Overexpression of B7-H4 gene in gastric cancer as a potential diagnostic biomarker

Gastric cancer is one of the most common cancers with high mortality. B7-H4 has been identified as potential novel diagnostic biomarker in gastric cancer. But, its clinical significance in this area is still unclear. The purpose of the present study was to examine the expression level of B7-H4 mRNA in tumor tissue of gastric cancer patient with and without history in comparison with their marginal tissue. Also we evaluate its role in tumor progression and prognosis.  

In this study, paraffin blocks were studied from 60 patients with gastric adenocarcinoma (30 with metastasis at the time of diagnosis and 30 without evidence of metastasis) who underwent gastrectomy during 1387-97 in Imam Khomeini Hospital in Tehran. Samples were taken from paraffin blocks by punching method (including tumor and tumor margin for each sample) after the area was identified by the pathologist. RNA extraction was performed from tumor sections and tumor margins. B7-H4 mRNA expression was assessed by quantitative Real-time polymerase chain reaction (qRT-PCR).

Increased expression of B7-H4 mRNA was observed in 81.5% of tumor tissues. There was a significant difference in B7-H4 mRNA expression in tumor tissues of cases with metastasis (p <0.001) and without metastasis (p <0.003) compared to tumor margin. However, comparison of B7-H4 mRNA expression between tumor tissues of metastatic and non-metastatic individuals did not show a significant difference (p = 0.732). Analyzes did not show a significant relationship between B7-H4 mRNA expression and clinical and histopathological variables.

Our findings indicate the possible role of B7-H4 as a potential diagnostic biomarker in patients with gastric cancer. Although more research is needed in this area.