"Disease models for basic cancer research rely predominantly on established cell lines and animal studies. Lgr5, an R-spondin receptor, and a specific marker of gastrointestinal tract stem cells, enabled in vitro culture and observation of all steps of their differentiation and self-organization from single cells to “mini-organs”. Organoid cultures are currently the state-of-theart model for studies of colon, esophagus and small intestine pathophysiology. We used this method to produce cancer colonoids from stem cells, isolated from LoVo cell line. LoVo cell line, established from Dukes’ type C, grade IV, colorectal adenocarcinoma, contains, according to the literature, a significant fraction of cancer stem cells (CSCs). CSCs derived from LoVo cell line present distinct growth patterns with varying culture, environment. In 2D, they form a monolayer of spindleshaped cells, in 3D they generate round, spherical structures with smooth edges. As organoids should develop all cell types, present in vivo in human colon, we plan to investigate cell subtypes present in LoVo ‘colonoids’. Also, patterns of demethylation induced changes in gene expression are under evaluation by microarrays."