In this investigation, our attention was focused on two potential tumor-associated antigens, namely, Zuotin-related factor 1 (ZRF1) and R motif-containing protein 1 (KRR1), previously identified by SEREX analysis of medullary breast carcinoma cDNA library [12, 15].
Totally, 4 SEREX clones NY-SCLC-6, NY-BR-13, NGO-St-58 5', and UL-CML-1 have been identified by screening of cDNA libraries from lung, breast, and stomach cancers and leukemia correspondingly (Table 5).
Analysis of Sequences of SEREX Clones Identified from Different Tumors, Which Encode ZRF1 Antigen.
Obtained data indicate that at least three SEREX clones KY-MBC 29-88-1, NGO-St-58, and NY-BR-13 correspond to different mRNA transcripts of DNAJC2 gene, which encode in turn two different protein isoforms (Table 6).
Previously, we have described 81 autoantigens identified from breast, colon, and thyroid cancers by SEREX approach [10, 12, 13, 15, 16].
This concordance was explained by Greiner in part by different cDNAs lengths of SEREX clones that might result in a various conformation of the gene's protein products and subsequently in a different epitope presentation to IgG antibodies .
We performed analysis of SEREX clones (NY-BR-13, NGO-St-58, and KY-MBC 29-88-1) sequences coding ZRF1 and revealed 159 bp lengths insert in the sequences of clones NGO-St-58 and KY-MBC 29-88-1.
Comparative analysis of ZRF1 SEREX clones showed that they code different protein isoforms of DNAJC2 gene in different tumors and cell lines.
Identification of tumor-associated antigens from medullary breast carcinoma by a modified SEREX approach," Molecular Biotechnology, vol.