Mitochondrial-derived vesicles compensate for loss of LC3-mediated mitophagy

Mitochondria are critical metabolic and signaling hubs, and dysregulated mitochondrial homeostasis is implicated in many diseases. Degradation of damaged mitochondria by selective GABARAP/LC3-dependent macro-autophagy (mitophagy) is critical for maintaining mitochondrial homeostasis. To identify alternate forms of mitochondrial quality control that functionally compensate if mitophagy is inactive, we selected for autophagy-dependent cancer cells that survived loss of LC3-dependent autophagosome formation caused by inactivation of ATG7 or RB1CC1/FIP200. We discovered rare surviving autophagy-deficient clones that adapted to maintain mitochondrial homeostasis after gene inactivation and identified two enhanced mechanisms affecting mitochondria including mitochondrial dynamics and mitochondrial-derived vesicles (MDVs). To further understand these mechanisms, we quantified MDVs via flow cytometry and confirmed an SNX9-mediated mechanism necessary for flux of MDVs to lysosomes. We show that the autophagy-dependent cells acquire unique dependencies on these processes, indicating that these alternate forms of mitochondrial homeostasis compensate for loss of autophagy to maintain mitochondrial health.

Including a Student with Multiple Disabilities and Visual Impairment in Her Neighborhood School

This article begins with a literature review of main-streaming students with multiple disabilities and visual impairment in general schools, stressing the importance of opportunities for peer interaction that are prevalent in regular settings. It then describes a program carried out with a 5-year-old student attending her neighborhood school in Auckland, New Zealand. Comments of the people involved in the program, including the principal, the teachers, the teacher's aide, family members, and fellow pupils, are reported, and the success of the program is discussed.

Autophagy inhibition overcomes multiple mechanisms of resistance to BRAF inhibition in brain tumors

Kinase inhibitors are effective cancer therapies, but tumors frequently develop resistance. Current strategies to circumvent resistance target the same or parallel pathways. We report here that targeting a completely different process, autophagy, can overcome multiple BRAF inhibitor resistance mechanisms in brain tumors. BRAF^V600Emutations occur in many pediatric brain tumors. We previously reported that these tumors are autophagy-dependent and a patient was successfully treated with the autophagy inhibitor chloroquine after failure of the BRAF^V600E inhibitor vemurafenib, suggesting autophagy inhibition overcame the kinase inhibitor resistance. We tested this hypothesis in vemurafenib-resistant brain tumors. Genetic and pharmacological autophagy inhibition overcame molecularly distinct resistance mechanisms, inhibited tumor cell growth, and increased cell death. Patients with resistance had favorable clinical responses when chloroquine was added to vemurafenib. This provides a fundamentally different strategy to circumvent multiple mechanisms of kinase inhibitor resistance that could be rapidly tested in clinical trials in patients with BRAF^V600E brain tumors.

DOI:http://dx.doi.org/10.7554/eLife.19671.001

Cancers of the brain and spine are the second most common kind of tumor in children, after cancers of the blood and bone marrow. Yet brain and spine tumors kill more children than any other cancer, in part because many become resistant to treatment.

Like in other cancers, cells in brain and spine tumors often use a process called autophagy to survive the treatments that are used to try and kill them. This process allows cells to recycle proteins and other things inside the cell and use them for energy when the cell is under stress. In 2014, researchers reported that brain tumors carrying a mutation called BRAF^V600E rely on autophagy to survive treatment with medications that target this mutation. These findings suggested that blocking autophagy might make the medications more effective against BRAF^V600Emutant tumors and overcome the resistance.

Now, Mulcahy Levy et al. – who include most of the researchers involved in the 2014 study – report that blocking autophagy does indeed overcome this kind of resistance in multiple types of tumor. The experiments made use of human brain tumor cells that can be grown in the laboratory and have been widely studied, as well as samples collected from patients.

Mulcahy Levy et al. were able to block autophagy in the tumor cells by using genetic methods and, importantly, by using an approved and inexpensive drug that could be rapidly translated into clinical trials. Together these findings suggest that blocking autophagy in patients might be a safe and effective strategy to improve their response to existing therapies that target the BRAF^V600E mutation. Future clinical trials are now needed to test more patients and verify if this treatment plan can be broadly effective in patients with these types of brain cancers.

DOI:http://dx.doi.org/10.7554/eLife.19671.002

Non-cell-autonomous Effects of Autophagy Inhibition in Tumor Cells Promote Growth of Drug-resistant Cells

Autophagy, the mechanism by which cells deliver material to the lysosome, has been associated with resistance to anticancer drugs, leading autophagy inhibition to be widely studied as a potential chemosensitization strategy for cancer cells. This strategy is based on the idea that inhibition of autophagy will increase drug sensitivity and kill more cancer cells. Here we report an unintended negative effect of this strategy. When modeling the effect of drug resistance in a heterogeneous cancer cell population, we found that autophagy inhibition in drug-sensitive tumor cells causes increased growth of drug-resistant cells in the population through a mechanism involving caspase activation and prostaglandin E₂ signaling. These results emphasize the importance of understanding how autophagy manipulation in a tumor cell can have both cell-autonomous and nonautonomous effects and suggest that attempts to chemosensitize by inhibiting autophagy could be enhanced by adopting methods aimed at reducing tumor repopulation.

Autophagy Supports Breast Cancer Stem Cell Maintenance by Regulating IL6 Secretion

Autophagy is a mechanism by which cells degrade cellular material to provide nutrients and energy for survival during stress. The autophagy is thought to be a critical process for cancer stem cell (CSC) or tumor-initiating cell maintenance but the mechanisms by which autophagy supports survival of CSCs remain poorly understood. In this study, inhibition of autophagy by knockdown of ATG7 or BECN1 modified the CD44(+)/CD24(low/-) population in breast cancer cells by regulating CD24 and IL6 secretion. In a breast cancer cell line that is independent of autophagy for survival, autophagy inhibition increased IL6 secretion to the media. On the other hand, in an autophagy-dependent cell line, autophagy inhibition decreased IL6 secretion, cell survival, and mammosphere formation. In these cells, IL6 treatment or conditioned media from autophagy-competent cells rescued the deficiency in mammosphere formation induced by autophagy inhibition. These results reveal that autophagy regulates breast CSC maintenance in autophagy-dependent breast cancer cells by modulating IL6 secretion implicating autophagy as a potential therapeutic target in breast cancer.

IMPLICATIONS

Modulation of autophagy in breast cancer has different and even opposite effects, indicating the need for a selection strategy when trying to manipulate autophagy in the context of cancer therapy.

Regulation of autophagy and chloroquine sensitivity by oncogenic RAS in vitro is context-dependent

Chloroquine (CQ) is an antimalarial drug and late-stage inhibitor of autophagy currently FDA-approved for use in the treatment of rheumatoid arthritis and other autoimmune diseases. Based primarily on its ability to inhibit autophagy, CQ and its derivative, hydroxychloroquine, are currently being investigated as primary or adjuvant therapy in multiple clinical trials for cancer treatment. Oncogenic RAS has previously been shown to regulate autophagic flux, and cancers with high incidence of RAS mutations, such as pancreatic cancer, have been described in the literature as being particularly susceptible to CQ treatment, leading to the hypothesis that oncogenic RAS makes cancer cells dependent on autophagy. This autophagy "addiction" suggests that the mutation status of RAS in tumors could identify patients who would be more likely to benefit from CQ therapy. Here we show that RAS mutation status itself is unlikely to be beneficial in such a patient selection because oncogenic RAS does not always promote autophagy addiction. Moreover, oncogenic RAS can have opposite effects on both autophagic flux and CQ sensitivity in different cells. Finally, for any given cell type, the positive or negative effect of oncogenic RAS on autophagy does not necessarily predict whether RAS will promote or inhibit CQ-mediated toxicity. Thus, although our results confirm that different tumor cell lines display marked differences in how they respond to autophagy inhibition, these differences can occur irrespective of RAS mutation status and, in different contexts, can either promote or reduce chloroquine sensitivity of tumor cells.

Autophagy controls the kinetics and extent of mitochondrial apoptosis by regulating PUMA levels

Macroautophagy is thought to protect against apoptosis; however, underlying mechanisms are poorly understood. We examined how autophagy affects canonical death receptor-induced mitochondrial outer membrane permeabilization (MOMP) and apoptosis. MOMP occurs at variable times in a population of cells, and this is delayed by autophagy. Additionally, autophagy leads to inefficient MOMP, after which some cells die through a slower process than typical apoptosis and, surprisingly, can recover and divide afterward. These effects are associated with p62/SQSTM1-dependent selective autophagy causing PUMA levels to be kept low through an indirect mechanism whereby autophagy affects constitutive levels of PUMA mRNA. PUMA depletion is sufficient to prevent the sensitization to apoptosis that occurs when autophagy is blocked. Autophagy can therefore control apoptosis via a key regulator that makes MOMP faster and more efficient, thus ensuring rapid completion of apoptosis. This identifies a molecular mechanism whereby cell-fate decisions can be determined by autophagy.

Inhibiting autophagy by shRNA knockdown: cautions and recommendations

A glance through Autophagy or any other journal in this field shows that it is very common to block autophagy by RNA interference-based knockdown of ATG mRNAs in mammalian cell lines. Our lab's experience is that this approach can easily make for failed experiments because good knockdown of even essential autophagy regulators does not necessarily mean you will get good inhibition of autophagy, and, over time, cells can find ways to circumvent the inhibitory effects of the knockdown.

The vitamin E analogue α-TEA stimulates tumor autophagy and enhances antigen cross-presentation

The semisynthetic vitamin E derivative alpha-tocopheryloxyacetic acid (α-TEA) induces tumor cell apoptosis and may offer a simple adjuvant supplement for cancer therapy if its mechanisms can be better understood. Here we report that α-TEA also triggers tumor cell autophagy and that it improves cross-presentation of tumor antigens to the immune system. α-TEA stimulated both apoptosis and autophagy in murine mammary and lung cancer cells and inhibition of caspase-dependent apoptosis enhanced α-TEA-induced autophagy. Cell exposure to α-TEA generated double-membrane-bound vesicles indicative of autophagosomes, which efficiently cross-primed antigen-specific CD8(+) T cells. Notably, vaccination with dendritic cells pulsed with α-TEA-generated autophagosomes reduced lung metastases and increased the survival of tumor-bearing mice. Taken together, our findings suggest that both autophagy and apoptosis signaling programs are activated during α-TEA-induced tumor cell killing. We suggest that the ability of α-TEA to stimulate autophagy and enhance cross-priming of CD8(+) T cells might be exploited as an adjuvant strategy to improve stimulation of antitumor immune responses.

Inhibition of autophagy impairs tumor cell invasion in an organotypic model

Autophagy is a membrane-trafficking process that delivers cytoplasmic constituents to lysosomes for degradation. It contributes to energy and organelle homeostasis and the preservation of proteome and genome integrity. Although a role in cancer is unquestionable, there are conflicting reports that autophagy can be both oncogenic and tumor suppressive, perhaps indicating that autophagy has different roles at different stages of tumor development. In this report, we address the role of autophagy in a critical stage of cancer progression-tumor cell invasion. Using a glioma cell line containing an inducible shRNA that targets the essential autophagy gene Atg12, we show that autophagy inhibition does not affect cell viability, proliferation or migration but significantly reduces cellular invasion in a 3D organotypic model. These data indicate that autophagy may play a critical role in the benign to malignant transition that is also central to the initiation of metastasis.

Chloroquine sensitizes breast cancer cells to chemotherapy independent of autophagy

Chloroquine (CQ) is a 4-aminoquinoline drug used for the treatment of diverse diseases. It inhibits lysosomal acidification and therefore prevents autophagy by blocking autophagosome fusion and degradation. In cancer treatment, CQ is often used in combination with chemotherapeutic drugs and radiation because it has been shown to enhance the efficacy of tumor cell killing. Since CQ and its derivatives are the only inhibitors of autophagy that are available for use in the clinic, multiple ongoing clinical trials are currently using CQ or hydroxychloroquine (HCQ) for this purpose, either alone, or in combination with other anticancer drugs. Here we show that in the mouse breast cancer cell lines, 67NR and 4T1, autophagy is induced by the DNA damaging agent cisplatin or by drugs that selectively target autophagy regulation, the PtdIns3K inhibitor LY294002, and the mTOR inhibitor rapamycin. In combination with these drugs, CQ sensitized to these treatments, though this effect was more evident with LY294002 and rapamycin treatment. Surprisingly, however, in these experiments CQ sensitization occurred independent of autophagy inhibition, since sensitization was not mimicked by Atg12, Beclin 1 knockdown or bafilomycin treatment, and occurred even in the absence of Atg12. We therefore propose that although CQ might be helpful in combination with cancer therapeutic drugs, its sensitizing effects can occur independently of autophagy inhibition. Consequently, this possibility should be considered in the ongoing clinical trials where CQ or HCQ are used in the treatment of cancer, and caution is warranted when CQ treatment is used in cytotoxic assays in autophagy research.

Distinct TRAIL resistance mechanisms can be overcome by proteasome inhibition but not generally by synergizing agents

One impediment to the use of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor-targeted agents as antitumor drugs is the evolution of resistance, a common problem in cancer. On the contrary, many different kinds of drugs synergize with TRAIL in TRAIL-sensitive tumor cells, raising the question whether one can overcome resistance with the same drugs producing synergy. This is an important question, because recent clinical trials suggest that combination treatments with cytotoxic drugs and TRAIL receptor-targeted agents do not provide additional benefit compared with cytotoxic agents on their own. Such results might be expected if drug combinations that synergize in sensitive tumor cells but cannot overcome TRAIL resistance are used in patients whose tumors were not selected for retention of TRAIL sensitivity. We tested this idea by creating isogenic tumor cells with acquired TRAIL resistance or defined mechanisms of resistance that occur in human tumors and then comparing them to the TRAIL-sensitive parental cell line. Although diverse classes of anticancer drugs were all able to synergize with TRAIL in sensitive cells, most agents were unable to overcome resistance and there was no relationship between the amount of synergy seen with a particular agent and its ability to overcome acquired resistance. An important exception was proteasome inhibitors, which were, however, able to overcome diverse resistance mechanisms. Our findings suggest that one should select drugs for TRAIL receptor agonist combination therapy based not just on their ability to synergize, but rather on their ability to overcome resistance as well as synergize.

EGFR-targeted diphtheria toxin stimulates TRAIL killing of glioblastoma cells by depleting anti-apoptotic proteins

Current treatments for Glioblastoma multiforme (GBM) involve surgery, radiotherapy, and cytotoxic chemotherapy; however, these treatments are not effective and there is an urgent need for better treatments. We investigated GBM cell killing by a novel drug combination involving DT-EGF, an Epidermal Growth Factor Receptor-targeted bacterial toxin, and Tumor Necrosis Factor-Related Apoptosis Inducing Ligand (TRAIL) or antibodies that activate the TRAIL receptors DR4 and DR5. DT-EGF kills GBM cells by a non apoptotic mechanism whereas TRAIL kills by inducing apoptosis. GBM cells treated with DT-EGF and TRAIL were killed in a synergistic fashion in vitro and the combination was more effective than either treatment alone in vivo. Tumor cell death with the combination occurred by caspase activation and apoptosis due to DT-EGF positively regulating TRAIL killing by depleting FLIP, a selective inhibitor of TRAIL receptor-induced apoptosis. These data provide a mechanism-based rationale for combining targeted toxins and TRAIL receptor agonists to treat GBM.

Regulation of HMGB1 release by autophagy

The characteristics of tumor cell killing by an anticancer agent can determine the long-term effectiveness of the treatment. For example, if dying tumor cells release the immune modulator HMGB1 after treatment with anticancer drugs, they can activate a tumor-specific immune response that boosts the effectiveness of the initial treatment. Recent work from our group examined the mechanism of action of a targeted toxin called DT-EGF that selectively kills Epidermal Growth Factor Receptor-expressing tumor cells. We found that DT-EGF kills glioblastoma cells by a caspase-independent mechanism that involves high levels of autophagy, which inhibits cell death by blocking apoptosis. In contrast, DT-EGF kills epithelial tumor cells by caspase-dependent apoptosis and in these cells autophagy is not induced. These differences allowed us to discover that the different death mechanisms were associated with differences in the release of HMGB1 and that autophagy induction is required and sufficient to cause release of HMGB1 from the dying cells. These data identify a new function for autophagy during cell death and open up the possibility of manipulating autophagy during cancer treatment as a way to influence the immunogenicity of dying tumor cells.

Autophagy regulates selective HMGB1 release in tumor cells that are destined to die

Macroautophagy (hereafter referred to as autophagy) can increase or decrease the amount of cell death in response to various stimuli. To test if autophagy also controls the characteristics associated with dying cells, we studied tumor cell killing by Epidermal Growth Factor Receptor (EGFR)-targeted diphtheria toxin (DT-EGF). DT-EGF kills epithelial and glioblastoma tumor cells with similar efficiency but by different mechanisms that depend on whether the cells activate autophagy when treated with the drug. Dying cells in which autophagy is induced selectively release the immune modulator HMGB1 without causing lysis of the cell membrane and classical necrosis. Conversely, cells that are killed by DT-EGF where autophagy is blocked, activate caspases but retain HMGB1. These data suggest that it may be feasible to manipulate the immunogenicity of dying cells by increasing or decreasing autophagy.

Tumor-derived Mutations in the TRAIL Receptor DR5 Inhibit TRAIL Signaling through the DR4 Receptor by Competing for Ligand Binding

TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) is a cytokine that preferentially induces apoptosis in tumor cells compared with normal cells through two receptors (DR4 and DR5). Somatic mutations in these receptors have been found in different kinds of cancer; however, it is poorly understood how the mutations affect signaling. We found that point mutations (L334F, E326K, E338K, and K386N) that were identified in human tumors result in the DR5 receptor losing its ability to form a functional death-inducing signaling complex and induce apoptosis. The mutant receptors also have a "dominant negative" effect whereby they inhibit the ability of TRAIL to induce apoptosis through functional DR4 receptors. This dominant negative mechanism is achieved through competition for TRAIL binding as shown by experiments where the ability of the mutant DR5 receptor to bind with the ligand was abolished, thus restoring TRAIL signaling through DR4. The inhibitory effect on signaling through the wild-type DR4 protein can be overcome if the inhibitory mechanism is bypassed by using a DR4-agonistic antibody that is not subject to this competition. This study provides a molecular basis for the use of specific therapeutic agonists of TRAIL receptors in people whose tumors harbor somatic DR5 mutations.

Acute pharyngolaryngeal oedema in a pre-eclamptic parturient with systemic lupus erythematosus and a recent renal transplant

The case of a 30-year-old parous patient with multi-organ involvement due to systemic lupus erythematosus and severe hypertension at 33 weeks gestation is described. Despite uneventful general anaesthesia for a classical caesarean section she developed acute airway obstruction postoperatively which was attributed to pre-eclampsia induced laryngeal oedema.

Selective inactivation of a Fas-associated death domain protein (FADD)-dependent apoptosis and autophagy pathway in immortal epithelial cells

Although evasion of apoptosis is thought to be required for the development of cancer, it is unclear which cell death pathways are evaded. We previously identified a novel epithelial cell death pathway that works in normal cells but is inactivated in tumor cells, implying that it may be targeted during tumor development. The pathway can be activated by the Fas-associated death domain (FADD) of the adaptor protein but is distinct from the known mechanism of FADD-induced apoptosis through caspase-8. Here, we show that a physiological signal (tumor necrosis factor-related apoptosis-inducing ligand) can kill normal epithelial cells through the endogenous FADD protein by using the novel FADD death domain pathway, which activates both apoptosis and autophagy. We also show that selective resistance to this pathway occurs when primary epithelial cells are immortalized and that this occurs through a mechanism that is independent of known events (telomerase activity, and loss of function of p53, Rb, INK4a, and ARF) that are associated with immortalization. These data identify a novel cell death pathway that combines apoptosis and autophagy and that is selectively inactivated at the earliest stages of epithelial cancer development.

Induction of apoptosis by tumor cell-targeted toxins

Targeted toxins are fusion proteins that combine a targeting molecule that selectively binds to and enters tumor cells with a protein toxin that kills the target cells. These molecules represent an exciting approach to develop effective cancer-specific therapeutics that have few side effects on normal tissues and numerous such toxins are in various stages of pre-clinical and clinical development to treat a wide variety of tumors. In this review, we discuss this strategy, describe ways that the toxins activate the apoptosis machinery and discuss future developments in this field.

Economic evaluation of infertility treatment for tubal disease

PURPOSE

The number of published studies comparing cost-effectiveness of tubal surgery and IVF treatment is limited, in part because of the difficulties of conducting randomized trials, given that IVF is now a clinically accepted treatment and the decision to offer surgery or IVF is often dictated by the severity of the tubal disease and by the availability of the methods. The aim of this study was to compare the costs of our policy of offering tubal surgery to patients with mild or moderate tubal disease with the cost of offering IVF to these and severe tubal disease.

METHODS

In this retrospective cohort study patients with tubal pathology as the sole reason for their infertility were included: 61 patients in the tubal surgery group and 464 patients in the IVF group. The delivery rates and costs per delivery were compared.

RESULTS

Delivery rates were 28% in the tubal surgery group within 2 years of follow-up and 52% in the IVF group that involved up to three cycles of treatment. This economic evaluation demonstrated only small differences in the average cost when considering the cost per delivery.

CONCLUSIONS

With a policy involving strict selection of patients, tubal surgery will continue to have a role in the treatment of infertility.

Apoptosis by leukemia cell-targeted diphtheria toxin occurs via receptor-independent activation of Fas-associated death domain protein

PURPOSE

We examined the mechanism of action of a targeted fusion toxin consisting of diphtheria toxin fused to granulocyte macrophage colony stimulating factor (GMCSF) (DT(388)-GMCSF), which was designed to selectively kill acute myeloid leukemia cells.

EXPERIMENTAL DESIGN AND RESULTS

U937 cells treated with DT(388)-GMCSF underwent apoptosis as shown by chromatin degradation and cellular and nuclear fragmentation. This apoptosis was prevented by a general caspase inhibitor. DT(388)-GMCSF treatment resulted in activation of the initiator caspases 8 and 9 and effector caspases. A selective caspase 8 inhibitor prevented activation of caspase 9, whereas a selective caspase 9 inhibitor did not prevent activation of caspase 8, indicating that caspase 8 activation is the proximal event in DT(388)-GMCSF-induced apoptosis. Caspase 8 was activated through a Fas-associated death domain protein (FADD)-dependent mechanism as demonstrated by inhibition of DT(388)-GMCSF-induced apoptosis on expression of a dominant negative FADD molecule. However, unlike most FADD-dependent apoptosis, this pathway may not involve death receptors, including Fas, tumor necrosis factor receptor 1, or tumor necrosis factor-related apoptosis-inducing ligand receptors, because inhibitors of the receptors did not prevent DT(388)-GMCSF-induced apoptosis.

CONCLUSIONS

These data indicate that targeted toxins induce apoptosis by activating components of the death receptor pathway in a receptor-independent manner.

Caspase- and serine protease-dependent apoptosis by the death domain of FADD in normal epithelial cells

The adapter protein FADD consists of two protein interaction domains: a death domain and a death effector domain. The death domain binds to activated death receptors such as Fas, whereas the death effector domain binds to procaspase 8. An FADD mutant, which consists of only the death domain (FADD-DD), inhibits death receptor-induced apoptosis. FADD-DD can also activate a mechanistically distinct, cell type-specific apoptotic pathway that kills normal but not cancerous prostate epithelial cells. Here, we show that this apoptosis occurs through activation of caspases 9, 3, 6, and 7 and a serine protease. Simultaneous inhibition of caspases and serine proteases prevents FADD-DD-induced death. Inhibition of either pathway alone does not prevent cell death but does affect the morphology of the dying cells. Normal prostate epithelial cells require both the caspase and serine protease inhibitors to efficiently prevent apoptosis in response to TRAIL. In contrast, the serine protease inhibitor does not affect TRAIL-induced death in prostate tumor cells suggesting that the FADD-DD-dependent pathway can be activated by TRAIL. This apoptosis pathway is activated in a cell type-specific manner that is defective in cancer cells, suggesting that this pathway may be targeted during cancer development.

15-Deoxy-delta12,14-prostaglandin J2-induced apoptosis does not require PPARgamma in breast cancer cells

Naturally occurring derivatives of arachidonic acid are potent agonists for the nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPARgamma) and block cancer cell proliferation through the induction of apoptosis. We have previously reported that induction of apoptosis using cyclopentenone prostaglandins of the J series, including 15deoxydelta(12,14)PGJ(2) (15dPGJ(2)), is associated with a high degree of PPAR-response element (PPRE) activity and requires early de novo gene expression in breast cancer cells. In the current study, we used pharmacologic and genetic approaches to test the hypothesis that PPARgamma is required for 15dPGJ(2)-induced apoptosis. The PPARgamma agonists 15dPGJ(2), trogliltazone (TGZ), and GW7845, a synthetic and highly selective tyrosine-based PPARgamma agonist, all increased transcriptional activity of PPARgamma, and expression of CD36, a PPARgamma-dependent gene. Transcriptional activity and CD36 expression was reduced by GW9662, a selective and irreversible PPARgamma antagonist, but GW9662 did not block apoptosis induced by 15dPGJ(2). Moreover, dominant negative expression of PPARgamma blocked PPRE transcriptional activity, but did not block 15dPGJ(2)-induced apoptosis. These studies show that while 15dPGJ(2) activates PPRE-mediated transcription, PPARgamma is not required for 15dPGJ(2)-induced apoptosis in breast cancer cells. Other likely mechanisms through which cyclopentenone prostaglandins induce apoptosis of cancer cells are discussed.

Nuclear and cytoplasmic shuttling of TRADD induces apoptosis via different mechanisms

The adapter protein tumor necrosis factor receptor (TNFR)1-associated death domain (TRADD) plays an essential role in recruiting signaling molecules to the TNFRI receptor complex at the cell membrane. Here we show that TRADD contains a nuclear export and import sequence that allow shuttling between the nucleus and the cytoplasm. In the absence of export, TRADD is found within nuclear structures that are associated with promyelocytic leukemia protein (PML) nuclear bodies. In these structures, the TRADD death domain (TRADD-DD) can activate an apoptosis pathway that is mechanistically distinct from its action at the membrane-bound TNFR1 complex. Apoptosis by nuclear TRADD-DD is promyelocytic leukemia protein dependent, involves p53, and is inhibited by Bcl-xL but not by caspase inhibitors or dominant negative FADD (FADD-DN). Conversely, apoptosis induced by TRADD in the cytoplasm is resistant to Bcl-xL, but sensitive to caspase inhibitors and FADD-DN. These data indicate that nucleocytoplasmic shuttling of TRADD leads to the activation of distinct apoptosis mechanisms that connect the death receptor apparatus to nuclear events.

Hydrosalpinx and IVF outcome: cumulative results after salpingectomy in a randomized controlled trial

BACKGROUND

A randomized controlled trial of salpingectomy prior to IVF in patients with hydrosalpinges has been conducted in Scandinavia. The results from the first transfer cycle have been published and clearly demonstrated an improved pregnancy outcome after salpingectomy had been performed in patients with hydrosalpinges large enough to be visible on ultrasound. The present article is aimed at analysing the effect of salpingectomy on cumulative birth rate, including all individual transfer cycles.

METHODS AND RESULTS

A total of 186 women underwent 452 cycles. Among the 77 women randomized to no surgical intervention, 24 underwent salpingectomy after one or two failed cycles. Cumulative results were analysed by Cox regression, taking into account the number of cycles per patient and the presence of a salpingectomy after a previous transfer. Salpingectomy implied a significant increase in birth rate (hazard ratio 2.1, 95% CI 1.6-3.6, P = 0.014). Within the subgroup of patients with ultrasound-visible hydrosalpinges, the birth rate was even higher (hazard ratio 3.8, 95% CI 1.5-9.2, P = 0.004). Implantation rate was significantly higher in patients who had undergone salpingectomy (27.2% versus 20.2, P = 0.03) and, in the subgroup of patients with ultrasound-visible hydrosalpinges, the difference was even larger (30.3% versus 17.1%, P = 0.003).

CONCLUSIONS

The results of the cumulative cycles strengthen the recommendation for a laparoscopic salpingectomy prior to IVF in patients with ultrasound-visible hydrosalpinges.

An apoptosis signaling pathway induced by the death domain of FADD selectively kills normal but not cancerous prostate epithelial cells

The adaptor protein FADD directly, or indirectly via another adaptor called TRADD, recruits caspase 8 to death receptors of the tumor necrosis factor receptor family. Consequentially, a dominant-negative mutant (FADD-DN, which consists only of the FADD death domain) that binds to receptors but cannot recruit caspase 8 has been widely used to inhibit apoptosis by various stimuli that work via death receptors. Here, we show that FADD-DN also has another cell type- and cancer-dependent activity because it induces apoptosis of normal human prostate epithelial cells but not normal prostate stromal cells or prostate cancer cells. This activity is independent of FADD-DN's ability to bind to three known interacting proteins, Fas, TRADD or RIP suggesting that it is distinct from FADD's functions at activated death receptors. FADD-DN induces caspase activation in normal epithelial cells as demonstrated using a Fluorescence Resonance Energy Transfer assay that measures caspase activity in individual living cells. However, caspase-independent pathways are also implicated in FADD-DN-induced apoptosis because caspase inhibitors were inefficient at preventing prostate cell death. Therefore, the death domain of FADD has a previously unrecognized role in cell survival that is epithelial-specific and defective in cancer cells. This FADD-dependent signaling pathway may be important in prostate carcinogenesis.

Prophylactic salpingectomy does not impair the ovarian response in IVF treatment

To examine the effect of prophylactic salpingectomy in patients with hydrosalpinges on the ovarian response to stimulation prior to IVF, 26 patients were included in a study in which they acted as their own controls. They were all part of a randomized controlled study, in which they had been randomized to no surgical intervention prior to IVF. After one or two failed cycles, they underwent laparoscopic uni- or bilateral salpingectomy of their diseased tubes. The cycles before and after surgery were compared and the ovarian response was assessed as the dose and duration of gonadotrophins and the number of retrieved and fertilized oocytes. There were no significant differences in any of the measured outcomes. The increasing age between cycles did not influence the ovarian response, assessed by a comparison with two matched control groups from the same original study; 46 patients salpingectomized before IVF and 25 patients without surgery. It is concluded that removal of hydrosalpinx as a prophylactic laparoscopic procedure does not compromise ovarian function.

Student learning through video assessment

This paper reports on the use of video and self-assessment as a tool to guide and support undergraduate students in the practice of nursing. This method of learning and assessment promoted self- and peer evaluation as well as critical thinking. It encouraged students to take more responsibility for their learning and assisted academic staff and students to identify learning issues associated with clinical practices. Evaluative comments by teachers, students and educational experts have established the credibility and continued use of this approach within the Bachelor of Nursing program at a major university in Sydney, Australia.

The association of atopic dermatitis in infancy with immunoglobulin E food sensitization

OBJECTIVE

To prospectively investigate the association of high levels of immunoglobulin E (IgE) sensitization to foods and the presence of atopic dermatitis (judged by reported topical steroid use during the first 16 months of life) in a birth cohort of 620 Australian children "at risk" of allergic disease because of family history.

RESULTS

A total of 559 of the children in the cohort were fully evaluated, and the cumulative prevalence of atopic dermatitis was 24%. More children in the cohort who had atopic dermatitis had strongly positive skin test results (> or = 4+, histamine equivalent units, > or = approximately 6-mm wheal), consistent with IgE food sensitization to either cow's milk, egg, or peanut at 6 months (22% vs 5%, chi(2) = 35; P < 10(-6)) and at 12 months (36% vs 11%, chi(2) = 41; P < 10(-6)) than those without atopic dermatitis. The calculated attributable risk percent for IgE food sensitization as a cause of atopic dermatitis was 65% and 64% at these times. In a separate group of infants with severe atopic dermatitis, the equivalent rates of IgE food sensitization at 6 months was 83% and at 12 months, 65%.

CONCLUSION

IgE food sensitization is a major risk factor for the presence of atopic dermatitis in infancy.

The educational needs of part time clinical facilitators

Clinical facilitators play an important role in the clinical practicum component of an undergraduate nursing programme. Part time teachers are often employed in this role, however very little has been written about the needs of these facilitators. An exploratory study design incorporating focus group interviews and questionnaires was used to identify the needs of clinical facilitators at a large Australian university. This study showed that they are committed nurses who often feel inadequate in a role they feel lacks support and identity. The findings of the study have implications for the preparation of clinical facilitators.

A simplified ultrasound based infertility investigation protocol and its implications for patient management

PURPOSE

To evaluate whether a simplified infertility investigation protocol, focusing on the use of hysterocontrast sonography (HyCoSy), one blood test, and a semen analysis, would be sufficient as an initial screening test to select couples for specific treatment.

METHODS

The infertile couples underwent gynaecological examination, cervical sampling for cytology and Chlamydia trachomatis culture, B-mode transvaginal ultrasonography and basic hormonal analyses followed by a HyCoSy, and a semen analysis. A preliminary diagnosis was made for all patients. A management plan for treatment was suggested when possible; otherwise further examinations were recommended. The data were stored for later analysis and the routine investigation protocol was then adhered to and a final diagnosis and treatment were decided upon.

RESULTS

Agreement between the diagnosis based on HyCoSy and our routine protocol was present in 74% of cases (N = 73). In 13% (N = 13) there was partial agreement. In 36% the HyCoSy based protocol was considered sufficient to suggest treatment.

CONCLUSIONS

A simplified approach may lead to a significant reduction in both the time and cost of investigating an infertile couple.

Hydrosalpinx and IVF outcome: a prospective, randomized multicentre trial in Scandinavia on salpingectomy prior to IVF

Many retrospective studies have shown that hydrosalpinx is associated with poor in-vitro fertilization (IVF) outcome. The mechanism of the actual cause is not yet fully understood. A clinical practice of performing salpingectomy before IVF has developed, without any evidence from prospective trials. The aim of the present prospective randomized trial was to test if a salpingectomy prior to IVF was effective in terms of increased pregnancy rates. Patients with hydrosalpinx were randomized to either a laparoscopic salpingectomy or no intervention before IVF. A total of 204 patients was available for an intention-to-treat analysis and 192 actually started IVF. Clinical pregnancy rates per included patient were 36.6% in the salpingectomy group and 23.9% in the non-intervention group (not significant, P = 0.067) and the ensuing delivery rates were 28.6% and 16.3% (P = 0.045). The corresponding delivery rates per transfer cycle were 29.5% versus 17. 5% (not significant, P = 0.083). A subgroup analysis revealed significant differences in favour of salpingectomy, in implantation rates in patients with bilateral hydrosalpinges (25.6% versus 12.3%, P = 0.038) and in clinical pregnancy rates (45.7% versus 22.5%, P = 0.029) and delivery rates (40.0% versus 17.5%, P = 0.038) in patients with ultrasound visible hydrosalpinges. The delivery rate was increased 3.5-fold in patients with bilateral hydrosalpinges visible on ultrasound (P = 0.019).

The assessment of endometrial pathology and tubal patency: a comparison between the use of ultrasonography and X-ray hysterosalpingography for the investigation of infertility patients

OBJECTIVES

The aim of the present study was to examine the role of hysterosalpingocontrast sonography (HyCoSy) as a screening test for endometrial and tubal pathology at the start of the infertility investigation protocol.

METHODS

HyCoSy was compared with X-ray hysterosalpingography (HSG) for the assessment of the endometrial cavity and Fallopian tube patency. A total of 103 women with a history of at least 1 year's infertility were included. Each woman underwent both HyCoSy and HSG on the same day. Laparoscopy was performed in 43 cases. For HyCoSy examinations, saline was used for evaluation of the endometrial cavity and Echovist contrast medium to assess Fallopian tube patency.

RESULTS

The concordance between HyCoSy and HSG for the presence of endometrial cavity pathology was 90%, but for tubal patency the concordance was lower (72%). HyCoSy classed more examinations of tubal patency as uncertain. HSG more frequently classified tubes as occluded. In the subset of patients in whom all three techniques were used, HSG and HyCoSy demonstrated a high concordance with laparoscopy (83% and 80%, respectively). The prevalence of occluded tubes according to laparoscopy as the reference standard was 13%. The two methods had a high negative predictive value for tubal disease (HSG, 94%; HyCoSy, 88%), and the positive predictive values were 47% and 75%, respectively. The detection rate for occluded tubes was 73% and 27%, and specificity 87% and 90%, respectively.

CONCLUSIONS

Our data demonstrate that HyCoSy obtains similar information about the status of the endometrial cavity and Fallopian tube patency to that of HSG. It is possible that in some cases HyCoSy may replace HSG in order to select women with patent tubes who may be suitable for further infertility treatment without more invasive investigation.

Cell density and contraction regulate p38 MAP kinase-dependent responses in neonatal rat cardiac myocytes

In vitro cardiac myocyte hypertrophy is characterized by increased cell size, sarcomere organization, and induction of several genes including atrial natriuretic factor (ANF). The hypertrophic growth program has been associated with activation of various mitogen-activated protein kinase (MAP) kinase family members, one of which is a stress kinase, p38. In this study, we found that the p38-specific inhibitor SB-203580 failed to inhibit phenylephrine-induced ANF-driven gene expression in low-density myocyte cultures but did inhibit gene expression in higher density cultures. Dense myocyte cultures also had a higher metabolic activity and contraction rate than cells plated at low density. We found that mimicking this effect by rapid electrical pacing activated ANF-driven gene expression and that this expression was inhibited by inactivation of p38. However, addition of SB-203580 at time points ranging between 1 and 72 h suggests that the effect of p38 on the ANF promoter may be both direct and indirect. Electrical pacing induced a small, but consistent, increase in p38 phosphorylation (phospho-p38) at time points ranging from 30 min to 4 h, but at later times phospho-p38 levels were reduced. When myocytes were treated with phenylephrine or electrically paced in the presence of the p38 inhibitor, there was little discernible change in morphology or rates of protein synthesis from DMSO-treated cells at 48 or 72 h. These data indicate that cell density and myocyte contraction may modulate p38-dependent pathways for ANF gene expression, but these pathways may not be direct and have limited effects on hypertrophic morphology.

A low-affinity serum response element allows other transcription factors to activate inducible gene expression in cardiac myocytes

Hypertrophic growth of cardiac muscle cells is induced by a variety of physiological and pathological stimuli and is associated with a number of changes, including activation of genes such as atrial natriuretic factor. We found that two serum response element (SRE)-like DNA elements, one of which does not meet the consensus sequence and binds serum response factor (SRF) with low affinity, regulate the activity of this promoter. Surprisingly, the ability to induce the promoter by two different physiologic stimuli, as well as various activated transcription factors, including SRF-VP16, was primarily dependent upon the nonconsensus rather than the consensus SRE. This SRE controls the induction of gene expression via an unusual mechanism in that it is required to allow some, but not all, active transcription factors at unrelated sites on the promoter to stimulate gene expression. Thus, in addition to regulation of SRF activity by growth stimuli, regulation of a low-affinity SRE element controls inducible gene expression by modulating the ability of other transcription factors to stimulate the transcription machinery.

Risk factors for ectopic pregnancy in assisted reproduction

OBJECTIVE

To identify risk factors for ectopic pregnancy (EP) after IVF-ET.

DESIGN

Retrospective cohort study.

SETTING

In vitro fertilization clinic at a university hospital.

PATIENT(S)

A total of 725 women who conceived after IVF were studied with regard to background factors, indications for IVF, and factors related to the IVF procedure through review of their medical charts. The rate of EP was 4%, corresponding with 29 EPs, of which 2 were heterotopic.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Pregnancy outcome, defined as intrauterine pregnancy or EP. Background factors, indications for IVF, and factors related to the IVF procedure were analyzed for possible correlation with the outcome of EP. Risk factors for EP were identified by logistic regression analysis.

RESULT(S)

Tubal factor infertility, various previous abdominal surgeries, previous EP or pelvic infection, presence of a hydrosalpinx or fibroid, and type of transfer catheter used showed a positive correlation with EP as outcome. Logistic regression analysis identified two factors with predictive power: tubal factor infertility and previous myomectomy.

CONCLUSION(S)

Tubal factor infertility was the most prominent risk factor for EP after IVF. Previous myomectomy appeared to be another important risk factor, but this is a new finding that needs to be confirmed by further study.

Hydrosalpinx fluid does not adversely affect the normal development of human embryos and implantation in vitro

Several retrospectively designed studies have shown an association between the presence of hydrosalpinx and impaired implantation and pregnancy rates among in-vitro fertilization (IVF) patients. In the present study we have evaluated the influence of hydrosalpinx fluid on normal human embryo development and implantation. Surplus, donated frozen embryos (n = 183) from IVF patients were used to study the effects on blastocyst development of hydrosalpinx fluid at concentrations of 50 and 100% compared with controls in S2 medium. The fluids were analysed for concentrations of electrolytes, osmolarity, protein content, endotoxin levels, bacterial or fungal contamination, pH and haemoglobin content. There was no difference in blastocyst development in cultures under mineral oil when control cultures (15/42 = 36%) were compared with cultures in 50% hydrosalpinx fluid (32/96 = 33%). The only biochemical parameter which correlated with capacity for blastocyst development was pH in hydrosalpinx fluid/medium (50/50%) after equilibration in 5% CO2 in air. When embryos were cultured in 100% hydrosalpinx fluid the blastocyst development was 14% (5/36) in comparison to control 33% (3/9). The original experiment was repeated in an open culture system without the protection of mineral oil but still in the presence of 50% hydrosalpinx fluid. The rate of blastocyst development was within the same range in the open system. In three separate experiments, the capability of expanded blastocyst to implant on multilayer artificial endometrium was tested. In these experiments, 1/3, 4/5 and 9/9 blastocysts implanted. The present study demonstrates that hydrosalpinx fluid does not generally exert any major negative effects on in-vitro development of human embryos or on the implantation process in vitro.

Membrane-targeting sequences on AKAP79 bind phosphatidylinositol-4, 5-bisphosphate

Protein kinases and phosphatases are targeted through association with anchoring proteins that tether the enzymes to subcellular structures and organelles. Through in situ fluorescent techniques using a Green Fluorescent Protein tag, we have mapped membrane-targeting domains on AKAP79, a multivalent anchoring protein that binds the cAMP-dependent protein kinase (PKA), protein kinase C (PKC) and protein phosphatase 2B, calcineurin (CaN). Three linear sequences termed region A (residues 31-52), region B (residues 76-101) and region C (residues 116-145) mediate targeting of AKAP79 in HEK-293 cells and cortical neurons. Analysis of these targeting sequences suggests that they contain putative phosphorylation sites for PKA and PKC and are rich in basic and hydrophobic amino acids similar to a class of membrane-targeting domains which bind acidic phospholipids and calmodulin. Accordingly, the AKAP79 basic regions mediate binding to membrane vesicles containing acidic phospholipids including phosphatidylinositol-4, 5-bisphosphate [PtdIns(4,5)P2] and this binding is regulated by phosphorylation and calcium-calmodulin. Finally, AKAP79 was shown to be phosphorylated in HEK-293 cells following stimulation of PKA and PKC, and activation of PKC or calmodulin was shown to release AKAP79 from membrane particulate fractions. These findings suggest that AKAP79 might function in cells not only as an anchoring protein but also as a substrate and effector for the anchored kinases and phosphatases.

Treatment, failures and complications of ectopic pregnancy: changes over a 20 year period

Data from all 225 women operated on for ectopic pregnancy in 1992-1994 at Sahlgrenska University Hospital were collected and compared with three previous cross-sectional investigations from our hospital (1975-1979, 1981-1982 and 1986-1987) in order to evaluate the extent to which surgical treatment and post-operative complications have changed over a 20 year period. Laparoscopic surgery, which was not possible in the 1970s, was used in almost 85% of the ectopic pregnancies in 1992-1994. Conservative treatment was still the most frequently used technique. The complication rate was 1.2% in 1975-1979 when only laparotomies were carried out. After the introduction of laparoscopic surgery (1986-1987), the complication rate rose significantly (7.3%) and continued to increase even when this procedure was established as routine (14.2% in 1992-1994). Post-operative complications were most frequent after conservative laparoscopic surgery (24.4%) while there were no complications after laparotomies. In spite of increasing complication rates the frequency of patients in pre-shock, as well as the proportion of patients with heavy intra-abdominal bleeding and tubal rupture, decreased over time.

MAP kinase- and Rho-dependent signals interact to regulate gene expression but not actin morphology in cardiac muscle cells

Post-natal growth of cardiac muscle cells occurs by hypertrophy rather than division and is associated with changes in gene expression and muscle fiber morphology. We show here that the protein kinase MEKK1 can induce reporter gene expression from the atrial natriuretic factor (ANF) promoter, a genetic marker that is activated during in vivo hypertrophy. MEKK1 induced both stress-activated protein kinase (SAPK) and extracellular signal-regulated protein kinase (ERK) activity; however, while the SAPK cascade stimulated ANF expression, activation of the ERK cascade inhibited expression. C3 transferase, a specific inhibitor of the small GTPase Rho, also inhibited both MEKK- and phenylephrine-induced ANF expression, indicating an additional requirement for Rho-dependent signals. Microinjection or transfection of C3 transferase into the same cells did not disrupt actin muscle fiber morphology, indicating that Rho-dependent pathways do not regulate actin morphology in cardiac muscle cells. While active MEKK1 was a potent activator of hypertrophic gene expression, this kinase did not induce actin organization and prevented phenylephrine-induced organization. These data suggest that multiple signals control hypertrophic phenotypes. Positive and negative signals mediated by parallel MAP kinase cascades interact with Rho-dependent pathways to regulate hypertrophic gene expression while other signals induce muscle fiber morphology in cardiac muscle cells.

Contribution of the sodium-calcium exchanger to contractions in immature rabbit ventricular myocytes

In immature cardiac myocytes, the sarcoplasmic reticulum is sparse. Thus, we hypothesized that sarcolemmal Ca2+ influx through Na(+)-Ca2+ exchange is the dominant mechanism for modulating intracellular Ca2+ during contractions in fetal and neonatal hearts. We measured Na(+)-Ca2+ exchange currents in neonatal and adult rabbit ventricular cells using a rapid solution switch into 0 mM external Na+. The current densities (mean +/- SEM) were larger in 8 neonatal cells than in 10 adult cells (5.4 +/- 1.38 versus 1.65 +/- 0.25 pA/pF). Intracellular Ca2+ transients after inhibiting the sarcoplasmic reticulum with ryanodine and thapsigargin were unchanged in 15 neonatal cells, but decreased in 15 adult cells to 78.9 +/- 5.6% of baseline. When the Ca2+ channels were also inhibited by adding nifedipine, Ca2+ transients from Na(+)-Ca2+ exchange were 30.0 +/- 3.5% of baseline in neonatal cells compared with 13.4 +/- 3.4% in adult cells. Simultaneous contractions were a larger percent of baseline in neonatal cells (85.7.6 +/- 6.4%) than in adult cells (78.9 +/- 5.6%) after inhibiting the sarcoplasmic reticulum, and were unmeasureable in many cells from both age groups after inhibiting the Ca2+ channels as well. The ratio of Na(+)-Ca2+ exchanger mRNA to sarcoplasmic reticulum Ca(2+)-ATPase mRNA levels decreased from 1.0 +/- 0.13 to 0.4 +/- 0.03 to 0.26 +/- 0.02 in fetal, neonatal and adult ventricles, respectively. These measurements were consistent with a dominant role for the Na(+)-Ca2+ exchanger in the immature heart.

Previous ectopic pregnancy should be considered a contraindication for microsurgery

BACKGROUND

To estimate the risk of subsequent ectopic pregnancy (EP) after tubal surgery, given that the woman becomes pregnant, by means of a logistic model, a retrospective study was initiated.

METHODS

During the period 1986-1990, 221 women with tubal infertility underwent microsurgery. Subsequent fertility was evaluated in 1991. Ninety women conceived, of whom 84 were included in the study (30 with EP and 54 with intra-uterine pregnancy as the only outcome). Clinical background factors of importance, surgical procedures used, scoring systems for tubal lesions, adnexal adhesions and risk of EP were analysed for possible correlation to subsequent EP. These factors were further used in a logistic model to estimate the risk of subsequent EP as only outcome.

RESULTS

The risk of EP after microsurgery is minimum 15% without any risk factors. Previous EP and endometriosis could be identified as factors with prognostic power in the logistic model. One previous EP implies a 60% risk, whereas two previous EPs and endometriosis increase the risk to 95%.

CONCLUSION

Patients with previous EP should generally not be considered for microsurgery owing to the high risk of recurrence and to the reduced chance of intra-uterine pregnancy.

[Ectopic pregnancy. The "epidemic" seems to be over]

Since decades the incidence of ectopic pregnancy has risen in most western countries including four to five folded increased rates, suggesting an "epidemic". Increasing incidences of ectopic pregnancy was reported in Sweden until 1988 and 1989 when a peak of 17.3 cases of ectopic pregnancy/10,000 women in fertile age was registered. Between 1990 and 1991 the incidence decreased from 16.8 to 14.9 cases of ectopic pregnancy/10,000 women. The mortality in Sweden 1985-1991 was 0.15/1000 (3 deaths in 20,486 cases of ectopic pregnancy), the lowest case-fatality rate ever reported.