Early-stage epithelial ovarian cancer: an overview

The clinical treatment of malignant epithelial ovarian cancer limited to the gonad(s) involves many problems that have given rise to analyses in recent literature and to different approaches: i. intensive anatomo-radio-surgical staging, evaluation and clinical incidence of prognostic risk factors; ii. re-staging of patients after inadequate and incomplete surgery; iii. indications, role and topicality of second-look surgery; iv. conservative surgery in patients of a fertile age wishing to have children and retain activity of the gonads; v. laparoscopic surgery for treatment, staging, re-staging and surveillance; vi. the lymph node issue; vii. adjuvant therapy: indications, options, type of drugs, doses and length; viii. quality and frequency of surveillance; ix. malignant epithelial ovarian cancer limited to the gonads in pregnancy. The clinical handling of these tumours entails many complex problems causing emotional involvement since it is most frequent at a fertile age.

Microsatellite instability and frameshift mutations in genes involved in cell cycle progression or apoptosis in ovarian cancer

The loss of mismatch repair enzymes increases the mutation rate in microsatellites and coding regions of the genome and appears to be involved in drug resistance. The replication error (RER+) phenotype, associated with microsatellite instability, has been widely described for both familial and sporadic colon cancers and for gastric and endometrial tumors. For ovarian cancer, the incidence of RER+ cases among sporadic tumors is still uncertain. We analyzed epithelial ovarian tumors and ovarian carcinoma cell lines for microsatellite instability and for mutations in the coding regions of different genes, including the recently discovered human CHK-1 gene, which has an important role in controlling cell cycle progression and whose coding region contains a poly(A)9 tract. Microsatellite instability and frameshift mutations in coding regions of BAX, TGFbetaRII, IGFIIR, E2F-4, ICE, and CHK-1 genes were analyzed in ovarian cancer samples and cell lines by polymerase chain reaction (PCR). Approximately 26% of patients showed microsatellite instability in two or more loci. BAT-26 locus showed no alteration in primary tumors. We detected a BAX mutation in one tumor sample and a TGFbetaRII mutation in one cell line. Our findings confirm the presence of the RER+ phenotype in sporadic ovarian cancer. The low rate of mutation in genes previously reported to be altered in colon and gastric cancer suggests that other not yet identified genes might be altered and could play a role in tumor progression and response to treatment in RER+ ovarian tumors.

Evidence for a different sensitivity to various central effects of interleukin-1 beta in mice

Interleukin 1 (IL-1) induces a series of metabolic and endocrine effects. Activation of the hypothalamus-pituitary-adrenal axis, inhibition of food and water intake, elevation of serum interleukin-6 (IL-6) concentration and hypoglycemia are some of the effects induced by IL-1. The purpose of this study was to compare the sensitivity of these effects following central and peripheral administration of IL-1 beta. Different doses of IL-1 beta (0.1-1000 ng/mouse) were centrally (ICV) or peripherally (IP) injected to male mice two hours prior to sacrifice. The ICV administration was more efficacious than the IP injection in elevating serum corticosterone and IL-6 concentrations, whereas no difference was evident in the IL-1 beta-induced hypoglycemia. Central IL-1 beta administration was also more potent than IP injection in inhibiting overnight food and water intake. A dose-dependent effect was evident in all these cases. In summary, our data compare effects elicited by central or peripheral administration of different doses of IL-1 beta. This comparison suggests that the IL-1 beta stimulation of serum corticosterone and IL-6 and inhibition of food and water intake are events more centrally mediated than the IL-1 beta-induced hypoglycemia.

Studies on glucose-induced inactivation of gluconeogenetic enzymes in adenylate cyclase and cAMP-dependent protein kinase yeast mutants

Glucose-induced inactivation of the gluconeogenetic enzymes fructose-1,6-biphosphatase, cytoplasmic malate dehydrogenase and phosphoenolpyruvate carboxykinase was tested in yeast mutants defective in adenylate cyclase (cyr1 mutation) and in the cAMP-binding subunit of cAMP-dependent protein kinase (bcy 1 mutation). In the mutant AM7-11D (cyr1 mutation), glucose-induced cAMP overshoot was absent, and no significant inactivation of the gluconeogenetic enzymes was detected, thus supporting the role of cAMP in the process. Moreover, in the mutant AM9-8B (bcy1 mutation), no cAMP-dependent protein kinase activity was evidenced, and, in addition, a normal inactivation pattern was observed, thus indicating that other mechanisms evoked by glucose might be required in the process. In the double mutant AM7-11DR-4 (cyr1 bcy1 mutations), no inactivating effect was triggered by the sugar: this suggests that cAMP exerts some additional effect on the process, besides the activation of cAMP-dependent protein kinase. Furthermore, in AM7-11D, extracellular cAMP triggered about 50% of inactivation of fructose-1,6-bisphosphatase; this effect was largely reversed in acetate medium plus cycloheximide even after 150 min of incubation. However, an extensive and essentially irreversible inactivation was evidenced in the presence of glucose plus cAMP, whereas glucose alone was only slightly effective. Therefore, the reversible effect of cAMP, which probably corresponds to enzyme phosphorylation, seems to be required for the irreversible, probably proteolytic, glucose-stimulated inactivation of this enzyme. Cytoplasmic malate dehydrogenase and phosphoenolpyruvate carboxykinase in AM7-11D were also inactivated by cAMP, and much more by glucose plus cAMP, whereas glucose was practically ineffective. However, reversibility of the effect was not detected, and, in addition, no phosphorylation of phosphoenolpyruvate carboxykinase could be evidenced. Therefore, the sugar quite probably stimulates proteolysis of these enzymes, but the mechanism of cAMP in their degradation has still to be defined.