Also, the function of genes implicated in hepatocyte polarity, e.g., Par1b, Pard3, Cldn2, Cldn3, and Lkb1 (cAMP-Epac-MEK-AMPK pathway regulating BC network formation) should be revisited specifically in the context of the bulkheads and anisotropy of lumen elongation (Wang et al., 2014; Fu et al., 2010; Son et al., 2009; Grosse et al., 2013; Slim et al., 2013; Homolya et al., 2014; Fu et al., 2011; Woods et al., 2011). This evidence concerns the gene MARK2 and breast cancer.