CD11b/CD86 involved in the microenvironment of colorectal cancer by promoting Wnt signaling activation.

Background: Colorectal cancer (CRC) is a malignancy that arises within the gastrointestinal tract. Despite ongoing research, the etiology and pathogenesis of CRC remain elusive; particularly, the distribution and characteristics of tumor‐associated macrophages is currently an active area of investigation in understanding the pathological progression and prevention of CRC. Methods: This study utilized CRC patient surgical samples, mouse models of colitis‐associated cancer, colonic organoid, and co‐culture cell line to examine the changes in CD11b/CD86 at different pathological region and detect the Wnt signaling pathway activity. Results: Our findings revealed a sensitive and increased expression of CD11b from the early to the advanced CRC tissues and correlated with poor prognosis, while CD86 expression was reduced in advanced CRC tissues. CD133 expression was also elevated in advanced CRC tissues and mainly co‐localized with CD11b, suggesting a positive regulatory effect of CD11b and CD133 expression that may contribute to CRC progression. In AOM/DSS mouse models, activation of the Wnt signaling pathway was associated with increased CD133 and CD11b expression. In vitro, THP‐1 cell was induced to high expression of CD11b, and the above conditional cultural medium enhanced HCT116 cell colony number and CD133 protein expression. Furthermore, colonic crypts from AOM/DSS mouse models were isolated to culture, and the colonic organoids exhibited dilation and significant increases expression of CD133 and β‐Catenin/N‐P‐B‐Catenin. Conclusions: CD11b might be an important factor to participate the progress of CRC. And the high CD11b of CRC microenviroment might potentially promote CD133 expression and associate with Wnt signal activation. [ABSTRACT FROM AUTHOR]