Germline mutations in the von Hippel-Lindau (VHL) gene in patients from Poland: disease presentation in patients with deletions of the entire VHL gene

A nonsense mutation in VHL causing Von Hippel-Lindau syndrome in a large Chinese family-a genetic study of familial neoplastic disease

Von Hippel-Lindau (VHL) syndrome is a multi-organ neoplastic disease characterized by highly vascular and cystic tumors in the central nervous system (CNS), retina, and visceral lesions, which are mainly caused by germline mutations in VHL. We aimed to detect novel mutations in VHL gene in families with VHL. Here, a large consanguineous four-generation family with variant phenotypes of VHL syndrome was recruited, and its molecular genetics were tested via Sanger sequencing. And various tools and databases were used to predict the variant pathogenicity, frequency, and protein function. Genetic investigation detected a c.351G > A nonsense mutation in VHL that altered the downstream reading frame and created a premature TGA stop signal, resulting in severely truncated pVHL (p.Trp117Ter). This mutation is absent from most public databases, and functional prediction bioinformatic tools demonstrated that this residue is conserved and that this variant is highly likely to be deleterious. The c.315G > A nonsense mutation in VHL is the causal mutation of this kindred that may lead to clear familial aggregation of VHL syndrome because of the dysfunction of the truncated pVHL.

Immunogenicity in renal cell carcinoma: shifting focus to alternative sources of tumour-specific antigens

Renal cell carcinoma (RCC) comprises a group of malignancies arising from the kidney with unique tumour-specific antigen (TSA) signatures that can trigger cytotoxic immunity. Two classes of TSAs are now considered potential drivers of immunogenicity in RCC: small-scale insertions and deletions (INDELs) that result in coding frameshift mutations, and activation of human endogenous retroviruses. The presence of neoantigen-specific T cells is a hallmark of solid tumours with a high mutagenic burden, which typically have abundant TSAs owing to non-synonymous single nucleotide variations within the genome. However, RCC exhibits high cytotoxic T cell reactivity despite only having an intermediate non-synonymous single nucleotide variation mutational burden. Instead, RCC tumours have a high pan-cancer proportion of INDEL frameshift mutations, and coding frameshift INDELs are associated with high immunogenicity. Moreover, cytotoxic T cells in RCC subtypes seem to recognize tumour-specific endogenous retrovirus epitopes, whose presence is associated with clinical responses to immune checkpoint blockade therapy. Here, we review the distinct molecular landscapes in RCC that promote immunogenic responses, discuss clinical opportunities for discovery of biomarkers that can inform therapeutic immune checkpoint blockade strategies, and identify gaps in knowledge for future investigations.

Retinal hemangioblastoma in a patient with Von Hippel-Lindau disease: A case report and literature review

Background

Retinal hemangioblastoma (RH) is a rare benign tumor and a considerable number of which are caused by Von Hippel-Lindau disease (VHL). Herein, we described a case of VHL-associated RH with retinal detachment who underwent both laser photocoagulation and vitreoretinal surgery and received satisfactory visual recovery. In addition, we reviewed the current diagnosis, genotype-phenotype association, and treatment of VHL-associated RH.

Case description

A 34-year-old woman presented with vision loss in the right eye at our hospital. Fundus photography and angiography showed retinal detachment and multiple large hemangiomas in the right eye. The visual acuity improved significantly after laser photocoagulation and vitreoretinal surgery. Genetic analyses showed a p.Asn78Ser (c.233A>G) heterozygous missense mutation in the VHL gene.

Conclusion

We described a rare case of VHL-associated RH and may provide a new perspective towards diagnosis and treatment of this disease. RH is one of the most common manifestations of VHL and poses a serious threat to vision. Ophthalmic examination methods include fundus examination and fundus photography, etc. The management of the disease emphasizes timely follow-up, early detection of the lesion, and the decision of treatment options according to the size, location and complications of the lesion, including ablation therapy and vitreoretinal surgery. Clinicians should strengthen the understanding of this rare disease for early detection and treatment.

A meta-analysis of different von Hippel Lindau mutations: are they related to retinal capillary hemangioblastoma?

Retinal capillary hemangioblastomas (RCH) is a benign tumor that represents the initial manifestation in roughly half of Von Hippel Lindau (VHL) patients. They may also occur sporadically without systemic involvement. A first meta-analysis study was investigated to estimate the prevalence of Retinal capillary hemangioblastoma (RCH) in Von Hippel Lindau (VHL) syndrome, and its relation to type and location of mutations in VHL gene. The electronic databases of PubMed, Scopus, Embase, and Google Scholar were utilized to find eligible papers published up to May 2020. Lastly, after the different prevalence of RCH in Europe compared to other continents was noted, we decided to consider European and non-European patients separately. The Random effect model was used to evaluate the relation between developing RCH and types of mutations. The overall prevalence of RCH among VHL patients is about 47%. The prevalence of RCH was significantly higher in Europe in comparison with non-Europeans (p value < 0.001). Overall, the differences between the prevalence of RCH among different mutation types were not statistically significant. However, in Europe, the prevalence of RCH was significantly higher in patients with truncation mutation (p value = 0.007). In Europe, the RCH in VHL patients who had a mutation in exon 2 was significantly lower in comparison with exon 1 (p value = 0.001); but in non-Europeans, the prevalence of RCH in VHL patients that involved exon 2 was significantly higher in comparison with VHL patients with a mutation in exon1 (p value = 0.012). The highest risk of developing RCH was reported among Europeans. Overall, this study showed that the prevalence of RCH in VHL syndrome is not related to type or location of mutations and difference of RCH prevalence is probably depends on other genetic or environmental factor that should be considered in subsequent studies.

von Hippel-Lindau disease: Updated guideline for diagnosis and surveillance

von Hippel Lindau disease (vHL) is caused by a hereditary predisposition to multiple neoplasms, especially hemangioblastomas in the retina and CNS, renal cell carcinomas (RCC), pheochromocytomas, neuroendocrine pancreatic tumours (PNET) and endolymphatic sac tumours. Evidence based approaches are needed to ensure an optimal clinical care, while minimizing the burden for the patients and their families. This guideline is based on evidence from the international vHL literature and extensive research of geno- and phenotypic characteristics, disease progression and surveillance effect in the national Danish vHL cohort. We included the views and preferences of the Danish vHL patients, ensured consensus among Danish experts and compared with international recommendations. RECOMMENDATIONS: vHL can be diagnosed on clinical criteria, only; however, in most cases the diagnosis can be supported by identification of a pathogenic or likely pathogenic variant in VHL. Surveillance should be initiated in childhood in persons with, or at risk of, vHL, and include regular examination of the retina, CNS, inner ear, kidneys, neuroendocrine glands, and pancreas. Treatment of vHL manifestations should be planned to optimize the chance of cure, without unnecessary sequelae. Most manifestations are currently treated by surgery. However, belzutifan, that targets HIF-2α was recently approved by the U.S. Food and Drug Administration (FDA) for adult patients with vHL-associated RCC, CNS hemangioblastomas, or PNETs, not requiring immediate surgery. Diagnostics, surveillance, and treatment of vHL can be undertaken successfully by experts collaborating in multidisciplinary teams. Systematic registration, collaboration with patient organisations, and research are fundamental for the continuous improvement of clinical care and optimization of outcome with minimal patient inconvenience.

Pheochromocytomas and paragangliomas in von Hippel-Lindau disease: not a needle in a haystack

OBJECTIVE

Pheochromocytomas are a hallmark feature of von Hippel-Lindau disease (vHL). To our knowledge, this is the first systematic review with meta-analysis evaluating the frequency of pheochromocytomas and/or paragangliomas (PPGLs) in patients with vHL, as well as among patients with different vHL subtypes.

DESIGN

Systematic review with meta-analysis.

METHODS

We searched on MEDLINE, Scopus, and Web of Science. We included primary studies assessing participants with vHL and reporting on the frequency of PPGL. We performed random-effects meta-analysis to quantitatively assess the frequency of PPGL, followed by meta-regression and subgroup analysis. Risk of bias analysis was performed to assess primary studies' methodological quality.

RESULTS

We included 80 primary studies. In 4263 patients with vHL, the pooled frequency of PPGL was 19.4% (95% CI = 15.9-23.6%, I2 = 86.1%). The frequency increased to 60.0% in patients with vHL type 2 (95% CI = 53.4-66.3%, I2 = 54.6%) and was determined to be of 58.2% in patients with vHL type 2A (95% CI = 49.7-66.3%, I2 = 36.2%), compared to 49.8% in vHL type 2B (95% CI = 39.9-59.7%, I2 = 42.7%), and 84.1% in vHL type 2C (95% CI = 75.1-93.1%, I2 = 0%). In meta-regression analysis, more recent studies were associated with a higher frequency of PPGL. All studies had at least one internal validity item classified as 'high risk of bias,' with 13% studies having low risk of bias in all external validity items.

CONCLUSIONS

PPGLs are a common manifestation of vHL. Despite methodological limitations and differences across primary studies, our results point to the importance of PPGL screening in patients with vHL.

Novel and recurrent germline mutations in the VHL gene in 5 Arab patients with Von Hippel-Lindau disease

Inherited germline mutations in the VHL gene cause predisposition to Von Hippel-Lindau (VHL) disease. Patients exhibit benign and cancerous lesions in multiple tissues, including hemangioblastomas, clear cell renal cell carcinoma, cysts in kidneys and pancreas, and pheochromocytomas. Although pathogenic germline mutations in the VHL gene have been widely described in different populations, only a single mutation was previously reported in a family from mixed Arab-Persian ethnicity. Here, we present five Arab patients with two new and two recurrent germline mutations in the VHL gene. These mutations include three in-frame deletions and a missense mutation. Infrequent in-frame deletions in previously described patients from other populations, as well as the presence of new mutations, suggests a distinct spectrum of VHL gene mutations in Arab patients. While pulmonary manifestation has been described rarely in VHL disease, we have identified two patients with a recurrent p.Phe76del in-frame deletion exhibiting multiple nodules in lungs. We also describe a first-ever in-frame deletion in the VHL gene in a patient with VHL type 2C disease, exhibiting bilateral pheochromocytoma. Overall, the study provides an insight into the genotype-phenotype relationship of VHL disease in Arab patients and provides a comparison with previously described patients from other ethnicities.

Novel genotype-phenotype correlations in five Chinese families with Von Hippel-Lindau disease

CONTEXT

Von Hippel-Lindau (VHL) disease manifests as a variety of benign and malignant neoplasms. Previous studies of VHL disease have documented several genotype-phenotype correlations; however, many such correlations are still unknown. Increased identification of new mutations and patients with previously described mutations will allow us to better understand how VHL mutations influence disease phenotypes.

PATIENTS AND DESIGN

A total of 45 individuals from five unrelated families were evaluated, of which 21 patients were either diagnosed with VHL disease or showed strong evidence related to this disease. We compared the patients' gene sequencing results with their medical records including CT or MRI scans, eye examinations and laboratory/pathological examinations. Patients were also interviewed to obtain information regarding their family history.

RESULTS

We identified four missense mutations: c.239G>T (p.Ser80Ile), linked with VHL Type 2B, was associated with renal cell carcinoma, pheochromocytoma and hemangioma in the cerebellum; c.232A>T (p.Asn78Tyr) manifested as RCC alone and likely caused VHL Type 1; c.500G>A (p.Arg167Gln) mutation was more likely to cause VHL Type 2 than Type 1 as it preferentially induced Pheo and HB in the retina, cerebellum and spinal cord; c.293A>G (p.Try98Cys) was associated with Pheo and thus likely induced VHL Type 2.

CONCLUSIONS

Characterizing VHL disease genotype-phenotype correlations can enhance the ability to predict the risk of individual patients developing different VHL-related phenotypes. Ultimately, such insight will improve the diagnostics, surveillance and treatment of VHL patients.

PRECIS

Four missense mutations in VHL have been identified in 21 individuals when five unrelated Chinese families with VHL disease were analyzed; VHL mutations are highly associated with unique disease phenotypes.

Genotype and phenotype correlation in von Hippel-Lindau disease based on alteration of the HIF-α binding site in VHL protein

PURPOSE

Von Hippel-Lindau (VHL) disease is a rare hereditary cancer syndrome that reduces life expectancy. We aimed to construct a more valuable genotype-phenotype correlation based on alterations in VHL protein (pVHL).

METHODS

VHL patients (n = 339) were recruited and grouped based on mutation types: HIF-α binding site missense (HM) mutations, non-HIF-α binding site missense (nHM) mutations, and truncating (TR) mutations. Age-related risks of VHL-associated tumors and patient survival were compared.

RESULTS

Missense mutations conferred an increased risk of pheochromocytoma (HR = 1.854, p = 0.047) compared with truncating mutations. The risk of pheochromocytoma was lower in the HM group than in the nHM group (HR = 0.298, p = 0.003) but was similar between HM and TR groups (HR = 0.901, p = 0.810). Patients in the nHM group had a higher risk of pheochromocytoma (HR = 3.447, p < 0.001) and lower risks of central nervous system hemangioblastoma (CHB) (HR = 0.700, p = 0.045), renal cell carcinoma (HR = 0.610, p = 0.024), and pancreatic tumor (HR = 0.382, p < 0.001) than those in the combined HM and TR (HMTR) group. Moreover, nHM mutations were independently associated with better overall survival (HR = 0.345, p = 0.005) and CHB-specific survival (HR = 0.129, p = 0.005) than HMTR mutations.

CONCLUSION

The modified genotype-phenotype correlation links VHL gene mutation, substrate binding site, and phenotypic diversity (penetrance and survival), and provides more accurate information for genetic counseling and pathogenesis studies.

Whole exome sequencing identified genetic variations in Chinese hemangioblastoma patients

Hemangioblastomas (HBs) are uncommon tumors characterized by the presence of inactivating alterations in the von Hippel-Lindau (VHL) gene in inherited cases and by infrequent somatic mutation in sporadic entities. We performed whole exome sequencing on 11 HB patients to further elucidate the genetics of HBs. A total of 270 somatic variations in 219 genes, of which there were 86 mutations in 67 genes, were found in sporadic HBs, and 184 mutations were found in 154 genes in familial HBs. C: G>T: A and T: A>C: G mutations are relatively common in most HB patients. Genes harboring the most significant mutations include PCDH9, KLHL12, DCAF4L1, and VHL in sporadic HBs, and ZNF814, DLG2, RIMS1, PNN, and MUC7 in familial HBs. The frequency of CNV varied considerably within sporadic HBs but was relatively similar within familial HBs. Five genes, including OTOGL, PLCB4, SCEL, THSD4, and WWOX, have CNVs in the six patients with sporadic HBs, and three genes, including ABCA6, CWC27, and LAMA2, have CNVs in the five patients with familial HBs. We found new genetic mutations and CNVs that might be involved in HBs; these findings highlight the complexity of the tumorigenesis of HBs and pinpoint potential therapeutic targets for the treatment of HBs.

[Genetic analysis of a family with Von Hippel-Lindau syndrome]

Von Hippel-Lindau syndrome (VHL) is an autosomal dominant inherited disease associated with mutations in the VHL tumour suppressor gene located on chromosome 3p25. VHL is characterized by the development of multiple malignant and benign tumours in the central nervous system and internal organs, including liver, pancreas and the adrenal gland. More than 823 different mutations of the VHL gene have currently been identified. In the present study we describe the case of a family affected by VHL treated at the University Hospital of La Ribera and the results of the genetic analysis of three relatives, identifying the mutation R167G in exon 3 of VHL gene as the cause of VHL syndrome in this family.

Prevalence, birth incidence, and penetrance of von Hippel-Lindau disease (vHL) in Denmark

Von Hippel-Lindau disease (vHL) is a rare hereditary tumour predisposition with multiorgan involvement that is not always easily recognized. The disease is reported to be almost fully penetrant at age 60 years. Previous estimates of vHL prevalence and incidence are all regional and vary widely. Most are >20 years old and prone to selection bias because of inclusion of only clinically affected vHL patients who were diagnosed before genetic testing was available. In an unselected cohort of all known Danish carriers of a disease-causing VHL variant, we assessed vHL penetrance on a national basis. We further used national health registers to identify individuals who fulfilled the clinical diagnostic vHL criteria based on their registered diagnostic codes, but had not been diagnosed with vHL. We also assessed the medical histories of first-degree relatives to identify familial cases. This study gives the first national estimates of vHL prevalence (1 in 46 900 individuals) and birth incidence (1 in 27 300 live births). vHL has been underdiagnosed in Denmark, and as many as 25% of the overall vHL cohort (diagnosed+undiagnosed patients) have a missed diagnosis in spite of fulfilling the international diagnostic criteria. We found an overall penetrance of 87% at age 60 years. When considering only vHL patients who have not attended surveillance, 20% will still be asymptomatic at age 60 years. This should be considered in the context of genetic counselling, especially when assessing the risk of vHL in asymptomatic adult first-degree relatives who are often not genetically tested.

VHL Germline Mutations in Argentinian Patients with Clinical Diagnoses or Single Typical Manifestations of Type 1 von Hippel-Lindau Disease

AIMS

von Hippel-Lindau (VHL) disease is caused by mutations in the VHL tumor suppressor gene. As tumors that develop in the context of VHL also occur in a sporadic context, the frequency of this syndrome may be underestimated. Our aim was to identify VHL gene mutations in Argentinian patients who fulfilled the clinical criteria for type 1 VHL disease and in patients with VHL-associated manifestations that did not meet these criteria.

METHODS

We performed a retrospective cohort study, including patients who met current diagnostic criteria for type 1 VHL (Group 1, n = 19) and patients with VHL-associated manifestations that did not meet these criteria (Group 2, n = 21). Genomic DNA was extracted from peripheral blood leukocytes. Mutation analysis involved DNA sequencing, while large deletions were determined by universal primer quantitative fluorescent multiplex polymerase chain reaction (UPQFM-PCR) and multiplex ligation-dependent probe amplification (MLPA) analysis.

RESULTS

VHL mutations were detected in 16/19 (84.2%) patients in Group 1 and included: gross deletions (4/16); nonsense mutations (6/16); frameshift mutations (4/16); missense mutations (1/16); and splicing mutations (1/16). Three of these mutations were novel. No alterations were found in 3 of 19 VHL patients. In Group 2, one nonsense VHL mutation was detected in a young patient with a solitary central nervous system hemangioblastoma without familial history. A study of 30 first-degree relatives revealed four carriers with VHL mutations.

CONCLUSIONS

We found three novel mutations in the VHL gene in our population. Our results emphasize the importance of a complete genetic study of VHL to confirm type 1 VHL disease, not only in patients with clinical diagnostic criteria but also in those presenting a single typical manifestation.

Genotype-phenotype analysis of von Hippel-Lindau syndrome in Korean families: HIF-α binding site missense mutations elevate age-specific risk for CNS hemangioblastoma

BACKGROUND

von Hippel-Lindau (VHL) disease is a rare hereditary tumor syndrome caused by VHL gene mutations that is characterized by heterogeneous phenotypes such as benign/malignant tumors of the central nervous system, retina, kidney, adrenal gland, and pancreas. The genotype-phenotype correlation has not been well characterized in the Korean population so far. Therefore, this study aimed to evaluate the VHL mutation spectrum and genotype-phenotype correlations in Korean VHL patients.

METHODS

Thirteen unrelated subjects with VHL mutations were included. Direct sequencing and multiplex ligation-dependent probe amplification were performed. Consequently, the clinical manifestations and family histories of the subjects were evaluated.

RESULTS

We identified 10 different VHL mutations. The c.160_161delAT frameshift mutation was novel. Missense mutations clustered in 2 domains (α domain in exon 1; β domain in exon 3). The most frequently observed mutation was c.208G > A (p.Glu70Lys). Milder phenotypes were observed in subjects with de novo mutations. Age-specific risk for CNS hemangioblastoma was significantly higher in subjects carrying missense mutations within the HIF-α binding site (P < 0.05).

CONCLUSIONS

This study provides insight into the genotype-phenotype correlation in that amino acid substitutions in the HIF-α binding site may predispose patients to age-related risks of CNS hemangioblastoma.

Clinical and genetic investigation of a multi-generational Chinese family afflicted with Von Hippel-Lindau disease

Background:

Von Hippel-Lindau (VHL) disease is a hereditary tumor disorder caused by mutations or deletions of the VHL gene. Few studies have documented the clinical phenotype and genetic basis of the occurrence of VHL disease in China. This study armed to present clinical and genetic analyses of VHL within a five-generation VHL family from Northwestern China, and summarize the VHL mutations and clinical characteristics of Chinese families with VHL according to previous studies.

Methods:

An epidemiological investigation of family members was done to collect the general information. A retrospective study of clinical VHL cases was launched to collect the relative clinical data. Genetic linkage and haplotype analysis were used to make sure the linkage of VHL to disease in this family. The VHL gene screening was performed by directly analyzing DNA sequence output. At last, we summarized the VHL gene mutation in China by the literature review.

Results:

A five-generation North-western Chinese family afflicted with VHL disease was traced in this research. The family consisted of 38 living family members, of whom nine were affected. The individuals afflicted with VHL exhibited multi-organ tumors that included pheochromocytomas (8), central nervous system hemangioblastomas (3), pancreatic endocrine tumors (2), pancreatic cysts (3), renal cysts (4), and paragangliomas (2). A linkage analysis resulted in a high maximal LOD score of 8.26 (theta = 0.0) for the marker D3S1263, which is in the same chromosome region as VHL. Sequence analysis resulted in the identification of a functional C>T transition mutation (c. 499 C>T, p.R167W) located in exon 3 of the 167^th codon of VHL. All affected individuals shared this mutation, whereas the unaffected family members and an additional 100 unrelated healthy individuals did not. To date, 49 mutations have been associated with this disease in Chinese populations. The most frequent VHL mutations in China are p.S65 W, p.N78 S, p.R161Q and p.R167 W.

Conclusions:

The results supported the notion that the genomic sequence that corresponds to the 167^th residue of VHL is a mutational hotspot. Further research is needed to clarify the molecular role of VHL in the development of organ-specific tumors.

Large deletion causing von Hippel-Lindau disease and hereditary breast cancer syndrome

Patients with intragenic mutations of the VHL gene have a typical disease presentation. However in cases of large VHL gene deletions which involve other genes in the proximity of the VHL gene a presentation of the disease can be different.

To investigate whether large VHL deletions that remove the FANCD2 gene have an effect on the disease phenotype, we studied a family with a 50 kb large deletion encompassing these two genes. Four patients in this family were affected by VHL-related lesions. However one carrier of the deletion also had bilateral ductal breast cancer at age 46 and 49. Both tumors were of ~2 cm in diameter. On one side lymph nodes were affected. One tumor was ER- and PR-negative (HER2 s unknown) and the second was ER- and PR-positive, and HER2-negative.

Our study suggests that a deletion of FANCD2 gene, an important gene in the DNA repair pathway, may be associated with an increased risk of breast cancer, but further studies are needed in this regard.

Mosaicism in von Hippel-Lindau disease with severe renal manifestations

von Hippel-Lindau (VHL) disease is an inheritable multisystem tumor syndrome characterized by multiple benign and malignant tumors affecting multiple organs. VHL is the result of a germline mutation in the VHL tumor suppressor gene. Molecular genomic analysis routinely confirms the clinical diagnosis. However, the use of molecular diagnostic methods can often be insufficient for the detection of mosaic germline VHL mutations, making the diagnosis of some cases of VHL difficult. Here, we report the case of a VHL mosaic patient with bilateral renal lesions in the absence of other VHL-associated lesions. A VHL mutation was not originally detected by routine molecular testing. Nonetheless, the detection of a heterozygous c.194C>G (p.Ser65Trp) VHL mutation in the patient's daughter prompted further genetic assessment and eventually resulted in the finding of a mosaic c.194C>G (p.Ser65Trp) VHL mutation in the patient. The mutation rate was 18.8 ± 3.84% in peripheral leukocytes. As the frequency of VHL mosaicism remains underdetermined, the possibility of a diagnosis of mosaic VHL should be considered in patients with both typical and atypical VHL-associated manifestations.

Three novel germ-line VHL mutations in Hungarian von Hippel-Lindau patients, including a nonsense mutation in a fifteen-year-old boy with renal cell carcinoma

BACKGROUND

Von Hippel-Lindau disease is an autosomal dominantly inherited highly penetrant tumor syndrome predisposing to retinal and central nervous system hemangioblastomas, renal cell carcinoma and phaeochromocytoma among other less frequent complications.

METHODS

Molecular genetic testing of the VHL gene was performed in five unrelated families affetced with type I VHL disease, including seven patients and their available family members.

RESULTS

Molecular genetic investigations detected three novel (c.163 G > T, c.232A > T and c.555C > A causing p.Glu55X, p.Asn78Tyr and p.Tyr185X protein changes, respectively) and two previously described (c.340 + 1 G > A and c.583C > T, resulting in p.Gly114AspfsX6 and p.195GlnX protein changes, respectively) germline point mutations in the VHL gene. Molecular modeling of the VHL-ElonginC-HIF-1alpha complex predicted that the p.Asn78Tyr amino acid exchange remarkably alters the 77-83 loop structure of VHL protein and destabilizes the VHL-HIF-1alpha complex suggesting that the mutation causes type I phenotype and has high risk to associate to renal cell carcinoma. The novel p.55X nonsense mutation associated to bilateral RCC and retinal angioma in a 15-year-old male patient.

CONCLUSION

We describe the earliest onset renal cell carcinoma in VHL disease reported so far in a 15-year-old boy with a nonsense VHL mutation. Individual tailoring of screening schedule based on molecular genetic status should be considered in order to diagnose serious complications as early as possible. Our observations add to the understanding of genotype-phenotype correlation in VHL disease and can be useful for genetic counseling and follow-up of VHL patients.

DNA and RNA analyses in detection of genetic predisposition to cancer

During the past decade many new molecular methods for DNA and RNA analysis have emerged. The most popular thus far have been SSCP, HET, CMC, DGGE, RFLP or ASA, which have now been replaced by methods that are more cost effective and less time consuming. Real-time amplification techniques and particularly those with the capacity of multiplexing have become commonly used in laboratory practice. Novel screening methods enable the very rapid examination of large patients series. Use of liquid handling robotics applied to the isolation of DNA or RNA, the normalisation of sample concentration, and standardization of target amplification by PCR have also contributed to a reduced risk of sample contamination and have resulted in laboratory analysis being easier and faster.

The aim of this study is the introduction of a few modern techniques, most commonly used in detection of genetic predisposition to cancer.

Family history of von Hippel-Lindau disease was uncommon in Chinese patients: suggesting the higher frequency of de novo mutations in VHL gene in these patients

Von Hippel-Lindau (VHL) disease is an autosomal dominant familial cancer syndrome caused by germline mutations in VHL tumor suppressor gene. It is characterized by hemangioblastoma in central nervous system and retina, renal cell carcinoma or cyst, pheochromocytoma, pancreatic cyst and tumor, endolymphatic-sac tumor, and papillary cystadenoma in epididymis and broad ligament. Here, we used PCR-direct sequencing and universal primer quantitative fluorescent multiplex PCR (UPQFM-PCR) to detect VHL mutations in 16 patients clinically diagnosed with VHL disease. PCR-direct sequencing detected 12 germline mutations (75%, 12/16), in which a novel mutation of c.451A>T/p.Ile151Phe found in one proband had not been reported previously. UPQFM-PCR found two large deletions (12.5%, 2/16). The two remaining patients carried non-typical disease-causing mutations, including one silent mutation (c.481C>A/p.Arg161Arg) and one mutation in 3'-UTR (c.642+70C>A). Remarkably, 56.3% (9/16) probands did not have family history of VHL disease, suggesting the higher frequency of de novo mutations in Chinese patients. We also summarized Chinese VHL disease patients with VHL mutation findings published in the literature to provide information about the spectrum of VHL mutations in Chinese VHL disease patients.

A case of carotid body paraganglioma and haemangioblastoma of the spinal cord in a patient with the N131K missense mutation in the VHL gene

The article describes paraganglioma case in woman with von Hippel–Lindau disease. She was found to be a carrier of a rare germline mutation in the VHL gene (393C>A; N131K). The patient developed large, untypical for von Hippel–Lindau disease, carotid body paraganglioma at the common carotid artery bifurcation. The carotid body paraganglioma coexisted with the haemangioblastoma situated intramedullary in region C5/C6. The haemangioblastoma reached the right-sided dorsal part of the spinal cord in section C5/C6. It produced radicular symptoms within C5/C6, followed by the later paresis of the right limbs. The haemangioblastoma was resected completely. Twelve months after the operation, the spinal symptoms receded and the carotid body paraganglioma still was asymptomatic. The current case of carotid body paraganglioma in patient with the 393C>A (N131K) missense mutation in the VHL gene, supports association of this specific mutation and VHL disease type 2, and suggests its correlation with susceptibility to paragangliomas.

Germline VHL gene mutations in Hungarian families with von Hippel-Lindau disease and patients with apparently sporadic unilateral pheochromocytomas

OBJECTIVE

Von Hippel-Lindau (VHL) disease is a hereditary tumor syndrome caused by mutations or deletions of the VHL tumor-suppressor gene. Germline VHL gene alterations may be also present in patients with apparently sporadic pheochromocytoma (ASP), although a wide variation in mutation frequencies has been reported in different patient cohorts.

DESIGN

Herein, we report the analysis of the VHL gene in Hungarian families with VHL disease and in those with ASP.

METHODS

Seven families (35 members) with VHL disease and 37 unrelated patients with unilateral ASP were analyzed. Patients were clinically evaluated and the VHL gene was analyzed using direct sequencing, multiplex ligation-dependent probe amplification, and real-time PCR with SYBR Green chemistry.

RESULTS

Disease-causing genetic abnormalities were identified in each of the seven VHL families and in 3 out of the 37 patients with ASP (one nonsense and six missense mutations, two large gene deletions and one novel 2 bp deletion). Large gene deletions and other genetic alterations resulting in truncated VHL protein were found only in families with VHL type 1, whereas missense mutations were associated mainly, although not exclusively, with VHL type 2B and type 2C.

CONCLUSIONS

The spectrum of VHL gene abnormalities in the Hungarian population is similar to that observed in Western, Japanese, or Chinese VHL kindreds. The presence of VHL gene mutations in 3 out of the 37 patients with ASP suggests that genetic testing is useful not only in patients with VHL disease but also in those with ASP.

A vitronectin M381T polymorphism increases risk of hemangioblastoma in patients with VHL gene defect

Hemangioblastomas, highly vascular tumors, occur sporadically or associated with von Hippel-Lindau (VHL) disease. Diverse mutations in the VHL gene inactivate the VHL protein and constitute the molecular etiology of the disease. Changes in VHL gene were analyzed in patients with multiplex ligation-dependent probe amplification and single-strand conformation polymorphism analyses. We report here that other angiogenesis-related changes in vitronectin were identified with 2D electrophoresis of plasma samples and restriction fragment length polymorphisms. Our findings revealed that most patients (80.0%) with a familial VHL deletion carried the threonine (T) allele at vitronectin codon 381. Adults simultaneously carrying a VHL defect and the T allele were 5.0-fold more likely to be affected by VHL disease than were methionine/methionine (M/M) homozygotes carrying a VHL defect. Patients with sporadic hemangioblastoma, C-terminally truncated VHL protein or a large deletion in the VHL gene, and the T allele were 18.0-fold more likely to develop recurrent disease. Taken together, individuals with mutated VHL are more likely to be affected by familial or recurrent sporadic hemangioblastoma when carrying the M/T or T/T genotype at codon 381 of vitronectin.

Improved detection of germline mutations in Korean VHL patients by multiple ligation-dependent probe amplification analysis

von Hippel-Lindau (VHL) disease is an autosomal dominant inherited tumor syndrome characterized by the development of tumors in the eye, brain, spinal cord, inner ear, adrenal gland, pancreas, kidney, and epididymis, associated with germline mutations in the VHL gene. We used sequentially sequencing method and multiple ligation-dependent probe amplification (MLPA) analysis and detected germline mutations in the VHL in 15/15 (100%) of VHL patients fulfilling the clinical criteria. Of the 15 distinct mutations detected, large deletions were detected in 5/15 (33.3%) patients, including 4/15 (26.7%) partial deletions and 1/15 (6.6%) deletion of the entire VHL gene by MLPA and the remainder were point mutations detected by sequencing method, of which five mutations were novel. Using MLPA analysis, we detected large deletions including both partial deletions and complete gene deletion, which has not been reported in Korean VHL patients. In conclusion, sequential application of sequencing method and MLPA analysis might make possible to identify germline mutations in most patients with VHL.

Von Hippel-Lindau (VHL) disease: an update on the clinico-pathologic and genetic aspects

von Hippel-Lindau (VHL) disease is an inherited multisystem familial cancer syndrome caused by mutations of the VHL gene on chromosome 3p25. A wide variety of neoplastic processes are known to be associated with VHL disease. The consequences of the VHL mutations and the pathway for tumor development continue to be elucidated. This paper will detail the variety of tumors associated with VHL disease and discuss the genetic mechanisms that lead to the predisposition for neoplasia.

Germline mutations in the von Hippel-Lindau disease (VHL) gene in mainland Chinese families

BACKGROUND

von Hippel-Lindau (VHL) disease is a hereditary cancer syndrome caused by germline mutations in the VHL gene. To date, more than 500 VHL families have been reported worldwide. However, few information is available about VHL germline mutations in mainland Chinese families.

OBJECTIVE

To provide some preliminary information about the germline VHL mutations in mainland Chinese population.

METHODS

A total of 27 index patients suspected of having VHL disease from unrelated Chinese families were studied by using direct DNA sequencing analysis and universal primer quantitative fluorescent multiplex polymerase chain reaction.

RESULTS

The VHL germline mutations were detected in 26 (96%) probands. A total of 20 intragenic mutations (77%) were identified consisting of 12 missenses, 5 nonsenses, 2 micro-deletions and 1 novel intron mutation (IVS1-38C>T). Six large deletions (23%) were detected including four partial deletions and two complete deletions. Furthermore, a C>T substitution at nucleotide 470 (Pro86Leu) was observed in two unrelated Chinese families. Of note, two mutations (Asn78Ser and Ser80Ile) previously characterized as VHL type I mutations in Western VHL were associated with the type II Chinese family. In addition, a VHL germline mutation was also identified in a proband who did not fulfill the clinical diagnostic criteria for VHL disease.

CONCLUSIONS

The spectrum of VHL germline mutations in mainland Chinese population is similar to that observed in Western population, and Genetic testing can be powerful in diagnosis and clinical management of VHL disease.

Ser80Ile mutation and a concurrent Pro25Leu variant of the VHL gene in an extended Hungarian von Hippel-Lindau family

Von Hippel-Lindau disease (VHL) is a rare autosomal dominant disease characterized by development of cystic and tumorous lesions at multiple sites, including the brain, spinal cord, kidneys, adrenals, pancreas, epididymis and eyes. The clinical phenotype results from molecular abnormalities of the VHL tumor suppressor gene, mapped to human chromosome 3p25-26. The VHL gene encodes two functionally active VHL proteins due to the presence of two translational initiation sites separated by 53 codons. The majority of disease-causing mutations have been detected downstream of the second translational initiation site, but there are conflicting data as to whether few mutations located in the first 53 codons, such as the Pro25Leu could have a pathogenic role. In this paper we report a large Hungarian VHL type 2 family consisting of 32 members in whom a disease-causing AGT80AAT (Ser80Ile) c.239G>A, p.Ser80Ile mutation, but not the concurrent CCT25CTT (Pro25Leu) c.74C>T, p.Pro25Leu variant co-segregated with the disease. To our knowledge, the Ser80Ile mutation has not been previously described in VHL type 2 patients with high risk of pheochromocytoma and renal cell cancer. Therefore, this finding represents a novel genotype-phenotype association and VHL kindreds with Ser80Ile mutation will require careful surveillance for pheochromocytoma. We concluded that the Pro25Leu variant is a rare, neutral variant, but the presence such a rare gene variant may make genetic counseling difficult.

Genetic Counseling in Renal Masses

All urologists have faced patients suffering a renal cancer asking for the occurrence of the disease in their offspring and very often the answer to this question has not been well founded from the scientific point of view, and only in few cases a familial segregation tree is performed. The grate shift seen in the detection of small renal masses and renal cancer in the last decades will prompt us to know the indications for familial studies, which and when are necessary, and probably to refer those patients with a suspected familial syndrome to specialized oncological centers where the appropriate molecular and familial studies could be done. Use of molecular genetic testing for early identification of at-risk family members improves diagnostic certainty and would reduce costly screening procedures in at-risk members who have not inherited disease-causing mutations. This review will focus on the molecular bases of familial syndromes associated with small renal masses and the indications of familial studies in at-risk family members.

Loss of the actin regulator HSPC300 results in clear cell renal cell carcinoma protection in Von Hippel-Lindau patients

Clear cell renal cell carcinoma (ccRCC) is the most common malignant neoplasm of the kidney. The majority of hereditary and sporadic ccRCC cases are associated with germline and somatic mutations in the Von Hippel-Lindau gene (VHL), respectively. Gross deletions at the VHL locus can result either in ccRCC or in a mild clinical phenotype, with the absence of ccRCC development. Our goal in this study was to identify the molecular basis responsible for these differences in the clinical behavior in order to predict patients' phenotype. Using multiplex ligation-dependent amplification (MLPA), we identified and characterized gross VHL deletions in Spanish VHL families. A candidate gene related to this clinical association, HSPC300, was identified and depleted by RNA interference. It was possible to narrow the susceptibility region related to the mild clinical phenotype down to approximately 14 kb that included HSPC300 (C3orf10), a regulator of actin dynamics and cytoskeleton organization. Whereas 9 out of 10 families with ccRCC retained HSPC300 in the germline, loss of the HSPC300 locus was associated with mild clinical presentation of the disease in 6 out of 8 families. In fact, genetic depletion of HSPC300 resulted in cytoskeleton abnormalities and cytokinesis arrest in several tumor cell lines including ccRCC cells, suggesting that tumor cell proliferation was compromised in the absence of HSPC300. These clinical and functional data indicate a relevant function of HSPC300 in tumor cell progression, and suggest future therapeutic strategies based upon the inhibition of HSPC300 in renal cell carcinoma and possibly on other cancers.

Characteristic genomic imbalances in pediatric pheochromocytoma

Pheochromocytoma (PCC) in children is rare, genetically not well described, and often related to a poor prognosis. We detected genomic imbalances in all 14 tumors from children analyzed by comparative genomic hybridization. A combinatorial loss of chromatin from 3p and 11p was a common feature in 10 of 14 (72%) patients, which was a result of either a loss of a total chromosome 3 and a total chromosome 11 in 6 of 10 patients, or confined deletions of their p arms in 4 of 10 patients. All patients exhibiting a loss of 3p and 11p carried VHL mutations. The VHL mutations were constitutive in 9 cases and somatic and restricted to tumor DNA in the remaining tumor. On the other hand, VHL mutations were absent in 4 patients, 2 who had other familial syndromes (NF1, SDHD) and 2 with unknown etiology. Our data show that the pattern of imbalances in the tumor DNA of PCC patients strongly correlated with an underlying familial VHL mutation. Furthermore, we show that true sporadic PCC is rare in childhood. Thus, children with PCC should be checked for a related predisposing gene. This would also identify familial syndrome patients requiring long-term monitoring for other syndrome-related malignancies.

Multifocal renal oncocytoma in a patient with Von Hippel-Lindau mutation

Von Hippel-Lindau disease (VHL) is a rare genetic disease with a lifetime risk of clear cell renal cell carcinoma in approximately 70% of cases. We present a case of a 63-year-old man with bilateral, multifocal renal masses. Genetic testing results were consistent with a VHL deletion. The patient had no other disease manifestations consistent with VHL. The patient underwent staged bilateral nephron-sparing procedures. Pathology of all renal masses revealed oncocytoma. To our knowledge, we describe the first reported case of multiple renal oncocytomas in a male patient with a germline VHL mutation.

Mutations in the von hippel-lindau tumour suppressor gene in central nervous system hemangioblastomas

Central nervous system hemangioblastomas (cHAB) are rare tumours which most commonly arise in the cerebellum. Most tumours are sporadic, but as many as one third of cHABs occur in the course of the hereditary disorder - von Hippel-Lindau disease (VHL). In order to diagnose new VHL families in Poland we performed sequencing of the entire VHL gene in archival material (paraffin embedded hemangioblastoma tissues) in a large series of 203 unselected patients with cHAB. VHL gene mutations were detected in 70 (41%) of 171 tumour samples from which DNA of relatively good quality was isolated. We were able to obtain blood samples from 19 of mutation positive cases. Eight (42%) of these harboured germline mutations in persons from distinct undiagnosed VHL families.

Somatic mutations inVHL germline deletion kindred correlate with mild phenotype

Generally, von Hippel-Lindau (VHL) disease is caused by a germline mutation of the VHL gene (chromosome 3p), and tumorigenesis is initiated from a "second-hit" deletion. A subset of VHL patients have a germline deletion of the VHL gene, and the molecular events leading to tumorigenesis are not fully understood. To determine the molecular pathogenesis of tumor formation in this setting, we analyzed five central nervous system hemangioblastomas from three patients of a single VHL germline deletion kindred, all displaying mild clinical phenotype. Rather than loss of heterozygosity (the "second hit" in VHL germline mutation patients), all tumors from this kindred showed "second-hit" point mutations on the wild-type allele. Moreover, in two patients who each had two hemangioblastomas resected each tumor contained a unique mutation. The specific germline deletion and the overall genetic makeup of the patient did not predict these random "second-hit" point mutations. These results suggest that in patients with germline deletion of a tumor suppressor gene there is a unique genetic mechanism underlying tumorigenesis. This unique genetic mechanism correlates with and may help to understand the mild clinical phenotype seen in these patients.

von Hippel-Lindau disease

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.