PTPRD and ovarian cancer: After further screening by LASSO and multivariate cox stepwise regression analysis, 13 lncRNAs were included in the final signature construction, including four ovarian cancer prognostic risk lncRNAs (MIR223HG, KRT7-AS, PTPRD-AS1 and LINC01094), and 9 prognostic protection lncRNAs (MYCNOS, AL161772.1, USP30-AS1, ZNF32-AS2, AC068733.3, AC012236.1, AC015802.5, KIAA1671-AS1 and AC013403.2).