[Reversible myelofibrosis in angioimmunoblastic lymphadenopathy]

Ankle oedema and abdominal swelling suddenly developed in a 55-year-old woman who also had lymphadenopathy in the neck, axillae and groin. Ultrasonography demonstrated hepatosplenomegaly, ascites and pleural effusions. Histological examination of some lymph-nodes from the axilla and groin revealed angioimmunoblastic lymphadenopathy (low-malignant peripheral T cell lymphoma). Bone-marrow biopsy was undertaken because of a normocytic anaemia (haemoglobin 4.9 g/dl) requiring blood transfusion, thrombocytopenia (5000/microliters) and monoclonal IgG gammopathy. This showed lymphoma-associated secondary myelofibrosis. Treatment with prednisone (2 mg/kg daily for 8 weeks) and vincristine (1 mg/m2 once weekly for 4 weeks) brought about partial remission of the angioimmunoblastic lymphadenopathy with normalization of the clinical and laboratory findings, the splenohepatomegaly regressed, and there was only a small amount of ascites. Four months after onset of the illness bone-marrow biopsy also showed regression of the myelofibrosis.

Cytomorphological, cytogenetic, and molecular biological characterization of four new human renal carcinoma cell lines of the clear cell type

Four new permanent cell lines (RCC-A, -B, -C, and -D) derived from different human renal cell carcinomas of the clear cell type were established in tissue culture. The cell lines displayed characteristic differences in cell size and shape, which allowed individual identification by phase contrast microscopy. Ultrastructurally, the cell lines exhibited varying amounts of cytoplasmatic glycogen and lipid. Immunohistochemistry revealed co-expression of vimentin and cytokeratin in all cell lines. The mean population doubling time ranged from 27 h (RCC-A) to 104 h (RCC-D). RCC-B and -C cells produced slowly growing tumours after heterotransplantation into nude mice, whereas RCC-A and RCC-D cells were non-tumorigenic. The modal chromosome number was either near-diploid (RCC-A, -B, and -C) or near triploid (RCC-D). Clonal abnormalities affecting the short arm of chromosome 3 were seen in all cell lines. Northern blot analysis revealed no expression of the proto-oncogenes c-fos, c-ros, and c-mos, whereas c-Ki-ras expression was observed in all cell lines. Expression of c-myc was observed in RCC-A, RCC-B, and RCC-D cells, whereas c-raf expression could be detected in RCC-B and RCC-D. Tumour suppressor gene p53 mRNA was observed in the cell line RCC-D.

Membranes activate tumor- and virus-specific precursor cytotoxic T lymphocytes in vivo and stimulate tumor-specific T lymphocytes in vitro: implications for vaccination

Plasma membranes contain the entire antigenic repertoire of a cell in the form of processed antigens presented as peptides by major histocompatibility complex (MHC) class I molecules. We report here that plasma membranes but not internal membranes of cognate tumors stimulate murine fibrosarcoma and human melanoma-specific cytotoxic T lymphocyte (CTL) clones in vitro in an antigen-specific. MHC class I-restricted manner. Although stimulation of CTLs by class I-peptide complexes on reconstituted membranes has been documented before, this is the first demonstration of stimulation of cloned CTLs by natural, endogenously processed MHC class I-peptide complexes on plasma membranes. In addition to their ability to stimulate CTLs in vitro, immunization of syngeneic mice with membranes derived from ultraviolet-induced tumor cells, SV40 transformed fibroblasts, or influenza-infected fibroblasts elicits an antigen-specific, MHC class I restricted primary CTL response. To the best of our knowledge, this is also the first demonstration of the ability of cellular membranes to prime an MHC class I-restricted CTL responses in vivo. The ability of membranes to prime a CTL response in vivo suggests that they may be used as T-cell vaccines against tumors or infectious viruses. This approach circumvents the difficulties in generation of human tumor cell lines and identification of CTL-recognized determinants for vaccination and avoids some of the risks associated with whole-cell vaccination such as inoculation of patients with immunosuppressive factors, transforming DNA, or infectious viruses.

[Whipple's disease--a rare cause of secondary amyloidosis]

Two cases of Whipple's disease with secondary amyloidosis are described. One patient had a nephrotic syndrome, the other malabsorption. The chronic inflammatory stimulus of Whipple's disease is discussed as a trigger for the development of secondary amyloidosis. The clinical symptoms of seronegative arthritis, weight loss, chronic diarrhea, intermittent fever and lymphadenopathy may be the clue to the diagnosis of Whipple's disease. Peroral intestinal biopsy is the diagnostic procedure of choice. Adequate antibiotic treatment with a regimen of penicillin and trimethoprim-sulfamethoxazole is indicated and prevents the development of secondary amyloidosis.

Factors influencing survival after resection of pancreatic cancer. A DNA analysis and a histomorphologic study

BACKGROUND

The influence of DNA content on prognosis in stomach cancer has been investigated rarely, and the results are controversial.

METHOD

The prognostic relevance of the DNA content and histomorphologic parameters was evaluated in 41 patients after resection of pancreatic cancer.

RESULTS

In the univariate analysis, the DNA content, tumor size, lymph node status, tumor stage, nuclear grade, and type of resection had a statistically significant influence on the prognosis. No association was found between the DNA content and the histomorphologic features. Apart from the operative procedure, the DNA content was the strongest indicator of prognosis in the multivariate analysis.

CONCLUSIONS

Further investigations are necessary to find out if DNA analysis can be performed preoperatively on material obtained by fine-needle aspiration.

C1q in autoimmune diseases: rheumatoid arthritis

Rheumatoid arthritis is an autoimmune disease involving stimulation of T cells and the production of autoantibodies. In this disease autoantibodies to collagen type II are believed to play a major role in inflammatory events ultimately resulting in joint destruction. However, collagen type II-containing cartilage has been discussed as one of the primary antigens (as evidenced by animal models), despite not being accessible. Evidence is presented here for the involvement of C1q, the collagen-like subunit of the first component of complement, in the pathogenesis of rheumatoid arthritis. The C1q A-chain contains an epitope exhibiting an identical sequence to part of an arthritis modulating epitope from collagen type II. Furthermore, preapplication of a synthetic peptide, representing the epitope on the C1q A-chain, has been shown to delay the onset and reduce the severity of collagen-induced arthritis in a DBA/1 mouse model. Since the complement system, in particular C1q (as part of the first component of the classical pathway), plays a major role in the inflammatory process, we propose that the collagen-like C1q molecule, altered during the inflammatory process, may result in the generation of autoantibodies which also recognize collagen type II, and may thus be considered as a link between the early inflammatory process in the joint and the only later occurring cartilage destruction.

Amyloidoma of the gasserian ganglion as a cause of symptomatic neuralgia of the trigeminal nerve: report of three cases

Three cases of symptomatic neuralgia of the trigeminal nerve due to an amyloidoma in the gasserian ganglion are described. The correct diagnosis was not made prior to histological examination of the surgical biopsy specimens. Medical history and clinical observation led to the diagnosis of a malignant process of the nasal cavities in the first patient; of an inflammatory dental focus in the second patient; and of multiple sclerosis in the third patient. CT findings were normal in cases 1 and 2; in case 3, a schwannoma was suspected from the CT appearances. In case 1, MRI had not been performed; in cases 2 and 3, MRI revealed a tumour mass which was also considered to be a schwannoma. Histologically, the tumours consisted of masses of amyloid deposits which had largely replaced the pre-existing ganglionic cells and satellite cells. Electron microscopy confirmed the fibrillar structure of the deposits. Immunohistochemistry and immunocytochemistry revealed the amyloid to belong to the AL-lambda subtype.

[Malignant pheochromocytoma of the urinary bladder. Case report and review of the literature]

Iatrogenic ureteral lesion is a severe complication in gynecological surgery. We present a case in which the obstruction led to fornix rupture, urine extravasation and urinary ascites. The problematic diagnostic pathway is emphasized.

EGFR and PCNA expression in oral squamous cell carcinomas--a valuable tool in estimating the patient's prognosis

We investigated 100 cases of oral squamous cell carcinomas immunohistologically with respect to the expression of the epidermal growth factor receptor (EGFR) and the proliferating cell nuclear antigen (PCNA). The results were correlated with a new malignancy grading of the invasive tumour areas and the clinical outcome of the patients to estimate the individual prognosis. In conclusion, the amount of antigen expression of both antigens increases with the increasing grade of malignancy of the oral squamous cell carcinoma. Furthermore, there is a statistically significant correlation between the amount of antigen expression and the patient's prognosis. An overexpression of EGFR and PCNA is associated with a short survival of the patient. Both antigens detect relevant tumour biological parameters and are worthy factors in estimating the individual prognosis in patients suffering from oral squamous cell carcinomas.

Cytogenetic analysis of epithelial renal-cell tumors: relationship with a new histopathological classification

Renal-cell carcinomas (RCC) are clinically, histologically and cytogenetically very heterogeneous. The present histological WHO classification shows no clear correlation between histologic subtypes and specific chromosomal abnormalities. In 1986, a new classification was proposed by Thoenes and Störkel based on the cell type from which the tumor arises. They distinguish 5 cell types: clear-cell, chromophilic, chromophobic, ductus Bellini and oncocytic. Results of 105 primary tumors show that, in this new classification, there is a correlation between different subtypes of renal-cell tumor and specific chromosomal abnormalities at a microscopic and/or molecular level. The clear-cell compact type shows structural aberrations of chromosomes I, 3, 4, 5q, 6, 10q, 11q and 12q, together with polysomy of chromosomes X, 4, 5, 7, 10, 12, 15, 16, 19, 20, 21 and 22, monosomy of chromosomes 3, 8, 9, 13, 14, and loss of Y. The main characteristics of the chromophilic tubulo-papillary type are trisomies 7 and 17, and loss of the Y-chromosome. Chromophobic carcinoma seems to be correlated with, inter alia, polysomy 7, trisomies 12, 16, 18, 19, structural abnormalities of 11q, and telomeric associations. Oncocytomas do not reveal any specific chromosomal anomaly, except for trisomy 7. Loss of heterozygosity on 3p is only found in the clear-cell compact type. Some specific chromosomal abnormalities correlate with a particular grade of the tumor. These correlations support the hypothesis that specific chromosomal abnormalities play a role in the histogenesis and oncogenesis of RCC. They may be important for tumor diagnosis and clinical prognosis.

Ultrastructural appearance and cytoskeletal architecture of the clear, chromophilic, and chromophobe types of human renal cell carcinoma in vitro

The clear, chromophilic, and chromophobe types of human renal cell carcinoma have been defined as distinct morphological entities and can be clearly separated by differences of ultrastructural appearance, cytoskeletal architecture, enzyme synthesis, and cytogenetic aberrations. In this report, the cytomorphological aspects of these tumor types are compared in vitro, showing that essential ultrastructural and cytoskeletal characteristics of each tumor type are expressed even after prolonged in vitro cultivation. The pattern of intermediate filament proteins of each tumor type was preserved in vitro, permitting the separation of exclusively cytokeratin-positive chromophobe tumor cells from clear and chromophilic tumor cells with a co-expression of vimentin and cytokeratins. In vitro, the chromophobe tumor cells continued to exhibit abundant cytoplasmatic microvesicles and sparsely distributed "studded" vesicles, which are known to be characteristic features of this tumor type in vivo. This observation confirmed the structural similarity of the chromophobe cell to the 'intercalated cell' of the cortical collecting duct and provided further evidence for the histogenetic derivation of this tumor subtype from the collecting duct system.

Loss of heterozygosity at the short arm of chromosome 3 in renal-cell cancer correlates with the cytological tumour type

A majority of renal-cell tumours retain heterozygosity at the short arm of chromosome 3. To investigate possible histopathological differences between tumours with and without such losses, we compared loss of heterozygosity data from 51 tumours with I histological and 2 different cytological classifications of renal-cell tumour. Using the cytological classification of Thoenes et al., we only found tumours with loss of heterozygosity in these authors' clear-cell category. Possibly, only these tumours arise by a mechanism of double loss of a tumour-suppressor gene on 3p, non-clear-cell renal tumours having a different genetic background. Alternatively, deletions may occur in all subtypes, in which case those subtypes in which no LOH is found may also contain deletions too small to be detected with the set of 3p probes we used. A cytogenetic analysis was carried out on 30 of the tumours. Results of molecular and microscopic cytogenetic analyses did not seem to be in agreement in 12 cases. In 6 of these we found allelic losses in tumours showing morphologically normal copies of chromosome 3. Mitotic recombination or loss of one chromosome 3 homologue followed by duplication of the remaining homologue is a likely explanation. The other 6 cases showed microscopic abnormalities of chromosome 3 which were not reflected, or only partly reflected, as allelic losses. These discrepancies are caused either by the limitations of microscopic analysis in exactly determining a breakpoint or tracing a translocated part of a chromosome, or by the failure of molecular analysis to demonstrate LOH if this occurs in only a minority of cells.

Autosomal dominant polycystic kidney disease--in vitro culture of cyst-lining epithelial cells

The major form of autosomal dominant polycystic kidney disease (ADPKD) in humans is linked to the PKD1 gene on chromosome 16p. The identity of the gene and the underlying pathogenetic mechanisms are not yet defined. Cyst-lining epithelial cells derived from a polycystic kidney were successfully grown in culture and designated MZ-PKD-1 cells. By linkage analysis, the related pedigree of the nephrectomized patient could be linked to the PKD1 gene on chromosome 16p. Thus, these cells exhibit the genotype of a mutated PKD1 gene and represent an in vitro culture model for ADPKD involving chromosome 16p. The antigenic phenotype was characterized immunohistologically by epithelial differentiation antigens and markers of individual nephron segments. An essentially identical antigenic pattern of proximal tubular cells was observed both in vitro and in fresh frozen tissue. Electron microscopy showed the formation of a microvillous-like coating. During growth phases in vitro successive changes in the cell shape were observed. MZ-PKD-1 cells exhibited a limited lifespan ending in replicative senescence. Northern blot analysis of kidney-growth-related genes, c-myc, TGF-alpha, TGF-beta 1, and EGF receptor revealed abundant expression of all of these genes in MZ-PKD-1 cells.

[Primary pulmonary nodular amyloidosis and multiple emphysematous bullae in Sjögren syndrome]

The authors report on a very rare case of an isolated primary nodular pulmonary amyloidosis with multiple emphysematous bullae in Sjögren's syndrome. The circular foci present in both lungs in disseminated form were immunohistochemically speaking amyloid deposits of the AL-lambda type. There were no pointers to other organ manifestations or monoclonal immunoglobulins in the serum and/or urine.

Carbohydrate metabolism in human renal clear cell carcinomas

BACKGROUND

Renal cell carcinomas can be subclassified into clear cell carcinomas, chromophobe cell carcinomas, chromophilic cell carcinomas, and oncocytomas. Previous studies, in which no distinction among the different types of renal cell tumors and their grades of malignancy was performed, showed that these tumors had high glycolytic rates.

EXPERIMENTAL DESIGN

The carbohydrate metabolism of control human kidney samples and renal clear cell carcinomas with different degrees of cytologic malignancy (G I, G II, and G III) was studied by determining the glycogen and glucose-6-phosphate levels and the activities of key enzymes involved in glycolysis (hexokinase, glucokinase, pyruvate kinase), gluconeogenesis (glucose-6-phosphatase, fructose-1,6-diphosphatase), and the pentose phosphate pathway (glucose-6-phosphate dehydrogenase) in these tissues and compared with those of a limited number of chromophilic cell carcinomas, chromophobe cell carcinomas, and oncocytomas.

RESULTS

The glycogen and glucose-6-phosphate levels were significantly higher in G I, G II, and G III clear cut carcinomas than in control kidneys; glucokinase, hexokinase, and glucose-6-phosphate dehydrogenase activities remained unchanged, pyruvate kinase activity was enhanced, and glucose-6-phosphatase as well as fructose-1,6-diphosphatase activities were strongly reduced when compared with control kidney values. In chromophilic cell carcinomas glycogen content, glucose-6-phosphate dehydrogenase, and pyruvate kinase activities were elevated, while fructose-1,6-diphosphatase activity was reduced. In chromophobe cell carcinomas glycogen content was elevated and gluconeogenesis was reduced, whereas glycolysis was not activated. In oncocytomas glycogen was not detected and glucose-6-phosphate dehydrogenase, pyruvate kinase, and fructose-1,6-diphosphatase activities remained unchanged.

CONCLUSIONS

It has been demonstrated that a series of characteristic changes occur in the carbohydrate metabolism of renal clear cell carcinomas: glycogen and glucose-6-phosphate levels increase, glycolysis is activated, and gluconeogenesis is reduced. Furthermore, the alterations of the carbohydrate metabolism within clear cell carcinomas are clearly distinct from those observed in chromophilic cell carcinomas, chromophobe cell carcinomas, and oncocytomas.

[Image analysis of DNA cytometry in tumors of the upper gastrointestinal tract]

The prognostic influence on the DNA content was investigated in 189 patients (esophagus carcinoma n = 45, gastric cancer n = 103, pancreatic cancer n = 41) who underwent a curative resection. In a multivariate analysis the DNA content had a strong as well as an independent influence on the prognosis in esophagus cancer and in pancreatic carcinoma. In gastric cancer, the DNA content had no influence on the prognosis. These results show that the DNA content of the tumor cells, as a measurement of the numerous chromosomal aberrations, well reflects the aggressiveness of the tumor growth in esophagus- and pancreatic cancer. In these tumors it represents the decisive criteria for the prognostic judgement.

Modulation of type II collagen-induced arthritis in DBA/1 mice by intravenous application of a peptide from the C1q-A chain

In this report we are able to show that intravenous (i.v.) application (day 0) of a nonapeptide (residues 26-34) from the human C1q A-chain (designated peptide A-C1q) prior to intradermal (i.d.) administration of chicken type II collagen (CII) in arthritis-susceptible DBA/1 mice (H2q), leads to abrogation of polymorphonuclear neutrophil (PMN) invasion into the joints. This nonapeptide exhibits epitope characteristics and high homology to residues 137-147 of CB11 (a cyanogen bromide fragment of chicken CII, known to contain both arthritis inducing and suppressing determinants). Arthritis index was lowest in animals pretreated i.v. with CII (as internal control), though animals pretreated i.v. with peptide K (residues 137-147 with an additional glycine residue from CB11) or peptide A-C1q exhibited comparative arthritic indices. Only in the arthritis-positive control group (day 0: PBS i.v.) did i.d. application of CII lead to invasion of PMN into the synovial layer and the joint space. Analysis of antibody (Ab) responses at day 48 after i.v. immunization (day 0) and CII challenge (day 7) revealed IgE-Abs to native CII and also to native C1q. IgG titers to CII were highest in animals pretreated with peptide A-C1q. Abs from this group, exhibiting activity to peptide A-C1q (immunizing antigen), were of mainly IgG1 and IgG3 isotypes. Evaluation of the immune response following i.v. application of peptide A-C1q or CII, prior to i.d. CII administration, in DBA/1 mice, revealed IgM responses to peptide A-C1q and peptide K, but not to CII. Intravenous application of peptide A-C1q led to generation of IgG3-Abs reacting only with peptide A-C1q and peptide K, but not with native CII. Additionally, i.v. application of peptide A-C1q elicited IgG responses to a pentapeptide, resembling amino acid residues 26-30 (K-G-E-Q-G) of the C1q A-chain. This five residue antigenic determinant is present in peptide K, in chicken and human CII as well as in human C1q. No specific IgE response to any of the antigens tested could be detected. Since a peptide from the C1q A-chain is both capable of eliciting immune responses and modulating CII-induced arthritis in mice, we postulate that the collagen-like complement component C1q is involved in the development of CII-induced inflammatory arthritic lesions, and may represent, in vivo, the early antigen responsible for inducing anticollagen antibodies prior to CII in hyaline cartilage becoming available as antigen.

The role of osteonectin in human tooth development: an immunohistological study

We investigated immunohistologically 160 teeth and dental germs in various stages of tooth development taken from human individuals (13th week of pregnancy to the 24th year of life) to study the osteonectin expression in dental hard tissue. In the course of dentinogenesis, the predentin, the odontoblasts, and their cell processes show a positive osteonectin staining reaction. During cementogenesis, osteonectin is synthesized by cement-producing fibroblasts, cementoblasts, and cementocytes. The expression of osteonectin during dentinogenesis and cementogenesis is closely related to the development of the respective calcified tissue. All cells of the inner and outer enamel epithelium, the cells of the stratum reticulare and stratum intermedium, the ameloblasts, and the enamel substance are osteonectin negative, just as dentin and cement are. The results of this study indicate one important physiological role of osteonectin as a protein associated with the formation of collagen containing mineralizing tissues like human bone, as well as human dentin and cement.

Purification and characterization of a Salmonella typhimurium agglutinin from gut mucus secretions

One of the earliest events in Salmonella typhimurium pathogenesis seems to be the interaction of the bacterium with the mucus of the gut. After exposing S. typhimurium to guinea-pig colon, we were able to demonstrate by electron microscopy that S. typhimurium bacteria were trapped on, or in, the mucus layer. Specific components isolated from crude mucus secretions were found to aggregate the bacteria. The degree of bacterial aggregation was dependent on the protein concentration of the crude mucus and on time. Aggregation of S. typhimurium could be abolished by sugars: L-fucose exhibited the strongest inhibition, followed by D-glucose, D-galactose and D-mannose. Lectins were also capable of inhibiting aggregation, the lectin of Ulex europaeus (UEA I), specific for L-fucose, was found to be a stronger inhibitor of bacterial aggregation than Con A. The agglutinin for S. typhimurium isolated from guinea-pig colonic crude mucus preparation was characterized as a 15 kDa glycoprotein. An affinity-purified anti-15 kD antibody inhibited, dose-dependently, the aggregation of S. typhimurium by crude mucus material.

[Results of studies of surgically treated carpal tunnel syndrome with obligate tenosynovectomy of the flexor tendons]

The authors present a follow-up of thirty five patients with carpal tunnel syndrome, who had undergone surgical treatment including synovialectomy of the flexor tendons. Beyond the clinical findings, pre- and postoperative comparison of the electromyograms, conduction velocities and an exact analysis of the lipid disorders were studied. These findings and the results of the histological analysis of the tenosynovial membrane are evaluated with special regard to the etiology of the carpal tunnel syndrome.

Reaction patterns of tumor infiltrating lymphocytes in different renal cell carcinomas and oncocytomas

1. Only clear cell and chromophilic carcinomas of the kidney exhibit a considerable lymphocytic infiltration which is compatible with some immunological responsiveness. Chromophobic carcinomas and benign oncocytomas seem to be immunologically reactive. This reflects the different antigen spectrum and histogenesis of these tumors (Störkel and Jacobi, 1989). Clear cell and chromophilic carcinomas are derived from the proximal tubule and chromophobic carcinomas and oncocytomas from the collecting duct. 2. The tumor periphery seems to be the place of greatest immunological importance, as basic requirements of a sufficient lymphocyte/tumor cell interaction can only be expected there. If these data are taken into account for a therapeutical approach with biological immune modifiers the size of the tumor (tumor burden) and proliferation index must be considered too. This might be a likely explanation for the positive effect of inhaled interleukin-2 on lung metastasis in renal cell cancers. Harvesting of tumor infiltrating lymphocytes for therapeutical purposes should take these findings into account. 3. In spite of dense lymphocytic infiltration only 3% of the tumor infiltrating lymphocytes exhibit the activation marker CD 25. There seems to be a sufficient T cell locomotion in renal cell carcinomas but an insufficient T-cell activation. Whether this fact is induced by lacking cytokine stimulation of involved lymphocytes or by still unknown mediators of the tumor cells is not yet known and needs further investigation. 4. Clear cell carcinomas exhibit most adhesion molecules and the highest amount of infiltrating cytotoxic T-cells and natural killer cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of differentiation antigens and growth-related genes in normal kidney, autosomal dominant polycystic kidney disease, and renal cell carcinoma

Cellular differentiation and mRNA levels of genes involved in kidney growth were investigated in normal kidney cells, cyst-lining epithelial cells of polycystic kidney disease, and renal carcinoma cells (RCC). All cells comparatively studied exhibited an antigenic phenotype of proximal tubular cells as shown by the expression of a panel of brush border membrane enzymes and kidney-associated cell surface antigens. The epithelial developmental antigen Exo-1 was expressed in 50% to 80% of cyst-lining epithelia in polycystic kidney tissue and in 20% to 30% of polycystic kidney cells cultured in vitro. Normal kidney cells and RCC were negative under identical culture conditions. The expression of antigen Exo-1 is associated with hyperproliferation in an epithelial tissue compartment composed of cells which have not yet reached their terminal differentiation state. Increased amounts of mRNA of the growth factor receptor system of epidermal growth factor (EGF) receptor and its ligand transforming growth factor (TGF)-alpha were associated with the malignant phenotype of RCC. Increased expression of EGF receptor and TGF-alpha, although less prominent, were also observed in polycystic kidney cells compared with normal kidney cells. In conclusion, the expression of Exo-1 in cyst-lining epithelial cells of autosomal dominant polycystic kidney disease (ADPKD) and the altered regulation of TGF-alpha and EGF receptor in these cells contribute to the hypothesis that hyperproliferation is an underlying pathogenic mechanism of ADPKD.

Characterization of conservatively resected renal tumors using automated image analysis DNA cytometry

The DNA histograms of 57 conservatively resected renal tumors were studied using automated image analysis DNA cytometry (Leytas II). Forty-nine of the analyzed tumors were renal cell carcinomas, six were oncocytomas, one was an angiomyolipoma, and one was a renal cell adenoma. On the basis of their DNA histograms, diploid, tetraploid, and aneuploid tumors could be distinguished. Aneuploid tumors could be subtyped further according to the DNA content of the stem cell line as hyperdiploid, hypertriploid, or hypertetraploid. Eight of the tumors were characterized by a combination of diploid and hypertriploid stem cell lines. During a mean follow-up of 5 years, only the two patients with a pure hypertriploid tumor died of distant metastases. These results indicate that automated DNA image analysis cytometry is able to differentiate among several types of renal tumors with obviously different prognoses.