Utilization of acid hydrolysate of recovered bacterial cell as a novel organic nitrogen source for L-tryptophan fermentation

In this study, waste bacterial cell (WBC) was recovered and used as an alternative to yeast extract in L-tryptophan fermentation. The effects of sulfuric acid concentration and temperature on the hydrolysis of WBC were optimized and the amino acid content in the waste bacterial cell hydrolysate (WBCH) was increased. Plackett-Burman and Box-Behnken design analysis revealed the optimum composition of the WBCH-based fermentation medium to be 22.47 g/L WBCH, 2.26 g/L KH₂PO₄, and 1.25 mg/L vitamin H. L-tryptophan yield and productivity with WBCH as the nitrogen source were 52.3 g/L and 2.16 g/L/h, respectively, which were 13% and 18% higher than those obtained with the yeast extract as the nitrogen source. In addition, WBCH did not affect the growth of Escherichia coli during L-tryptophan fermentation. Cost accounting showed that WBCH could be used as a novel and cheap organic nitrogen source for industrial L-tryptophan production.

Pseudomonas aeruginosa Polynucleotide Phosphorylase Contributes to Ciprofloxacin Resistance by Regulating PrtR

Pseudomonas aeruginosa is an opportunistic bacterial pathogen that causes various acute and chronic infections. It is intrinsically resistant to a variety of antibiotics. However, production of pyocins during SOS response sensitizes P. aeruginosa to quinolone antibiotics by inducing cell lysis. The polynucleotide phosphorylase (PNPase) is a conserved phosphate-dependent 3′–5′ exonuclease that plays an important role in bacterial response to environmental stresses and pathogenesis by influencing mRNA and small RNA stabilities. Previously, we demonstrated that PNPase controls the type III and type VI secretion systems in P. aeruginosa. In this study, we found that mutation of the PNPase coding gene (pnp) increases the bacterial resistance to ciprofloxacin. Gene expression analyses revealed that the expression of pyocin biosynthesis genes is decreased in the pnp mutant. PrtR, a negative regulator of pyocin biosynthesis genes, is upregulated in the pnp mutant. We further demonstrated that PNPase represses the expression of PrtR on the post-transcriptional level. A fragment containing 43 nucleotides of the 5′ untranslated region was found to be involved in the PNPase mediated regulation of PrtR. Overall, our results reveled a novel layer of regulation on the pyocin biosynthesis by the PNPase in P. aeruginosa.

Veratramine modulates AP-1-dependent gene transcription by directly binding to programmable DNA

Because the transcription factor activator protein-1 (AP-1) regulates a variety of protein-encoding genes, it is a participant in many cellular functions, including proliferation, transformation, epithelial mesenchymal transition (EMT), and apoptosis. Inhibitors targeting AP-1 have potential use in the treatment of cancer and other inflammatory diseases. Here, we identify veratramine as a potent natural modulator of AP-1, which selectively binds to a specific site (TRE 5′-TGACTCA-3′) of the AP-1 target DNA sequence and regulates AP-1-dependent gene transcription without interfering with cystosolic signaling cascades that might lead to AP-1 activation. Moreover, RNA-seq experiments demonstrate that veratramine does not act on the Hedgehog signaling pathway in contrast to its analogue, cyclopamine, and likely does not harbor the same teratogenicity and toxicity. Additionally, veratramine effectively suppresses EGF-induced AP-1 transactivation and transformation of JB6 P+ cells. Finally, we demonstrate that veratramine inhibits solar-ultraviolet-induced AP-1 activation in mice. The identification of veratramine and new findings in its specific regulation of AP-1 down stream genes pave ways to discovering and designing regulators to regulate transcription factor.

Metabolic Syndrome and Salt-Sensitive Hypertension in Polygenic Obese TALLYHO/JngJ Mice: Role of Na/K-ATPase Signaling

We have demonstrated that Na/K-ATPase acts as a receptor for reactive oxygen species (ROS), regulating renal Na⁺ handling and blood pressure. TALLYHO/JngJ (TH) mice are believed to mimic the state of obesity in humans with a polygenic background of type 2 diabetes. This present work is to investigate the role of Na/K-ATPase signaling in TH mice, focusing on susceptibility to hypertension due to chronic excess salt ingestion. Age-matched male TH and the control C57BL/6J (B6) mice were fed either normal diet or high salt diet (HS: 2, 4, and 8% NaCl) to construct the renal function curve. Na/K-ATPase signaling including c-Src and ERK1/2 phosphorylation, as well as protein carbonylation (a commonly used marker for enhanced ROS production), were assessed in the kidney cortex tissues by Western blot. Urinary and plasma Na⁺ levels were measured by flame photometry. When compared to B6 mice, TH mice developed salt-sensitive hypertension and responded to a high salt diet with a significant rise in systolic blood pressure indicative of a blunted pressure-natriuresis relationship. These findings were evidenced by a decrease in total and fractional Na⁺ excretion and a right-shifted renal function curve with a reduced slope. This salt-sensitive hypertension correlated with changes in the Na/K-ATPase signaling. Specifically, Na/K-ATPase signaling was not able to be stimulated by HS due to the activated baseline protein carbonylation, phosphorylation of c-Src and ERK1/2. These findings support the emerging view that Na/K-ATPase signaling contributes to metabolic disease and suggest that malfunction of the Na/K-ATPase signaling may promote the development of salt-sensitive hypertension in obesity. The increased basal level of renal Na/K-ATPase-dependent redox signaling may be responsible for the development of salt-sensitive hypertension in polygenic obese TH mice.

Deciphering the Allosteric Effect of Antagonist Vismodegib on Smoothened Receptor Deactivation Using Metadynamics Simulation

The smoothened receptor (Smo) plays a key role in Hedgehog (Hh) signaling pathway and it has been regarded as an efficacious therapeutic target for basal cell carcinoma (BCC) and medulloblastoma (MB). Nevertheless, the resistance mutation and active mutants of Smo have put forward the requirement of finding more effective inhibitors. Herein, we performed metadynamics simulations on Smo bound with vismodegib (Smo-Vismod) and with cholesterol (Smo-CLR), respectively, to explore the inhibition mechanism of vismodegib. The simulation results indicated that vismodegib-induced shifts of TM5, TM6, and TM7, which permitted the extracellular extension of TM6 and extracellular loop3 (ECL3) to enter the extracellular cysteine-rich domain (CRD) groove. Therefore, an open CRD groove that has not been noticed previously was observed in Smo-Vismod complex. As a consequence, the occupied CRD groove prevents the binding of cholesterol. In addition, the HD and ECLs play crucial roles in the interaction of CRD and TMD. These results reveal that TM5, TM6, and TM7 play important roles in allosteric inhibition the activation of Smo and disrupting cholesterol binding by vismodegib binding. Our results are expected to contribute to understanding the allosteric inhibition mechanism of Smo by vismodegib. Moreover, the detailed conformational changes contribute to the development of novel Smo inhibitors against resistance mutation and active mutants of Smo.

Prediction of the Antioxidant Response Elements' Response of Compound by Deep Learning

The antioxidant response elements (AREs) play a significant role in occurrence of oxidative stress and may cause multitudinous toxicity effects in the pathogenesis of a variety of diseases. Determining if one compound can activate AREs is crucial for the assessment of potential risk of compound. Here, a series of predictive models by applying multiple deep learning algorithms including deep neural networks (DNN), convolution neural networks (CNN), recurrent neural networks (RNN), and highway networks (HN) were constructed and validated based on Tox21 challenge dataset and applied to predict whether the compounds are the activators or inactivators of AREs. The built models were evaluated by various of statistical parameters, such as sensitivity, specificity, accuracy, Matthews correlation coefficient (MCC) and receiver operating characteristic (ROC) curve. The DNN prediction model based on fingerprint features has best prediction ability, with accuracy of 0.992, 0.914, and 0.917 for the training set, test set, and validation set, respectively. Consequently, these robust models can be adopted to predict the ARE response of molecules fast and accurately, which is of great significance for the evaluation of safety of compounds in the process of drug discovery and development.

Identification of novel genes that promote persister formation by repressing transcription and cell division in Pseudomonas aeruginosa

Objectives

Bacterial persisters are a small subpopulation of cells that are highly tolerant of antibiotics and contribute to chronic and recalcitrant infections. Global gene expression in Pseudomonas aeruginosa persister cells and genes contributing to persister formation remain largely unknown. The objective of this study was to examine the gene expression profiles of the persister cells and those that regained growth in fresh medium, as well as to identify novel genes related to persister formation.

Methods

P. aeruginosa persister cells and those that regrew in fresh medium were collected and subjected to RNA sequencing analysis. Genes up-regulated in the persister cells were overexpressed to evaluate their roles in persister formation. The functions of the persister-contributing genes were assessed with pulse–chase assay, affinity chromatography, fluorescence and electron microscopy, as well as a light-scattering assay.

Results

An operon containing PA2282–PA2287 was up-regulated in the persister cells and down-regulated in the regrowing cells. PA2285 and PA2287 play key roles in persister formation. PA2285 and PA2287 were found to bind to RpoC and FtsZ, which are involved in transcription and cell division, respectively. Pulse–chase assays demonstrated inhibitory effects of PA2285 and PA2287 on the overall transcription. Meanwhile, light-scattering and microscopy assays demonstrated that PA2285 and PA2287 interfere with cell division by inhibiting FtsZ aggregation. PA2285 and PA2287 are conserved in pseudomonads and their homologous genes in Pseudomonas putida contribute to persister formation.

Conclusions

PA2285 and PA2287 are novel bifunctional proteins that contribute to persister formation in P. aeruginosa.

NEET Proteins: A New Link Between Iron Metabolism, Reactive Oxygen Species, and Cancer

SIGNIFICANCE

Cancer cells accumulate high levels of iron and reactive oxygen species (ROS) to promote their high metabolic activity and proliferation rate. However, high levels of iron and ROS can also lead to enhanced oxidative stress and the activation of cell death pathways such as apoptosis and ferroptosis. This has led to the proposal that different drugs that target iron and/or ROS metabolism could be used as anticancer drugs. However, due to the complex role iron and ROS play in cells, the majority of these drugs yielded mixed results, highlighting a critical need to identify new players in the regulation of iron and ROS homeostasis in cancer cells. Recent Advances: NEET proteins belong to a newly discovered class of iron-sulfur proteins (2Fe-2S) required for the regulation of iron and ROS homeostasis in cells. Recent studies revealed that the NEET proteins NAF-1 (CISD2) and mitoNEET (CISD1) play a critical role in promoting the proliferation of cancer cells, supporting tumor growth and metastasis. Moreover, the function of NEET proteins in cancer cells was found to be dependent of the degree of lability of their 2Fe-2S clusters.

CRITICAL ISSUES

NEET proteins could represent a key regulatory link between the maintenance of high iron and ROS in cancer cells, the activation of cell death and survival pathways, and cellular proliferation.

FUTURE DIRECTIONS

Because the function of NEET proteins depends on the lability of their clusters, drugs that target the 2Fe2S clusters of NEET proteins could be used as promising anticancer drugs.

Growing Trends of Contralateral Prophylactic Mastectomy and Reconstruction in Young Breast Cancer

BACKGROUND

The aim of this study was to evaluate the trends of surgical treatments among young patients in T₁N_0-1M₀ stage based on the Surveillance, Epidemiology, and End Results database.

MATERIALS AND METHODS

Patients aged less than 40 y diagnosed between 1998 and 2015 were enrolled, with tumors in T₁N_0-1M₀ stage and not located in the central area. Differences in clinical-pathological characteristics were evaluated using chi-square tests. Multivariate logistic regression was used to measure the various factors associated with contralateral prophylactic mastectomy (CPM). Independent prognostic factors were evaluated by Cox model.

RESULTS

The total rate of breast-conserving surgery (BCS) was 51.6%, which declined from 64.5% in 1998 to 39.6% in 2015. The total rate of CPM was 22.7%, which increased from 3.7% in 1998 to 38.7% in 2014 despite a decline to 32.7% in 2015. Meanwhile, the rate of reconstruction increased in line with that of CPM, from 9.4% in 1998 to 35.0% in 2015. There was a trend of increasing use of implant-based reconstruction. Significant higher odds of CPM were found in recent year of diagnosis between 2010 and 2015 and in implant-based reconstruction. Patients undergoing CPM had similar survival outcomes compared with those undergoing BCS and unilateral mastectomy, whereas those undergoing BCS had better survival outcomes compared with those undergoing unilateral mastectomy.

CONCLUSIONS

A trend of growing preference for CPM and reconstruction was observed among young patients in early stage in recent years without survival benefits. Efforts should be made to promote efficient communication and evidence-based decision-making.

RNA Binding Motif Protein 48 Is Required for U12 Splicing and Maize Endosperm Differentiation

The last eukaryotic common ancestor had two classes of introns that are still found in most eukaryotic lineages. Common U2-type and rare U12-type introns are spliced by the major and minor spliceosomes, respectively. Relatively few splicing factors have been shown to be specific to the minor spliceosome. We found that the maize (Zea mays) RNA binding motif protein 48 (RBM48) is a U12 splicing factor that functions to promote cell differentiation and repress cell proliferation. RBM48 is coselected with the U12 splicing factor, zinc finger CCCH-type, RNA binding motif, and Ser/Arg rich 2/Rough endosperm 3 (RGH3). Protein-protein interactions between RBM48, RGH3, and U2 Auxiliary Factor (U2AF) subunits suggest major and minor spliceosome factors required for intron recognition form complexes with RBM48. Human RBM48 interacts with armadillo repeat containing 7 (ARMC7). Maize RBM48 and ARMC7 have a conserved protein-protein interaction. These data predict that RBM48 is likely to function in U12 splicing throughout eukaryotes and that U12 splicing promotes endosperm cell differentiation in maize.

[Meta-analysis on safety and efficacy of dual antiplatelet therapy combining with proton pump inhibitors for patients after percutaneous coronary intervention]

Objective: To analyze the impact of dual antiplatelet (DAPT) therapy combining with or without proton pump inhibitors (PPI) on the main outcomes after percutaneous coronary intervention (PCI). Methods: The PubMed, EMBASE and Cochrane Library were searched for relevant literature and the references obtained from these sources were retrieved manually from inception till September 2017. Inclusion and exclusion criteria were established follow the Cochrane review standard. A total of 977 literatures were included, 193 duplicates were excluded, 74 reviews, case reports, letters and systematic reviews were excluded, 667 literatures were excluded after reading the title and abstract, 34 literatures were excluded due to non-randomized control studies and unrelated outcome indicators, and 9 literatures were finally included with a total of 16 589 patients. RevMan 5.3 software was used to compare the incidence of major adverse cardiovascular events (MACE), cardiogenic death, recurrent myocardial infarction, target vessel revascularization, all-cause death, stent thrombosis, stroke, gastrointestinal bleeding and gastrointestinal events in patients with DAPT combining with or without PPI after PCI. Results: MACE was observed in 8 out of the 9 included literatures, and the results showed that MACE occurred in 561 out of 6 282 patients receiving DAPT combining with PPI therapy and in 951 out of 9 632 patients using DAPT alone (OR=1.15, 95%CI 0.88-1.51, P>0.05). Cardiogenic death was observed in 7 out of the 9 included literatures, and the results showed that cardiogenic death occurred in 172 out of 6 453 patients receiving DAPT combining with PPI treatment and in 321 out of the 9 839 patients using DAPT alone (OR=0.97, 95%CI 0.80-1.18, P>0.05). Recurrent myocardial infarction was observed in 7 out of the 9 included literatures, the results showed 416 out of 6 282 cases in DAPT combining with PPI therapy group experienced recurrent myocardial infarction and 691 out of 9 632 cases in DAPT group experienced recurrent myocardial infarction (OR=1.01, 95%CI 0.89-1.16, P>0.05). Four out of 9 literatures observed revascularization. The results showed that revascularization was performed in 64 out of 2 173 patients receiving DAPT combining with PPI therapy and in 105 out of the 2 770 patients using DAPT alone (OR=1.33, 95%CI 0.55-3.24, P>0.05). All-cause death was observed in 7 out of the 9 included literatures, and the results showed that all-cause death occurred in 172 out of the 6 453 patients in DAPT combining with PPI therapy group and in 321 out of the 9 839 patients using DAPT alone (OR=0.97, 95%CI 0.80-1.18, P>0.05). Three out of the 9 included articles observed stent thrombosis, and the results showed that stent thrombosis occurred in 99 out of 2 997 patients receiving DAPT combining with PPI therapy and in 245 out of the 6 198 patients treated with DAPT (OR=1.07, 95%CI 0.83-1.37, P>0.05). Stroke was observed in 2 out of the 9 included literatures. The results showed that stroke occurred in 5 out of 2 019 patients receiving DAPT combining with PPI therapy, and in 4 out of the 2 033 patients treated with DAPT (OR=1.00, 95%CI 0.29-3.49, P>0.05). Gastrointestinal bleeding was observed in 6 out of the 9 included literatures. The results showed that gastrointestinal bleeding occurred in 26 out of 3 517 patients receiving DAPT combined with PPI therapy, and in 93 out of the 3 506 patients treated with DAPT, gastrointestinal bleeding was significantly lower in the DAPT combining with PPI group than DAPT alone group (OR=0.27, 95%CI 0.17-0.41, P<0.01). Gastrointestinal events were reported in 6 out of the 9 included articles. Similarly, gastrointestinal events were observed in 51 out of 3 517 patients receiving DAPT combined with PPI therapy, and in 190 out of the 3 506 patients treated with DAPT alone, the incidence of gastrointestinal events in the DAPT combined with PPI group was significantly lower than DAPT alone group (OR=0.24, 95%CI 0.14-0.42, P<0.01). Conclusions: The incidence of MACE, cardiogenic death, recurrent myocardial infarction, target vessel revascularization, all-cause death, stent thrombosis and stroke are not affected by DAPT combined with PPI therapy after PCI, while the incidence of gastrointestinal bleeding and gastrointestinal events could be reduced by adding PPI to DAPT in patients undergoing PCI.

Abstract WP518: Use of American Heart Association/American Stroke Association Secondary Stroke Prevention Recommendations in Hispanic/Latino Adults With Stroke/TIA: The Hispanic Community Health Study/Study of Latinos

Background: Population studies showed that Hispanic/Latino adults have elevated rates of uncontrolled cardiovascular risk factors (CVRFs) with noticeable sex-specific variations . We investigated prevalence of CVRFs and the use of American Heart Association (AHA) secondary stroke prevention strategies in Hispanics/Latinos in the United States.

Methods: Data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) were used to examine sociodemographic characteristics, use of antithrombotic agents and statins, and treatment of CVRFs in persons with a history of stroke or transient ischemic attack (TIA). CVRFs were categorized as “controlled” if the CVRF met the goals defined by the AHA irrespective of whether the subject was on treatment for it or not; and “unaware” if the participant denied having a CVRF but met the diagnostic criteria for it. Differences between men and women were tested using ANOVA test and Pearson’s χ 2 . Factors associated with adherence to AHA recommendations were investigated using logistic regression.

Results: These analyses included 404 individuals with history of stroke/TIA (men=159; women=245). Women were slightly older than men (55.1±1.5 vs. 54.1±1.6 years; p<0.0001). The prevalence of hypertension (HTN), hypercholesterolemia (HC), and diabetes (DM) were 59%, 65% and 39%. The rates of awareness/controlled CVRFs were 90%/49%, 75%/32%, and 83%/54% for HTN, HC, and DM, respectively. Approximately 49% of the individuals were on antithrombotic agents, 39% on statins, and 26% on dual treatment with antithrombotics and statins. Rates were comparable between men and women except for HC control which was lower in women (41±6% vs. 23±5%; p=0.02). In logistic regression analysis, older age was associated with poorer adherence to AHA recommendations. Female sex and residence >10 years in the US were associated with uncontrolled HC and DM, respectively.

Conclusion: Hispanics/Latinos with stroke have elevated rates of awareness but suboptimal use of AHA secondary stroke prevention strategies. Older persons and women are vulnerable groups that may benefit from targeted interventions.

NrtR Regulates the Type III Secretion System Through cAMP/Vfr Pathway in Pseudomonas aeruginosa

The type III secretion system (T3SS) plays an important role in the pathogenesis of Pseudomonas aeruginosa. Expression of the T3SS is controlled under a complicate regulatory network. In this study, we demonstrate that NrtR (PA4916) is involved in the T3SS expression and pathogenesis of P. aeruginosa in a mouse acute pneumonia model. Overexpression of the T3SS central activator ExsA or exogenous supplementation of cAMP restored the expression of T3SS in the ΔnrtR mutant, suggesting that NrtR might regulate T3SS through the cAMP-Vfr signaling pathway. Further experiments demonstrated that the decrease of cAMP content is not due to the expression change of adenylate cyclases or phosphodiesterase in the ΔnrtR mutant. As it has been shown that nadD2 is upregulated in the ΔnrtR mutant, we overexpressed nadD2 in wild type PAK, which reduced the intracellular cAMP level and the expression of the T3SS genes. Meanwhile, deletion of nadD2 in the ΔnrtR mutant restored the expression and secretion of the T3SS. Co-immunoprecipitation assay revealed an interaction between NadD2 and the catalytic domain of the adenylate cyclase CyaB. Further in vitro assay indicated that NadD2 repressed the enzymatic activity of CyaB. Therefore, we have identified a novel regulatory mechanism of T3SS in P. aeruginosa.

The binding proximity of methyl β-lilacinobioside isolated from Caralluma retrospiciens with topoisomerase II attributes apoptosis in breast cancer cell line

The alterations in somatic genomes that controls the mechanism of cell division as a main cause of cancer, and then the drug that specifically toxic to the cancer cells further complicates the process of the development of the widely effective potential anticancer drug. The side effects of the drug as well as the radiotherapy used for the treatment of cancer is severe; therefore, the search of the natural products from the sources of wild plants having anticancer potential is become immense importance today. The ethno-medicinal survey undertaken in Al-Fayfa and Wadi-E-Damad region of southern Saudi Arabia revealed that the Caralluma retrospiciens (Ehrenb.) N.E.Br. (family Apocynaceae) is being used for the treatment of cancer by the native inhabitants. The biological evaluation of anticancer potential of bioassay-guided fractionations of methanolic extract of whole plant of C. retrospiciens against human breast adenocarcinoma cell line (MCF-7) followed by characterization using spectroscopic methods confirmed the presence of methyl β-lilacinobioside, a novel active constituent reported for the first time from C. retrospiciens, is capable of inhibition of cell proliferation and induction of apoptosis in MCF-7 cells by regulating ROS mediated autophagy, and thus validated the folkloric claim. Based on a small-scale computational target screening, Topoisomerase II was identified as the potential binding target of methyl β-lilacinobioside.

Preventing secondary exposure to women from men applying a novel nestorone/testosterone contraceptive gel

BACKGROUND

Testosterone (T)/Nestorone (NES) combination gel is a potential transdermal male contraceptive that suppresses gonadotropins and spermatogenesis. Transfer of transdermal T from men to women can be prevented by washing or covering application sites with clothing.

OBJECTIVES

We hypothesized that showering or wearing a shirt over gel application sites would prevent secondary exposure of T and NES to a woman after close skin contact.

MATERIALS AND METHODS

Twelve healthy male and 12 healthy female participants were recruited. Men applied T/NES 62 mg/8 mg gel to their shoulders and upper arms. Two hours after application, female partners rubbed the application site for 15 min. Exposure in the female partner was assessed under three conditions: a shirt covered the application site; the man showered prior to skin contact; or without intervention to reduce transfer. Serum T and NES concentrations were measured by LC-MS/MS in serial blood samples for 24 h after gel exposure.

MAIN OUTCOMES

Change in female serum T and NES levels as measured by average concentration over 24 h (C_avg ).

RESULTS

Median female serum T C_avg was 23.9 ng/dL (interquartile range, 19.3, 33.9) with the shirt barrier and 26.7 ng/dL (20.7, 33.9) after showering, which was higher than baseline 20.9 ng/dL (16.7, 25.0), both p < 0.03) but lower than without intervention (58.2 ng/dL [30.9, 89.1], both p < 0.01). Female serum NES C_avg and maximum concentration were below the lower limit of quantification with the shirt barrier and after showering, but increased without intervention in six of 12 women (maximum concentration <60 pg/mL). Men had lower average serum NES levels after showering (47 pg/ml [20, 94] compared to no intervention (153.3 pg/mL [51, 241], p < 0.02).

CONCLUSION

Secondary transfer of T and NES occurs after intensive skin contact with the gel application site. Secondary transfer is decreased by a shirt barrier or showering before contact.

Immediate Breast Reconstruction in De Novo Metastatic Breast Cancer: An Analysis of 563 Cases Based on the SEER Database

BACKGROUND

Controversy exists regarding the appropriateness of immediate breast reconstruction (IBR) in patients with metastatic breast cancer (MBC).

PATIENTS AND METHODS

By using the Surveillance, Epidemiology, and End Results (SEER) database, data of patients with de novo MBC undergoing mastectomy with or without IBR were assessed. The trend of IBR in de novo MBC was explored. Comparisons of the distribution of clinicopathologic characteristics were evaluated by chi-square and Fisher exact tests. The predictors of IBR in de novo MBC were evaluated by multivariate logistic regression. The survival outcomes were compared by Cox hazards models adjusting for known clinicopathologic variables in both the entire population and in the matched cohorts.

RESULTS

Between 1998 and 2015, 5.2% of patients with de novo MBC undergoing mastectomy received IBR. The rate of IBR increased significantly, from 6.3% in 1998 to 16.8% in 2015. Patients undergoing IBR were younger and had smaller tumor size, fewer positive lymph nodes, lower proportion of hormone receptor-negative disease and lung metastasis, and better economic status. They were also more likely to receive radiotherapy and chemotherapy. Although IBR was an independent favorable prognostic factor for breast cancer-specific survival and overall survival in the whole population, there were no statistically significant differences between IBR and mastectomy for breast cancer-specific survival (P = .892) and overall survival (P = .708) in the well-matched analysis.

CONCLUSION

IBR in selected de novo MBC could be an acceptable practice when balancing quality of life, underlying health care burden, and oncologic risks.

The anti-apoptotic proteins NAF-1 and iASPP interact to drive apoptosis in cancer cells

We reveal a novel interaction between the two anti-apoptotic proteins iASPP and NAF-1, which are overexpressed in many types of cancer cells, and propose that this interaction is required for apoptosis activation in cancer cells. A peptide derived from the interaction interface inhibits apoptosis in cells.

Suppression of apoptosis is a key Hallmark of cancer cells, and reactivation of apoptosis is a major avenue for cancer therapy. We reveal an interaction between the two anti-apoptotic proteins iASPP and NAF-1, which are overexpressed in many types of cancer cells and tumors. iASPP is an inhibitory member of the ASPP protein family, whereas NAF-1 belongs to the NEET 2Fe–2S protein family. We show that the two proteins are stimulated to interact in cells during apoptosis. Using peptide array screening and computational methods we mapped the interaction interfaces of both proteins to residues 764–778 of iASPP that bind to a surface groove of NAF-1. A peptide corresponding to the iASPP 764–780 sequence stabilized the NAF-1 cluster, inhibited NAF-1 interaction with iASPP, and inhibited staurosporine-induced apoptosis activation in human breast cancer, as well as in PC-3 prostate cancer cells in which p53 is inactive. The iASPP 764–780 IC₅₀ value for inhibition of cell death in breast cancer cells was 13 ± 1 μM. The level of cell death inhibition by iASPP 764–780 was altered in breast cancer cells expressing different levels and/or variants of NAF-1, indicating that the peptide activity is associated with NAF-1 function. We propose that the interaction between iASPP and NAF-1 is required for apoptosis activation in cancer cells. This interaction uncovers a new layer in the highly complex regulation of cell death in cancer cells and opens new avenues of exploration into the development of novel anticancer drugs that reactivate apoptosis in malignant tumors.

HigB Reciprocally Controls Biofilm Formation and the Expression of Type III Secretion System Genes through Influencing the Intracellular c-di-GMP Level in Pseudomonas aeruginosa

Toxin-antitoxin (TA) systems play important roles in bacteria persister formation. Increasing evidence demonstrate the roles of TA systems in regulating virulence factors in pathogenic bacteria. The toxin HigB in Pseudomonas aeruginosa contributes to persister formation and regulates the expression of multiple virulence factors and biofilm formation. However, the regulatory mechanism remains elusive. In this study, we explored the HigB mediated regulatory pathways. We demonstrate that HigB decreases the intracellular level of c-di-GMP, which is responsible for the increased expression of the type III secretion system (T3SS) genes and repression of biofilm formation. By analyzing the expression levels of the known c-di-GMP metabolism genes, we find that three c-di-GMP hydrolysis genes are up regulated by HigB, namely PA2133, PA2200 and PA3825. Deletion of the three genes individually or simultaneously diminishes the HigB mediated regulation on the expression of T3SS genes and biofilm formation. Therefore, our results reveal novel functions of HigB in P. aeruginosa.

Accurate measurement of androgen after androgen esters: problems created by ex vivo esterase effects and LC-MS/MS interference

Background

Ex vivo androgen prodrug conversion by blood esterases after oral androgen ester administration may result in an overestimation of the measured blood androgens.

Objective

We investigated whether blood collection tubes with esterase inhibitors decreased the conversion of testosterone undecanoate (TU) and dimethandrolone undecanoate (DMAU) to their active metabolites, testosterone (T), and dimethandrolone (DMA), providing a more accurate assessment of circulating T/DMA levels.

Methods

Blood was collected in tubes with/without esterase inhibitors from: (i) four healthy and four hypogonadal men receiving no androgens and spiked ex vivo with TU/DMAU; (ii) four men taking oral TU (Andriol^®); and (iii) eight hypogonadal men dosed with oral 316 mg TU and 15 healthy men with 200 mg DMAU. T/DMA levels were measured by LC‐MS/MS.

Results

Sodium fluoride (NaF, an esterase inhibitor) decreased measured T levels by 14.2% in men not receiving TU. Increasing amounts of TU/DMAU added to blood collected into plain tubes resulted in a concentration‐dependent overestimation of T/DMA that was reduced by collecting blood into NaF tubes (by 30–85%), and keeping samples at 4 °C and minimizing time prior to centrifugation. After oral TU/DMAU administration to men, when TU/DMAU levels were >15/10 ng/mL, respectively, blood collected in NaF tubes yielded lower measured T concentrations by 15–30% and DMA by 22% due to an additional inhibitory effect of NaF on blood esterases.

Conclusion

NaF directly lowers plasma T/DMA levels measured by LC‐MS/MS and also inhibits blood esterase activity. Overestimation of T/DMA in blood collected in tubes without NaF after oral TU/DMAU administration is important for pharmacokinetics studies in drug development clinical trials but may have limited impact in clinical practice/utilization because the differences between measured and true androgen values are modest and the wide therapeutic androgen efficacy ranges obviate the need for highly accurate androgen measurements during therapy.

miR-330-3p promotes lung cancer cells invasion, migration, and metastasis by directly targeting hSOD2b

Lung cancer is a serious threat to human health. Studies have revealed that human manganese superoxide dismutase (hSOD2) and miRNAs play an essential role in the metastasis process of lung cancer. However, the miRNAs that associated with hSOD2 and involved in metastasis, remain elusive. After databases analysis and dual luciferase reporter validation, we demonstrated that miR-330-3p expression inversely correlated with hSOD2b expression level, and that miR-330-3p directly targeted the 3'untranslated region (3'UTR) of hSOD2b. Furthermore, overexpression of miR-330-3p promoted whereas knockdown of miR-330-3p inhibited invasion/migration and the epithelial-mesenchymal transition (EMT) process of lung cancer cells in vitro. Knockdown of miR-330-3p inhibited metastasis of lung cancer cells in vivo. Moreover, miR-330-3p-mediated enhancement of invasion/migration in 95-D cells could be rescued by over-expression of hSOD2. In conclusion, we demonstrated that miR-330-3p promoted metastasis of lung cancer cells by suppressing hSOD2b expression and unveiled a new clinical application of miR-330-3p in the therapy of lung cancer.

MicroRNA-647 promotes the therapeutic effectiveness of argon-helium cryoablation and inhibits cell proliferation through targeting TRAF2 via the NF-κB signaling pathway in non-small cell lung cancer

Background

MicroRNA-647 (miR-647) has been reported to repress cell tumorigenic phenotype, while the function of miR-647 in non-small cell lung cancer was obscure.

Methods

The effect of miR-647 and TRAF2 on A549 and H1299 cells was explored through Methyl thiazolyl tetrazolium (MTT) assay, colony formation and cell cycle assays. Luciferase reporter assays, reverse transcription quantitative PCR (RT-qPCR) and Western blot assay were carried out to determine that TRAF2 is directly regulated by miR-647. The effect of miR-647/TRAF2 axis on p65 protein level in nucleus or total was detected by Western blot assay.

Results

Here, we found that miR-647 was high expression in tumor that under argon-helium cryoablation treatment in contrast to the tumor under non argon-helium cryoablation treatment and inhibited cell proliferation of A549 and H1299 cells by inducing G1-S transition. TRAF2 was confirmed as a target of miR-647. TRAF2 overexpression partially rescued the suppressive function of miR-647 in A549 and H1299 cells. Moreover, we found that miR-647 repressed lung carcinogenesis by attenuating NF-κB pathway.

Conclusion

In all, our study demonstrates that miR-647 functions as tumor suppressor via targeting and down-regulating the expression of TRAF2 and NF-κB signaling pathway in non-small cell lung cancer.

Many Analysts, One Data Set: Making Transparent How Variations in Analytic Choices Affect Results

Twenty-nine teams involving 61 analysts used the same data set to address the same research question: whether soccer referees are more likely to give red cards to dark-skin-toned players than to light-skin-toned players. Analytic approaches varied widely across the teams, and the estimated effect sizes ranged from 0.89 to 2.93 ( Mdn = 1.31) in odds-ratio units. Twenty teams (69%) found a statistically significant positive effect, and 9 teams (31%) did not observe a significant relationship. Overall, the 29 different analyses used 21 unique combinations of covariates. Neither analysts’ prior beliefs about the effect of interest nor their level of expertise readily explained the variation in the outcomes of the analyses. Peer ratings of the quality of the analyses also did not account for the variability. These findings suggest that significant variation in the results of analyses of complex data may be difficult to avoid, even by experts with honest intentions. Crowdsourcing data analysis, a strategy in which numerous research teams are recruited to simultaneously investigate the same research question, makes transparent how defensible, yet subjective, analytic choices influence research results.

Construction of a Protective Vaccine Against Lipopolysaccharide-Heterologous Pseudomonas aeruginosa Strains Based on Expression Profiling of Outer Membrane Proteins During Infection

Pseudomonas aeruginosa is a ubiquitous opportunistic pathogen, which causes infectious disease in patients with cystic fibrosis and compromised immunity. P. aeruginosa is difficult to eradicate because of its intrinsic resistance to most traditional antibiotics as well as acquired resistance mechanisms after decades of antibiotic usage. A full understanding of the P. aeruginosa pathogenesis mechanisms is necessary for the development of novel prevention and treatment strategies. To identify novel vaccine candidates, here we comprehensively examined the expression levels of all the known outer membrane proteins in two P. aeruginosa strains in a murine acute pneumonia model. OprH was one of the most highly expressed proteins during infection. In addition, OprH is known to be highly immunogenic and accessible by host proteins. Thus, it was chosen as a vaccine candidate. To further identify vaccine candidates, 34 genes highly expressed during infection were evaluated for their contributions in virulence by testing individual transposon insertion mutants. Among them, fpvA, hasR, and foxA were found essential for bacterial virulence and therefore included in vaccine construction. Immunization with a mixture of FpvA, HasR, and FoxA rendered no protection, however, while immunization by OprH refolded in liposomes elicited specific opsonic antibodies and conferred protection against two lipopolysaccharide-heterologous P. aeruginosa strains (PA14 and PA103). Overall, by studying the expression profile of the P. aeruginosa outer membrane proteins during infection, we identified OprH as a potential vaccine candidate for the prevention of lung infection by P. aeruginosa.

A Statistical Thermodynamic Model for Ligands Interacting With Ion Channels: Theoretical Model and Experimental Validation of the KCNQ2 Channel

Ion channels are important therapeutic targets, and their pharmacology is becoming increasingly important. However, knowledge of the mechanism of interaction of the activators and ion channels is still limited due to the complexity of the mechanisms. A statistical thermodynamic model has been developed in this study to characterize the cooperative binding of activators to ion channels. By fitting experimental concentration-response data, the model gives eight parameters for revealing the mechanism of an activator potentiating an ion channel, i.e., the binding affinity (K_A), the binding cooperative coefficients for two to four activator molecules interacting with one channel (γ, μ, and ν), and the channel conductance coefficients for four activator binding configurations of the channel (a, b, c, and d). Values for the model parameters and the mechanism underlying the interaction of ztz240, a proven KCNQ2 activator, with the wild-type channel have been obtained and revealed by fitting the concentration-response data of this activator potentiating the outward current amplitudes of KCNQ2. With these parameters, our model predicted an unexpected bi-sigmoid concentration-response curve of ztz240 activation of the WT-F137A mutant heteromeric channel that was in good agreement with the experimental data determined in parallel in this study, lending credence to the assumptions on which the model is based and to the model itself. Our model can provide a better fit to the measured data than the Hill equation and estimates the binding affinity, as well as the cooperative coefficients for the binding of activators and conductance coefficients for binding states, which validates its use in studying ligand-channel interaction mechanisms.

PutA Is Required for Virulence and Regulated by PruR in Pseudomonas aeruginosa

Pseudomonas aeruginosa, a Gram-negative opportunistic pathogenic bacterium, causes acute and chronic infections. Upon entering the host, P. aeruginosa alters global gene expression to adapt to host environment and avoid clearance by the host immune system. Proline utilization A (PutA) is a bifunctional enzyme, which converts proline to glutamate. Here we report that PutA was required for the virulence of P. aeruginosa in a murine acute pneumonia model. A putA mutant was more susceptible to oxidative stress compared to the wild type strain. An AraC/XylS family protein, PruR, directly bound to the upstream of −35 box in the putA promoter and activated putA expression. High concentration of proline in bacteria up-regulated pruR expression, which led to the activation of putA expression. As a feedback regulation, glutamate produced by PutA released PruR from the putA promoter and turned off the putA expression. PruR affected bacterial virulence through the regulation of the putA expression. Altogether, these data are the first to reveal that PutA plays an important role in the pathogenesis of P. aeruginosa, as well as to describe the genetic regulation of PutA in P. aeruginosa.

Development of liposomal pemetrexed for enhanced therapy against multidrug resistance mediated by ABCC5 in breast cancer

Purpose

Breast cancer is the most common cancer among women. Pemetrexed, a new generation antifolate drug, is one of the primary treatments for breast cancer. However, multidrug resistance (MDR) in breast cancer greatly hampers the therapeutic efficacy of chemotherapies such as pemetrexed. Nanomedicine is emerging as a promising alternative technique to overcome cancer MDR. Thus, pemetrexed-loaded d-alpha tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS) liposomes (liposomal pemetrexed) were developed as a strategy to overcome MDR to pemetrexed in breast cancer.

Materials and methods

Liposomal pemetrexed was developed using the calcium acetate gradient method. The cytotoxic effects, apoptosis-inducing activity, in vivo distribution, and antitumor activity of liposomal pemetrexed were investigated.

Results

Liposomal pemetrexed was small in size (160.77 nm), with a small polydispersity of <0.1. The encapsulation efficacy of liposomal pemetrexed was 63.5%, which is rather high for water-soluble drugs in liposomes. The IC₅₀ of liposomal pemetrexed following treatment with MDR breast cancer cells (MCF-7 cells overexpressing ABCC5) was 2.6-fold more effective than pemetrexed. The in vivo biodistribution study showed that the liposomes significantly accumulated in tumors 24 h after injection. The antitumor assay in mice bearing MDR breast cancer xenograft tumors confirmed the superior antitumor activity of liposomal pemetrexed over pemetrexed. It was also found that the improved therapeutic effect of liposomal pemetrexed may be attributed to apoptosis through both extrinsic and intrinsic pathways.

Conclusion

Liposomal pemetrexed represents a potential therapeutic approach for overcoming breast cancer MDR.

Targeting CPT1A-mediated fatty acid oxidation sensitizes nasopharyngeal carcinoma to radiation therapy

Nasopharyngeal carcinoma (NPC) has a particularly high prevalence in southern China, southeastern Asia and northern Africa. Radiation resistance remains a serious obstacle to successful treatment in NPC. This study aimed to explore the metabolic feature of radiation-resistant NPC cells and identify new molecular-targeted agents to improve the therapeutic effects of radiotherapy in NPC. Methods: Radiation-responsive and radiation-resistant NPC cells were used as the model system in vitro and in vivo. Metabolomics approach was used to illustrate the global metabolic changes. ¹³C isotopomer tracing experiment and Seahorse XF analysis were undertaken to determine the activity of fatty acid oxidation (FAO). qRT-PCR was performed to evaluate the expression of essential FAO genes including CPT1A. NPC tumor tissue microarray was used to investigate the prognostic role of CPT1A. Either RNA interference or pharmacological blockade by Etomoxir were used to inhibit CPT1A. Radiation resistance was evaluated by colony formation assay. Mitochondrial membrane potential, apoptosis and neutral lipid content were measured by flow cytometry analysis using JC-1, Annexin V and LipidTOX Red probe respectively. Molecular markers of mitochondrial apoptosis were detected by western blot. Xenografts were treated with Etomoxir, radiation, or a combination of Etomoxir and radiation. Mitochondrial apoptosis and lipid droplets content of tumor tissues were detected by cleaved caspase 9 and Oil Red O staining respectively. Liquid chromatography coupled with tandem mass spectrometry approach was used to identify CPT1A-binding proteins. The interaction of CPT1A and Rab14 were detected by immunoprecipitation, immunofluorescence and in situ proximity ligation analysis. Fragment docking and direct coupling combined computational protein-protein interaction prediction method were used to predict the binding interface. Fatty acid trafficking was measured by pulse-chase assay using BODIPY C16 and MitoTracker Red probe. Results: FAO was active in radiation-resistant NPC cells, and the rate-limiting enzyme of FAO, carnitine palmitoyl transferase 1 A (CPT1A), was consistently up-regulated in these cells. The protein level of CPT1A was significantly associated with poor overall survival of NPC patients following radiotherapy. Inhibition of CPT1A re-sensitized NPC cells to radiation therapy by activating mitochondrial apoptosis both in vitro and in vivo. In addition, we identified Rab14 as a novel CPT1A binding protein. The CPT1A-Rab14 interaction facilitated fatty acid trafficking from lipid droplets to mitochondria, which decreased radiation-induced lipid accumulation and maximized ATP production. Knockdown of Rab14 attenuated CPT1A-mediated fatty acid trafficking and radiation resistance. Conclusion: An active FAO is a vital signature of NPC radiation resistance. Targeting CPT1A could be a beneficial regimen to improve the therapeutic effects of radiotherapy in NPC patients. Importantly, the CPT1A-Rab14 interaction plays roles in CPT1A-mediated radiation resistance by facilitating fatty acid trafficking. This interaction could be an attractive interface for the discovery of novel CPT1A inhibitors.

Abstract P2-08-01: Loss of function of Brca1 or Gata3 induces basal-like breast cancer

BACKGROUND:

Breast cancer is mainly divided into estrogen receptor (ER)-positive luminal and ER-negative basal-like tumors. Luminal-type tumors are associated with better survival and respond to hormone therapies whereas basal-like tumors are more aggressive and associated with a poor prognosis. Mammary epithelia are mainly composed of luminal and basal cells that are maintained by luminal and basal progenitors, respectively. The maintenance of luminal cell fate is orchestrated by networks of transcription factors, including BRCA1 and GATA3. Functional loss of BRCA1 by germline or somatic mutation or by promoter methylation is associated with more than one third of basal-like breast cancers. GATA3 expression is reduced in basal-like breast cancers and cancers that metastasize. Overexpression of GATA3 in cancer cells inhibits tumor formation. Deletion of Brca1 or Gata3 in mice results in early lethality or growth defects. How BRCA1 and GATA3 suppress breast cancer remains elusive.

METHODS:

We generated mice lacking Brca1 or Gata3 in mammary epithelia. Due to the proliferative defects and induction of p18Ink4c (p18), an inhibitor of CDK4/6, in mammary epithelial cells of these mice, we then generated mice lacking Brca1 or Gata3 in p18 deficient mammary epithelia. We determined spontaneous mammary tumor development in mutant mice and the mechanisms underlying the role of Brca1 and Gata3 in suppressing tumorigenesis and progression.

RESULTS:

Depletion of Brca1 or Gata3 led to growth defects of mammary epithelial cells, which was rescued by loss of p18. Depletion of Brca1 or Gata3 in a p18 null background induced heterogeneous mammary tumors with less luminal and more basal-like features and accelerated metastasis. Deletion of Brca1 eliminated Gata3 expression in human and mouse mammary tissues and cells. How Brca1 interacts with Gata3 to control mammary tumor development and progression is currently under investigation.

CONCLUSION: Our results suggest that loss of function of either Brca1 or Gata3 induces basal-like mammary tumors in p18 deficient background.

Citation Format: Pei X-H, Chan HL, Zhang L, Wang C, Robbins DJ, Capobianco T, Bai F. Loss of function of Brca1 or Gata3 induces basal-like breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-08-01.

Bacterial type III secretion system as a protein delivery tool for a broad range of biomedical applications

A protein delivery tool based on bacterial type III secretion system (T3SS) has been broadly applied in biomedical researches. In this review, we summarize various applications of the T3SS-mediate protein delivery which enables translocation of proteins directly into mammalian cells without protein purification. Some of the remarkable advancements include delivery of antigens for therapeutic vaccines, nucleases for genome editing, transcription factors for cellular reprogramming and stem cells differentiation, and signaling molecules for post-translational proteomics studies. With continued improvement of the T3SS-mediated protein delivery tools, even wider application of the technology is anticipated.

Evolution of the prevalence of hepatitis C virus infection and hepatitis C virus genotype distribution in human immunodeficiency virus-infected patients in Italy between 1997 and 2015

OBJECTIVES

To analyse the variation of hepatitis C virus (HCV) prevalence and genotype distribution and their determinants in people living with human immunodeficiency virus (HIV) who entered care between 1997 and 2015.

METHODS

HIV-infected patients enrolled in ICONA who were tested for HCV antibodies (HCV-Ab) were included.

RESULTS

Overall 3407 of 12 135 (28.1%) were HCV-Ab+; and 735 of 12 135 (6.1%) were HBsAg+. Among patients whose HCV genotype was known, the most represented were genotypes 1 and 3. The prevalence of HCV infection decreased from 49.2% (2565/5217) during 1997-2002 to 10.2% (556/5466) during 2009-2015. The frequency of genotype 1a increased from 29.0% (264/911) to 43.0% (129/300), whereas genotype 3 decreased from 38.5% (351/911) to 27.0% (81/300). Independent predictors of HCV-Ab+ status were being female (adjusted OR (AOR) 1.23, 95% CI 1.04-1.50, p = 0.01), risk category (versus injecting drug users: men who have sex with men AOR 0.01, 95% CI 0.01-0.01, p <0.001; heterosexuals AOR 0.01, 95% CI 0.01-0.01, p <0.001; other/unknown AOR 0.02, 95% CI 0.01-0.02, p <0.001), being cared for in Central Italy (versus being cared for in Northern Italy: AOR 0.85, 95% CI 0.73-0.98, p <0.001), being Italian-born (AOR 1.44, 95% CI 1.16-1.80, p = 0.001) and being enrolled in less recent calendar years (versus 1997-2002: 2009-2015 AOR 0.23, 95% CI 0.19-0.27, p <0.001; 2003-2008 AOR 0.49, 95% CI 0.41-0.61, p <0.001).

CONCLUSIONS

The prevalence of HCV infection in HIV-infected patients entering into care in Italy significantly declined in more recent calendar years. After adjusting for risk factors and calendar years, HCV co-infection was more frequent in females and in those born in Italy.

Simultaneous Identification of Ten Bacterial Pathogens Using the Multiplex Ligation Reaction Based on the Probe Melting Curve Analysis

Pathogenic Vibrio spp., Aeromonas spp. and Plesiomonas shigelloides are associated with human gastroenteritis and wound infections, as well as fish diseases. The comprehensive and accurate identification of these pathogens is crucial for the current public health. The present study describes the development of a multiplex assay for the simultaneous identification of ten bacterial pathogens in a single reaction by using a multiplex ligation reaction based on probe melting curve analysis (MLMA). The specificity for target genes was 100%, as assessed with a panel of 67 bacterial pathogens, which indicated no cross-reactions. The detection limit of this assay ranged from 0.8 × 10⁷ CFU/mL to 1.5 × 10⁸ CFU/mL at the pure bacterial culture level and from 0.1 ng to 1.0 ng at the DNA level. The MLMA assay was used to detect ten species of pathogens in 269 clinical and seafood samples, and for further validation, the results were compared with the conventional culture method. The results indicated greater than 90% sensitivity and 100% specificity for each bacterial pathogen tested, and the kappa correlation for all the pathogens ranged from 0.95 to 1.00. Overall, this assay is well suited for public health laboratories for its high throughput, accuracy, and low cost.

Old canalicular laceration repair: a retrospective study of the curative effects and prognostic factors

AIM

To investigate the epidemiology and surgical outcomes of old canalicular laceration and analyze the variables impacting on the prognosis of reparation.

METHODS

A retrospective review of all old canalicular laceration repairs from Jan. 1, 2008 to Dec. 30, 2015 was performed. Analyzed data included demographics, mechanisms of injury, the time from injury to repair, causes for delayed repair, old associated injuries, the types of surgery, and the effects of repair using canaliculus anastomosis combined with bicanalicular stent intubation.

RESULTS

Totally 148 patients with old canalicular laceration received surgical repair and were enrolled. The mean age at presentation was 32.52 years old (ranged from 3 to 63 years old). The 110 patients (74.32%) were male and 127 patients (85.81%) were adults (≥18 years old). The old upper, lower, and bicanalicular lacerations were found in 5 (3.38%), 39 (26.35%), and 104 patients (70.27%), respectively. The mechanism of old injury was primarily due to motor vehicle accidents (n=53, 35.81%). The mean time from injury to repair was 43.61mo (ranged from 1 to 360mo). Associated old ocular and orbit injuries were found in 65 patients (43.92%), and chronic dacryocystitis in 18 patients (12.16%). The main cause of delayed repair was that doctors or patients didn't pay attention to the canalicular laceration because of the concurrent severe injuries (n=71, 47.97%). Totally 136 patients (91.89%) with old canalicular laceration underwent canaliculus anastomosis combined with bicanalicular stent intubation. In all of them, 20 patients (13.51%) were combined with dacryocystorhinostomy. In these cases, 132 patients (97.06%) attained anatomic success, 121 patients (88.97%) reported no epiphora (functional success), 11 patients (8.09%) reported significant epiphora anesis (functional improvement), and 4 (2.94%) reported no significant anesis (functional failure). Rates of anatomic success and functional success were significantly correlated with different canaliculus involved. However, rates of anatomic success and functional success were not significantly affected by the time from injury to repair.

CONCLUSION

The canalicular anastomosis combined with bicanalicular stent intubation could act as an effective therapeutics for old canalicular laceration.

Nonlinear modulation of interacting between COMT and depression on brain function

BACKGROUND

The catechol-O-methyltransferase (COMT) gene is related to dopamine degradation and has been suggested to be involved in the pathogenesis of major depressive disorder (MDD). However, how this gene affects brain function properties in MDD is still unclear.

METHODS

Fifty patients with MDD and 35 cognitively normal participants underwent a resting-state functional magnetic resonance imaging scan. A voxelwise and data-drive global functional connectivity density (gFCD) analysis was used to investigate the main effects and the interactions of disease states and COMT rs4680 gene polymorphism on brain function.

RESULTS

We found significant group differences of the gFCD in bilateral fusiform area (FFA), post-central and pre-central cortex, left superior temporal gyrus (STG), rectal and superior temporal gyrus and right ventrolateral prefrontal cortex (vlPFC); abnormal gFCDs in left STG were positively correlated with severity of depression in MDD group. Significant disease×COMT interaction effects were found in the bilateral calcarine gyrus, right vlPFC, hippocampus and thalamus, and left SFG and FFA. Further post-hoc tests showed a nonlinear modulation effect of COMT on gFCD in the development of MDD. Interestingly, an inverted U-shaped modulation was found in the prefrontal cortex (control system) but U-shaped modulations were found in the hippocampus, thalamus and occipital cortex (processing system).

CONCLUSION

Our study demonstrated nonlinear modulation of the interaction between COMT and depression on brain function. These findings expand our understanding of the COMT effect underlying the pathophysiology of MDD.

Compression Properties and Electrical Conductivity of In-Situ 20 vol.% Nano-Sized TiCx/Cu Composites with Different Particle Size and Morphology

The compression properties and electrical conductivity of in-situ 20 vol.% nano-sized TiC_x/Cu composites fabricated via combustion synthesis and hot press in Cu-Ti-CNTs system at various particles size and morphology were investigated. Cubic-TiC_x/Cu composite had higher ultimate compression strength (σ_UCS), yield strength (σ_0.2), and electric conductivity, compared with those of spherical-TiC_x/Cu composite. The σ_UCS, σ_0.2, and electrical conductivity of cubic-TiC_x/Cu composite increased by 4.37%, 20.7%, and 17.8% compared with those of spherical-TiC_x/Cu composite (526 MPa, 183 MPa, and 55.6% International Annealed Copper Standard, IACS). Spherical-TiC_x/Cu composite with average particle size of ~94 nm exhibited higher ultimate compression strength, yield strength, and electrical conductivity compared with those of spherical-TiC_x/Cu composite with 46 nm in size. The σ_UCS, σ_0.2, and electrical conductivity of spherical-TiC_x/Cu composite with average size of ~94 nm in size increased by 17.8%, 33.9%, and 62.5% compared with those of spherical-TiC_x/Cu composite (417 MPa, 121 MPa, and 40.3% IACS) with particle size of 49 nm, respectively. Cubic-shaped TiC_x particles with sharp corners and edges led to stress/strain localization, which enhanced the compression strength of the composites. The agglomeration of spherical-TiC_x particles with small size led to the compression strength reduction of the composites.

In vivo Host Environment Alters Pseudomonas aeruginosa Susceptibility to Aminoglycoside Antibiotics

During host infection, Pseudomonas aeruginosa coordinately regulates the expression of numerous genes to adapt to the host environment while counteracting host clearance mechanisms. As infected patients take antibiotics, the invading bacteria encounter antibiotics in the host milieu. P. aeruginosa is highly resistant to antibiotics due to multiple chromosomally encoded resistant determinants. And numerous in vitro studies have demonstrated the regulatory mechanisms of antibiotic resistance related genes in response to antibiotics. However, it is not well-known how host environment affects bacterial response to antibiotics. In this study, we found that P. aeruginosa cells directly isolated from mice lungs displayed higher susceptibility to tobramycin than in vitro cultured bacteria. In vitro experiments demonstrated that incubation with A549 and differentiated HL60 (dHL60) cells sensitized P. aeruginosa to tobramycin. Further studies revealed that reactive oxygen species produced by the host cells contributed to the increased bacterial susceptibility. At the same concentration of tobramycin, presence of A549 and dHL60 cells resulted in higher expression of heat shock proteins, which are known inducible by tobramycin. Further analyses revealed decreased membrane potential upon incubation with the host cells and modification of lipopolysaccharide, which contributed to the increased susceptibility to tobramycin. Therefore, our results demonstrate that contact with host cells increased bacterial susceptibility to tobramycin.

Protecting Effects of Gonadotropin-Releasing Hormone Agonist on Chemotherapy-Induced Ovarian Damage in Premenopausal Breast Cancer Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

There is no universal consensus on whether gonadotropin-releasing hormone (GnRH) agonist could protect chemotherapy-induced ovarian damage in premenopausal breast cancer patients. This meta-analysis was conducted to estimate the protective effects of GnRH agonist on premenopausal breast cancer patients in details.

METHODS

PubMed, Cochrane Library, Embase, CNKI and the Chinese Wangfang Database, conference proceedings and clinical trials were searched to find studies reported since 2000. Heterogeneity for the eligible data was assessed and a pooled odds ratio (OR) with 95% confidence interval (CI) was calculated.

RESULTS

Resumption of menses rate was improved in the GnRH agonist and chemotherapy-combination groups versus chemotherapy-alone groups (OR = 1.36, 95% CI: 1.19-1.56). Furthermore, the results indicated that spontaneous pregnancy rate was improved in the experimental groups versus the controls (OR = 1.90, 95% CI: 1.06-3.41). In addition, no publication bias was found using a Begg's funnel plot.

CONCLUSION

The results of the current meta-analysis indicate that a GnRH agonist could improve resumption of menses rate and pregnancy rate for premenopausal breast cancer patients. However, more evaluation may be considered to prove this theory.

Abstract P6-08-08: GATA3 inhibits breast basal-like tumorigenesis

BACKGROUND: Breast cancer can be broadly categorized into two groups depending on the cell type affected. Luminal-type tumors are typically estrogen receptor (ER) positive that are associated with better survival and respond to hormone therapies whereas basal-like tumors are ER negative, more aggressive, and associated with a poor prognosis. GATA3 is a transcription factor well studied for its role as a master regulator of cellular differentiation and stem cell self renewal. Loss of Gata3 in mouse mammary glands blocks luminal cell differentiation and induces growth defects, and low levels of GATA3 are associated with basal-like and metastatic human breast cancers with epithelial-to-mesenchymal transition (EMT). Importantly, luminal cells have been shown to be the origin of some basal-like breast cancers. Due to the proliferation defects caused by GATA3 deficiency, it remains elusive how loss of function of GATA3 contributes to breast cancers development and progression.

METHODS: We previously demonstrated that p18Ink4c (p18), a cell cycle inhibitor, is a downstream target of GATA3 in regulating mammary luminal cell proliferation and loss of p18 leads to luminal type tumorigenesis. To test the role of Gata3 deficiency in tumorigenesis, we generated p18-/-;Gata3+/- mice. Mammary gland development and tumorigenesis were characterized in vivo using a panel of cellular and molecular assays. Results were further confirmed in vitro with well established cell lines.

RESULTS: Loss of p18 rescued mammary growth defects caused by Gata3 heterozygosity. Gata3 heterozygosity impaired luminal, but promoted basal gene expression in mammary epithelial cells. Gata3 heterozygosity in p18 null mice accelerated spontaneous mammary tumorigenesis, reducing the average latency of tumor onset. More importantly, Gata3 heterozygosity transformed the luminal type tumors of p18 null mice into heterogeneous basal-like breast cancers with activated EMT. Conversely, reintroduction of GATA3 inhibited tumor growth and reduced expression of EMT markers in basal-like tumor xenografts. We discovered that expression of GATA3 and Vimentin, an EMT marker, is inversely related in human breast cancers.

CONCLUSION: Our data indicates that GATA3 promotes luminal but suppresses basal cell differentiation in the mammary gland and in tumor development.

Mechanisms underlying the role of GATA3 in suppressing basal-like tumor development are under investigation.BACKGROUND: Breast cancer can be broadly categorized into two groups depending on the cell type affected. Luminal-type tumors are typically estrogen receptor (ER) positive that are associated with better survival and respond to hormone therapies whereas basal-like tumors are ER negative, more aggressive, and associated with a poor prognosis. GATA3 is a transcription factor well studied for its role as a master regulator of cellular differentiation and stem cell self renewal. Loss of Gata3 in mouse mammary glands blocks luminal cell differentiation and induces growth defects, and low levels of GATA3 are associated with basal-like and metastatic human breast cancers with epithelial-to-mesenchymal transition (EMT). Importantly, luminal cells have been shown to be the origin of some basal-like breast cancers. Due to the proliferation defects caused by GATA3 deficiency, it remains elusive how loss of function of GATA3 contributes to breast cancers development and progression.

METHODS: We previously demonstrated that p18Ink4c (p18), a cell cycle inhibitor, is a downstream target of GATA3 in regulating mammary luminal cell proliferation and loss of p18 leads to luminal type tumorigenesis. To test the role of Gata3 deficiency in tumorigenesis, we generated p18-/-;Gata3+/- mice. Mammary gland development and tumorigenesis were characterized in vivo using a panel of cellular and molecular assays. Results were further confirmed in vitro with well established cell lines.

RESULTS: Loss of p18 rescued mammary growth defects caused by Gata3 heterozygosity. Gata3 heterozygosity impaired luminal, but promoted basal gene expression in mammary epithelial cells. Gata3 heterozygosity in p18 null mice accelerated spontaneous mammary tumorigenesis, reducing the average latency of tumor onset. More importantly, Gata3 heterozygosity transformed the luminal type tumors of p18 null mice into heterogeneous basal-like breast cancers with activated EMT. Conversely, reintroduction of GATA3 inhibited tumor growth and reduced expression of EMT markers in basal-like tumor xenografts. We discovered that expression of GATA3 and Vimentin, an EMT marker, is inversely related in human breast cancers.

CONCLUSION: Our data indicates that GATA3 promotes luminal but suppresses basal cell differentiation in the mammary gland and in tumor development.

Mechanisms underlying the role of GATA3 in suppressing basal-like tumor development are under investigation.

Citation Format: Pei X-H, Chan HL, Liu S, Scott A, Pimentel E, Slingerland J, Robbins D, Capobianco A, Bai F. GATA3 inhibits breast basal-like tumorigenesis [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-08-08.

An Experimental Analysis of the Molecular Effects of Trastuzumab (Herceptin) and Fulvestrant (Falsodex), as Single Agents or in Combination, on Human HR+/HER2+ Breast Cancer Cell Lines and Mouse Tumor Xenografts

Purpose

To investigate the effects of trastuzumab (herceptin) and fulvestrant (falsodex) either in combination or alone, on downstream cell signaling pathways in lab-cultured human HR+/HER2+ breast cancer cell lines ZR-75-1 and BT-474, as well as on protein expression levels in mouse xenograft tissue.

Methods

Cells were cultivated in the presence of trastuzumab or fulvestrant or both. Molecular events that resulted in an inhibition of cell proliferation and cell cycle progression or in an increased rate of apoptosis were studied. The distribution and abundance of the proteins p-Akt and p-Erk expressed in these cells in response to single agents or combinatorial treatment were also investigated. In addition, the effects of trastuzumab and fulvestrant, either as single agents or in combination on tumor growth as well as on expression of the protein p-MED1 expressed in in vivo mouse xenograft models was also examined.

Results

Cell proliferation was increasingly inhibited by trastuzumab or fulvestrant or both, with a CI<1 and DRI>1 in both human cell lines. The rate of apoptosis increased only in the BT-474 cell line and not in the ZR-75-1 cell line upon treatment with fulvestrant and not trastuzumab as a single agent (P<0.05). Interestingly, fulvestrant, in combination with trastuzumab, did not significantly alter the rate of apoptosis (in comparison with fulvestrant alone), in the BT-474 cell line (P>0.05). Cell accumulation in the G1 phase of cell cycle was investigated in all treatment groups (P<0.05), and the combination of trastuzumab and fulvestrant reversed the effects of fulvestrant alone on p-Akt and p-Erk protein expression levels. Using ZR-75-1 or BT-474 to generate in vivo tumor xenografts in BALB/c athymic mouse models, we showed that a combination of both drugs resulted in a stronger inhibition of tumor growth (P<0.05) and a greater decrease in the levels of activated MED1 (p-MED1) expressed in tumor issues compared with the use of either drug as a single agent.

Conclusions

We demonstrate that the administration of trastuzumab and fulvestrant in combination results in positive synergistic effects on both, ZR-75-1 and BT-474 cell lines. This combinatorial approach is likely to reduce physiological side effects of both drugs, thus providing a theoretical basis for the use of such combination treatment in order to resolve HR+/HER2+ triple positive breast cancer that has previously been shown to be resistant to endocrine treatment alone.

Elucidating the druggable interface of protein-protein interactions using fragment docking and coevolutionary analysis

Protein-protein interactions play a central role in cellular function. Improving the understanding of complex formation has many practical applications, including the rational design of new therapeutic agents and the mechanisms governing signal transduction networks. The generally large, flat, and relatively featureless binding sites of protein complexes pose many challenges for drug design. Fragment docking and direct coupling analysis are used in an integrated computational method to estimate druggable protein-protein interfaces. (i) This method explores the binding of fragment-sized molecular probes on the protein surface using a molecular docking-based screen. (ii) The energetically favorable binding sites of the probes, called hot spots, are spatially clustered to map out candidate binding sites on the protein surface. (iii) A coevolution-based interface interaction score is used to discriminate between different candidate binding sites, yielding potential interfacial targets for therapeutic drug design. This approach is validated for important, well-studied disease-related proteins with known pharmaceutical targets, and also identifies targets that have yet to be studied. Moreover, therapeutic agents are proposed by chemically connecting the fragments that are strongly bound to the hot spots.