Figure 2. Expression of CHST11, CHST3 and CHST7 in epithelium and stroma.

(A) In the normal and malignant prostate stromal and epithelial tissues obtained by laser capture -microdissection (LCM), mRNA expression of the chondroitin-4-sulfotransferase CHST11 is significantly greater in the stroma, both normal and malignant, than in the epithelium (p < 0.001, n = 6). CHST expression is significantly lower in the malignant epithelium, compared to the normal epithelium (p < 0.001; n = 6). (B) In cultured normal prostate stromal cells, CHST11 expression is significantly more than in epithelial cells (p < 0.001; n = 6). ARSB silencing by siRNA leads to declines in CHST11 expression in both stromal and epithelial cells (p < 0.001; n = 6). (C) In the normal and malignant prostate stromal and epithelial tissues obtained by LCM, the mRNA expression of CHST3, a chondroitin-6-sulfotransferase, is higher in the epithelium than in the stroma, and similar in normal and malignant tissue (p < 0.001, n = 6). CHST7, another chondroitin 6-sulfotransferase, is not significantly different in stroma vs. epithelium or in malignant vs. normal tissue. (D) There are no significant differences in CHST7 expression between the prostate stromal and epithelial cells when ARSB is silenced. (E) The expression of CHST11 is increased in both the normal human prostate epithelial cells (CRL-2850) and in the malignant PC-3 cell line (CRL-1435, ATCC) following exposure to exogenous TGF-β (10 ng/ml × 24 h; p < 0.001, n = 3). This is consistent with previous data about the effect of TGF-β on CHST11 expression and shows that the pathway for expression is intact in the epithelial cells [50]. ^*** represents p ≤ 0.001 and greater than control; ^### represents p ≤ 0.001 and less than control. [ARSB = arylsulfatase B; CHST = chondroitin sulfotransferase; LCM = laser-capture microdissection; PC-3 = metastatic prostate cell line; PEC = prostate epithelial cell; si = siRNA; TGF-β = transforming growth factor β]