OBJECTIVETo study the expression of tumorigenesis-related stem cell markers Lgr5 and CD44 in different pathological types of intestinal polyps and their clinical significance in predicting tumorigenesis.

METHODSA total of 145 cases of colorectal polyps, adenomas and cancer tissues were obtained by colonoscopy biopsy. Immunohistochemistry was employed to detect the expression of Lgr5 and CD44 to analyze their relationship with the occurrence and prognosis of colon and rectal cancer.

RESULTSThe expression of CD44 in colon cancer tissue was 95.65%, significantly higher than that in normal mucosa (5%), inflammatory hyperplastic polyps (22.58%), tubular adenomatous polyps (55.26%) and villous polyps (75.76%) (P<0.05). The expression of Lgr5 in colorectal cancer was up to 95.65% while negative in normal colorectal tissue and was 16.12% in inflammatory hyperplastic tissues (P<0.05). The expression rate of Lgr5 was 86.84% in tubular adenoma and 93.94% in villous polyps, both comparable with that in colon cancer (P>0.05). Correlation analysis indicated that the expression of CD44 and Lgr5 were positively correlated with the progression of intestinal polyp tumorigenesis (rs=0.69377, P<0.0001; rs=0.81637, P<0.0001).

CONCLUSIONLgr5 and CD44 are highly expressed in colorectal cancer tissues in close correlation with the clinical and pathological features. The expression profiles of Lgr5 and CD44 represent a distinct feature to differentiate colorectal cancer from normal intestinal mucosa. Lgr5 is more closely correlated with tumor progression of polyps than CD44. This means detecting of the expression of Lgr 5 together with CD44 is important and necessary in clinical diagnosis of patients with early stage colorectal diseases such as polyps and their canceration.