Expression of human endogenous retrovirus K in melanomas and melanoma cell lines.
The human endogenous retrovirus K family (HERV-K) comprises 30 to 50 closely related proviruses, most of which are defective. In contrast to all other human endogenous retroviruses, some HERV-K proviruses have maintained open reading frames for all viral proteins. In addition to the structural proteins Gag and Env and the reverse transcriptase, two regulatory proteins (Rec and Np9) have been described. Malignant melanoma has the highest mortality among skin cancers and is particularly aggressive. To study the expression of HERV-K, a set of seven primers was developed that allows discrimination between full-length and spliced mRNA and mRNA from deleted and undeleted proviruses. Expression of full-length mRNA from deleted and undeleted proviruses was detected in all human cells investigated. Expression of spliced env and rec was detected in a teratocarcinoma cell line, in 45% of the metastatic melanoma biopsies, and in 44% of the melanoma cell lines. In normal neonatal melanocytes, spliced rec was detected but not spliced env. Viral proteins were shown to be expressed in primary melanomas, metastases, and melanoma cell lines by immunohistochemistry, immunofluorescence, and Western blot analyses using specific antisera. For the first time, antibodies against HERV-K were found in melanoma patients. Melanomas are, in addition to teratocarcinomas and human breast cancer, the third tumor type with enhanced expression of HERV-K.
Büscher
Kristina
K
Robert Koch-Institute and Department of Dermatology, Campus Charité-Mitte, Charité-University Medicine Berlin, Berlin, Germany.
Trefzer
Uwe
U
Hofmann
Maja
M
Sterry
Wolfram
W
Kurth
Reinhard
R
Denner
Joachim
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000097:blood / Q000276:immunology; D000918:Antibody Specificity; D045744:Cell Line, Tumor; D020077:Endogenous Retroviruses / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000097:blood / Q000821:virology*; D008875:Middle Aged; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012367:RNA, Viral / Q000096:biosynthesis / Q000235:genetics; D014763:Viral Matrix Proteins / Q000096:biosynthesis / Q000235:genetics
D000914:Antibodies, Viral; D012333:RNA, Messenger; D012367:RNA, Viral; D014763:Viral Matrix Proteins