15-hydroxyprostaglandin dehydrogenase in colorectal mucosa as a potential biomarker for predicting colorectal neoplasms

Preventive Anti-inflammatory Diet to Reduce Gastrointestinal Inflammation in Familial Adenomatous Polyposis Patients: A Prospective Pilot Study

Familial adenomatous polyposis (FAP) is an autosomal-dominant hereditary condition associated with germline mutations in the adenomatous polyposis coli gene. Patient management involves prophylactic surgery and intensive life-long endoscopic surveillance. Diet is a major concern for patients with FAP, who are generally free of symptoms before surgery but tend to have issues related to bowel function postoperatively. We hypothesized that a low-inflammatory diet based on the principles and recipes of the Mediterranean diet would reduce markers of local and systemic inflammation. Twenty-eight patients with FAP over 18 years of age who underwent rectum-sparing prophylactic colectomy and were included in our surveillance program participated in a pilot dietary intervention study. Blood and stool samples at baseline (T0), at the end of the dietary intervention (T1, three months), and at the end of the study (T2, six months after T0) were collected. Gastrointestinal inflammation markers including fecal calprotectin, cyclooxygenase-2, and 15-hydroxyprostaglandin dehydrogenase were evaluated. Serum calprotectin, insulin, insulin-like growth factor-1, C-reactive protein, and glycated hemoglobin were also assessed. Significant changes in serum calprotectin, insulin, and insulin-like growth factor-1 levels occurred over time. Borderline significant changes were observed in the neutrophil-lymphocyte ratio. These changes were noticeable immediately at the end of the 3-month active dietary intervention (T1). A significant increase in 15-hydroxyprostaglandin dehydrogenase expression in the normal crypts of matched samples was also observed between T0 and T2. This pilot study supports the hypothesis that a low-inflammatory diet can modulate gastrointestinal markers of inflammation in individuals with FAP. PREVENTION RELEVANCE: Cancer is known to be related to inflammatory conditions. This study suggests that anti-inflammatory dietary intervention may potentially prevent adenomas and cancer in FAP patients by reducing systemic and tissue inflammatory indices.

15-Hydroxyprostaglandin dehydrogenase as a marker in colon carcinogenesis: analysis of the prostaglandin pathway in human colonic tissue

Background/Aims

Cyclooxygenase-2 (COX-2), 15-hydroxyprostaglandin dehydrogenase (15-PGDH), and microsomal prostaglandin E synthase-1 (mPGEs-1) regulate prostaglandin E₂ (PGE₂) expression and are involved in colon carcinogenesis. We investigated the expression of PGE₂ and its regulating genes in sporadic human colon tumors and matched normal tissues.

Methods

Twenty colonic adenomas and 27 colonic adenocarcinomas were evaluated. COX-2 and 15-PGDH expression was quantified by real-time polymerase chain reaction. The expression of PGE₂ and mPGEs-1 was measured using enzyme-linked immunosorbent assay and Western blotting, respectively.

Results

The expression of COX-2, mPGEs-1, and PGE₂ did not differ between the adenomas and matched distant normal tissues. 15-PGDH expression was lower in adenomas than in the matched normal colonic tissues (P<0.001). In adenocarcinomas, mPGEs-1 and PGE₂ expression was significantly higher (P<0.001 and P=0.020, respectively), and COX-2 expression did not differ from that in normal tissues (P=0.207). 15-PGDH expression was significantly lower in the normal colonic mucosa from adenocarcinoma patients than in the normal mucosa from adenoma patients (P=0.018).

Conclusions

Early inactivation of 15-PGDH, followed by activation of COX-2 and mPGEs-1, contributes to PGE₂ production, leading to colon carcinogenesis. 15-PGDH might be a novel candidate marker for early detection of field defects in colon carcinogenesis.

Expression of PGDH correlates with cell growth in both esophageal squamous cell carcinoma and adenocarcinoma

Esophageal cancer represents the fourth most common gastrointestinal cancer and generally confers a poor prognosis. Prostaglandin-producing cyclo-oxygenase has been implicated in the pathogenesis of esophageal cancer growth. Here we report that prostaglandin dehydrogenase, the major enzyme responsible for prostaglandin degradation, is significantly reduced in expression in esophageal cancer in comparison to normal esophageal tissue. Reconstitution of PGDH expression in esophageal cancer cells suppresses cancer cell growth, at least in part through preventing cell proliferation and promoting cell apoptosis. The tumor suppressive role of PGDH applies equally to both squamous cell carcinoma and adenocarcinoma, which enriches our understanding of the pathogenesis of esophageal cancer and may provide an important therapeutic target.

Aspirin and the risk of colorectal cancer in relation to the expression of 15-hydroxyprostaglandin dehydrogenase (HPGD)

Aspirin use reduces the risk of colorectal neoplasia, at least in part, through inhibition of prostaglandin-endoperoxide synthase 2 (PTGS2, cyclooxygenase 2)-related pathways. Hydroxyprostaglandin dehydrogenase 15-(nicotinamide adenine dinucleotide) (15-PGDH, HPGD) is down-regulated in colorectal cancers and functions as a metabolic antagonist of PTGS2. We hypothesized that the effect of aspirin may be antagonized by low 15-PGDH expression in the normal colon. In the Nurses' Health Study and the Health Professionals Follow-Up Study, we collected data on aspirin use every 2 years and followed up participants for diagnoses of colorectal cancer. Duplication-method Cox proportional, multivariable-adjusted, cause-specific hazards regression for competing risks data was used to compute hazard ratios (HRs) for incident colorectal cancer according to 15-PGDH mRNA expression level measured in normal mucosa from colorectal cancer resections. Among 127,865 participants, we documented 270 colorectal cancer cases from which we could assess 15-PGDH expression. Compared with nonuse, regular aspirin use was associated with lower risk of colorectal cancer that developed within a background of colonic mucosa with high 15-PGDH expression [multivariable HR, 0.49; 95% confidence interval (CI), 0.34 to 0.71], but not with low 15-PGDH expression (multivariable HR, 0.90; 95% CI, 0.63 to 1.27) (P for heterogeneity = 0.018). Regular aspirin use was associated with lower incidence of colorectal cancers arising in association with high 15-PGDH expression, but not with low 15-PGDH expression in normal colon mucosa. This suggests that 15-PGDH expression level in normal colon mucosa may serve as a biomarker that may predict stronger benefit from aspirin chemoprevention.