The Expression And Clinicopathological Significance Of CD44~+/SOX2~+ Cells In Colorectal Cancer

PurposeTo observe the expression of CD44 and SOX2 in human colorectal cancer tissues,human colon cancer cell line SW620,and to analyze the biological characteristics of CD44~+,SOX2~+,CD44~+/SOX2~+ cells,to explore the clinic pathological significance of CD44~+,SOX2~+,CD44~+/SOX2~+ cells.Moreover,to investigate whether CD44~+/ SOX2~+ can be used as colorectal cancer stem cell markers in targeted therapy for colorectal cancer.MethodsImmune histochemical staining and immune histochemical double staining were used to investigate the positive intensity and positive rate of CD44 and SOX2 in human colorectal cancer tissues and human colon cancer cell lines and to observe the number and distribution of CD44~+/SOX2~+ cells.HE staining method was used to observe the morphological characteristics of CD44~+/SOX2~+ cells.IBM SPSS Stastitics 22 was used to analyze the relationship between the expression of CD44~+,SOX2~+,CD44~+/SOX2~+ cells in human colorectal cancer tissues and clinicopathological parameters,and P <0.05 was statistically significant.Results1.CD44 was lowly expressed in normal colorectal mucosa but highly expressed in colorectal adenoma and carcinoma tissues,the rate was 20%(2/10),85%(17/20)and 76.14%(67/88)respectively;SOX2 was almost not expressed in normal colorectal mucosa and adenoma tissue,but in colorectal cancer tissue the expression rate went up to 21.59%(19/88).The expression of CD44 and SOX2 in different colorectal tissues was statistically significant(P <0.05).2.There was no correlation between the expression of CD44 and the age of colorectal cancer patients(?~2=2.613,P=0.271),the gender(?~2=5.832,P=0.054),the location(?~2=3.035,P=0.219)and the depth of invasion(r=0.059,P=0.584).There was a negative correlation between the expression of CD44 and the degree of differentiation(r=0.265,P=0.013).There was a positive correlation between the expression of CD44 and TNM stage(r=0.298,P=0.005)and the metastasis(r=0.222,P=0.038).The difference was statistically significant(P <0.05).3.The expression of SOX2 was not related to the age of colorectal cancer patients(?~2=0.167,P=0.920),the gender(?~2=1.347,P=0.510),the location(?~2=0.044,P=0.978),the degree of differentiation(r=0.250,P=0.055)and the depth of invasion(r=0.195,P=0.068).There was a positive correlation between the expression of SOX2 and the TNM stage(r=0.250,P=0.019),and the metastasis(r=0.226,P=0.034).The difference was statistically significant(P <0.05).4.CD44~+/SOX2~+ was almost not expressed in normal colorectal mucosa,while in colorectal adenoma and carcinoma tissues the expression rates were 15%(3/20)and 26.14%(23/88),the difference was statistically significant(r=0.190,P=0.039).The ratio of CD44~+/SOX2~+ cells in colorectal cancer tissues was about 2.57%.There was no correlation between the expression of CD44~+/SOX2~+ and the age of colorectal cancer patients(?~2=1.164,P=0.559),the gender(?~2=1.511,P=0.470),the location(?~2=2.137,P=0.344)and the depth of invasion(r=0.131,P=0.225)respectively.There was a negative correlation between the expression of CD44~+/ SOX2~+ and the degree of differentiation(r=0.221,P=0.039).There was a positive correlation between the expression of CD44~+/SOX2~+ and the TNM stage(r=0.271,P=0.011),and the metastasis(r=0.256,P=0.016),the difference was statistically significant(P<0.05).In HE staining,CD44~+/ SOX2~+ cells were small and have round,oval-shaped structure,with less cytoplasm,large nuclear,obvious nucleolus,rare mitotic.5.The ratio of SOX2~+ cells and CD44~+/SOX2~+ cells in human colon cancer cell line SW620 were about 38.73% and 5.24% respectively.In the HE staining,SW620 cells consisted of polygonal,spindle shaped cells and round,oval cells and other components;CD44~+/SOX2~+ cells were small and mainly seen in the round,oval cells,a few seen in the spindle shaped cells,with less cytoplasm and large nuclear.Conclusion1.CD44 and SOX2 are involved in the occurrence and development of colorectal cancer.2.The expression of CD44~+/SOX2~+ is closely related to the clinicopathological parameters such as the degree of differentiation,the TNM stage and the metastasis,and provide the reference for the prognosis of colorectal cancer.3.CD44~+/SOX2~+ may be a marker of tumor stem cells to provide new therapeutic targets for colorectal cancer.