Subsequently, we examined the KCTD12 mRNA expression in normal breast cell HBL100 and breast cancer cell lines MDA‐MB‐231, MCF‐7, BT‐549, SK‐BR‐3, and T47D and found that KCTD12 mRNA levels is significantly decreased in breast cancer cells compared with normal breast cells. This evidence concerns the gene KCTD12 and breast carcinoma.