Grape antioxidant dietary fiber inhibits intestinal polyposis in ApcMin/+ mice: relation to cell cycle and immune response.

Epidemiological and experimental studies suggest that fiber and phenolic compounds might have a protective effect on the development of colon cancer in humans. Accordingly, we assessed the chemopreventive efficacy and associated mechanisms of action of a lyophilized red grape pomace containing proanthocyanidin (PA)-rich dietary fiber [grape antioxidant dietary fiber (GADF)] on spontaneous intestinal tumorigenesis in the Apc(Min/+) mouse model. Mice were fed a standard diet (control group) or a 1% (w/w) GADF-supplemented diet (GADF group) for 6 weeks. GADF supplementation greatly reduced intestinal tumorigenesis, significantly decreasing the total number of polyps by 76%. Moreover, size distribution analysis showed a considerable reduction in all polyp size categories [diameter <1mm (65%), 1-2mm (67%) and >2mm (87%)]. In terms of polyp formation in the proximal, middle and distal portions of the small intestine, a decrease of 76, 81 and 73% was observed, respectively. Putative molecular mechanisms underlying the inhibition of intestinal tumorigenesis were investigated by comparison of microarray expression profiles of GADF-treated and non-treated mice. We observed that the effects of GADF are mainly associated with the induction of a G1 cell cycle arrest and the downregulation of genes related to the immune response and inflammation. Our findings show for the first time the efficacy and associated mechanisms of action of GADF against intestinal tumorigenesis in Apc(Min/+) mice, suggesting its potential for the prevention of colorectal cancer.

Ileal Vanek's tumor mimicking cecal carcinoma.

Inflammatory fibroid polyps or Vanek's tumors are rare benign pseudotumoral lesions with morphological characteristics similar to those of submucosal mesenchymal tumors. They have been described in the gastrointestinal tract, most frequently in the gastric antrum. We present a case of ileal Vanek's tumor associated with a raised carcinoembryonic antigen level and with radiological and endoscopic features mimicking cecal carcinoma.

Carcinoembryonic antigen: clinical and historical aspects.

To further define and determine the usefulness of CEA, 1100 CEA determinations have been made over the past two years at The Ohio State University Hospitals on patients with a variety of malignant and nonmalignant conditions. Correlation of CEA titers with history and clinical course has yielded interesting results not only in cancers of entodermally derived tissues, for which CEA has become an established adjunct in management, but also in certain other neoplasms and inflammatory states. The current total of 225 preoperative CEA determinations in colorectal carcinomas shows an 81% incidence of elevation, with postoperative titers remaining elevated in patients having only palliative surgery but falling to the negative zone after curative procedures. An excellent correlation exists between CEA levels and grade of tumor (more poorly differentiated tumors showing lower titers). Left-side colon lesions show significantly higher titers than right-side lesions. CEA values have been shown to be elevated in 90% of pancreatic carcinomas studied, in 60% of metastatic breast cancers, and in 35% of other tumors (ovary, head and neck, bladder, kidney, and prostate cancers). CEA levels in 35 ulcerative colitis patients show elevation during exacerbations (51%). During remissions titers fall toward normal, although in 31% still remaining greater than 2.5 ng/ml. In the six colectomies performed, CEA levels all fell into the negative zone postoperatively. Forty percent of adenomatous polyps showed elevated CEA titers (range 2.5-10.0) that dropped following polypectomy to the negative zone. Preoperative and postoperative CEA determinations are important in assessing the effectiveness of surgery. Serial CEA determinations are important in the follow-up period and in evaluation of the other modes of therapy (e.g., chemotherapy). These determinations of tumor antigenicity give the physician added prognostic insight into the behavior of the tumor growth. Rectal examination with guaiac determinations, sigmoidoscopy, cytology, barium enema, and a good clinical evaluation remain the primary tools for detecting colorectal disease. However, in the high-risk patient suspicious of developing cancer, CEA determinations as well as colonoscopy are now being used increasingly and provide additional highly valuable tools in the physician's armamentarium.