We describe a gene, NM23, that is associated with the tumor metastatic process. NM23 RNA levels were highest in cells and tumors of relatively low metastatic potential in two experimental systems: (1) murine K-1735 melanoma cell lines, in which the gene was identified, and (2) N-nitroso-N-methylurea-induced rat mammary carcinomas. NM23 RNA levels did not correlate with cell sensitivity to host immunological responses and may, therefore, be associated with intrinsic aggressiveness. The predicted carboxy-terminal protein sequence encoded by the pNM23 cDNA clone is novel compared with Genebank animal, bacterial, and viral sequences.
Germ cell tumour is the most frequent malignant tumour type in young men with a 100% rise in the incidence every 20 years. Despite this, the high sensitivity of germ cell tumours to platinum-based chemotherapy, together with radiation and surgical measures, leads to the high cure rate of > or = 99% in early stages and 90%, 75-80% and 50% in advanced disease with 'good', 'intermediate' and 'poor' prognostic criteria (IGCCCG classification), respectively. The high cure rate in patients with limited metastatic disease allows the reduction of overall treatment load, and therefore less acute and long-term toxicity, e.g. organ sparing surgery for specific cases, reduced dose and treatment volume of irradiation or substitution of node dissection by surveillance or adjuvant chemotherapy according to the presence or absence of vascular invasion. Thus, different treatment options according to prognostic factors including histology, stage and patient factors and possibilities of the treating centre as well may be used to define the treatment strategy which is definitively chosen for an individual patient. However, this strategy of reduction of treatment load as well as the treatment itself require very high expertise of the treating physician with careful management and follow-up and thorough cooperation by the patient as well to maintain the high rate for cure. Treatment decisions must be based on the available evidence which has been the basis for this consensus guideline delivering a clear proposal for diagnostic and treatment measures in each stage of gonadal and extragonadal germ cell tumour and individual clinical situations. Since this guideline is based on the highest evidence level available today, a deviation from these proposals should be a rare and justified exception.
Whereas the vast majority of the recommendations made in 2004 remain valid 3 yr later, refinements in the treatment of early-stage as well as of advanced-stage testicular cancer have emerged from clinical trials. Despite technical improvements, expert clinical skills will continue to be one of the major determinants for the prognosis of patients with germ cell cancer. In addition, the particular needs of testicular cancer survivors have been acknowledged.
The 2-acetylaminofluorene (AAF)/partial hepatectomy (PH) model is one of the most extensively studied experimental systems for oval cell proliferation and differentiation. We have previously described the oval cells as forming ductular structures surrounded by basement membrane, representing extensions of the canals of Hering. Herein we analyze the differentiation of oval cells into hepatocytes after varying degrees of liver damage induced by AAF. At a low dose of AAF, most oval cells synchronously differentiate into small hepatocytes by 6 days after the PH, resulting in complete restoration of the liver structure in 10 days. Higher doses of AAF delay the differentiation process and the new hepatocytes form foci, in contrast to what is observed at the low dose. Qualitatively, the differentiation process seems to be identical at the cellular level under both conditions. The transition from the expanding oval cell population into hepatocytes was correlated with the upregulation of hepatocyte nuclear factor 4 and the disappearance of the basement membrane. Also, the differentiation of oval cells into hepatocytes coincided with the loss of alpha-fetoprotein and OV-6 staining, and the replacement of the biliary cell-specific ␣6 integrin and connexin 43 with the hepatocyte-specific ␣1 integrin and connexin 32. In addition, bile canaliculi form between the new hepatocytes. In conclusion, these results indicate the rate of oval cell differentiation into hepatocytes is context dependent and suggest that, under favorable conditions, oval cells can complete this process much faster than previously appreciated.
Many undesired side effects or therapeutic failures of drugs are the result of differences or changes in drug metabolism, primarily depending on the levels and activities of cytochrome P450 (P450) enzymes. To assess whether P450 expression profiles can reflect hepatic drug metabolism, we compared P450 mRNA levels in the liver or peripheral leukocytes with the corresponding hepatic P450 activities. A preliminary P450 genotyping for the most frequent polymorphisms in white populations (CYP2C9*2, CYP2C9*3, CYP2C19*2, CYP2C19*3, CYP2D6*3, CYP2D6*4, CYP2D6*6, and CYP3A5*3) was carried out before P450 phenotyping, excluding the donors with nonfunctional alleles of CYP2C9, CYP2C19, and CYP2D6 and those with a functional CYP3A5*1 allele from a correlation analysis. The hepatic mRNA levels of CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 displayed a strong association with P450 activities in the liver, whereas the expression of CYP1A2, CYP2C9, CYP2C19, and CYP3A4 in leukocytes was proven to reflect the hepatic activities of these P450 species. The leukocytes were found to be inappropriate cells for the assessment of hepatic CYP2B6 and CYP2D6 activities. Combining the results of P450 genotyping and phenotyping analyses, patients' drug-metabolizing capacities can be estimated by the P450 expression in the liver and in leukocytes with some limitations. Patients' genetic and nongenetic variations in P450 status can guide the appropriate selection of drugs and the optimal dose, minimizing the risk of harmful side effects and ensuring a successful outcome of drug therapy.
Objective: Human fetuin/a 2 -HS-glycoprotein (AHSG) is a 49 kDa serum and tissue protein which is a natural inhibitor of insulin receptor signaling. We investigated serum AHSG levels during pregnancy and whether the protein is involved in insulin resistance observed in healthy pregnant women and patients with gestational diabetes. Design: One hundred and four healthy pregnant women and 23 of their neonates, 30 patients with gestational diabetes and their neonates and 30 healthy age-matched non-pregnant females as a control group were investigated in a case-control cross-sectional study. Methods: Serum AHSG was determined by radial immunodiffusion. Results: We observed an increase of serum AHSG concentration in the second and third trimesters. Gestational diabetes patients had significantly higher AHSG levels than healthy pregnant women and non-pregnant controls. There was a highly significant positive correlation between serum AHSG concentration and indirect parameters of insulin resistance, i.e. tumor necrosis factor-a (TNF-a), leptin, C-peptide and C-peptide/blood glucose ratio. There was also a negative correlation between maternal AHSG, TNF-a, leptin levels and head circumference, body length and body weight of newborns. Conclusion: AHSG, TNF-a and leptin may contribute to insulin resistance during normal pregnancy and gestational diabetes. AHSG along with these cytokines may also negatively regulate neonatal skeletal development.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.