TY - JOUR
T1 - Prostate cancer progression correlates with increased humoral immune response to a human endogenous retrovirus GAG protein
AU - Reis, Bernardo Sgarbi
AU - Jungbluth, Achim A.
AU - Frosina, Denise
AU - Holz, Megan
AU - Ritter, Erika
AU - Nakayama, Eiichi
AU - Ishida, Toshiaki
AU - Obata, Yuichi
AU - Carver, Brett
AU - Scher, Howard
AU - Scardino, Peter T.
AU - Slovin, Susan
AU - Subudhi, Sumit K.
AU - Reuter, Victor E.
AU - Savage, Caroline
AU - Allison, James P.
AU - Melamed, Jonathan
AU - Jäager, Elke
AU - Ritter, Gerd
AU - Old, Lloyd J.
AU - Gnjatic, Sacha
PY - 2013/11/15
Y1 - 2013/11/15
N2 - Purpose: Human endogenous retroviruses (HERV) encode 8% of the human genome. While HERVs may play a role in autoimmune and neoplastic disease, no mechanistic association has yet been established. We studied the expression and immunogenicity of a HERV-K GAG protein encoded on chromosome 22q11.23 in relation to the clinical course of prostate cancer. Experimental Design: In vitro expression of GAG-HERV-K was analyzed in panels of normal and malignant tissues, microarrays, and cell lines, and effects of demethylation and androgen stimulation were evaluated. Patient sera were analyzed for seroreactivity to GAG-HERV-K and other self-antigens by ELISA and seromics (protein array profiling). Results: GAG-HERV-K expression was most frequent in prostate tissues and regulated both by demethylation of the promoter region and by androgen stimulation. Serum screening revealed that antibodies to GAG-HERV-K are found in a subset of patients with prostate cancer (33 of 483, 6.8%) but rarely in male healthy donors (1 of 55, 1.8%). Autoantibodies to GAG-HERV-K occurred more frequently in patients with advanced prostate cancer (29 of 191 in stage III-IV, 21.0%) than in early prostate cancer (4 of 292 in stages I-II, 1.4%). Presence of GAG-HERV-K serum antibody was correlated with worse survival of patients with prostate cancer, with a trend for faster biochemical recurrence in patients with antibodies to GAG-HERV-K. Conclusions: Preferential expression of GAG-HERV-K ch22q11.23 in prostate cancer tissue and increased frequency of autoantibodies observed in patients with advanced prostate cancer make this protein one of the first bona fide retroviral cancer antigens in humans, with potential as a biomarker for progression and biochemical recurrence rate of prostate cancer.
AB - Purpose: Human endogenous retroviruses (HERV) encode 8% of the human genome. While HERVs may play a role in autoimmune and neoplastic disease, no mechanistic association has yet been established. We studied the expression and immunogenicity of a HERV-K GAG protein encoded on chromosome 22q11.23 in relation to the clinical course of prostate cancer. Experimental Design: In vitro expression of GAG-HERV-K was analyzed in panels of normal and malignant tissues, microarrays, and cell lines, and effects of demethylation and androgen stimulation were evaluated. Patient sera were analyzed for seroreactivity to GAG-HERV-K and other self-antigens by ELISA and seromics (protein array profiling). Results: GAG-HERV-K expression was most frequent in prostate tissues and regulated both by demethylation of the promoter region and by androgen stimulation. Serum screening revealed that antibodies to GAG-HERV-K are found in a subset of patients with prostate cancer (33 of 483, 6.8%) but rarely in male healthy donors (1 of 55, 1.8%). Autoantibodies to GAG-HERV-K occurred more frequently in patients with advanced prostate cancer (29 of 191 in stage III-IV, 21.0%) than in early prostate cancer (4 of 292 in stages I-II, 1.4%). Presence of GAG-HERV-K serum antibody was correlated with worse survival of patients with prostate cancer, with a trend for faster biochemical recurrence in patients with antibodies to GAG-HERV-K. Conclusions: Preferential expression of GAG-HERV-K ch22q11.23 in prostate cancer tissue and increased frequency of autoantibodies observed in patients with advanced prostate cancer make this protein one of the first bona fide retroviral cancer antigens in humans, with potential as a biomarker for progression and biochemical recurrence rate of prostate cancer.
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U2 - 10.1158/1078-0432.CCR-12-3580
DO - 10.1158/1078-0432.CCR-12-3580
M3 - Article
C2 - 24081977
AN - SCOPUS:84888108951
SN - 1078-0432
VL - 19
SP - 6112
EP - 6125
JO - Clinical Cancer Research
JF - Clinical Cancer Research
IS - 22
ER -