Decreased expression of PC5/6 in intestinal tumors versus adjacent normal tissues. (A) RNA samples from human colonic adenocarcinomas (stage I, II, III or IV) and their adjacent normal tissues were submitted to QPCR analysis (n = 6, 7, 7 and 2 for stages I, II, III and IV, respectively). (B) In each small intestine section (duodenum, jejunum and ileum) from 3 ApcMin/+mice, 2 tumors and their adjacent normal tissue (6 couples/section) were dissected and assessed for the expression levels of furin, PC5/6, PACE4 and PC7 by QPCR. Normalized expression values are shown for the 18 samples of normal tissues and 18 samples of tumors. (C) Expression of PC5/6 and furin in tumors was also analyzed by intestinal section. All mRNA levels in tumors were normalized to their respective normal tissue expression and have been log2 transformed, with the median of the total 18 samples set to 0. *, P < 0.05; **, P < 0.005; ***, P < 5.10-11 (Student's t test).