No abstract

Midkine (MK) is a growth/differentiation factor frequently expressed at high levels in some types of human malignancies. To investigate whether MK is a useful marker in prostate carcinogenesis, immunohistochemical analysis was performed on samples of both latent and clinical prostate cancers of various stages, as well as on specimens of normal gland and prostatic intraepithelial neoplasia (PIN). Of the 80 clinical cancers examined, 69 specimens (86.3%) were immunoreactive for MK, with metastatic lesions generally showing higher expression than the corresponding primaries; normal prostate tissues were negative or showed only weak staining. Midkine was also detected in 12 of 15 latent cancers (80%) and in 12 of 16 cases of PIN (75%). In sections of whole prostate, MK showed variable expression through tumorous sections, probably in reflection of heterogeneous cell populations. The results demonstrate the possible value of MK as a marker for early and latent disease, as well as for more advanced clinical stages of prostate cancer.

The effect of hypertonic saline resuscitation on intestinal damage and the incidence of apoptosis after hemorrhagic shock were investigated. After anesthesia, male BALB/c mice weighing 24-34 g were hemorrhaged to the mean arterial pressure of 40 +/- 5 mmHg for 90 min. Animals were randomly assigned to four groups: 1) resuscitation with 4 mL/kg of 7.5% NaCl (hypertonic saline; HS) + shed blood (SB); 2) resuscitation with two times the volume of shed blood of lactated Ringer's solution (2LR) + SB; 3) sham (catheter only); or 4) control (no treatment). Intestinal damage was graded based on the extent of the vacuolation at the basal area of the intestinal villi. Apoptosis of the small intestines was examined with the terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling method and with DNA laddering. Caspase-3 activation, heat shock protein (HSP) 70, and HSP40 were assessed by western blotting. Apoptosis of the small intestine and intestinal damage were significantly lower (P < 0.01) in the HS+SB group compared with the 2LR+SB group 2 h and 6 h after hemorrhagic shock and resuscitation, respectively. This corresponded with more DNA fragmentation in the small intestine of the 2LR+SB group compared with the HS+SB group 2 h after hemorrhage and resuscitation. In addition, we observed less caspase-3 activation in the small intestine of the HS+SB group compared with the 2LR+SB group at 2 h after resuscitation. The content of HSP40 and HSP70 in the HS+SB group was similar to that in controls, but slightly decreased in the 2LR+SB group. HS resuscitation reduced intestinal damage and apoptosis after hemorrhagic shock, suggesting that HS resuscitation may improve the outcome after hemorrhagic shock by reducing apoptosis and damage to the small intestine.

The E-cadherin–catenin complex plays an important role in establishing and maintaining intercellular connections and morphogenesis and reduced expression of its constituent molecules is associated with invasion and metastasis. In the present study, we examined E-cadherin and α-, β- and γ-catenin levels in tumour tissues obtained by radical prostatectomy in order to investigate the relationship with histopathological tumour invasion. Immunohistochemical findings for 45 prostate cancer specimens demonstrated aberrant expression of each molecule to be associated with dedifferentiation and, in addition, alteration of staining patterns for the three types of catenin was significantly correlated with capsular but not lymphatic or vascular invasion. The data thus suggest that three types of catenin may be useful predictive markers for biological aggressiveness of prostate cancer. © 1999 Cancer Research Campaign

Long-term in vivo carcinogenicity tests of potassium bromate (KBrO3), sodium hypochlorite (NaClO), and sodium chlorite (NaClO2) have been conducted in Japan from 1977 to 1985. In these investigations, groups of approximately 50 male and 50 female F344 rats or B6C3F1 mice were given solutions of the compounds as their drinking water ad libitum at two dose levels determined on the basis of preliminary 13-week tests. Control animals were given distilled water.The carcinogenic potential of KBrO3 was tested by administering doses of 500 or 250 ppm to rats for 110 weeks. Significantly elevated incidences of renal cell tumors in males and females and mesotheliomas of the peritoneum in males as compared to controls were observed. When female mice were given KBrO3 at doses of 1000 or 500 ppm for 78 weeks, no significant differences in tumor incidences between experimental and control groups were apparent.NaClO was administered to male and female rats, respectively, at doses of 1000 or 500 ppm and 2000 or 1000 ppm for 104 weeks. In mice, NaClO was given at doses of 1000 or 500 ppm to either sex for 103 weeks. The incidences of tumors in NaClO-treated and control animals of both sexes were not significantly different in both rat and mouse studies.NaClO2 was given to rats of both sexes at a dose of 600 or 300 ppm for 85 weeks. No statistically significant differences were observed in the incidences of tumor formation between NaCI02-treated and control groups of both sexes. NaCI02 was administered to mice at a concentration of 500 or 250 ppm for 85 weeks. In males, the combined incidences of hyperplastic nodules and hepatocellular carcinomas of the liver in a low-dose group, and adenomas and adenocarcinomas of the lung in a high-dose group, were marginally increased compared to controls (p<0.05). However, these incidences in treated males were within the range of values of historical control data in our program.We concluded that KBrO3 was carcinogenic in rats of both sexes. NaClO was not carcinogenic in either rats and or mice under the conditions of the present studies. Although NaClO2 was shown to be noncarcinogenic in rats, the results for mice were evaluated as inconclusive. Also the results of two-stage mouse skin carcinogenesis using KBrO3, NaClO, and NaCl02 are presented. The necessity for further testing of oxidant chemicals to determine potential carcinogenic and/or promoting effects is suggested in view of the recently proposed role of active oxygen species in carcinogenesis.