Identification of a new cancer/testis antigen from small cell lung cancer

Abstract

21182 Background: Serological analysis of recombinant cDNA expression libraires has led to identification of tumor antigens, which are considered promising candidates for early detection and immunotherapy. They are recognized by the immune system of cancer patients including small cell lung cancer (SCLC) patients. Methods: SEREX method was used to screen normal testis and NCI-H889 cell line cDNA library with serum obtained from a SCLC patient who has survived over 50 months. Also SADA test was done to SCLC patients and normal serum. Results: Immunoscreening of libraries with the selected serum led to the isolation of 58 (SCLC-1 through SCLC-58) and 18 (SCLCT-1 and SCLCT-18) independent antigens from NCI-H889 and testis respectively. Of these SCLCT-1 mRNA was expressed strongly only in normal testis. According to the SADA test, SCLCT-1 was only found in SCLC patients’ sera (34%). Conclusions: On the basis of its immunogenecity in SCLC patients’ sera, and its restricted mRNA expression profile, SCLCT-1 can be considered a novel CT antigen. No significant financial relationships to disclose.