Kosaku Sakamoto

Mutations of the transforming growth factor-β type II receptor gene are strongly related to sporadic proximal colon carcinomas with microsatellite instability

Mutations of the transforming growth factor‐β type II receptor gene (TGF‐β RII) have been found in several replication error‐positive sporadic colorectal carcinomas and hereditary nonpolyposis colorectal carcinoma cell lines. The aim of this study was to clarify the role of TGF‐β RII in sporadic colorectal carcinogenesis.

Explant organ culture: A review

Organ explant culture models offer several significant advantages for studies of patho-physiologic mechanisms like cell injury, secretion, differentiation and structure development. Organs or small explants/slices can be removed in vivo and maintained in vitro for extended periods of time if careful attention is paid to the media composition, substrate selection, and atmosphere. In the case of human tissues obtained from autopsy or surgery, additional attention must be paid to the postmortem interval, temperature, hydration, and cause of death. Explant organ culture has been effectively utilized to establish outgrowth cell cultures and characterize the histiotypic relationships between the various cell types within an organ or tissue.

Adenoma of the rectum with multiple foci of signet-ring cell carcinoma

A case with multiple foci of signet-ring cell carcinoma in an adenoma of the rectum is presented. Four foci of the signet-ring cell carcinoma and four foci of the common type of adenocarcinoma were found independently in a large polypoid tumor. An originating point of one of the signet-ring cell cancer foci was shown by an extensive serial sectioning study.

A pilot study on the usefulness of a new test for mass screening of colorectal cancer in Japan

SummaryA new screening test (Shamsuddin and Elsayed, 1988) based on the enzymatic detection of the disaccharide Β-D-Gal(1→ 3)-D-GalNAc in the rectal mucus of patients with colorectal (CR) cancer and precancerous conditions such as inflammatory bowel disease (IBD) and polyp (precancerous lesions) was evaluated in 85 Japanese patients. Following a 15-minute reaction, a sensitivity of 80.0% (8/10) for CR cancer and 72.2% (8/11) for precancerous lesions was obtained. The overall specificity for combined CR cancers and precancerous lesions was 62.2% (28/45). Correlation with abnormal mucin production in the tissues of CR cancer and precancerous lesions was studied by high-iron diamine-Alcian blue and/or periodic acid-Schiff-Alcian blue (pH= 1.0). The agreement of the results with this test was 77.8% (7/9) for CR cancers and 75.0% (6/8) for precancerous conditions. Because of the simplicity of this test, low cost, stability of the sample and reagents and accuracy for CR cancer and precancerous lesions, the test may have potential use for mass screening of cancer and high risk individuals, particularly CR cancer in Japan.

Carbohydrate Tumor Marker: Basis for a Simple Test for Colorectal Cancer

Large intestinal cancer (LIC) is one of the commonest cancers in the industrialized world. It is ranked among the major causes of cancer death in the United States and other Western countries.1 Because of the magnitude of the health problem and associated cost in life and materials, control of this cancer is vital. Prevention is one of the methods of cancer control, and detection of the cancer at the very early stage of the disease is fundamental to prevention. Early detection in its turn is dependent on screening the population (or those at risk) for the disease. Without screening, a 50-year-old person at average risk has approximately a 530 in 10,000 chance of developing invasive colorectal cancer during the rest of her/his life.2 A host of currently available diagnostic assays have been recommended and are in use for LIC screening.3 The common ones are the fecal occult blood tests (FOBT), barium enema X-rays, and endoscopic visualization.3 The cost-effectiveness of these vary tremendously; their use as screening assays is therefore seriously in question.2–7 On one hand, FOBTs are relatively inexpensive2,3 (approximately

Explant organ culture of hamster alimentary tract epithelium.

10) but are not cost-effective due to their inaccuracies. While the cost of barium enemas and colonoscopies can range from

Verapamil Enhancement of Antitumor Effect of cis-Diamminedichloroplatinum(II) in Nude Mouse-grown Human Neuroblastoma

250–800, they are highly accurate, although marred by the discomfort they cause.

Adenoma of the rectum with multiple foci of signet-ring cell carcinoma. Report of a case.

Adult Syrian Golden hamster alimentary tract maintained as explants in organ culture was studied using the model system for hamster pancreas described by Resau et al. (1983a). Explants of esophagus, stomach, duodenum and colon were maintained in organ culture on Gelfoam® sponge rafts in a high-oxygen atmosphere with serum-supplemented CMRL-1066 medium. All of the tissues were observed to show evidence of sublethal acute cell injury during the first several days of culture. Subsequently, the epithelial tissues recovered from this injury, repopulated the denuded areas of the explants and replicated within the sponge matrix. Explants were maintained in a differentiated state for 30+ days and sampled for morphology to examine the process of cell injury, repair, differentiation and replication which occurs in mucosal epithelia. The percentage of basement membrane covered by epithelia in the explants from various tissues was compared to the level of LDH in the media to reveal the relationship between viability determined by biochemical and by morphological methods. Restitution of the mucosal surface occurred in all of the explants. We conclude that adequate populations of replicating cells are maintained within the epithelium of the hamster alimentary tract tissues in vitro so that restitution can occur through migration and subsequent differentiation of the epithelial cells within the mucosa of the explants.