The antibody MAB8051 directed against osteoprotegerin detects carbonic anhydrase II: implications for association studies with human cancers.
A commonly used monoclonal antibody targeting osteoprotegerin (OPG), MAB8051, detects a truncated protein species in breast and prostate cancer cell lysates. OPG expression has been reported to contribute to cell survival of both of these cancers. We hypothesised that the truncated protein represented a unique tumour-associated OPG isoform. However, here we show that the truncated protein identified by MAB8051 in cancer cell lines is carbonic anhydrase II (CA II), also implicated in tumour biology. We clearly demonstrate cross-reactivity of this OPG antibody in western blots. OPG and CA II RNA-interference studies confirmed the identity of the bands. We show almost identical staining patterns between MAB8051 and CA II immunohistochemistry of different human tissue types and human tumour types using serial sections. We conclude that care should be exercised using this antibody for immunohistochemistry studies, without additional in situ hybridisation, or parallel use of other OPG-specific antibodies.
Waterman
Elizabeth A
EA
Academic Unit of Urology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
Cross
Neil A
NA
Academic Unit of Urology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
Lippitt
Jenifer M
JM
Academic Unit of Urology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
Cross
Simon S
SS
Academic Unit of Pathology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
Rehman
Ishtiaq
I
Academic Unit of Urology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
Holen
Ingunn
I
Clinical Oncology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
Hamdy
Freddie C
FC
Academic Unit of Urology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
Eaton
Colby L
CL
Academic Unit of Urology, School of Medicine and Biomedical Sciences, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology*; D024402:Carbonic Anhydrase II / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009369:Neoplasms / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D053244:Osteoprotegerin / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics
D000911:Antibodies, Monoclonal; D053244:Osteoprotegerin; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D024402:Carbonic Anhydrase II