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S Störkel

Publications and source records attributed to S Störkel.

At least 19 recordsLinked to original sources
PubMed2000

HER-2/neu is expressed in human renal cell carcinoma at heterogeneous levels independently of tumor grading and staging and can be recognized by HLA-A2.1-restricted cytotoxic T lymphocytes.

The HER-2/neu oncoprotein, a 185 kDa membrane-associated tyrosine kinase with extensive homology to the epidermal growth factor receptor (EGF-R), is overexpressed in breast and ovarian carcinomas. Its overexpression is closely associated with poor prognosis in the course of disease. Here we demonstrate HER-2/neu overexpression in both established cell lines and biopsy material obtained from renal epithelial tumors. Immunohistochemical analysis of human kidney tumor lesions using 2 HER-2/neu-specific antibodies revealed HER-2/neu expression in more than 40% of primary epithelial renal tumors and more than 30% of primary renal cell carcinoma (RCC) specimens. A distinctive HER-2/neu expression pattern was found in different subtypes of kidney tumors with the highest frequency in chromophilic and chromophobic RCC, but neither associated with disease stage nor tumor grade. Eight of 10 RCC cell lines expressed significant levels of HER-2/neu mRNA and protein, but at a lower level compared with HER-2/neu overexpressing ovarian carcinoma cells. To evaluate the immune response against HER-2/neu expressing HLA-A2-positive (HLA-A2(+)) RCC cells, allogeneic HLA-A2-restricted cytotoxic T-lymphocyte (CTL) lines generated by pulsing dendritic cells with 3 different HER-2/neu-derived peptides, (HER-2(9.369), HER-2(9.435) and HER-2(9.689), were utilized in chromium-release assays. Specific lysis of HER-2/neu expressing HLA-A2(+) RCC cell lines was mediated by CTL lines specific for each of these 3 HER-2/neu-derived epitopes. The fine specificity of 2 CTL clones was defined to the epitopes HER-2(9.435) and HER-2(9.689). Their specificity was then confirmed by cold target inhibition assays. In addition, CTL-mediated lysis was enhanced by pulsing tumor cells with exogenous HER-2/neu-specific peptides. Our data suggest that (i) HER-2/neu is heterogeneously expressed in different subtypes of RCC, (ii) HER-2/neu is naturally processed by RCC and (iii) HER-2/neu epitopes presented by RCC can be recognized by HLA-A2-restricted, HER-2/neu-specific CTL.

Antigens, Neoplasm↗
PubMed2000

VHL alterations in human clear cell renal cell carcinoma: association with advanced tumor stage and a novel hot spot mutation.

To elucidate the role of somatic alterations for renal cancer etiology and prognosis, we analyzed 227 sporadic renal epithelial tumors for mutations and hypermethylations in the von Hippel-Lindau tumor suppressor gene VHL. Tumors were classified according to the recommendations of the Union Internationale Contre le Cancer (UICC) and the American Joint Committee on Cancer (AJCC). Somatic VHL mutations were identified by PCR, single-strand conformation polymorphism analysis, and sequencing, and hypermethylations were identified by restriction enzyme digestion and Southern blotting. Frequencies of VHL alterations were established, and an association with tumor type or tumor type and tumor stage was evaluated. VHL mutations and hypermethylations were identified in 45% of clear cell renal cell carcinomas (CCRCCs) and occasionally (3 of 28) in papillary (chromophilic) renal cell carcinomas (RCCs). Lack of VHL mutations and hypermethylations in chromophobe RCCs and oncocytomas was statistically significant (P = 0.0001 and P = 0.0004, respectively). RCCs carrying VHL alterations showed, in nine cases (12%), mutations at a hot spot involving a thymine repeat (ATT.TTT) in exon 2. Tumor staging was critical to the VHL mutation/hypermethylation detection rate in CCRCCs shown by separate evaluation of patients from medical centers in Munich, Heidelberg, and Mainz. The spectrum of pT1, pT2, and pT3 CCRCCs and the VHL mutation/hypermethylation detection rate varied among these three groups. Altogether, VHL alterations were significantly associated with pT3 CCRCCs (P = 0.009). This is the first evidence of frequent somatic VHL mutations at a particular site within exon 2 and an association of VHL mutations/hypermethylations with a standard prognostic factor.

Adenoma, Oxyphilic↗
PubMed2000

Interleukin-7 or interleukin-15 enhances survival of Mycobacterium tuberculosis-infected mice.

Both antigen-presenting cells and immune effector cells are required to effectively eradicate or contain Mycobacterium tuberculosis-infected cells. A variety of cytokines are involved to ensure productive "cross talk" between macrophages and T lymphocytes. For instance, infection of macrophages with mycobacteria leads to effective interleukin-7 (IL-7) and IL-15 secretion, and both cytokines are able to maintain strong cellular immune responses of alpha/beta and gamma/delta T cells. Here we show that either cytokine is able to enhance survival of M. tuberculosis-infected BALB/c mice significantly compared to application of IL-2, IL-4, or phosphate-buffered saline (as a control). Enhanced survival could be achieved only when IL-7 or IL-15 was delivered as a treatment (i.e., 3 weeks postinfection), not when it was administered at the time of infection. Increased survival of M. tuberculosis-infected animals was observed following passive transfer of spleen cells harvested from M. tuberculosis-infected, IL-7- or IL-15-treated animals, but not after transfer of spleen cells obtained from mice which received either cytokine alone. Histological examination revealed that IL-7 and IL-15 failed to significantly impact on the number and composition of granulomas formed or the bacterial load. Our data indicated that administration of IL-7 or IL-15 to M. tuberculosis-treated animals resulted in a qualitatively different cellular immune response in spleen cells as reflected by increased tumor necrosis factor alpha and decreased gamma interferon secretion in response to M. tuberculosis-infected antigen-presenting cells.

Adoptive Transfer↗
PubMed1999

Trichloroethylene exposure and specific somatic mutations in patients with renal cell carcinoma.

BACKGROUND: The development of renal cell carcinoma (RCC) has been associated with both genetic and environmental factors-with mutations in the von Hippel-Lindau (VHL) tumor suppressor gene for clear-cell RCC specifically and with long-term exposure to high doses of trichloroethylene (TRI), an industrially important solvent, for RCC generally. We investigated whether TRI exposure produces RCC through a specific mutational effect on the VHL gene by analyzing VHL sequences in the RCCs of patients exposed to high, cumulative doses of TRI. METHODS: The level of exposure for each of 44 patients with RCC who had known industrial exposure to TRI was classified according to the duration, frequency, and mode of exposure. Samples of normal and cancerous tissues were microdissected from paraffin-embedded tissue. DNA was isolated from these samples, and somatic VHL mutations were identified by polymerase chain reaction analysis, single-strand conformation polymorphism analysis, DNA sequencing, and restriction enzyme digestion. Control samples included RCC DNA from 107 patients without known TRI exposure and lymphocyte DNA from 97 healthy subjects. RESULTS: RCCs of TRI-exposed patients showed somatic VHL mutations in 33 (75%) of 44 cases. The mutations were frequently multiple and accompanied by loss of heterozygosity, and there was an association between the number of mutations and the severity of TRI exposure. We observed a specific mutational hot spot at VHL nucleotide 454 in the RCCs of 13 (39%) of the patients, and this mutation was present in adjacent non-neoplastic kidney parenchyma in four of these patients. The nucleotide 454 mutation was neither detected in any of the RCCs from patients without TRI exposure nor in any of the healthy subjects. CONCLUSION: Our results suggest that RCC in patients with high, cumulative TRI exposure is associated with a unique mutation pattern in the VHL gene.

Adolescent↗
PubMed1999

Retraction.

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Retraction Notice↗
PubMed1999

Inverse regulation of vascular endothelial growth factor and VHL tumor suppressor gene in sporadic renal cell carcinomas is correlated with vascular growth: an in vivo study on 29 tumors.

Tumors associated with the VHL (von Hippel-Lindau) disease, such as hemangioblastomas and renal carcinomas and their sporadic counterparts, are cystic and well vascularized. Mutations of the VHL tumor-suppressor gene and elevated levels of vascular endothelial growth factor (VEGF) have been described in these tumors. The upregulation of VEGF has been shown in vitro as a consequence of alteration of the VHL gene. No comprehensive in vivo analysis has yet been carried out of the factors affecting tumor growth, vascularization, VEGF, and VHL expression. We performed immunohistochemistry and mRNA studies on primary sporadic renal carcinomas and matching normal renal tissue. We semiquantitatively analyzed 29 renal carcinomas (22 clear cell, 5 chromophilic, 2 chromophobic tumors) for VHL mRNA, and VEGF expression for morphology and tumor size. Immunohistochemistry was carried out for VEGF protein expression, vascularization, and macrophage infiltration. Vascularization of the chromophilic renal carcinomas was lower than that of the clear cell type of renal carcinoma. Low VEGF protein expression was seen in four of the five chromophilic renal carcinomas. We found two groups of clear cell renal cell carcinoma: one with reduced VHL mRNA and increased VEGF mRNA, and the other without significantly altered VHL or VEGF mRNAs. Tumor vascularization was correlated with VEGF protein and seemed to be independent of macrophage infiltration. Our in vivo findings support the inverse relationship between the regulation of VHL and that of VEGF. Our data also indicate that there may be an VHL-independent pathway for the induction of tumor vascularization.

Adult↗
PubMed1999

[Epithelial tumors of the kidney. Pathological subtyping and cytogenetic correlation].

The recent new morphological classification of epithelial renal tumors has overcome the former unspecified adenoma and carcinoma classification by introducing a specific subtyping. Today we divide in oncocytic and metanephrogenic renal cell adenomas, clear cell-, papillary-, chromophobe-, and collecting duct associated renal cell carcinomas, and transitional cell- and neuroendocrine renal carcinomas. These entities are characterized by a definite immunohistological marker spectrum and differing histogenetic pathways. New cytogenetic data have proven specific chromosomal aberrations for the different tumor types and have confirmed the morphological classification. Certain genetic changes are correlated to specific pathological phenotypes especially in oncocytic tumors. It is possible now to propose an in part hypothetical kidney tumor model which describes the development and progression of adenomas and carcinomas of the kidney in an adenoma-carcinoma sequence.

Carcinoma, Renal Cell↗
PubMed1999

Two new cases of papillary renal cell carcinoma with t(X;1)(p11;q21) in females.

Two cases of papillary renal cell carcinoma (RCC) with a karyotype 46,X,t(X;1)(p11.2;q21) in two female patients aged 9 and 29 years are reported. These observations, and the review of the 17 reported cases with a translocation at band Xp11 confirm that this abnormality delineates a clinicopathological entity within the classical papillary RCC, characterized by the early age of occurrence and, probably, distinct histological features. Including these two new female cases, the sex ratio in cases with t(X;1) appears similar to that observed in the other papillary RCC.

Carcinoma, Papillary↗
PubMed1999

The histology and immunohistochemistry of free buccal mucosa and full-skin grafts after exposure to urine.

OBJECTIVE: To investigate the histological and immunohistochemical behaviour of free buccal mucosa and full-skin grafts after exposure to urine. MATERIALS AND METHODS: A buccal mucosal graft and a full-skin graft were freely transferred into the bladder of 12 minipigs, after stripping the bladder mucosa. Endoscopic investigations were carried out 2 and 5 months after surgery, and the grafts examined after death at 7 months, both histologically and immunohistochemically. RESULTS: Shrinkage of the full-skin graft was apparent endoscopically in five cases. Of the nine full-skin grafts, four showed severe inflammatory reactions, two necrosis and two ulcerations. Conversely, the 10 buccal mucosal grafts had fewer pathological findings (three minimal inflammation and three with scars) and a pronounced similarity on immunohistochemistry. CONCLUSION: The buccal mucosal graft showed significantly fewer adverse histopathological findings after long-term exposure to urine than the full-skin graft and is therefore a preferable material for urethral reconstruction.

Animals↗
PubMed1999

Molecular evidence for derivation of metastatic cells from minor subclones of primary clear renal cell carcinomas.

The production of metastases depends on changes in a large number of genes. It is also connected with the interaction of tumor cells with the environment. It has been reported that primary tumor clone domination is also an important factor in metastasizing, and in many neoplasms dominating clones are the metastatic forerunners. Up to now it is unknown whether domination of a given clone in a primary renal cell carcinoma is a crucial factor in forming metastases or rather presence or absence of specific genes imposes the major advantage in the metastatic process. To study the presence or absence of the duplication and mitotic nondisjunction event as one of the phenomenon in the creation of metastases, as well as possible derivation of metastatic cells from the minor subclone of primary tumor, we examined three metastatic renal clear-cell carcinomas in which by comparative genomic hybridization we detected the loss of 3p in the primary tumor and two copies of 3p in the corresponding metastasis. Loss of heterozygosity analyses using markers for 3p25 (D3S1038), 3p21.1 (D3S1295), and 3p14.2 (D3S1481) proved heterozygosity of at least two 3p loci in all metastatic tumors, which indicates the absence of mitotic nondisjunction event as a cause of occurrence of two copies of 3p in metastases. Our results suggest that in some of the clear-cell renal carcinomas metastatic cells may derive from minor subclones of primary tumors.

Adrenal Gland Neoplasms↗
PubMed1999

Expression of the MRP2 gene-encoded conjugate export pump in human kidney proximal tubules and in renal cell carcinoma.

Human kidney proximal tubule epithelia express the ATP-dependent export pump for anionic conjugates encoded by the MRP2 (cMRP/cMOAT) gene (symbol ABCC2). MRP2, the apical isoform of the multidrug resistance protein, is an integral membrane glycoprotein with a molecular mass of approximately 190 kD that was originally cloned from liver and localized to the canalicular (apical) membrane domain of hepatocytes. In this study, MRP2 was detected in human kidney cortex by reverse transcription-PCR followed by sequencing of a 826-bp cDNA fragment and by immunoblotting using two different antibodies. Human MRP2 was localized to the apical brush-border membrane domain of proximal tubules by double and triple immunofluorescence microscopy including laser scanning microscopy. The expression of MRP2 in renal cell carcinoma was studied by reverse transcription-PCR and immunoblotting in samples from patients undergoing tumor-nephrectomy without prior chemotherapy. Clear-cell carcinomas, originating from the proximal tubule epithelium, expressed MRP2 in 95% (18 of 19) of cases. Immunofluorescence microscopy of MRP2 in clear-cell carcinoma showed a lack of a distinct apical-to-basolateral tumor cell polarity and an additional localization of MRP2 on intracellular membranes. MRP2, the first cloned ATP-dependent export pump for anionic conjugates detected in human kidney, may be involved in renal excretion of various anionic endogenous substances, xenobiotics, and cytotoxic drugs. This conjugate-transporting ATPase encoded by the MRP2 gene has a similar substrate specificity as the multidrug resistance protein MRP1, and may contribute to the multidrug resistance of renal clear-cell carcinomas.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed1998

Heterogeneous expression of the tumor-associated antigens RAGE-1, PRAME, and glycoprotein 75 in human renal cell carcinoma: candidates for T-cell-based immunotherapies?

It has recently been shown that tumor-associated antigens (TAAs) can evoke tumor-specific T-cell-defined immune responses in cancer patients, thereby offering the possibility of treating patients with such antigens. To develop T-cell-based immunotherapeutic approaches for renal cell carcinoma (RCC), we studied the mRNA expression profile of the TAAs RAGE-1, tyrosinase, MAGE-1, MAGE-2, NY-ESO-1, Melan-A/MART-1, glycoprotein (gp) 75, gp100, beta-catenin, PRAME, and MUM-1 in 14 human RCC cell lines and in tissue specimens of 37 primary RCCs, 2 related metastases, and 33 specimens of normal renal epithelium. Reverse transcription-PCR was performed with TAA-reactive primers, and the specificity of the PCR products was confirmed by Southern blot and/or direct sequencing. PRAME (10 of 14 cell lines), RAGE-1 (7 of 14 cell lines), and gp75 (4 of 14 cell lines) antigens were expressed in a high percentage of RCC cell lines, although the level of TAA expression varied among the different RCC cell lines. However, low levels of TAA expression in RCC cells are sufficient for recognition by TAA-specific CTLs. Transcription of tyrosinase, Melan-A/MART-1, MAGE-1, MAGE-2, NY-ESO-1, gp100, beta-catenin, and MUM-1 was not detected in any RCC cell line. Approximately 50% of surgically removed neoplasias expressed at least one TAA. RAGE-1 mRNA expression was found in 8 of 39 (21%) RCC samples, PRAME mRNA expression was found in 15 of 39 (40%) RCC samples, and gp75 mRNA expression was found in 4 of 39 (11%) RCC samples, but the expression levels of these TAAs were heterogeneous in the different RCC lesions. One RCC specimen expressed MAGE-2, whereas transcription was not detected in any RCC specimen for MAGE-1, NY-ESO-1, tyrosinase, Melan-A/MART-1, gp100, beta-catenin, and MUM-1. The normal kidney epithelium samples were negative for any TAA tested. Thus, RAGE-1, PRAME, and gp75 expression is found with a different frequency in surgically removed lesions and in RCC cell lines, suggesting that a subgroup of RCC patients could be selected for immunotherapeutic strategies that may benefit from immunization against the RAGE-1, gp75, and/or PRAME antigens. However, additional targets for T-cell-based immunotherapy of RCC have yet to be identified.

Antigens, Neoplasm↗
PubMed1998

[Retroperitoneal fibrosis and arthritis--a manifestation of the same illness].

Retroperitoneal fibrosis is a disorder in which the retroperitoneal fat is the site of a subacute and chronic inflammatory reaction and is subsequently replaced by dense fibrotic tissue. Rheumatoid nodules are chronic granulomata occurring at sites of pressure and movement, both near the body surface and internally. A 55-year-old sales-manager was admitted to radiation synovectomy after a 5 year history of excessive right and left knee effusions. There were no other clinical or laboratory abnormalities. The patient did not respond to either radioisotope synoviorthesis using radioactive Yttrium (90 Y), or to open synovectomy and prostetic surgery of the right knee. One year later, surgery of left ureter was necessary. Histological findings revealed the diagnosis of Ormond's disease. Comparative histological studies of synovial membrane of knee and retroperitoneal tissues showed local necrosis, fibrin deposition, lining cell proliferation, and infiltration by lymphocytes. Diagnosis of arthritis complicated by retroperitoneal rheumatoid nodules and retroperitoneal fibrosis was made. Serum rheumatoid factor has been negative. For the last 3 years, the patient has been on successful therapy with azathioprine. Rheumatoid nodules of the retroperitoneum have vanished completely and frequency of knee effusions decreased.

Arthritis, Rheumatoid↗
PubMed1998

Familial renal oncocytoma: clinicopathological study of 5 families.

PURPOSE: We analyzed familial renal oncocytoma to provide a foundation for studies aimed at defining genes involved in the pathogenesis of renal oncocytoma. MATERIALS AND METHODS: We describe 5 families with multiple members affected with renal oncocytoma. Tumors were analyzed pathologically, and affected and nonaffected members were screened clinically and genetically. RESULTS: We identified 12 affected male and 3 affected female (ratio 4:1) individuals in the 5 families. In affected family members renal oncocytomas were often multiple and bilateral. No metastatic disease was observed. Most renal oncocytomas were detected incidentally in asymptomatic individuals or during screening of asymptomatic members of renal oncocytoma families. One identical twin pair was affected with bilateral multiple renal oncocytomas. CONCLUSIONS: Renal oncocytoma may be inherited in some families.

Adenoma, Oxyphilic↗
PubMed1998

Chromosome changes in a metastasis of a chromophobe renal cell tumor.

Metastatic disease is a well-known complicating factor in the treatment of renal cell cancer. Whereas radical nephrectomy usually is curative in cases of localized disease, no adequate treatment has been established for metastatic renal tumors. Identification of specific chromosome changes or genes responsible for metastatic behavior may lead to new strategies of treatment in the future. In light of this, we cytogenetically analyzed a metastasis of a chromophobe renal cell carcinoma arising in a 73-year-old male and compared the results with genetic data on primary chromophobe renal tumors. The chromosomal pattern of the present case showed, next to the extensive chromosome losses specific for the chromophobe subtype, structural rearrangements involving chromosomes 1, 5, 12, 15, and 18. Determining whether or not (some of) the observed structural changes are important for the metastatic behavior of chromophobe renal cell tumors will have to await further genetic studies on metastases of renal cancer.

Aged↗
PubMed1997

Loss of heterozygosity studies and deletion mapping identify two putative chromosome 14q tumor suppressor loci in renal oncocytomas.

Renal oncocytoma is considered to be a benign tumor that shares some phenotypic features with chromophobe renal cell carcinoma (RCC). Recently, we described high frequencies of allelic loss at 1p, 2p, 6p, 10p, 13q, 14q, 17p, and 21q, which correlate significantly with the chromophobe subtype of RCC. To investigate the genetic relationship between these two entities, we examined 12 oncocytomas for loss of heterozygosity (LOH) at these regions. In addition, we included markers for 3p, 5q, 7q, 11p, and 22q. The only chromosomal region showing similarly high frequencies of allelic loss for both subtypes was 14q. Therefore, a genetic relationship between renal oncocytoma and chromophobe RCC seems questionable. Eight of 12 oncocytomas (67%) showed LOH at 14q, a frequency that was significantly higher (P < 0.001, chi(2) test) than the frequencies of LOH in all other regions. To define regions potentially harboring novel tumor suppressor genes, we performed multifluorescence microsatellite analysis with 13 markers spanning 14q. Interstitial deletions at different regions of 14q were detected, with the highest frequencies at D14S258 (14q23-24.3) and D14S292 (14q32.1-32.2). 14q LOH might be associated with advanced-stage RCCs or other tumors, but it does not seem to indicate progression in oncocytomas. Its role in pathogenesis of renal oncocytomas remains to be clarified. Here, we provide evidence for two distinct tumor suppressor gene loci at 14q in renal oncocytoma, which will be useful for further fine-mapping studies of these critical regions.

Adenoma, Oxyphilic↗
PubMed1997

Renal oncocytoma with t(5;12;11), der(1)1;8) and add(19): "true" oncocytoma or chromophobe adenoma?

Renal oncocytomas reveal a considerable (cyto)genetic heterogeneity. At least 2 genetic subsets are currently recognized, characterized by (1) translocations involving breakpoint 11q13 and (2) the combined loss of chromosomes 1 and X/Y. We present a case of oncocytoma revealing a 3-way translocation involving breakpoint 11q13, a der(1)t(1;8) and an add(19). The der(1) resulted in loss of chromosome 1 sequences. Using fluorescence in situ hybridization, the 11q13 breakpoint of the present case proved to be slightly different from the one observed previously in 3 cases of renal oncocytoma. Whether the 11q13 breakpoint observed in our case resides in or near another gene remains to be elucidated.

Adenoma, Oxyphilic↗