Patrick Anglard

Localization of the von Hippel-Lindau disease gene to a small region of chromosome 3

We studied 25 families with von Hippel-Lindau disease (VHL) to locate VHL more precisely on chromosome 3. We found that VHL was linked to RAF1, confirming previous observations, and to two polymorphic DNA markers, D3S18 and D3S191. Multipoint linkage analysis indicated that the most likely location for VHL was in the interval between RAF1 and D3S18. D3S18 was located at 3p26. Genetic heterogeneity was not detected in this panel of von Hippel-Lindau disease families. The polymorphic markers RAF1, D3S18, and D3S191 should be useful in identifying asymptomatic gene carriers in VHL families and in guiding efforts at gene isolation.

Epidermal growth factor receptor gene analysis in renal cell carcinoma

The epidermal growth factor receptor binds the mitogens epidermal growth factor and transforming growth factor-alpha. Increased expression of the epidermal growth factor receptor has been noted in many types of tumors and is associated with gene amplification in several including epidermoid carcinoma, lung carcinoma, breast carcinoma and glioblastoma. We have recently observed increased expression of the epidermal growth factor receptor messenger RNA in neoplastic tissue relative to normal kidney tissue from patients with renal cell carcinoma. To determine if epidermal growth factor receptor gene amplification was present in renal cell carcinoma, DNA was extracted from renal cell carcinoma cell lines and from normal kidney and renal cell carcinoma tissues derived from radical nephrectomy specimens from thirty patients. DNA was analyzed by Southern blot hybridization. There was no epidermal growth factor receptor gene amplification detected in the renal cell carcinoma samples studied, indicating the increased epidermal growth factor gene expression observed in renal cell carcinoma does not occur through gene amplification. Unlike other tumors with enhanced epidermal growth factor receptor gene expression, amplification of this gene does not appear to be a common feature of renal cell carcinoma.

Isolation and regional localization of a large collection (2,000) of single-copy DNA fragments on human chromosome 3 for mapping and cloning tumor suppressor genes

SummaryA collection of 2,000 lambda phage-carrying human single-copy inserts (> 700 bp) were isolated from two chromosome-3 flow-sorted libraries. The single-copy DNA fragments were first sorted into 3p and 3q locations and about 700 3p fragments were regionally mapped using a deletion mapping panel comprised of two humanhamster and two-human-mouse cell hybrids, each containing a chromosome 3 with different deletions in the short arm. The hybrids were extensively mapped with a set of standard 3p markers physically localized or ordered by linkage. The deletion mapping panel divided the short arm into five distinct subregions (A-E). The 3p fragments were distributed on 3p regions as follows: region A, 26%; B, 31%; C, 4%; D, 4% and E, 35%. We screened 300 single-copy DNA fragments from the distal part of 3p (regions A and B) with ten restriction endonucleases for their ability to detect restriction fragment length polymorphisms (RFLPs). Of these fragments 110 (36%) were found to detect useful RFLPs: 35% detected polymorphisms with frequency of heterozygosity of 40% or higher, and 25% with frequency of 30% or higher. All polymorphisms originated from single loci and most of them were of the base pair substitution type. These RFLP markers make it possible to construct a fine linkage map that will span the distal part of chromosome 3p and encompasses the von Hippel-Lindau disease locus. The large number of single-copy fragments (2,000) spaced every 100–150 kb on chromosome 3 will make a significant contribution to mapping and sequencing the entire chromosome 3. The 300 conserved chromosome 3 probes will increase the existing knowledge of man-mouse homologies.

Loss of Heterozygosity Occurs Centromeric to RB Without Associated Abnormalities in the Retinoblastoma Gene in Tumors from Patients with Metastatic Renal Cell Carcinoma

Tumor suppressor genes have been found to have loss of function in a number of malignancies. This loss of function is believed to contribute to malignant transformation or metastatic spread. In the present study, expression of the retinoblastoma (RB) tumor suppressor gene was examined in cell lines and tumor tissue obtained from primary renal and metastatic sites in patients with metastatic renal cell carcinoma. Three of fifteen (20%) of informative renal carcinoma cell lines had loss of heterozygosity (LOH) in the RB gene (intron 20) detected by polymerase chain reaction analysis. Using restriction fragment length polymorphism (RFLP) analysis, 7 of 22 (32%) informative cell lines had LOH centromeric to the RB gene at the D13S1 locus. No LOH (0 of 7) was seen telomeric to the RB gene at the D13S2 locus. None of the 28 cell lines examined had decreased RB mRNA expression compared with short-term cultures of proximal renal tubular cells. Western blotting demonstrated phosphorylated and unphosphorylated forms of RB protein of expected molecular weight in all 41 cell lines (33 primary and 8 metastatic) examined. Twenty-nine primary cell lines and 6 metastatic cell lines all demonstrated normal immunohistochemical staining. Loss of RB immunohistochemical staining in paraffin-embedded tissue was detected in none of the primary tumors (0 of 30) or metastatic tumors (0 of 12). The absence of abnormalities of RB expression detected in these renal cell carcinomas suggests that abnormalities of the RB gene are not central to malignant transformation or progression in this tumor type; however, another tumor suppressor gene centromeric to the RB locus may be important in renal cell carcinogenesis.

Expression of NM23 in Cell Lines Derived from Patients with Metastatic Renal Cell Carcinoma

Reduced expression of nm23 has been associated with increased metastases and decreased survival in a variety of malignancies. In the present study, the expression of nm23 was examined by Northern and Western blot analyses in a series of cell lines derived from patients with metastatic renal cell carcinoma. Two of twelve (17%) informative cell lines derived from 9 patients had loss of heterozygosity at Nm23-H1. Twenty-two renal cancer cell lines derived from primary tumors, 5 cell lines derived from metastatic tumors and 4 short-term cultures of normal proximal renal tubular cells all expressed Nm23 mRNA in varying amounts. On average, the level of expression of Nm23 mRNA in short-term cultures of benign proximal renal tubular cells was found to be similar to the level seen in renal cancer cell lines. Twenty-eight cell lines derived from renal primary tumors and 8 cell lines derived from metastatic tumors expressed both the Nm23-H1 and Nm23-H2 proteins. High or low relative expression of nm23 at the mRNA or protein level did not correlate with survival. The absence of any anomalous pattern of expression of the nm23 genes and the lack of correlation of expression with survival suggests that nm23 does not play a central role in the progression of this tumor type.

Studies of the Endocrine and Paracrine Effect of Tumor Produced Factors in Human Genitourinary Cancers

Both prostate as well as kidney cancer are common malignancies in the United States. It is projected that in 1990, prostate carcinoma will be the most common cancer in men and will result in 20,000 deaths. Although hormonal manipulation is the mainstay of therapy of patients with advanced prostate carcinoma, there is no currently available effective therapy for patients with this malignancy. Over 20,000 patients develop kidney cancer per year in the United States, and there are over 9,500 deaths from this cancer. Recent studies have reported approximately a 95%, 5 year survival for patients with Stage T1, No renal cell carcinoma and a 92% survival for patients with Stage T2, No disease (1,2). While the five year survival for patients with N + (local nodal involvement) renal cell carcinoma is 20% (3,4), patients with distant renal cell carcinoma metastases have only a 20% five year survival (5).