C Gutierrez-Steil, T Wrone-Smith, X Sun, J G Krueger, T Coven, B J Nickoloff
J Clin Invest.
1998;
101(1):33–39
doi:10.1172/JCI1165
This article Copyright © 1998, The American Society for Clinical Investigation
Abstract
|
Full text
|
PDF
T
he skin is constantly exposed to sunlight and frequently develops sun-induced skin cancers such as basal cell carcinoma (BCC). These epidermal-derived tumors escape local immune surveillance and infiltrate the dermis, requiring surgical removal. We report here that in contrast to keratinocytes in normal skin (n = 4), BCC tumor cells (n = 6) strongly and diffusely express Fas ligand (CD95L), but not Fas antigen (CD95). This CD95L expression in vivo by BCC tumor cells is associated with peritumoral T lymphocytes that are undergoing apoptosis. Moreover, CD95L can be induced on normal cultured keratinocytes after exposure to ultraviolet-B light (UV-B) irradiation. This induction of CD95L was confirmed at the mRNA and protein levels using multipassaged human keratinocytes and a keratinocyte cell line. Keratinocytes induced to express CD95L acquired the functional capacity to kill a CD95-positive lymphocyte cell line. Whereas hyperplastic keratinocytes in untreated psoriatic plaques do not express CD95L on their plasma membrane, after UV-B treatment there is strong and diffuse keratinocyte CD95L expression that coincided in a temporal fashion with depletion of intraepidermal T cells in all five patients studied. Our data suggest a novel molecular pathway by which UV light can contribute to the ability of a skin cancer to escape from immune attack by cytotoxic T lymphocytes, and a previously unrecognized therapeutic mechanism of action for UV-B light in psoriasis via keratinocyte CD95L expression. Such immunological events involving CD95L provide new insight and opportunity for novel treatment approaches not only for cutaneous neoplasms but also for various T cell-mediated dermatoses such as psoriasis.
This file is in Adobe Acrobat (PDF) format.
If you have not installed and configured the Adobe Acrobat Reader on your system.
Having trouble reading a PDF?
PDFs are designed to be printed out and read, but if you prefer to read them online, you may find it easier if you increase the view size to 125%.
Having trouble saving a PDF?
Many versions of the free Acrobat Reader do not
allow Save. You must instead save the PDF from the JCI Online page you downloaded it from. PC users:
Right-click on the Download link and choose the option that says something like "Save Link As...".
Mac users should hold the mouse button down on the link to get these same options.
Having trouble printing a PDF?
- Try printing one page at a time or to a newer printer.
- Try saving the file to disk before printing rather than opening it "on the fly." This requires that you
configure your browser to "Save" rather than "Launch Application" for the file type "application/pdf", and can
usually be done in the "Helper Applications" options.
- Make sure you are using the latest version of Adobe's Acrobat Reader.