ESR1 and cancer: However, the mRNA levels of S100A8 and S100A9 are significantly higher in ER--cancer tissues than in their corresponding tumor-adjacent tissues; and (d) only EIF2AK2 mRNA levels were significantly higher in both ER+- and ER--tumor tissues than in their corresponding tumor-adjacent tissues whereas only the mRNA levels of ANXA1were significantly lower in both ER+- and ER--breast tumor tissues than their corresponding tumor-adjacent tissues.