Table 1.

Summary of the various oncogenic and tumour suppressor roles previously ascribed for LGR5 in CRC

Main findings	Models and studies
Oncogenic roles for LGR5 in CRC
LGR5 is overexpressed in CRC	Primary human/mouse CRC and adenoma cells23–37
LGR5 expression predicts adverse prognosis	Primary human CRC;7,24,26,27,29 Meta-analyses41,42
LGR5 knockdown reduces proliferation, growth, migration, clonogenicity, invasion, PGE2-mediated survival and increases apoptosis, chemosensitivity	Human CRC cell lines;34,46–48 Human adenoma cell lines50
LGR5 overexpression increases proliferation and chemo-resistance	Human CRC cell lines27
LGR5 positivity confers greater clonogenic capacity	Human CRC cell lines and primary human CRC tumours49
Tumour suppressor roles for LGR5 in CRC
Loss of LGR5 expression during CRC progression	Human CRC cell lines and primary CRC tumours;50,53 Primary human CRC cells52
LGR5 expression predicts favourable prognosis	Primary human CRC52
LGR5 suppresses Wnt signalling	Mouse small intestine;54,55 Human CRC cell lines;56 Human CRC cell lines and primary human CRC tumours57,58
LGR5 knockdown increases invasion, growth, proliferation (including EGF-mediated) and tumourigenicity	Human CRC cell lines;56 Human adenoma cell lines51
LGR5 overexpression reduces proliferation	CRC cell lines;56 Human CRC cell lines and primary human CRC tumours57,58