The relationship between PLIN2 expression and prognosis, and clinicopathological significance of various cancers has been extensively studied, but the results are not completely consistent. This review followed the guidelines for systematic reviews of prognostic factors studies and was reported under the Preferred Reporting Program for Systematic Reviews and Meta-Analysis (PRISMA). We searched PubMed, Embase, Cochrane Library, Web of Science, and Google Academia for relevant articles up to September 2, 2022, and calculated the pooled hazard ratios (HR) with 95% confidence intervals (CI) to determine the association between PLIN2 expression and the prognosis of various cancers. The meta-analysis ultimately included 17 studies. The quality of all included cohort studies was evaluated using the Quality in Prognosis Studies (QUIPS) tool, and an adaptation of Grading of Recommendations Assessment, Development and Evaluation (GRADE) method was used to assess the certainty of the results. High expression of PLIN2 was associated with poorer overall survival (HR = 1.65; 95% CI = 1.14, 2.38; P = 0.008), metastasis-free survival (HR = 1.48; 95% CI = 1.12, 1.94; P = 0.005), progression-free survival (HR = 2.11; 95% CI = 1.55, 2.87; P < 0.0005) and recurrence-free survival/relapse-free survival (HR = 2.21; 95% CI = 1.64, 2.98; P < 0.0005) in cancers. The clinicopathological parameters of digestive system malignancies suggested that high expression of PLIN2 was notably associated with distant metastasis ( + ) (odds ratio (OR) = 3.37; 95% CI = 1.31, 8.67; P = 0.012), lymph node metastasis ( + ) (OR = 1.61; 95% CI = 1.01, 2.54; P = 0.004), and tumor stage (III-IV) (OR = 1.96; 95% CI = 1.24, 3.09; P = 0.006). In summary, overexpression of PLIN2 is significantly associated with a poor prognosis in various human cancers, especially in respiratory and digestive malignancies. Thus, PLIN2 expression may be a potential prognostic biomarker in cancer patients.
Keywords: PLIN2; cancers; clinicopathologic; meta-analysis; prognosis; systematic review.