Effects of PTK787/ZK 222584, a specific inhibitor of vascular endothelial growth factor receptor tyrosine kinases, on primary tumor, metastasis, vessel density, and blood flow in a murine renal cell carcinoma model

Antiangiogenic therapy is a promising new strategy to inhibit tumor growth and formation of metastases. Vascular endothelial growth factor (VEGF) and its receptors, VEGF-receptor 1 (VEGF-R1; FLT-1) and VEGF-R2 (KDR), have been shown to play a major role in tumor angiogenesis. PTK787/ZK 222584, a specific inhibitor of both VEGF-receptor tyrosine kinases, was investigated for its antitumoral and antiangiogenic activity in a murine renal cell carcinoma model. After intrarenal application of the renal carcinoma cells, mice develop a primary tumor and metastases to the lung and to the abdominal lymph nodes. Daily oral therapy with PTK787/ZK 222584 at a dose of 50 mg/kg resulted in a significant decrease of 61 and 67% in primary tumors after 14 and 21 days, respectively. The occurrence of lung metastases was significantly inhibited at both time points (98% reduction and 78% reduction, respectively). After 14 days, no lymph node metastases developed in the PTK787/ZK 222584-treated group, whereas after 21 days of treatment, the lymph node metastases were reduced by 87%. Vessel density in tumor tissues, detected by immunohistochemistry with an anti-CD31 antibody, was significantly decreased by PTK787/ZK 222584. Using color Doppler imaging ultrasound, significant changes in blood flow in the tumor feeding renal artery were found under treatment with PTK787/ZK 222584. Blood flow changes correlated with changes in vessel density but not with tumor volume. The compound was well tolerated in all in vivo experiments and had no significant effects on body weight or general well-being of the animals. This was in contrast to the animals treated with the antiangiogenic agent TNP-470. s.c. therapy with 30 mg/kg TNP-470 every other day had to be discontinued after 13 days because of animal weight loss (>20%) and ataxia. These results demonstrate that PTK787/ZK 222584 is a potent inhibitor of tumor growth, metastases formation, and tumor vascularization in murine renal cell carcinoma. Furthermore, we have been able to demonstrate that color Doppler imaging ultrasound can be used to measure blood flow to a tumor and that flow correlates with vessel density. Thus, this may be a valuable noninvasive method for monitoring the effects of antiangiogenic agents such as PTK787/ZK 222584 on tumor vasculature.

[Perspectives of patients with terminal renal failure: quality of life and psychological adjustment before and in the first year after heart transplantation]

This prospective study was designed to compare quality of life, life satisfaction, and subjective ratings of health before and at variable time intervals after heart transplantation (HTx). 175 patients were included between February 1994 and December 1997. Every six months before and 1 1/2, 3, 6, and 12 months after HTx, they received the following standardized and validated questionnaires: German SF 36, heart failure and specific transplant symptom list, global quality of life assessment, Munich life quality dimension list, expected/experienced life changes after HTx. Inclusion criteria were the acceptance of the patient on the waiting list for HTx, good command of the German language, and a minimum age of 18 years. During data evaluation, median (Me), mean (M), and standard deviation (SD) were created from individual parameters. Quality of life was rated as very poor by 84% of patients with congestive heart failure. Only 6 weeks after HTx, 74% rated their quality of life as significantly better. Before HTx 80% were very unsatisfied about their health status and 87% about physical performance. Six weeks after HTx, this parameter improved significantly and 76% were very satisfied about their health status and 50% about physical performance. While somatic changes expected before HTx corresponded well with experienced ones, psychological improvements were smaller than expected, but one year after HTx they were significant (before: M = 3.66; SD = 0.9; Range (R) = 3.78 vs 12 months postop: M = 4.61; SD = 0.6; R = 2.67; p < 0.05). Quality of life correlated before HTx best with subjectively rated health (r = 0.61, p < 0.01) and 6 months after with satisfaction about health status (r = 0.76, p < 0.01). Only in 25% were expected improvements fulfilled regarding sexual activity/satisfaction, professional situation, and recreational activities. 90% of post-transplant patients reported physical complaints, most by effects of immunsuppression, but were coping well. The study shows that already 6 weeks after successful HTx all quality of life parameters improved significantly. Despite some unfulfilled expectations and complaints, the postoperative life situation of HTx patients appeared significantly improved.