A case of bullous pemphigoid in a patient on hemodialysis.

We describe a case of bullous pemphigoid (BP) in a patient with chronic renal failure maintained on hemodialysis. We diagnosed BP by histopathological and immunofluorescence studies. The relationship between BP and chronic renal failure and/or hemodialysis is not clear, but we believe that immune disarrangement due to chronic renal failure and/or hemodialysis may have influenced the pathogenesis of BP in our case.

Apoptosis induced by NS-398, a selective cyclooxygenase-2 inhibitor, in human colorectal cancer cell lines.

Recent studies have suggested that apoptosis is a key phenomenon in the chemopreventive action of nonsteroidal antiinflammatory drugs (NSAIDs), which exhibit cancer-preventive and tumor-regressive effects in the human colon. The effect of NS-398, N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide, which is a selective inhibitor of cyclooxygenase-2 (COX-2), on the induction of apoptosis in two human colorectal cancer cell lines (Colo320 and THRC) was determined. The apoptotic ratios (-fold vs. control value) of Colo320 in the presence of 100 microM indomethacin and NS-398 were 3.3 +/- 1.5 and 9.0 +/- 0.94, and those of THRC were 2.3 +/- 0.46 and 7.4 +/- 0.87, respectively. The ability of NS-398 to induce apoptosis is greater than that of indomethacin. Both indomethacin and NS-398 reduced the cell proliferation in a concentration-dependent manner. The IC50 values of NS-398 (54.8 +/- 3.6 and 77.2 +/- 4.9 microM) were significantly lower than those of indomethacin (206.3 +/- 43.0 and 180.3 +/- 22.6 microM) at P < 0.01 in Colo320 and THRC cell lines, respectively. These findings suggest that NS-398, a selective inhibitor of COX-2, is a possible candidate for a chemopreventive agent with a potent apoptosis-inducing effect and low ulcerogenic activity.

Inhibitory effects of dietary protocatechuic acid and costunolide on 7,12-dimethylbenz[a]anthracene-induced hamster cheek pouch carcinogenesis.

The modifying effects of dietary exposure to two natural products, protocatechuic acid (PCA) and costunolide during the development of neoplasms in oral carcinogenesis initiated with 7,12-dimethylbenz[a]anthracene (DMBA) were investigated in male Syrian golden hamsters. All hamsters except those in the test chemical alone and control groups received DMBA (0.5%) in mineral oil to the right buccal pouch 3 times per week for 4 or 6 weeks. At 13 weeks of age, the groups exposed to DMBA were fed diet containing PCA or costunolide at a dose of 0.2 g/kg diet (200 ppm) for 17 weeks. The other groups consisted of hamsters given mineral oil alone for 6 weeks, or given 200 ppm PCA or costunolide alone, or untreated. All animals were necropsied at the termination of the experiment (week 24). PCA or costunolide significantly decreased the tumor burden (P < 0.001-P < 0.05) and the extent of dysplastic areas (%) (P < 0.001-P < 0.05). PCA significantly decreased the mean number of AgNORs/nucleus (P < 0.05). The BrdUrd-labeling index was reduced by dietary administration of test compounds, though not significantly. These results suggest that PCA and costunolide inhibited hamster buccal pouch carcinogenesis and such inhibition may be related to suppression of cell proliferation in the buccal mucosa. It was also found that telomerase activity expressed in neoplastic and preneoplastic lesions of hamster buccal pouch epithelium after DMBA treatment correlated with the histopathological degree of malignancy.

WAF1 expression and p53 mutations in human colorectal cancers.

The expression of the WAF1 gene was examined in the tissues of primary colorectal cancers and of adjacent non-neoplastic mucosas by Western blot analysis. p53 mutations of these cancer tissues were also analyzed by the polymerase chain reaction/single-strand conformation polymorphism followed by direct sequencing. Missense mutations of p53 were recognized in 19 out of 40 cases. Five cancers (12.5%) displayed much lower expression of WAF1 than did their corresponding mucosas, and all of them contained mutant p53. Fourteen cancers (35%) expressed the same level of WAF1 as their mucosas, and 5 of them had mutant p53. Twenty-one cancers (52.5%) had much higher WAF1 expression than their mucosas, and 9 of them had mutant p53. When Duke's classification was applied to these colorectal cancers, it was found that the cancers with reduced expression of WAF1 basically coincided with late (C or D) stages (4 out of 5 cases), while the cancers with higher WAF1 expression were consistent with early (A or B) stages (17 out of 21 cases). Down-regulation of WAF1 in colorectal cancer tissues may be implicated in tumor progression.

Overexpression of cyclin B1 in human colorectal cancers.

The expression of the human cyclin B1 gene was investigated with Western blot analysis in human colorectal carcinomas and in adjacent non-neoplastic colorectal mucosas. Out of 41 cancers, 36 (88% of patients) showed much higher expression of cyclin B1 than did the non-neoplastic mucosa. Proliferating-cell nuclear antigen (PCNA) immunohistochemistry revealed that the labeling indexes of these cancer tissues were 47.3 +/- 11.3% while those of the mucosa were 15.6 +/- 5.5%. Only 5 cancers (12% patients) demonstrated the same expression level of cyclin B1 as the mucosa; however, the PCNA labeling indexes were 42.3 +/- 11% for the cancer tissue, compared to 12.6 +/- 2.4% for the mucosas. Southern blot analysis showed that there was no change of the cyclin B1 gene at the somatic DNA level in spite of its high expression at the protein level. These results proved that majority of colorectal cancers express high levels of cyclin B1, consistent with a high rate of cell proliferation, whereas a small fraction of these cancers lose control of cyclin B1 expression, diverging from their fast cell proliferation.

Immunoadsorption for the treatment of bullous pemphigoid.

We treated 2 intractable patients with pemphigoid by absorbent plasmapheresis using dextran sulfate conjugated cellulose columns with an automated regenerating unit. During a 2 week period, this plasmapheresis was performed 4 to 6 times for Cases 1 and 2, respectively. Clinical findings including skin eruptions were remarkably improved, and the titers of antibasement membrane zone antibodies were decreased after the treatment of 1.8 to 4.2 L of plasma. These results suggest that the absorbent column is effective for intractable pemphigoid.

Lack of inhibitory effect of benzyl isothiocyanate on 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP)-induced mammary carcinogenesis in rats.

Modifying effects of benzyl isothiocyanate (BITC), a glucosinolate compound, were investigated on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced mammary carcinogenesis in female SD rats. One hundred twenty five female rats were divided into 4 groups. Starting at 6 weeks of age, rats were fed high fat diet containing 23.5% corn oil (Groups 1 and 4) or the experimental diet (high fat diet with 400 ppm BITC) (Groups 2 and 3). At 7 weeks of age, Groups 1 and 2 were given PhIP (100 mg/kg body weight, 8 times for 16 days) by intragastric tube. One week after the final PhIP treatment, the experimental diet for Groups 2 and 3 switched to high fat diet. At the termination (31 weeks after the start of experiment), mammary adenocarcinomas were recognized in Group 1 (PhIP alone) and Group 2 (PhIP + BITC). The incidence of neoplasms was 74.2% in Group 1, and 62.5% in Group 2. The multiplicity of them was 1.71 +/- 1.70 in Group 1, and 1.91 +/- 2.94 in Group 2. Mean sizes of tumors were 9.9 +/- 7.1 mm in Group 1, and 10.8 +/- 6.8 mm in Group 2. But no significant differences for tumors were available between the two groups. These results imply that the glucosinolate compound does not have clear inhibitory effects on PhIP-induced mammary carcinogenesis in rats.

Telomerase activity of normal tissues and neoplasms in rat colon carcinogenesis induced by methylazoxymethanol acetate and its difference from that of human colonic tissues.

Telomerase activity in tissues may be related to tumor development, especially malignant conversion, in humans. However, there are few reports about telomeres and telomerase activity in animals. In this study, we examined telomerase activity in rat colon carcinogenesis and in normal rat liver tissue and compared it with that of human colon cancer tissues. This is the first report concerning telomerase activity in rats. F344 rats were used, and colon neoplasms were induced with methylazoxymethanol acetate. There was telomerase activity in not only the induced colon neoplasms but also the colon mucosa and livers of untreated rats, in contrast with the results from normal human somatic tissues in previous reports. Indeed, we also observed negative results in normal human mucosa, despite the positive results in colon-cancer tissues. These findings suggest that there is a difference in the telomerase activities in humans and rats. Because rat telomeres are very long (20-100 kp, average 50 kp) compared with human telomeres (5-15 kp, average 12 kp), the difference in the telomere lengths of rats and humans might be related to their enzyme activities, although this is still unclear. Furthermore, because the inhibition of telomerase has been proposed as a novel cancer therapy for humans, the rat model presented here, in which telomerase is expressed in somatic tissues, may be useful for studies of telomerase inhibition, including inhibition by chemopreventive agents.

Toxicity and tumorigenicity of purpurin, a natural hydroxanthraquinone in rats: induction of bladder neoplasms.

Chronic toxicity and tumorigenicity of purpurin, a natural hydroxyanthraquinone, was examined in two groups of male F344 rats. One group was given a basal diet mixed with purpurin at a concentration of 1% throughout the experiment (520 days). Another group was kept on the basal diet without purpurin during the experiment. Almost all animals given purpurin developed conspicuous changes of kidney resembling 'progressive chronic nephropathies', the severity and frequency of which were much stronger than in controls. In rats with purpurin treatment, marked hyperplasia of pelvic epithelium was frequently seen and several rats developed urinary bladder tumors (papilloma and carcinoma). Prominent crystallization in the renal pelvis and urinary bladder seems to be initially related to the toxic effects of this hydroxanthraquinone on the renal tubules and with the occurrence of epithelial hyperplasia and neoplasms.

The mRNA overexpression of inflammatory enzymes, phospholipase A2 and cyclooxygenase, in the large bowel mucosa and neoplasms of F344 rats treated with naturally occurring carcinogen, 1-hydroxyanthraquinone.

Inflammation has been considered to be related to carcinogenesis. Previously, we demonstrated that 1-hydroxyanthraquinone (1-HA), a naturally occurring carcinogen, induced severe inflammation such as ulcerative colitis in colonic mucosa. We also showed that indomethacin inhibited the tumorigenicity of 1-HA. In this study, we examined the expressions of major enzymes in arachidonic acid cascade related to inflammation in the colon mucosa of rats treated with 1-HA. After the treatment of 1% 1-HA diet, colon lesions were observed and RNA was extracted from mucosa and neoplasms. The mRNA expressions of group II phospholipase A2, cyclooxygenase-2 and 5-lipoxygenase, were examined by using a reverse transcriptase polymerase chain reaction. The expressions of phospholipase A2 and cyclooxygenase were significantly increased in non-neoplastic mucosa in rats treated with 1-HA compared with those in control rats. The expressions in the neoplasms induced by 1-HA were also increased. Phospholipase A2, especially, was much higher in the neoplasms than in non-neoplastic mucosa. However, the expression of 5-lipoxygenase showed no change in the non-neoplastic mucosa and neoplasms of rats treated with 1-HA, compared with that in control rats. These findings suggest that the inflammation induced by 1-HA may be related to the metabolites through a cyclooxygenase pathway, which indicates a prostaglandin synthesis, but not through a lipoxygenase pathway, which indicates a leukotriene synthesis in arachidonic acid cascade.

DNA fragmentation in granular cells of human cerebellum following global ischemia.

Vulnerability of human cerebellum in two autopsy cases following global brain ischemia was examined histologically by using a specific in situ nick-end labeling method for DNA breaks. In both cases, DNA fragmentation was observed in approximately one-third of the granular cells in cerebellar cortex, whereas Purkinje cells were still alive and no DNA fragmentation was recognized in the nuclei. The present study suggests that some granular cells of cerebellar cortex are more vulnerable to transient ischemia than Purkinje cells and death of granular cells is induced by an apoptotic DNA fragmentation following global brain ischemia.

Acute and subacute toxicity tests of madder root, natural colorant extracted from madder (Rubia tinctorum), in (C57BL/6 X C3H)F1 mice.

As part of the safety assessment of madder root (MR), a food colorant extracted from madder (Rubia tinctorum), toxicity tests were undertaken using (C57BL/6 x C3H)F1 mice of both sexes. An acute toxicity test was performed by 14-day administration of MR dissolved in distilled water by gavage at doses of 0, 500, 2000, 3500, and 5000 mg/kg body weight to groups of each sex. One male mouse dosed at 5000 mg/kg body weight was dead before the end of the study, indicating that the maximum tolerated dose of MR was between 3500 and 5000 mg/kg body weight. A subacute toxicity test of MR was performed using 62 mice of each sex, mixing their diets with MR at concentrations of 0, 0.3, 0.6, 1.25, 2.5, and 5% for 90 days. All mice tolerated these doses of MR well. The body weight gains of either sex were not affected by the treatment. None of the mice treated with MR showed clinical signs of toxicity. Histopathological examinations showed retention cysts of the kidneys and epidermal vaginal cysts in a few of the treated or control mice. No hyperplastic, preneoplastic, and neoplastic lesions and no pathological findings of toxicity were found. These results suggest that dietary exposure of MR at these doses has no acute or subacute toxic effects on mice.