(A and B) Normal colonic mucosa. Note the rare (→) positivity for CD133 (A, × 200 and B, × 400). (C) A early dysplastic lesion of colon tumorigenesis showing a marked positive immunostaining for CD133 (× 200). (D) Example of a moderately differentiated NAS adenocarcinoma displaying a diffuse staining for CD133 (× Obeticholic molecular weight 200). (E and F) Examples of mucinous poorly differentiated

adenocarcinomas displaying a strong and diffuse cytoplasmic staining for CD133 with a clear immuno-negativity of nuclei (× 200 and × 550). In cancer cells the median percentage of positive cells was 5% (range 0–80; mean = 13%) and CD133 staining was not detectable in Daporinad ic50 tumour cells in 30 out of 137 (22%) specimens (Figure 1C-F). When cases were stratified according with pT parameter, median percentage of positive cells was 17.5 (range 0–70; mean = 24%), 10.0 (range 0–60; mean = 16), 2.0 (range 0–65; mean = 9) and 10 (range 0–80; mean = 13) in pT1, 2, 3 and

4 tumours, respectively, and these differences were significant (p = 0.02). MK 1775 Moreover, using the 5% positive cells as cut-off to distinguish between high (>5%) and low (≤5%) staining, high CD133 staining was detected in 9 (75%) of the 12 pT 1 cancers and in 10 (59%), 27 (36%) and 19 (58%) of the pt2, pT3 nd pT4 cancers, respectively and cross-tab analysis identified a significant correlation (p = 0.02) between the two parameters (Table 2). Significance was also evident when earlier (pT1-2) tumours (66%) were compared together vs more advanced (pT3-4) (42.6%) cancers (p = 0.02). Table 2 CD133 expression in relation to clinical and pathological parameters in a series of 137 colon cancers   Total Low High p value     n (%) n (%)   Gender Males 78 41 (53) 37 (47)   Females 59 31 (52) 28 (48) Sinomenine n.s. Age (yr) ≤68 73 35 (48) 38 (52)   >68 64 37 (58) 27 (42) n.s. Tumor Grading 1 9 4 (44)

5 (56)   2 86 50 (58) 36 (42)   3 42 18 (43) 24 (57) n.s. pT parameter pT1 12 3 (25) 9 (75)   pT2 17 7 (41) 10 (59)   pT3 75 48 (64) 27 (36)   pT4 33 14 ( 42) 19 (58) 0.02 Nodal status Negative 76 42 (55) 34 (45)   Positive 61 30 (49) 31 (51) n.s. Tumor stage I 25 9 (36) 16 (64)   II 43 31 (72) 12 (28)   III 69 32 (46) 37 (54) 0.006 Recurrence YES 57 22 (39) 35 (61)   NOT 80 50 (62) 30 (37) 0.005 Follow-up Deceased 51 20 (39) 31 (61)   Alive 86 52 (61) 34 (39) 0.013 α-DG staining Low 68 28 (41) 40 (59)   High 69 44 (64) 25 (36) 0.006 n.s.: not significant. On the other hand, high CD133 staining was detected in 16 (64%) of the 25 stage 1, 12 (28%) of the 43 stage II and in 37 (54%) of the 69 more advanced stage 3 cancers and cross-tab analysis identified a significant correlation (p = 0.006) between the two parameters (Table 2). Significance was no longer evident when stage 1/2 cancers (41%) were compared overall with more advanced stage 3 cancers (54%) (p = 0.09) (Table 2).