We have identi®ed parameters which de®ne a causal role of HPV16 in head and neck cancer. Twenty-eight tumours which were typed positive for HPV16 DNA, were comprehensively analysed for expression of the viral oncogenes E6 and E7, the status of the p53 gene, and the protein status of pRb and p16 INK4a. In a subset of cases, we have searched for integrated viral DNA, and have determined the genomic status of the E6 gene. Expression of E6/E7 was found in 12 tumours most of which were derived from the oropharynx, whereas p53 mutations were present in 13 tumours from various sites. The tumours either carried p53 mutations but did not express E6/E7, or they did express E6/E7 but were p53-wild-type. Coexistence of E6/E7 expression with a mutated p53 was found in only one case. Strikingly, in most p53-mutated tumours without E6/E7 expression, we found the E6 gene to be disrupted. E6/E7 expression was associated with reduced pRb and overexpressed p16INK4a . Viral-cellular fusion transcripts were found in two cases. Our data demonstrate that HPV16 DNA-positivity in head and neck cancers is not indicative of a causal role. A causal role of HPV16 in head and neck cancer is de®ned by: E6/E7 expression, viral integration with an intact E6 gene, and perturbation of pRb cell cycle control. Mostly, the p53 gene is wild-type.

In a worldwide collaborative effort, 19,630 Y-chromosomes were sampled from 129 different populations in 51 countries. These chromosomes were typed for 23 short-tandem repeat (STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, GATAH4, DYS481, DYS533, DYS549, DYS570, DYS576, and DYS643) and using the PowerPlex Y23 System (PPY23, Promega Corporation, Madison, WI). Locus-specific allelic spectra of these markers were determined and a consistently high level of allelic diversity was observed. A considerable number of null, duplicate and off-ladder alleles were revealed. Standard single-locus and haplotype-based parameters were calculated and compared between subsets of Y-STR markers established for forensic casework. The PPY23 marker set provides substantially stronger discriminatory power than other available kits but at the same time reveals the same general patterns of population structure as other marker sets. A strong correlation was observed between the number of Y-STRs included in a marker set and some of the forensic parameters under study. Interestingly a weak but consistent trend toward smaller genetic distances resulting from larger numbers of markers became apparent.

Background and Purpose-Serum levels of the cytokine interleukin-6 (IL-6) rise markedly in stroke. IL-6 is a key regulator of inflammatory mechanisms that play an important part in stroke pathophysiology. The action of IL-6 is modified by its soluble receptor subunits sgp130 and sIL-6R. The purpose of this study was to investigate whether serum levels of the receptor subunits are changed after ischemic stroke and to define the role of genetic influences on IL-6 expression in acute stroke. Methods-In 48 patients with acute stroke and 48 age-and sex-matched control subjects, serum concentrations of IL-6, sgp130, and sIL-6R were measured by enzyme-linked immunosorbent assay. Furthermore, IL-6 promoter haplotypes comprising 4 different polymorphisms (Ϫ597G3 A, Ϫ572G3 C, Ϫ373A(n)T(n), Ϫ174G3 C) were determined by DNA sequencing and allele-specific oligonucleotide polymerase chain reaction. The effect of the common haplotypes on IL-6 gene transcription was tested by transfecting reporter fusion genes in the astrocytelike cell line U373. Results-Whereas serum concentrations of IL-6 significantly rose (PϽ0.001), sgp130 levels were transiently reduced after stroke (PϽ0.05), and sIL-6R levels remained unchanged. IL-6 levels depended on the infarct size and the haplotype of the promoter region. The common haplotype A-G-8/12-C was associated with low IL-6 levels after stroke and a reduced induction of IL-6 transcription on stimulation with an adenosine analog in vitro. Conclusions-The data demonstrate genetic variation in the expression of IL-6 in stroke. Induction of the inflammatory response by IL-6 might be enhanced by a transient downregulation of the potential IL-6 antagonist sgp130. (Stroke.

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