Investigation of Cross-Reactivity of Anti-Ephrin-B2 Antibody to Other Ephrin-B Members in an Immunohistochemical Study in a Cohort of Oral Squamous Cell Carcinoma

Ephrin-B1,-B2 and -B3 proteins share a high degree of sequence similarity. Investigation these as putative prognostic markers in human cancers including oral squamous cell carcinoma (OSCC) has been limited by challenges generating specific antibodies against them. The current study examined the reactivity polyclonal anti-human ephrin-B2 antibody (HPA008999) ephrin-B investigated significance immunoreactivity same at different intra-tumor sites OSCC specimens. By amino acid comparison, immunocytochemistry Western blot analysis on lysates precipitates from HEK-293T cells transfected with EFNB1, EFNB2, or EFNB3 expression constructs, we demonstrated that HPA008999 reacted to all proteins. Using immunohistochemistry (IHC) cohort (n = 131) OSCC, showed tumor center, but not invading front, was significantly associated worse 5-year overall survival probabilities. In conclusion, center might be useful marker OSCC. These data underscore need for investigation cross-reactivity similar protein members obtaining reliable meaningful results IHC based biomarker studies.