NDRG1 and breast cancer: NDRG1 protein expression and human epidermal growth factor receptor 2 (Her2) status were found to have a negative relationship (P = 0.01, log OR: -0.76, 95% CI: -1.32–(-0.20), I2: 32.42%, 197 breast cancer cases with Her2 positive and 272 breast cancer cases with Her2 negative, 3 studies).