TLDR  Cornification is how skin cells die to form the protective outer layer of skin, hair, and nails.   
  The document reviewed the process of cornification, a unique form of programmed cell death in keratinocytes essential for forming the skin barrier, hair, and nails. It highlighted the roles of various enzymes, including caspase-14, DNase1L2, and cathepsins, in the differentiation and maturation of keratinocytes. The review emphasized the anti-apoptotic and anti-necrotic mechanisms that prevent premature cell death, ensuring a resilient and interconnected barrier. Despite advances, many mechanistic aspects of keratinocyte death during cornification remained unclear, underscoring the need for further research to fully understand this complex process and its implications for skin conditions and cancer.
                     186 citations
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  December 2012   in “Current opinion in cell biology”    Keratin proteins are increasingly recognized as important for cell health and are linked to many diseases.  
     
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  September 2011   in “Human molecular genetics online/Human molecular genetics”    New treatments targeting specific genes show promise for treating keratin disorders.  
     
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  April 2011   in “International journal of legal medicine”    In situ DNA labeling in hair can help predict forensic DNA analysis success.  
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  August 2008   in “The journal of investigative dermatology/Journal of investigative dermatology”    TGase 3 helps build hair structure by forming strong bonds between proteins.  
     
           100 citations
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  March 2006   in “Journal of biological chemistry/The Journal of biological chemistry”    Cystatin M/E strongly inhibits cathepsin V and cathepsin L, important for skin formation.  
               425 citations
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  August 2002   in “BioEssays”    The cornified cell envelope forms a protective barrier in skin and hair, using specific proteins and lipids to maintain effectiveness.  
     
           146 citations
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  May 2002   in “The American journal of pathology”    Cathepsin L is essential for normal hair growth and development.  
     
           1113 citations
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  August 1999   in “The New England Journal of Medicine”    Hair follicle biology advancements may lead to better hair growth disorder treatments.  
    
   
        
       
    Cornification is the process where living skin cells die to create a protective barrier, and problems with it can cause skin diseases.  
     
           3 citations
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  September 2005   in “Experimental dermatology”    The cornified envelope is crucial for skin's barrier function and involves key proteins and genetic factors.  
     
           12 citations
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  August 2022   in “Biochemical Journal”    Different types of cell death affect skin health and inflammation, and understanding them could improve treatments for skin diseases.  
               8 citations
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  January 2023   in “International journal of molecular sciences”    Transglutaminase activity is important for skin and is found in both mammals and birds.  
               68 citations
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  April 2014   in “Journal of Investigative Dermatology”    Trichohyalin-like proteins are essential for the development of skin structures like hair, nails, and feathers.