PIK3CA and non-small cell lung carcinoma: Furthermore, Mansoori et al. discovered that the expression of miR-142-3p is downregulated in ER-positive breast cancers, and that restoring its expression in ER-positive breast cancer cells may reduce and induce cell viability and apoptosis, respectively, in the cells [20].  However, Wang et al. demonstrated that miR-142-5p acts as a growth inhibitory miRNA and has a significant role in preventing the development of non-small cell lung cancer by targeting PIK3CA [21].