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J Schutte

Publications and source records attributed to J Schutte.

6 recordsLinked to original sources

Loss of expression of the DRR 1 gene at chromosomal segment 3p21.1 in renal cell carcinoma.

Consistent deletion of DNA sequences in chromosomal band 3p21 observed in a variety of human tumors suggests the presence of one or more tumor suppressor genes within this region. Previously, we reported on the construction of two distinct cosmid contigs and our identification of several new genes within 3p21.1. In our search for tumor suppressor genes from this region, we have cloned a gene that we have called DRR 1 (downregulated in renal cell carcinoma). The gene was first mapped to 3p21.1 by fluorescence in situ hybridization analysis. Further analysis of yeast artificial chromosome clones in 3p14.2-p21.1 refined its localization. DRR 1 spans about 10 Kb of genomic DNA with a 3.5-Kb mature transcript. The putative protein encoded by this gene is 144 amino acids and includes a nuclear localization signal and a coiled domain. The gene showed loss of expression in eight of eight renal cell carcinoma cell lines, one of seven ovarian cancer cell lines, one of one cervical cancer cell line, one of one gastric cancer cell line, and one of one non-small-cell lung cancer cell line. Southern blot analysis did not show any altered bands, indicating that gross structural changes or deletions did not cause the loss of expression. This gene was also found to have reduced expression in 23 of 34 paired primary renal cell carcinomas. Mutational analysis detected three polymorphic sites within the gene, but no point mutations were identified in the 34 primary tumors. However, we did detect base substitutions in 4 of 12 cell lines that had undetectable expression of the gene. We also transfected the gene into DRR 1-negative cell lines and observed clear growth retardation. Our results suggest that loss of expression of the DRR 1 gene may play an important role in the development of renal cell carcinoma and possibly other tumors. Genes Chromosomes Cancer 27:1-10, 2000.

Amino Acid Sequence↗

Precise localization of aphidicolin-induced breakpoints on the short arm of human chromosome 3.

The common fragile site at 3p14.2 (FRA3B) has been described as the most active fragile site in the human genome. This locus may predispose chromosome 3 to specific losses due to deletions and translocations that have been associated with several malignancies, including hereditary renal cell carcinoma. We have previously described induction of breakage around FRA3B using aphidicolin in a somatic cell hybrid whose only human component was a single intact chromosome 3. That work led to the isolation of hybrids with breakpoints in the 3p13-p21.1 region with loss of all sequences distal to their respective breakpoints. In this report we describe the further characterization of the breakpoints in many of these cell lines using newly available molecular markers. We also report the identification of YAC clones that span the breakpoints present in many of these hybrids.

Aphidicolin↗

Effect of pneumonectomy on the remaining lung in dogs.

To determine the magnitude of functional compensation after pneumonectomy and whether compensation is related to maturity of the animal at the time of resection, we performed left pneumonectomy in either adult or 10-wk-old beagles. Studies were performed in adults 7-9 mo after surgery and in puppies 18-23 mo after surgery when the dogs reached full maturity. Results were compared with those in age- and sex-matched unoperated controls. Measurements included pressure-volume relationships, pulmonary hemodynamics, rebreathing studies of lung volume, diffusing capacity and its components, lung tissue volume, and pulmonary blood flow. Computerized-tomographic scans were performed in the puppy groups to determine changes in thoracic shape and size. Morphometric analysis of the lungs was performed under light microscopy. There was partial compensation for loss of one lung by functional improvement in the remaining lung. Compensation was greater in those pneumonectomized as puppies than as adults. Volume of the remaining lung was larger than predicted for a given transpulmonary pressure in both groups. Diffusing capacity, pulmonary capillary blood volume, and lung tissue volume were larger than expected for the normal right lung. After pneumonectomy, compliance of the rib cage was greater in puppies than in adults. Weight of the costal diaphragm was reduced in pneumonectomized puppies. Pulmonary hypertension at rest did not develop, and pulmonary vascular reactivity to hypoxia was unchanged after pneumonectomy in both groups. Significant correlations were obtained between physiological and morphometric measurements.

Age Factors↗

Review of the clinical trials activity of the Soft Tissue and Bone Sarcoma Group of the European Organization for Research and Treatment of Cancer.

Despite the low incidence of sarcomas, the Soft Tissue and Bone Sarcoma Group has established itself as one of the more active cooperative groups of the European Organization for Research and Treatment of Cancer. Performing over a 10 yr period three phase III protocols (total entry 750 patients), three randomized phase II studies (464 patients), a pilot combination study (185 patients), and 12 phase II studies (406 patients). The new randomized phase III protocol for advanced soft-tissue sarcoma will provide an interesting test of the validity of the current membership policy, which has not discouraged the participation of enthusiastic new members. For extremity sarcomas, improved surgical techniques have increased the number of patients retaining functional limbs but have maintained excellent rates of local control. However, systemic metastasis remains a significant problem and presents a challenge for future adjuvant studies.

Adult↗

Interactions between surface cooling and LBNP-induced central hypovolemia.

The interaction between whole body surface cooling (WBSC) and progressive lower body negative pressure (LBNP) to -50 torr was evaluated in nine healthy male volunteers, mean age 29 +/- 1.7 years. WBSC, accomplished by circulating 16 degrees C water through an Apollo cooling garment, produced a significant drop in mean skin temperature of 1.96 degrees C (p less than 0.001). Cardiac output (Q) was measured by the C2H2 rebreathing technique. Changes in leg volume (LgV) were monitored by a Whitney strain gauge. WBSC at rest produced a significant decrease in leg volume of 0.27 I (p less than 0.01). Heart rate decreased (-7 bpm, p less than 0.01) and systolic arterial blood pressure was increased (+6 torr, p less than 0.02). The hemodynamic effects of cooling were maintained throughout progressive levels of LBNP with consistently lower leg volumes and heart rates and higher stroke volumes and systolic pressure (p less than 0.01 for all measurements). The data suggest that WBSC produces a central displacement of cutaneous venous volume resulting in an increase in stroke volume.

Adult↗