Tyrosinase (Tyr) catalyzes hydroquinone (HQ) oxidation via two main pathways. The HBQ pathway directly oxidizes HQ to 2-hydroxy-1,4-benzoquinone (HBQ), which dimerizes and forms hydroquinone-eumelanin (HQ-EM). The BQ pathway involves dopaquinone (DQ)-mediated redox exchange producing p-benzoquinone (BQ), which reacts with cysteine (Cys) to form 2-S-cysteinylhydroquinone (Cys-HQ) and further oxidizes to hydroquinone-pheomelanin (HQ-PM). These pathways illustrate the enzymatic formation of...

A registry study from Lund University in Sweden shows a possible increased risk of basal cell carcinoma with certain blood pressure medications. Because the risk increase is relatively low, 9% or lower, the researchers do not recommend treatment discontinuation. Instead, physicians should inform their patients that extra sun protection may be needed. The study’s lead author, Johan Kappelin, PhD, is a senior consultant at the dermatology clinic in Landskrona, Sweden. “Basal cell carcinoma is...

Durable, ongoing near-complete response to nivolimab + relatlimab in a 64-year-old with locally-advanced BCC after resistance to 26 weeks of nivolimab alone. Photo by: Evan Lipson, M.D. A new study led by researchers at the Johns Hopkins Kimmel Cancer Center found that patients with advanced basal cell carcinoma (BCC) may benefit from receiving immunotherapy earlier in treatment. Results from the phase 2 clinical trial (NCT03521830), presented Oct. 20 at the European Society for Medical...