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Upregulation of human β-defensin-3 and cathelicidin LL-37 in Kaposi's sarcoma.

ABSTRACT:

Background

Kaposi's sarcoma (KS) is a rare neoplasm of lymphatic endothelial cells. Human herpes virus 8 (HHV-8) is considered to be a necessary, but not sufficient causal agent of KS and additional cofactors remain unknown. In this study we evaluated the expression of human β defensin (HBD)-3 and LL-37 in cutaneous lesions of KS in comparison to the healthy skin of normal subjects.

Methods

We performed a quantitative immunohistochemical study of HBD-3 and LL-37 on skin lesions from 18 patients having KS, and on healthy skin from 12 normal controls.

Results

HBD-3 and LL-37 were significantly upregulated in epidermal and dermal specimens of all KS patients in comparison to normal skin of healthy controls. The immunostaining score of dermal HBD-3 was significantly higher in nodular lesions (9.6 ± 2.4) versus plaque lesions (4.1 ± 2.2), P = 0.001. Also the immunostaining score of dermal LL-37 was significantly higher in nodular lesions versus plaque lesions (P = 0.001).

Conclusions

We have demonstrated for the first time that HBD-3 and LL-37 are significantly upregulated in lesional skin of KS in comparison to the skin of healthy controls. The obtained data suggest a possible involvement of these antimicrobial peptides in the pathogenesis of KS. However, the biological significance of HBD-3 and LL-37 in KS lesions needs further research.

SUBMITTER: Fathy H

PROVIDER: S-EPMC3782342 | biostudies-literature |

REPOSITORIES: biostudies-literature

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