Clinical Significance of Melanoma Antigen-Encoding Gene-1 (MAGE-1) Expression and its Correlation with Poor Prognosis in Differentiated Advanced Gastric Cancer

Abstract

These findings suggest that MAGE-1 protein expression can serve as a predictive marker of poor prognosis in differentiated AGC patients.

Cancer–Testis Antigen Expression in Digestive Tract Carcinomas: Frequent Expression in Esophageal Squamous Cell Carcinoma and Its Precursor Lesions

“…Although the expression of cancer-testis antigens in digestive tract malignancies has been studied at the RNA and protein levels, studies evaluating protein expression are mostly limited to MAGEA, NY-ESO-1, and GAGE (25,(27)(28)(29)(30) (27) MAGEA protein expression in two previous studies, similar to our finding of 58% in this study. This finding of more frequent cancer-testis mRNA expression than protein expression has also been observed in other types of cancer (4) and suggests that lowlevel cancer-testis mRNA expression may not translate to biologically significant protein expression.…”

“…On the other hand, it is difficult to compare these two studies, as Ogata and colleagues (30) only interpreted cases with cytoplasmic staining as MAGEA1-positive based on the debatable notion that MAGEA1 is a cytoplasmic protein (34), whereas Suzuki and colleagues (30) included both positive cytoplasmic and nuclear staining as MAGEA1-positive, which was the more commonly accepted criterion. [Of note, the 6C1 anti-MAGEA antibody that was used in these studies, including ours, in fact detects multiple MAGEA antigens, including MAGEA1, A2, A3, A4, A6, A10, and A12 proteins (31), and to interpret 6C1-positivity, either cytoplasmic and/or nuclear, as MAGEA1 expression (29,30) is in fact misleading.] In our series, we found MAGEA expression in 14% (7 of 50) gastric cancer among all stages, indicating that the true frequency of MAGEA in gastric cancer is likely in the 10% to 15% range.…”

“…Given the heterogeneity of cancer-testis antigen expression in cancer, often expressed in a small percentage of tumor cells, it would be worthy to investigate whether the extent of MAGE protein expression in the tumor would also be another factor that might predict the likelihood of tumor response to MAGEA3 vaccine. In gastric cancer, Ogata and colleagues (29) reported MAGEA1 protein expression in 32.6% (44 of 135) of advanced gastric cancer, whereas Suzuki and colleagues (30) reported expression in only 9.8% (4 of 41) of gastric cancer of all stages. It is possible that at least part of this difference may indicate more frequent expression of MAGEA in late-stage gastric cancer, as 2 of 6 (33%) of T4 cancer in the series from Suzuki and colleagues were MAGEA1-positive compared with only 1 of 14 (7%) of the T1/2/3 tumors.…”

“…Several studies have examined the expression of CT-X antigens in carcinomas of the digestive tract, either at the mRNA level by RT-PCR (23)(24)(25)(26) or, more recently, at the protein level by immunohistochemical (IHC) analysis (25,(27)(28)(29)(30). The latter is clearly more relevant clinically, either as a diagnostic marker or in predicting patients that might benefit from cancertestis antigen-based cancer vaccines, as posttranscriptional control of gene expression can lead to substantial discordance between mRNA and protein expression in cancer cells.…”

Association of MAGE A1-6 Expression with Lung Cancer Progression

“…However, only a few studies reported the correlation between MAGE gene expression and oncologic outcomes. Ogata et al suggested that MAGE A1 expression can be a predictive maker of poor prognosis in differentiated advanced gastric cancer 21. Gu et al demonstrated that MAGE A9 expression suggests unfavorable survival outcome in hepatocellular carcinoma 22.…”