Abstract PD5-08: A biparatopic HER2-targeting antibody-drug conjugate demonstrates potent antitumor activity in primary tumor models that are refractory to or ineligible for HER2-targeted therapies

Current HER2-targeted drugs are ineffective in killing cancer cells expressing relatively low levels of HER2. Therefore, more than 60% of breast cancer patients are ineligible for HER2-targeted therapies because of lack of HER2 overexpression and the vast majority of eligible patients who initially respond to the treatment will eventually relapse. MedImmune is developing a novel HER2-targeting antibody-drug conjugate (ADC) to address this unmet medical need. We show that a bivalent biparatopic antibody targeting two distinct non-overlapping epitopes on HER2 is able to induce receptor clustering on the tumor cell surface, which in turn facilitates internalization and promotes lysosomal trafficking and degradation. When conjugated with a tubulysin-based microtubule inhibitor, the biparatopic antibody can deliver a greater quantity of cytotoxin into the targeted cancer cells. As a result, it demonstrated superior antitumor activity over Kadcyla® (T-DM1) in HER2-overexpressing (HER2-positive) tumor models. It also induced complete tumor regression in a HER2-positive tumor model that had developed acquired resistance to T-DM1 through chronic exposure. Moreover, to explore the potential clinical applications in treating the HER2 non-overexpressing (HER2-negative) patients the biparatopic ADC was evaluated across 17 primary tumor models derived from HER2-negative breast cancer patients among which 13 were triple-negative. Other criteria were also considered in the selection of these 17 models, including the degree of heterogeneity in HER2 expression, ER/PR status and histopathologic subclass, to maximize the diversity of tumor subtypes in the study. The biparatopic ADC demonstrated potent antitumor activity regardless of the histopathologic subclass and ER/PR status of the tumor. At the dose of 1 mg/kg, 41% of the tumor models (7 out of 17) showed tumor regression and 6% (1 out of 17) showed tumor stasis. At the dose of 3 mg/kg, 71% of the models (12 out of 17) showed tumor regression and 12% (2 out of 17) showed tumor stasis. Overall, our findings underscore the potential use of this novel HER2-targeting ADC to treat a large patient population that is ineligible for or relapsed/refractory to current HER2-targeted therapies, and thus warrant investigation in the clinic.

Citation Format: Li JY, Perry SR, Muniz-Medina V, Wetzel LK, Rebelatto MC, Bezabeh BZ, Fleming RL, Dimasi N, Gao C, Wu H, Jenkins DW, Osbourn JK, Coats SR. A biparatopic HER2-targeting antibody-drug conjugate demonstrates potent antitumor activity in primary tumor models that are refractory to or ineligible for HER2-targeted therapies. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr PD5-08.

Association of COL4A1 gene polymorphisms with cerebral palsy in a Chinese Han population

The basement membrane (BM) is an extracellular matrix associated with overlying cells and is important for proper tissue development, stability, and physiology. COL4A1 is the most abundant component of type IV collagen in the BM, and COL4A1 variants can present with variable phenotypes that might be related to cerebral palsy (CP). We postulated, therefore, that variations in the COL4A1 gene might play an important role in the etiology of CP. In this study, six single nucleotide polymorphisms (SNPs) in the COL4A1 gene were genotyped among 351 CP patients and 220 healthy controls from the Chinese Han population. Significant association was found for an association between CP and rs1961495 (allele: p = 0.008, odds ratio (OR) = 1.387, 95% confidence interval (CI) = 1.088-1.767) and rs1411040 (allele: p = 0.009, OR = 1.746, 95% CI = 1.148-2.656) SNPs of the COL4A1 gene. Multifactor dimensionality reduction analysis suggested that these SNPs had interactive effects on the risk of CP. This study is the first attempt to investigate the contribution of polymorphisms in the COL4A1 gene to the susceptibility of CP in a Chinese Han population. This study shows an association of the COL4A1 gene with CP and suggests a potential role of COL4A1 in the pathogenesis of CP.

Highly accurate fiber transfer delay measurement with large dynamic range

A novel and efficient method for fiber transfer delay measurement is demonstrated. Fiber transfer delay measurement in time domain is converted into the frequency measurement of the modulation signal in frequency domain, accompany with a coarse and easy ambiguity resolving process. This method achieves a sub-picosecond resolution, with an accuracy of 1 picosecond, and a large dynamic range up to 50 km as well as no measurement dead zone.

Tubular organ epithelialisation

Hollow, tubular organs including oesophagus, trachea, stomach, intestine, bladder and urethra may require repair or replacement due to disease. Current treatment is considered an unmet clinical need, and tissue engineering strategies aim to overcome these by fabricating synthetic constructs as tissue replacements. Smart, functionalised synthetic materials can act as a scaffold base of an organ and multiple cell types, including stem cells can be used to repopulate these scaffolds to replace or repair the damaged or diseased organs. Epithelial cells have not yet completely shown to have efficacious cell-scaffold interactions or good functionality in artificial organs, thus limiting the success of tissue-engineered grafts. Epithelial cells play an essential part of respective organs to maintain their function. Without successful epithelialisation, hollow organs are liable to stenosis, collapse, extensive fibrosis and infection that limit patency. It is clear that the source of cells and physicochemical properties of scaffolds determine the successful epithelialisation. This article presents a review of tissue engineering studies on oesophagus, trachea, stomach, small intestine, bladder and urethral constructs conducted to actualise epithelialised grafts.

Conformational Dynamics of o-Fluoro-Substituted Z-Azobenzene

A conformational analysis of o-fluoro Z-azobenzene reveals a slight preference for aromatic C-F/π interaction. Density functional theory (DFT) indicates that the conformation with a C-F/π interaction is preferred by approximately 0.3-0.5 kcal/mol. Ground-state conformations were corroborated with X-ray crystallography. (Z)-Azobenzene (Z-AB) with at least one o-fluoro per ring displays (19)F-(19)F through-space (TS) coupling. 2D J-resolved NMR was used to distinguish through-bond from TS coupling ((TS)JFF). (TS)JFF decreases as the temperature is lowered and the multiplets coalesce into broad singlets. We hypothesize that the coalescence temperature (Tc) corresponds to the barrier for phenyl rotation. The experimentally determined barrier of 8-10 kcal/mol has been qualitatively verified by DFT where transition states with a bisected geometry were identified with zero-point energies of 6-9 kcal/mol relative to ground state. These values are significantly higher that values estimated from previous theoretical studies but lie within a reasonable range for phenyl rotation in hydrocarbon systems.

Temporal and Spatial Changes in Black Carbon Sedimentary Processes in Wetlands of Songnen Plain, Northeast of China

Black carbon (BC), an important component of organic carbon (OC) produced from incomplete combustion of carbon compounds, is widespread and affects the global carbon storage. The objectives of this study were to analyze the BC contents and fluxes in the last 150 years to determine the causes of differences in the three profiles of the Songnen Plain of Northeast China and to estimate the BC storage in the wetlands of the Songnen Plain. In the three sampling sites, BC fluxes in the period between 1950 and the present time increased by the ratios of 1.3, 31.1 and 1.4, respectively, compared to their own baseline between 1850 and 1900. Furthermore, the BC fluxes varying from 0.76 to 5.63 g m-2 y-1 in the three profiles had an opposite trend with the sand percentages with mean values changing from 78.9% to 19.6%, suggesting that sand desertification might additionally affect the BC processes in the region.

[Survey on the early reperfusion therapy status in patients with ST-segment elevation myocardial infarction hospitalized in tertiary and secondary hospitals in Henan province]

OBJECTIVE

To observe the early reperfusion therapy status for patients with ST elevation acute myocardial infarction (STEMI) hospitalized in tertiary and secondary hospitals in Henan province.

METHODS

Baseline data, early reperfusion treatment and in-hospital mortality of STEMI patients hospitalized in 17 hospitals in Henan province (8 tertiary hospitals, 9 secondary hospitals) from June 2011 to June 2012 were obtained using a uniformed questionnaire.

RESULTS

One thousand six hundred and eighty six patients were enrolled, of which 886 patients were hospitalized in tertiary hospitals and 880 patients were early hospitalized in secondary hospitals. Six hundred and fifty four patients (38.8%, 654/1 686) underwent early reperfusion therapy (543 with thrombolysis and 111 with primary percutaneous coronary intervention (PCI)). There was no difference in the proportion of early reperfusion therapy between tertiary and secondary hospitals (40.1% (355/886) vs. 37.4% (299/800), P = 0.257). The median time from symptom onset to first medical contact, door-to-needle and door-to-balloon was 132 min, 18 min and 60 min, respectively. The median time from symptom onset to first medical contact (150 min vs. 120 min, P = 0.001), door-to-needle (30 min vs. 18 min, P = 0.003) and symptom onset-to-thrombolysis (3.5 h vs. 2.7 h, P = 0.001) were significantly longer in tertiary hospitals than in secondary hospitals. No difference was found in median time of door-to-balloon, symptom onset-to-primary PCI or symptom onset-to-elected PCI between tertiary and secondary hospitals (all P > 0.05). The proportion of door-to-needle ≤ 30 min was lower in tertiary hospitals than in secondary hospitals (46.4% (84/181) vs. 62.2% (153/246), P = 0.001). However, there was no difference in the proportion of door-to-balloon ≤ 90 min between tertiary and secondary hospitals (58.8% (60/102) vs. 57.1% (4/7), P = 1.000). In-hospital mortality was also similar between tertiary and secondary hospitals (5.8% (51/886) vs. 5.5% (44/800), P = 0.820).

CONCLUSIONS

Early reperfusion rate is low, and thrombolysis is the main early reperfusion therapy in both tertiary and secondary hospitals in Henan province. Tertiary hospitals did not take advantage of their primary PCI capability. There is great room for improvement in early reperfusion therapy in tertiary and secondary hospitals.

Automated anthropometric phenotyping with novel Kinect-based three-dimensional imaging method: comparison with a reference laser imaging system

BACKGROUND/OBJECTIVES

Anthropometry for measuring body composition, shape, surface area and volume is important for human clinical research and practice. Although training and technical skills are required for traditional tape and caliper anthropometry, a new opportunity exists for automated measurement using newly developed relatively low-cost three-dimensional (3D) imaging devices. The aim of this study was to compare results provided by a Kinect-based device to a traditional laser 3D reference system.

SUBJECTS/METHODS

Measurements made by the evaluated device, a hybrid of commercially purchased hardware (KX-16; TC(2), Cary, NC, USA) with our additional added software, were compared with those derived by a high-resolution laser scanner (Vitus Smart XXL; Human Solutions North America, Cary, NC, USA). Both imaging systems were compared with additional linear (stadiometer-derived height) and volumetric (total volume, air-displacement plethysmography) measurements. Subjects (n=101) were healthy children (age ≥5 years) and adults varying in body mass index.

RESULTS

Representative linear (4), circumferential (6), volumetric (3) and surface area (1) measurements made by the Kinect-based device showed a consistent pattern relative to the laser system: high correlations (R(2)s= 0.70-0.99, all P<0.001); 1-3% differences for large linear (for example, height, X±s.d., -1.4±0.5%), circumferential (for example, waist circumference, -2.1±1.8%), volume (for example, total body, -0.8±2.2%) and surface area (whole-body, -1.7±2.0%) estimates. By contrast, mean measurement differences were substantially larger for small structures (for example, forearm volume, 31.3±31.4%).

CONCLUSIONS

Low-cost 3D Kinect-based imaging systems have the potential for providing automated accurate anthropometric and related body measurements for relatively large components; further hardware and software developments may be able to improve system small-component resolution.

Protective role of Osthole on myocardial cell apoptosis induced by doxorubicin in rats

OBJECTIVE

To explore the effect of Osthole on protecting myocardial cell apoptosis induced by doxorubicin during cardiac failure in rats.

METHODS

Myocardial cells isolated from the newborn SD rats were separated into three groups: cells treated with 1 μmol doxorubicin, cells treated with Osthole at three concentrations of 10, 20, and 40 μmol, cells treated neither with Osthole nor with doxorubicin were the control groups. Consequently, cell apoptosis of myocardial cells in each group was analyzed using TUNEL assay. Also, expressions of oxidase, NADPH, and ROS in myocardial cells were analyzed using different biological methods. Moreover, expressions of cell apoptosis associated proteins were analyzed using Western blotting.

RESULTS

Compared with the controls, the results showed that cells received Osthole and doxorubicin treatments performed high percentage of cell apoptosis, suggesting that Osthole could anesis myocardial cell apoptosis induced by doxorubicin (P<0.05). Osthole of 10 μmol depressed the expressions of cell apoptosis associated proteins including Caspase-3 and Cytc, and enhancing expression of Bcl-XL expression (P<0.05). Osthole of 20 μmol significantly decreased the generation of intracellar superoxidase, NADPH, and NADPH activity in myocardial cells treated with doxorubicin (P<0.05). Moreover, Osthole of 20 μmol could significantly increase phosphorylated elF2α level in cells.

CONCLUSION

Our study suggested that Osthole may play a protective role in suppressing myocardial apoptosis induced by doxorubicin through inhibiting NADPH and superoxidase production and downstream phosphorylated elF2α.

Dissemination stability and phase noise characteristics in a cascaded, fiber-based long-haul radio frequency dissemination network

To study the dissemination stability and phase noise characteristics of the cascaded fiber-based RF dissemination, we perform an experiment using three sets of RF modulated frequency dissemination systems. The experimental results show that the total transfer stability of the cascaded system can be given by σ(T)(2)=∑(i=1)(N)σ(i)(2) (σ(i) is the frequency dissemination stability of the ith segment and N is the quantity of segments). Furthermore, for each segment, the phase noise of recovered frequency signal is also measured. The results show that for an N-segment, cascaded dissemination system, its stability degrades only by a factor of N. This sub-linear relation makes the cascaded, RF-dissemination method a very attractive one for long-haul, time and frequency dissemination network.

Inactivation of INK4a and ARF induces myocardial proliferation and improves cardiac repair following ischemia‑reperfusion

The growth of the heart during mammalian embryonic development is primarily dependent on an increase in the number of cardiomyocytes (CM). However, shortly following birth, CMs cease proliferating and further growth of the myocardium is achieved via hypertrophic expansion of the existing CM population. The cyclin-dependent kinase inhibitor 2A (Cdkn2a) locus encodes overlapping genes for two tumor suppressor proteins, p16INK4a and p19 alternative reading frame (ARF). To determine whether decreased Cdkn2a gene expression results in improved cardiac regeneration in vitro and in vivo following cardiac injury, the proliferation of CMs isolated from Cdkn2a knockout (KO) and wild‑type (WT) mice in vitro and in vivo were evaluated following generation of ischemia reperfusion (IR) injury. The KO mice demonstrated enhanced CM proliferation not only in vitro, but also in vivo. Furthermore, heart function was improved and scar size was decreased in the KO mice compared with that of the WT mice. The results also indicated that microRNA (miR)‑1 and miR‑195 expression levels associated with cell proliferation were reduced following IR injury in KO mice compared with those of WT mice. These results suggested that the inactivation of INK4a and ARF stimulated CM proliferation and promoted cardiac repair.

Routine early versus deferred provisional tirofiban treatment in patients with acute coronary syndrome undergoing percutaneous coronary intervention

The present study examined the optimal timing of tirofiban administration in moderate- or high-risk non-ST segment elevated acute coronary syndrome (NSTE-ACS) patients undergoing percutaneous coronary intervention (PCI). Eligible patients were randomized into two groups. Tirofiban was administered routinely at ≥ 4 h before angiography (routine early group; n = 141 patients) or provisionally only for bailout after angiography (deferred provisional group; n = 145 patients). The parameters analysed were: creatine kinase MB isoenzyme (CK-MB), thrombolysis in myocardial infarction (TIMI) flow, thrombotic complications during PCI, efficacy end-points (death, myocardial infarction or target vessel revascularization) at 7, 30 and 180 days and safety end-points (bleeding or thrombocytopenia). In the deferred provisional group, 48 patients (33.1%) required bailout tirofiban. Tirofiban was administered 5.8 h earlier in the routine early compared with the deferred provisional group. The routine early group showed a lower percentage increase in CK-MB (in U/L) 12-24 h after PCI compared with the deferred provisional group (0 (-4.0, 3.0) vs 0.4 (-3.0, 5.0), respectively; P = 0.045), as well as higher pre-PCI TIMI 3 (i.e. normal) flow (78.7% vs 64.8%, respectively; P = 0.042) and a lower incidence of thrombotic events (5.0% vs 33.1%, respectively; P < 0.0001). There were no significant differences in efficacy and safety end-points. In patients with moderate- or high-risk NSTE-ACS, early tirofiban combined with dual antiplatelet therapy was associated with better patency before PCI, attenuated minor myocardial damage and a lower prevalence of thrombotic complications during PCI, but had no significant benefit on the post-PCI TIMI 3 flow or short-term prognosis.

Visualisation of dual radiolabelled poly(lactide-co-glycolide) nanoparticle degradation in vivo using energy-discriminant SPECT

The determination of nanoparticle (NP) stability and degradation in vivo is essential for the accurate evaluation of NP biodistribution in medical applications and for understanding their toxicological effects. Such determination is particularly challenging because NPs are extremely difficult to detect and quantify once distributed in a biological system. Radiolabelling with positron or gamma emitters and subsequent imaging studies using positron emission tomography (PET) or single-photon emission computerised tomography (SPECT) are some of the few valid alternatives. However, NPs that degrade or radionuclides that detach or are released from the NPs can cause artefact. Here, submicron-sized poly(lactide-co-glycolide) nanoparticles (PLGA-NPs) stabilised with bovine serum albumin (BSA) were dual radiolabelled using gamma emitters with different energy spectra incorporated into the core and coating. To label the core, ¹¹¹In-doped iron oxide NPs were encapsulated inside PLGA-NPs during NP preparation, and the BSA coating was labelled by electrophilic substitution using ¹²⁵I. After intravenous administration into rats, energy-discriminant SPECT resolved each radioisotope independently. Imaging revealed different fates for the core and coating, with a fraction of the two radionuclides co-localising in the liver and lungs for long periods of time after administration, suggesting that NPs are stable in these organs. Organ harvesting followed by gamma counting corroborated the SPECT results. The general methodology reported here represents an excellent alternative for visualising the degradation process of multi-labelled NPs in vivo and can be extended to a wide range of engineered NPs.

The consensus sequence of FAMLF alternative splice variants is overexpressed in undifferentiated hematopoietic cells

The familial acute myeloid leukemia related factor gene (FAMLF) was previously identified from a familial AML subtractive cDNA library and shown to undergo alternative splicing. This study used real-time quantitative PCR to investigate the expression of the FAMLF alternative-splicing transcript consensus sequence (FAMLF-CS) in peripheral blood mononuclear cells (PBMCs) from 119 patients with de novo acute leukemia (AL) and 104 healthy controls, as well as in CD34+ cells from 12 AL patients and 10 healthy donors. A 429-bp fragment from a novel splicing variant of FAMLF was obtained, and a 363-bp consensus sequence was targeted to quantify total FAMLF expression. Kruskal-Wallis, Nemenyi, Spearman's correlation, and Mann-Whitney U-tests were used to analyze the data. FAMLF-CS expression in PBMCs from AL patients and CD34+ cells from AL patients and controls was significantly higher than in control PBMCs (P < 0.0001). Moreover, FAMLF-CS expression in PBMCs from the AML group was positively correlated with red blood cell count (rs =0.317, P=0.006), hemoglobin levels (rs = 0.210, P = 0.049), and percentage of peripheral blood blasts (rs = 0.256, P = 0.027), but inversely correlated with hemoglobin levels in the control group (rs = -0.391, P < 0.0001). AML patients with high CD34+ expression showed significantly higher FAMLF-CS expression than those with low CD34+ expression (P = 0.041). Our results showed that FAMLF is highly expressed in both normal and malignant immature hematopoietic cells, but that expression is lower in normal mature PBMCs.

MiR-200c sensitizes clear-cell renal cell carcinoma cells to sorafenib and imatinib by targeting heme oxygenase-1

Clear-cell renal cell carcinoma is a highly treatment-resistant tumor type. Heme oxygenase-1 plays an anti-apoptotic role in cancer chemotherapeutic inducing tumor-progression. The miR-200 family was involved in the process of mesenchymal-epithelial transition (MET) during renal development. In the present study, we demonstrated the regulatory relationship between miR-200c and HO-1. We provided evidences to elucidate that miR-200c could sensitize ccRCC cells to sorafenib or imatinib to inhibit cell proliferation, at least partly by targeting HO-1. Moreover, the correlation between miR-200c and HO-1 expression level and drug resistance in ccRCC was also determined. Combined application with chemotherapeutic drugs, miR-200c, a HO-1 inhibitor, may enhance the efficiency of therapy by promoting both apoptosis and autophagy.

Measurement of pion, kaon and proton production in proton-proton collisions at [Formula: see text] TeV

The measurement of primary [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] production at mid-rapidity ([Formula: see text] 0.5) in proton-proton collisions at [Formula: see text][Formula: see text] 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/[Formula: see text] for pions, from 0.2 up to 6 GeV/[Formula: see text] for kaons and from 0.3 up to 6 GeV/[Formula: see text] for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

Optimization of derivatization procedure and gas chromatography-mass spectrometry method for determination of bensulfuron-methyl herbicide residues in water

A simple and efficient technique based on liquid phase extraction with CH2Cl2 solvent followed by derivatization with (C2H5)2O·BF3 solution and confirmation analysis with GC-MS analytical method was developed for detecting the bensulfuron-methyl (BSM) residues in water. Box-Behnken response surface methodology was employed for optimization of the derivatization efficiency. According to the optimization model, the derivatization time of 45min, derivatization temperature at 55°C and 0.2mL (C2H5)2O·BF3 solvent were selected as the optimal derivatization condition for obtaining the maximum desirability of response. Method validation was performed at 6 working standard levels (0.05, 0.1, 0.2, 0.5, 1.0, 5.0μg/mL) and the linearity of the calibration curve was linear well over the 6 fortification levels with the squared correlation coefficient of determination r(2)=0.998 and the LOD was found to be 0.1μg/L for BSM herbicide. The mean value of BSM was detected from 0.0414 to 4.7542μg/mL at levels from 0.05 to 5μg/mL with the recoveries remained at the acceptable level (42.8-95.0%) with the RSD values from 3.5% to 6.2%, which is more accptable and desirable than the results obtained by LC methods. Moreover, the method allowed the determination of BSM residue in real paddy field water samples at concentrations between 0.0902 and 3.4605μg/L. Average recovery rates of the BSM spiked at levels 0.1, 0.2, 0.5, 1.0μg/mL into thirty water samples ranged from 74.1% and 94.1% with the relative standard derivation (RSD) values from 1.9% to 6.7%.

Effects of Renal Denervation from the Intima and the Adventitia of Renal Arteries on Renal Sympathetic Nerve Activity in Dogs: A Comparative Study

OBJECTIVES

This study was designed to observe the efficacy and safety of renal denervation from the inside and outside of renal arteries.

METHODS

Fourteen beagles were randomly divided into a control group (n = 4) and treatment group (n = 10). One renal artery in every beagle of the treatment group was randomly assigned to an intimal group (10 renal arteries) which underwent percutaneous renal denervation from the inside, and another renal artery was assigned to an adventitial group (10 renal arteries) which underwent renal denervation from the outside by laparotomy.

RESULTS

Compared with the intimal group, the renal norepinephrine (NE) concentration in the adventitial group had significantly decreased (p = 0.003) at 3 months postsurgery. Renal artery HE staining showed that the perineurium from the adventitial group appeared thickened. Western blotting showed that renal tissue tyrosine hydroxylase (TH) protein expression in the adventitial group was significantly lower than that in the intimal group (p < 0.01) at 3 months postsurgery. There was a renal artery stenosis and a renal atrophy in the intimal group after 1 month of follow-up.

CONCLUSION

The inhibitory effect on renal sympathetic nerve activity was more effective in the adventitial group than the intimal group, and renal denervation in the former group was safe.