Clinicopathological significance of altered metallothionein 2A expression in gastric cancer according to Lauren's classification / 中华医学杂志(英文版)

ABSTRACT

<p><b>BACKGROUND</b>Dysregulated metallothionein 2A (MT2A) has been implicated in carcinogenesis. The purpose of this study was to investigate the expression of MT2A in gastric cancer (GC) and its correlation with prognosis.</p><p><b>METHODS</b>Reverse transcription-polymerase chain reaction and real-time polymerase chain reaction were used to detect the mRNA expression of MT2A in 12 GC cell lines, normal gastric epithelial GES-1 cells, and 36 GC and adjacent normal tissues. MT2A protein expression was determined in 258 GC tissues and 171 adjacent normal tissues by immunohistochemistry.</p><p><b>RESULTS</b>MT2A mRNA expression was lower in GC cells and primary tumors than in GES-1 cells and adjacent normal tissues, respectively. High protein expression of MT2A was present in 130 of 171 normal tissues (76.0%) and in 56 of 258 GC tissues (21.7%; P < 0.001). MT2A protein expression was higher in well/moderately differentiated GC (22/54; 40.7%) than in poorly differentiated GC (34/204; 16.7%; P < 0.001). Moreover, the protein expression of MT2A was lower in diffuse-type GC (6/82; 7.3%) than in intestinal-type GC (50/176; 28.4%; P = 0.0001). Importantly, MT2A expression was an independent prognostic factor for GC, and decreased MT2A expression was associated with poor clinical outcome (P < 0.001). The expression status of MT2A could predict prognosis in intestinal and diffuse-type GCs.</p><p><b>CONCLUSION</b>Expression status of MT2A might be a useful prognostic biomarker for GC, especially when used in combination with Lauren's classification.</p>