S100A8 and S100A9 are highly expressed in human colorectal carcinoma.

<p>(A) Immunohistochemistry for S100A8 in representative samples of tumor tissue and matching distal normal tissue from the same patient (moderate differentiation and Dukes' B): black arrow, normal glandular epithelial cells; green arrow, S100A8-expressing tumor cells (brown). High-magnification images of the red boxed areas are shown in the middle and right. Black scale bars = 500 µm; red scale bars = 200 µm; blue scale bars = 100 µm. (B) Immunocytochemical staining of S100A9 in representative samples of tumor tissue and matching distal normal tissue from the same patient (well differentiation and Dukes' A): black arrow, normal glandular epithelial cells; blue arrow, S100A9-expressing tumor cells (brown). High-magnification images of the red boxed areas are shown in the middle and right. Black scale bars = 500 µm; red scale bars = 200 µm; blue scale bars = 100 µm. (C) Western blot analyses for the expression of S100A8 and S100A9 in colorectal carcinoma and matched distal normal tissues from five randomly selected patients' samples. Sample 1, moderate differentiation and Dukes' A; Sample 2, moderate differentiation and Dukes' A; Sample 3, poor differentiation and Dukes' C; Sample 4, moderate differentiation and Dukes' C; Sample 5, poor differentiation and Dukes' D. T, tumors; N, matching distal normal tissues. β-actin were used as an internal reference control. (D) The transcription levels of S100A8 and S100A9 were analyzed using RT-PCR in four random colorectal carcinoma patients. Sample 1, poor differentiation and Dukes' D; Sample 2, moderate differentiation and Dukes' B; Sample 3, moderate differentiation and Dukes' C; Sample 4, moderate differentiation and Dukes' B. T, tumors; N, matching distal normal tissues. GAPDH was used as an internal reference control.