Latin Dance Effects on Cardiorespiratory Fitness and Physical Function in Middle-Aged and Older Latino Adults

We tested if a dance trial yielded improvements in physical function and cardiorespiratory fitness (CRF) in middle-aged/older Latino adults. Physical activity was assessed using the Community Healthy Activities Model Program for Seniors, physical function with the Short Physical Performance Battery (SPPB) protocol, and estimated CRF with the Jurca nonexercise test model. Multivariate analysis of covariance models found significant change in SPPB protocol total scores, F(1, 329) = 4.23, p = .041, and CRF, F(1, 329) = 5.16, p = .024, between the two study arms in favor of the dance group. Mediation models found moderate- to vigorous-intensity physical activity to mediate to mediate between group and SPPB scores (β = 0.054, 95% confidence interval [0.0142, 0.1247]). Moderate- to vigorous-intensity physical activity and total physical activity were found to partially mediate between group and CRF (β = 0.02, 95% confidence interval [-0.0261, 0.0751]), with the direct pathway no longer being significant (p > .05). This provides support for Latin dance programs to have an effect on SPPB protocol and CRF.

Temporary Knockdown of p53 During Focal Limb Irradiation Increases the Development of Sarcomas

Approximately half of patients with cancer receive radiotherapy and, as cancer survivorship increases, the low rate of radiation-associated sarcomas is rising. Pharmacologic inhibition of p53 has been proposed as an approach to ameliorate acute injury of normal tissues from genotoxic therapies, but how this might impact the risk of therapy-induced cancer and normal tissue injuries remains unclear. We utilized mice that express a doxycycline (dox)-inducible p53 short hairpin RNA to reduce Trp53 expression temporarily during irradiation. Mice were placed on a dox diet 10 days prior to receiving 30 or 40 Gy hind limb irradiation in a single fraction and then returned to normal chow. Mice were examined weekly for sarcoma development and scored for radiation-induced normal tissue injuries. Radiation-induced sarcomas were subjected to RNA sequencing. Following single high-dose irradiation, 21% of animals with temporary p53 knockdown during irradiation developed a sarcoma in the radiation field compared with 2% of control animals. Following high-dose irradiation, p53 knockdown preserves muscle stem cells, and increases sarcoma development. Mice with severe acute radiation-induced injuries exhibit an increased risk of developing late persistent wounds, which were associated with sarcomagenesis. RNA sequencing revealed radiation-induced sarcomas upregulate genes related to translation, epithelial-mesenchymal transition (EMT), inflammation, and the cell cycle. Comparison of the transcriptomes of human and mouse sarcomas that arose in irradiated tissues revealed regulation of common gene programs, including elevated EMT pathway gene expression. These results suggest that blocking p53 during radiotherapy could minimize acute toxicity while exacerbating late effects including second cancers.

SIGNIFICANCE

Strategies to prevent or mitigate acute radiation toxicities include pharmacologic inhibition of p53 and other cell death pathways. Our data show that temporarily reducing p53 during irradiation increases late effects including sarcomagenesis.

Abstract 6130: Cancer sensitivity to therapy is constrained by apoptosis regulation in cells of origin

Many chemotherapeutic agents target cellular components or processes that are present in all cancers, yet clinical responses to these agents vary greatly between cancer types and even patient age - the basis for these broad-scale differences are unclear. The vast majority of targeted and cytotoxic cancer therapies including ionizing radiation produce pro-apoptotic signaling in exposed cells, suggesting that the mitochondrial apoptosis sensitivity of cancer cells could act as a central signaling “node” to broadly impact therapy outcomes. To test this, we used BH3 profiling and complementary chemosensitivity assays to analyze hundreds of primary cancer specimens across twelve major cancer types. We find that cancers with typically favorable outcomes including certain hematologic malignancies, testicular cancer, and some pediatric cancers contain mitochondria that are highly primed for apoptosis, which renders them hypersensitive to cytotoxic as well as targeted agents and radiation therapy. Priming levels in many epithelial cancers including ovarian cancer and non-small cell lung cancer are highly heterogeneous, mirroring their variability in clinical outcomes. Finally, many tumor types that are typically chemoresistant including adult soft tissue sarcomas, hepatocellular carcinoma and pancreatic cancer are almost completely resistant to pro-apoptotic signaling. By analyzing in vitro and in vivo pancreatic, ovarian, hepatocellular and sarcoma tumorigenesis models, we find that apoptotic priming generally increases during neoplastic transformation, in part due to consistent upregulation of pro-apoptotic proteins BAX and BAK. However, the level of apoptotic priming in cancer cells is constrained by the baseline apoptosis sensitivity of normal cells prior to transformation. Remarkably, we find that apoptotic priming is dynamically regulated by cell lineage and differentiation state but can also be modulated by oncogenes. For instance, Myc activation typically increases apoptotic priming while activation of mutant Ras signaling decreases it - these changes in priming alter the chemosensitivity of cancer cells. Finally, we use inducible mouse tumor models to demonstrate that neoplastic transformation of cells from developmentally immature tissues yields pediatric tumors that are more primed for apoptosis than equivalent tumors arising in adults. This difference in priming causes pediatric tumors to be more sensitive to front-line therapies and BH3 mimetics targeting pro-survival BCL-2 family proteins in vitro and in vivo. Thus, lineage-determined regulation of apoptosis prior to and during neoplastic transformation leads to broad-scale differences in cancer cell chemosensitivity and can be exploited therapeutically by targeting BCL-2 family proteins.

Citation Format: Cameron Fraser, Xingping Qin, Kenichi Shimada, Johan Spetz, Mary Heather Florido, Rumani Singh, Stacey Yu, Adam Presser, Zintis Inde, Gaurav Joshi, Jennifer Guerriero, Francisco Sanchez-Rivera, Alison Karst, Omar Lopez, Chendi Li, Peter Winter, Ying Yue, Peter Sorger, Jingwei Cheng, Izidore Lossos, Aaron Hata, Ronny Drapkin, Adam Palmer, James Decaprio, Manisha Thakuria, Charles Yoon, Ursula Matulonis, Matthew Meyerson, Elizabeth Stover, Diana Cardona, Kris Wood, Shayna Sarosiek, David Kirsch, Joseph Mancias, Andrew Cherniack, Anthony Letai, Kristopher Sarosiek. Cancer sensitivity to therapy is constrained by apoptosis regulation in cells of origin. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6130.

Comparing ultrastable lasers at 7 × 10-17 fractional frequency instability through a 2220 km optical fibre network

Ultrastable lasers are essential tools in optical frequency metrology enabling unprecedented measurement precision that impacts on fields such as atomic timekeeping, tests of fundamental physics, and geodesy. To characterise an ultrastable laser it needs to be compared with a laser of similar performance, but a suitable system may not be available locally. Here, we report a comparison of two geographically separated lasers, over the longest ever reported metrological optical fibre link network, measuring 2220 km in length, at a state-of-the-art fractional-frequency instability of 7 × 10-17 for averaging times between 30 s and 200 s. The measurements also allow the short-term instability of the complete optical fibre link network to be directly observed without using a loop-back fibre. Based on the characterisation of the noise in the lasers and optical fibre link network over different timescales, we investigate the potential for disseminating ultrastable light to improve the performance of remote optical clocks.

Feasibility of Nurse-Led Multidimensional Outcome Assessments in the Neuroscience Intensive Care Unit

BACKGROUND

The outcome focus for survivors of critical care has shifted from mortality to patient-centered outcomes. Multidimensional outcome assessments performed in critically ill patients typically exclude those with primary neurological injuries.

OBJECTIVE

To determine the feasibility of measurements of physical function, cognition, and quality of life in patients requiring neurocritical care.

METHODS

This evaluation of a quality improvement initiative involved all patients admitted to the neuroscience intensive care unit at the University of Cincinnati Medical Center.

INTERVENTIONS

Telephone assessments of physical function (Glasgow Outcome Scale-Extended and modified Rankin Scale scores), cognition (modified Telephone Interview for Cognitive Status), and quality of life (5-level EQ-5D) were conducted between 3 and 6 months after admission.

RESULTS

During the 2-week pilot phase, the authors contacted and completed data entry for all patients admitted to the neuroscience intensive care unit over a 2-week period in approximately 11 hours. During the 18-month implementation phase, the authors followed 1324 patients at a mean (SD) time of 4.4 (0.8) months after admission. Mortality at follow-up was 38.9%; 74.8% of these patients underwent withdrawal of care. The overall loss to follow-up rate was 23.6%. Among all patients contacted, 94% were available by the second attempt to interview them by telephone.

CONCLUSIONS

Obtaining multidimensional outcome assessments by telephone across a diverse population of neurocritically ill patients was feasible and efficient. The sample was similar to those in other cohort studies in the neurocritical care population, and the loss to follow-up rate was comparable with that of the general critical care population.

Abstract 1961: Preclinical development of NSC-801845, a new cytidine analog, in comparative cell culture and xenograft studies with the clinical candidates T-dCyd and aza-T-dCyd

Cytidine analogs remain an area of active drug discovery and development with four FDA approved drugs. DNMT1, a maintenance methyltransferase that contributes to the hypermethylation and silencing of tumor suppressor genes, is a major molecular target of these agents. In addition, DNMT1 has roles independent of its methyltransferase activity and DNMT1 knockout results in decreased cell viability preceded by events consistent with activation of DNA damage response. 4'-thio-2'-deoxycytidine (T-dCyd) and 5-aza-4'-thio-2'-deoxycytidine (aza-T-dCyd) are two cytidine analogs that deplete DNMT1 both in vitro and in vivo in tumor cells. T-dCyd and aza-T-dCyd are currently in Phase I clinical trial at The National Cancer Institute (T-dCyd (NCT02423057) and aza-T-dCyd (NCT03366116)). Herein NSC-801845, a new cytidine analog, is compared with T-dCyd and aza-T-dCyd in cell culture and mouse xenograft studies in HCT-116 human colon carcinoma, BL0382 human bladder carcinoma, OVCAR3 human ovarian carcinoma, NCI-H23 human NSCLC carcinoma, and HL-60 human leukemia. In a 7-day monolayer culture cytotoxicity experiment, NSC-801845 was more potent than T-dCyd and less potent than aza-T-dCyd. In the 5 cell lines listed, the IC50s for NSC-801845 ranged from 3.7 uM to 0.2 uM in the 7-day experiment. In xenograft studies, T-dCyd was the least effective of the three cytidine analogs. In three of five xenograft lines (HCT-116, HL-60 and BL-0382), NSC-801845 was more efficacious than aza-T-dCyd (administered at the MTD of 1.5 mg/kg, IP). Comparable activity was observed for these two agents against the NCI-H23 and OVCAR3 xenografts. In the HCT-116 study, NSC-801845 (dosed 10 mg/kg IP, QDx5 for 4 cycles), produced complete regression of the tumors in all mice with a response that proved durable out to 150 days. Similarly, complete tumor regression was observed in the HL-60 leukemia xenograft when mice were dosed with NSC-801845 (10 mg/kg IP, QDx5 for 3 cycles). In the BL-0382 bladder study, oral and IP dosing of NSC-801845 (8 mg/kg PO, QDx5 for 3 cycles; 8 mg/kg IP QDx5, QDx5 for 3 cycles) produced regressions that showed tumor regrowth 13-days post dosing. This project was funded in part with federal funds from the NCI, NIH, under contract no. HHSN261200800001E. NCI-Frederick is accredited by AAALACi and follows the Public Health Service Policy on the Care and Use of Laboratory Animals. These studies were conducted on an approved Institutional Animal Care and Use Committee approved protocol.

Citation Format: Joel Morris, Donn Wishka, Omar Lopez, Beverly A. Teicher, Raymond Divelbiss, Suzanne Borgel, Kyle Georgius, John Carter, Howard Stotler, Jerry Collins, Melinda Hollingshead. Preclinical development of NSC-801845, a new cytidine analog, in comparative cell culture and xenograft studies with the clinical candidates T-dCyd and aza-T-dCyd [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1961.

The Experience of a Neurocritical Care Admission and Discharge for Patients and Their Families: A Qualitative Analysis

INTRODUCTION

A qualitative assessment of discharge resource needs is important for developing evidence-based care improvements in neurocritically ill patients.

METHODS

We conducted a quality improvement initiative at an academic hospital and included all patients admitted to the neuroscience intensive care unit (ICU) during an 18-month period. Telephone assessments were made at 3 to 6 months after admission. Patients or caregivers were asked whether they had adequate resources upon discharge and whether they had any unanswered questions. The content of responses was reviewed by a neurointensivist and a neurocritical care nurse practitioner. A structured codebook was developed, organized into themes, and applied to the responses.

RESULTS

Sixty-one patients or caregivers responded regarding access to resources at discharge with 114 individual codable responses. Responses centered around 5 themes with 23 unique codes: satisfied, needs improvement, dissatisfied, poor post-ICU care, and poor health. The most frequently coded responses were that caregivers believed their loved one had experienced an unclear discharge (n = 11) or premature discharge (n = 12). Two hundred four patients or caregivers responded regarding unanswered questions or additional comments at follow-up, with 516 codable responses. These centered around 6 themes with 26 unique codes: positive experience, negative experience, neutral experience, medical questions, ongoing medical care or concern, or remembrance of time spent in the ICU. The most frequent response was that caregivers or patients stated that they received good care (n = 115). Multiple concerns were brought up, including lack of follow-up after hospitalization (n = 15) and dissatisfaction with post-ICU care (n = 15).

CONCLUSIONS

Obtaining qualitative responses after discharge provided insight into the transition from critical care. This could form the basis for an intervention to provide a smoother transition from the ICU to the outpatient setting.

The Long Noncoding RNA NEAT1 Promotes Sarcoma Metastasis by Regulating RNA Splicing Pathways

Soft-tissue sarcomas (STS) are rare malignancies showing lineage differentiation toward diverse mesenchymal tissues. Half of all high-grade STSs develop lung metastasis with a median survival of 15 months. Here, we used a genetically engineered mouse model that mimics undifferentiated pleomorphic sarcoma (UPS) to study the molecular mechanisms driving metastasis. High-grade sarcomas were generated with Cre recombinase technology using mice with conditional mutations in Kras and Trp53 (KP) genes. After amputation of the limb bearing the primary tumor, mice were followed for the development of lung metastasis. Using RNA-sequencing of matched primary KP tumors and lung metastases, we found that the long noncoding RNA (lncRNA) Nuclear Enriched Abundant Transcript 1 (Neat1) is significantly upregulated in lung metastases. Furthermore, NEAT1 RNA ISH of human UPS showed that NEAT1 is upregulated within a subset of lung metastases compared with paired primary UPS. Remarkably, CRISPR/Cas9-mediated knockout of Neat1 suppressed the ability of KP tumor cells to colonize the lungs. To gain insight into the underlying mechanisms by which the lncRNA Neat1 promotes sarcoma metastasis, we pulled down Neat1 RNA and used mass spectrometry to identify interacting proteins. Interestingly, most Neat1 interacting proteins are involved in RNA splicing regulation. In particular, KH-Type Splicing Regulatory Protein (KHSRP) interacts with Neat1 and is associated with poor prognosis of human STS. Moreover, depletion of KHSRP suppressed the ability of KP tumor cells to colonize the lungs. Collectively, these results suggest that Neat1 and its interacting proteins, which regulate RNA splicing, are involved in mediating sarcoma metastasis. IMPLICATIONS: Understanding that lncRNA NEAT1 promotes sarcoma metastasis, at least in part, through interacting with the RNA splicing regulator KHSRP may translate into new therapeutic approaches for sarcoma.

Targeted chemotherapy overcomes drug resistance in melanoma

In this study, Yue et al. describe a therapeutic strategy termed “targeted chemotherapy” that involves depleting PP2A or inhibiting it using a small molecule inhibitor, phendione, in drug-resistant melanoma. The authors show phendione induces DNA damage response without causing DNA breaks or inducing cellular dormancy, therefore blocking tumor growth of BRAF mutant and NRAS mutant melanomas.

The emergence of drug resistance is a major obstacle for the success of targeted therapy in melanoma. Additionally, conventional chemotherapy has not been effective as drug-resistant cells escape lethal DNA damage effects by inducing growth arrest commonly referred to as cellular dormancy. We present a therapeutic strategy termed “targeted chemotherapy” by depleting protein phosphatase 2A (PP2A) or its inhibition using a small molecule inhibitor (1,10-phenanthroline-5,6-dione [phendione]) in drug-resistant melanoma. Targeted chemotherapy induces the DNA damage response without causing DNA breaks or allowing cellular dormancy. Phendione treatment reduces tumor growth of BRAF^V600E-driven melanoma patient-derived xenografts (PDX) and diminishes growth of NRAS^Q61R-driven melanoma, a cancer with no effective therapy. Remarkably, phendione treatment inhibits the acquisition of resistance to BRAF inhibition in BRAF^V600E PDX highlighting its effectiveness in combating the advent of drug resistance.

An improved algorithm of white matter hyperintensity detection in elderly adults

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OASIS-AD is a method for automatic segmentation of white matter hyperintensities in older adults using structural brain MRIs.

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OASIS-AD is an approach evolved from OASIS, which was developed for automatic lesion segmentation in multiple sclerosis.

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OASIS-AD is a major refinement of OASIS that takes into account the specific challenges raised by white matter hyperintensities in Alzheimer’s disease.

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OASIS-AD combines three processing steps: 1) using an eroding procedure on the skull stripped mask; 2) adding a nearest neighbor feature construction approach; and 3) applying a Gaussian filter to refine segmentation results creating a novel process for WMH detection in aging population .

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OASIS-AD performs better than existing automatic white matter hyperintensity segmentation approaches.

Automated segmentation of the aging brain raises significant challenges because of the prevalence, extent, and heterogeneity of white matter hyperintensities. White matter hyperintensities can be frequently identified in magnetic resonance imaging (MRI) scans of older individuals and among those who have Alzheimer’s disease. We propose OASIS-AD, a method for automatic segmentation of white matter hyperintensities in older adults using structural brain MRIs. OASIS-AD is an approach evolved from OASIS, which was developed for automatic lesion segmentation in multiple sclerosis. OASIS-AD is a major refinement of OASIS that takes into account the specific challenges raised by white matter hyperintensities in Alzheimer’s disease. In particular, OASIS-AD combines three processing steps: 1) using an eroding procedure on the skull stripped mask; 2) adding a nearest neighbor feature construction approach; and 3) applying a Gaussian filter to refine segmentation results, creating a novel process for WMH detection in aging population. We show that OASIS-AD performs better than existing automatic white matter hyperintensity segmentation approaches.

First industrial-grade coherent fiber link for optical frequency standard dissemination

We report on a fully bidirectional 680 km fiber link connecting two cities for which the equipment, the setup, and the characterization are managed for the first time by an industrial consortium. The link uses an active telecommunication fiber network with parallel data traffic and is equipped with three repeater laser stations and four remote double bidirectional erbium-doped fiber amplifiers. We report a short-term stability at 1 s integration time of 5.4×10^-16 in 0.5 Hz bandwidth and a long-term stability of 1.7×10^-20 at 65,000 s of integration time. The accuracy of the frequency transfer is evaluated as 3×10^-20. No shift is observed within the statistical uncertainty. We show a continuous operation over five days with an uptime of 99.93%. This performance is comparable with the state-of-the-art coherent links established by National Metrology Institutes in Europe. It is a first step in the construction of an optical fiber network for metrology in France, which will give access to an ultrahigh performance frequency standard to a wide community of scientific users.

Ecosystem state shifts during long-term development of an Amazonian peatland

The most carbon (C)-dense ecosystems of Amazonia are areas characterized by the presence of peatlands. However, Amazonian peatland ecosystems are poorly understood and are threatened by human activities. Here, we present an investigation into long-term ecohydrological controls on C accumulation in an Amazonian peat dome. This site is the oldest peatland yet discovered in Amazonia (peat initiation ca. 8.9 ka BP), and developed in three stages: (i) peat initiated in an abandoned river channel with open water and aquatic plants; (ii) inundated forest swamp; and (iii) raised peat dome (since ca. 3.9 ka BP). Local burning occurred at least three times in the past 4,500 years. Two phases of particularly rapid C accumulation (ca. 6.6-6.1 and ca. 4.9-3.9 ka BP), potentially resulting from increased net primary productivity, were seemingly driven by drier conditions associated with widespread drought events. The association of drought phases with major ecosystem state shifts (open water wetland-forest swamp-peat dome) suggests a potential climatic control on the developmental trajectory of this tropical peatland. A third drought phase centred on ca. 1.8-1.1 ka BP led to markedly reduced C accumulation and potentially a hiatus during the peat dome stage. Our results suggest that future droughts may lead to phases of rapid C accumulation in some inundated tropical peat swamps, although this can lead ultimately to a shift to ombrotrophy and a subsequent return to slower C accumulation. Conversely, in ombrotrophic peat domes, droughts may lead to reduced C accumulation or even net loss of peat. Increased surface wetness at our site in recent decades may reflect a shift towards a wetter climate in western Amazonia. Amazonian peatlands represent important carbon stores and habitats, and are important archives of past climatic and ecological information. They should form key foci for conservation efforts.

A clock network for geodesy and fundamental science

Leveraging the unrivalled performance of optical clocks as key tools for geo-science, for astronomy and for fundamental physics beyond the standard model requires comparing the frequency of distant optical clocks faithfully. Here, we report on the comparison and agreement of two strontium optical clocks at an uncertainty of 5 × 10⁻¹⁷ via a newly established phase-coherent frequency link connecting Paris and Braunschweig using 1,415 km of telecom fibre. The remote comparison is limited only by the instability and uncertainty of the strontium lattice clocks themselves, with negligible contributions from the optical frequency transfer. A fractional precision of 3 × 10⁻¹⁷ is reached after only 1,000 s averaging time, which is already 10 times better and more than four orders of magnitude faster than any previous long-distance clock comparison. The capability of performing high resolution international clock comparisons paves the way for a redefinition of the unit of time and an all-optical dissemination of the SI-second.

Comparing the frequency of two distant optical clocks will enable sensitive tests of fundamental physics. Here, the authors compare two strontium optical-lattice clocks 690 kilometres apart to a degree of accuracy that is limited only by the uncertainty of the individual clocks themselves.

Abstract 3456: Macrophages as independent prognostic factors in small T1 breast cancers

Breast cancer is the second leading cause of death by cancer in women in the United States. The occurrence of high numbers of macrophages in the tumor stroma has been associated with tumor progression and poor prognosis in breast and other solid malignances. However, macrophage numbers in tumors have not been validated as a prognostic factor in clinical practice. The present analysis was designed as a pilot study aimed at determining whether the presence of CD68+ macrophages is an independent prognostic factor in small T1 ER+ breast cancers across three different ethnic groups, i.e. African American, Latinas and Caucasian women. A retrospective pilot analysis of 30 T1 breast cancers cases encompassing these three ethnic groups was carried out. African

American and Latina women present with less incidence but more aggressive breast cancer disease and therefore proportionally higher death rates. Using immunohistochemistry, we sought to find out whether there was any association between the presence and density of CD68+ macrophages and standard prognostic markers with overall survival in these groups. Our data showed that overall survival did not differ significantly for the occurrence or density of CD68+ macrophages in T1 ER+ tumors. There were also no significant differences in overall survival for the occurrence of CD68+ macrophages across ethnicities, although macrophage numbers were significantly higher in tumors from African American and Latinas than in Caucasian patients. Interestingly but not surprisingly, the absence of PR associated very strongly with decreased overall survival. This pilot project shows that CD68+ macrophages are not pivotal in determining tumor prognosis in early T1 breast cancers. New studies are presently being conducted to assess the value of different macrophage markers and macrophage activation profiles as prognostic factors in breast cancers of different clinical stages, using a larger number of patients among these three different ethnicities.

Citation Format: Roberto Carrio, Tulay Koru-Sengul, Feng Miao, Stefan Gluck, Omar Lopez, Yamil Selman, Consuelo Alvarez, Clara Milikowski, Carmen Gomez, Merce Jorda, Mehrad Nadji, Marta Torroella-Kouri. Macrophages as independent prognostic factors in small T1 breast cancers. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3456. doi:10.1158/1538-7445.AM2013-3456

Macrophages as independent prognostic factors in small T1 breast cancers

Breast cancer is the second leading cause of death by cancer in women in the United States. The occurrence of high numbers of macrophages in the tumor stroma has been associated with tumor progression and poor prognosis in breast and other solid malignancies. However, macrophage numbers in tumors have not been validated as a prognostic factor in clinical practice. The present analysis was designed as a pilot study aimed at determining whether the presence of CD68+ macrophages is an independent prognostic factor in small T1 estrogen receptor (ER)+ breast cancers across three different ethnic groups, i.e. African-American, Latina and Caucasian women. A retrospective pilot analysis of 30 T1 breast cancer cases encompassing these three ethnic groups was carried out. African-American and Latina women present with less incidence but more aggressive breast cancer disease and, therefore, proportionally higher death rates. Using immuno-histochemistry, we sought to identify whether there was any association between the presence and density of CD68+ macrophages and standard prognostic markers with overall survival in these groups. Our data revealed that overall survival did not differ significantly for the occurrence or density of CD68+ macrophages in T1 ER+ tumors. There were also no significant differences in overall survival for the occurrence of CD68+ macrophages across ethnicities, although macrophage numbers were significantly higher in tumors from African-American and Latina than in Caucasian patients. Importantly, but not surprisingly, the absence of the progesterone receptor was associated very strongly with decreased overall survival. This pilot project shows that CD68+ macrophages are not pivotal in determining tumor prognosis in early T1 breast cancers. New studies are presently being conducted to assess the value of different macrophage markers and macrophage activation profiles as prognostic factors in breast cancers of different clinical stages, using a larger number of patients among these three different ethnicities.

Study of nuclear stopping in central collisions at intermediate energies

Nuclear stopping has been investigated in central nuclear collisions at intermediate energies by analyzing kinematically complete events recorded with the help of the 4π multidetector INDRA for a large variety of symmetric systems. It is found that the mean isotropy ratio defined as the ratio of transverse to parallel momenta (energies) reaches a minimum near the Fermi energy, saturates or slowly increases depending on the mass of the system as the beam energy increases, and then stays lower than unity, showing that significant stopping is not achieved even for the heavier systems. Close to and above the Fermi energy, experimental data show no effect of the isospin content of the interacting system. A comparison with transport model calculations reveals that the latter overestimates the stopping power at low energies.

Phase diagram of the charged lattice-gas model with two types of particles

A lattice-gas model with two types of particles, a particle-dependent short-range coupling and a long-range repulsive Coulombic interaction, is introduced. The phase diagram of an isolated finite system of 129 particles is constructed using the bimodality properties of the observables' distribution. We show that this generic Hamiltonian, with couplings optimized on the properties of the atomic nucleus, exhibits a specific phase diagram including, together with the well-known liquid-gas phase transition, a segregation phase that can be assimilated to nuclear fission.

Isoscaling as a measure of symmetry energy in the lattice gas model

The energetic properties of nuclear clusters inside a low-density, finite-temperature medium are studied with a lattice gas model including isospin dependence and Coulomb forces. Important deviations are observed with respect to the Fisher approximation of an ideal gas of noninteracting clusters, but a simple modified energy-density functional can still describe the global energetics. The multifragmentation regime is dominated by combinatorial effects, but the isoscaling of the largest fragment appears to be a promising observable for the experimental measurement of the symmetry energy.

Cutaneous leishmaniasis due to Leishmania chagasi/Le. infantum in an endemic area of Guarico State, Venezuela

This study reports cutaneous leishmaniasis (CL) caused by Leishmania chagasi/Le. infantum in Venezuela, with some atypical characteristics. Out of 63 cases of CL in the suburbs of Altagracia de Orituco, Guarico State, Venezuela, 30 presented clinical, parasitological, immunological and epidemiological features different from those of the classical CL known in the country. The initial lesion was small and nodular, which, if not treated, might progress to a superficial ulcer. No secondary infection was observed. The identification of the isolates was carried out by molecular techniques. Twelve species of phlebotomine sandflies were caught, the most abundant being Lutzomyia evansi and Lu. longipalpis s.l., known vectors of Le. chagasi/Le. infantum. The existence of Le. chagasi/Le. infantum and its vectors in an endemic area of CL has implications and we suggest that epidemiological studies should be carried out to obtain a clearer picture of the extent of this CL form in Venezuela.