The 'relics of Joan of Arc': a forensic multidisciplinary analysis.

Archaeological remains can provide concrete cases, making it possible to develop, refine or validate medico-legal techniques. In the case of the so-called 'Joan of Arc's relics' (a group of bone and archaeological remains known as the 'Bottle of Chinon'), 14 specialists analysed the samples such as a cadaver X of carbonised aspect: forensic anthropologist, medical examiners, pathologists, geneticists, radiologist, biochemists, palynologists, zoologist and archaeologist. Materials, methods and results of this study are presented here.

Apoptin-induced apoptosis: potential for antitumor therapy.

Cytotoxic anticancer agents often exert their effect by inducing apoptosis. Many tumors, however, are resistant to chemotherapy. This is due to lack of expression of certain genes essential in mediating the apoptotic signal, such as p53, or to over-expression of apoptosis inhibitors, such as bcl-2 or bcr-abl.

Abnormal kinetics of induction of UV-stimulated recombination in human DNA repair disorders.

Recombination can result in genetic instability, and thus constitutes an important factor in the carcinogenic conversion of mammalian cells. Here we describe the occurrence of UV-stimulated recombination called enhanced recombination (EREC), measured with the use of Herpes Simplex Viruses type 1 mutants. In normal diploid human cells, EREC is induced by UV-C, mitomycin C and ENU, but not by X-ray or MMS.

Induction of ATF3 by ionizing radiation is mediated via a signaling pathway that includes ATM, Nibrin1, stress-induced MAPkinases and ATF-2.

Exposure of human cells to genotoxic agents induces various signaling pathways involved in the execution of stress- and DNA-damage responses. Inappropriate functioning of the DNA-damage response to ionizing radiation (IR) is associated with the human diseases ataxia-telangiectasia (A-T) and Nijmegen Breakage syndrome (NBS). Here, we show that IR efficiently induces Jun/ATF transcription factor activity in normal human diploid fibroblasts, but not in fibroblasts derived from A-T and NBS patients.

Differential expression of tapasin and immunoproteasome subunits in adenovirus type 5- versus type 12-transformed cells.

Adenovirus type 12 (Ad12)-transformed baby rat kidney (BRK) cells are oncogenic in syngeneic immunocompetent rats in contrast to adenovirus type 5 (Ad5)-transformed BRK cells, which are not oncogenic in these animals. A significant factor contributing to the difference in oncogenicity may be the low levels of major histocompatibility complex (MHC) class I membrane expression in Ad12-transformed BRK cells as compared with those in Ad5-transformed BRK cells, which presumably results in escape from killing by cytotoxic T lymphocytes. Here we show that, in addition to the decreased levels of expression of the MHC class I heavy chain and the peptide transporter Tap-2, the expression levels of the chaperone Tapasin and the immunoproteasome components MECL-1, PA28-alpha, and PA28-beta also are much lower in Ad12- than in Ad5-transformed BRK cells.

Mif1: a missing link between the unfolded protein response pathway and ER-associated protein degradation?

Eukaryotic cells have three different mechanisms to deal with the accumulation of unfolded proteins in the endoplasmic reticulum: (1) In cells in which unfolded polypeptides accumulate, translation initiation is inhibited to prevent further accumulation of unfolded proteins. (2) Expression of proteins involved in polypeptide folding is strongly enhanced by a process called the Unfolded Protein Response (UPR). (3) Proteins missing the proper tertiary structure are degraded by the ER-Associated protein Degradation (ERAD) mechanism.

A role for Rad23 proteins in 26S proteasome-dependent protein degradation?

Treatment of cells with genotoxic agents affects protein degradation in both positive and negative ways. Exposure of S. cerevisiae to the alkylating agent MMS resulted in activation of genes that are involved in ubiquitin- and 26S proteasome-dependent protein degradation.

Down-regulation of T-STAR, a growth inhibitory protein, after SV40-mediated immortalization.

Normal human cells can undergo a limited number of divisions, whereas transformed cells may have an extended life span and can give rise to immortal cells. To isolate genes involved in the immortalization process, gene expression in SV40-transformed preimmortal human fibroblasts was compared with expression in SV40-transformed immortalized fibroblasts using an mRNA differential display. We found that the growth-inhibitory protein testis-signal transduction and activation of RNA (T-STAR) a homologue of cell-cycle regulator Sam68, is strongly down-regulated in immortalized cells.

Mdmx stabilizes p53 and Mdm2 via two distinct mechanisms.

The p53 protein maintains genomic integrity through its ability to induce cell cycle arrest or apoptosis in response to various forms of stress. Substantial regulation of p53 activity occurs at the level of protein stability, largely determined by the activity of the Mdm2 protein. Mdm2 targets both p53 and itself for ubiquitylation and subsequent proteasomal degradation by acting as an ubiquitin ligase, a function that needs an intact Mdm2 RING finger.

WT1 proteins: functions in growth and differentiation.

The Wilms' tumor 1 gene (WT1) has been identified as a tumor suppressor gene involved in the etiology of Wilms' tumor. Approximately 10% of all Wilms' tumors carry mutations in the WT1 gene. Alterations in the WT1 gene have also been observed in other tumor types, such as leukemia, mesothelioma and desmoplastic small round cell tumor.

Induction of the SAPK activator MIG-6 by the alkylating agent methyl methanesulfonate.

The alkylating agent methylmethanesulfonate (MMS) activates the c-jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK) and the p38 mitogen-activated protein kinase (p38MAPK) pathways via different mechanisms of action. Activation of p38MAPK by MMS involves the pp125 focal adhesion kinase-related tyrosine kinase RAFTK and the MAPK kinase 3. The way in which MMS can activate JNK/SAPK has not been elucidated.

Aberrant expression of HDMX proteins in tumor cells correlates with wild-type p53.

It has been shown that the Hdmx gene is amplified in a subset of gliomas, but thus far, no data are available on HDMX protein expression in tumor cells. We now report that a significant fraction of tumor cell lines expresses increased HDMX levels compared with normal cells; in general, HDMX expression in these tumor cell lines correlates with the presence of wild-type p53. Analysis of tumor material showed that high HDMX expression is not a result of cell line establishment.

Protein kinase C-alpha is an upstream activator of the IkappaB kinase complex in the TPA signal transduction pathway to NF-kappaB in U2OS cells.

Inactive nuclear factor kappaB (NF-kappaB) complexes are retained in the cytoplasm by binding to inhibitory proteins, such as IkappaBalpha. Various stimuli lead to phosphorylation and subsequent processing of IkappaBalpha in the 26S proteasome and import of the active NF-kappaB transcription factor into the nucleus. In agreement with our previous finding that p90(rsk1) is essential for TPA-induced activation of NF-kappaB in Adenovirus 5E1-transformed Baby Rat Kidney cells, we now report that the MEK/ERK/p90(rsk1) inhibitor U0126 efficiently blocks TPA-induced IkappaBalpha processing in these cells.

cDNA micro array identification of a gene differentially expressed in adenovirus type 5- versus type 12-transformed cells.

Proteins encoded by non-oncogenic adenovirus type 5 and oncogenic adenovirus type 12 differentially affect expression of a number of cellular genes. We have used cDNA micro array analysis to identify a cellular gene that is expressed in Ad12- but not in Ad5-transformed cells. This cellular gene was found to be the gene encoding follistatin-related protein, a TGF-beta inducible gene.

Towards integrating vectors for gene therapy: expression of functional bacteriophage MuA and MuB proteins in mammalian cells.

Bacteriophage Mu has one of the best studied, most efficient and largest transposition machineries of the prokaryotic world. To harness this attractive integration machinery for use in mammalian cells, we cloned the coding sequences of the phage factors MuA and MuB in a eukaryotic expression cassette and fused them to a FLAG epitope and a SV40-derived nuclear localization signal. We demonstrate that these N-terminal extensions were sufficient to target the Mu proteins to the nucleus, while their function in Escherichia coli was not impeded.

Ammonium sulphate precipitation of recombinant adenovirus from culture medium: an easy method to increase the total virus yield.

In the majority of the methods for purifying and concentrating recombinant adenoviruses (rAds) the virus that is associated with the helper cells is harvested, while the virus that is present in the cell-culture medium is discarded. During routine propagation of adenovirus type-5 vectors at optimised conditions we noted that, on average, 47% of the total amount of virus is present in the culture medium. To recover and concentrate these rAds from the medium, we devised a method, which is based on ammonium sulphate ((NH4)2SO4) precipitation.

The chicken anemia virus-derived protein apoptin requires activation of caspases for induction of apoptosis in human tumor cells.

The chicken anemia virus protein Apoptin has been shown to induce apoptosis in a large number of transformed and tumor cell lines, but not in primary cells. Whereas many other apoptotic stimuli (e.g.

Hdmx stabilizes Mdm2 and p53.

The Mdm2 protein is a key regulator of p53 activity and stability. Upon binding, Mdm2 inhibits the transcription regulatory activity of p53 and promotes its rapid degradation. In this study we investigated the effect of the human Mdm2 homologue Hdmx on p53 stability.

Physical interaction between Wilms tumor 1 and p73 proteins modulates their functions.

The WT1 gene, which is heterozygously mutated or deleted in congenital anomaly syndromes and homozygously mutated in about 15% of all Wilms tumors, encodes tissue-specific developmental regulators. Through alternative mRNA splicing, four main WT1 protein isoforms are synthesized. All isoforms can bind to DNA via their zinc fingers, albeit with different affinities and specificities, and thereby modulate the transcriptional activity of their target genes.

The novel MMS-inducible gene Mif1/KIAA0025 is a target of the unfolded protein response pathway.

In a search for genes induced by DNA-damaging agents, we identified two genes that are activated by methyl methanesulfonate (MMS). Expression of both genes is regulated after endoplasmic reticulum (ER) stress via the unfolded protein response (UPR) pathway. The first gene of those identified is the molecular chaperone BiP/GRP78.

EGR-1 enhances tumor growth and modulates the effect of the Wilms' tumor 1 gene products on tumorigenicity.

The Wilms' tumor 1 gene (WT1) encodes a transcription factor of the zinc-finger family and is homozygously mutated or deleted in a subset of Wilms' tumors. Through alternative mRNA splicing, the gene is expressed as four main polypeptides that differ by a stretch of 17 amino acids just N-terminal of the four zinc-fingers and three amino acids between zinc fingers 3 and 4. We have previously shown that expression of the WT1(-/-) isoform, lacking both inserts, increases the tumor growth rate of the adenovirus-transformed baby rat kidney (AdBRK) cell line 7C3H2, whereas expression of the WT1(-/+) isoform, lacking the 17aa insert, strongly suppresses the tumorigenic phenotype.

E1A + cHa-ras transformed rat embryo fibroblast cells are characterized by high and constitutive DNA binding activities of AP-1 dimers with significantly altered composition.

Transcription factors of the AP-1/ATF family, including c-Fos, c-Jun, and ATF-2, play an important role in the regulation of cell proliferation and differentiation, and changes in their levels and/or activities may contribute to oncogenesis. We analyzed the alterations of AP-1/ATF transcription factors upon immortalization and transformation in a panel of cell lines derived from rat embryo fibroblast (REF) cells. The tumorigenic E1A + cHa-ras cells are characterized by high and constitutive DNA binding activities of AP-1, in contrast to nontransformed cells and the E1A cells.