Among the 18 vital lncRNAs, 9 lncRNAs (LIPE.AS1, AC061992.1, TFAP2A.AS1, LINC00667, AL512625.2, PDCD4.AS1, AC002398.1, AL451085 2, and AC110619.1) were protective factors for the prognosis of breast cancer, while other lncRNAs (LINC02169, LINC01235, LINC01614, AC109826.1, ST8SIA6.AS1, AP003119.3, MIR4435.2HG, AC147067.2, and AC098484.1) behaved the opposite (Supplementary Table 2). This evidence concerns the gene PDCD4 and breast cancer.