PIK3CA and breast carcinoma: In vitro and whole genome studies have shown that HOX antisense intergenic RNA (HOTAIR) recruits PRC2 and LSD1 complexes to the promoter regions of target genes in breast cancer, resulting in changed expression of over 850 genes in TGF-β, JAK/STAT, PI3K/AKT and PTEN pathways and increased invasion and metastasis of breast cancer cells3.