The outcome of patients with renal cell carcinoma is limited by the development of metastasis after nephrectomy. To evaluate the genetic basis underlying metastatic progression of human renal cell carcinoma in vivo, we performed a comparative genomic hybridization analysis in 32 clear-cell renal-cell carcinoma metastases. The most common losses involved chromosomes 3p (25%), 4q (28%), 6q (28%), 8p (31%), and 9p (47%). The most common gains were detected at 17q (31%) and Xq (28%). There was one high-level gene amplification at chromosome 11q22-23. The mean number of aberrations in lymph node (4.8 +/- 2.8) and lung metastases (6.2 +/- 4.0) was lower than in other hematogenous metastases (11.5 +/- 8.7, P < 0.05), suggesting that hematogenous dissemination is linked to an acquisition of complex genomic alterations. As genetic differences between primary tumors and metastases give information on genetic changes that have contributed to the metastatic process, relative DNA sequence copy number changes in 19 matched tumor pairs were compared. Genomic changes, which frequently occurred in metastases but not in the corresponding primary tumor were losses of 8p and 9p and gains of 17q and Xq. An abnormal function of genes in these regions may contribute to the metastatic process. According to a statistical analysis of shared genetic changes in matched tumor pairs, a high probability of a common clonal progenitor was found in 11 of 19 patients (58%). Six metastases (32%) were genetically almost completely different from the primary, suggesting that detection of genomic alterations in primary tumors gives only a restricted view of the biological properties of metastatic renal cell carcinoma.

(29,30). MGF binding activity is regulated in vivo and in vitro. High levels were found in nuclear extracts derived from mammary cells of lactating mice and in HC11 cells induced with lactogenic hormones. The regulation of the DNA binding activity of MGF is at least in part due to its state of phosphorylation (30,31).The introduction of mutations into the promoter sequence and gene transfer into HC11 cells revealed the presence of additional regulatory elements in the 1-casein gene promoter. A negatively acting element was found in the region adjacent to the MGF binding site. This element located between -110 and -150 seems to be constituted by two interacting half sites. Mutations in the distal half site (-135 to -145) or in the proximal half site (-110 to -120) by themselves had little effect on the rate of transcription. The simultaneous mutations of both sites resulted in a high level of hormone-independent transcription. Two specific DNAprotein complexes were formed when DNA from this region was used as a probe in band shift experiments. These complexes were down-regulated in extracts of induced cells.These observations led us to propose that one mechanism by which hormones regulate ,-casein transcription is the relief of repression (29).We have further investigated the DNA-protein complexes formed by this promoter region and found that a novel nuclear factor binds to the proximal half of the negative 128 on March 24, 2019 by guest

In sexual-assault cases, autosomal DNA analysis of gynecological swabs is a challenge, as the presence of a large quantity of female material may prevent detection of the male DNA. A solution to this problem is differential DNA extraction, but there is no established best practice for this. We decided to test the efficacy of a number of different protocols on simulated casework samples. Four difficult samples were sent to the nine Swiss laboratories active in forensic genetics. In each laboratory, staff used their routine protocols to separate the epithelial-cell fraction, enriched with the non-sperm DNA, from the sperm fraction. DNA extracts were then sent to the organizing laboratory for analysis. Estimates of male:female DNA ratio without differential DNA extraction ranged from 1:38 to 1:339, depending on the semen used to prepare the samples. After differential DNA extraction, most of the ratios ranged from 1:12 to 9:1, allowing detection of the male DNA. Compared with direct DNA extraction, cell separation resulted in losses of 94-98% of the male DNA. As expected, more male DNA was generally present in the sperm than in the epithelial-cell fraction. However, for about 30% of the samples, the reverse trend was seen. The recovery of male and female DNA was highly variable, depending on the laboratory involved. An experimental design similar to the one used in this study may be of assistance for local protocol testing and improvement.

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