The disclosure relates to a the use of a composition comprising avian extract EP-2 in a therapeutically effective concentration together with a pharmaceutically acceptable carrier and/or diluent for treating or preventing proliferative skin disorders, cancers or pre-cancers. The avian extract EP-2 may be isolated from the tail feathers a bird of the order Psittaciformes (parrot), such as sulphur-crested cockatoo (Cacatua galerita), the galah (Cacatua roseicapilla), the Major Mitchell cockatoo (Cacatua leadbeateri leadbeateri) using an organic solvent. The proliferative skin disorder may be eczema (including atopic eczema, allergic contact dermatitis, infantile seborrhoeic eczema, adult seborrhoeic eczema, varicose eczema and discoid eczema), psoriasis (including chronic plaque syndrome, pustular psoriasis, erythrodermic psoriasis or nail psoriasis), and scarring including keloid scarring. The cancer or pre-cancer may be skin cancer (including basal cell carcinoma, squamous carcinoma or melanoma)； precancerous skin lesion (such as actinic or solar keratosis)； carcinomas (including breast, prostate. lung, pancreatic and colon cancers), sarcoma, lymphoma, germ cell tumour, blastoma, and leukaemia. The disclosure also relates to the use of a synthetic form of EP-2, comprising two or more of nicotinamide, 2,4-ditert butyl phenol, palmitic acid, oleic acid and squalene, for treating or preventing proliferative skin disorders, cancers or pre-cancers.
