Lack of relationship between PROX1 expression and clinicopathological parameters and prognosis in gastric cancer patients: a meta-analysis and TCGA analysis

Background: The relationship between PROX1 expression and clinicopathological characteristics and prognosis in patients with gastric cancer (GC) remain controversial. The aim of this study is to determine the clinicopathological and prognostic significance of PROX1 expression in patients with GC. Methods: A systematic literature search and meta-analysis were performed. Odds ratio (OR) and confidence interval (CI) were used to evaluated the relationship between PROX1 expression and clinicopathological characteristics and overall survival (OS) of GC patients. Additionally, the Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) datasets were utilized to examine the relationship between PROX1 expression and clinicopathological significance and OS in GC patients. Results: A total of 8 studies pooling 1289 GC patients were included in the assessment. In GC patients, PROX1 expression was not related to gender (OR: 1.234, 95% CI 0.958-1.590, P = 0.104), depth of tumor invasion (OR: 0.742, 95% CI 0.428-1.287, P = 0.289), lymph node metastasis (OR: 2.161, 95% CI 0.808-5.779, P = 0.125), TNM stage (OR: 1.324, 95% CI 0.572-3.066, P = 0.513), tumor size (OR: 0.889, 95% CI 0.502-1.576, P = 0.687), distant metastasis (OR: 1.096, 95% CI 0.470-2.555, P = 0.763). In addition, we also found that PROX1 expression was not associated with 1-year OS (OR: 0.908, 95% CI 0.631-1.306, P = 0.602), 3-year OS (OR: 1.234, 95% CI 0.482-3.160, P = 0.661) and 5-year OS (OR: 0.853, 95% CI 0.266-2.736, P = 0.790). According to TCGA, in comparison with high and low PROX1 expression in GC patients, the OS did not differ statistically (p = 0.119). Conclusion: The expression of PROX1 was shown to lack a significant relationship to gender, TNM stage, depth of invasion, tumor size, stage, distant metastasis, or lymph node metastasis in statistically. The expression of PROX1 was not related to OS and it failed to be a meaningful biomarker to prevent and diagnose GC.