HOXB4 and lung adenocarcinoma: To explore whether miR-10a can suppress hoxd4 expression, the expression levels of the hoxd4 and hoxb4 mRNAs were compared to those of miR-10a and -10b in several human cell lines including human breast cancer cells MDA-MB-231 and MCF7, human mammary epithelial cells (MCF10A), hepatocellular liver carcinoma cells (HepG2), cervical carcinoma cells (HeLa) and lung adenocarcinoma cells (A549) (Fig. 1c, d).