The effects of gp100 and tyrosinase peptide vaccinations on nevi in melanoma patients.
BACKGROUND
A new approach to prevent disease recurrence in high-risk melanoma patients involves immunization with gp100 and tyrosinase peptides. This is the first study to examine the effects of such treatments on nevi.


METHODS
We studied biopsies of 'clinically atypical' nevi from 10 patients before and after peptide vaccination. All had a cutaneous melanoma measuring at least 1.5 mm in depth, satellite metastases, or at least one positive lymph node. We performed immunohistochemical stains for CD3, CD4, CD8, MHC-I, MHC-II, CD1a, HMB-45, MART-1, tyrosinase, bcl-2, p53, and Ki-67 (mib-1).


RESULTS
Immunohistochemistry showed no differences in staining due to vaccination in either the immunologic or melanocytic markers. However, there was a significant increase in both p53 and bcl-2 staining, and a trend toward decreased Ki-67 staining, in the nevi post-treatment.


CONCLUSIONS
The primary goal of peptide vaccinations with gp100 and tyrosinase is to activate melanoma-specific T cells in order to prevent melanoma recurrence. Nevi were studied in order to assess the effects on benign melanocytes. No significant changes in lymphocytes, langerhans cells, expression of MHC antigens, or melanocytic markers were found. The increase in p53 and bcl-2 raises the possibility that vaccination with melanocytic antigens stimulates a response in benign melanocytes.
Cassarino
David S
DS
Department of Pathology Stanford University Medical Center, CA 94305, USA. dcassarino@stanford.edu
Miller
Walter J
WJ
Auerbach
Aaron
A
Yang
Aparche
A
Sherry
Richard
R
Duray
Paul H
PH
D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D019496:Cancer Vaccines; D005260:Female; D006680:HLA Antigens / Q000187:drug effects; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008545:Melanoma / Q000517:prevention & control*; D008562:Membrane Glycoproteins / Q000276:immunology*; D008875:Middle Aged; D014442:Monophenol Monooxygenase / Q000276:immunology*; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D009506:Nevus / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000187:drug effects / Q000378:metabolism; D012878:Skin Neoplasms / Q000517:prevention & control*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000378:metabolism; D058951:gp100 Melanoma Antigen
D014408:Biomarkers, Tumor; D019496:Cancer Vaccines; D006680:HLA Antigens; D019394:Ki-67 Antigen; D008562:Membrane Glycoproteins; C548637:PMEL protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D058951:gp100 Melanoma Antigen; D014442:Monophenol Monooxygenase