Tests of competency to consent to treatment

The authors describe the various tests of competency to consent to treatment used today, which include the following: 1)evidencing a choice, 2)"reasonable" outcome of choice, 3)choice based on "rational" reasons, 4)ability to understand, and 5)actual understanding. They analyze the applicability of these tests to patients' decisions to accept or refuse psychiatric treatment and illustrate the problems of ap-lying these tests by citing clinical case examples. They find that the circumstances in which competency becomes an issue determine which elements of which tests are stressed and which are underplayed.

Respiratory chain inhibition induces tolerance to focal cerebral ischemia

The authors show that the inhibitor of the succinate dehydrogenase, 3-nitroproprionic acid (3-NPA), which in high doses and with chronic administration is a neurotoxin, can induce profound tolerance to focal cerebral ischemia in the rat when administered in a single dose (20 mg/kg) 3 days before ischemia. Infarcts were approximately 70% and 35% smaller in the 3-NPA preconditioned groups of permanent and transient focal cerebral ischemia, respectively. This regimen of 3-NPA preconditioning neither induced necrosis, apoptosis, or any other histologically detectable damage to the brain, nor did it affect behavior of the animals. 3-NPA led to an immediate (1-hour) and long-lasting (3-day) decrease in succinate dehydrogenase activity (30% reduction) throughout the brain, whereas only a short metabolic impairment occurred (ATP decrease of 35% within 30 minutes, recovery within 2 hours). The authors found that 3-NPA induces a burst of reactive oxygen species and the free radical scavenger dimethylthiourea, when administered shortly before the 3-NPA stimulus, completely blocked preconditioning. Inhibition of protein synthesis with cycloheximide given at the time of 3-NPA administration completely inhibited preconditioning. The authors were unsuccessful in showing upregulation of mRNA for the manganese superoxide dismutase, and did not detect increased activities of the copper-zinc and manganese superoxide dismutases, prototypical oxygen free radicals scavenging enzymes, after 3-NPA preconditioning. The authors conclude that it is possible to pharmacologically precondition the brain against focal cerebral ischemia, a strategy that may in principal have clinical relevance. The data show the relevance of protein synthesis for tolerance, and suggests that oxygen free radicals may be critical signals in preconditioning.

Induction of tolerance in rat cortical neurons: hypoxic preconditioning

Sublethal ischemia leads to increased tolerance against subsequent prolonged cerebral ischemia in vivo. In the present study we modeled preconditioning mechanisms in a neuronal-enriched culture. Damage was significantly reduced (up to 72%) with 1.5 h of oxygen-glucose deprivation 48-72 h before 3 h oxygen-glucose deprivation. Tolerance was also elicited by Na+-K+-ATPase inhibition. No damage was observed when astroglial or endothelial cells were exposed to hypoxia for 3 and 6 h, respectively. We conclude that hypoxic preconditioning is a robust neuronal phenomenon in vitro with a similar temporal pattern and selective cellular vulnerability as the ischemic tolerance phenomenon shown in vivo.

Type III restriction enzymes need two inversely oriented recognition sites for DNA cleavage

Type III restriction/modification enzyme recognize short, non-palindromic sequences that can be methylated on only one strand, with the paradoxical consequence that during replication of what is in effect hemimethylated DNA totally unmodified sites arise. Why the unmodified sites are not subject to suicidal restriction was not clear. Here we show that restriction requires two unmodified recognition sites that can be separated by different distances but which must be in inverse orientation. All of the unmodified sites in newly replicated DNA are of course in the same orientation, which explains why they are not restricted. This result may be of relevance to other manifestations of anisotropy in double-stranded DNA, such as genetic imprinting.

Seven legal barriers to end-of-life care: myths, realities, and grains of truth

OBJECTIVE

The American College of Physicians-American Society of Internal Medicine (ACP-ASIM) End-of-Life Care Consensus Panel was convened in 1997 to identify clinical, ethical, and policy problems in end-of-life care, to analyze critically the available evidence and guidelines, and to offer consensus recommendations on how to improve care of the dying. Topic selection and content presentation were carefully debated to maximize the project's focus on providing practical clinical and other guidance to clinicians who are not specialists in palliative care. This statement examines current legal myths, realities, and grains of truth in end-of-life care.

PARTICIPANTS

The Consensus Panel comprises 13 medical and bioethics experts, clinicians, and educators in care at the end of life selected by the Ethics and Human Rights Committee, College leadership, and the Center for Ethics and Professionalism at the ACP-ASIM.

EVIDENCE

A literature review including a MEDLINE search of articles from 1970-1998 and review of end-of-life care literature and organizational bibliographies was conducted. Unpublished sources were also identified by participants, as was anecdotal clinical experience.

CONSENSUS PROCESS

The draft statement was debated by panel members over a series of 3 to 4 meetings. For this statement, the initial draft and subsequent revised drafts were discussed in 1998-1999. The statement then underwent external peer review and revision before panel approval and the journal peer review process.

CONCLUSIONS

Legal myths about end-of-life care can undermine good care and ethical medical practice. In addition, at times ethics, clinical judgment, and the law conflict. Patients (or families) and physicians can find themselves considering clinical actions that are ethically appropriate, but raise legal concerns. The 7 major legal myths regarding end-of-life care are: (1) forgoing life-sustaining treatment for patients without decision-making capacity requires evidence that this was the patient's actual wish; (2) withholding or withdrawing of artificial fluids and nutrition from terminally ill or permanently unconscious patients is illegal; (3) risk management personnel must be consulted before life-sustaining medical treatment may be terminated; (4) advance directives must comply with specific forms, are not transferable between states, and govern all future treatment decisions; oral advance directives are unenforceable; (5) if a physician prescribes or administers high doses of medication to relieve pain or other discomfort in a terminally ill patient, resulting in death, he/she will be criminally prosecuted; (6) when a terminally ill patient's suffering is overwhelming despite palliative care, and he/she requests a hastened death, there are no legally permissible options to ease suffering; and (7) the 1997 Supreme Court decisions outlawed physician-assisted suicide. Many legal barriers to end-of-life care are more mythical than real, but sometimes there is a grain of truth. Physicians must know the law of the state in which they practice. JAMA. 2000;284:2495-2501.

Treatment landscape of metastatic pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive form of cancer with a dismal prognosis. The lack of symptoms in the early phase of the disease makes early diagnosis challenging, and about 80-85% of the patients are diagnosed only after the disease is locally advanced or metastatic. The current front-line treatment landscape in local stages comprises surgical resection and adjuvant chemotherapy. In Switzerland, although both FOLFIRINOX and gemcitabine plus nab-paclitaxel regimens are feasible and comparable in the first-line setting, FOLFIRINOX is preferred in the treatment of fit (Eastern Cooperative Oncology Group [ECOG] performance status [PS]: 0-1), young (<65 years old) patients with few comorbidities and normal liver function, while gemcitabine plus nab-paclitaxel is used to treat less fit (ECOG PS: 1-2) and more vulnerable patients. In the second-line setting of advanced PDAC, there is currently only one approved regimen, based on the phase III NAPOLI-1 trial. Furthermore, the use of liposomal-irinotecan in the second line is supported by real-world data. Beyond the standard of care, various alternative treatment modalities are being explored in clinical studies. Immunotherapy has demonstrated only limited benefits until now, and only in cases of high microsatellite instability (MSI-H). However, data on the benefit of poly (ADP-ribose) polymerase (PARP) inhibition as maintenance therapy in patients with germline BRCA-mutated tumors might signal of an advance in targeted therapy. Currently, there is a lack of molecular and genetic biomarkers for optimal stratification of patients and in guiding treatment decisions. Thus, identification of predictive and prognostic biomarkers and evaluating novel treatment strategies are equally relevant for improving the prognosis of metastatic pancreatic cancer patients.

Toward a model of the legal doctrine of informed consent

The authors draw together the disparate scholarly and judicial commentaries on consent to medical treatment to develop a model of the components in the decision-making process regarding consent to or refusal of psychiatric treatment. The components consist of the precondition of voluntariness, the provision of information, the patient's competency and understanding, and, finally, consent or refusal. They offer two models of valid consent: the objective model, which focuses on the congruence or lack of it between the patient and a "reasonable" person, and the subjective model, which focuses entirely on the patient's actual understanding.

Type III restriction endonucleases translocate DNA in a reaction driven by recognition site-specific ATP hydrolysis

Type III restriction/modification systems recognize short non-palindromic sequences, only one strand of which can be methylated. Replication of type III-modified DNA produces completely unmethylated recognition sites which, according to classical mechanisms of restriction, should be signals for restriction. We have shown previously that suicidal restriction by the type III enzyme EcoP15I is prevented if all the unmodified sites are in the same orientation: restriction by EcoP15I requires a pair of unmethylated, inversely oriented recognition sites. We have now addressed the molecular mechanism of site orientation-specific DNA restriction. EcoP15I is demonstrated to possess an intrinsic ATPase activity, the potential driving force of DNA translocation. The ATPase activity is uniquely recognition site-specific, but EcoP15I-modified sites also support the reaction. EcoP15I DNA restriction patterns are shown to be predetermined by the enzyme-to-site ratio, in that site-saturating enzyme levels elicit cleavage exclusively between the closest pair of head-to-head oriented sites. DNA restriction is blocked by Lac repressor bound in the intervening sequence between the two EcoP15I sites. These results rule out DNA looping and strongly suggest that cleavage is triggered by the close proximity of two convergently tracking EcoP15I-DNA complexes.

Barriers to informed consent

The law of informed consent seeks to actively involve patients in decision making. Most authorities agree that this involvement has not occurred but disagree about why. Some suggest that patients are incapable of understanding medical issues and others that physicians have not explained issues clearly or extensively enough. We observed decision making in several hospital settings and found other significant barriers to patient participation. These barriers include the fact that treatment decisions take place over a long period; there are often many decisions to be made; although patients want information about treatment, they typically believe that decision making is the physician's task; physicians do not understand the rationale for the patient's role in decisions; and the medical decision-making process often involves so many people that the patient does not know who is responsible.

Induction of hypoxia inducible factor 1 by oxygen glucose deprivation is attenuated by hypoxic preconditioning in rat cultured neurons

Hypoxia-inducible factor 1 (HIF-1) is a posttranscriptionally regulated transcription factor, controlling several hypoxia-inducible genes. Here we show a rapid and transient increase of HIF-1 DNA binding activity in a dose dependent manner in primary cortical neurons of rats exposed to oxygen glucose deprivation (OGD) for 30, 60, 90, or 120 min. A reduced induction of binding activity was observed when neurons were preconditioned by a non-lethal OGD interval (60 min) 48 h prior to the 90 min OGD. Thus, hypoxic preconditioning reduces activation of HIF-1 binding activity. The molecular mechanism of HIF-1 activation, its target genes, and its role in tolerance induction and/or ischemia induced damage remain to be elucidated.

Effects of cerebral ischemia in mice lacking DNA methyltransferase 1 in post-mitotic neurons

DNA methylation is important for controlling gene expression and is catalyzed by DNA methyltransferase (Dnmt1) an enzyme abundant in brain. We recently demonstrated that mice expressing reduced levels of Dnmt1 are protected from cerebral ischemia. Here, we used the cre/loxP system to produce conditional mutants that lack Dnmt 1 in postmitotic neurons of the postnatal brain. We demonstrate that animals heterozygous for the conditional allele (Dnmt11lox/+) have significantly smaller infarcts following 1 h middle cerebral artery occlusion/reperfusion compared to their wildtype litters. Surprisingly, mice with a deletion of Dnmt1 in post-mitotic neurons (Dnmt11lox/c) were not protected. In conclusion, we demonstrate that reduced levels of Dnmt1, but not its absence, in post-mitotic neurons protect from ischemic brain injury.

Ethical and legal issues related to the use of computer programs in clinical medicine

As computer programs are used with increasing frequency in the clinical setting, ethicists, lawyers, computer scientists, clinicians, and patients must confront a group of problems: In what situations is it appropriate to use a medical computer program? Who should use these programs and how should they be used? What is the legal status of a computer program that provides medical advice? Can a proper balance be achieved between confidentiality of patient information and shared access to records by health care personnel? How can regulatory agencies, physicians, and patients determine if a program is safe for human use? Will programs be able to communicate with users well enough to prevent clinically harmful misunderstandings? Because few if any definitive answers are yet available, these questions remain the subject of much discussion.

Neurotoxicity mechanisms of thioether ecstasy metabolites

3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy"), is a widely abused, psychoactive recreational drug that is known to induce neurotoxic effects. Human and rat hepatic metabolism of MDMA involves N-demethylation to 3,4-methylenedioxyamphetamine (MDA), which is also a drug of abuse. MDMA and MDA are O-demethylenated to N-methyl-alpha-methyldopamine (N-Me-alpha-MeDA) and alpha-methyldopamine (alpha-MeDA), respectively, which are both catechols that can undergo oxidation to the corresponding ortho-quinones. Ortho-quinones may be conjugated with glutathione (GSH) to form glutathionyl adducts, which can be transported into the brain and metabolized to the correspondent N-acetylcysteine (NAC) adducts. In this study we evaluated the neurotoxicity of nine MDMA metabolites, obtained by synthesis: N-Me-alpha-MeDA, alpha-MeDA and their correspondent GSH and NAC adducts. The studies were conducted in rat cortical neuronal cultures, for a 6 h of exposure period, under normal (36.5 degrees C) and hyperthermic (40 degrees C) conditions. Our findings show that thioether MDMA metabolites are strong neurotoxins, significantly more than their correspondent parent catechols. On the other hand, N-Me-alpha-MeDA and alpha-MeDA are more neurotoxic than MDMA. GSH and NAC conjugates of N-Me-alpha-MeDA and alpha-MeDA induced a concentration dependent delayed neuronal death, accompanied by activation of caspase 3, which occurred earlier in hyperthermic conditions. Furthermore, thioether MDMA metabolites time-dependently increased the production of reactive species, concentration-dependently depleted intracellular GSH and increased protein bound quinones. Finally, thioether MDMA metabolites induced neuronal death and oxidative stress was prevented by NAC, an antioxidant and GSH precursor. This study provides new insights into the neurotoxicity mechanisms of thioether MDMA metabolites and highlights their importance in "ecstasy" neurotoxicity.

Predicting post-stroke pneumonia: the PANTHERIS score

OBJECTIVES

Stroke-associated pneumonia (SAP) is a common complication with a known negative impact on neurological outcome. We developed a score to identify patients at highest risk of SAP in order to promote prophylactic measures.

MATERIALS AND METHODS

We conducted a cohort study on a neurological intensive care unit in patients suffering from acute ischemic MCA infarction. Association of predefined demographics, comorbidities, and clinical characteristics with SAP was investigated using logistic regression analysis.

RESULTS

Between 2003 and 2010, a total of 335 patients were included in this analysis. Frequency of SAP was 31.3%. A 12-point scoring system was developed based on the following factors: Glasgow Coma Scale (GCS) [GCS < 9 = 5, GCS 9-12 = 2, GCS > 12 = 0], age [<60 = 0, 60-80 = 1, >80 = 2], increase in systolic arterial blood pressure >200 mmHg within the first 24 h after admission [no = 0, yes = 2], and white blood cell count >11.000/μl [no = 0, yes = 3]. The score revealed excellent discrimination (AUC = 0.85) and calibration (Nagelkerke's R² = 0.46) properties. Predictive properties were reproduced in an internal validation group.

CONCLUSIONS

The PANTHERIS score is a simple scoring system for the prediction of SAP based on easy-to-assess parameters. By identifying patients at high risk, it may guide intense monitoring or prophylactic measures. This score needs to be validated within external datasets.

Ecstasy-induced cell death in cortical neuronal cultures is serotonin 2A-receptor-dependent and potentiated under hyperthermia

Studies on 3,4-methylenedioxymethamphetamine ("ecstasy")-induced neurotoxicity mainly focus on damage of serotonergic terminals. Less attention has been given to neuronal cell death produced by 3,4-methylenedioxymethamphetamine and other amphetamines in areas including the cortex, striatum and thalamus. In the present study we investigated 3,4-methylenedioxymethamphetamine-induced neurotoxicity in neuronal serum free cultures from rat cortex. Since 3,4-methylenedioxymethamphetamine intake induces hyperthermia in both animals and humans, the experiments were performed under normal (36.5 degrees C) and hyperthermic conditions (40 degrees C). Our findings showed a dose-, time- and temperature-dependent apoptotic cell death induced by 3,4-methylenedioxymethamphetamine in cortical neurons. 3,4-Methylenedioxymethamphetamine-induced damage was potentiated under hyperthermia. The neurotoxicity was reduced by the serotonin 2A-receptor antagonists, ketanserin and (2R,4R)-5-[2-[2-[2-(3-methoxyphenyl)ethyl]phenoxy]ethyl]-1-methyl-3-pyrrolidinol hydrochloride, in both normothermic and hyperthermic conditions. (+/-)-2,5-Dimethoxy-4-iodoamphetamine hydrochloride, a model agonist for the serotonin 2A-receptor, also induced a dose- and time-dependent apoptotic cell death. Again, protection was provided by ketanserin and (2R,4R)-5-[2-[2-[2-(3-methoxyphenyl)ethyl]phenoxy]ethyl]-1-methyl-3-pyrrolidinol hydrochloride against (+/-)-2,5-dimethoxy-4-iodoamphetamine hydrochloride-induced neurotoxicity, thereby indicating that the 3,4-methylenedioxymethamphetamine stimulation of the serotonin 2A-receptor leads to neurotoxicity. This study provides for the first time evidence that direct 3,4-methylenedioxymethamphetamine serotonin 2A-receptor stimulation leads to neuronal cortical death. alpha-Phenyl-N-tert-butyl nitrone a free radical scavenger and the nitric oxide synthase inhibitor Nomega-nitro-L-arginine as well as the NMDA-receptor antagonist MK-801 provided protection under normothermia and hyperthermia, thereby suggesting the participation of free radicals in 3,4-methylenedioxymethamphetamine-induced cell death. Since 3,4-methylenedioxymethamphetamine serotonin 2A-receptor agonistic properties lead to neuronal death, clinically available atypical antipsychotic drugs with serotonin 2A-antagonistic properties could be a valuable therapeutic tool against 3,4-methylenedioxymethamphetamine-induced neurodegeneration.

A fluorescence based non-radioactive electrophoretic mobility shift assay

Electrophoretic mobility shift assay (EMSA) or gel shift assay is one of the most powerful methods for studying protein-DNA interactions. Typically, 32P-labeled DNA probes containing the sequence bound by the protein of interest are used in EMSA (rEMSA). Although rEMSA is sensitive and practicable, it relies on the handling of hazardous radioisotopes, and does not easily allow quantification. We developed a non-radioactive procedure using fluorescence (Cyano dye Cy5) labeled oligodeoxynucleotide duplexes as specific probes (fEMSA) and an automatic DNA sequencer for analysis. Testing different DNA-binding proteins (restriction endonuclease EcoRII, transcription factor NFkappaB and it's subunit p50) the results in fEMSA and rEMSA are similar in regard to quality, reproducibility, and sensitivity. fEMSA allows a semiquantitative screening of large amounts of samples for specific DNA binding activities and is, therefore, a high throughput technology for semiquantitative analysis of DNA-protein interaction.

Cooperative binding properties of restriction endonuclease EcoRII with DNA recognition sites

EcoRII is a member of the expanding group of type IIe restriction endonucleases that share the distinguishing feature of requiring cooperativity between two recognition sites in their substrate DNA. To determine the stoichiometry of the active DNA-enzyme complex and the mode of cooperative interaction, we have investigated the dependence of EcoRII cleavage on the concentration of EcoRII dimers. Maximal restriction was observed at dimer/site ratios of 0.25 and 0. 5. The molecular weight of the DNA-enzyme complex eluted from a gel filtration column also corresponds to a dimeric enzyme structure bound to two substrate sites. We conclude that one EcoRII dimer is sufficient to interact cooperatively with two DNA recognition sites. A Lac repressor "barrier" bound between two normally reactive EcoRII sites did not inhibit restriction endonuclease activity, indicating that cooperativity between EcoRII sites is achieved by bending or looping of the intervening DNA stretch. Comparative cleavage of linear substrates with differently spaced interacting sites revealed an inverse correlation between cleavage rate and site distance. At the optimal distance of one helical turn, EcoRII cleavage is independent of the orientation of the recognition sequence in the DNA double strand.

Severe neutropenia during cabazitaxel treatment is associated with survival benefit in men with metastatic castration-resistant prostate cancer (mCRPC): A post-hoc analysis of the TROPIC phase III trial

BACKGROUND

Cabazitaxel significantly improves overall survival (OS) in men with metastatic castration-resistant prostate cancer (mCRPC) progressing during or after docetaxel, but is associated with a higher rate of grade ≥3 neutropenia compared with docetaxel. We thus examined the relationship between cabazitaxel-induced grade ≥3 neutropenia, baseline neutrophil-lymphocyte ratio (NLR) and treatment outcomes.

METHODS

Data from the experimental arm of the TROPIC phase 3 trial which randomly assigned men with mCRPC to cabazitaxel or mitoxantrone every 3 weeks, both combined with daily prednisone, were analysed. The influence on OS (primary end-point) and progression-free survival (PFS) of at least one episode of grade ≥3 neutropenia during cabazitaxel therapy was investigated using Cox regression models, adjusted for pain at baseline. The relationships with prostate-specific antigen (PSA) responses during cabazitaxel therapy and baseline NLR were also analysed.

FINDINGS

The occurrence of grade ≥3 neutropenia during cabazitaxel therapy was associated with a prolonged OS (median 16.3 versus 14.0 months, hazard ratio (HR) [95% confidence interval] = 0.65 [0.43-0.97], p = 0.035), a twice longer PFS (median 5.3 versus 2.6 months, HR = 0.56 [0.40-0.79], p = 0.001) and a higher confirmed PSA response ≥50% (49.8% versus 24.4%, p = 0.005), as compared with patients who did not develop grade ≥3 neutropenia. Grade ≥3 neutropenia was more common in case of NLR <3 as compared with NLR ≥3 at baseline (88.8% versus 75.3%, p = 0.002). Combining low NLR at baseline and grade ≥3 neutropenia during therapy was associated with the longest OS (median 19.2 months) while high NLR at baseline and no grade ≥3 neutropenia was associated with a poor OS (median 12.9 months, HR 0.46 [0.28-0.76], p = 0.002). In the subgroup of neutropenic patients the median OS was 19.7 months in those treated with granulocyte colony-stimulating factor (G-CSF) and 16 months on those without G-CSF support.

INTERPRETATION

This post-hoc analysis of TROPIC suggests that the occurrence of grade ≥3 neutropenia with cabazitaxel is associated with improved OS and PFS. Patients with a low NLR at baseline were more likely to develop grade ≥3 neutropenia during cabazitaxel therapy and showed the longest OS. High NLR at baseline and no grade ≥3 neutropenia during therapy was associated with poor outcomes which may suggest insufficient drug exposure or a limited impact on the tumour-associated immune response. Primary or secondary prophylactic use of G-CSF had no adverse impact for outcome. If prospectively confirmed, these results would justify maintaining the intended cabazitaxel dose of 25 mg/m(2) whenever possible.

Regions of endonuclease EcoRII involved in DNA target recognition identified by membrane-bound peptide repertoires

Target sequence-specific DNA binding regions of the restriction endonuclease EcoRII were identified by screening a membrane-bound EcoRII-derived peptide scan with an EcoRII recognition site (CCWGG) oligonucleotide duplex. Dodecapeptides overlapping by nine amino acids and representing the complete protein were prepared by spot synthesis. Two separate DNA binding regions, amino acids 88-102 and amino acids 256-273, which share the consensus motif KXRXXK, emerged. Screening 570 single substitution analogues obtained by exchanging every residue of both binding sites for all other amino acids demonstrated that replacing basic residues in the consensus motifs significantly reduced DNA binding. EcoRII mutant enzymes generated by substituting alanine or glutamic acid for the consensus lysine residues in DNA binding site I expressed attenuated DNA binding, whereas corresponding substitutions in DNA binding site II caused impaired cleavage, but enzyme secondary structure was unaffected. Furthermore, Glu96, which is part of a potential catalytic motif and also locates to DNA binding site I, was demonstrated to be critical for DNA cleavage and binding. Homology studies of DNA binding site II revealed strong local homology to SsoII (recognition sequence, CCNGG) and patterns of sequence conservation, suggesting the existence of functionally related DNA binding sites in diverse restriction endonucleases with recognition sequences containing terminal C:G or G:C pairs.

The G protein-coupled estrogen receptor (GPER) is expressed in two different subcellular localizations reflecting distinct tumor properties in breast cancer

INTRODUCTION

The G protein-coupled estrogen receptor (GPER) is a novel estrogen receptor that mediates proliferative effects induced by estrogen but also by tamoxifen. The aim of our study was to analyze the frequency of GPER in a large collective of primary invasive breast carcinomas, with special emphasis on the subcellular expression and to evaluate the association with clinicopathological parameters and patient overall survival.

METHODS

The tissue microarrays from formalin-fixed, paraffin embedded samples of primary invasive breast carcinomas (n = 981) were analyzed for GPER expression using immunohistochemistry. Expression data were compared to the clinicopathological parameters and overall survival. GPER localization was also analyzed in two immortalized breast cancer cell lines T47D and MCF7 by confocal immunofluorescence microscopy.

RESULTS

A predominantly cytoplasmic GPER expression was found in 189 carcinomas (19.3%), whereas a predominantly nuclear expression was observed in 529 cases (53.9%). A simultaneous comparable positive expression of both patterns was found in 32 of 981 cases (3.2%), and negative staining was detected in 295 cases (30%). Confocal microscopy confirmed the occurrence of cytoplasmic and nuclear GPER expression in T47D and MCF7. Cytoplasmic GPER expression was significantly associated with non-ductal histologic subtypes, low tumor stage, better histologic differentiation, as well as Luminal A and B subtypes. In contrast, nuclear GPER expression was significantly associated with poorly differentiated carcinomas and the triple-negative subtype. In univariate analysis, cytoplasmic GPER expression was associated with better overall survival (p = 0.012).

CONCLUSION

Our data suggest that predominantly cytoplasmic and/or nuclear GPER expression are two distinct immunohistochemical patterns in breast carcinomas and may reflect different biological features, reason why these patterns should be clearly distinguished in histological evaluations. Prospective studies will be needed to assess whether the expression status of GPER in breast carcinomas should be routinely observed by clinicians, for instance, before implementing endocrine breast cancer treatment.

Dangerousness, confidentiality, and the duty to warn

The Tarasoff decision, by imposing on psychiatrists an obligation to warn the intended victim of threats made by a patient, but only under certain vaguely specified circumstances, may stampede psychiatrists into issuing such warnings to avoid possible legal liability no matter how remote the risk of harm may actually be. The authors suggest that the ill effects of such a reaction by psychiatrists--breach of confidentiality and the attendant erosion of trust and harm to the therapeutic alliance--can often be easily avoided by taking less drastic steps, some of which are illustrated by case presentations.

Downregulation of c-Jun expression and cell cycle regulatory molecules in acute myeloid leukemia cells upon CD44 ligation

In the present study, we investigated the mechanism of CD44 ligation with the anti-CD44 monoclonal antibody A3D8 to inhibit the proliferation of human acute myeloid leukemia (AML) cells. The effects of A3D8 on myeloid cells were associated with specific disruption of cell cycle events and induction of G0/G1 arrest. Induction of G0/G1 arrest was accompanied by an increase in the expression of p21, attenuation of pRb phosphorylation and associated with decreased Cdk2 and Cdk4 kinase activities. Since c-Jun is an important regulator of proliferation and cell cycle progression, we analysed its role in A3D8-mediated growth arrest. We observed that A3D8 treatment of AML patient blasts and HL60/U937 cells led to the downregulation of c-Jun expression at mRNA and protein level. Transient transfection studies showed the inhibition of c-jun promoter activity by A3D8, involving both AP-1 sites. Furthermore, A3D8 treatment caused a decrease in JNK protein expression and a decrease in the level of phosphorylated c-Jun. Ectopic overexpression of c-Jun in HL60 cells was able to induce proliferation and prevent the antiproliferative effects of A3D8. In summary, these data identify an important functional role of c-Jun in the induction of cell cycle arrest and proliferation arrest of myeloid leukemia cells because of the ligation of the cell surface adhesion receptor CD44 by anti-CD44 antibody. Moreover, targeting of G1 regulatory proteins and the resulting induction of G1 arrest by A3D8 may provide new insights into antiproliferative and differentiation therapy of AML.