Safety of Ancestral Monovalent BNT162b2, mRNA-1273, and NVX-CoV2373 COVID-19 Vaccines in US Children Aged 6 Months to 17 Years.

Importance: Active monitoring of health outcomes after COVID-19 vaccination provides early detection of rare outcomes that may not be identified in prelicensure trials. Objective: To conduct near-real-time monitoring of health outcomes after COVID-19 vaccination in the US pediatric population. Design, Setting, and Participants: This cohort study evaluated 21 prespecified health outcomes after exposure before early 2023 to BNT162b2, mRNA-1273, or NVX-CoV2373 ancestral monovalent COVID-19 vaccines in children aged 6 months to 17 years by applying a near-real-time monitoring framework using health care data from 3 commercial claims databases in the US (Optum [through April 2023], Carelon Research [through March 2023], and CVS Health [through February 2023]). Increased rates of each outcome after vaccination were compared with annual historical rates from January 1 to December 31, 2019, and January 1 to December 31, 2020, as well as between April 1 and December 31, 2020. Exposure: Receipt of an ancestral monovalent BNT162b2, mRNA-1273, or NVX-CoV2373 COVID-19 vaccine dose identified through administrative claims data linked with Immunization Information Systems data. Main Outcomes and Measures: Twenty-one prespecified health outcomes, of which 15 underwent sequential testing and 6 were only monitored descriptively due to lack of historical rates. Results: Among 4 102 016 vaccinated enrollees aged 6 months to 17 years, 2 058 142 (50.2%) were male and 3 901 370 (95.1%) lived in an urban area. Thirteen of 15 sequentially tested outcomes did not meet the threshold for a statistical signal. Statistical signals were detected for myocarditis or pericarditis after BNT162b2 vaccination in children aged 12 to 17 years and seizure after vaccination with BNT162b2 and mRNA-1273 in children aged 2 to 4 or 5 years. However, in post hoc sensitivity analyses, a statistical signal for seizure was observed only after mRNA-1273 when 2019 background rates were selected; no statistical signal was observed when 2022 rates were selected. Conclusions and Relevance: In this cohort study of pediatric enrollees across 3 commercial health insurance databases, statistical signals detected for myocarditis or pericarditis after BNT162b2 (ages 12-17 years) were consistent with previous reports, and seizures after BNT162b2 (ages 2-4 years) and mRNA-1273 vaccinations (ages 2-5 years) should be further investigated in a robust epidemiologic study with confounding adjustment. The US Food and Drug Administration concludes that the known and potential benefits of COVID-19 vaccination outweigh the known and potential risks of COVID-19 infection.

Severe Hypocalcemia With Denosumab Among Older Female Dialysis-Dependent Patients.

Importance: Dialysis-dependent patients experience high rates of morbidity from fractures, yet little evidence is available on optimal treatment strategies. Chronic kidney disease-mineral and bone disorder is nearly universal in dialysis-dependent patients, complicating diagnosis and treatment of skeletal fragility. Objective: To examine the incidence and comparative risk of severe hypocalcemia with denosumab compared with oral bisphosphonates among dialysis-dependent patients treated for osteoporosis. Design, Setting, and Participants: Retrospective cohort study of female dialysis-dependent Medicare patients aged 65 years or older who initiated treatment with denosumab or oral bisphosphonates from 2013 to 2020. Clinical performance measures including monthly serum calcium were obtained through linkage to the Consolidated Renal Operations in a Web-Enabled Network database. Exposures: Denosumab, 60 mg, or oral bisphosphonates. Main Outcomes and Measures: Severe hypocalcemia was defined as total albumin-corrected serum calcium below 7.5 mg/dL (1.88 mmol/L) or a primary hospital or emergency department hypocalcemia diagnosis (emergent care). Very severe hypocalcemia (serum calcium below 6.5 mg/dL [1.63 mmol/L] or emergent care) was also assessed. Inverse probability of treatment-weighted cumulative incidence, weighted risk differences, and weighted risk ratios were calculated during the first 12 treatment weeks. Results: In the unweighted cohorts, 607 of 1523 denosumab-treated patients and 23 of 1281 oral bisphosphonate-treated patients developed severe hypocalcemia. The 12-week weighted cumulative incidence of severe hypocalcemia was 41.1% with denosumab vs 2.0% with oral bisphosphonates (weighted risk difference, 39.1% [95% CI, 36.3%-41.9%]; weighted risk ratio, 20.7 [95% CI, 13.2-41.2]). The 12-week weighted cumulative incidence of very severe hypocalcemia was also increased with denosumab (10.9%) vs oral bisphosphonates (0.4%) (weighted risk difference, 10.5% [95% CI, 8.8%-12.0%]; weighted risk ratio, 26.4 [95% CI, 9.7-449.5]). Conclusions and Relevance: Denosumab was associated with a markedly higher incidence of severe and very severe hypocalcemia in female dialysis-dependent patients aged 65 years or older compared with oral bisphosphonates. Given the complexity of diagnosing the underlying bone pathophysiology in dialysis-dependent patients, the high risk posed by denosumab in this population, and the complex strategies required to monitor and treat severe hypocalcemia, denosumab should be administered after careful patient selection and with plans for frequent monitoring.

Risk of Severe COVID-19 in Prevalent Users of Alpha-1 Adrenergic Receptor Antagonists: A National Case-Control Study of Medicare Beneficiaries.

BACKGROUND: Alpha-1 adrenergic receptor antagonists prevent cytokine storm in mouse sepsis models. This led to the hypothesis that alpha-1 blockers may prevent severe coronavirus disease 2019 (COVID-19), which is characterized by hypercytokinemia and progressive respiratory failure. METHODS: We performed an observational case-control study in male Medicare beneficiaries aged 65 years or older, with or without benign prostatic hyperplasia (BPH), and treated with alpha-1 receptor blockers or 5-alpha reductase inhibitors. Adjusted odds ratios (aOR) and 95% confidence intervals (CI) were estimated for outcomes of uncomplicated and severe COVID-19 hospitalization (intensive care unit admission, invasive mechanical ventilation, or death). RESULTS: There were 20,963 cases of hospitalized COVID-19 matched to 101,161 controls on calendar date and neighborhood of residence. In the primary analysis (males with BPH), there was no difference in risk of uncomplicated COVID-19 hospitalization (aOR 1.08, 95% CI 0.996-1.17) or hospitalization with severe complications (aOR 0.97, 95% CI 0.88-1.08). In the secondary analysis (males with or without BPH), the corresponding aORs were 1.02 (95% CI, 0.96-1.09) (uncomplicated) and 0.99 (95% CI, 0.91-1.07) (complicated), respectively. Subgroup and sensitivity analyses yielded similar results. Of note, there was no difference in risk of severe COVID-19 hospitalization when comparing non-selective vs selective alpha-1 blocker use (aOR 0.98, 95% CI 0.86-1.10), higher- vs lower-dose alpha-1 blocker use (aOR 0.96, 95% CI 0.86-1.08), or current vs remote alpha-1 blocker use (aOR 1.04, 95% CI 0.91-1.18). CONCLUSIONS: Prevalent use of alpha-1 receptor blockers was not associated with a protective or harmful effect on risk of uncomplicated or severe hospitalized COVID-19.

Safety of the BNT162b2 COVID-19 Vaccine in Children Aged 5 to 17 Years.

Importance: Active monitoring of health outcomes after COVID-19 vaccination offers early detection of rare outcomes that may not be identified in prelicensure trials. Objective: To conduct near-real-time monitoring of health outcomes following BNT162b2 COVID-19 vaccination in the US pediatric population aged 5 to 17 years. Design, Setting, and Participants: This population-based study was conducted under a public health surveillance mandate from the US Food and Drug Administration. Participants aged 5 to 17 years were included if they received BNT162b2 COVID-19 vaccination through mid 2022 and had continuous enrollment in a medical health insurance plan from the start of an outcome-specific clean window until the COVID-19 vaccination. Surveillance of 20 prespecified health outcomes was conducted in near real time within a cohort of vaccinated individuals from the earliest Emergency Use Authorization date for the BNT162b2 vaccination (December 11, 2020) and was expanded as more pediatric age groups received authorization through May and June 2022. All 20 health outcomes were monitored descriptively, 13 of which additionally underwent sequential testing. For these 13 health outcomes, the increased risk of each outcome after vaccination was compared with a historical baseline with adjustments for repeated looks at the data as well as a claims processing delay. A sequential testing approach was used, which declared a safety signal when the log likelihood ratio comparing the observed rate ratio against the null hypothesis exceeded a critical value. Exposure: Exposure was defined as receipt of a BNT162b2 COVID-19 vaccine dose. The primary analysis assessed primary series doses together (dose 1 + dose 2), and dose-specific secondary analyses were conducted. Follow-up time was censored for death, disenrollment, end of the outcome-specific risk window, end of the study period, or a receipt of a subsequent vaccine dose. Main Outcomes: Twenty prespecified health outcomes: 13 were assessed using sequential testing and 7 were monitored descriptively because of a lack of historical comparator data. Results: This study included 3 017 352 enrollees aged 5 to 17 years. Of the enrollees across all 3 databases, 1 510 817 (50.1%) were males, 1 506 499 (49.9%) were females, and 2 867 436 (95.0%) lived in an urban area. In the primary sequential analyses, a safety signal was observed only for myocarditis or pericarditis after primary series vaccination with BNT162b2 in the age group 12 to 17 years across all 3 databases. No safety signals were observed for the 12 other outcomes assessed using sequential testing. Conclusions and Relevance: Among 20 health outcomes that were monitored in near real time, a safety signal was identified for only myocarditis or pericarditis. Consistent with other published reports, these results provide additional evidence that COVID-19 vaccines are safe in children.

Listening to a popular upbeat song can lead to more adaptive cognitive inferences for stressful events in non-clinical adult populations.

OBJECTIVE: We tested the effect of music on idiographic cognitive inferences about stressful events. METHOD: In Study 1 (n = 336), adult participants from the United States were randomly assigned to non-familiar songs that differed by lyrical content and tempo. In Studies 2 (n = 302) and 3 (n = 323), adult participants from the United States were randomly assigned to either a positive, neutral or no-song condition. RESULTS: The results of Study 1 failed to support any of the study hypotheses. Given the null results, we decided to conduct a second study focused on increasing external validity and power (i.e., including fewer experimental conditions). The results of Study 2 showed that adults randomly assigned to a familiar upbeat song condition experienced an increase in positive affect and a decrease in event-specific negative cognitions. A third study was then conducted to replicate the results and rule out a potential confound. Results of Study 3 corroborated the results of Study 2. CONCLUSION: Taken together (Studies 2 and 3), results indicate it may be useful for future research to test the extent to which familiar upbeat music can be helpful during cognitive restructuring activities in psychotherapy to nudge people to generate more adaptive cognitions.

Cell death in cancer chemotherapy using taxanes.

Cancer cells evolve to be refractory to the intrinsic programmed cell death mechanisms, which ensure cellular tissue homeostasis in physiological conditions. Chemotherapy using cytotoxic drugs seeks to eliminate cancer cells but spare non-cancerous host cells by exploring a likely subtle difference between malignant and benign cells. Presumably, chemotherapy agents achieve efficacy by triggering programmed cell death machineries in cancer cells. Currently, many major solid tumors are treated with chemotherapy composed of a combination of platinum agents and taxanes. Platinum agents, largely cis-platin, carboplatin, and oxaliplatin, are DNA damaging agents that covalently form DNA addicts, triggering DNA repair response pathways. Taxanes, including paclitaxel, docetaxel, and cabazitaxel, are microtubule stabilizing drugs which are often very effective in purging cancer cells in clinical settings. Generally, it is thought that the stabilization of microtubules by taxanes leads to mitotic arrest, mitotic catastrophe, and the triggering of apoptotic programmed cell death. However, the precise mechanism(s) of how mitotic arrest and catastrophe activate the caspase pathway has not been established. Here, we briefly review literature on the involvement of potential cell death mechanisms in cancer therapy. These include the classical caspase-mediated apoptotic programmed cell death, necroptosis mediated by MLKL, and pore forming mechanisms in immune cells, etc. In particular, we discuss a newly recognized mechanism of cell death in taxane-treatment of cancer cells that involves micronucleation and the irreversible rupture of the nuclear membrane. Since cancer cells are commonly retarded in responding to programmed cell death signaling, stabilized microtubule bundle-induced micronucleation and nuclear membrane rupture, rather than triggering apoptosis, may be a key mechanism accounting for the success of taxanes as anti-cancer agents.

Paclitaxel resistance related to nuclear envelope structural sturdiness.

Taxanes (Taxol/paclitaxel, Docetaxel/taxotere) are a key group of successful drugs commonly used in chemotherapy to treat several major malignant tumors also as a front-line agent in combination with carboplatin/cisplatin, as well as a second line drug with a dose dense regimen following recurrence. Overall, the response to paclitaxel is excellent, though drug resistance inevitably develops in subsequent treatments. The commonly accepted mechanism of action is that the hindrance of microtubule function by paclitaxel leads to cell cycle arrest at mitosis, and subsequent apoptosis. The mechanisms for resistance to paclitaxel have also been extensively investigated, such as ABC transporter overexpression, altered signaling and apoptotic gene expression to resist cell death, and changes associated with microtubules to reduce influences of the drugs. Meanwhile, another important mechanism of paclitaxel resistance has been proposed: increased nuclear lamina/envelope sturdiness to retard the breaking of nuclear envelop and the paclitaxel-induced multinucleation as well as the formation of multiple micronuclei. Here in this review, we focus on experimental findings and ideas on the mechanism of paclitaxel resistance related to cancer nuclear envelope, to provide new insights on overcoming paclitaxel resistance.

Rationale for combination of paclitaxel and CDK4/6 inhibitor in ovarian cancer therapy - non-mitotic mechanisms of paclitaxel.

Taxanes and CDK4/6 inhibitors (CDK4/6i) are two families of successful anti-mitotic drugs used in the treatment of solid tumors. Paclitaxel, representing taxane compounds, has been used either alone or in combination with other agents (commonly carboplatin/cisplatin) in the treatment of many solid tumors including ovarian, breast, lung, prostate cancers, and Kaposi's sarcoma. Paclitaxel has been routinely prescribed in cancer treatment since the 1990s, and its prominent role is unlikely to be replaced in the foreseeable future. Paclitaxel and other taxanes work by binding to and stabilizing microtubules, causing mitotic arrest, aberrant mitosis, and cell death. CDK4/6i (palbociclib, ribociclib, abemaciclib) are relatively new cell cycle inhibitors that have been found to be effective in breast cancer treatment, and are currently being developed in other solid tumors. CDK4/6i blocks cell cycle progression at the G1 phase, resulting in cell death by mechanisms not yet fully elucidated. At first glance, paclitaxel and CDK4/6i are unlikely synergistic agents as both are cell cycle inhibitors that work at different phases of the cell cycle, and few clinical trials have yet considered adding CDK4/6i to existing paclitaxel chemotherapy. However, recent findings suggest the importance of a non-mitotic mechanism of paclitaxel in cancer cell death and pre-clinical data support rationale for a strategic paclitaxel and CDK4/6i combination. In mouse tumor model studies, drug sequencing resulted in differential efficacy, indicating complex biological interactions of the two drugs. This article reviews the rationales of combining paclitaxel with CDK4/6i as a potential therapeutic option in recurrent ovarian cancer.

Near real-time surveillance of safety outcomes in US COVID-19 vaccine recipients aged 12 to 64 years.

BACKGROUND: Active monitoring of safety outcomes following COVID-19 vaccination is critical to understand vaccine safety and can provide early detection of rare outcomes not identified in pre-licensure trials. We present findings from an early warning rapid surveillance system in three large commercial insurance databases including more than 16 million vaccinated individuals. METHODS: We evaluated 17 outcomes of interest following COVID-19 vaccination among individuals aged 12-64 years in Optum, HealthCore, and CVS Health databases from December 11, 2020, through January 22, 2022, January 7, 2022, and December 31, 2021, respectively. We conducted biweekly or monthly sequential testing and generated rate ratios (RR) of observed outcome rates compared to historical (or expected) rates prior to COVID-19 vaccination. FINDINGS: Among 17 outcomes evaluated, 15 did not meet the threshold for statistical signal in any of the three databases. Myocarditis/pericarditis met the statistical threshold for a signal following BNT162b2 in two of three databases (RRs: 1.83-2.47). Anaphylaxis met the statistical threshold for a signal in all three databases following BNT162b2 vaccination (RRs: 4.48-10.86) and mRNA-1273 vaccination (RRs: 7.64-12.40). DISCUSSION: Consistent with published literature, our near-real time monitoring of 17 adverse outcomes following COVID-19 vaccinations identified signals for myocarditis/pericarditis and anaphylaxis following mRNA COVID-19 vaccinations. The method is intended for early detection of safety signals, and results do not imply a causal effect. Results of this study should be interpreted in the context of the method's utility and limitations, and the validity of detected signals must be evaluated in fully adjusted epidemiologic studies.

Low Intensity Ultrasound as an Antidote to Taxane/Paclitaxel-induced Cytotoxicity.

The taxane family of compounds, including Taxol/paclitaxel and Taxotere/docetaxel, are surprisingly successful drugs used in combination or alone for the treatment of most major solid tumors, especially metastatic cancer. The drugs are commonly used in regimen with other agents (often platinum drugs) as frontline treatment, or used as a single agent in a dose dense regimen for recurrent cancer. The major side effects of taxanes are peripheral neuropathy, alopecia, and neutropenia, which are grave burden for patients and limit the full potential of the taxane drugs. Especially in the current treatment protocol for peripheral neuropathy, taxane dosage is reduced once the symptoms present, resulting in the loss of full or optimal cancer killing activity. Substantial efforts have been made to address the problem of cytotoxic side effects of taxanes, though strategies remain very limited. Following administration of the taxane compound by infusion, taxane binds to cellular microtubules and is sequestered within the cells for several days. Taxane stabilizes and interferes with microtubule function, leading to ultimate death of cancer cells, but also damages hair follicles, peripheral neurons, and hemopoietic stem cells. Currently, cryo-treatment is practiced to limit exposure and side effects of the drug during infusion, though the effectiveness is uncertain or limited. A recent laboratory finding may provide a new strategy to counter taxane cytotoxicity, that a brief exposure to low density ultrasound waves was sufficient to eliminate paclitaxel cytotoxicity cells in culture by transiently breaking microtubule filaments, which were then relocated to lysosomes for disposal. Thus, ultrasonic force to break rigid microtubules is an effective solution to counter taxane cytotoxicity. The discovery and concept of low intensity ultrasound as an antidote may have the potential to provide a practical strategy to counter paclitaxel-induced peripheral neuropathy and alopecia that resulted from chemotherapy. Taxanes are a class of important drugs used in chemotherapy to treat several major cancers. This article reviews a new laboratory discovery that ultrasound can be used as an antidote for the peripheral cytotoxicity of taxane drugs and discusses the potential development and application of low intensity ultrasound to prevent side effects in chemotherapeutic treatment of cancer patients.

Risk of Covid-19-Related Hospitalization and More Severe Outcomes in Medicare Beneficiaries Treated with Renin-Angiotensin-Aldosterone System Inhibitors for Hypertension.

BACKGROUND: There are theoretical concerns that angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) could increase the risk of severe Covid-19. OBJECTIVE: To determine if ACEIs and ARBs are associated with an increased risk of Covid-19 hospitalization overall, or hospitalization involving intensive care unit (ICU) admission, invasive mechanical ventilation, or death. DESIGN: Observational case-control study. PARTICIPANTS: Medicare beneficiaries aged ≥ 66 years with hypertension, treated with ACEIs, ARBs, calcium channel blockers (CCBs), or thiazide diuretics. MAIN MEASURES: Adjusted odds ratios (OR) and 95% confidence intervals (CI) for the outcomes of Covid-19 hospitalization, or hospitalization involving ICU admission, invasive mechanical ventilation, or death. RESULTS: A total of 35,300 cases of hospitalized Covid-19 were matched to 228,228 controls on calendar date and neighborhood of residence. The median age of cases was 79 years, 57.4% were female, and the median duration of hospitalization was 8 days (interquartile range 5-12). ACEIs and ARBs were associated with a slight reduction in Covid-19 hospitalization risk compared with treatment with other first-line antihypertensives (OR for ACEIs 0.95, 95% CI 0.92-0.98; OR for ARBs 0.94, 95% CI 0.90-0.97). Similar results were obtained for hospitalizations involving ICU admission, invasive mechanical ventilation, or death. There were no meaningful differences in risk for ACEIs compared with ARBs. In an analysis restricted to monotherapy with a first-line agent, CCBs were associated with a small increased risk of Covid-19 hospitalization compared with ACEIs (OR 1.09, 95% CI 1.04-1.14), ARBs (OR 1.10, 95% CI 1.05-1.15), or thiazide diuretics (OR 1.11, 95% CI 1.03-1.19). CONCLUSIONS: ACEIs and ARBs were not associated with an increased risk of Covid-19 hospitalization or with hospitalization involving ICU admission, invasive mechanical ventilation, or death. The finding of a small increased risk of Covid-19 hospitalization with CCBs was unexpected and could be due to residual confounding.

Exposure to low intensity ultrasound removes paclitaxel cytotoxicity in breast and ovarian cancer cells.

BACKGROUND: Paclitaxel (Taxol) is a microtubule-stabilizing drug used to treat several solid tumors, including ovarian, breast, non-small cell lung, and pancreatic cancers. The current treatment of ovarian cancer is chemotherapy using paclitaxel in combination with carboplatin as a frontline agent, and paclitaxel is also used in salvage treatment as a second line drug with a dose intensive regimen following recurrence. More recently, a dose dense approach for paclitaxel has been used to treat metastatic breast cancer with success. Paclitaxel binds to beta tubulin with high affinity and stabilizes microtubule bundles. As a consequence of targeting microtubules, paclitaxel kills cancer cells through inhibition of mitosis, causing mitotic catastrophes, and by additional, not yet well defined non-mitotic mechanism(s). RESULTS: In exploring methods to modulate activity of paclitaxel in causing cancer cell death, we unexpectedly found that a brief exposure of paclitaxel-treated cells in culture to low intensity ultrasound waves prevented the paclitaxel-induced cytotoxicity and death of the cancer cells. The treatment with ultrasound shock waves was found to transiently disrupt the microtubule cytoskeleton and to eliminate paclitaxel-induced rigid microtubule bundles. When cellular microtubules were labelled with a fluorescent paclitaxel analog, exposure to ultrasound waves led to the disassembly of the labeled microtubules and localization of the signals to perinuclear compartments, which were determined to be lysosomes. CONCLUSIONS: We suggest that ultrasound disrupts the paclitaxel-induced rigid microtubule cytoskeleton, generating paclitaxel bound fragments that undergo degradation. A new microtubule network forms from tubulins that are not bound by paclitaxel. Hence, ultrasound shock waves are able to abolish paclitaxel impact on microtubules. Thus, our results demonstrate that a brief exposure to low intensity ultrasound can reduce and/or eliminate cytotoxicity associated with paclitaxel treatment of cancer cells in cultures.

Nuclear Lamin A/C Expression Is a Key Determinant of Paclitaxel Sensitivity.

Paclitaxel is a key member of the Taxane (paclitaxel [originally named taxol], docetaxel/Taxotere) family of successful drugs used in the current treatment of several solid tumors, including ovarian cancer. The molecular target of paclitaxel has been identified as tubulin, and paclitaxel binding alters the dynamics and thus stabilizes microtubule bundles. Traditionally, the anticancer mechanism of paclitaxel has been thought to originate from its interfering with the role of microtubules in mitosis, resulting in mitotic arrest and subsequent apoptosis. However, recent evidence suggests that paclitaxel operates in cancer therapies via an as-yet-undefined mechanism rather than as a mitotic inhibitor. We found that paclitaxel caused a striking break up of nuclei (referred to as multimicronucleation) in malignant ovarian cancer cells but not in normal cells, and susceptibility to undergo nuclear fragmentation and cell death correlated with a reduction in nuclear lamina proteins, lamin A/C. Lamin A/C proteins are commonly lost, reduced, or heterogeneously expressed in ovarian cancer, accounting for the aberration of nuclear shape in malignant cells. Mouse ovarian epithelial cells isolated from lamin A/C-null mice were highly sensitive to paclitaxel and underwent nuclear breakage, compared to control wild-type cells. Forced overexpression of lamin A/C led to resistance to paclitaxel-induced nuclear breakage in cancer cells. Additionally, paclitaxel-induced multimicronucleation occurred independently of cell division that was achieved by either the withdrawal of serum or the addition of mitotic inhibitors. These results provide a new understanding for the mitotis-independent mechanism for paclitaxel killing of cancer cells, where paclitaxel induces nuclear breakage in malignant cancer cells that have a malleable nucleus but not in normal cells that have a stiffer nuclear envelope. As such, we identify that reduced nuclear lamin A/C protein levels correlate with nuclear shape deformation and are a key determinant of paclitaxel sensitivity of cancer cells.

Dynamic conversion of cell sorting patterns in aggregates of embryonic stem cells with differential adhesive affinity.

BACKGROUND: Mammalian early development comprises the proliferation, differentiation, and self-assembly of the embryonic cells. The classic experiment undertaken by Townes and Holtfreter demonstrated the ability of dissociated embryonic cells to sort and self-organize spontaneously into the original tissue patterns. Here, we further explored the principles and mechanisms underlying the phenomenon of spontaneous tissue organization by studying aggregation and sorting of mouse embryonic stem (ES) cells with differential adhesive affinity in culture. RESULTS: As observed previously, in aggregates of wild-type and E-cadherin-deficient ES cells, the cell assemblies exhibited an initial sorting pattern showing wild-type cells engulfed by less adhesive E-cadherin-deficient ES cells, which fits the pattern predicted by the differential adhesive hypothesis proposed by Malcom Steinberg. However, in further study of more mature cell aggregates, the initial sorting pattern reversed, with the highly adhesive wild-type ES cells forming an outer shell enveloping the less adhesive E-cadherin-deficient cells, contradicting Steinberg's sorting principle. The outer wild-type cells of the more mature aggregates did not differentiate into endoderm, which is known to be able to sort to the exterior from previous studies. In contrast to the naive aggregates, the mature aggregates presented polarized, highly adhesive cells at the outer layer. The surface polarity was observed as an actin cap contiguously spanning across the apical surface of multiple adjacent cells, though independent of the formation of tight junctions. CONCLUSIONS: Our experimental findings suggest that the force of differential adhesive affinity can be overcome by even subtle polarity generated from strong bilateral ligation of highly adhesive cells in determining cell sorting patterns.

Breaking malignant nuclei as a non-mitotic mechanism of taxol/paclitaxel.

Discovered in a large-scale screening of natural plant chemicals, Taxol/paclitaxel and the taxane family of compounds are surprisingly successful anti-cancer drugs, used in treatment of the majority of solid tumors, and especially suitable for metastatic and recurrent cancer. Paclitaxel is often used in combination with platinum agents and is administrated in a dose dense regimen to treat recurrent cancer. The enthusiasm and clinical development were prompted by the discovery that Taxol binds beta-tubulins specifically found within microtubules and stabilizes the filaments, and consequently inhibits mitosis. However, questions on how paclitaxel suppresses cancer persist, as other specific mitotic inhibitors are impressive in pre-clinical studies but fail to achieve significant clinical activity. Thus, additional mechanisms, such as promoting mitotic catastrophe and impacting non-mitotic targets, have been proposed and studied. A good understanding of how paclitaxel, and additional new microtubule stabilizing agents, kill cancer cells will advance the clinical application of these common chemotherapeutic agents. A recent study provides a potential non-mitotic mechanism of paclitaxel action, that paclitaxel-induced rigid microtubules act to break malleable cancer nuclei into multiple micronuclei. Previous studies have established that cancer cells have a less sturdy, more pliable nuclear envelope due to the loss or reduction of lamin A/C proteins. Such changes in nuclear structure provide a selectivity for paclitaxel to break the nuclear membrane and kill cancer cells over non-neoplastic cells that have a sturdier nuclear envelope. The formation of multiple micronuclei appears to be an important aspect of paclitaxel in the killing of cancer cells, either by a mitotic or non-mitotic mechanism. Additionally, by binding to microtubule, paclitaxel is readily sequestered and concentrated within cells. This unique pharmacokinetic property allows the impact of paclitaxel on cells to persist for several days, even though the circulating drug level is much reduced following drug administration/infusion. The retention of paclitaxel within cells likely is another factor contributing to the efficacy of the drugs. Overall, the new understanding of Taxol/paclitaxel killing mechanism-rigid microtubule-induced multiple micronucleation-will likely provide new strategies to overcome drug resistance and for rational drug combination.

Quality Improvement Intervention for Universal Lipid Screening in Children Aged 9 to 11 Years.

We performed a quality improvement intervention to increase universal lipid screening in well-child visits (age 9 to 11 years): 12-month preintervention; phase 1 (8 months) with provider education, group monthly chart review with feedback, and electronic health record cues to order lipids; and phase 2 (16 months) with electronic health record cues and examination room phlebotomy. Outcomes were compared with clinics having no intervention. In phase 1, immediate treatment effect on the regression line for provider behavior (proportion of visits with lipids ordered) showed 34% increase in intervention and 7% decrease in comparison clinics; patient behavior (phlebotomy completed) showed 19% increase in intervention and 5% decrease in comparison clinics. At the beginning of phase 2, the intervention clinic had average 44% orders entered and 33% phlebotomy completed per well-child visit, and these proportions were maintained. Provider education and chart review with feedback were associated with the greatest gains in outcomes.

Early-Onset Sepsis Risk Calculator Integration Into an Electronic Health Record in the Nursery.

BACKGROUND AND OBJECTIVES: An early-onset sepsis (EOS) risk calculator tool to guide evaluation and treatment of infants at risk for sepsis has reduced antibiotic use without increased adverse outcomes. We performed an electronic health record (EHR)-driven quality improvement intervention to increase calculator use for infants admitted to a newborn nursery and reduce antibiotic treatment of infants at low risk for sepsis. METHODS: This 2-phase intervention included programming (1) an EHR form containing calculator fields that were external to the infant's admission note, with nonautomatic access to the calculator, education for end-users, and reviewing risk scores in structured bedside rounds and (2) discrete data entry elements into the EHR admission form with a hyperlink to the calculator Web site. We used statistical process control to assess weekly entry of risk scores and antibiotic orders and interrupted time series to assess trend of antibiotic orders. RESULTS: During phase 1 (duration, 14 months), a mean 59% of infants had EOS calculator scores entered. There was wide variability around the mean, with frequent crossing of weekly means beyond the 3σ control lines, indicating special-cause variation. During phase 2 (duration, 2 years), mean frequency of EOS calculator use increased to 85% of infants, and variability around the mean was within the 3σ control lines. The frequency of antibiotic orders decreased from preintervention (7%) to the final 6 months of phase 2 (1%, P < .001). CONCLUSIONS: An EHR-driven quality improvement intervention increased EOS calculator use and reduced antibiotic orders, with no increase in adverse events.

Defective Nuclear Lamina in Aneuploidy and Carcinogenesis.

Aneuploidy, loss or gain of whole chromosomes, is a prominent feature of carcinomas, and is generally considered to play an important role in the initiation and progression of cancer. In high-grade serous ovarian cancer, the only common gene aberration is the p53 point mutation, though extensive genomic perturbation is common due to severe aneuploidy, which presents as a deviant karyotype. Several mechanisms for the development of aneuploidy in cancer cells have been recognized, including chromosomal non-disjunction during mitosis, centrosome amplification, and more recently, nuclear envelope rupture at interphase. Many cancer types including ovarian cancer have lost or reduced expression of Lamin A/C, a structural component of the lamina matrix that underlies the nuclear envelope in differentiated cells. Several recent studies suggest that a nuclear lamina defect caused by the loss or reduction of Lamin A/C leads to failure in cytokinesis and formation of tetraploid cells, transient nuclear envelope rupture, and formation of nuclear protrusions and micronuclei during the cell cycle gap phase. Thus, loss and reduction of Lamin A/C underlies the two common features of cancer-aberrations in nuclear morphology and aneuploidy. We discuss here and emphasize the newly recognized mechanism of chromosomal instability due to the rupture of a defective nuclear lamina, which may account for the rapid genomic changes in carcinogenesis.

New biological research and understanding of Papanicolaou's test.

The development of the Papanicolaou smear test by Dr. George Nicholas Papanicolaou (1883-1962) is one of the most significant achievements in screening for disease and cancer prevention in history. The Papanicolaou smear has been used for screening of cervical cancer since the 1950s. The test is technically straightforward and practical and based on a simple scientific observation: malignant cells have an aberrant nuclear morphology that can be distinguished from benign cells. Here, we review the scientific understanding that has been achieved and continues to be made on the causes and consequences of abnormal nuclear morphology, the basis of Dr. Papanicolaou's invention. The deformed nuclear shape is caused by the loss of lamina and nuclear envelope structural proteins. The consequences of a nuclear envelope defect include chromosomal numerical instability, altered chromatin organization and gene expression, and increased cell mobility because of a malleable nuclear envelope. HPV (Human Papilloma Virus) infection is recognized as the key etiology in the development of cervical cancer. Persistent HPV infection causes disruption of the nuclear lamina, which presents as a change in nuclear morphology detectable by a Papanicolaou smear. Thus, the causes and consequences of nuclear deformation are now linked to the mechanisms of viral carcinogenesis, and are still undergoing active investigation to reveal the details. Recently a statue was installed in front of the Papanicolaou's Cancer Research Building to honor the inventor. Remarkably, the invention nearly 60 years ago by Dr. Papanicolaou still exerts clinical impacts and inspires scientific inquiries.

GATA6 phosphorylation by Erk1/2 propels exit from pluripotency and commitment to primitive endoderm.

The transcription factor GATA6 and the Fgf/Ras/MAPK signaling pathway are essential for the development of the primitive endoderm (PrE), one of the two lineages derived from the pluripotent inner cell mass (ICM) of mammalian blastocysts. A mutant mouse line in which Gata6-coding exons are replaced with H2BGFP (histone H2B Green Fluorescence Protein fusion protein) was developed to monitor Gata6 promoter activity. In the Gata6-H2BGFP heterozygous blastocysts, the ICM cells that initially had uniform GFP fluorescence signal at E3.5 diverged into two populations by the 64-cell stage, either as the GFP-high PrE or the GFP-low epiblasts (Epi). However in the GATA6-null blastocysts, the originally moderate GFP expression subsided in all ICM cells, indicating that the GATA6 protein is required to maintain its own promoter activity during PrE linage commitment. In embryonic stem cells, expressed GATA6 was shown to bind and activate the Gata6 promoter in PrE differentiation. Mutations of a conserved serine residue (S264) for Erk1/2 phosphorylation in GATA6 protein drastically impacted its ability to activate its own promoter. We conclude that phosphorylation of GATA6 by Erk1/2 compels exit from pluripotent state, and the phosphorylation propels a GATA6 positive feedback regulatory circuit to compel PrE differentiation. Our findings resolve the longstanding question on the dual requirements of GATA6 and Ras/MAPK pathway for PrE commitment of the pluripotent ICM.