Residual Pattern of Chlorantraniliprole, Thiamethoxam, Flubendiamide and Deltamethrin in Tomato Fruit and Soil

Tomato, Lycopersicon esculentum L. is grown widely as an important day-to-day demand vegetable. The crop is attacked by various polyphagous insect pests like tomato fruit borer, stink bug, cabbage looper, flea beetle, aphids, whitefly, two-spotted spider mite, etc., and oligophagous insects like leaf-miner, five-spotted hawkmoth, etc. To combat the damage and yield loss, various chemical insecticides were sprayed on tomatoes under field conditions. The residual pattern of insecticides like chlorantraniliprole, thiamethoxam, flubendiamide, and deltamethrin residues was studied following applications of chlorantraniliprole 18.5% SC (Coragen) @ 30 g a.i./ha, thiamethoxam 25% WG (Actara) @ 50 g a.i./ha, flubendiamide 39.35 M/M SC (Fame) @ 48 g a.i./ha and deltamethrin 2.8% EC (Decis 100) @ 12.5 g a.i./ha using Reverse Phase High-Performance Liquid Chromatography (RP-HPLC). Fruit samples were collected at 0 (1 h after application), 1, 2, 3, 5, 7 days and at harvest time. All the residues of insecticides such as chlorantraniliprole (0.09 mg kg- 1), thiamethoxam (0.03 mg kg- 1), flubendiamide (0.02 mg kg- 1), and deltamethrin (0.01 mg kg- 1) were persisted up to 5th day. There were no residues found at harvest time. The residues of chlorantraniliprole and deltamethrin persisted up to 3rd day of spraying whereas the residues of flubendiamide and thiamethoxam were not detected on the same day in the soil.

Assessment of prescribing pattern of drugs and completeness of prescriptions as per the World Health Organization prescribing indicators in various Indian tertiary care centers: A multicentric study by Rational Use of Medicines Centers-Indian Council of Medical Research network under National Virtual Centre Clinical Pharmacology activity

OBJECTIVE

The rational use of medicines as per the World Health Organization (WHO) should be practiced globally. However, data regarding the completeness of the prescriptions and their rational use is lacking from developing countries like India. Thus, the aim of this study was to assess the prescribing patterns of drugs and completeness of prescriptions as per WHO core drug use and complementary indicators to provide real-life examples for the Indian Council of Medical Research (ICMR) online prescribing skill course for medical graduates.

METHODS

Prescriptions of the patients, fulfilling inclusion criteria, attending Outpatient Departments of various specialties of tertiary care hospitals, were collected by thirteen ICMR Rational use of medicines centers located in tertiary care hospitals, throughout India. Prescriptions were evaluated for rational use of medicines according to the WHO guidelines and for appropriateness as per standard treatment guidelines using a common protocol approved by local Ethics committees.

RESULTS

Among 4838 prescriptions, an average of about three drugs (3.34) was prescribed to the patients per prescription. Polypharmacy was noted in 83.05% of prescriptions. Generic drugs were prescribed in 47.58% of the prescriptions. Further, antimicrobials were prescribed in 17.63% of the prescriptions and only 4.98% of prescriptions were with injectables. During the prescription evaluation, 38.65% of the prescriptions were incomplete due to multiple omissions such as dose, duration, and formulation.

CONCLUSION

Most of the parameters in the present study were out of the range of WHO-recommended prescribing indicators. Therefore, effective intervention program, like training, for the promotion of rational drug use practice was recommended to improve the prescribing pattern of drugs and the quality of prescriptions all over the country.

Energy and carbon budgeting of traditional land use change with groundnut based cropping system for environmental quality, resilient soil health and farmers income in eastern Indian Himalayas

Energy intensive traditional cereals based monoculture often lead to high greenhouse gas emissions and degradation of land and environmental quality. Present study aimed at evaluating the energy and carbon budget of diversified groundnut (Arachis hypogea L) based cropping system with over existing traditional practice towards the development of a sustainable production technology through restoration of soil and environmental quality and enhancement of farming resiliency by stabilizing farmers' income. The trials comprised of three introduced groundnut based systems viz. groundnut- pea (Pisum sativum), groundnut-lentil (Lens esculenta) and groundnut-toria (Brasssica campestris var. Toria) replacing three existing systems viz. maize (Zea mays L) - fallow, maize - toria, and rice (Oryza sativa L)-fallow systems. Four years study revealed that adoption of groundnut based systems reduced non-renewable energy input use (fertilizers, chemical, machinery and fossil fuels) by 25.5%, consequently that reduced the cost of production. Repeated analysis of variance measurement also affirmed that groundnut based systems (groundnut-pea>groundnut-lentil> groundnut-toria) increased the energy use efficiency, energy productivity, carbon use efficiency, net returns and decreased the specific energy and energy intensiveness. Groundnut based systems increased the mean system productivity and water productivity in terms of groundnut equivalent yield by 3.7 and 3.1 folds over existing practice. The savings of fossil fuel reduced greenhouse gas emissions owing to reduced use of farm machinery and synthetic fertilizers. Groundnut based systems significantly (p < 0.05) enhanced the soil carbon concentration (8.7-18.1%) and enzymatic activities (27.1-51.8%) over existing practice. Consequently, estimated soil quality index values were 35.9-77.3% higher under groundnut based systems than existing practice. Thus, the study indicated the resilient nature of groundnut based systems as an environmentally safe and sustainable production technology for enhancing resource use efficiency, reduce carbon emission, energy intensiveness and cost of production in the Eastern Himalaya region of India and similar ecosystems.

Synthesis of a novel, sequentially active-targeted drug delivery nanoplatform for breast cancer therapy

Breast cancer is the leading cause of cancer deaths among women. Paclitaxel (PTX), an important breast cancer medicine, exhibits reduced bioavailability and therapeutic index due to high hydrophobicity and indiscriminate cytotoxicity. PTX encapsulation in one-level active targeting overcomes such barriers, but enhances toxicity to normal tissues with cancer-similar expression profiles. This research attempted to overcome this challenge by increasing selectivity of cancer cell targeting while maintaining an ability to overcome traditional pharmacological barriers. Thus, a multi-core, multi-targeting construct for tumor specific delivery of PTX was fabricated with (i) an inner-core prodrug targeting the cancer-overexpressed cathepsin B through a cathepsin B-cleavable tetrapeptide that conjugates PTX to a poly(amidoamine) dendrimer, and (ii) the encapsulation of this prodrug (PGD) in an outer core of a RES-evading, folate receptor (FR)-targeting liposome. Compared to traditional FR-targeting PTX liposomes, this sequentially active-targeted dendrosome demonstrated better prodrug retention, an increased cytotoxicity to cancer cells (latter being true when FR and cathepsin B activities were both at moderate-to-high levels) and higher tumor reduction. This research may eventually evolve a product platform with reduced systemic toxicity inherent with traditional chemotherapy and localized toxicity inherent to single-target nanoplatforms, thereby allowing for better tolerance of higher therapeutic load in advanced disease states.

Design of a paclitaxel prodrug conjugate for active targeting of an enzyme upregulated in breast cancer cells

Breast cancer is the second most common cause of cancer-related deaths in women. Chemotherapy is an important treatment modality, and paclitaxel (PTX) is often the first-line therapy for its metastatic form. The two most notable limitations related to PTX-based treatment are the poor hydrophilicity of the drug and the systemic toxicity due to the drug's nonspecific and indiscriminate distribution among the tissues. The present work describes an approach to counter both challenges by designing a conjugate of PTX with a hydrophilic macromolecule that is coupled through a biocleavable linker, thereby allowing for active targeting to an enzyme significantly upregulated in cancer cells. The resultant strategy would allow for the release of the active ingredient preferentially at the site of action in related cancer cells and spare normal tissue. Thus, PTX was conjugated to the hydrophilic poly(amdioamine) [PAMAM] dendrimer through the cathepsin B-cleavable tetrapeptide Gly-Phe-Leu-Gly. The PTX prodrug conjugate (PGD) was compared to unbound PTX through in vitro evaluations against breast cancer cells and normal kidney cells as well as through in vivo evaluations using xenograft mice models. As compared to PTX, PGD demonstrated a higher cytotoxicity specific to cell lines with moderate-to-high cathepsin B activity; cells with comparatively lower cathepsin B activity demonstrated an inverse of this relationship. Regression analysis between the magnitude of PGD-induced cytotoxic increase over PTX and cathepsin B expression showed a strong, statistically significant correlation (r(2) = 0.652, p < 0.05). The PGD conjugate also demonstrated a markedly higher tumor reduction as compared to PTX treatment alone in MDA-MB-231 tumor xenograft models, with PGD-treated tumor volumes being 48% and 34% smaller than PTX-treated volumes at weeks 2 and 3 after treatment initiation.

Effects of a novel proteasome inhibitor BU-32 on multiple myeloma cells

Proteasome inhibition is associated with substantial antitumor effects in preclinical models of multiple myeloma (MM) as well as in patients. However, results of recent clinical trials to evaluate the effect of the proteasome inhibitor Bortezomib (Velcade(®), also called PS-341) in MM patients have shown limited activity when used as a single agent. This underscores the need to find new efficacious and less toxic proteasome inhibitors. Recently, carfilzomib was approved for the treatment of refractory/relapsed MM and several new agents have been introduced into the clinic, including marizomib and MLN9708, and trials investigating these second-generation proteasome inhibitors have demonstrated promising results. We have recently synthesized a novel proteasome inhibitor, BU-32, and tested its growth inhibitory effects in different human MM cells including RPMI8226, MM.1S, MM.1R, and U266. In this study, we evaluate the efficacy of the novel proteasome inhibitor BU-32 (NSC D750499) using an in vitro MM model. BU-32 exhibits strong cytotoxicity in a panel of MM cell lines--RPMI8226, MM1S, MM1R, and U266. In addition, we demonstrate by proteasome inhibition assay that BU-32 potently inhibits the chymotryptic- and caspase-like activities of the 26S proteasome. We further show from Annexin V-FITC binding studies that BU-32, like Bortezomib, induces apoptosis in a panel of MM cell lines but the effect is more pronounced with BU-32-treated cells. Invasion assay with the MM.1S cell line indicates that BU-32 inhibits the invasiveness of myeloma cells. Results from our studies using real-time PCR array analyses show that BU-32 effectively downregulates an array of angiogenesis and inflammatory markers. Our results suggest that BU-32 might be a potential chemotherapeutic agent with promising antitumor activity for the treatment of MM.

Design, synthesis, and biological evaluation of bone-targeted proteasome inhibitors for multiple myeloma

Multiple myeloma (MM) is an incurable neoplasm characterized by devastating and progressive bone destruction. Standard chemotherapeutic agents have not been effective at significantly prolonging the survival of MM patients and these agents are typically associated with often severe, dose-limiting side effects. There is great need for methods to target the delivery of novel, effective cytotoxic agents specifically to bone, where myeloma cells reside. We have synthesized and evaluated the effects of the bone-targeted proteasome inhibitors PS-341-BP-1, PS-341-BP-2 and MG-262-BP on cell proliferation using the mouse 5TGM1 and human RPMI 8226 cell lines in vitro. The compounds exhibit strong cytotoxicity on MM cell lines and reduce the number of viable cells in a dose dependent manner.

Abstract PD09-07: Therapeutic potential of targeting ATM-PELP1-p53 axis in triple negative breast cancer

Triple negative breast cancer (TNBC) comprises approximately 15% of all breast cancers, lacks expression of ER, PR, and HER2 and is clinically aggressive with shorter disease free survival. TNBC patients do not benefit from antiestrogen and herceptin-based therapies. Evolving evidence suggests that overexpression of mutant p53 is significantly associated with TNBC progression. DNA damage response (DDR) is critical for the maintenance of genome stability and serves as an anti-cancer barrier during tumorigenesis. However, the role of DDR in tumor progression and metastasis is less known. Recent studies suggest that the ATM kinase is hyperactive in late stage breast tumor tissues with lymph node metastasis. Our ongoing studies have identified proline, glutamic acid, leucine rich protein 1 (PELP1), a proto-oncogene overexpressed in breast cancer, as a novel substrate of ATM. The objective of this study is to determine the mechanism and significance of ATM mediated phosphorylation of PELP1 and its crosstalk with the p53 pathway in TNBC cells. To test this we have used three ER-negative mutant p53 breast cancer cell lines (MDA-MB-231, MDA-MB-468, BT20), with ER-positive (ZR-75 and MCF7) cell lines as controls. Using PELP1 specific shRNAs, we generated model cells that have stable expression of either control or PELP1 shRNA. Our results with PELP1 knockdown models indicate that PELP1 promotes stability of p53 and functions as a co-regulator of p53. PELP1 has the potential to modulate CBP/p300 mediated acetylation of the Lysine 382 residue of p53. Immunoprecipitation and chromatin immunoprecipitation (ChIP) assays were performed to examine PELP1 interaction with p53 and its recruitment to p53 target genes respectively. ChIP assays revealed that PELP1 knockdown significantly reduces the recruitment of p53 to the target genes. The p53 regulatory role of PELP1 is mediated by the phosphorylation of PELP1 at the conserved SQ motif by ATM. We generated model cells that overexpress WT or mutant (S1033A) PELP1 and demonstrated the significance of ATM mediated phosphorylation in PELP1 mediated p53 co-activation functions. Based on the sequence of the site of phosphorylation, we have developed a novel cell permeable peptide (TAT-1033PELP1 inhibitor) as well as a phospho-PELP1 antibody that uniquely recognizes S1033 phosphorylated PELP1. We confirmed ATM mediated phosphorylation of PELP1 in vivo using phospho PELP1 antibody (1033p-PELP1). The TAT 1033 inhibitor peptide significantly reduced ATM mediated phosphorylation of endogenous PELP1. Treatment of ER− positive breast cancer cells with this peptide resulted in resistance to genotoxic stress compared to cells that are treated with control TAT peptide. However, in TNBC cells that has a mutant p53, PELP1 knockdown or treatment with TAT-PELP1 inhibitor resulted in significant loss of cell viability and increase in apoptosis in response to genotoxic stress. IHC analysis of tumor tissue array (n = 100) revealed increased PELP1 phosphorylation in advanced ER-negative tumors and its status correlated with ATM. Collectively, our results suggest that hyperactive ATM-PELP1-p53 pathway contributes to TNBC progression and that the TAT-1033PELP1 inhibitor represents a novel therapeutic to block PELP1 oncogenic functions in TNBC.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD09-07.

Abstract P5-04-04: Significance of PELP1/HDAC2/microRNA-200 regulatory network in EMT and metastasis of breast cancer

Tumor metastasis remains a significant clinical problem and is the leading cause of death among breast cancer patients. Estrogen receptor (ER)-coregulators play an essential role in cancer progression and metastatic tumors express increased levels of coregulators. Proline glutamic acid rich protein (PELP1) is an ER coregulator, its expression is upregulated during breast cancer progression to metastasis and is an independent prognostic predictor of shorter survival of breast cancer patients. MicroRNA (miR) mediated regulation of tumorigenesis is emerging as a new paradigm in cancer biology and widespread misexpression of miRs has been reported in breast cancer. The objective of this study is to examine the mechanism and therapeutic significance of PELP1 regulation of miRs leading to breast cancer metastasis. We have used both ER+ve (ZR75, MCF7) and ER-ve (MDAMB231, MDAMB468) models that either stably overexpress PELP1 or PELP1shRNA. Boyden chamber, and invasion assays demonstrated that PELP1 down regulation significantly affect migration of both ER+ve and ER-ve cells. Epithelial to Mesenchymal Transition (EMT) real time qPCR Array studies identified PELP1 modulate expression of EMT genes Snail, Twist, ZEB1, ZEB2, Vimentin and MMPs. Importantly, whole genome microRNA array analysis using PELP1 model cells revealed that miR200a and miR141 were significantly upregulated in cells expressing PELP1-shRNA compared to control cells. Accordingly, over expression of PELP1 in low metastatic model cells decreased expression of miR200a and miR141. PELP1 regulation of miRs was further confirmed by ZEB1 and ZEB2 3′ UTR luciferase reporter assays. ChIP analysis revealed recruitment of PELP1 to the proximal promoter region of miR-200a and miR141 and promoter reporter assays further confirmed PELP1 regulation of miRs. Interestingly, PELP1 down regulated expression of miR200a and miR141 by promoting repressive chromatin modifications via HDAC2. Supporting this, HDAC inhibitors reversed PELP1 driven repressive effects. Further, ectopic expression of miR200a and miR141 mimetic decreased PELP1 mediated invasion/metastatic functions. Prognostic significance of PELP1-miRNA axis was determined using Tissue micro-array (TMA) and in situ hybridization (ISH assays) of Locked Nucleic Acid (LNA™)-based microarray approach in 102 human breast tumors. To test therapeutic potential in vivo, we have generated ZR-PELP1- and MCF7-PELP1-shMIMIC of miR200a and miR141 stable cells. In vitro gene expression and Boyden chamber assays using these model cells revealed that shMIMIC of miR200a and miR141 reversed PELP1 mediated alterations in gene expression and reduced PELP1 driven migration/invasion. Proof of principle studies using IVIS imaging of nude mice based assays of GFP-Luc labeled cells demonstrated therapeutic efficacy of miRIDIAN shMIMIC of miR200a and miR141 on PELP1 driven in vivo metastasis. Collectively, these novel findings demonstrate for the first time a previously unknown role for PELP1 in epigenetically controlling the functions of tumor metastasis suppressor miR-200a and miR141. These results suggest that PELP1-miR axis may be crucial stimulus for promoting EMT and breast cancer metastasis. This study is funded by NIH T32CA148724 Postdoc Fellowship Grant.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-04-04.

Abstract P6-04-07: Significance and therapeutic potential of PELP1-mTOR axis in breast cancer progression and therapy resistance

Proline, Glutamic-acid and Leucine-rich Protein 1 (PELP1) is a proto-oncogene that modulates ER signaling by functioning as an ER-coregulator. Emerging studies demonstrated that in a subset of breast tumors, PELP1 is predominantly localized in the cytoplasm and that PELP1 participates in extranuclear signaling by facilitating ER interactions with Src, PI3K, and AKT. PELP1 expression is upregulated in breast cancer, its deregulation contributes to therapy resistance, and PELP1 is a prognostic marker of poor survival. However, the mechanism by which PELP1 extranuclear actions contributes to cancer progression and therapy resistance remains unknown. We have recently discovered that PELP1 has the potential to interact with mammalian target of rapamycin (mTOR), a serine/threonine kinase that forms two distinct complexes called mTORC1 (containing Raptor and PRAS40) and mTORC2 (containing Rictor and Protor). The objective of this application is to test whether crosstalk occurs between mTOR and PELP1 signaling axis and to test whether mTOR targeting drugs can be used to target PELP1 oncogenic functions. We have used breast cancer cells with PELP1 overexpression (MCF7-PELP1, ZR75-PELP1, T47D-PELP1) or PELP1 down regulation (MCF7-PELP1shRNA, ZR75-PELP1shRNA) along with controls to study the role of PELP1 in the regulation of mTOR axis. PELP1 knockdown significantly reduced downstream mTOR signaling components as analyzed by Western analysis using phospho-S6K, -4EBP1, -mTOR and -Akt, antibodies. Overexpression of PELP1 activated mTOR signaling components. Using immunoprecipitation, we have demonstrated that PELP1 interacts with mTOR. Further immunopreciptation analysis using Rictor and Raptor specific antibodies revealed that PELP1 associates with both TORC1 and TORC2 complexes. Using PELP1WT and PELP1cyto (that predominantly localizes in the cytoplasm), we have demonstrated the differential activation of mTOR signaling components: PELP1WT activated both TORC1 and TORC2 pathways, while PELP1cyto uniquely activated TORC2. mTOR targeting drugs (Rapamycin or AZD8055) showed a significant effect on the in vitro proliferation of PELP1 model cells. AZD8055 is more potent in reducing PELP1 driven tumor growth in vivo compared to rapamycin. Immunohistochemical studies on xenografts derived from MCF7, MCF7-PELP1WT and MCF7-PELP1cyto models demonstrated that PELP1 signaling modulates mTOR signaling in vivo and inhibition of mTOR signaling rendered PELP1 driven tumors to be highly sensitive to therapeutic inhibition. Further, mTOR inhibitors sensitized tamoxifen therapy resistant PELP1cyto model cells to hormonal therapy. IHC analysis of mammary glands and mammary tumors from PELP1Tg mice revealed deregulation of mTOR signaling components with excessive activation of S6K and 4EBP1. Using breast tumor tissue arrays (n = 100), we found significant correlation of PELP1 cytosolic localization with mTOR signaling. Collectively, the experimental results from these studies identified PELP1-mTOR axis as a novel component of PELP1 oncogenic functions and suggests, mTOR inhibitor(s) will be effective chemotherapeutic agents for down regulating PELP1 oncogenic functions and for blocking PELP1-mediated therapy resistance.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-04-07.

Interobserver variability in retreatment decisions of recurrent and residual aneurysms

BACKGROUND AND PURPOSE

The degree of variation in retreatment decisions for residual or recurrent aneurysms among endovascular therapists remains poorly defined. We performed a multireader study to determine what reader and patient variables contribute to this variation.

MATERIALS AND METHODS

Seven endovascular therapists (4 neuroradiologists, 3 neurosurgeons) independently reviewed 66 cases of patients treated with endovascular coil embolization for ruptured or unruptured aneurysm. Cases were rated on a 5-point scale recommending for whether to retreat and a recommended retreatment type. Reader agreement was assessed by intraclass correlation coefficient and by identifying cases with a "clinically meaningful difference" (a difference in score that would result in a difference in treatment). Variables that affect reader agreement and retreatment decisions were examined by using the Wilcoxon signed-rank test, Pearson χ(2) test, and linear regression.

RESULTS

Overall interobserver variability for decision to retreat was moderate (ICC = 0.50; 95% CI, 0.40-0.61). Clinically meaningful differences between at least 2 readers were present in 61% of cases and were significantly more common among neuroradiologists than neurosurgeons (P = .0007). Neurosurgeons were more likely to recommend "definitely retreat" than neuroradiologists (P < .0001). Previously ruptured aneurysms, larger remnant size, and younger patients were associated with more retreat recommendations. Interobserver variability regarding retreatment type was fair overall 0.25 (95% CI, 0.14-0.41) but poor for experienced readers 0.14 (95% CI, 0-0.34).

CONCLUSIONS

There is a large amount of interobserver variability regarding the decision to retreat an aneurysm and the type of retreatment. This variability must be reduced to increase consistency in these subjective outcome measurements.

Comparative in vitro cytotoxicity study of carbon nanotubes and titania nanostructures on human lung epithelial cells

The aim of this study is to assess in vitro cytotoxic effects of titania nanostructures and carbon nanotubes (CNTs) by exposing A549 lung epithelial cell line to these materials. Titania nanotubes (TiNTs) were grown by hydrothermal treatment of TiO(2) nanoparticles, followed by annealing them at 400°C. The titania nanostructures obtained on annealing (mixture of nanotubes and nanorods) were hollow and open ended, containing 3-5 layers of titania sheets, with an internal diameter ∼3-5 nm and external diameter ∼8-10 nm, and a specific surface area of 265 m(2)/g. As-supplied single walled (SWCNTs) and microwave plasma enhanced chemical vapour deposition (MPCVD) grown multi walled carbon nanotubes (MWCNTs) were used in this study. The lengths and diameters of the SWCNTs were 5-10nm and 0.5-3 nm respectively. The lengths and diameters of the MWCNTs were 25-30 μm and 10-30 nm respectively. The cell viability was evaluated using the MTT (3-(4,-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium) assay. No significant cytotoxic effects of titania nanostructures were observed over a period of a week of testing time, while the presence of CNTs in some cases demonstrated significant cytotoxic effects. Finally, possible reason of cytotoxicity is discussed in the light of microstructures of materials.

Thinning of multilayer graphene to monolayer graphene in a plasma environment

We present a facile approach to transform multilayer graphene to single-layer graphene in a gradual thinning process. Our technique is based upon gradual etching of multilayer graphene in a hydrogen and nitrogen plasma environment. High resolution transmission microscopy, selected area electron diffraction and Raman spectroscopy confirm the transformation of multilayer graphene to monolayer graphene at a substrate temperature of ∼ 400 °C. The shift in the position of the G-band peak shows a perfect linear dependence with substrate temperature, which indicates a controlled gradual etching process. Selected area electron diffraction also confirmed the removal of functional groups from the graphene surface due to the plasma treatment. We also show that plasma treatment can be used to engineer graphene nanomesh structures.

Abstract P4-06-01: Significance and Therapeutic Potential of PELP1 in ER-Negative Breast Cancers

Background: During the past 20 years, studies have extensively focused on the role of estrogen receptor (ER) and progesterone receptor (PR) in breast cancer. Even through ER and PR explain the biology of ER-positive tumors, it remain unknown as to what drives ER-negative metastatic tumors. Recent advances implicated potential importance of several additional nuclear receptor (NRs) including ERRα, AR, GR, and PPAR in breast cancer. NR action is complex, requires functional interactions with coregulators, and deregulation of coregulators occur during cancer progression. As a modulator of multiple NR functions, coregulators are likely to play a role in breast cancer progression to metastasis. Recent studies indicated that metastatic tumors have increased expression of corgulators. Proline glutamic acid rich protein (PELP1) is a NR coregulator, and its expression is upregulated during breast cancer progression. The objective of this study is to examine whether proto-oncogene PELP1 contributes to metastatic potential of ER-negative breast cancer cells and to test whether blocking of PELP1 signaling axis will have therapeutic effect.

Methods: We have used two ER-negative model cells; (1) MDA-MB231 cells that facilitate study of bone and lungs metastasis of breast cancer cells using Nude mice models, (2) 4T1 cells, a clinically relevant model of spontaneous breast cancer metastasis that facilitate tumor growth studies using syngenic mice. To establish the significance of PELP1 axis, we have established clones stably expressing PELP1-shRNA (MDA-MB231- PELP1 shRNA, 4T1-PELP1 shRNA). Proliferation was measured using CellTiter-Glo assays. Role of PELP1 on metastasis was studied using Boyden chamber, wound healing, invasion and MMP assays. Epithelial to Mesenchymal Transition (EMT) real time qPCR Array (Super array) was used to identify PELP1 target genes and targets were validated using ChIP assays. Nude mice based assays were performed to study the role of PELP1 on in vivo metastasis.

Results: MDA-MB231 and 4T1 cells expressing PELP1-shRNA showed decreased PELP1 expression (∼75% of endogenous levels) and exhibited decreased propensity to proliferate in in vitro growth assays. Boyden chamber and wound healing assays showed PELP1 down regulation substantially affect migratory potential of MDA-MB231 and 4T1 cells. PELP1 shRNA model cells showed alterations in the expression of the EMT markers. EMT array studies identified eight genes involved in the EMT (including MMPs, E-cadherin, MTA1) as PELP1 potential target genes and ChIP studies showed PELP1 recruitment to these gene promoters. Overexpression of PELP1 in nonmetastatic cells increases their propensity for metastasis in vivo, while, PELP1 knockdown in metastatic model cells decreased their metastatic potential. Nanopartiles delivering PELP1-siRNA significantly affected the growth and metastatic potential of ER-ve cells.

Conclusions: These results suggest that PELP1 play a role in ER-ve breast cancer metastasis by promoting cell motility and EMTand blockage of PELP1 axis reduces metastasis potential of ER-negative breast cancer cells. Understanding how NR coregulator PELP1play a role in metastasis will be useful in maximizing treatment opportunities for metastatic breast cancer. This study is funded by Komen grant KG091267.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-06-01.

Functionalized graphene and graphene oxide solution via polyacrylate coating

Water soluble graphene with various chemical- and biofunctionalities is essential for their different applications. However, exfoliated graphenes are insoluble in water and water soluble graphene oxide precipitate if they are chemically reduced to graphene. We have developed a polyacrylate coating method for graphene oxide and then chemically reduced it into graphene. We found that polyacrylate coating can improve the colloidal stability of both graphene and graphene oxide. The coated graphene has been characterized using XPS, FTIR, XRD and micro-Raman spectroscopy. The primary amine present on the coating backbone has been used to derive glucose functionalized water soluble graphene. Various other functional graphenes can be anticipated from the polyacrylate coated graphene.

BU-32: a novel proteasome inhibitor for breast cancer

Introduction

Proteasome inhibition provides an attractive approach to cancer therapy and may have application in the treatment of breast cancer. However, results of recent clinical trials to evaluate the effect of the proteasome inhibitor Bortezomib (Velcade^®, also called PS-341) in metastatic breast cancer patients have shown limited activity when used as a single agent. This underscores the need to find new and more efficacious proteasome inhibitors. In this study, we evaluate the efficacy of the novel proteasome inhibitor BU-32 (NSC D750499-S) using in vitro and in vivo breast cancer models.

Methods

We have recently synthesized a novel proteasome inhibitor (BU-32) and tested its growth inhibitory effects in different breast cancer cells including MCF-7, MDA-MB-231, and SKBR3 by in vitro cytotoxicity and proteasomal inhibition assays. The apoptotic potential of BU32 was tested using flow cytometry and analyzing cell cycle regulatory proteins. In vivo tumor xenograft studies for solid tumor as well as tumor metastasis were conducted using MDA-MB-231-GFP cells.

Results

We report for the first time that BU-32 exhibits strong cytotoxicity in a panel of cell lines: MDA-MB-231 (IC₅₀ = 5.8 nM), SKBR3 (IC₅₀ = 5.7 nM) and MCF-7 cells (IC₅₀ = 5.8 nM). It downregulates a wide array of angiogenic marker genes and upregulates apoptotic markers, including Bid and Bax. Incubation of MDA-MB-231 cells with BU-32 results in the accumulation of cell cycle inhibitor proteins p21 and p27 and stabilization of the tumor suppressor protein p53. Studies in in vivo solid tumor and metastasis models show significant effect with a 0.06 mg/kg dose of BU-32 and marked reduction in tumor burden in the skeleton.

Conclusions

We have shown that BU-32 is effective in cultured breast cancer cells and in breast cancer xenografts. The results suggest its potential benefit in breast cancer treatment.

Transferring vertically aligned carbon nanotubes onto a polymeric substrate using a hot embossing technique for microfluidic applications

We explored the hot embossing method for transferring vertically aligned carbon nanotubes (CNTs) into microfluidic channels, fabricated on poly-methyl-methacrylate (PMMA). Patterned and unpatterned CNTs were synthesized by microwave plasma-enhanced chemical vapour deposition on silicon to work as a stamp. For hot embossing, 115 degrees C and 1 kN force for 2 min were found to be the most suitable parameters for the complete transfer of aligned CNTs on the PMMA microchannel. Raman and SEM studies were used to analyse the microstructure of CNTs before and after hot embossing. The PMMA microparticles with dimensions (approx. 10 microm in diameter) similar to red blood cells were successfully filtered using laminar flow through these microfluidic channels. Finally, a microfluidic-based point-of-care device for blood filtration and detection of bio-molecules is drawn schematically.

Effect of Mg(2+) ion in protein secretion by magnesium-resistant strains of Pseudomonas aeruginosa and Vibrio parahaemolyticus isolated from the coastal water of Haldia port

A rapidly growing industrial complex including oil refineries and chemical industries has developed around the coastal area of Haldia port in the district of Midnapore, West Bengal, India. The coastal water is highly polluted with industrial wastes along with petroleum hydrocarbons. The bacteria isolated from the different sites of the coastal waters were Escherichia coli, Alcaligenes, Acinetobacter, Klebsiella spp., Micrococcus spp., Vibrio spp., Pseudomonas aeruginosa and Vibrio parahaemolyticus. The salinity of the water during the time of collection of samples around the port area was 8. 2 ppt. Among the isolated organisms, only two isolates, P. aeruginosa and V. parahaemolyticus, showed growth at 300 mM Mg(2+) ion concentration. However, a 3 mM Mg(2+) concentration was detected in the coastal water whereas other metal ion concentrations were less than 3x10(-5) mM. Resistance to Mg(2+) (300 mM) was determined by a 5.5-kb plasmid. A large amount of a 40-kDa outer membrane protein, which was highly soluble in 1 M MgCl(2), was isolated from both V. parahaemolyticus and P. aeruginosa. The secretion of proteins in the culture supernatant of V. parahaemolyticus was highly increased when the cells were grown in the presence of 300 mM Mg(2+), whereas very low secretion was observed in the same concentration of Mg(2+) in the case of P. aeruginosa. Mg(2+) may act as a specific release factor in protein secretion by V. parahaemolyticus strains.

Endothelium-dependent contractile actions of proteinase-activated receptor-2-activating peptides in human umbilical vein: release of a contracting factor via a novel receptor

The contractile actions of the proteinase-activated receptor-2-activating peptides (PAR2APs), SLIGRL-NH2 (SL-NH2), SLIGKV-NH2 (KV-NH2), trans-cinnamoyl-LIGRLO-NH2 (tc-NH2), and the PAR1-AP. TFLLR-NH2 (TF-NH2) as well as trypsin and thrombin were studied in endothelium-denuded and intact human umbilical vein (HUV) ring preparations. In HUV rings with, but not without an intact endothelium, PAR2APs caused a concentration-dependent contractile response, whereas LSIGRL-NH2 trypsin and PAR1APs were inactive. The contractile response was not affected by the endothelin ETA receptor antagonist, BQ123, the cyclooxygenase inhibitor, indomethacin, the leukotriene synthesis inhibitor, MK886, or the epoxygenase/P450 inhibitor, SKF-525A. Other pharmacological antagonists (prazosin, Losartan") were similarly inactive. The order of potencies of the PAR2APs to cause a contraction in the endothelium-intact preparation was: SL-NH2 > > KV-NH2 > or = tc-NH2. Using an endothelium-free rat aorta ring as a reporter tissue, surrounded with endothelium-intact HUV as a donor tissue in a 'sandwich assay,' we also monitored the ability of SL-NH2, TF-NH2, trypsin and thrombin to release either contractile (EDCF) or relaxant (EDRF) factors. In the 'sandwich assay' done in the presence of L-NAME (0.1 mM), the endothelium-intact HUV tissue (but not endothelium-denuded HUV) released a contractile factor (EDCF) in response to SL-NH2 (50 microM) but not to trypsin or LSIGRL-NH2. The SL-NH2-mediated release/action of the EDCF was not affected by BQ123, indomethacin, MK886 or SKF-525A. In the 'sandwich assay', trypsin (4-10 nM), SL-NH2, KV-NH2 and tc-NH2 caused the release of a relaxant activity (EDRF) from the endothelium-intact (but not the denuded) HUV preparation. The release of EDRF was blocked by 0.1 mM (omega)nitro-L-arginine-methylester (L-NAME). Neither thrombin (10 u ml(-1), 100 nM) nor TF-NH2 (50 microM) were active in this EDRF-release assay. The relative potencies of the PAR2 agonists for causing the release of EDRF in the HUV sandwich assay were: trypsin> >SL-NH2> >tc-NH2>KV-NH2. This order of potencies differed from the one observed for the same agonists in the HUV contraction assay (above) and in an intracellular calcium signalling assay, conducted with cloned human PAR2 that was expressed in cultured rat kidney KNRK cells: trypsin > > SL-NH2 = tc-NH2 > KV-NH2. We conclude that PAR2APs (but not PAR1APs) via a receptor distinct from PAR2, can cause a contractile response in endothelium-intact HUV tissue via the release of a diffusable EDCF, that is different from previously recognized smooth muscle agonists (e.g. prostanoid metabolites, endothelin, noradrenaline, angiotensin-II, acetylcholine).

Dual endothelium-dependent vascular activities of proteinase-activated receptor-2-activating peptides: evidence for receptor heterogeneity

1. The vascular actions of the proteinase-activated receptor-2-activating peptides (PAR2APs), SLIGRL-NH2 (SL-NH2) and SLIGKV-NH2 (KV-NH2) as well as the reverse-sequence peptide, LSIGRL-NH2 (LS-NH2) and an N-acylated PAR2AP derivative, trans-cinnamoyl-LIGRLO-NH2 (tcLI-NH2), were studied in rat intact and endothelium-denuded artery ring preparations, primarily from the pulmonary artery (RPA). 2. In RPA rings with but not without a functional endothelium, SL-NH2 (but not LS-NH2) caused either an endothelium-dependent relaxation (at concentrations: < 10 microM) or (at higher concentrations: > 10 microM), an endothelium-dependent contraction. No contractile response was observed in endothelium-denuded preparations, that otherwise contracted in response to the PAR1AP, TFLLR-NH2. 3. The endothelium-dependent contractile response to SL-NH2 was not blocked by the alpha-adrenoceptor antagonist prazosin, the endothelin antagonist BQ123, the angiotensin II antagonist DuP753, by tetrodotoxin; nor by the enzyme inhibitors, N(omega)-nitro-L-arginine-methylester (NO-synthase), indomethacin (cyclo-oxygenase), SKF-525A (epoxygenase) and MK886 (leukotriene synthesis inhibitor). 4. In the relaxation assay, KV-NH2 was 5 fold less potent than SL-NH2, whereas in the contractile assay KV-NH2 was about equipotent with SL-NH2. However, the maximal contractile response to KV-NH2 was lower than that of SL-NH2. 5. The PAR2AP analogue, tcLI-NH2, was as active as SL-NH2 in the relaxation assay but was inactive as a contractile agonist in the endothelium-intact RPA. 6. The relaxant responses caused by SL-NH2 and trypsin, as well as the contractile response caused by SL-NH2, did not desensitize in the course of repeated exposures of the tissue to agonist; whereas the contractile response to trypsin, only observed at concentrations greater than 30 u ml(-1), was desensitized by previous exposure of the tissue to either thrombin or trypsin. 7. In a contractile assay, where the tissue was desensitized to a concentration of trypsin that would otherwise cause a relaxant response, the preparation still contracted in response to SL-NH2. However, the trypsin-desensitized preparations were no longer contracted by thrombin. 8. From the cross-desensitization by thrombin of the contractile response to trypsin (and vice versa), we concluded that the contractile effect of trypsin was due to activation of the thrombin receptor and not PAR2. 9. We concluded that the endothelium-dependent contraction caused by high concentrations of SL-NH2 is due to an as yet unidentified contracting factor; whereas the endothelium-dependent relaxation response observed at low concentrations of SL-NH2 (< or = 10 microM) is mediated by nitric oxide. 10. The distinct structure activity profiles for the contractile response (potency of KV-NH2 < or = SL-NH2) compared with the relaxant response (potency of KV-NH2 << SL-NH2); the contractile responsiveness to SL-NH2 of an endothelium-intact RPA preparation, that did not contract in response to trypsin; and the lack of contractile activity of the PAR2AP analogue tcLI-NH2, that was as active as SL-NH2 in the relaxation assay all argue in favour of receptor heterogeneity in the vasculature for the PAR2APs. It remains to be determined if the distinct endothelial receptor responsible for the contractile action of SL-NH2 can be proteolytically activated, like PAR1 and PAR2.

Serum lipids and coronary heart disease in British elderly

To assess the relationship between serum lipids and coronary heart disease (CHD) in an elderly population (mean age = 77.4; SEM +/- 0.4; range 70-92 years), serum total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were measured in 84 (males = 52) subjects with evidence of definite myocardial infarction and 125 (males = 77) age- and sex-matched controls free of CHD on Rose questionnaire and resting electrocardiogram. On multivariate logistic regression analysis, CHD showed inverse association with HDL-C (odds ratio for decrease by 1 s.d. = 1.6, P = 0.02) in males and positive association with TC (odds ratio for increase by 1 s.d. = 1.8, P = 0.03) and LDL-C (odds ratio for increase by 1 s.d. = 1.8, P = 0.04) in females. Of the other variables only diabetes in males (odds ratio 2.4, P = 0.05) and left ventricular hypertrophy in females (odds ratio 8.8, P = 0.03) were associated with CHD. The results suggest that further prospective studies to further evaluate the relation of serum lipids with CHD in this age group are indicated.

Adverse drug reactions: an investigation on an acute geriatric ward

A total of 521 patients consecutively admitted to an acute geriatric unit were kept under surveillance by one observer during their stay. All drugs given to them and the occurrence of adverse events were recorded. One hundred and seventeen adverse drug reactions occurred in 94 patients representing 18.8% of the 500 patients receiving drugs. Thirteen of these reactions were considered severe. Each patient received an average of 6.1 drugs, not necessarily simultaneously. Altogether 212 different drug preparations were used. Diamorphine and insulin had the highest adverse reaction rates, diamorphine having the highest risk of a severe adverse reaction. Antibiotics and diuretics caused the most adverse reactions, and were by far the most commonly prescribed drugs (26.5% of the sample). Of the patients receiving eight or more drugs, 41% suffered an adverse drug reaction.

Advanced abdominal pregnancy

Two cases of advanced abdominal pregnancy have been reviewed and two live babies have been delivered. Emphasis has been given to suggestive clinical features which may help in the pre-operative diagnosis of this rare condition.