ABSTRACT
INTRODUCTION: Psoriasis is a persistent chronic immune-mediated, relapsing, inflammatory and hyper proliferative skin disorder with genetic predisposition. Psoriasis can be considered as a T-cell mediated disease, with a complex role for a variety of cytokine interaction between keratinocytes and T-lymphocytes. Caspase-3 is an enzyme that plays a key role in apoptosis; it is a member of the family of cysteinyle aspartate specific proteases. AIM: To evaluate the expression of caspase-3 in Egyptian psoriasis patients and its role in apoptosis of keratinocytes. Also, to correlate this expression with the clinicopathological parameters in order to identify the possible hypothesized role of caspase-3 in the pathogenesis of psoriasis. MATERIALS AND METHODS: This was a case-control study conducted on patients suffering from chronic plaque psoriasis. A total of 20 psoriasis patients and 10 controls were selected from outpatient clinic of Dermatology, Menoufia University Hospital, between the period of October 2014 and January 2016. From each patient and control, a punch biopsy was taken. Evaluation of H&E stained sections and caspase-3 expression was done using standard immunohi-stochemical techniques. Non-parametric chi-square test, Mann-Whitney U test, Kruskal Wallis test and Spearman's coefficient test were the statistical tests used. RESULTS: High caspase-3 H score was significantly in favour of psoriatic group in comparison with the control group. On the contrary, in the dermis, caspase-3 was significantly higher in skin adnexa while completely absent in the psoriatic group. Strong caspase-3 expression was significantly in favour of high PASI score, early onset lesions and lesions in the extremities. Significant positive correlation was found between caspase-3 percent and PASI score (r= +0.53, p-value=0.03). CONCLUSION: Caspase-3 over expression in the psoriatic lesion proposes a potential role in the pathogenesis of psoriasis. Positive correlation between the caspase-3 expression and the early onset psoriatic lesion located in the extremities implies a possible poor prognostic impact of caspase-3 over expression.
