Method and pharmaceutical composition for treating psoriasis, squamous cell carcinoma and/or parakeratosis by inhibiting expression of squamous cell carcinoma-related antigen

Abstract

In a first aspect thereof, the present invention provides a method for treatment and/or prevention of a disease selected from the group consisting of psoriasis and squamous cell carcinoma by inhibiting the expression of squamous cell carcinoma antigen (SCCA) by cells. In another aspect thereof, the present invention provides a method for screening for substances that inhibit epidermal parakeratosis, wherein the activity of a candidate substance that inhibits cysteine protease inhibitory activity possessed by squamous cell carcinoma antigen 1 (SCCA-1) is used as an indicator.

1 . A method for inhibiting epidermal parakeratosis by inhibiting caspase-14 inhibitory activity of SCCA-1 in epidermal cells to normalize epidermal cell keratization. 
     
     
         2 . The method according to  claim 1 , wherein caspase-14 inhibitory activity of SCCA-1 in epidermal cells is inhibited by applying to the skin a skin composition for external use containing as an active ingredient thereof one or a plurality of types of herbal medicines selected from the group consisting of cattail extract, grape extract, tomato extract, cucumber extract, kiwi extract and jujube extract. 
     
     
         3 . The method according to  claim 2 , wherein the skin composition for external use contains cattail extract.