Investigation of melanoma-associated antigen A4 cancer/testis antigen clinical relevance in esophageal squamous cell carcinoma.

Abstract

Esophageal squamous cell carcinoma (ESCC) is considered as the seventh most common cancer worldwide, and the second prevalent malignancy in the north of Iran. A subfamily group of tumor-specific antigens, commonly specified as cancer/testis antigens (CTAs), are expressed restrictedly in testis, ovary, and placenta. Melanoma-associated antigen A4 (MAGEA4) as a CTA is overexpressed in a variety of cancers. Expressional analysis of MAGEA4 protein in ESCC may be useful to investigate its clinical relevance leading to effective improvements in ESCC diagnosis and treatment. Fifty-six ESCC patients with no preoperative therapeutic circumstance such as radiotherapy or chemotherapy were analyzed to explore the protein expression level of MAGEA4 using immunohistochemistry assay. MAGEA4 overexpression was detected in 66% of ESCC samples showing strong nuclear and cytoplasmic staining compared to the normal epithelium. There were significant correlations between MAGEA4 protein expression and depth of tumor invasion (P = 0.019), and the number of involved lymph nodes (P = 0.045). Because of the significant correlation of MAGEA4 and indices of poor prognosis, the role of this CTA may be confirmed in ESCC aggressiveness and metastasis. Therefore, MAGEA4 may be a promising therapeutic candidate for suppressing ESCC aggressiveness.