Thus, it is possible that this single nucleotide polymorphism (SNP) in the ERAP2 gene has been selected against in order to prevent alteration of the immune privileged uterine environment, and to allow tumors to escape immune recognition.
Importantly, overexpression of ERAP2 was associated with positive N stage, advanced overall stage, positive perineural invasion, and tumor depth (<i>P</i> = 0.041, 0.015, 0.010, and 0.032, respectively).
Altered expression of the ER-resident aminopeptidases ERAP1 and ERAP2 might play an important role in shaping the MHC class I-presented peptide repertoire, but their function in tumors has not been determined in detail.
Thus, low and/or imbalanced expression of ERAP1 and probably ERAP2 may cause improper Ag processing and favor tumor escape from the immune surveillance.