To implement a meta-analysis to investigate the relationship between high-mobility group box 1 (
HMGB1) overexpression in the tissue and serum of
ovarian cancer patients, and to evaluate its prognostic significance.
METHODS: Searches were made of China National Knowledge Infrastructure, EMBASE, WanFang, PubMed, MEDLINE, and Web of Science databases up to August 2015, with no language or style restrictions. Reference lists of related studies were also carefully reviewed to identify additional articles.
RESULTS: The literature search identified a total of 12 relevant studies on
HMGB1 expression for inclusion in the meta-analysis: seven in ovarian
tumor tissue, four in ovarian
tumor patient serum, and one in both tissue and serum.
HMGB1 protein levels in
ovarian cancer tissues were notably higher than those in normal ovarian tissues with no evidence of heterogeneity between studies (RD=0.64, 95% confidence interval (CI): 0.57-0.70, Z=18.70, P<0.00001, I (2)=15%), and also higher than those in benign
tumor tissues with no evidence of heterogeneity between studies (RD=0.52, 95% CI: 0.43-0.61, Z=11.14, P<0.00001, I (2)=0). Serum
HMGB1 levels were similarly significantly higher in
ovarian cancer patients than those with benign
tumors or normal ovaries. Pooled mean differences of
HMGB1 in
ovarian cancer patients compared with patients with benign
tumors or normal ovaries were 99.32 with 95% CI: 67.82-130.81, Z=6.18, P<0.00001, and 95.34 with 95% CI: 62.11-128.57, Z=5.62, P<0.0001. The pooled relative risk of
ovarian cancer with high vs low
HMGB1 expression levels was 1.40 with 95% CI: 1.09-1.79, Z=2.66, P=0.008, heterogeneity I (2)=50%.
CONCLUSION: This meta-analysis suggested that
HMGB1 levels in both tissue and serum of
ovarian cancer patients were significantly higher than those of benign
tumor and normal ovarian samples. High serum or tissue
HMGB1 expression may therefore be an effective molecular marker for ovarian benign or malignant
tumor diagnosis and patient prognosis.