PIK3CA and gastric cancer: We also found that mRNA expression levels of CDH1, CDKN1A, and EP300 were significantly reduced while those of RhoA, ROCK1, ROCK2, PIK3CA, and CCND1 were significantly increased in gastric cancers with reduced or loss of NKX6.3 expression compared to those in NKX6.3 positive cases (Fig. 6C).