Volume 127, Issue 4, Pages 1030-1037 (October 2004) Suppression of Peutz—Jeghers polyposis by inhibition of cyclooxygenase-2  Lina Udd, Pekka Katajisto, Derrick J. Rossi, Anna Lepistö, Anna—Maria Lahesmaa, Antti Ylikorkala, Heikki J. Järvinen, Ari P. Ristimäki, Tomi P. Mäkelä  Gastroenterology  Volume 127, Issue 4, Pages 1030-1037 (October 2004) DOI: 10.1053/j.gastro.2004.07.059 Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 1 Significance of COX-2 expression for polyposis in Lkb1+/− mice. (A) Western blotting analysis of COX-2 from lysates of unaffected stomach or polyps with indicated diameters from Lkb1+/− mice. Actin levels from the same blot are shown below. (B) Total polyp burden in 8.5-month Lkb1+/− mice wild-type (+/+; n = 11), heterozygote (+/−; n = 11), or null (−/−; n = 9) in regard to Cox-2. The mean polyp burden of Lkb1+/− mice wild-type for Cox-2 (284 ± 106 mm3; mean indicated by horizontal line) is significantly (P < 0.05) reduced both in Cox-2+/− (133 ± 55.0 mm3) and in Cox-2−/− (132 mm3 ± 83.5 mm3) mice. Gastroenterology 2004 127, 1030-1037DOI: (10.1053/j.gastro.2004.07.059) Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 2 Celecoxib treatment reduces polyp burden in Lkb1+/− mice. (A) Comparison of polyp size distribution between celecoxib-treated and control mice shown as a treated/control ratio for the indicated size categories (diameter in mm). No polyps of the largest size category (>5 mm) were found in treated mice, compared with 5 in the controls. (B) Total polyp burden in 10-month Lkb1+/− control mice (n = 17; 881 ± 585 mm3; mean indicated by horizontal line) or mice treated between 3.5 and 10 months with celecoxib (n = 17; 127 ± 60.2 mm3), demonstrating a highly significant decrease (P < 0.001). Gastroenterology 2004 127, 1030-1037DOI: (10.1053/j.gastro.2004.07.059) Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 3 Celecoxib treatment reduces the microvessel density (MVD) of Lkb1+/− polyps. (A) Analysis of histology (Herovici’s stain) from polyps of control and 3.5–10-month celecoxib-treated Lkb1+/− mice. (B) Apoptosis assay (TUNEL) of polyps of Lkb1+/− mice from the same experiment. Examples of apoptotic nuclei are shown in the higher magnification inserts. (C) Anti-CD31 immunostaining of polyp sections from control and 3.5–10-month celecoxib-treated Lkb1 +/− mice (Original magnification ×400); bar represents 50 μm. (D) Mean microvessel density from control and celecoxib-treated mice determined from the CD31 immunostainings (see Materials and Methods section). The mean MVD is significantly (P < 0.01) reduced from 23.9 ± 4.8 (control; n = 21) to 11.0 ± 2.61 (celecoxib; n = 6) vessels/400× microscope field. Gastroenterology 2004 127, 1030-1037DOI: (10.1053/j.gastro.2004.07.059) Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 4 Reduction of polyp burden following celecoxib treatment in a subset of PJS patients. (A) Herovici staining of a gastric Peutz–Jeghers polyp from patient P6. (B) Herovici staining of a small gastric polyp with hyperplasia, branching and irregular foveolae, and a slight increase in smooth-muscle cells. (C and D) Still images from gastroscopic video recordings with a view toward the anthrum of the stomach of patient P6 before and after the 6-month celecoxib treatment as indicated. A medium-sized polyp (<0.5 cm; asterisk) and 2 small polyps (arrowheads) are marked. (E) The change in polyposis grade of indicated patients (P1-P6) before and after celecoxib treatment, in which positive values indicate reduction in polyp burden (see Materials and Methods section). Error bars indicate the confidence intervals of the mean gradings of 5 evaluators. Asterisks mark significant (*P < 0.05) and highly significant (***P < 0.001) changes in polyposis grade. Gastroenterology 2004 127, 1030-1037DOI: (10.1053/j.gastro.2004.07.059) Copyright © 2004 American Gastroenterological Association Terms and Conditions