion were involved in the 8-OHdG formation induced by microsomal BaP metabolites and UVA. Two specific BaP metabolites, benzo[a]pyrene-r-7,t-8-dihydrodiol-t-9,10-epoxide (+/-) (anti) (BPDE) and BaP-7,8-dione, were further tested for synergism with UVA. BaP-7,8-dione showed an effect on 8-OHdG formation induced by UVA radiation that was similar to that of the parent BaP, whereas BPDE exhibited significantly higher induction of 8-OHdG than BaP. At as low as 0.5 microM, BPDE plus UVA radiation substantially increased 8-OHdG levels about 25-fold over the parent BaP. BPDE increased the formation of 8-OHdG levels in both BPDE concentration- and UVA dose-dependent manners. Additionally, singlet oxygen was found to play a major role in 8-OHdG induction by BPDE and UVA. These results suggest that BaP metabolites such as BPDE synergize with UVA radiation to produce ROS, which in turn induce DNA damage.