Pre-Clinical Evidence for the Efficacy of Tryptanthrin as a Potent Suppressor of Skin Cancer

The study demonstrated that tryptanthrin, a compound from indigo naturalis, was effective in suppressing non-melanoma skin cancer (NMSC) in pre-clinical models using Swiss albino mice. Tryptanthrin reduced tumor size by 60.1% and tumor multiplicity by 59% when applied topically, and delayed tumor onset with only 20% incidence at 7 weeks compared to 100% in untreated mice. It inhibited hair follicle cell proliferation by suppressing β-catenin activation and reduced inflammation without harming normal skin. The study involved 12 animals in the untreated group and 10-12 in the treated groups. Tryptanthrin also showed significant cytotoxicity against human epidermoid carcinoma cells while being non-toxic to normal skin cells, suggesting its potential as a non-toxic therapeutic agent for NMSC and recommending it for clinical trials.