Alexander Kugler

Regression of human metastatic renal cell carcinoma after vaccination with tumor cell-dendritic cell hybrids

Reports of spontaneous regressions of metastases and the demonstration of tumor-reactive cytotoxic T lymphocytes indicate the importance of the hosts immune system in controlling the devastating course of metastatic renal cell carcinoma. Recent research indicates that immunization with hybrids of tumor and antigen presenting cells results in protective immunity and rejection of established tumors in various rodent models. Here, we present a hybrid cell vaccination study of 17 patients. Using electrofusion techniques, we generated hybrids of autologous tumor and allogeneic dendritic cells that presented antigens expressed by the tumor in concert with the co-stimulating capabilities of dendritic cells. After vaccination, and with a mean follow-up time of 13 months, four patients completely rejected all metastatic tumor lesions, one presented a ‘mixed response’, and two had a tumor mass reduction of greater 50%. We also demonstrate induction of HLA-A2-restricted cytotoxic T cells reactive with the Muc1 tumor-associated antigen and recruitment of CD8+ lymphocytes into tumor challenge sites. Our data indicate that hybrid cell vaccination is a safe and effective therapy for renal cell carcinoma and may provide a broadly applicable strategy for other malignancies with unknown antigens.

EXPRESSION OF METALLOPROTEINASE 2 AND 9 AND THEIR INHIBITORS IN RENAL CELL CARCINOMA

Degradation of the extracellular matrix is necessary for invasion and metastasis by cancer cells. Two gelatinolytic matrix metalloproteinase enzymes, MMP-2 and MMP-9, are supposed to be key enzymes in this process. The purpose of this study was to correlate the presence of MMP-2, MMP-9 and their inhibitors with the tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2 RNA using reverse transcriptase PCR technique with tumor stage in 17 samples of renal cell carcinoma. The ratio of tissues expressing MMP-2 and MMP-9 to those expressing TIMP-1 and TIMP-2 was defined to be 1 in normal kidney tissue. This MMP:TIMP ratio was significantly increased to 2.43 (standard deviation, SD = 0.8) in locally confined renal cell carcinoma and to 4.86 (SD = 1.1) in advanced carcinoma (p <0.01). In primary tumor cell lines the ratio of MMP:TIMP expression was 3.44 (SD = 0.6). These data suggest that the balance of MMP-2 and MMP-9 to TIMP-1 and TIMP-2 expression is an essential factor in the aggressiveness of renal cell carcinoma.

Matrix Metalloproteinases and Their Inhibitors

Matrix metalloproteinases (MMPs) are a group of 16 enzymes that are capable of degrading extracellular matrix components. Their catalytic function is dependent on a zinc ion in the active center. MMPs are separated in three groups: gelatinases (type IV-collagenases), stromelysins, and interstitial collagenases. Their physiological and pathological significance is to modulate the extracellular matrix-e. g., in embryogenesis, in the ovarian cycles, or in inflammatory diseases such as rheumatoid arthritis or fibrosis of the liver or kidney (1,2).

Vascular endothelial growth factor expression, angiogenesis, and necrosis in renal cell carcinomas

Rapidly growing tumors often develop necrosis. In the present study the expression of vascular endothelial growth factor (VEGF) was investigated and compared to microvessel density and necrosis of renal cell carcinomas. In the tumor-host interface the microvessel density was significantly increased compared to central tumor areas. Tumor necrosis was associated with a decrease of microvessel density and an increase of the VEGF protein expression within the perinecrotic rim. VEGF protein was focally upregulated in vital tumor tissue. An increase of the apoptotic rate of endothelia and vital tumor tissue in tumors with necrosis could not be detected. VEGF(121,165) mRNA was decreased in proliferatively active carcinomas compared to less proliferative tumors. Multicellular renal cell cancer spheroids as a model of chronic hypoxia developed central apoptosis but no necrosis. VEGF was upregulated in the spheroid. Tumor microvessels expressed matrix metalloproteinase -2 and -9 and an incomplete pericyte covering in comparison to tumor-free tissue indicating immature active angiogenesis. We conclude that highly proliferative renal cell carcinomas outgrow their vascular supply and develop chronic hypoxia inducing a decrease of proliferation and an increase of VEGF expression. However, chronic hypoxia does not cause significant necrosis or apoptosis. Tumor necrosis is more likely induced by acute hypoxia due to immature microvessels. Furthermore, VEGF expression associated with concomitant tumor necrosis may help identify renal cell carcinomas susceptible to antiangiogenic therapy.

Expression of VCAM-1, ICAM-1, E- and P-selectin and tumour-associated macrophages in renal cell carcinoma.

Neoangiogenesis is accompanied by an increase in endothelial surface, which can support infiltration by immune cells depending on adhesion molecule expression. Therefore, the expression of cell adhesion molecules on microvessels and epithelial cells was analysed in renal cell carcinomas as compared to tumour‐free tissue.

Expression of acute and late-stage inflammatory antigens, c-fms, CSF-1, and human monocytic serine esterase 1, in tumor-associated macrophages of renal cell carcinomas

Purpose: Tumor cells influence the differentiation of infiltrating macrophages. In the present study, the differentiation of macrophages in renal cell carcinomas was investigated with special regard to their possible role in tumor growth and spread. Methods: Macrophages were characterized by means of immunohistochemistry of the Ki-M1P, 25F9, MRP8, MRP14, and MRP8/14 antigens and by means of in situ hybridization of CSF-1, its c-fms-coded corresponding receptor, and human monocytic serine esterase-1 (HMSE-1) mRNA. Macrophage subgroups were quantified within central tumor tissue, the corresponding tumor host interface, and tumor-free tissue and correlated with tumor necrosis, fibrosis, and tumor stage and grade. Results: Macrophage density was much higher within tumor tissue and the tumor/host interface than in tumor-free tissue. Well-differentiated carcinomas showed a lower degree of macrophage density than less-differentiated carcinomas. Tumor-associated macrophages could be divided into an active inflammatory type (MRP14+, MRP8/14+) and into a late-phase inflammatory type (25F9+, MRP8+). Necrosis was seen in less-differentiated carcinomas and associated with a significantly increased density of MRP14+ macrophages, which, however, did not correlate with the extent of necrosis. The density of 25F9+ macrophages was correlated with an extensive connective tissue formation and an advanced tumor stage. c-fms, CSF-1, and HMSE-1 mRNA expression did not discriminate between the macrophage subgroups. Conclusions: Tumor-associated macrophages of the late-stage inflammatory type potentially support the spread of renal cell cancer. CSF-1 derived from tumor cells and macrophages acts as a monocyte attractant and induces macrophage differentiation able to modulate the extracellular matrix rather than to exert cytotoxicity.

Metastasis from renal cell carcinoma to the cervix uteri.

We report on a patient with clear cell adenocarcinoma of the left kidney and a solitary metastasis to the cervix uteri. Metastases from renal cell carcinoma to the female genitalia are uncommon and metastatic involvement of the uterus is very rare. To our knowledge, no more then five cases have been published. A review of the literature is given.

Unusual Bilateral Renal Histiocytosis: Extranodal Variant of Rosai-Dorfman Disease

In 1969 Rosai and Dorfman described a benign pathological entity termed sinus histiocytosis with massive lymphadenopathy mainly at the cervical area associated with fever, leukocytosis and polyclonal hypergammag1obulinemia.l Histopathologically the condition is due to an inflammatory infiltrate of a subtype of S-100 positive histiocytes characterized by hemophagocytosis. Most cases occur during the first and second decades of life. Extranodal manifestation is rare.2 The disease usually resolves spontaneously with low dose corticoid therapy. CASE REPORT

“Falsch-positive” Hodenperfusion bei Hodentorsion in der Power-Doppler-Sonographie

ZusammenfassungWir berichten über einen Patienten mit dem Bild des akuten Skrotums, bei dem die Power-Doppler-Sonographie eine erhaltene arterielle testikuläre Durchblutung zeigte. Bei therapierefraktärem Beschwerdebild erfolgte die verzögerte explorative Hodenfreilegung. Intraoperativ fand sich eine partielle Hodentorsion mit Drehung des Hodens um 180° im Bereich des Rete testis. Dieser Fall zeigt, daß der Nachweis einer arteriellen testikulären Perfusion eine Hodentorsion nicht ausschließt.SummaryWe report about a patient wich acute scrotal pain. Power Doppler sonography demonstrated arterial testicular perfusion. As no amelioration was achieved by conservative treatment, surgical exploration was done after 7 days. Intraoperatively, we found a partial testicular torsion with a 180° rotation of the testis at the rete testis. This case demonstrates, that the detection of intratesticular arterial blood flow cannot exclude testicular torsion.

In vitro investigations of new therapeutic agents on bladder tumor cell lines

In this study sensitivity of human transitional cancer cells to the anticancer agent paclitaxel, an antimicrotubular drug, and to gallium nitrate, a group IIIa metal, was compared. to that of the standard MVAC (methotrexate, vinblastine, doxorubicin and cisplatin) drugs. The reduction of cell proliferation was evaluated after 48 h of incubation of six different cell lines with each agent using the mean transit time (MTT) assay. We investigated both monolayers and spheroids. Paclitaxel showed significantly higher growth inhibitory effects on monolayers than vinblastine, both agents targeting the antimicrotubular apparatus. This could not be reproduced on spheroids, where a survival fraction of 50% was observed even at high concentrations (10 μM). High concentrations of gallium nitrate were needed to achieve sufficient toxicity. These concentrations are beyond the concentration achievable by systemic application. Our findings suggest that paclitaxel may be a clinically useful agent for systemic and intravesical use in bladder cancer.