PCSK9 and breast carcinoma: Subsequent univariate Cox regression and LASSO regression analyses in breast cancer samples of TCGA screened out 11 genes including VAT1L, TMEM92, SDC1, RORB, PCSK9, NRN1, NACAD, JPH3, GJA1, BMP8B and ADAMTS2 as the candidate genes for prognostic model construction.