McClellan Walther

National Institutes of Health, Bethesda, MD, USA

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Publications (9)93.37 Total impact

  • Article: Expression of hypoxia inducible factor-1alpha and 2alpha in genetically distinct early renal cortical tumors.
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    ABSTRACT: The role of the HIF class of transcription factors has been implicated to be a critical step in clear cell kidney tumorigenesis. To assess if HIF over expression is a prominent feature of other renal cell carcinoma histological subtypes we characterized the expression of HIF-1alpha and HIF-2alpha in genetically distinct early renal cortical tumors. Nascent renal tumors of distinct histology from patients with a hereditary renal tumor syndrome were characterized for HIF expression using high amplification immunohistochemistry. In addition, indirect immunofluorescence and confocal microscopy were used for subcellular localization of HIF-1alpha and 2alpha in clear cell renal carcinoma cells. Clear cell RCC tumors from patients with von Hippel-Lindau disease strongly expressed HIF-1alpha and HIF-2alpha (10 of 12 and 12 of 12 tumors, respectively). Chromophobe tumors from patients with Birt-Hogg-Dubé syndrome expressed predominantly HIF-2alpha with weaker HIF-1alpha expression (12 of 12 and 6 of 12 tumors, respectively). Consistent HIF-1alpha expression was not seen in type I papillary tumors from patients with hereditary papillary renal carcinoma (3 of 12 tumors). However, half of the type I papillary tumors (6 of 12) expressed HIF-2alpha. Differential patterns of HIF-1alpha and HIF-2alpha protein over expression were found among the 3 human kidney tumor types associated with multifocal hereditary kidney tumor syndromes. Consistent, simultaneous over expression of HIF-1alpha and HIF-2alpha appears to be specific to VHL negative clear cell renal cell carcinoma. Consistent HIF-2alpha expression was found in all 3 renal cortical tumor subtypes, suggesting a pivotal role in renal cortical tumorigenesis. Differential function of HIF-1alpha vs HIF-2alpha is suggested by the distinct subcellular localization pattern of HIF-1alpha and HIF-2alpha in clear cell renal carcinoma cells.
    The Journal of Urology 06/2006; 175(5):1908-14. · 3.75 Impact Factor
  • Article: Response of papillary renal cell carcinoma in a solitary kidney to high dose interleukin therapy.
    Eric K Diner, Marston Linehan, McClellan Walther
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    ABSTRACT: Kidney cancer affects 36 000 Americans annually and is responsible for nearly 12 000 deaths every year in the US. Treatment with interleukin-2 (IL-2), the only FDA approved therapy for patients with advanced kidney cancer, is associated with a 10% complete response and a 12% partial response. To date, clear cell renal carcinoma has been the only histological type associated with response to IL-2-based therapy. In the current report, we describe a response to IL-2 therapy in a patient with type I papillary renal carcinoma.
    International Journal of Urology 12/2005; 12(11):996-7. · 1.75 Impact Factor
  • Article: Hereditary leiomyomatosis associated with bilateral, massive, macronodular adrenocortical disease and atypical cushing syndrome: a clinical and molecular genetic investigation.
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    ABSTRACT: Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant disorder caused by mutations in the fumarate hydratase (FH) gene on chromosome 1q42.3-43. Massive macronodular adrenocortical disease (MMAD) is a heterogeneous condition associated with Cushing syndrome (CS) and bilateral hyperplasia of the adrenal glands. In MMAD, cortisol secretion is often mediated by ectopic, adrenocortical expression of receptors for a variety of substances; however, to date, no consistent genetic defects have been identified. In a patient with HLRCC caused by a germline-inactivating FH mutation, we diagnosed atypical (subclinical) CS due to bilateral, ACTH-independent adrenocortical hyperplasia. A clinical protocol for the detection of ectopic expression of various hormone receptors was employed. Histology was consistent with MMAD. The tumor tissue harbored the germline FH mutation and demonstrated allelic losses of the 1q42.3-43 FH locus. We then searched the National Institutes of Health (NIH) databases of patients with MMAD or HLRCC and found at least three other cases with MMAD that had a history of tumors that could be part of HLRCC; among patients with HLRCC, there were several with some adrenal nodularity noted on computed tomography but none with imaging findings consistent with MMAD. From two of the three MMAD patients, adrenocortical tumor DNA was available and sequenced for coding FH mutations; there were none. We conclude that in a patient with HLRCC, adrenal hyperplasia and CS were due to MMAD. The latter was likely due to the FH germline mutation because in tumor cells, only the mutant allele was retained. However, other patients with MMAD and HLRCC, or HLRCC patients with adrenal imaging findings consistent with MMAD, or MMAD patients with somatic FH mutations were not found among the NIH series. Although a fortuitous association cannot be excluded, HLRCC may be added to the short list of monogenic disorders that have been reported to be associated with the development of adrenal tumors; FH may be considered a candidate gene for MMAD.
    Journal of Clinical Endocrinology &amp Metabolism 07/2005; 90(6):3773-9. · 6.50 Impact Factor
  • Article: Metastatic renal cell carcinoma versus pancreatic neuroendocrine tumor in von Hippel-Lindau disease: treatment with interleukin-2.
    Christopher Williams, McClellan Walther
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    ABSTRACT: Differentiating between clear cell neuroendocrine tumor (NET) of the pancreas and renal cell carcinoma (RCC) metastatic to the pancreas can be challenging in patients with von Hippel-Lindau disease (VHL). The clear cell features of both NET and RCC in VHL patients may lead to misdiagnosis, inaccurate staging, and alternative treatment. We present a patient in which this occurred. As clear cell NETs closely resembling metastatic RCC are distinctive neoplasms of VHL and metastatic RCC to the pancreas in the VHL population is rare, careful pathologic examination should be performed prior to subjecting patients to definitive surgical or medical therapies.
    TheScientificWorldJOURNAL 02/2005; 5:9-10. · 1.66 Impact Factor
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    Article: von Hippel-Lindau disease.
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    ABSTRACT: von Hippel-Lindau disease is a heritable multisystem cancer syndrome that is associated with a germline mutation of the VHL tumour suppressor gene on the short arm of chromosome 3. This disorder is not rare (about one in 36000 livebirths) and is inherited as a highly penetrant autosomal dominant trait (ie, with a high individual risk of disease). Affected individuals are at risk of developing various benign and malignant tumours of the central nervous system, kidneys, adrenal glands, pancreas, and reproductive adnexal organs. Because of the complexities associated with management of the various types of tumours in this disease, treatment is multidisciplinary. We present an overview of the clinical aspects, management, and treatment options for von Hippel-Lindau disease.
    The Lancet 07/2003; 361(9374):2059-67. · 38.28 Impact Factor
  • Article: Mutations in a novel gene lead to kidney tumors, lung wall defects, and benign tumors of the hair follicle in patients with the Birt-Hogg-Dubé syndrome.
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    ABSTRACT: Birt-Hogg-Dubé (BHD) syndrome is a rare inherited genodermatosis characterized by hair follicle hamartomas, kidney tumors, and spontaneous pneumothorax. Recombination mapping in BHD families delineated the susceptibility locus to 700 kb on chromosome 17p11.2. Protein-truncating mutations were identified in a novel candidate gene in a panel of BHD families, with a 44% frequency of insertion/deletion mutations within a hypermutable C(8) tract. Tissue expression of the 3.8 kb transcript was widespread, including kidney, lung, and skin. The full-length BHD sequence predicted a novel protein, folliculin, that was highly conserved across species. Discovery of disease-causing mutations in BHD, a novel kidney cancer gene associated with renal oncocytoma or chromophobe renal cancer, will contribute to understanding the role of folliculin in pathways common to skin, lung, and kidney development.
    Cancer Cell 09/2002; 2(2):157-64. · 26.57 Impact Factor
  • Article: Risk of renal and colonic neoplasms and spontaneous pneumothorax in the Birt-Hogg-Dubé syndrome.
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    ABSTRACT: The Birt-Hogg-Dubé syndrome, a genodermatosis characterized by benign tumors of the hair follicle, has been associated with renal and colonic neoplasms and spontaneous pneumothorax, but the risk of developing these disorders is unknown. We identified risk factors for renal tumors and spontaneous pneumothorax in 98 patients affected with the Birt-Hogg-Dubé syndrome, in 13 Birt-Hogg-Dubé haplotype carriers, and in 112 unaffected family members. Development of renal tumors was strongly associated with the Birt-Hogg-Dubé syndrome and age. The odds ratio for renal tumor in BHD-affected family members adjusted for age was 6.9 (95% confidence interval, 1.5-31.6) and approximately 9.0 for the other risk factors considered. Chromophobe renal carcinoma, an uncommon type of renal cancer, was the predominant type of renal cancer found. Spontaneous pneumothorax was also strongly associated with the Birt-Hogg-Dubé syndrome and age. The odds ratio for pneumothorax in BHD-affected individuals, adjusted for age, was 50.3 (95% confidence interval, 6.4-392), and about 32 times higher adjusting for the other risk variables. Colon cancer and colon polyps were not related to the Birt-Hogg-Dubé syndrome. The Birt-Hogg-Dubé syndrome confers an increased risk for the development of renal tumors and spontaneous pneumothorax. We found no increase in risk for the development of colon polyps or colon carcinomas.
    Cancer Epidemiology Biomarkers &amp Prevention 05/2002; 11(4):393-400. · 4.12 Impact Factor
  • Article: Improved detection of germline mutations in the von Hippel‐Lindau disease tumor suppressor gene
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    ABSTRACT: von Hippel-Lindau disease (VHL) is an inherited neoplastic disorder characterized by the development of tumors in the eyes, brain, spinal cord, inner ear, adrenal gland, pancreas, kidney, and epididymis. The VHL tumor suppressor gene was identified in 1993. Initial studies reported the detection of germline mutations in the VHL gene in 39–75% of VHL families. We used tests that detect different types of mutations to improve the frequency of detection of germline mutations in VHL families. The methods included quantitative Southern blotting to detect deletions of the entire VHL gene, Southern blotting to detect gene rearrangements, fluorescence in situ hybridization (FISH) to confirm deletions, and complete sequencing of the gene. Here we report that we have detected germline mutations in the VHL gene in 100% (93/93) of VHL families tested. In addition, we describe 13 novel intragenic VHL germline mutations. With the methodology described in this article, it is now possible to identify germline mutations in virtually all families with VHL. Hum Mutat 12:417–423, 1998. © 1998 Wiley-Liss, Inc.
    Human Mutation 12/1997; 12(6):417 - 423. · 5.69 Impact Factor
  • Article: Von Hippel-Lindau (VHL) disease: distinct phenotypes suggest more than one mutant allele at the VHL locus
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    ABSTRACT: As part of an attempt to locate the von Hippel-Lindau locus (VHL) on chromosome 3, we evaluated 41 families with von Hippel-Lindau disease from the United States and Canada. One large family was identified whose disease phenotype was distinct from typical VHL. The most common disease manifestation was pheochromocytoma occuring in 57% (27/47) of affected family members. Few (4/47) affected family members had symptomatic spinal or cerebellar hemangioblastomas; no affected family member had renal cell carcinoma (0/47) or pancreatic cysts (0/24). Previously, genetic analysis demonstrated that the disease manifestations in this family were linked to RAF1 and D3S18, markers shown to be linked to typical VHL. These results suggest that there are mutant alleles at the VHL locus associated with distinct tissue specificities.
    Human Genetics 05/1991; 87(2):207-210. · 5.07 Impact Factor

Institutions

  • 2006
    • National Institutes of Health
      • Center for Cancer Research
      Bethesda, MD, USA
  • 1997–2005
    • National Cancer Institute (USA)
      • • Center for Cancer Research
      • • Laboratory of Tumor Immunology and Biology
      • • Urologic Oncology Branch
      Bethesda, MD, USA