A simple and sensitive gas chromatography method for determination of isosorbide dinitrate and its metabolites in human plasma: application to pharmacokinetics study on oral spray

A sensitive method for the simultaneous determination of isosorbide dinitrate (ISDN) and its mononitrate metabolites, isosorbide 2-mononitrate and isosorbide 5-mononitrate (IS-2-MN and IS-5-MN), in human plasma was developed using capillary gas chromatography with electron-capture detection, whereas 1,2,4-butanetriol trinitrate was used as internal standard. The analytes were extracted with a simple liquid-liquid extraction from plasma and separated on a DB-1 column. The results of method validation demonstrated that the calibration curves were linear in range of 2-60 ng/mL for ISDN and IS-5-MN, 1-20 ng/mL for IS-2-MN, respectively. The precision (RSD%) was less than 15%, and the lower limit of quantitation was identifiable and reproducible at 2 ng/mL for ISDN and IS-5-MN, 1 ng/mL for IS-2-MN. The analytes in plasma were stable after being stored for more than 30 days and after 2 freeze-thaw cycles (-20 to 25°C). And then this method was successfully applied to a pharmacokinetic investigation on isosorbide dinitrate oral spray in healthy volunteers.

Abstract P6-06-50: Obesity and the influence on tumor biology as determined by the intermediate risk 21-gene recurrence scores (RS) and the 70-gene breast cancer recurrence signature (70-GS) assay

BACKGROUND

Obesity is an apparent risk factor for postmenopausal breast cancer (BC), estrogen receptor (ER) positive BC, larger tumors, lymph node (LN) involvement, as well as recurrence of BC and BC death despite treatment. However, the specific mechanism of these increased risks remains unclear. Our prior work described the negative influence of metabolic syndrome on BC recurrence in patients assessed by a 21 gene recurrence score (RS) in the low risk and intermediate risk tertiles (Lakhani et al PSABCS 2012). The objective of this study was to analyze the interaction of obesity and BC biology in patients assessed by the 70 gene signature (70-GS) for BC recurrence and the 80 gene molecular subtyping.

METHODS

We studied consecutive patients with newly diagnosed ER positive, LN negative BC treated at Loyola University Medical Center between 2005 -2012 who had an intermediate RS. The 70-GS was done on these same paraffin-embedded tumor blocks for risk level and molecular subtype. Standard descriptive statistics are reported. Wilcoxon rank sum tests were performed for the comparison of BMI by groups defined by RS scores (≤24 vs ≥25) and the 70 gene signature assay (high risk vs low risk). In addition, Chi-squared test, or Fisher's exact test as appropriate, was used to examine the association between BMI tertiles and the 70GS or molecular subtype.

RESULTS

From 102 patients with intermediate RS, the 70-GS was successful in 89 samples. The average age was 61 years (range 41-79). The median body mass index (BMI) was 29 (range 18-53). There was a significant association between BMI and RS (p = 0.0110): median BMI = 28 in patients with RS ≤24; median BMI 33 in patients with RS ≥25. There was a significant association between BMI and the 70-GS (p = 0.0116). Median BMI 27 in low risk group; median BMI 32 in high risk group. There was a significant association between the 70-GS and BMI (p = 0.0190).

Association between the 70-GS and BMI70-GS RiskHealthy (18-25)Overweight (26-30)Obese (>30)TotalHigh (n pts)1292950Low (n pts)15131139

There was a significant association between molecular subtype and BMI tertiles (p = 0.0803).

Association between molecular subtype and BMI tertiles HealthyOverweightObeseTotalLuminal A (n pts)14131239Luminal B (n pts)1392648

CONCLUSION

There is a striking interaction of obesity and BC biology as defined by the RS and 70-GS assays. Our data suggest that BC in obese women may have more aggressive tumor biology and higher risk of recurrence than BC in those with a low BMI. Further molecular characterization of the BC from obese patients may elucidate the role obesity plays in BC development and progression, as well as provide rationale for targeted therapeutic trials. Clinical trials targeting known carcinogenic pathways related to obesity (such as metformin and statins) are ongoing. Several genes in the 70-GS are the same genes expressed in obese patients. Additional studies examining the prognostic and predictive value of the 70-GS need to be conducted for this patient population.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-50.

Comparative genomic hybridization in a case of melanoma that loses expression of S100, HMB45, Melan A and tyrosinase in metastasis

We recently reported three cases of metastatic melanoma that does not express S100, HMB45, Melan A and Tyrosinase. A concurrent cutaneous scalp primary melanoma was identified later in one of the cases, which showed strong expression of these markers. The difference in immunophenotype between the primary melanoma and its metastasis in the parotid gland in this case raised the question of the biological significance of the expression of these markers and metastatic potential. To address this question, we utilized microarray comparative genomic hybridization (aCGH) to compare the cytogenetic features between the primary and metastatic melanoma. We observed chromosomal gains including 6p, entire chromosome 7, and 8q11.1-q24.3 in both primary and metastatic tumors. However, the metastatic lesion showed unique additional copy of chromosomal 7q, and loss of chromosome 9p24.3-q13 and chromosome 4, which included Melan A encoding gene region in 9p24.1. The above findings suggest the unique cytogenetic changes in the parotid lesion are most likely related to the metastatic behavior, as well as responsible for loss of multiple melanocytic marker expression in the metastatic melanoma for this case.

Neural systems for choice and valuation with counterfactual learning signals

The purpose of this experiment was to test a computational model of reinforcement learning with and without fictive prediction error (FPE) signals to investigate how counterfactual consequences contribute to acquired representations of action-specific expected value, and to determine the functional neuroanatomy and neuromodulator systems that are involved. 80 male participants underwent dietary depletion of either tryptophan or tyrosine/phenylalanine to manipulate serotonin (5HT) and dopamine (DA), respectively. They completed 80 rounds (240 trials) of a strategic sequential investment task that required accepting interim losses in order to access a lucrative state and maximize long-term gains, while being scanned. We extended the standard Q-learning model by incorporating both counterfactual gains and losses into separate error signals. The FPE model explained the participants' data significantly better than a model that did not include counterfactual learning signals. Expected value from the FPE model was significantly correlated with BOLD signal change in the ventromedial prefrontal cortex (vmPFC) and posterior orbitofrontal cortex (OFC), whereas expected value from the standard model did not predict changes in neural activity. The depletion procedure revealed significantly different neural responses to expected value in the vmPFC, caudate, and dopaminergic midbrain in the vicinity of the substantia nigra (SN). Differences in neural activity were not evident in the standard Q-learning computational model. These findings demonstrate that FPE signals are an important component of valuation for decision making, and that the neural representation of expected value incorporates cortical and subcortical structures via interactions among serotonergic and dopaminergic modulator systems.

The influence of food on the pharmacokinetics of amlodipine and losartan after single-dose of its compound tablets in healthy chinese subjects

We aim to identify the effects of food on the pharmacokinetics (PK) of amlodipine, losartan and losartan's active metabolite (EXP3174) after oral administration of the Compound Amlodipine Tablets with single dose in healthy Chinese subjects. 12 subjects took the compounds (10 mg/100 mg, amlodipine/losartan) at the conditions of a high-fat breakfast and an overnight fast with a washout period of 14 days. Plasma samples were obtained at scheduled time, and determined by HPLC-MS/MS for the concentrations of amlodipine and HPLC-MS for the concentrations of losartan and EXP3174, respectively. PK parameters were calculated using Software Drug and Statistics (Version 2.0). When tablets were co-administered with food, there was no significant difference of AUC for amlodipine and losartan, but the AUC of EXP3174 was reduced by 19.1%. Meanwhile, the Cmax of amlodipine, losartan and EXP3174 were reduced by 11.4%, 20.0% and 41.4%, and the Tmax of losartan and EXP3174 were 1.3 and 1.8 h longer, respectively. No significant difference was found at t1/2 following food intake. In conclusion, the Compound Amlodipine Tablets, are affected by food administration by reducing the AUC of EXP3174. It is thus suggested that the Compound Amlodipine Tablets should be administered 1 h before or 2 h after meal.

Application of (15)N- (18)O double stable isotope tracer technique in an agricultural nonpoint polluted river of the Yangtze Delta Region

One strategy to combat nitrate (NO3-N) contamination in rivers is to understand its sources. NO3-N sources in the East Tiaoxi River of the Yangtze Delta Region were investigated by applying a (15)N-(18)O dual isotope approach. Water samples were collected from the main channel and from the tributaries. Results show that high total N and NO3-N are present in both the main channel and the major tributaries, and NO3-N was one of the most important N forms in water. Analysis of isotopic compositions (δ (18)O, δD) of water suggests that the river water mainly originated from three tributaries during the sampling period. There was a wide range of δ (15)N-NO3 (-1.4 to 12.4 ‰) and a narrow range of δ (18)O-NO3 (3.7 to 9.0 ‰) in the main channel waters. The δ (15)N and δ (18)O-NO3 values in the upper, middle, and lower channels along the river were shifted as 8.2, 3.5, and 9.5 ‰, and 9.0, 4.2, and 6.0 ‰, respectively. In the tributary South Tiao, the δ (15)N and δ (18)O-NO3 values were as high as 9.5 and 7.0 ‰, while in the tributaries Mid Tiao and North Tiao, NO3-N in most of the samples had relatively low δ (15)N and δ (18)O-NO3 values from 2.3 to 7.5 ‰ and 4.7 to 7.0 ‰, separately. Our results also suggest that the dual isotope approach can help us develop the best management practice for relieving NO3-N pollution in the rivers at the tributary scale.

Occurrence of Grapevine Leafroll-Associated Viruses in China

To characterize the prevalence of viruses associated with grapevine leafroll disease in China, 249 grapevine (Vitis spp.) samples (86 popular cultivars and a rootstock) from 19 provinces and regions were collected and tested for Grapevine leafroll-associated virus 1 (GLRaV-1), GLRaV-2, GLRaV-3, GLRaV-4, and GLRaV-4 strain 5 by SYBR Green real-time reverse-transcription polymerase chain reaction (RT-PCR), and RT-PCR and sequencing. GLRaV-3 was found in 100% of the samples while GLRaV-1, GLRaV-2, and GLRaV-4 were detected in 24.9% (62/249), 15.3% (38/249), and 0.80% (2/249) of the samples, respectively. Single infections with GLRaV-3 were found in 66.3% (165/249) of the samples, and the remaining samples were mixed infections of GLRaV-3 with one or two other GLRaVs, those with GLRaV-1 being the most common (18.5%, 46/249). The genetic variability of Chinese GLRaV-3 isolates was characterized based on the coat protein (CP) gene. In total, 153 full-length CP gene sequences (94 sequences newly generated) of Chinese GLRaV-3 isolates from different grapevine-growing regions showed 89.3 to 100.0% and 92.7 to 100.0% identity at the nucleotide and amino acid levels, respectively. The average nucleotide diversity for the population of Chinese GLRaV-3 isolates was estimated at 0.037 (standard error = 0.0032). GLRaV-3 isolates from China segregated into five distinct phylogenetic groups and two novel recombination events were found in the viral population. This is the first and most extensive report of the prevalent species of GLRaV in China, which also provides an assessment of genetic variability of GLRaV-3 Chinese isolates.

Dosage of amyloid precursor protein affects axonal contact guidance in Down syndrome

Amyloid precursor protein (APP), encoded on Hsa21, functions as a cell adhesion molecule (CAM) in axonal growth cones (GCs) of the developing brain. We show here that axonal GCs of human fetal Down syndrome (DS) neurons (and of a DS mouse model) overexpress APP protein relative to euploid controls. We investigated whether DS neurons generate an abnormal, APP-dependent GC phenotype in vitro. On laminin, which binds APP and β1 integrins (Itgb1), DS neurons formed enlarged and faster-advancing GCs compared to controls. On peptide matrices that bind APP only, but not on those binding exclusively Itgb1 or L1CAM, DS GCs were significantly enlarged (2.0-fold), formed increased close adhesions (1.8-fold), and advanced faster (1.4-fold). In assays involving alternating stripes of monospecific matrices, human control GCs exhibited no preference for any of the substrates, whereas DS GCs preferred the APP-binding matrix (cross-over decreased significantly from 48.2 to 27.2%). Reducing APP expression in DS GCs with siRNA normalized most measures of the phenotype, including substrate choice. These experiments show that human DS neurons exhibit an APP-dependent, abnormal GC phenotype characterized by increased adhesion and altered contact guidance. The results suggest that APP overexpression may perturb axonal pathfinding and circuit formation in developing DS brain.

Micropthalmia transcription factor (MITF) as a diagnostic marker for metastatic melanomas negative for other melanoma markers

Metastatic malignant melanoma has a wide spectrum of histopathologic patterns and often lacks melanin pigment. Without a known primary tumor, the diagnosis of metastatic malignant melanoma relies on a combination of morphology and immunohistochemical profile. Infrequently, commonly used markers for melanoma (S100, HMB45, Melan-A and Tyrosinase A) are negative. These cases pose critical diagnostic challenges. Recent studies show that Microphthalmia Transcription Factor (MITF) has high sensitivity (88-100%) and specificity for metastatic melanoma. We are reporting here three cases of high grade tumors that were studied by a comprehensive immunohistochemical panel including cytokeratins, S100, HMB-45, Melan A, Tyrosinase, and MITF. All three tumors were also analyzed for the presence of BRAF mutations. All three metastatic tumors were negative for S100, Melan A, HMB-45 and Tyrosinase but positive for MITF. Subsequent to the diagnoses, previously existing or concurrent primary melanomas were identified in 2 of the 3 cases. Interestingly, S100, Melan A, and HMB-45 were positive in the primary tumors. No BRAF (V600E) mutations were identified in the three metastatic melanomas and CD 117 (c-kit) was positive in one of the cases. In summary, our experience shows that MITF can be a valuable adjunct in the diagnosis of metastatic tumors that are suspicious for melanoma but negative for other melanoma markers.

Different transcriptional responses of heat shock protein 70/90 in the marine diatom Ditylum brightwellii exposed to metal compounds and endocrine-disrupting chemicals

Environmental hazard assessments using diatoms have been well documented; however, their molecular toxicology has not been sufficiently studied. In this study, we characterized heat shock protein (HSP) 70/90 of the diatom Ditylum brightwellii (Db) and evaluated their transcriptional profiles in response to various environmental stresses (e.g., thermal shocks and metal and non-metal pollutants). Putative DbHSP70 (658aa, 71.7 kDa) and DbHSP90 (707aa, 80.2 kDa) proteins had conserved HSP family motifs but different C-terminus motifs, that is, "EEVD" in DbHSP70 and "MEEVD" in DbHSP90. Phylogenetic analyses of both proteins showed that D. brightwellii was well clustered with other diatoms. Real-time PCR analysis showed that thermal stress considerably upregulated DbHSP70 and DbHSP90. As for chemical pollutants, DbHSP70 greatly responded to CuSO4 and NiSO4 exposure, but not CuCl2 or NiCl2. However, DbHSP90 was significantly upregulated by all the metal compounds tested (CuSO4, NiSO4, CuCl2, and NiCl2). Strikingly, the expression of both genes was not induced by the organic pollutants tested, such as endocrine-disrupting chemicals. These data suggest that DbHSP70 and DbHSP90 are differentially involved in the defense response against various environmental stressors. Moreover, metal toxicity may be specifically affected by the conjugated anion in the metal compounds (e.g., SO4(2-) and Cl(-)).

Pharmacokinetic and bioequivalence studies of ibuprofen suspension after a single-dose administration in healthy Chinese volunteers

OBJECTIVE

The aim of this study was to assessed the pharmacokinetic and bioequivalence of 2 formulations of ibuprofen suspension.

METHOD

20 healthy volunteers were enrolled into this random, single-dose, 2-way crossover, open-label, single-centre, pharmacokinetic study. After overnight fasting, 2 formulations (test and reference) of ibuprofen (400 mg ibuprofen/20 mL suspension) were administered as a single dose on 2 treatment days separated by a 7-day washout period. After dosing, blood samples were drawn for a period of 12 h. The plasma samples were analyzed for the presence of ibuprofen by HPLC with ultraviolet detection. Pharmacokinetic parameters were determined from plasma concentrations for both formulations.

RESULTS

The main pharmacokinetics parameters of test and reference were as follows: t1/2 was (1.94±0.38) h and (1.95±0.28) h; Cmax was (33.41±7.83) μg · mL- 1 and (31.08±9.30) μg · mL- 1; AUC0-12 was (91.44±19.26) μg · mL-1 · h and (84.75±24.45) μg · mL-1 · h; AUC0-∞ was (92.82±19.94) μg · mL-1 · h and (85.97±24.99) μg · mL-1 · h; median Tmax was 0.5 h (range, 0.25, 2) and 0.5 h (range, 0.25, 1.5). The 90% confidence intervals of the test/reference treatment ratios for Cmax, AUC0-12 and AUC0-∞ were observed to be within the predetermined acceptable interval of 80-125%.

CONCLUSION

This single-dose study in healthy Chinese fasted volunteers was shown that the ibuprofen test and reference met the requirement of the State Food and Drug Administration, and the test and reference were bioequivalent.

Surgical incision induces phosphorylation of AMPA receptor GluR1 subunits at Serine-831 sites and GluR1 trafficking in spinal cord dorsal horn via a protein kinase Cγ-dependent mechanism

Spinal α-amino-3-hydroxy-5-methy-4-isoxazole propionate (AMPA) receptor plays an important role in acute pain induced by surgical tissue injuries. Our previous study has shown that the enhanced phosphorylation of AMPA receptor GluR1 subunits at Serine-831 sites by protein kinase C (PKC) in the spinal cord dorsal horn is involved in post-surgical pain hypersensitivity. However, which isoforms of PKC are responsible for the phosphorylation of AMPA receptor GluR1 subunits at Serine-831 sites remains to be established. In the present study, using an animal model of postoperative pain, we found that surgical tissue injuries enhanced the membrane translocation level of PKCγ, but not PKCα, βI, and βII, and induced the trafficking of GluR1, but not GluR2 into neuronal plasma membrane. Intrathecal (i.t.) pretreatment of small interfering RNA targeting PKCγ to reduce the PKCγ expression in the spinal cord significantly attenuated the pain hypersensitivity and inhibited the phosphorylation of AMPA receptor GluR1 subunits at Serine-831 sites as well as GluR1 membrane trafficking. Our study indicates that the surgical incision-induced phosphorylation of AMPA receptor GluR1 subunits at Serine-831 sites and GluR1 trafficking are regulated by a PKCγ-dependent mechanism.

OVERCOMING INCOMPATIBILITY PROBLEMS IN ELASTOMER BLENDS BY TAILORED SURFACE PROPERTIES OF RUBBER ADDITIVES

Rubber is a challenging composite material, whose functionality strongly depends on the affinity of the different materials in the composite and its morphology. One way to tailor polarity and chemistry of the filler surface is plasma coating. When using acetylene, thiophene, or pyrrole as monomers, the coating results in a reduced polarity of the filler compared with untreated silica, and unsaturated C–C bonds are formed on the surface. This improves the compatibility of the filler–polymer blends. In a SBR/EPDM blend, the filler–polymer compatibility is improved for all plasma-coated fillers compared with untreated silica. The best dispersion is achieved by plasma–pyrrole coating, as measured by the Payne effect and reinforcement parameter. The rubber–filler interaction is also highest for this blend, as measured by the bound rubber content. As expected, this results in improved tensile properties. In NBR/EPDM, the filler–filler interaction is significantly reduced by the plasma–pyrrole coating, which indicates a balanced compatibility of the pyrrole-treated silica in both polymers. The properties of the vulcanizate show the combinatorial effect of dispersion, filler–polymer interaction, polymer entanglements, and cross-link density. All plasma-treated, silica-filled NBR/EPDM materials show a considerable increase in tensile strength compared with untreated silica, with polyacetylene-treated silica resulting in the best properties. When plasma-coated curatives are used in SBR/EPDM blends, the scorch safety of the compounds is increased and the rupture energy is enhanced. In NBR/EPDM blends, all packages of the modified curatives provide an increased maximum torque compared with the control. Mechanical properties of the NBR/EPDM blend are improved even more than they are with SBR/EPDM. This indicates a more-balanced distribution of cross-links, along with a more-homogeneous carbon black dispersion over the different rubber phases. A better polarity match between additives and polymers usually results in improved material properties. The wide variety of monomers for the plasma polymerization allows researchers to tailor the surface properties of the additives.

A more rapid, sensitive, and specific HPLC-MS/MS method for nifedipine analysis in human plasma and application to a pharmacokinetic study

A more rapid, sensitive and specific high-performance liquid chromatography coupled to -tandem mass spectrometry (HPLC-MS/MS) was developed and validated for the quantification of nifedipine in human plasma, and applied to the pharmacokinetic study of nifedipine in Chinese healthy volunteers. Nifedipine and internal standard (IS) acetaminophen in plasma were extracted with ethyl acetate, separated on a C18 (150 mm×4.6 mm, 5 µm) reversed-phase column, eluted with acetonitrile mixed with 5 mM ammonium acetate solution (pH=6.62) (60:40, v/v), ionized by negative ion pneumatically assisted electrospray and detected in the multi-reaction monitoring mode using precursor→product ions of m/z 354.1→222.2 for nifedipine and 150.1→107.1 for the IS. A single oral dose of 20 mg nifedipine sustained release tablets and blood samples (4 mL) was collected before and 1, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 8, 12, 24, and 36 h after administration. The main pharmacokinetic parameters of nifedipine, as Tmax, t1/2α, t1/2β, t1/2z, Cmax, AUC0~36, AUC0~∞ were 2.80±0.50 h, 6.78±2.52 h, 6.82±2.53 h, 6.69±2.22 h, 76.69±19.51 (ng/mL), 546.49±162.28 (ng · h/mL) and 564.05±176.74 (ng · h/mL), respectively. The calibration curve was linear over the concentration range of 0.17-102 ng/mL (r2>0.99, n=5) with a lower limit of quantification (LLOQ) of 0.17 ng/mL. The intra- and inter-day precision was less than 15% for all quality control samples at concentrations of 0.42, 6.53 and 81.60 ng/mL and the accuracy (relative error, RE) was - 3.92% to 7.31% at 3 quality control levels. The specificity, matrix effect, recovery, sensitivity, linearity, accuracy, precision and stabilities were validated, and can fulfill the requirement of pharmacokinetic study of nifedipine sustained release tablets in Chinese volunteers.

Abstract P1-12-04: Carboplatin, nab-paclitaxel and bevacizumab as first-line treatment for metastatic breast cancer

Background: Bevacizumab added to weekly paclitaxel resulted in improved progression free survival (PFS) and objective response rates (ORR) compared to weekly paclitaxel alone. Nab-paclitaxel and the platins are active in MBC. We conducted an efficacy and safety study of carboplatin, nab-paclitaxel and bevacizumab.

Methods: A phase II open label prospective multi-site study enrolled patients (pts) who had measurable MBC according to RECIST 1.1 criteria and no prior chemotherapy for advanced disease. The primary endpoint was PFS with secondary endpoints of overall survival (OS), ORR, and safety. Pts initially received carboplatin AUC 6 day 1, 22,43, plus weekly nab-paclitaxel 100mg/m2 and bevacizumab 15mg/m2 day 1,22,43 of a 56 day cycle. This was later changed to carboplatin AUC 6 day 1, nab-paclitaxel 100mg/m2 day 1,8,15, and bevacizumab 10mg/m2 day 1,15 of a 28 day cycle. Thirty-two pts were required to detect an increase in median PFS from 6.7 to 10.5 mo with 80% power based on a one-sided p = 0.05. Kaplan–Meier analyses estimated PFS and OS. The log rank test was used for the comparison of survival curves between pts with triple negative MBC (TNBC) and pts with non-TNBC.

Results: Thirty-two pts were enrolled between 2/2008 and 11/2011 by 1 academic and 5 community oncology practices. Two pts were ineligible due to non-measurable disease and not included in the response analyses. The median age was 58 years (range 35–81), 22 pts (69%) had an ECOG PS 0, 9 (28%) had a PS 1, 1 (3%) PS 2. Twenty-four (75%) pts had ER+ disease, 7 (22%) had TNBC, 1 (3%) had ER-HER2+ disease not eligible for trastuzumab-based therapy. Metastatic sites were bone (26%), liver (18%), loco-regional (16%), and lung (12%). One pt (3%) had bone and loco-regional disease only, 19 (59%) had visceral dominant disease. The median number of weeks on treatment was 28.9 (range 5–131). The median PFS in all pts was 13.6 months (mo) (95% CI 11.2–21.9), with a median OS of 26.8 mo (95% CI 13.3–41.2). The ORR (2 CR and 18 PR) was 66.7% (CI 47.2–82.7). There also were 6 (20%) unconfirmed PR and 3 (10%) stable disease, resulting in a clinical benefit rate of 96.7% (CI 82.78–99.92). There was no significant difference in PFS (median 13.6 vs 16.1mo, p = 0.37) or OS (median 13.6 vs 26.8mo, p = 0.32) in pts with TNBC versus non-TNBC disease. The most common toxicities of any grade (gr) include neutropenia and thrombocytopenia in 24 pts (75%) each, leukopenia and fatigue in 17 pts (53%) each, anemia in 15 (47%), and neuropathy in 10 (31%). Gr 4 neutropenia was seen in 7 pts (22%) without febrile neutropenia, and gr 4 thrombocytopenia occurred in 6 (19%). There were no pts with gr 4 sensory neuropathy. All pts required chemotherapy dose delays, 15 (47%) had chemotherapy dose reductions.

Conclusions: The carboplatin, nab-paclitaxel and bevacizumab combination is highly effective with good tolerance in first line MBC. As the role of anti-angiogenic therapy in first line metastatic breast cancer is being clarified, this would be an attractive regimen to test in the (neo)adjuvant setting and together with novel molecular targeted agents.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-12-04.

Abstract PD10-02: Metabolic syndrome and recurrence within the 21-gene recurrence score assay risk categories in lymph node negative breast cancer

Background: The incidence of the metabolic syndrome (MS) has been increasing in the United States and elsewhere. The interaction of MS with breast cancer (BC) incidence, tumor biology and outcomes are under study. We hypothesized that the presence of MS would predict BC recurrence to a variable degree across the diverse BC biology as defined by the risk categories of the 21-gene recurrence score (RS) assay.

Patients and Methods: We studied consecutive patients (pts) with newly diagnosed, estrogen receptor (ER) positive, lymph node (LN) negative BC treated in our institution between 2006–2011 who had a 21-gene RS assay done on their tumors. All pts were treated with standard systemic and local therapy. The electronic medical record was queried for key diagnoses including MS and its constituent parts. The WHO definition was used to categorize pts as having MS defined as diabetes mellitus (DM) or glucose intolerance, plus at least 2 of the following: hypertension (HTN), dyslipidemia (HL), central obesity and microalbuminemia. Tumor characteristics including Ki67 index, grade, tumor size, HER2/neu status; and pt characteristics including age, race, menopausal status, body mass index were recorded. The association of MS and the tumor and patient characteristics with the RS tertiles of low, intermediate and high risk was analyzed.

Results: We identified 332 pts, median age 62 years, of whom 88 (27%) had MS. There was no significant association between the MS and any of the patient or tumor variables including the 21-gene RS assay, except for race (p = 0.004). Eleven of 21 (52%) African-American women had MS, 68 of 284 (24%) Caucasian women had MS, and 9 of 21 (43%) others including Hispanic and Asian women had MS. However, there was a significant association between recurrence and MS (p = 0.0002) independent of other factors. Of the 21 pts who recurred, 13 (61.9%) had MS. There was an association of recurrence and MS within RS tertiles. For pts with low risk scores, 7/44 (15.9%) with MS vs. 1/126 (0.79%) without MS had recurrence (p = 0.0003). For pts with intermediate risk scores, 5/30 (16.67%) with MS vs. 4/83 (4.82%) without MS had recurrence (p = 0.05). For patients with high risk scores, 1/9 (11.11%) with MS vs. 2/15 (13.33%) without MS had recurrence (p = 1).

Conclusion: MS is an independent risk factor for BC recurrence among women with LN negative, ER positive BC treated with standard adjuvant therapy. There is a striking impact of MS on recurrence in pts with tumor biologies defined by low (and to a lesser degree) intermediate risk 21-gene RS assay scores. However, there is no difference in recurrence risk by MS among those pts with high RS. This implies that interventions directed at modifying MS in newly diagnosed pts with early BC may potentially favorably impact survival in those with specific tumor biologies as defined by multigene assays. Thus, long-term prospective studies should be conducted to further evaluate both the short and long term effects of MS on BC outcomes.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD10-02.

Pharmacokinetics of ginkgolide B injection in beagle dogs

A liquid chromatography-mass spectrometry method was developed, validated, and applied to the pharmacokinetic study with doses of 0.68, 2.73 and 10.92 mg/kg of ginkgolide B in beagle dogs after intravenous infusion.An aliquot of blood samples were -collected, separated and quantitatively analyzed by liquid chromatography-mass spectrometry method with mobile phase of acetonitrile-0.02% ammonia solution (33:67, v/v) at a flow rate of 0.8 mL/min on the UltimateTM XB-C18 column (5 μm, 4.6×150 mm).The method was sensitive, accurate and convenient, and can be used for the determination of ginkgolide B in beagle dogs. The Cmax and AUC0-∞ of GB increased with dose escalation, but ANOVA analyses showed that no significant difference was observed in other pharmacokinetic parameters between different doses.An LC/MS method was developed with good sensitivity, reproducibility and specificity. In the pharmacokinetic study of GB in beagle dogs, linear pharmacokinetics was found at doses from 0.62 to 10.92 mg/kg after a single-dose intravenous infusion. Gender differences were not observed in the pharmacokinetics of GB.

Transcriptional responses of heat shock protein 70 (Hsp70) to thermal, bisphenol A, and copper stresses in the dinoflagellate Prorocentrum minimum

The heat shock protein 70 (Hsp70) family is an important part of the cell's machinery for protein folding, and helps to protect cells from environmental stress. Although Hsp70 functions have been discovered in various organisms, studies on dinoflagellate Hsps are limited, except for a few phylogenetic attempts. In this study, we sequenced the complete open reading frame of the dinoflagellate Prorocentrum minimum Hsp70 (PmHsp70), and characterized its molecular functions. The putative PmHsp70 protein contained 3 signature patterns of the Hsp70 family. Phylogenetic analysis revealed that PmHsp70 belonged to the dinoflagellate clade. Real-time (RT)-PCR analyses revealed that PmHsp70 was upregulated by thermal stress. Further, we examined the transcriptional response of PmHsp70 to copper (Cu) and bisphenol A (BPA) exposures. In toxicity assays, Cu and BPA exhibited EC(50)-72 h values of 1.07 ± 0.138 mg L(-1) and 1.51 ± 0.110 mg L(-1), respectively, in P. minimum. Expression of PmHsp70 was significantly upregulated in response to Cu and BPA exposures (one-way ANOVA, P<0.05). PmHsp70 displayed different expression patterns in response to different concentrations of Cu and BPA. This study evaluated typical characteristics and, for the first time, toxicant-related functions of PmHsp70. The results suggest that Hsp70 genes may play a vital role in the environmental stress responses of dinoflagellates.