Expression and significance of LAPTM4B-35 and MMP-9 in patients with gastric cancer / 中国肿瘤临床

ABSTRACT

Objective:To investigate the protein expression level of lysosome-associated transmembrane protein 4β-35 (LAPTM4B-35) and matrix metalloproteinase-9 (MMP-9) in gastric cancer (GC) and to determine the relationship of LAPTM 4B-35 or MMP-9 expres-sion with clinicopathological characteristics and prognosis of patients with GC. Methods:The messenger RNA (mRNA) expression level of LAPTM4B-35 and MMP-9 was detected by real-time quantitative polymerase chain reaction, while the protein expression level of LAPTM 4B-35 and MMP-9 in GC tissues was analyzed by immunohistochemistry in formalin-fixed samples from 152 patients with GC, and data analysis was performed using statistical methods. Results:The mRNA expression level of both LAPTM4B-35 and MMP-9 in HGC-27, SGC 7901, and MGC803 GC cell lines was higher than that in the GES-1 normal gastric mucosa cell line. LAPTM 4B-35 and MMP-9 proteins mainly localized in the cytoplasm of GC cells. The positive LAPTM4B-35 expression ratio in GC tissues was 50.7％, while the MMP-9 positive ratio was 36.8％. LAPTM4B-35 and MMP-9 were positively related to gastric cancer. Lauren's classification and T stage were identified as the relative factors of LAPTM4B-35 expression, while tumor size and N stage were identified as the rela-tive factors of MMP-9 expression in GC tissues. Cox analysis indicated that the degree of differentiation, N stage, LAPTM 4B-35 expres-sion, and MMP-9 expression were independent prognostic indicators for patients with GC. Conclusion:LAPTM4B-35 and MMP-9 play important roles in the aggressiveness of GC, and LAPTM4B-35 and MMP-9 may be promising indicators for the prognosis of patients with GC.