Influence of phototherapy in psoriasis on ki-67 antigen expression: a preliminary study

Abstract

Antigen Ki-67 is a non-histone nuclear protein, closely connected with cell proliferation. Determining Ki-67 allows for a quick and reliable evaluation of the growth fraction of the studied cell population. It serves as a marker of proliferative activity in neoplasms and other diseases with excessive cell proliferation such as psoriasis. Evaluation of Ki-67 expression in epidermal cells was performed in 10 individuals suffering from plaque psoriasis, before and after one of three methods of phototherapy: broadband UVB, narrowband UVB or PUVA. We observed increased Ki-67 antigen expression in psoriatic lesions. The percentage of Ki-67 positive nuclei in the epidermis affected by the disease ranged from 0 to 30% and in the macroscopically healthy surrounding tissue the percentage was from 0 to 10%. After phototherapy the expression in lesional skin decreased (p < 0.01). The greatest decrease was observed after the application of PUVA therapy (from 25 to 10% of cells, p < 0.05). No significant differences were observed in the perilesional skin with regard to Ki-67 antigen expression before or after phototherapy. On the basis of our own study and studies conducted by other researchers, it can be concluded that reduced Ki-67 expression after the application of PUVA and UVB therapies in the psoriatic epidermis is not a characteristic result of phototherapy only. It is a characteristic property of any effective psoriasis therapy.

Evaluation of IHC Ki-67 with Clinical Correlation in Psoriasis

“…PASI score is a universally accepted clinical indica-tor of disease severity in plaque type psoriasis. We studied plaque patients with PASI score ranging from 5.2 to 44.2 (mean 18.32) and found significantly higher Ki-67 expression in patients with PASI more than 10 as compared to those with PASI under 10, which is consistent with the findings of authors who have noted a positive correlation between clinical psoriatic activity (PASI) and epidermal proliferative activity (17,18). According to the European S3 Guidelines on the systemic treatment of psoriasis vulgaris, moderate to severe disease is defined as a PASI score >10 and is an indication for systemic treatment (19).…”

The Pathophysiological Mechanisms and the Quest for Biomarkers in Psoriasis, a Stress-Related Skin Disease

“…Ki67 is a marker of cell proliferation and is therefore found in high levels in psoriatic lesions [ 108 ]. Some authors showed that Ki67 expression decreases after therapy [ 109 ].…”

Forsythoside A Alleviates Imiquimod-Induced Psoriasis-like Dermatitis in Mice by Regulating Th17 Cells and IL-17A Expression

“…Another study showed that Ki-67 is a feasible marker of proliferation in the initial phase of adult neurogenesis [27]. Furthermore, previous studies have claimed that reduced Ki-67 expression was discovered after different kinds of treatment were applied to psoriatic skin lesions [28,29]. In this study, the results showed reduced Ki-67 expression after treatment with forsythoside A, implying that it inhibits epidermal proliferation in psoriatic skin lesions.…”