Cystatin C Deficiency Promotes Epidermal Dysplasia in K14-HPV16 Transgenic Mice

Cysteine protease cathepsins are important in extracellular matrix protein degradation, cell apoptosis, and angiogenesis. Mice lacking cathepsins are protected from tumor progression in several animal models, suggesting that the regulation of cathepsin activities controls the growth of various malignant tumors.We tested the role of cathepsins using a mouse model of multistage epithelial carcinogenesis, in which the human keratin-14 promoter/enhancer drove the expression of human papillomavirus type 16 (HPV16) early region E6/E7 transgenes. During the progression of premalignant dysplasia, we observed increased expression of cysteine protease cathepsin S, but concomitantly reduced expression of cathepsin endogenous inhibitor cystatin C in the skin tissue extract. Absence of cystatin C in these transgenic mice resulted in more progression of dysplasia to carcinoma in situ on the face, ear, chest, and tail. Chest and ear skin extract real time PCR and immunoblot analysis, mouse serum sample ELISA, tissue immunohistological analysis, and tissue extract-mediated in vitro elastinolysis and collagenolysis assays demonstrated that cystatin C deficiency significantly increased cathepsin expression and activity. In skin from both the chest and ear, we found that the absence of cystatin C reduced epithelial cell apoptosis but increased proliferation. From the same tissue preparations, we detected significantly higher levels of pro-angiogenic laminin 5-derived γ2 peptides and concurrently increased neovascularization in cystatin C-deficient mice, compared to those from wild-type control mice.Enhanced cathepsin expression and activity in cystatin C-deficient mice contributed to the progression of dysplasia by altering premalignant tissue epithelial proliferation, apoptosis, and neovascularization

Influence of standard heparin or low molecular weight heparin on healing of abdominal wounds and colonic anastomoses in rats

The influence of standard heparin or low molecular weight (LMW) heparin on healing of abdominal wounds and colonic anastomoses was studied in rats. Subcutaneous injection of 1 XaI U/g b.w. of standard or LMW-heparin or 0.5 ml physiologic saline was given 12 hours preoperatively and daily for 3 or 7 days postoperatively. Breaking strength of the abdominal wound and the anastomosis was measured, as were haemoglobin and albumin in serum. Hydroxyproline as a measure of collagen and tissue dry weight was determined in standardized segments of colonic wall adjacent to the anastomosis. Except for significant increase in breaking strength of the anastomosis after 7-day injection of LMW heparin, no differences in the parameters of wound healing were found after 3 or 7 days. In rats receiving standard heparin there was increased bleeding tendency (reduced haemoglobin) compared with the LMW-heparin group and the controls. The administered heparin thus did not negatively influence healing, and standard and LMW-heparin did not differ in this respect