Open AccessMonoclonal antibody specific for an activated RAS protein.
Author(s) -
Walter P. Carney,
D. Petit,
Peter Hamer,
Channing J. Der,
Toren Finkel,
Geoffrey M. Cooper,
M. Lefebvre,
H. Mobtaker,
Ronald A. DeLellis,
Arthur S. Tischler
Publication year - 1986
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.83.19.7485
Subject(s) - microbiology and biotechnology , monoclonal antibody , biology , transfection , amino acid , immunohistochemistry , antibody , cell culture , gene , peptide sequence , peptide , biochemistry , genetics , immunology
Activated RAS transforming genes that encode proteins (p21s) with amino acid substitutions at positions 12, 13, or 61 have been detected in 10-20% of human neoplasms. This report describes a monoclonal antibody (DWP) raised against a synthetic peptide corresponding to amino acids 5-16 of a mutated RAS gene encoding Val instead of Gly at position 12. DWP reacted in competition assays with peptides containing Val or Cys at position 12, but did not react with peptides containing Gly, Arg, Ser, Ala, Asp, or Glu at position 12. Immunoblot analysis of transformed NIH cells and human carcinoma cell lines showed that DWP reacts specifically with activated RAS proteins containing Val at position 12 and not with normal p21s or p21s activated by other amino acid substitutions at positions 12 and 61. Immunohistochemical studies showed that DWP-labeled transformed NIH cells and human carcinoma cells contained p21s with either Val or Cys at position 12 but not normal or other activated p21s. In contrast to the specificity seen with human carcinoma cell lines, analysis of formalin-fixed, primary carcinoma specimens indicated that positive immunoperoxidase staining with DWP did not necessarily correlate with immunoblot and transfection assays for the presence of activated RAS proteins. Immunohistochemical studies did show, however, that DWP preferentially binds human carcinoma cells.