HLA-G and neoplasm: HLA-G loss of expression at the tumor cell-surface during cell culture could be explained by (i) the absence of transcription factors related to the hypoxic microenvironment or (ii) the lack of several cytokines such as IFN-γ, IFN-α, and IL-10 (110), but (iii) could also be related to a HLA-G isoform switch that could not be detected since antibodies detecting all the isoforms of HLA-G are missing, particularly for those that lack the α1 domain (111).