| The idea of controlling cancer by stimulating the immune system was not a new one. In fact more than a century ago, bacterial extracts were used in order to stimulate tumor-specific immune responses. Contrasted to traditional Adjuvant therapies with radiotherapy or chemotherapy, tumor specific immune response was induced by Immunotherapy to identify and destroy aberrant tumor cells. Use of immunotherpy to prevent and treat breast cancer was a highly attractive approach because of the expected minimal side effects and no toxicity. Immunological memory induced by strong immune response could be used routinely to prevent breast cancer recurrence. So in recent years immunotherapy of tumor was developed quickly. Studies of the interaction of tumor cells with cells of the immune system had led to the development of novel, There was considerable evidence that the immune system can recognize tumor cells by virtue of TAAs. There was a significant effort to design cancer vaccines targeting 'tumor-associated antigens' (TAAs). Breast cancer was the leading cause of cancer-related deaths in women worldwide yearly. A central issue in the management of women with breast cancer was the prevention of metastatic disease. Although primary surgical treatment was generally effective at controlling local disease, many patients had micrometastases at the time of diagnosis. Adjuvant therapies with hormones or chemotherapy had resulted in a modest decrease in the relapse rate, but novel approaches were needed. Immunotherapy attempted to achieve this goal. Many tumor associated antigen (TAAs) of breast cancer had been identified, such as her2/neu?MUC-1?P53?NY-ESO-1?MAGE-1?MAGE-38?SCP-1?CT-7. Breast cancer patients exhibited both circulating antibodies and cytotoxic T lymphocytes (CTLs) that were specific for breast tumor antigens, including HER-2/neu (erbB-2) MAGE-1 [5], and MUC-1. The low levels of expression of these antigens in breast tumor tissue had restrictedthe vaccines based on these antigens used in a limited scope of patients. So potential new targets were being studied that may have relevance to breast cancer immunotherapy.Jager D and his colleagues had applied SEREX (serological analysis of recombinant tumor cDNA expression libraries) to analyse a breast cancer library with autologous patient serum and lead to the isolation differentiation antigen NY-BR-1. In this regard, NY-BR-1 was of considerable interest because of its highly restricted expression pattern in normal tissue, i.e., breast and testis. NY-BR-1 is composed of 37 exons and localized to chromosome 10p11-p12. The production of antibody probes for NY-BR-1 is essential to confirm breast specificity at the protein and cell levels. With regard to cancer vaccine development, the restricted expression of NY-BR-1 in normal breast and breast cancer makes it a highly attractive vaccine target. So at first RT-PCR was used to identify the expression rate of NY-BR-1 in 34 breast cancer samples and 3 breast cancer cell lines. NY-BR-1 was found in 26 breast cancer samples and 2 breast cancer cell lines. So further studies for the immunogenicity of NY-BR-1 would be performed.Applying the combination of methods of polynomial motif prediction and quantitifying motifs to predict the candidate epitopes of NY-BR-1, three HLA-A2-restricted CTL epitopes with highest scores were selected to study. They were MLLQQNVDV(167～175)(307.98)?YLLHENCML(1043～1051)(100.32)?NMWLQQQLV(1274～1282)(358.11). In computer simulation these three candidate peptides were proved to bind HLA-A2 with a distance between the two major anchor residues from 15? and 20?. Non-bond energy and hydrogen bond number of these candidate peptides were in accordance with the requirements for HLA-A2-restricted CTL epitope. Candidate peptides were synthesized with solid phase strategies and purified with reverse-phase HPLC and identified with mass spectrometry.The binding ability of predicted peptides to HLA-A*0201 molecules was determined semi-quantitatively with the T2 binding assay. The results were e...
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