Table 1 Summary of the various oncogenic and tumour suppressor roles previously ascribed for LGR5 in CRC

LGR5 is overexpressed in CRC

Primary human/mouse CRC and adenoma cells^{23,24,25,26,27,28,29,30,31,32,33,34,35,36,37}

LGR5 expression predicts adverse prognosis

Primary human CRC;^{7,24,26,27,29} Meta-analyses^41,42

LGR5 knockdown reduces proliferation, growth, migration, clonogenicity, invasion, PGE2-mediated survival and increases apoptosis, chemosensitivity

Human CRC cell lines;^34,46,47,48 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

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 tumours^57,58

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 tumours^57,58