Osteopontin expression in chronic plaque psoriasis: an association with the severity of disease

OBJECTIVE

To explore the possible role of osteopontin (OPN) in chronic plaque psoriasis and understand the role of inflammation in psoriasis.

STUDY DESIGN

We investigated 36 patients with chronic plaque psoriasis using immunohistochemical technique for evaluation of OPN immunolocalization compared to normal skin biopsies of 10 normal subjects representing the control group.

RESULTS

OPN was expressed in the epidermis of all specimens, both in the psoriasis group and the control group without any significant differences except for the tendency of psoriatic lesions to show more cytoplasmic and nuclear pattern of OPN staining (55.56%) compared to normal skin (20%). Epidermal strong and diffuse immunostaining of OPN was associated with the severity of psoriasis, and there was a correlation of the intensity of OPN expression with the density of the dermal inflammatory infiltrate.

CONCLUSION

Our study suggests that OPN is involved in the pathophysiology of psoriasis, and a possible association with disease severity. OPN acts by different mechanisms through its expression by lesional keratinocytes, inflammatory cells, and endothelial cells. Nuclear localization of OPN may have a more significant role in the pathogenesis of psoriasis.

Diagnostic and prognostic role of galectin 3 expression in cutaneous melanoma

Many of the histopathologic criteria used to diagnose melanoma overlap with atypical but otherwise benign naevi such as dysplastic or Spitz naevi. Galectin-3 is a member of the galectin gene family and is expressed at elevated levels in a variety of neoplastic cell types. The aim of the present study was to investigate the diagnostic value of galectin-3 expression compared with homatropine methyle bromide-45(HMB-45) (one of the established and widely used immunohistochemical melanocytic markers) together with assessment of its prognostic value in melanoma lesions. This study was carried out on 21 cases of melanoma and 20 benign pigmented naevi. Galectin-3 was expressed in all the examined benign and malignant melanocytic lesions. The nucleocytoplasmic pattern of galectin-3 appeared in malignant cases only with 42.86% sensitivity, 100% specificity, and 70.73% accuracy. This pattern tended to be associated with thick melanoma (P = 0.08) and reduced survival (P = 0.22). The intensity of galectin-3 assessed by H-score was significantly of higher values in malignant lesions compared with benign lesions (P < 0.0001). The best cut-off value for discrimination between benign and malignant melanocytic lesions was 295 with 95% sensitivity, 70% specificity, and 83% accuracy. The diagnostic power of galectin-3 in distinguishing between benign and malignant melanocytic lesions relies on the pattern and the intensity of its expression. The nucleocytoplasmic pattern of galectin-3 expression carries greater probability of a malignant phenotype and a poor prognostic impact on patients' outcome.