CD274 and breast cancer: Although, PD-L1 expression (18), high tumor mutation load (19), HER2 (20), and interleukin (IL)-6 (21) were successful illustrations of tumor and BC immune biomarkers, their technical detection problems (22) and instability in extended cryopreservation blood samples (23) have urged the discovery of novel stable immune biomarkers, the long non-coding (lnc)RNAs.