DNA Methylation Profiling of Human Hepatocarcinogenesis

BACKGROUND AND AIMS

Mutations in TERT (telomerase reverse transcriptase) promoter are established gatekeepers in early hepatocarcinogenesis, but little is known about other molecular alterations driving this process. Epigenetic deregulation is a critical event in early malignancies. Thus, we aimed to (1) analyze DNA methylation changes during the transition from preneoplastic lesions to early HCC (eHCC) and identify candidate epigenetic gatekeepers, and to (2) assess the prognostic potential of methylation changes in cirrhotic tissue.

APPROACH AND RESULTS

Methylome profiling was performed using Illumina HumanMethylation450 (485,000 cytosine-phosphateguanine, 96% of known cytosine-phosphateguanine islands), with data available for a total of 390 samples: 16 healthy liver, 139 cirrhotic tissue, 8 dysplastic nodules, and 227 HCC samples, including 40 eHCC below 2cm. A phylo-epigenetic tree derived from the Euclidean distances between differentially DNA-methylated sites (n = 421,997) revealed a gradient of methylation changes spanning healthy liver, cirrhotic tissue, dysplastic nodules, and HCC with closest proximity of dysplasia to HCC. Focusing on promoter regions, we identified epigenetic gatekeeper candidates with an increasing proportion of hypermethylated samples (beta value > 0.5) from cirrhotic tissue (<1%), to dysplastic nodules (≥25%), to eHCC (≥50%), and confirmed inverse correlation between DNA methylation and gene expression for TSPYL5 (testis-specific Y-encoded-like protein 5), KCNA3 (potassium voltage-gated channel, shaker-related subfamily, member 3), LDHB (lactate dehydrogenase B), and SPINT2 (serine peptidase inhibitor, Kunitz type 2) (all P < 0.001). Unsupervised clustering of genome-wide methylation profiles of cirrhotic tissue identified two clusters, M1 and M2, with 42% and 58% of patients, respectively, which correlates with survival (P < 0.05), independent of etiology.

CONCLUSIONS

Genome-wide DNA-methylation profiles accurately discriminate the different histological stages of human hepatocarcinogenesis. We report on epigenetic gatekeepers in the transition between dysplastic nodules and eHCC. DNA-methylation changes in cirrhotic tissue correlate with clinical outcomes.

High Cysteinyl Leukotriene Receptor 1 Expression Correlates with Poor Survival of Uveal Melanoma Patients and Cognate Antagonist Drugs Modulate the Growth, Cancer Secretome, and Metabolism of Uveal Melanoma Cells

Metastatic uveal melanoma (UM) is a rare, but often lethal, form of ocular cancer arising from melanocytes within the uveal tract. UM has a high propensity to spread hematogenously to the liver, with up to 50% of patients developing liver metastases. Unfortunately, once liver metastasis occurs, patient prognosis is extremely poor with as few as 8% of patients surviving beyond two years. There are no standard-of-care therapies available for the treatment of metastatic UM, hence it is a clinical area of urgent unmet need. Here, the clinical relevance and therapeutic potential of cysteinyl leukotriene receptors (CysLT1 and CysLT2) in UM was evaluated. High expression of CYSLTR1 or CYSLTR2 transcripts is significantly associated with poor disease-free survival and poor overall survival in UM patients. Digital pathology analysis identified that high expression of CysLT1 in primary UM is associated with reduced disease-specific survival (p = 0.012; HR 2.76; 95% CI 1.21-6.3) and overall survival (p = 0.011; HR 1.46; 95% CI 0.67-3.17). High CysLT1 expression shows a statistically significant (p = 0.041) correlation with ciliary body involvement, a poor prognostic indicator in UM. Small molecule drugs targeting CysLT1 were vastly superior at exerting anti-cancer phenotypes in UM cell lines and zebrafish xenografts than drugs targeting CysLT2. Quininib, a selective CysLT1 antagonist, significantly inhibits survival (p < 0.0001), long-term proliferation (p < 0.0001), and oxidative phosphorylation (p < 0.001), but not glycolysis, in primary and metastatic UM cell lines. Quininib exerts opposing effects on the secretion of inflammatory markers in primary versus metastatic UM cell lines. Quininib significantly downregulated IL-2 and IL-6 in Mel285 cells (p < 0.05) but significantly upregulated IL-10, IL-1β, IL-2 (p < 0.0001), IL-13, IL-8 (p < 0.001), IL-12p70 and IL-6 (p < 0.05) in OMM2.5 cells. Finally, quininib significantly inhibits tumour growth in orthotopic zebrafish xenograft models of UM. These preclinical data suggest that antagonism of CysLT1, but not CysLT2, may be of therapeutic interest in the treatment of UM.

Predictors of short- and long-term recurrence of suicidal behavior in borderline personality disorder

OBJECTIVE

To evaluate the incidence of suicidal outcomes and risk factors for short- and long-term recurrence of suicidal behavior (SB) among high-risk borderline personality disorder (BPD) patients during a 24-month prospective follow-up period.

METHODS

A multicenter prospective cohort study was designed to compare data obtained from 136 patients admitted to the emergency department for current suicidal ideation (SI) or a recent suicide attempt (SA). Subjects were clinically evaluated and monitored for a new SA or suicide.

RESULTS

The incidence of a new SA was 25.63 events/100 persons-year, and one patient died by suicide. Child sexual abuse (CSA) was the only significant predictor throughout the complete follow-up period. The absence of prior psychiatric treatment predicts the recurrence of SB in the first 6 months of follow-up. Patient age, poor psychosocial functioning before hospitalization, age at first SA, and having multiple suicide attempts increased risk of SB recurrence at the long-term period (24th months). In addition, there was an interaction between CSA and poor psychosocial functioning that increased risk of SB.

CONCLUSION

The risk of recurrence was higher during the first 6 months. Risk factors at 6 and 24 months vary. These findings are important for implementing suicide strategies.

Abstract 474: Genome-wide DNA methylation profiling reveals novel candidate epigenetic gatekeepers in hepatocarcinogenesis

Epigenetic deregulation is a critical event in human malignancies. Besides mutations in TERT promoter, found in 20% of dysplastic nodules, little is known about the key molecular alterations driving early hepatocarcinogenesis. The aims of this study were: 1) to analyze DNA methylation changes during the transition from preneoplastic lesions to early hepatocellular carcinoma (HCC), and 2) to identify candidate epigenetic gatekeepers in the transition between dysplasia and early tumors.

Methylome profiling was done with Illumina HumanMethylation450 (485,000 CpG, 96% of known CpG islands). We evaluated differentially methylated CpG sites between groups using an F-test. To detect novel epigenetic gatekeepers we defined hypermethylation as a B value higher than 0.5. We profiled 144 fresh-frozen tissues from resection or liver transplant specimens and integrated these data with our previously report on DNA methylation in HCC (Villanueva et al. Hepatology 2015) resulting in: 16 normal liver, 139 cirrhosis, 8 dysplastic nodules and 227 HCC samples. Correlation between methylation and RNA expression (n= 361) was quantified with the Pearson’s coefficient.

Patients were mostly male (76%), with a median age of 66, and with underlying liver disease mainly due to hepatitis C (43%) and B (23%). All tumors were early stage according to BCLC classification, including 43 cases below 2 cm in diameter. A phylo-epigenetic tree derived from the euclidean distances between differentially DNA methylated sites (n=421,997) reveals a gradient of methylation changes that spans normal, cirrhotic, dysplastic nodules and HCC. Epigenetic analysis confirmed closer proximity of dysplasia to HCC than to cirrhotic tissue. We validated aberrant methylation of previously reported HCC epidrivers within the unpublished dataset (e.g. EFBN2, TBX15) (Villanueva et al. Hepatology 2015). Focusing on CpG sites located in promoter regions (i.e., TSS200, TSS1500, 5’UTR, and 1st exon), we selected candidates hypermethylated in less than 1% of normal and cirrhotic tissue, in all high grade dysplastic nodules, and in more than 50% of small HCC nodules (&lt;2 cm). When we integrated DNA methylation and gene expression we found a significant (all P&lt;0.001) inverse correlation in TSPYL5 (r=-0.31), KCNA3 (r=-0.33), LDBH (r=-0.46) and SPINT2 (r=-0.43).

Whole-genome DNA methylation profiles accurately discriminate between different histological lesions along the human hepatocarcinogenesis spectrum. We report novel epigenetic gatekeepers in the transition between dysplastic nodules and early HCC.

Citation Format: Gabriela Hernandez Meza, Johann von Felden, Amanda Craig, Sergi Sayols, Anna Portela, Manel Esteller, Myron Schwartz, Vincenzo Mazzaferro, Josep Llovet, Augusto Villanueva. Genome-wide DNA methylation profiling reveals novel candidate epigenetic gatekeepers in hepatocarcinogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 474.

IGF2 Is Up-regulated by Epigenetic Mechanisms in Hepatocellular Carcinomas and Is an Actionable Oncogene Product in Experimental Models

BACKGROUND & AIMS

Effective treatments are urgently needed for hepatocellular carcinoma (HCC), which is usually diagnosed at advanced stages. Signaling via the insulin-like growth factor (IGF) pathway is aberrantly activated in HCC by IGF2 overexpression. We aimed to elucidate the mechanism of IGF2 overexpression and its oncogenic activities and evaluate the anti-tumor effects of reducing IGF2 signaling.

METHODS

We obtained 228 HCC samples from patients who underwent liver resection, 168 paired non-tumor adjacent cirrhotic liver samples, and 10 non-tumor liver tissues from patients undergoing resection for hepatic hemangioma. We analyzed gene expression, microRNA, and DNA methylation profiles for all samples, focusing on genes in the IGF signaling pathway. IGF2 was expressed in SNU449 and PLC5 HCC cells and knocked down with small hairpin RNAs in Hep3B and Huh7 cell lines. We analyzed these cells for proliferation, apoptosis, migration, and colony formation. We performed studies in mice engineered to express Myc and Akt1 in liver, which develop liver tumors, with or without hepatic expression of Igf2. Mice with xenograft tumors grown from HCC cells were given a monoclonal antibody against IGF1 and IGF2 (xentuzumab), along with sorafenib; tumor growth was measured and tissues were analyzed by immunohistochemistry and immunoblots.

RESULTS

Levels of IGF2 messenger RNA and protein were increased >20-fold in 15% of human HCC tissues compared with non-tumor liver tissues. Methylation at the fetal promoters of IGF2 was reduced in the HCC samples and cell lines that overexpressed IGF2, compared with those that did not overexpress this gene, and non-tumor tissues. Tumors that overexpressed IGF2 had gene expression patterns significantly associated with hepatic progenitor cell features, stellate cell activation, NOTCH signaling, and an aggressive phenotype (P < .0001). In mice engineered to express Myc and Akt1 in liver, co-expression of Igf2 accelerated formation of liver tumors, compared to mice with livers expressing only Myc and Akt1, and shortened survival times (P = .02). The antibody xentuzumab blocked phosphorylation of IGF1 receptor in HCC cell lines and reduced their proliferation and colony formation. In mice with xenograft tumors, injection of xentuzumab, with or without sorafenib, slowed tumor growth and increased survival times compared to vehicle or sorafenib alone. Xentuzumab inhibited phosphorylation of IGF1 receptor and AKT and reduced decreased tumor vascularization compared with vehicle.

CONCLUSIONS

A large proportion of HCC samples were found to overexpress IGF2, via demethylation of its fetal promoter. Overexpression of IGF2 accelerates formation of liver tumors in mice with hepatic expression of MYC and AKT1, via activation of IGF1 receptor signaling. An antibody against IGF1 and IGF2 slows growth of xenograft tumors and increases survival of these mice.

Abstract 3820: Epigenetic re-expression of fetal IGF2 as therapeutic target in hepatocellular carcinoma

Background and aims

Hepatocellular carcinoma (HCC) is a major health problem. Most patients are diagnosed at advanced stages when the only approved therapy is the multi-kinase inhibitor sorafenib. Consequently, there is a great need for the development of new effective treatments. IGF signaling pathway is aberrantly activated in HCC; however, its contribution to HCC pathogenesis is still unclear. Since IGF2 is overexpressed in HCC, we aimed to elucidate the oncogenic potential and mechanism of dis-regulation of this protein and determine the antitumoral efficacy of molecular abrogation of this ligand by targeted therapies.

Methods

Transcriptomic profiling, miRNAs expression, RNA- and whole exome- sequencing and methylation were analyzed in 228 HCCs with a focus on IGF-pathway. Gene Set Enrichment Analysis and Ingenuity Pathway Analysis were carried out in IGF2-overexpressing tumors. Stable HCC cell lines with knock-down and ectopic overexpression of IGF2 were generated. A chemically-induced mouse model of HCC, and two genetically-engineered mosaic mouse models (GEMM) overexpressing IGF2 specifically in the liver were generated to assess IGF2 oncogenicity in hepatocarcinogenesis. The therapeutic potential of a monoclonal-antibody against IGF-ligands (IGF1/2-mAb) alone or in combination with sorafenib was tested in a xenograft model of HCC.

Results

Here, IGF2-overexpression occurred in 15% of HCC patients as a result of the epigenetic reactivation of IGF2-fetal promoters, mainly through loss of promoters methylation (53% of cases) and deregulation of miR-216b, miR-483-5p and miR-let7-d (35% of cases). Re-expression of IGF2 was associated with a progenitor cell-like, poorly differentiated and aggressive subtype of HCC, and poor prognosis (p&lt;0.0001). In a GEMM model, IGF2-overexpression accelerated HCC progression and reduced survival (p = 0.02). Conversely, IGF2-blockage using an IGF1/2-monoclonal antibody (mAb) or specific shRNAs against IGF2 reduced viability and proliferation in vitro (p&lt;0.05), and inhibited IGF-Insulin pathway activation without disturbing insulin metabolism. IGF1/2-mAb delayed tumor growth and increased survival in vivo compared to placebo or sorafenib (p&lt;0.0001), through antiproliferative and antiangiogenic mechanisms.

Conclusions

IGF2 is the first validated epidriver in HCC and has a key role in the hepatocarcinogenic process. These results provide the rationale for testing IGF1/2-mAb in a selected subset of HCC patients.

Citation Format: Iris Martinez-Quetglas, Roser Pinyol, Daniel Dauch, Sara Torrecilla, Victoria Tovar, Agrin Moeini, Clara Alsinet, Anna Portela, Augusto Villanueva, Manel Esteller, Lars Zender, Josep M Llovet. Epigenetic re-expression of fetal IGF2 as therapeutic target in hepatocellular carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3820.

Epigenetic activation of a cryptic TBC1D16 transcript enhances melanoma progression by targeting EGFR

Metastasis is responsible for most cancer-related deaths, and, among common tumor types, melanoma is one with great potential to metastasize. Here we study the contribution of epigenetic changes to the dissemination process by analyzing the changes that occur at the DNA methylation level between primary cancer cells and metastases. We found a hypomethylation event that reactivates a cryptic transcript of the Rab GTPase activating protein TBC1D16 (TBC1D16-47 kDa; referred to hereafter as TBC1D16-47KD) to be a characteristic feature of the metastatic cascade. This short isoform of TBC1D16 exacerbates melanoma growth and metastasis both in vitro and in vivo. By combining immunoprecipitation and mass spectrometry, we identified RAB5C as a new TBC1D16 target and showed that it regulates EGFR in melanoma cells. We also found that epigenetic reactivation of TBC1D16-47KD is associated with poor clinical outcome in melanoma, while conferring greater sensitivity to BRAF and MEK inhibitors.

DNA methylation-based prognosis and epidrivers in hepatocellular carcinoma

Epigenetic deregulation has emerged as a driver in human malignancies. There is no clear understanding of the epigenetic alterations in hepatocellular carcinoma (HCC) and of the potential role of DNA methylation markers as prognostic biomarkers. Analysis of tumor tissue from 304 patients with HCC treated with surgical resection allowed us to generate a methylation-based prognostic signature using a training-validation scheme. Methylome profiling was done with the Illumina HumanMethylation450 array (Illumina, Inc., San Diego, CA), which covers 96% of known cytosine-phosphate-guanine (CpG) islands and 485,000 CpG, and transcriptome profiling was performed with Affymetrix Human Genome U219 Plate (Affymetrix, Inc., Santa Clara, CA) and miRNA Chip 2.0. Random survival forests enabled us to generate a methylation signature based on 36 methylation probes. We computed a risk score of mortality for each individual that accurately discriminated patient survival both in the training (221 patients; 47% hepatitis C-related HCC) and validation sets (n = 83; 47% alcohol-related HCC). This signature correlated with known predictors of poor outcome and retained independent prognostic capacity of survival along with multinodularity and platelet count. The subset of patients identified by this signature was enriched in the molecular subclass of proliferation with progenitor cell features. The study confirmed a high prevalence of genes known to be deregulated by aberrant methylation in HCC (e.g., Ras association [RalGDS/AF-6] domain family member 1, insulin-like growth factor 2, and adenomatous polyposis coli) and other solid tumors (e.g., NOTCH3) and describes potential candidate epidrivers (e.g., septin 9 and ephrin B2).

CONCLUSIONS

A validated signature of 36 DNA methylation markers accurately predicts poor survival in patients with HCC. Patients with this methylation profile harbor messenger RNA-based signatures indicating tumors with progenitor cell features.

Regulation of pri-miRNA processing by a long noncoding RNA transcribed from an ultraconserved region

Noncoding RNAs (ncRNAs) control cellular programs by affecting protein-coding genes, but evidence increasingly points to their involvement in a network of ncRNA-ncRNA interactions. Here, we show that a long ncRNA, Uc.283+A, controls pri-miRNA processing. Regulation requires complementarity between the lower stem region of the pri-miR-195 transcript and an ultraconserved sequence in Uc.283+A, which prevents pri-miRNA cleavage by Drosha. Mutation of the site in either RNA molecule uncouples regulation in vivo and in vitro. We propose a model in which lower-stem strand invasion by Uc.283+A impairs microprocessor recognition and efficient pri-miRNA cropping. In addition to identifying a case of RNA-directed regulation of miRNA biogenesis, our study reveals regulatory networks involving different ncRNA classes of importance in cancer.

DNA methylation determines nucleosome occupancy in the 5'-CpG islands of tumor suppressor genes

Promoter CpG island hypermethylation of tumor suppressor genes is an epigenetic hallmark of human cancer commonly associated with nucleosome occupancy and the transcriptional silencing of the neighboring gene. Nucleosomes can determine the underlying DNA methylation status. Herein, we show that the opposite is also true: DNA methylation can determine nucleosome positioning. Using a cancer model and digital nucleosome positioning techniques, we demonstrate that the induction of DNA hypomethylation events by genetic (DNMT1/DNMT3B deficient cells) or drug (a DNA demethylating agent) approaches is associated with the eviction of nucleosomes from previously hypermethylated CpG islands of tumor suppressor genes. Most importantly, the establishment of a stable cell line that restores DNMT1/DNMT3B deficiency shows that nucleosomes reoccupy their positions in de novo methylated CpG islands. Finally, we extend these results to the genomic level, combining a DNA methylation microarray and the nucleosome positioning technique. Using this global approach, we observe the dependency of nucleosome occupancy upon the DNA methylation status. Thus, our results suggest that there is a close association between hypermethylated CpG islands and the presence of nucleosomes, such that each of these epigenetic mechanisms can determine the recruitment of the other.

Exploiting tumor vulnerabilities: epigenetics, cancer metabolism and the mTOR pathway in the era of personalized medicine

Patient stratification according to drug responses, together with the discovery of novel antitumor targets, is leading to a new era of personalized cancer treatments. With the aim of identifying emerging pathways and the challenges faced by clinicians during clinical trials, the IDIBELL Cancer Conference on Personalized Cancer Medicine took place in Barcelona on December 3-4, 2012. This conference brought together speakers working in different areas of cancer research (epigenetics, metabolism and the mTOR pathway, cell death and the immune system, clinical oncology) to discuss the latest developments in personalized cancer medicine.

Bivalent histone modifications in stem cells poise miRNA loci for CpG island hypermethylation in human cancer

It has been proposed that the existence of stem cell epigenetic patterns confer a greater likelihood of CpG island hypermethylation on tumor suppressor-coding genes in cancer. The suggested mechanism is based on the Polycomb-mediated methylation of K27 of histone H3 and the recruitment of DNA methyltransferases on the promoters of tumor suppressor genes in cancer cells, when those genes are preferentially pre-marked in embryonic stem cells (ESCs) with bivalent chromatin domains. On the other hand, miRNAs appear to be dysregulated in cancer, with many studies reporting silencing of miRNA genes due to aberrant hypermethylation of their promoter regions. We wondered whether a pre-existing histone modification profile in stem cells might also contribute to the DNA methylation-associated silencing of miRNA genes in cancer. To address this, we examined a group of tumor suppressor miRNA genes previously reported to become hypermethylated and inactivated specifically in cancer cells. We analyzed the epigenetic events that take place along their promoters in human embryonic stem cells and in transformed cells. Our results suggest that there is a positive correlation between the existence of bivalent chromatin domains on miRNA promoters in ESCs and the hypermethylation of those genes in cancer, leading us to conclude that this epigenetic mark could be a mechanism that prepares miRNA promoters for further DNA hypermethylation in human tumors.

Regulation of SNAIL1 and E-cadherin function by DNMT1 in a DNA methylation-independent context

Mammalian DNA methyltransferase 1 (DNMT1) is essential for maintaining DNA methylation patterns after cell division. Disruption of DNMT1 catalytic activity results in whole genome cytosine demethylation of CpG dinucleotides, promoting severe dysfunctions in somatic cells and during embryonic development. While these observations indicate that DNMT1-dependent DNA methylation is required for proper cell function, the possibility that DNMT1 has a role independent of its catalytic activity is a matter of controversy. Here, we provide evidence that DNMT1 can support cell functions that do not require the C-terminal catalytic domain. We report that PCNA and DMAP1 domains in the N-terminal region of DNMT1 are sufficient to modulate E-cadherin expression in the absence of noticeable changes in DNA methylation patterns in the gene promoters involved. Changes in E-cadherin expression are directly associated with regulation of β-catenin-dependent transcription. Present evidence suggests that the DNMT1 acts on E-cadherin expression through its direct interaction with the E-cadherin transcriptional repressor SNAIL1.

Epigenetic modifications and human disease

Epigenetics is one of the most rapidly expanding fields in biology. The recent characterization of a human DNA methylome at single nucleotide resolution, the discovery of the CpG island shores, the finding of new histone variants and modifications, and the unveiling of genome-wide nucleosome positioning maps highlight the accelerating speed of discovery over the past two years. Increasing interest in epigenetics has been accompanied by technological breakthroughs that now make it possible to undertake large-scale epigenomic studies. These allow the mapping of epigenetic marks, such as DNA methylation, histone modifications and nucleosome positioning, which are critical for regulating gene and noncoding RNA expression. In turn, we are learning how aberrant placement of these epigenetic marks and mutations in the epigenetic machinery is involved in disease. Thus, a comprehensive understanding of epigenetic mechanisms, their interactions and alterations in health and disease, has become a priority in biomedical research.

Do intrauterine growth restriction and overweight at primary school age increase the risk of elevated body mass index in young adults?

Obesity is one of the rising public health problems characterized as a risk factor for many chronic diseases in adulthood. Early life events such as intrauterine growth restriction, as well as life style, are associated with an increased prevalence of this disease. The present study was performed to determine if intrauterine growth restriction interacts with overweight at primary school age to affect body mass index (BMI) in young adults. From June 1, 1978 to May 31, 1979, 6827 singleton liveborns from Ribeirão Preto, São Paulo State, Brazil, corresponding to 98% of all births at the 8 maternity hospitals, were examined and their mothers were interviewed. Samples from the initial cohort were examined again at primary school age (8 to 11 years of age) and at the time of military service (18 years of age). There were 519 male individuals with complete measurements taken in the three surveys. Intrauterine growth-restricted individuals had a BMI 0.68 kg/m(2) lower than that of individuals who were not restricted (95%CI = -1.34 to -0.03) and overweight at primary school age showed a positive and strong effect on BMI at 18 years of age (coefficient 5.03, 95%CI = 4.27 to 5.79). However, the increase in BMI was much higher--6.90 kg/m(2)--when the conscript had been born with intrauterine growth restriction and presented overweight at primary school age (95%CI = 4.55 to 9.26). These findings indicate that the effect of intrauterine growth restriction on BMI at 18 years of age is modified by later weight gain during school age.

Molecular and bioinformatic analysis of the FB-NOF transposable element

The Drosophila melanogaster transposable element FB-NOF is known to play a role in genome plasticity through the generation of all sort of genomic rearrangements. Moreover, several insertional mutants due to FB mobilizations have been reported. Its structure and sequence, however, have been poorly studied mainly as a consequence of the long, complex and repetitive sequence of FB inverted repeats. This repetitive region is composed of several 154 bp blocks, each with five almost identical repeats. In this paper, we report the sequencing process of 2 kb long FB inverted repeats of a complete FB-NOF element, with high precision and reliability. This achievement has been possible using a new map of the FB repetitive region, which identifies unambiguously each repeat with new features that can be used as landmarks. With this new vision of the element, a list of FB-NOF in the D. melanogaster genomic clones has been done, improving previous works that used only bioinformatic algorithms. The availability of many FB and FB-NOF sequences allowed an analysis of the FB insertion sequences that showed no sequence specificity, but a preference for A/T rich sequences. The position of NOF into FB is also studied, revealing that it is always located after a second repeat in a random block. With the results of this analysis, we propose a model of transposition in which NOF jumps from FB to FB, using an unidentified transposase enzyme that should specifically recognize the second repeat end of the FB blocks.

An FB-NOF mediated duplication of the white gene is responsible for the zeste1 phenotype in some Drosophila melanogaster unstable strains

The males of the Drosophila melanogaster M115 mutant strain and of its spontaneous revertant strain RM115 are phenotypically similar to those carrying the w(+UZ) and w(+UR) alleles. The molecular description of these mutant strains could be extended to the unstable-zeste system, which has been used as a genotoxicity test, and could be of use for a better understanding of the assay. An FB element in the 3' vicinity of the white gene, actually into the second intron of the newly predicted CG32795 gene, was found and precisely located in our M115 and RM115 strains, and also in w(+UZ) as expected. We demonstrate the presence of NOF sequences in the M115 and w(+UZ) insertions. However, we found that the z1 phenotype in these males might not be due to the FB-NOF interference on the zeste-white interaction but to a duplication of the white gene unnoticed in previous studies. The reversion of RM115 correlates with the loss of the duplication, probably by a complex recombination event. Furthermore, a FISH experiment suggests that the two copies of white are nearby or tandemly duplicated.

Global priority setting for Cochrane systematic reviews of health promotion and public health research

BACKGROUND

Systematic reviews of health promotion and public health interventions are increasingly being conducted to assist public policy decision making. Many intra-country initiatives have been established to conduct systematic reviews in their relevant public health areas. The Cochrane Collaboration, an international organisation established to conduct and publish systematic reviews of healthcare interventions, is committed to high quality reviews that are regularly updated, published electronically, and meeting the needs of the consumers.

AIMS

To identify global priorities for Cochrane systematic reviews of public health topics.

METHODS

Systematic reviews of public health interventions were identified and mapped against global health risks. Global health organisations were engaged and nominated policy-urgent titles, evidence based selection criteria were applied to set priorities.

RESULTS

26 priority systematic review titles were identified, addressing interventions such as community building activities, pre-natal and early infancy psychosocial outcomes, and improving the nutrition status of refugee and displaced populations.

DISCUSSION

The 26 priority titles provide an opportunity for potential reviewers and indeed, the Cochrane Collaboration as a whole, to address the previously unmet needs of global health policy and research agencies.

Empowerment of women, men, families and communities: true partners for improving maternal and newborn health

Based on the Health Promotion approach, the Making Pregnancy Safer initiative has proposed a strategic framework for working with individuals, families and communities to improve maternal and newborn health. The aims are to contribute to the empowerment of women, families and communities to increase their influence and control over maternal and newborn health, as well as to increase access to and utilization of quality skilled care. The framework has identified those strategies and interventions that target the factors known to contribute to health inequalities and poor maternal and newborn health. While empowerment is an aim of the framework, it is also considered a means. Emphasis is placed on the processes and the quality of the processes rather than just on the actions themselves. The authors in this paper would like to contribute to ongoing discussions about the 'how' of working with women, men, families and communities for improved maternal and newborn health.

Influenza A virus NEP (NS2 protein) downregulates RNA synthesis of model template RNAs

The influenza A virus NEP (NS2) protein is an structural component of the viral particle. To investigate whether this protein has an effect on viral RNA synthesis, we examined the expression of an influenza A virus-like chloramphenicol acetyltransferase (CAT) RNA in cells synthesizing the four influenza A virus core proteins (nucleoprotein, PB1, PB2, and PA) and NEP from recombinant plasmids. Influenza A virus NEP inhibited drastically, and in a dose-dependent manner, the level of CAT expression mediated by the recombinant influenza A virus polymerase. This inhibitory effect was not observed in an analogous artificial system in which expression of a synthetic CAT RNA is mediated by the core proteins of an influenza B virus. This result ruled out the possibility that inhibition of reporter gene expression was due to a general toxic effect induced by NEP. Analysis of the virus-specific RNA species that accumulated in cells expressing the type A recombinant core proteins and NEP showed that there was an important reduction in the levels of minireplicon-derived vRNA, cRNA, and mRNA molecules. Taken together, the results obtained suggest a regulatory role for NEP during virus-specific RNA synthesis, and this finding is discussed regarding the biological implications for the virus life cycle.

Remission of heart failure through endoluminal repair of femoral arteriovenous fistula with the use of a covered stent

We report the case of a 21-year-old male with high-output heart failure due to a femoral arteriovenous fistula caused by a firearm wound. A new balloon expandable stent covered with polytetrafluorethylene was implanted in the artery to occlude the arteriovenous fistula. The fistula was immediately occluded and the artery remained patent. On the following day, the patient felt much better, with no symptoms of heart failure. Additional follow-up is required to assure the usefulness of this less invasive procedure in the treatment of arteriovenous fistulas.

Influenza virus matrix protein is the major driving force in virus budding

To get insights into the role played by each of the influenza A virus polypeptides in morphogenesis and virus particle assembly, the generation of virus-like particles (VLPs) has been examined in COS-1 cell cultures expressing, from recombinant plasmids, different combinations of the viral structural proteins. The presence of VLPs was examined biochemically, following centrifugation of the supernatants collected from transfected cells through sucrose cushions and immunoblotting, and by electron-microscopic analysis. It is demonstrated that the matrix (M1) protein is the only viral component which is essential for VLP formation and that the viral ribonucleoproteins are not required for virus particle formation. It is also shown that the M1 protein, when expressed alone, assembles into virus-like budding particles, which are released in the culture medium, and that the recombinant M1 protein accumulates intracellularly, forming tubular structures. All these results are discussed with regard to the roles played by the virus polypeptides during virus assembly.

Rescue of synthetic RNAs into thogoto and influenza A virus particles using core proteins purified from Thogoto virus

The ribonucleoprotein (RNP) complexes of Thogoto virus (THOV), a tick-borne orthomyxovirus, have been purified from detergent-lysed virions. The purified RNPs were then disrupted by centrifugation through a CsCl-glycerol gradient to obtain fractions highly enriched in nucleoprotein (NP) and virtually devoid of viral genomic RNA. When these NP-enriched fractions were incubated with a synthetic THOV-like RNA, and the mixtures were transfected into THOV-infected cells, the synthetic RNA was expressed and packaged into THOV particles. Similarly, hybrid mixtures containing purified THOV NP and influenza A virus synthetic RNAs (either a model CAT RNA or a gene encoding the viral neuraminidase), were prepared and transfected into influenza A virus-infected cells. The synthetic CAT RNA, was shown to be expressed and packaged into virus particles, and the neuraminidase gene was rescued into influenza virions. These data are discussed in terms of the similarities observed between THOV and influenza A virus and the potential application of the THOV purified proteins for rescuing synthetic genes into infectious viruses.

Several protein regions contribute to determine the nuclear and cytoplasmic localization of the influenza A virus nucleoprotein

A systematic analysis was carried out to identify the amino acid signals that regulate the nucleo-cytoplasmic transport of the influenza A virus nucleoprotein (NP). The analysis involved determining the intracellular localization of eight deleted recombinant NP proteins and 14 chimeric proteins containing the green fluorescent protein fused to different NP fragments. In addition, the subcellular distribution of NP derivatives that contained specific substitutions at serine-3, which is the major phosphorylation site of the A/Victoria/3/75 NP, were analysed. From the results obtained, it is concluded that the NP contains three signals involved in nuclear accumulation and two regions that cause cytoplasmic accumulation of the fusion proteins. One of the karyophilic signals was located at the N terminus of the protein, and the data obtained suggest that the functionality of this signal can be modified by phosphorylation at serine-3. These findings are discussed in the context of the transport of influenza virus ribonucleoprotein complexes into and out of the nucleus.

Efficient formation of influenza virus-like particles: dependence on the expression levels of viral proteins

It has previously been demonstrated in this laboratory that an influenza virus-like chloramphenicol acetyltransferase (CAT) RNA could be expressed in COS-1 cells that synthesized all ten influenza A virus-encoded proteins from recombinant plasmids. It was also shown that supernatant fluids harvested from these cultures contained virus-like particles (VLPs) that could deliver an enclosed CAT RNA to MDCK cells. Here, it is shown that the levels of expression of the reporter gene in the COS-1 and/or MDCK cells can be altered drastically by modifying the concentrations of the recombinant plasmids transfected in the COS-1 cells. Thus, it was observed that overexpression of NS2 reduced CAT expression in COS-1 cells, whereas overexpression of M2 and NS1 proteins dramatically decreased transmission of the CAT RNA to the MDCK cultures. These results are discussed with reference to the roles of these proteins during virus replication. From these experiments, a ratio of transfected plasmids was found that increased the efficiency of the previously described system by 50-100-fold. Under these optimized conditions, it was demonstrated that VLPs can be formed in the absence of neuraminidase expression and that these VLPs remained aggregated to each other and to cell membranes. Moreover, it is shown that CAT RNA transmission was dependent on specific interactions of the ribonucleoprotein complex with other viral structural polypeptides. These data demonstrate the usefulness of this encapsidation-packaging system for the study of different aspects of the influenza virus life-cycle.

Mutational analysis of influenza A virus nucleoprotein: identification of mutations that affect RNA replication

The influenza A virus nucleoprotein (NP) is a multifunctional polypeptide which plays a pivotal role in virus replication. To get information on the domains and specific residues involved in the different NP activities, we describe here the preparation and characterization of 20 influenza A virus mutant NPs. The mutations, mostly single-amino-acid substitutions, were introduced in a cDNA copy of the A/Victoria/3/75 NP gene and, in most cases, affected residues located in regions that were highly conserved across the NPs of influenza A, B, and C viruses. The mutant NPs were characterized (i) in vivo (cell culture) by analyzing their intracellular localization and their functionality in replication, transcription, and expression of model RNA templates; and (ii) in vitro by analyzing their RNA-binding and sedimentation properties. The results obtained allowed us to identify both a mutant protein that accumulated in the cytoplasm and mutations that altered the functionality and/or the oligomerization state of the NP polypeptide. Among the mutations that reduced the NP capability to express chloramphenicol acetyltransferase protein from a model viral RNA (vRNA) template, some displayed a temperature-sensitive phenotype. Interestingly, four mutant NPs, which showed a reduced functionality in synthesizing cRNA molecules from a vRNA template, were fully competent to reconstitute complementary ribonucleoproteins (cRNPs) capable of synthesizing vRNAs, which in turn yielded mRNA molecules. Based on the phenotype of these mutants and on previously published observations, it is proposed that these mutant NPs have a reduced capability to interact with the polymerase complex and that this NP-polymerase interaction is responsible for making vRNPs switch from mRNA to cRNA synthesis.

In vivo reconstitution of active Thogoto virus polymerase: assays for the compatibility with other orthomyxovirus core proteins and template RNAs

Tick-borne Thogoto virus (THOV), the prototype of a new genus in the Orthomyxoviridae family, contains six single-stranded RNA segments of negative polarity. Four of them encode gene products that correspond to the influenza virus PB1, PB2, PA and NP core proteins. Here we describe an in vivo system in which the expression of a THOV model RNA is driven by THOV core proteins synthesized from cloned cDNAs. Our results demonstrated the biological activity of our cloned genes and showed that the three polymerase subunits and the NP are required for gene expression. For comparison, we also used the in vivo reconstituted systems of the influenza A and B viruses. None of the polymerase or NP proteins was active in a heterologous orthomyxovirus core, indicating a high specificity in core assembly and/or function. Interestingly, the THOV polymerase did not recognize the influenza A virus promoter and vice versa.

[Coronary intervention at a general hospital in the State of Piauí, Brazil]

PURPOSE

To evaluate retrospectively success and complication rates of coronary interventions performed in a general hospital with no digital equipment in the State of Piauí with a small annual number of procedures.

METHODS

From August/91 to January/98, 122 patients underwent 146 procedures using a fluoroscope with camera and TV monitor of 525 lines. The variables analyzed included the initial success of procedures (residual stenosis less than fifty percent and TIMI III flow) and more serious complications (acute occlusion, infarcts, emergency surgeries and death). The clinical data and the morphological characteristics of the lesions (ACC/AHA Task Force) were also analyzed.

RESULTS

Eighty five percent of the patients presented with an acute ischemic syndrome (acute myocardial infarction, post infarction angina, rest angina), 5% were in cardiogenic shock and 88% had type B lesions. The initial success rate was 93% while the more serious complications occurred in 3.5% of the cases.

CONCLUSION

In spite of the small annual procedural volume and the use of conventional equipment, the initial success rate in our institution was excellent in a diverse and complex patient population while the complication rates were similar to that of the literature.

The three subunits of the polymerase and the nucleoprotein of influenza B virus are the minimum set of viral proteins required for expression of a model RNA template

The genes encoding the nucleoprotein, PB1, PB2, and PA proteins of the influenza virus strain B/Panamá/45/90 have been cloned under control of the T7 RNA polymerase promoter of plasmid pGEM-3. Transfection of the recombinant plasmids obtained into mammalian cells, which had been infected with a vaccinia virus encoding the T7 RNA polymerase, resulted in expression of the expected influenza B virus polypeptides. Moreover, it is shown that coexpression of the four recombinant core proteins in COS-1 cells reconstituted a functional polymerase capable of expressing a synthetic influenza B virus-like CAT RNA. By using the influenza B virus recombinant plasmids and a set of pGEM-derived plasmids encoding the homologous core proteins of the influenza A virus A/Victoria/3/75 (I. Mena et al. (1994). J. Gen. Virol. 75, 2109-2114), the capabilities of homo- and heterotypic mixtures of the four core proteins to express synthetic type A and B CAT RNAs were analyzed. Both the influenza A and B virus polymerases were active in expressing, albeit with reduced efficiencies, the heterotypic model CAT RNAs. However, none of all possible heterotypic mixtures of the core proteins reconstituted a functional polymerase. In order to fully characterize the recombinant plasmids obtained, the nucleotide sequences of the cloned genes were determined and compared to sequences of other type B virus isolates. The results obtained from these latter analyses are discussed in terms of the conservation and evolution of the influenza B virus core genes.

The 5' ends of Thogoto virus (Orthomyxoviridae) mRNAs are homogeneous in both length and sequence

Thogoto (THO) virus is a tick-borne member of the Orthomyxoviridae whose genome consists of six segments of linear, negative sense, single-stranded RNA. To gain insight into the mechanism by which viral mRNA transcripts are initiated, poly(A)+ RNA isolated from THO virus-infected cells was characterized by (i) primer extension experiments, (ii) immunoprecipitation studies with an anticap monoclonal antibody, (iii) direct sequencing analysis of the isolated RNA, and (iv) cloning and sequencing of individual mRNA molecules. The results indicated that THO virus mRNAs are capped and homogeneous in both length and sequence at their 5' end. These findings contrast with the situation found in all other segmented, negative sense or ambisense, single-stranded RNA viruses so far analyzed in which the 5' ends of viral mRNAs are heterogeneous in length and sequence. These results are discussed in terms of the mechanism used by THO virus to initiate mRNA synthesis.

Changes in human blood pressure with season, age and solar cycles: a 26 year record

The record was studied of a 71-year-old, diurnally active (0700-2200 hours) male psychiatrist (G.N.) who self-measured systolic and diastolic blood pressure (BPS and BPD) mostly but not exclusively on Sunday mornings, from 1969 to 1994. A large about-yearly change was revealed which increased with age and was accompanied by a decreasing trend in the yearly rhythm-adjusted mean (MESOR; P < 0.01). According to conventional criteria that specify only upper limits of acceptability, G.N. was hypertensive in summer and normotensive in other seasons. Since changes in both MESOR and circannual amplitude occurred, a systematic surveillance of BP is the chronobiological recommendation.

Clinical relevance of about-yearly changes in blood pressure and the environment

Changes identified by inferential statistics from summer to winter of high to low arterial blood pressures (BP) have been quantified as a large predictable about-yearly BP swing. This condition of a large annual BP amplitude (LABPA) raises concern about hypotension as well as hypertension and raises new questions regarding appropriate guidelines for diagnosis and treatment. Recommendations made in the fall on the basis of data collected in the summer may be totally inadequate in dealing with the patient's condition in the winter. In order to avoid such mistakes, it is imperative to implement a systematic surveillance of BP in the light of current chronobiological limits. Patients with a large circannual BP amplitude are particularly suited for a study of the underlying hormonal mechanisms. The longitudinal monitoring of their BP is also amenable to the study of environmental influences from near and far.

The circadian rhythm of cortisol in the saliva of young pigs

Single and population-mean cosinor analyses document a circadian rhythm in salivary cortisol of pigs (p < 0.001). The midline estimated statistic of rhythm, the MESOR (M), is 1.50 +/- 0.07 ng/ml. For the group of 14 pigs studied there was a predictable variation of 64% around this mean in salivary cortisol within a day: the double circadian amplitude, 2A, was 0.96 ng/ml, with a 95% confidence interval ranging from 0.60 to 1.32 ng/ml. A measure of timing, the acrophase, phi, was 10 h 52 min from the phase reference (0030, the middle of the daily dark span of the 24-h light-dark cycle in which the pigs were kept). The 95% confidence interval of phi extended from 9 h 48 min to 12 h 12 min from the reference time. The chronobiologic approach provides indispensable quantitive characteristics as reference standards for future basic or applied work.

Rescue of a synthetic chloramphenicol acetyltransferase RNA into influenza virus-like particles obtained from recombinant plasmids

We have shown previously that COS-1 cells infected with a vaccinia virus recombinant (vTF7-3) which expresses the T7 RNA polymerase gene and then transfected with four pGEM-derived plasmids encoding the influenza A virus core proteins (nucleoprotein, PB1, PB2, and PA polypeptides) can express a synthetic influenza virus-like chloramphenicol [correction of chloramphenical] acetyltransferase (CAT) RNA (I. Mena, S. de la Luna, C. Albo, J. Martín, A. Nieto, J. Ortín, and A. Portela, J. Gen. Virol. 75:2109-2114, 1994). Here we demonstrate that by supplying the vTF7-3-infected cells with plasmids containing cDNAs of all 10 influenza virus-encoded proteins, the transfected CAT RNA can be expressed and rescued into particles that are budded into the supernatant fluids. The released particles can transfer the enclosed CAT RNA to MDCK cultures and resemble true influenza virions in that they require trypsin treatment to deliver the RNA to fresh cells and are neutralized by a monoclonal antibody specific for the influenza A virus hemagglutinin. Moreover, analysis by electron microscopy showed that the culture medium harvested from the transfected cells contained vesicles that could be labeled with an anti-HA monoclonal antibody and that were similar in size and morphology to authentic influenza virus particles. It is also shown that detection of recombinant particles capable of transmitting the CAT RNA does not require expression of the influenza virus nonstructural protein NS1. All of these data indicate that influenza virus-like particles enclosing a synthetic virus-like RNA can be assembled in cells expressing all viral structural components from recombinant plasmids.

[Chronobiology in medicine and surgery]

Chronobiology studies predictable variations, rhythms and trends in all forms of life. Each physiologic variable or system in an organism has a time structure which is genetically anchored and capable of being expressed in the absence of external cycles. However, it is normally adjusted by geophysical changes. Chronobiology quantifies rhythms by providing measures of amplitude and timing (phase and period), and a mean more precise than the arithmetic mean. The correct measurement of biological rhythms has led to considerable advances in the understanding of their underlying mechanisms of generation and expression. The use of information on rhythms is opening new opportunities in the prevention, diagnosis and treatment of disease. Chronobiology is also effective in the improvement of the quality of life by teaching self-help to the healthy individual.

Serine 3 is critical for phosphorylation at the N-terminal end of the nucleoprotein of influenza virus A/Victoria/3/75

The influenza A virus nucleoprotein (NP) is a phosphoprotein that encapsidates the viral genomic RNA. To map the in vivo phosphorylation site(s) of this protein, 32P-labeled NP was purified from cell cultures infected with influenza virus A/Victoria/3/75 by immunoaffinity chromatography. The purified protein was then subjected to chemical digestion with formic acid, which cleaves proteins at Asp-Pro bonds, and the resulting products were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two of the phosphorylated products obtained were identified as fragments corresponding to the N-terminal 88 amino acids and to the C-terminal 196 residues of the NP. To identify the phosphate acceptor site(s) at the N-terminal phosphorylated region of NP, each of the seven serines within this region was individually changed to alanine by site-directed mutagenesis. The mutant proteins were then transiently expressed in mammalian cells and analyzed for their phosphorylation state. It was observed that the S-to-A mutation at position 3 drastically reduced the amount of 32P label incorporated into NP, whereas the other substitutions did not have a discernible effect on the phosphorylation level of the protein. In addition, all serine-altered proteins were tested for their functionality in an artificial system in which expression of a synthetic chloramphenicol acetyl-transferase RNA molecule is driven by influenza virus proteins synthesized from cloned genes. The results obtained demonstrate that all mutant proteins were competent to cooperate with the subunits of the viral polymerase for expression of the synthetic virus-like chloramphenicol acetyltransferase RNA in vivo. These data are discussed regarding the possible roles of NP phosphorylation for the viral replicative cycle.

A point mutation in the F1 subunit of human respiratory syncytial virus fusion glycoprotein blocks its cell surface transport at an early stage of the exocytic pathway

Vaccinia virus recombinants expressing either wild-type or mutant forms of human respiratory syncytial (RS) virus (Long strain) fusion (F) glycoprotein were obtained. Proteolytic processing of the precursor, F0, and cell surface transport of the F glycoprotein were unaffected in the recombinants, except in those that contained the replacement Phe --> Ser at position 237 of the F1 subunit. In recombinants containing this mutation, either alone or in combination with others, the traffic of the F molecule was arrested at some intermediate step of its transport to the cell surface and, consequently, the endoproteolytic cleavage of the F0 precursor was inhibited. Immunofluorescence staining of infected cells and endoglycosidase H (Endo-H) sensitivity assays indicated that the arrest occurred before the mid-Golgi compartment. Dimerization and folding of the F protein were also affected by the Phe237 --> Ser substitution. Other amino acid replacements at positions 236 or 237 of the F1 subunit had various effects upon F0 maturation. These results are discussed in terms of the maturation requirements for the RS virus F molecule.

Epitope mapping of cross-reactive monoclonal antibodies specific for the influenza A virus PA and PB2 polypeptides

Characterization of the epitopes recognized by 21 monoclonal antibodies (MAbs) specific for the influenza A virus PA (13 MAbs) and PB2 (8 MAbs) polypeptides (Bárcena et al. (1994) J. Virol. 68, 6900-6909) raised against denatured polypeptides produced in E. coli is described. MAbs were characterized by: (1) competitive binding ELISAs; (2) mapping of the protein regions that specify their binding sites; and (3) analyses of their ability to recognize the corresponding viral protein in a number of viral isolates. Five and three non-overlapping antigenic areas were defined by the anti-PA and anti-PB2 MAbs, respectively. Five of the anti-PA MAbs recognized antigenic determinants located within the amino-terminal 157 amino acids of the PA protein, and 6 others reacted strongly with a PA fragment comprising the first 236 amino acids. All 8 anti-PB2 antibodies reacted strongly with a polypeptide fragment containing amino acids 1-113 of the PB2 protein. Analyses of the reactivities of 4 anti-P antibodies with 23 influenza A virus reference strains isolated over a period of 61 years and recovered from humans, pigs, birds and horses, showed that the epitopes were conserved among all viral isolates. The application of these antibodies as research and diagnostic tools is discussed.

X-irradiation chronosensitivity and circadian rhythmic proliferation in healthy and sarcoma-carrying rats' bone marrow

Mitotic activity of bone marrow and tumor of sarcoma-bearing rats and of bone marrow of healthy controls is circadian periodic. Whereas the circadian rhythm in mitotic activity of bone marrow is similar for intact and tumor-bearing rats, with a peak occurring shortly after the onset of the dark (activity) span, the circadian rhythm in mitotic activity of tumor has a much smaller amplitude and a different acrophase occurring late in the dark span. This difference in acrophase of mitotic activity of bone marrow and tumor has important implications for scheduling the administration of oncotherapy. For the tumor model examined herein, it suggests the possibility to achieve concomitantly near maximal efficacy and near minimal myelotoxicity, a result awaiting further investigation in humans with different kinds of malignancies.

Spectral differences between epitopes in the cronomes of salivary CA130 and CA125

Ovarian tumor markers CA125 and CA130 are here investigated in the search for harbingers of an elevated cancer risk or pre-cancer. A circadian rhythm of large amplitude is demonstrated for salivary CA125 and CA130 of a clinically healthy 28-year-old woman (AP). The circadian rhythms of both markers found in AP have a pattern similar to that of a patient (EH) with a müllerian cancer involving the ovary, with high values in the early morning and low values in the afternoon. Whereas acrophases occur approximately at the same circadian stage in both AP and EH, the MESOR and circadian amplitude are higher in EH as compared to AP. The circadian rhythm of salivary CA130 of AP is similar to that of other clinically healthy women. CA130 concentrations are lower than CA125 concentrations in unstimulated saliva (before rinsing of the mouth) in this clinically healthy woman (AP), and in other women studied herein. This difference between CA130 and CA125 concentrations is observed irrespective of circadian stage and irrespective of the concentration range of CA125 at the outset. After rinsing of the mouth, a statistically significant decrease in both CA130 and CA125 concentration is observed in AP and in another healty woman (GC) who collected saliva both before and after rinsing of the mouth.

Toward a chronome of superfused pike pineals: about-weekly (circaseptan) modulation of circadian melatonin release

In continuous darkness for about 5.5 days in eleven replications, the pineal shows neither only a decreasing trend nor only a damped circadian rhythm; there is an infradian modulation: after an initial decline, melatonin production increases again, with a pattern compatible with the assumption, for at least one cycle, that a built-in pineal "week" has a larger extent of predictable change than that of a pineal "day". Melatonin release from the isolated pike pineal reveals a circadian rhythm which, on the average, is damped, but demonstrable in the second half of a time series covering 5.5 days (P < 0.05). At fixed environmental temperatures of 10, 15, 19 or 20 degrees C (the latter two pooled), single and population mean cosinor analyses reject the assumptions of zero circaseptan and circadian amplitudes in the chronome of the pineal from the pike (Esox lucius L.). The circaseptan pattern is confounded by possible trends. The time series analyzed are brief, yet validate, by a one-way analysis of variance in plexograms as well as by cosinor, an about-weekly pattern, if not (yet) rhythm, on the basis of 745 determinations. The circaseptan- and circasemiseptan-to-circadian amplitude ratios are numerically larger than unity, on the average (2.014; 95% confidence interval, CI: 1.120 to 3.641 and 1.107; CI: 0.724 to 1.693, respectively). A positive correlation of the urinary excretion rate of a major breakdown product of melatonin of a cancer patient with a circulating cancer marker serving as a gauge of disease progression lends an oncologic perspective to the amplitude ratios of melatonin release in vitro here reported.(ABSTRACT TRUNCATED AT 250 WORDS)