3p involvement in a renal cell carcinoma in von Hippel-Lindau syndrome. Region of tumor breakpoint clustering on 3p?

A constitutional balanced t(3;8)(p14;q24.1) translocation results in disruption of the TRC8 gene and predisposition to clear cell renal cell carcinoma

Studying the molecular basis of familial renal cell carcinoma (RCC) has allowed identification of novel RCC genes involved in the pathogenesis of both inherited and sporadic RCC. We describe a constitutional balanced t(3;8)(p14;q24.1) translocation found in a brother and sister with bilateral clear cell RCC (CC-RCC) diagnosed in their forties. Consistent with a prior report, we demonstrated by RT-PCR of RNA from lymphoblastoid cells fusion mRNAs derived from the fragile histidine triad (FHIT) at 3p14 and TRC8 at 8q24.1 in both affected siblings. Cytogenetic analysis of a CC-RCC tumor from the affected sister from short-term tumor cell culture showed both diploid and pseudotetraploid populations containing the translocation and normal appearing chromosomes 3 and 8. Fluorescent in situ hybridization using bacterial artificial chromosomes containing sequences from the FHIT and TRC8 genes demonstrated normal FHIT signals and TRC8 signals on nontranslocated chromosomes in the constitutional blood sample, but the TRC8 signal was absent in a subset of diploid and pseudotetraploid cells from the tumor. The tumor also contained a heterozygous VHL frameshift somatic mutation. These results confirm that balanced translocations disrupting the TRC8 and FHIT genes result in an increased genetic susceptibility for bilateral CC-RCC. The presence of diploid and tetraploid tumor cells with and without TRC8 deletions on the nontranslocated chromosome suggest that loss of the remaining normal allele of TRC8 may contribute to tumor development at later stages.

Renal cancer: cytogenetic and molecular genetic aspects

To date, much progress has been made in the fields of cytogenetics and molecular genetics of renal tumors. The previous and recent findings have delineated the characteristics of the various tumors, particularly the cytogenetic and molecular differences that exist between papillary and nonpapillary clear cell renal cell carcinomas (RCCs). At the same time, new cytogenetic subtypes have emerged [e.g., t(X;1)] in subtypes of RCC, while in others (e.g., Wilms tumors) several new cytogenetic abnormalities and consequent molecular involvement have been found. In addition to Wilms tumor, papillary RCC, and clear-cell RCC, cytogenetic and fluorescence in situ hybridization analyses have been performed on several other tumors of the kidney, including chromophobic carcinoma, metanephric adenoma, collecting duct carcinoma, transitional cell carcinoma, congenital mesoblastic nephroma, and malignant rhabdoid tumors of the kidney. This review is therefore intended to present a concise update on the cytogenetic and molecular data on renal tumors, focusing mainly on the clinical usefulness of the findings reported in the literature.

Hemangioblastoma of the posterior fossa. The role of multimodality treatment

The authors made a review of a series of patients with hemangioblastomas of the posterior fossa treated between 1973 and 1993. A total of 32 patients were analyzed with 24 patients receiving resection, 8 patients receiving radiosurgery and 2 patients receiving conventional radiotherapy. The mortality in the patients with a resection was considered acceptable with 2 deaths (8%) and with a morbidity of 3 patients (12.5%). A review of the literature suggests that conventional radiotherapy with high doses (45-60 Gy) may have a role in the post-operative control of hemangioblastomas and in some cases could be employed even before the resection in order to facilitate the surgery. The radiosurgical treatment is regarded like adjuvant. Poor results were obtained with radiosurgery in large tumors where low doses (less than 20 Gy) were used. Because of the rarity and complexity of these tumors, mainly when associated with von Hippel-Lindau disease, a multicenter study could be useful with the assessment of the optimal utilization and combination of these treatment modalities.

The von Hippel-Lindau tumor suppressor gene. A rare and intriguing disease opening new insight into basic mechanisms of carcinogenesis

The von Hippel-Lindau (VHL) disease is an inherited tumor susceptibility syndrome featuring a high variety of benign and malignant tumors. The gene has been localized and cloned at 3p25-26. Recent functional analysis defined the VHL gene product as an inhibitor of the transcription elongation process. Its possible involvement in the vascularization process may explain the histologic features of VHL tumors providing insight into basic mechanism of tumorigenesis. Direct genetic testing is available for patients affected with VHL. Seventy to eighty percent of the germline mutations expected could be detected. As first geno/phenotype correlations have been established, we are now beginning to understand the diversity of this fascinating disease at the molecular level. As mutational analysis proved to be of striking prognostic significance, gene testing became an important tool for the management of the disease. The VHL gene was also found to be responsible for tumorigenesis in the corresponding sporadic tumors, especially in the clear cell type of renal cell carcinomas. The understanding of the normal and disturbed function of the VHL gene product will enable us to develop treatment strategies based on and targeted at the molecular cause of the disease. In this review we summarize the current knowledge about genetics, clinics, and function of VHL.

Detection of a germline mutation and somatic homozygous loss of the von Hippel-Lindau tumor-suppressor gene in a family with a de novo mutation. A combined genetic study, including cytogenetics, PCR/SSCP, FISH, and CGH

von Hippel-Lindau (VHL) disease is a pleiotropic disorder featuring a variety of malignant and benign tumors of the eye, central nervous system, kidney, and adrenal gland. Recently the VHL gene has been identified in the chromosomal region 3p25-26. Prognosis and successful management of VHL patients and their descendants depend on unambiguous diagnosis. Due to recurrent hemangioblastomas, a29-year-old patient without familial history of VHL disease was diagnosed to be at risk for the disease. Histopathological examination of a small renal mass identified a clear cell tumor with a G1 grading. Genetic characterization of the germline and of the renal tumor was performed. Polymerase chain reaction/single strand conformation polymorphism (PCR/SSCP) analysis with primers from the VHL gene identified a deletion of a single nucleotide in exon 2 in the patient's germline and in the tumor, but not in the DNA of his parents. This deletion therefore must be a de novo mutation. Comparative genome hybridization (CGH) and fluorescence in situ hybridization (FISH) analysis of the G1 tumor with differentially labelled yeast artifical chromosome (YAC) clones showed loss of 3p and of the 3p26 signals, respectively. In conclusion, we identified a de novo germline mutation in the VHL gene of a young patient and a somatic chromosome 3p loss at the homologous chromosome 3 in his renal tumor. Our results suggest a recessive mode of inactivation of the VHL gene, providing solid evidence for its tumor-suppressor gene characteristics. Our data show the diagnostic potential of genetic testing, especially in patients without VHL family history. Furthermore, the findings of homozygous inactivation of the VHL gene in a G1 tumor support the notion that the inactivation of the VHL gene is an early event in tumorigenesis of renal cell carcinoma.

Cytogenetic and fluorescence in situ hybridization studies on sporadic and hereditary tumors associated with von Hippel-Lindau syndrome (VHL)

We performed cytogenetic and fluorescence in situ hybridization (FISH) studies on 29 sporadic or familial tumors associated with von Hippel-Lindau [correction of Landau] disease. Four of five renal cell carcinomas with detectable alterations showed clones with chromosome 3 alterations. These changes led to loss of genetic material visible with cytogenetic resolution: either an unbalanced translocation involving 3p or loss of a whole homolog 3, resulting in monosomy of 3p. We have previously mapped the VHL gene to chromosomal region 3p25-p26. We applied FISH using the single copy probes cA233 and cA479, sequences close to the VHL gene, in a search for submicroscopic deletions of 3p. Use of FISH with differentially labeled probes indicated cA479 to be distal to cA233, but both were located within bands 3p25-26. FISH with single copy probes for interphase cytogenetics detected four subclones with deletions in the VHL region in 8/22 tumors, including four tumors which appeared cytogenetically normal. FISH proved to be a powerful tool in tumor genetic studies, especially helpful in detecting tumor subclones in benign and slowly growing tumors.

Cytogenetic and molecular studies of a familial renal cell carcinoma

In a previously studied family with inherited renal cell carcinoma (RCC), RCC was shown to segregate with a constitutional balanced t(3;8)(p14.2;q24.1). In addition, we recently showed that in a RCC tumor from this family the constitutional translocation became unbalanced, suggesting a genetic mechanism that may be associated with the primary genetic events of tumorigenesis. We now report that the RCC tumor cells from this case showed additional cytogenetic alterations, possibly related to tumor progression, which include an additional tumor-specific translocation involving band 14 of chromosome 13. Because this band contains the retinoblastoma (RB) gene, we examined the tumor for aberrations in the RB gene using DNA sequence polymorphism analysis and pulsed-field gel electrophoresis (PFGE), but did not detect alterations in the RB gene.

Von Hippel-Lindau disease associated with an invasive choroid plexus tumour presenting as a middle ear mass

Cerebellar haemangioblastomata and angiomata of the retina are the most common vascular tumours seen in von Hippel-Lindau disease. A definite association between this condition and choroid plexus tumour has not been described previously and its presentation as a middle ear mass is unique.

Fragile 3p14 in patients with von Hippel-Lindau syndrome compared to controls

Lymphocytes from a series of ten patients with von Hippel-Lindau syndrome have been cultured under conditions designed to demonstrate the presence of fragile sites. Compared to a series of controls the subjects with von Hippel-Lindau syndrome show a small but significant increase in the level of FRA3B.

Renal cell carcinoma

Renal cell carcinoma accounts for 3% of all adult cancers and has many unusual features in its presentation, diagnosis, and management. It develops in a significant number of patients with acquired renal cystic disease, a disorder found almost exclusively in chronic hemodialysis patients. Abnormalities of chromosome 3 are frequently found in sporadic and familial forms. Radical nephrectomy remains the only potentially curative therapy for this tumor.

Pancreatic lesions in the von Hippel-Lindau syndrome

Common manifestations of the von Hippel-Lindau syndrome, an autosomally dominant inherited cancer-prone disorder, include retinal angiomatosis, hemangioblastoma of the central nervous system, renal cysts, renal cancer, pheochromocytoma, and epididymal cystadenoma. Multiple cysts and microcystic (serous) cystadenomas of the pancreas have also been reported occasionally in patients afflicted with this syndrome. In the large Freiburg study of the von Hippel-Lindau syndrome composed of 66 affected individuals, pancreatic lesions were systematically studied. Fifty-five living individuals were examined by abdominal ultrasound imaging. Abnormal findings were confirmed by computed tomographic scan and/or magnetic resonance imaging. For an additional 11 decreased patients autopsy data were available. Cystic lesions of the pancreas were found in 10 patients (15%). One of these patients presented with multiple pancreatic cysts as the only manifestation of the syndrome. In one patient, a malignant islet-cell tumor was found at autopsy. Because multiple pancreatic cysts did not cause major clinical symptoms and because follow-up examinations over an average period of 5 years did not show significant progression of the lesions, it is concluded that these patients usually do not require surgical treatment. Abdominal ultrasound screening is recommended for patients at risk as a tool to identify potential von Hippel-Lindau syndrome gene carriers with pancreatic manifestations. In all patients with multiple pancreatic cysts, the von Hippel-Lindau syndrome should be included in the differential diagnosis.

Cytogenetics of renal cell carcinomas associated with von Hippel-Lindau disease

To establish the chromosome pattern, we have analyzed short-term cultures of 24 renal cell carcinomas (RCC) from four patients with von Hippel-Lindau disease (VHL). We evaluated the results together with those for 16 RCCs from two VHL patients karyotyped previously in our laboratory and those of 6 tumors published by others. In all 46 RCCs, the cells had lost the shortest overlapping region of the 3pl3-pter chromosome segment. The rearrangement of 3p was the only karyotype change in 20 tumors. In more than 50% of the tumors, a gain of the shortest overlapping region of the 5122-qter segment was detected. Comparative analysis showed that the chromosome aberrations in RCCs associated with VHL are similar to those found in sporadic RCCs. These results indicate that non-papillary sporadic and VHL-RCCs have common genetic mechanisms that result in the loss of the 3p13-pter region containing one or more putative suppressor genes.

Clustering of features of von Hippel-Lindau syndrome: evidence for a complex genetic locus

von Hippel-Lindau syndrome (HLS), an autosomal-dominant inherited disease, was studied in 92 affected subjects from 29 kindreds. In an initial survey to identify HLS gene carriers, all patients treated at the University of Freiburg for angiomatosis retinae (22), haemangioblastoma of the central nervous system (CNS) (63), and phaeochromocytoma (54) were examined as potential HLS gene carriers. HLS was diagnosed in 86% of the patients with angiomatosis retinae, 19% of the patients with haemangioblastoma of the CNS, and 19% of the patients with phaeochromocytoma. Based on these and on an additional 49 newly diagnosed cases (24 by clinical examination and 25 by pedigree analysis), the calculated prevalence of the disease in the district of Freiburg, Germany, with a population of 1.909 million is 1/38 951. There was a striking tendency for familial clustering of HLS features in affected kindreds. Both angiomatosis retinae and haemangioblastoma of the CNS occurred in most families, whereas renal lesions and/or pancreatic cysts and phaeochromatocytoma were mutually exclusive. This finding suggests that HLS is caused by different mutations within a complex genetic locus, or additional genetic lesions, which cooperate with the HLS gene on chromosome 3p. The data point to a linear sequence of features as follows: phaeochromocytoma, angiomatosis retinae, haemangioblastoma of the CNS, renal lesions, pancreatic cysts, and epididymal cystadenoma.

Nonhomologous chromatid exchange in hereditary and sporadic renal cell carcinomas

For the development of renal cell carcinomas, it has been suggested that a germ-line or somatic mutation occurs on one of the homologous chromosomes 3p, and subsequently the other 3p segment is lost. We have examined the karyotype and/or the allelic combination on chromosomes 3 and 5 by restriction fragment length polymorphism analysis in normal kidney and tumor samples from 28 renal cell carcinomas that developed in two patients with von Hippel-Lindau disease; we then compared the results to those of sporadic tumors. An unbalanced translocation between chromosome 3p and 5q or other chromosomes was found to be the most common aberration. We developed a model of nonhomologous chromatid exchange involving breakpoint clusters at chromosomes 3p13, 3p11.2, 5q22, and 8q11.2. Subsequent chromatid segregation may result in net loss of the 3p segment either (i) in one step or (ii) after a nondisjunctional loss of the derivative chromosome carrying the 3p segment. This general mechanism could also be implicated to explain genetic changes occurring in other types of solid tumors.

Application of molecular cytogenetic techniques to the evaluation of renal parenchymal tumors

This guest editorial discusses the molecular cytogenetic features of human renal parenchymal tumors with an emphasis on their diagnostic usefulness. Important contributions of this review are discrimination (a) between papillary and nonpapillary renal cell carcinomas and (b) between tubulopapillary adenomas and papillary carcinomas. Speculations regarding the histogenesis of different renal parenchymal tumors are presented, with the hope that they may serve to diminish some of the confusion surrounding the classification of these tumors.

Chromogranin A in familial pheochromocytoma: diagnostic screening value, prediction of tumor mass, and post-resection kinetics indicating two-compartment distribution

PURPOSE

Chromogranin A, co-released with catecholamines from the adrenal medullary and sympathetic neuronal vesicles, is elevated in plasma from patients with pheochromocytoma. We assessed its diagnostic screening value, its plasma level in correlation with tumor mass, and its disposition kinetics in familial pheochromocytoma and sporadic pheochromocytoma.

PATIENTS AND METHODS

The sensitivity and specificity of chromogranin A's diagnostic value for pheochromocytoma were established through one kindred with familial pheochromocytoma associated with von Hippel-Lindau syndrome (13 available members) and in seven subjects with sporadic pheochromocytoma. Serial postoperative plasma samples were also obtained (5 minutes to 4 days) from eight subjects with pheochromocytoma in order to study chromogranin A post-resection kinetics. Chromogranin A was measured by radioimmunoassay based on purified pheochromocytoma chromogranin A.

RESULTS

In this kindred, elevations of chromogranin A (greater than 52 ng/mL) were sensitive (83%, five of six) and specific (100%, 10 of 10) in detecting familial pheochromocytoma; these diagnostic values comparable to those achieved by conventional evaluations for pheochromocytoma, such as urinary catecholamines, urinary catecholamine metabolites or imaging methods. Elevated levels of plasma chromogranin A specifically indicated pheochromocytoma, rather than von Hippel-Lindau syndrome gene carrier status. In 13 preoperative subjects with either familial or sporadic pheochromocytoma, plasma chromogranin A concentration predicted tumor size (r = 0.81, p less than 0.01). The change in chromogranin A plasma concentration after pheochromocytoma resection best fit a two-compartment model, with an initial rapid half-life time of 16 minutes, followed by a longer half-life time of 520 minutes. The model also predicted a 23.8:1 compartmental ratio of extravascular/intravascular chromogranin A, suggesting substantial tissue sequestration or binding of chromogranin A.

CONCLUSIONS

(1) Plasma chromogranin A is a valuable (sensitive and specific) diagnostic tool in detecting both familial and sporadic pheochromocytoma. (2) The concentration of plasma chromogranin A predicts the size of the pheochromocytoma. (3) Chromogranin A post-resection kinetics suggest extravascular sequestration of chromogranin A.

Cytogenetic characterization of renal cell carcinoma in von Hippel-Lindau syndrome

We report the case of a 26-year-old man with von Hippel-Lindau syndrome (VHL) and two renal cell carcinomas (RCC), one of which was studied cytogenetically. Chromosomal analysis of the RCC showed a translocation that involved chromosomes 3 and 8 with subsequent loss of the derivative chromosome 8. The patient's peripheral lymphocytes showed a normal karyotype that indicated that there was not a constitutional chromosomal translocation. This is the third reported case of RCC in a patient with VHL in which loss of a portion of the short arm of chromosome 3 (3p) has occurred. Similar chromosomal changes that involve 3p have been reported in both familial and sporadic cases of RCC and have led to speculation that a tumor suppressor gene may be located in this region. Cytogenetic characterization of renal tumors could assume increasing significance in the diagnosis and classification of RCC and potentially may guide therapy. These studies may also lead to a better understanding of the biologic behavior of RCC and result in more informed patient evaluation and counseling.

The cytogenetics of renal tumors. Where do we stand, where do we go?

In this review an attempt is made to give an overview of the present status of cytogenetic research in tumors of the kidney. The results of numerous studies in renal cell carcinoma and adenoma, transitional cell carcinoma, and renal oncocytoma are presented, and the findings from the literature, together with 52 current observations, are analyzed and evaluated with respect to their significance for the understanding of renal malignancies.

Cytogenetic abnormalities in tumors of patients with von Hippel-Lindau disease

Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder that causes the development of benign and malignant tumors in several organ systems. Tumors causing significant morbidity include retinal angioma, cerebellar hemangioblastoma (CH), renal cell carcinoma (RCC), and pheochromocytoma (Pheo). Cytogenetic studies of tumors in VHL patients are rare. Cytogenetic findings in tumors from 12 patients with VHL disease, including four RCCs, three CHs, and five Pheos are presented. Three of the four RCC cases were abnormal. Monosomy 3 or a deletion of 3p was present in all three abnormal cases. Complete or partial trisomy of chromosome 5 was present in two cases. A deletion of 14q, trisomy 7, and a missing Y were each observed in one case. These findings indicate that a deletion of 3p may be a primary cytogenetic change in RCCs associated with VHL disease in addition to playing a role in sporadic RCC. Duplications of 5q and deletions of 14q may be important secondary changes in the progression of the malignant phenotype. No visible cytogenetic abnormalities were observed in the three CHs, or in four of the Pheos. One of the five Pheos was found to exhibit mosaic trisomy 7; its significance is unclear at the present time.

Loss of heterozygosity on 3p in a renal cell carcinoma in von Hippel-Lindau syndrome

A renal cell carcinoma with an unbalanced t(X;3) in a patient with von Hippel-Lindau (VHL) syndrome has previously been reported. This rearrangement suggested loss of genetic material from the short arm of chromosome 3, which we are now able to confirm by restriction fragment length polymorphism analysis of tumor DNA using polymorphic probes derived from 3p. The VHL gene has recently been mapped to 3p, therefore loss of this region in this VHL-related renal cell carcinoma may have cogent significance for tumor development in this interesting cancer-predisposing syndrome.

Cytogenetic studies on three pheochromocytomas derived from patients with von Hippel-Lindau syndrome

Chromosomal analyses of three pheochromocytomas from patients with von Hippel-Lindau syndrome are reported. One pheochromocytoma revealed a normal karyotype, another tumor showed a trisomy 7 as the only chromosomal abnormality, whereas in a further sample a polyclonal chromosome constitution was detected. In addition to a normal 46,XX cell line, four distinct chromosomally abnormal cell lines could be identified. One cell line revealed partial trisomy for the long arm of chromosome 1 and additionally exhibited the phenomenon of telomeric association. Most interestingly, three further cell clones showed rearrangements of chromosome 3 including the region where the von Hippel-Lindau gene was mapped; three rearrangements resulted in a partial or total trisomy of 3p. Our findings are discussed in relation to previously reported cytogenetic and molecular results regarding von Hippel-Lindau syndrome.