The predictive value of PRDM2 in solid tumor: a systematic review and meta-analysis

BACKGROUND: Many studies have reported the presence of Positive Regulatory/Su(var)3-9, Enhancer-of-zeste and Trithorax Domain 2 (PRDM2) downregulation in cancer. However, its potential as a diagnostic biomarker is still unclear. Hence, a systematic review and meta-analysis were conducted to address this issue. INTRODUCTION: As of 2018, cancer has become the second leading cause of death worldwide. Thus, cancer control is exceptionally vital in reducing mortality. One such example is through early diagnosis of cancer using tumor biomarkers. Having a function as a tumor suppressor gene (TSG), PRDM2 has been linked with carcinogenesis in several solid tumor. This study aims to assess the relationship between PRDM2 downregulation and solid tumor, its relationship with clinicopathological data, and its potential as a diagnostic biomarker. This study also aims to evaluate the quality of the studies, data reliability and confidence in cumulative evidence. MATERIALS & METHODS: A protocol of this study is registered at the International Prospective Register of Systematic Reviews (PROSPERO) with the following registration number: CRD42019132156. PRISMA was used as a guideline to conduct this review. A comprehensive electronic search was performed from inception to June 2019 in Pubmed, Cochrane Library, ProQuest, EBSCO and ScienceDirect. Studies were screened and included studies were identified based on the criteria made. Finally, data synthesis and quality assessment were conducted. RESULTS: There is a significant relationship between PRDM2 downregulation with solid tumor (RR 4.29, 95% CI [2.58–7.13], P < 0.00001). The overall sensitivity and specificity of PRDM2 downregulation in solid tumors is 84% (95% CI [39–98%]) and 86% (95% CI [71–94%]), respectively. There is a low risk of bias for the studies used. TSA results suggested the presence of marked imprecision. The overall quality of evidence for this study is very low. DISCUSSION: We present the first meta-analysis that investigated the potential of PRDM2 downregulation as a diagnostic biomarker in solid tumor. In line with previous studies, our results demonstrated that PRDM2 downregulation occurs in solid tumor. A major source of limitation in this study is the small number of studies. CONCLUSIONS: Our review suggested that PRDM2 is downregulated in solid tumor. The relationship between PRDM2 downregulation and clinicopathological data is still inconclusive. Although the sensitivity and specificity of PRDM2 downregulation are imprecise, its high values, in addition to the evidence that suggested PRDM2 downregulation in solid tumor, hinted that it might still have a potential to be used as a diagnostic biomarker. In order to further strengthen these findings, more research regarding PRDM2 in solid tumors are encouraged.