• Journal of Life Science
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• v.21 no.6
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• pp.912-922
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• 2011

Cancer-testis (CT) antigens are immunogenic protein antigens with restricted expression in the testes and a wide range of human tumor types, eliciting both humoral and cellular immune responses in cancer patients. They are considered to be ideal targets for vaccine-based immunotherapy, and more than 100 CT antigens, including MAGE, NY-ESO-1, GAGE, BAGE, LAGE, SSX2 and NY-SAR-35 have been identified to date. The CT antigens were identified through various techniques and can be divided in those that are encoded on the X chromosome, the CT-X genes, and those that are not, the non-X-CT genes. CT genes are aberrantly activated and expressed in a proportion of various types of human cancers. The biological role of CT-X in both germ line tissues and tumors remains poorly understood. Cancer vaccine trials based on several CT antigens are currently ongoing. This paper reviews recent advances in and future trends of CT antigens for cancer immunotherapy.

• Journal of Life Science
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• v.19 no.7
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• pp.886-891
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• 2009

Cancer/testis (CT) antigens are immunogenic in cancer patients, exhibit highly tissue-restricted expression, and are considered promising target molecules for cancer vaccines. We investigated the expression of 13 CT genes in 29 Korean patients with primary breast carcinoma. The most frequently expressed CT genes were MAGE-3 (66%) and MAGE-1 (57%), followed by LAGE-1 (55%), NY-SAR-35 (49%), MAGE-4 (41%), NY-ESO-1 (38%), CT-7 (24%) and SSX-4 (24%), whereas SSX-1, SSX-2, MAGE-10 and NY-TLU-57 were found to be expressed significantly less often (3-7%) and SCP-l not all. Expression of at least one antigen was observed in 28 breast cancer samples. Immunohistochemistry was performed for NY-ESO-l and MAGE-3 protein expression in breast tumor samples. NY-ESO-l and MAGE-3 proteins were expressed in 11 of 29 (38%) and 12 of 29 (41 %) breast tumors. Our results suggest that CT antigens may be potential candidates for polyvalent immunotherapy in Korean breast cancer patients.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7703-7705
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• 2014

Cancer-testis (CT) antigens are a group of tumor-associated antigens with restricted expression in normal tissues except for testis and expression in a wide variety of tumor tissues. This pattern of expression makes them suitable targets for immunotherapy as well as potential biomarkers for early detection of cancer. However, some genes attributed to this family are now known to be expressed in other normal tissues which put their potential applications in immunotherapy and cancer detection under question. Here we analyzed expression of two previously known CT antigens, RHOXF2 and PIWIL2, in AML patients versus normal donors and found no significant difference in the expression of these genes between the two groups. As these two genes showed expression in normal leukocytes, their expression pattern seems to be wider than to be attributed to the CT gene family. Future research should focus on the expression profiles of so called CT antigens to find those with more testis specific expression.

• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1082-1089
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• 2007

Serological anlysis of recombinant cDNA expression libraries (SEREX) has led to identification of several categories of new antigens recognized by the immune system of cancer patients, which are referred to as the cancer immunome. We analyzed normal testis cDNA expression libraries with serumobtained from non-small lung cancer patient and isolated 40 distinct antigen designated KP-LuT-1 through KP-LuT-40. Among these antigens 20 antigens were previously identified by SEREX analysis of other tumor types, and 20 out of 40 antigens (50%) did not match entries in Cancer Immunome Database and were considered newly identified antigens. Sequencing analysis showed that the anti-gens comprised 26 functional known proteins and 14 noble/uncharacterized gene products. Of these, the hypothetical protein KP-LuT-6 was shown tissue-restricted. RT-PCR showed it to be expressed strongly only in normal testis. In addition to normal tissues-restricted expression, KP-LuT-6 mRNA was detected in lung tumor samples(3/l0), stomach tumor samples(3/l0), and breast tumor samples(l/5), whereas not detected in colon tumor samples(O/I2). These data suggest that KP-LuT-6 is a cancer/testis (CT)-like antigen as a potential target for cancer immunotherapies.

• BMB Reports
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• v.43 no.6
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• pp.400-406
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• 2010

Cancer/testis (CT) antigens exhibit highly tissue-restricted expression and are considered promising targets for cancer vaccines. Here we identified a novel CT gene ZNF645 which restrictively expresses in normal human testes and lung cancer patients (68.3%). To investigate the promoter methylation status of ZNF645, we carried out bisulfite genomic sequencing and found that the CpG island in its promoter was heavily methylated in normal lung tissues without the expression of ZNF645, whereas there was high demethylation in normal human testes and lung carcinoma tissues with its expression. Also ZNF645 could be remarkably activated in A549 and HEK293T cells treated by DNA demethylation agent 5'-aza-2'-deoxycytidine. And the dual luciferase assay revealed that the promoter activity of the ZNF645 was inhibited by methylation of the CpG island region. Therefore, we proposed that ZNF645 is a CT gene and activated in human testis and lung cancers by demethylation of its promoter region.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.841-846
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• 2007

The identification of tumor antigens is essential for the development of anticancer therapeutic vaccines and clinical diagnosis of cancer. SEREX (serological analysis of recombinant cDNA expression library)has been used to identify such tumor antigens by screening sera of cancer patients with cDNA ex-pression libraries. SEREX-defined antigens provide markers for the diagnosis of cancers. SEREX is also a powerful method for the development of anticancer therapeutics. The development of anticancer vaccines requires that tumor antigens can elicit antigen-specific antibodies or T lymphocytes. This re-view provides information on the application of SEREX for discovery of tumor antigens.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8461-8465
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• 2016

Gastric cancer (GC) as the fourth most common cause of malignancies shows high rate of morbidity appropriating the second leading cause of cancer-related death worldwide. Developmental pluripotency associated-2 (DPPA2), cancer-testis antigen (CT100), is commonly expressed only in the human germ line and pluripotent embryonic cells but it is also present in a significant subset of malignant tumors. To investigate whether or not DPPA2 expression is recalled in GC, our aim in this study was to elucidate DPPA2 protein expression in gastric cancer. Fifty five GC tumor and their related margin normal tissues were recruited to evaluate DPPA2 protein expression and its probable associations with different clinicopathological features of the patients. DPPA2 was overexpressed in GC cases compared with normal tissues (P < .005). While DPPA2 expression was detected in all GC samples, its high expression was found in 23 of 55 tumor tissues (41.8%). Interestingly, 50 of 55 normal samples (90.9%) were negative for DPPA2 protein expression and remained 5 samples showed very low expression of DPPA2. DPPA2 protein expression in GC was significantly correlated with lymph node metastasis (p = 0.012). The clinical relevance of DPPA2 in GC illustrated that high level expression of this protein was associated with lymph node metastasis supporting this hypothesis that alteration in DPPA2 was associated with aggressiveness of gastric cancer and may be an early event in progression of the disease. DPPA2 may be introduced as a new marker for invasive and metastatic GCs.