PCP4 and Alzheimer disease: Interestingly, expression level changes of PEP-19 have been linked to several neurodegenerative conditions, such as Parkinson's disease [29], Alzheimer's disease [61] and Huntington's disease [32].javascript:void(0); Among the biological function studies of PEP-19, a study showing that PEP-19 can inhibit apoptotic cell death due to UV irradiation or treatment with staurosporine is of special interest [56].