Analysis of ODC and c-myc gene expression in hepatocellular carcinoma by in situ hybridization and immunohistochemistry.

We quantitated mRNA and protein for ornithine decarboxylase (ODC) and c-myc in formalin-fixed liver sections from 25 specimens of hepatocellular carcinoma (HCC) and seven normal livers by a non-radiolabeled in situ hybridization technique and immunohistochemistry. This non-radioactive in situ hybridization technique was highly specific, with virtually no background, and permitted quantitative analysis based on optical density. Reaction products were quantitated with computer-assisted microdensitometry. Samples were classified as normal, adjacent uninvolved, cirrhosis, well-differentiated HCC, and poorly-differentiated HCC. There was a progressive increase in all four parameters measured, ODC mRNA and protein, and c-myc mRNA and protein, from normal, to adjacent uninvolved liver, to cirrhosis, to well-differentiated HCC, to poorly-differentiated HCC. The sole exception was that ODC mRNA was lowest in cirrhosis. The patterns of ODC and c-myc gene expression are similar in HCC. The quantitative detection of ODC mRNA, c-myc mRNA, and their protein products in hepatocellular carcinoma and cirrhosis by in situ hybridization and immunohistochemical techniques may have a potential role in the study of hepatocarcinogenesis and in the diagnosis of hepatocellular carcinoma.

Adenoma-derived antibody, Adnab-9 recognizes a membrane-bound glycoprotein in colonic tissue and effluent material from patients with colorectal neoplasia.

The binding in pre-colonoscopic effluent of Adnab-9, a monoclonal antibody raised against colonic adenomas, was evaluated for specificity in the diagnosis of colorectal cancer. A heterogeneous group of 58 patients was evaluated by ELISA. Effluent samples and tissue extracts were subjected to Western blotting or ELISA to confirm specificity. Immunohistochemistry was performed on the cancer tissue sections. The proportion of positive effluent binding was higher in the cancer when compared to the normal group (P = 0.036). A dominant 87 M(r) band was found in adenoma extracts and some effluent samples. Adnab-9 binding in effluent samples predominated in membrane-bound fractions. Immunohistochemistry showed no specific staining in the cancer cells. The antigen recognised is a glycoprotein shown by effects of N-glycanase digestion and not cross-reactive with carcinoembryonic antigen. Non-gastro-intestinal tissue extracts did not bind Adnab-9. The major 87 M(r) adenoma-derived antigen may be found in effluent material, particularly in the membrane-bound fraction.

Cellular distribution of a colonic adenoma-associated antigen as defined by monoclonal antibody Adnab-9.

Adenomatous colonic polyps constitute a precursor for colorectal cancer. Antibodies to these precancerous lesions might identify specific early tumor antigens. Adnab-9 is a murine monoclonal antibody raised against membranes of colonic adenomas. Adnab-9 binding in colonic washings (effluent) correlates with the presence of colorectal cancer. Immunohistochemical staining with Adnab-9 shows cytoplasmic reactivity in scattered cells in 4 of 31 adenomatous tissue sections, 0 of 14 sections of colorectal cancer cells, and 1 of 8 normal-appearing colonic mucosa specimens examined. Adnab-9 recognized a dominant M(r) 87,000 protein species in tissue extracts in the membrane-bound fraction of effluent by Western blotting. Adnab-9 binding by enzyme-linked immunosorbent assay in adenomatous extracts is higher than cancer or normal tissue, is membrane-bound, and is absent from established colorectal cancer cell lines. This distribution and nature of immunostaining suggest that Adnab-9 recognizes a determinant associated with the membrane component of a subpopulation of adenoma cells which may have a role in early colorectal neoplasia.

Detection of ornithine decarboxylase messenger RNA in human hepatocellular carcinoma by in situ hybridization.

Ornithine decarboxylase (ODC) has been shown by biochemical analysis, to be important for cell proliferation and carcinogenesis in a variety of tissues, including the liver. We detected messenger RNA (mRNA) specific for the enzyme ODC in 18 patients with hepatocellular carcinoma by an in situ hybridization technique using a radiolabelled ODC probe on formalin-fixed liver specimens. Adjacent uninvolved liver tissues were used as controls. Among the adjacent uninvolved liver tissues, five showed evidence of cirrhosis. Poorly differentiated hepatocellular carcinoma has significantly higher levels of ODC mRNA than does well-differentiated hepatocellular carcinoma, which in turn has a significantly higher ODC mRNA level than adjacent uninvolved liver tissues; tissues showing evidence of cirrhosis, on the other hand, had a significantly lower ODC mRNA level than adjacent uninvolved liver tissue. This pattern of ODC gene expression in hepatocellular carcinoma is similar to the pattern of expression of other oncogenes in liver tumours. The quantitative detection of ODC mRNA in hepatocellular carcinoma by in situ hybridization may help elucidate the potential role of ODC in hepatocarcinogenesis.

Splenic trauma during colonoscopy.

A case of splenic rupture following therapeutic colonoscopy is described, and previously reported cases are reviewed. The occurrence of this event and the associated circumstances are often unpredictable. A high index of suspicion is the key to the diagnosis of this rare but potentially lethal complication.

Paroxysmal cold hemoglobinuria in a patient with Klebsiella pneumonia.

A case of paroxysmal cold hemoglobinuria (PCH) occurring in a patient with Klebsiella pneumonia is described. The first sign of PCH in the patient was erythrophagocytosis. The Donath-Landsteiner (D-L) antibody exhibited anti-P specificity both serologically and biochemically. The appearance of D-L antibody during fulminating Klebsiella pneumonia strongly suggests their causal relationship.

Combined inhibitors of carcinogenesis: effect on azoxymethane-induced intestinal cancer in rats.

Outbred male Sprague-Dawley CD rats were fed a complete semisynthetic diet and were given supplemental low doses (2 ppm) of selenium as H2SeO3 in their drinking water or 50 mg 13-cis-retinoic acid (13-cis-RA) and 2 g beta-sitosterol/kg diet either singly, in combinations of two, or in combinations of all three. Intestinal tumors were induced with eight weekly sc injections of 8 mg azoxymethane (AOM)/kg body weight, and inhibition of tumor formation was determined by tumor counts after 26 weeks. Noncarcinogen controls for each dietary group received eight injections of sterile water. Tumor inhibition was statistically significant in 2 groups of animals: Dietary control animals had a tumor frequency of 5.07 tumors/rat, rats receiving selenium- plus 13-cis-RA supplementation had a tumor frequency of 3.77, and those being given the combination of all three inhibitors had 2.75 tumors/rat. Analysis of fecal steroids from 3 AOM groups (dietary controls, the beta-sitosterol plus 13-cis-RA-supplemented group, and the group receiving all three additives) after 4 months of supplementation showed that the addition of beta-sitosterol to the diet had no effect on acidic or neutral steroids, regardless of the observed difference in tumor frequency. These results suggest that subpharmacologic doses of inhibitors, particularly those that inhibit the process by different mechanisms, while ineffective alone, may provide significant inhibition of tumorigenesis when used in combination.