Characterization of LGR5 expression in poorly differentiated colorectal carcinoma with mismatch repair protein deficiency

Abstract

Background: Leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5) is a promising intestinal stem cell and carcinoma stem cell marker. We examined the relationship between mismatch repair (MMR) protein deficiency and LGR5 expression in poorly differentiated (PD) colorectal carcinoma (CRC). Methods: In 29 cases of PD-CRC, deficiencies in MMR proteins (MLH1, PMS2, MSH2, MSH6) and β-catenin expression were identified by immunohistochemistry (IHC).LGR5 expression was examined by the RNAscope assay in tissue microarrays. Results:LGR5 H-scores in MMR-deficient (MMR-D) cases were significantly lower than those in MMR-proficient (MMR-P) cases (P = 0.0033). Nuclear β-catenin IHC scores in MMR-D cases were significantly lower than those in MMR-P cases (P = 0.0024). In all cases, there was a positive correlation between LGR5 H-score and nuclear β-catenin IHC score (r = 0.6796, P < 0.001). Even in MMR-D and MMR-P cases, there was a positive correlation between LGR5 H-score and nuclear β-catenin IHC score (r = 0.7180, P < 0.0085 and r = 0.6574, P < 0.003, respectively). MMR-D CRC cases showed low expression of LGR5, which may be due to low activation of the Wnt/β-catenin signaling pathway. Conclusions:Our results reveal the relationship between LGR5 expression and MMR protein profiles in PD-CRC. A further study is warranted to confirm these findings.

Controlling for cellular heterogeneity using single-cell deconvolution of gene expression reveals novel markers of colorectal tumors exhibiting microsatellite instability

“…We first aimed to determine cell type composition differences between MSI-H and MSS/MSI-L CRC tumors. We replicated a number of known findings, including increased CD8 + T cells and macrophages in MSI-H tumors, which are consistent with results of a meta-analysis of MSI-H tumors across several microarray datasets [ 33 ], as well as in MMR deficient CRC tumors [ 34 ]. CD8 + T tumor infiltrating lymphocytes (TIL)s were also seen in greater number in MSI-H tumors [ 35 ].…”

Exploring a new candidate gene, MSH6, related to hepatocellular carcinoma based on bioinformatics

“…The PPI results showed that MSH6 was highly correlated with CXCR6, IDO1, TNFRSF9, FCGR3B, IL13, KLRK1, CXCL10, CD27, CD19, IFNG, FOXP3 and CD8A. Walter Rayford et al showed that IFNG has a negative correlation with MSH6 in prostate cancer 27 . Hee Sang Hwang et al showed that CD8-and FoxP3-positive colorectal and gastric cancers were more strongly correlated with microsatellite instability (MSI) 28 .…”

LGR5 expression is associated with prognosis in poorly differentiated gastric adenocarcinoma

“…Paraffin blocks fixed with 8% formaldehyde containing sufficient tumor for analysis were prepared for hematoxylin and eosin (HE) staining and tissue microarray (TMA) analysis by extracting a core with a diameter of 3 mm from each case. Additionally, the TMA was subjected to immunostaining using antibodies against the following mismatch repair proteins (MMRPs): MLH1 (ES05; mouse monoclonal; dilution 1:50), PMS2 (EP51; rabbit monoclonal; dilution 1:40), MSH2 (FE11; mouse monoclonal; dilution 1:50), or MSH6 (EP49; rabbit monoclonal; dilution 1:50; Agilent Technologies, Santa Clara, CA, USA), as described previously [ 10 ]. Representative images of the slides were captured with an Olympus DP74 camera (lens, × 40; Olympus, Tokyo, Japan) using the CellSens Standard software (Olympus, Tokyo, Japan).…”

“…LGR5 mRNA detection was performed using the RNAscope® kit (Advanced Cell Diagnostics, Hayward, CA, USA), as described previously [ 10 ]. Additionally, a four-step evaluation method we reported previously was used [ 10 ]. Furthermore, LGR5 mRNA expression levels were categorized as low expression (grades 0, 1+, 2+, and 3+) and high expression (4+).…”