Plant-soil feedbacks of forest understorey plants transplanted in nonlocal soils along a latitudinal gradient

Climate change is driving movements of many plants beyond, as well as within, their current distributional ranges. Even migrant plants moving within their current range may experience different plant-soil feedbacks (PSF) because of divergent nonlocal biotic soil conditions. Yet, our understanding to what extent soil biotic conditions can affect the performance of within-range migrant plants is still very limited. We assessed the emergence and growth of migrant forest herbs (Milium effusum and Stachys sylvatica) using soils and seeds collected along a 1,700 km latitudinal gradient across Europe. Soil biota were manipulated through four soil treatments, i.e. unsterilized control soil (PSF_US ), sterilized soil (PSF_S ), sterilized soil inoculated with unsterilized home soil (PSF_S+HI ) and sterilized soil inoculated with unsterilized foreign soil (PSF_S+FI , expected to occur when both plants and soil biota track climate change). Compared to PSF_S , PSF_US had negative effects on the growth but not emergence of both species, while PSF_S+FI only affected S. sylvatica across all seed provenances. When considering seed origin, seedling emergence and growth responses to nonlocal soils depended on soil biotic conditions. Specifically, the home-away distance effect on seedling emergence differed between the four treatments, and significant responses to chemistry either disappeared (M. effusum) or changed (S. sylvatica) from PSF_US to PSF_S . Soil biota emerge as an important driver of the estimated plant migration success. Our results of the effects of soil microorganisms on plant establishment provide relevant information for predictions of the distribution and dynamics of plant species in a changing climate.

[An incident of toadstool poisoning]

Objective: To investigate a poisonous mushroom poisoning incident and analyze its clinical data. Methods: Investigate a poisonous mushroom poisoning incident in a place in Shandong in July 2018, at the same time, the clinical data of 2 cases of mushroom poisoning were analyzed and summarized. Results: The incident was caused by a poisoning incident caused by residents eating poisonous mushrooms. The poisonous mushroom in this incident was identified as a scaled white goose cream. Two patients with poisoning developed gastrointestinal symptoms such as nausea and vomiting, abdominal pain and diarrhea, and liver damage occurred later. After active rescue and treatment, one patient was discharged from hospital, and the other patient developed acute pulmonary embolism during the treatment. He was discharged after interventional thrombolysis and follow-up treatment. Conclusion: After investigation, the incident was caused by the ingestion of poisonous mushrooms mainly based on the scalloped white goose cream. After active treatment, they were cured and discharged.

Expression of Mucin 1 in salivary gland tumors and its correlation with clinicopathological factors

This study aimed to detect the expression of Mucin 1 (MUC1) in acinic cell carcinoma (AciCC) of salivary gland and to explore the relationship between MUC1 and clinicopathological factors of AciCC of salivary gland. Patients with salivary gland tumors who were treated at our hospital were enrolled in this study. The pathological sections collected from all subjects were classified by histological examinations. In addition, 40 cases of primary salivary gland AciCC tissues were selected and classified into experimental group, whereas 40 cases of normal salivary gland (NSG) tissues were selected and classified into control group. MUC1 positive cells in both experimental and control groups were detected by immunohistochemistry assays, while all clinical data were analyzed statistically. The results showed that MUC1 was only expressed in the ductal epithelium of NSG and distributed at the apical side of the cell membrane. In primary salivary gland AciCC tissues, scattered expressions of MUC1 were found both on the cell membrane and in the cytoplasm of tumor cells, and sometimes even in the cell nuclei, thus completely eliminating the polarized distribution of MUC1 expressions. The percentage of MUC1 positive cells in experimental group was significantly higher than that in control group (P < 0.05). In addition, the expression of MUC1 in salivary gland AciCC was correlated with gender, age, histological type, lesion location, cervical lymph node metastasis, local recurrence, and distant metastasis. In conclusion, MUC1 is related to the occurrence and development of salivary gland AciCC. Therefore, MUC1 may be used as a novel tumor marker in the clinical diagnosis and treatment of salivary gland AciCC.

The Long-Term Impact of Functional Disability on Hospitalization Spending in Singapore

Singapore is one of the fastest-aging populations due to increased life expectancy and lowered fertility. Lifestyle changes increase the burden of chronic diseases and disability. These have important implications for social protection systems. The goal of this paper is to model future functional disability and healthcare expenditures based on current trends. To project the health, disability and hospitalization spending of future elders, we adapted the Future Elderly Model (FEM) to Singapore. The FEM is a dynamic Markov microsimulation model developed in the US. Our main source of population data was the Singapore Chinese Health Study (SCHS) consisting of 63,000 respondents followed up over three waves from 1993 to 2010. The FEM model enables us to investigate the effects of disability compounded over the lifecycle and hospitalization spending, while adjusting for competing risk of multi-comorbidities. Results indicate that by 2050, 1 in 6 elders in Singapore will have at least one ADL disability and 1 in 3 elders will have at least one IADL disability, an increase from 1 in 12 elders and 1 in 5 elders respectively in 2014. The highest prevalence of functional disability will be in those aged 85 years and above. Lifetime hospitalization spending of elders aged 55 and above is US$24,400 (30.2%) higher among people with functional disability compared to those without disability. Policies that successfully tackle diabetes and promote healthy living may reduce or delay the onset of disability, leading to potential saving. In addition, further technological improvements may reduce the financial burden of disability.

Abstract P2-06-02: Development of a first-in-class small molecule inhibitor (EC359) targeting oncogenic LIF/LIFR signaling for the treatment of triple negative breast cancer

Background: Leukemia inhibitory factor (LIF) and its receptor LIFR are over-expressed in multiple solid tumors and play a key role in tumor growth, progression, and resistance to standard anti-cancer treatments. Triple-negative breast cancer (TNBC) lacks targeted therapies and represents a disproportional share of breast cancer (BCa) mortality. TNBC exhibits autocrine stimulation of the LIF/LIFR axis and overexpression of LIF is associated with poorer relapse-free survival in BCa patients. LIF signaling also promotes maintenance of stem cells. Therefore, targeting the LIF/LIFR axis may have therapeutic utility in TNBC.

Methods: We rationally designed a small organic molecule (EC359) that emulates the LIF/LIFR binding site and functions as a LIFR inhibitor from a library of compounds. In silico docking studies were used to identify the putative interaction of the EC359 and LIF/LIFR complex. Direct binding of EC359 to LIFR was confirmed using surface plasmon resonance (SPR) and microscale thermophoresis technique (MST) assays. In vitro activity was tested using Cell-Titer Glo, MTT, invasion, and apoptosis assays. Mechanistic studies were conducted using Western blot, reporter gene assays, and RNA-seq analysis. Xenograft, patient-derived xenograft (PDX), and patient-derived explant (PDEX) models were used for preclinical evaluation and toxicity.

Results: Molecular docking studies showed that EC359 interacts at the LIF/LIFR binding interface. SPR and MST studies confirmed direct interaction of EC359 to LIFR. EC359 reduced the growth of TNBC cells with high potency (IC50 50-100nM) and promoted apoptosis. Further, EC359 treatment reduced invasion and stemness of TNBC cells. EC359 activity is dependent on the expression levels of LIFR and showed little or no activity on TNBC cells that have low levels of LIFR or ER+ve BCa cells. Further, EC359 significantly reduced the viability of cisplatin and taxane-resistant TNBC cells and enhanced the efficacy of HDAC inhibitors. Mechanistic and biochemical studies showed that EC359 interacts with LIFR and effectively blocking LIF/LIFR interactions. EC359 also blocked LIFR interactions with other LIFR ligands such as oncostatin M, ciliary neurotrophic factor, and cardiotrophin-1. EC359 treatment attenuated the activation of LIF/LIFR driven pathways including STAT3, mTOR, AKT, and MAPK. RNA-seq analysis identified regulation of apoptosis as one of the important pathway modulated by EC359. In TNBC xenograft and PDX assays, EC359 significantly reduced tumor progression. Further, using human primary BCa PDEX cultures, we demonstrated that EC359 has the potential to substantially reduce the proliferation of human BCa. Pharmacologically, EC359 exhibited high oral bioavailability and long half-life with a wide therapeutic window.

Conclusions: EC359 is a novel targeted therapeutic agent that inhibits LIF/LIFR oncogenic signaling in TNBC via a unique mechanism of action. EC359 has the distinct pharmacologic advantages of oral bioavailability, in vivo stability, and is associated with minimal systemic side effects. (DOD BCRP grant #BC170312)

Citation Format: Viswanadhapalli S, Luo Y, Sareddy GR, Santhamma B, Zhou M, Li M, Pratap UP, Altwegg KA, Li X, Srinivasan U, Ma S, Chang A, Riveros AC, Zhang KY, Dileep KV, Pan X, Murali R, Bajda M, Raj G, Brenner A, Manthati V, Rao M, Tekmal RR, Nair HB, Nickisch KJ, Vadlamudi RK. Development of a first-in-class small molecule inhibitor (EC359) targeting oncogenic LIF/LIFR signaling for the treatment of triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-06-02.

Direct Electron Transfer of Enzymes Facilitated by Cytochromes

The direct electron transfer (DET) of enzymes has been utilized to develop biosensors and enzymatic biofuel cells on micro- and nanostructured electrodes. Whereas some enzymes exhibit direct electron transfer between their active-site cofactor and an electrode, other oxidoreductases depend on acquired cytochrome domains or cytochrome subunits as built-in redox mediators. The physiological function of these cytochromes is to transfer electrons between the active-site cofactor and a redox partner protein. The exchange of the natural electron acceptor/donor by an electrode has been demonstrated for several cytochrome carrying oxidoreductases. These multi-cofactor enzymes have been applied in third generation biosensors to detect glucose, lactate, and other analytes. This review investigates and classifies oxidoreductases with a cytochrome domain, enzyme complexes with a cytochrome subunit, and covers designed cytochrome fusion enzymes. The structurally and electrochemically best characterized proponents from each enzyme class carrying a cytochrome, that is, flavoenzymes, quinoenzymes, molybdenum-cofactor enzymes, iron-sulfur cluster enzymes, and multi-haem enzymes, are featured, and their biochemical, kinetic, and electrochemical properties are compared. The cytochromes molecular and functional properties as well as their contribution to the interdomain electron transfer (IET, between active-site and cytochrome) and DET (between cytochrome and electrode) with regard to the achieved current density is discussed. Protein design strategies for cytochrome-fused enzymes are reviewed and the limiting factors as well as strategies to overcome them are outlined.

Abstract P5-04-23: Enhancing the activity of a novel estrogen receptor coregulator binding modulator (ERX-11) against ER-positive therapy resistant breast cancer

Background:We had previously reported a novel small molecule, ERX-11, that directly interacts with ER and blocks the interaction between a subset of coregulators with both native and mutant forms of ER. ERX-11 effectively blocks ER oncogenic signaling and has potent anti-proliferative activity against therapy-sensitive and therapy-resistant human breast cancer cells. To enhance the clinical translation of ERX-11, we sought to pursue both lead optimization and evaluate combinations of ERX-11 with other approved agents in breast cancer.

Methods: We designed, synthesized and tested 500 derivatives of ERX-11 in multiple models of ER+ breast cancer. We also tested combinations of ERX-11 with multiple agents, including other ER targeting agents, chemotherapies and CDK4/6 inhibitors. We tested the effect of combination therapy using breast cancer cells with acquired resistance (Tamoxifen, Letrozole, Ribociclib resistant) and engineered models that express ER mutations. In vitro activity was tested using Cell titer glo, MTT, and apoptosis assays. Mechanistic studies were conducted using Western blot, reporter gene assays and RNA-seq analysis. Xenograft, patient derived xenograft (PDX), patient derived explant (PDE) and xenograft derived explant (XDE) models were used for preclinical evaluation and toxicity.

Result: Evaluation of 500 analogs of ERX-11 identified a number of leads with differential activity against ER+ and ER- breast cancer cells, identified several analogs including ERX-144, 208, 296, 315 with nanomolar potency against ER+ and therapy-resistant ER+ breast cancers. Validation of the mechanism of action of these analogs is ongoing. The combination of ERX-11 and palbociclib significantly blocked ER-mediated and ER-coregulators mediated oncogenic signaling and showed potent anti-proliferative activity against both endocrine therapy-sensitive and resistant breast cancer cells. In addition, ERX-11 inhibited ribociclib-resistant ER+ cell proliferation in a dose dependent manner. Mechanistic studies using IP-Mass spectrometry demonstrated that ERX-11 and palbociclib blocks the interaction between larger subset of coregulators with ER in therapy resistant breast cancer models. ERX-11 and palbociclib both exhibited potent anti-proliferative activity against therapy-sensitive and therapy-resistant ER+ve breast cancer cells, in xenograft models and in PDEs. Importantly, combination therapy of ERX-11 and palbociclib synergistically reduced the growth of tamoxifen and letrozole resistant xenograft tumors compared to either drug alone. Mass spec based DIA analyses and RNA-seq studies revealed that combinational treatment uniquely activated p53, unfolded response mediated apoptotic pathways, altered DNA damage response and suppressed E2F and Myc target genes. Biochemical studies confirmed combination therapy significantly altered E2F1, ER and DNA damage response pathways.

Conclusion: We have successfully pursued two avenues to improving ERX-11 for clinical translation. We have developed ERX-11 analogs with higher potency against ER+ breast cancer. We have shown that combinational treatment with ERX-11 and palbociclib may overcome endocrine therapy resistance and CDK4/6 inhibitor (ribociclib) resistance.

Citation Format: Viswanadhapalli S, Ma S, Lee T-K, Sareddy GR, Liu X, Ekoue D, Alluri A, Luo Y, Kassees K, Arteaga C, Alluri P, Weintraub SE, Tekmal RR, Ahn J-M, Raj GV, Vadlamudi RK. Enhancing the activity of a novel estrogen receptor coregulator binding modulator (ERX-11) against ER-positive therapy resistant breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-04-23.

Abstract P4-07-01: A small molecule inhibitor (ERX-41) induces endoplasmic reticulum stress in triple negative breast cancer

Background: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer and represents a disproportional share of the breast cancer mortality, primarily due to a lack of targeted therapies. There is a major unmet need for rationally designed novel therapies that can extend survival of patients with TNBC. TNBCs are characterized by a high basal level of endoplasmic reticulum stress, due to high protein turnover and need for proliferation. Recent studies revealed the role of several members of the Nuclear Receptor (NR) superfamily as molecular drivers in TNBC, including the androgen receptor (AR), glucocorticoid receptor (GR) and the orphan NR tailless (TLX).

Methods: Recently, using peptidomimetics, we have developed small molecules that specifically target and block interactions of multiple coregulators with oncogenic NRs. We performed a screen of our 500+ compound peptidomimetic library derived from our ERX-11 oligobenzamide (that was rationally designed to target ERα) for anti-proliferative activity in TNBC cell lines. Identified leads were then validated in multiple TNBC cell lines. In vitro activity was tested using Cell titer glo, MTT, matrigel invasion, and apoptosis assays. Mechanistic studies were conducted using Western blot, reporter gene assays, CRISPR/Cas9 KO and RNA-seq analysis. Xenograft, patient derived xenograft (PDX), patient derived explant (PDE) and xenograft derived explant (XDE) TNBC models were used for preclinical evaluation and toxicity.

Results: We have identified a first-in-class drug (ERX-41) that has potent activity (IC50 = 50-250nM) against all six molecular subtypes of TNBC. Systematic evaluation using CRISPR/Cas9 KO screen and overexpression screen comprising 48 NRs identified TLX as a preferred target of ERX-41. Analyses of primary breast tumors revealed TLX was highly expressed in TNBC. Further, TLX was amplified in nearly 50% of TNBC xenografts (cbioportal.org). Modelling, mechanistic and biochemical studies showed that ERX-41 interact with TLX and selectively blocks its interactions with coregulators. Gene expression analyses revealed both significant reduction of TLX-activated genes (CCND1, WNT7A) and significant activation of TLX-repressed genes (p21) upon treatment with ERX-41 in TNBC models. Gene ontogeny pathway analyses of RNA-seq data in TNBC cells showed that ERX-41 treatment positively correlated with apoptosis. Our ultrastructural studies indicated that ERX-41 enhances endoplasmic reticulum stress in TNBC inducing autophagic flux and subsequent apoptosis. ERX-41 has significant potency against multiple TNBC xenografts and PDXs in vivo, PDEs and XDEs ex vivo, indicating its potential for clinical translation. Pharmacologically, ERX-41 exhibited high oral bioavailability and associated with minimal toxicity upon oral gavage for up to 120 days in animal studies.

Conclusions: We believe that the ability of ERX-41 to block NR signaling and target a critical molecular vulnerability in TNBC and its ability to enhance endoplasmic reticulum stress in TNBC, will revolutionize the therapeutic landscape of TNBC. ERX-41 is oral bioavailable, potent against multiple TNBC molecular subtypes, and is associated with minimal systemic side effects. (supported by NIH grant RO1 CA223828-01)

Citation Format: Liu X, Viswanadhapalli S, Ma S, Lee T-K, Sareddy GR, Ekoue DN, Blatt EM, Zhou M, Li M, Tekmal RR, Ahn J-m, Vadlamudi RK, Raj GV. A small molecule inhibitor (ERX-41) induces endoplasmic reticulum stress in triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-07-01.

Studying direct electron transfer by site-directed immobilization of cellobiose dehydrogenase

Covalent coupling between a surface exposed cysteine residue and maleimide groups was used to immobilize variants of Myriococcum thermophilum cellobiose dehydrogenase (MtCDH) at multiwall carbon nanotube electrodes. By introducing individual cysteine residues at particular places on the surface of the flavodehydrogenase domain of the flavocytochrome we are able to immobilize the different variants in different orientations. Our results show that direct electron transfer (DET) occurs exclusively through the haem b cofactor and that the redox potential of the haem is unaffected by the orientation of the enzyme. Electron transfer between the haem and the electrode is fast in all cases and at high glucose concentrations the catalytic currents are limited by the rate of inter-domain electron transfer (IET) between the FAD and the haem. Using ferrocene carboxylic acid as a mediator we find that the total amount of immobilized enzyme is 4 to 5 times greater than the amount of enzyme that participates in DET. The role of IET in the overall DET catalysed oxidation was also demonstrated by the effects of changing Ca2+ concentration and by proteolytic cleavage of the cytochrome domain on the DET and MET currents.

A facile synthesis of perforated reduced graphene oxide for high performance electrochemical sensors

Highly active perforated reduced graphene oxide (P-rGO) was synthesized by a facile methodology based on co-deposition of graphene oxide with sacrificial Prussian blue. Electrode surface properties were characterized by SEM and EDS. The GC/P-rGO electrode exhibited a larger specific surface area than that of GCE. These findings highlighted that the signal was enhanced for both dopamine detection and selenium detection by using P-rGO as a relevant supporting substrate. The result indicated that the large number of perforated structures formed numerous electrically conductive channels in the structure, improving the electrocatalytic properties.

Healthcare underutilization in middle-aged and elderly adults in China

OBJECTIVES

This article investigates the prevalence of, illness conditions associated with, and reasons for healthcare underutilization among middle-aged and elderly adults in China. It also identifies participants' characteristics associated with healthcare underutilization.

STUDY DESIGN

A cross-sectional survey was conducted in Beijing and Henan in August 2016.

METHODS

The survey was questionnaire-based. It focused on middle-aged and elderly persons aged 45 years and older. A total of 1778 people were surveyed.

RESULTS

In the end, 243 participants (30.11%) and 312 participants (32.13%) displayed signs of healthcare underutilization in Beijing and Henan, respectively. The disease conditions and reasons for underutilization were different in these two areas. Age group, marital status, education level, occupation, and chronic disease were found to be associated with healthcare underutilization in Beijing, whereas gender, age group, marital status, education level, and chronic disease were associated with healthcare underutilization in Henan.

CONCLUSIONS

Illness conditions, reasons for underutilization, and risk factors associated with healthcare underutilization were different in developed areas compared with developing areas of China. Further reforms and interventions are needed to consider these problems.

Antibiofilm efficacy of curcumin in combination with 2-aminobenzimidazole against single- and mixed-species biofilms of Candida albicans and Staphylococcus aureus

Mixed fungal and bacterial biofilm associated infections of implants have been a huge challenge in health care because of the increased resistance to antimicrobials and the critical biological differences between fungi and bacteria. In this study, we evaluated the 2-aminobenzimidazole (2ABI) and curcumin (CUR) alone to inhibit planktonic cell growth, adhesion as well as single and mixed species biofilms of Candida albicans and Staphylococcus aureus on silicone. The combined effects between 2ABI and CUR on mixed species biofilm formation and pre-formed biofilm were assessed. Our work showed that 2ABI or CUR alone was effective as a sole agent, inhibiting planktonic growth, adhesion and the biofilm formation of bacteria and fungi on the silicone surface. The combination of 2ABI and CUR exhibited the enhanced effect on mixed biofilm compared to mono-drug therapy. The biofilm architecture was investigated by scanning electron microscopy (SEM) and the distinction of living/dead organisms within biofilm was examined by confocal laser scanning microscopy (CLSM). The combination activity was most potent on mixed biofilm. These results suggest the potential applicability of 2ABI and CUR to treatment of biofilm related device infections.

Transcriptional control of K5, K6, K14, and K17 keratin genes by AP-1 and NF-kappaB family members

The expression of keratins K5 and K14 is restricted to the basal layers of the healthy epidermis, whereas the expression of K6 and K17 is induced in response to proliferative and inflammatory signals, respectively. The control of keratin expression occurs primarily at the transcriptional level. We studied the effects of transcription factors of the AP-1 and NF-kappaB families on the expression of those four keratin genes. We chose AP-1 and NF-kappaB proteins because they are activated by many extracellular signals, including those in hyperproliferative and inflammatory processes. DNA constructs expressing the transcription factors were, in various combinations, cotransfected with constructs containing keratin gene promoters and the CAT reporter gene into HeLa cells or keratinocytes. We found that the K5 and K14 promoters, which are coexpressed in vivo, are regulated in parallel by the cotransfected genes. Both were activated by the c-Fos and c-Jun components of AP-1, but not by Fra1. On the other hand, the NF-kappaB proteins, especially p65, suppressed these two promoters. The K17 promoter was specifically activated by c-Jun, whereas the other transcription factors tested had no significant effect. In contrast, the K6 promoter was very strongly activated by all AP-1 proteins, especially by the c-Fos + c-Jun and Fra1 + c-Jun combinations. It was also strongly activated by the p65 NF-kappaB protein. AP-1 and NF-kappaB acted synergistically in activating the K6 promoter, although the AP-1 and the NF-kappaB responsive sites could be separated physically. These results suggest that the interplay of AP-1 and NF-kappaB proteins regulates epidermal gene expression and that the activation of these transcription factors by extracellular signaling molecules brings about the differential expression of keratin genes in epidermal differentiation, cutaneous diseases, and wound healing.