Beam Spin Asymmetry in Semi-Inclusive Electroproduction of Hadron Pairs

A first measurement of the longitudinal beam spin asymmetry A_{LU} in the semi-inclusive electroproduction of pairs of charged pions is reported. A_{LU} is a higher-twist observable and offers the cleanest access to the nucleon twist-3 parton distribution function e(x). Data have been collected in the Hall-B at Jefferson Lab by impinging a 5.498-GeV electron beam on a liquid-hydrogen target, and reconstructing the scattered electron and the pion pair with the CLAS detector. One-dimensional projections of the A_{LU}^{sinϕ_{R}} moments are extracted for the kinematic variables of interest in the valence quark region. The understanding of dihadron production is essential for the interpretation of observables in single-hadron production in semi-inclusive DIS, and pioneering measurements of single-spin asymmetries in dihadron production open a new avenue in studies of QCD dynamics.

CERKL is upregulated in cutaneous squamous cell carcinoma and maintains cellular sphingolipids and resistance to oxidative stress

BACKGROUND

Ceramide kinase-like protein (CERKL) was originally described in retinal tissue. CERKL has been shown to protect cells from oxidative stress, and mutations in CERKL underlie the inherited disease retinitis pigmentosa. CERKL expression maintains cellular sphingolipids via an unknown mechanism.

OBJECTIVES

To determine whether CERKL is expressed in epidermis and cutaneous squamous cell carcinoma (cSCC) and whether CERKL expression affects cSCC sphingolipid metabolism and susceptibility to oxidative stress.

METHODS

CERKL expression was determined by RNA-Seq, quantitative polymerase chain reaction and immunohistochemistry. CERKL was knocked down in cSCC cells using small interfering RNA. Sphingolipid content was analysed by liquid chromatography-mass spectrometry. Oxidative stress was induced by treatment with H₂ O₂ , and apoptosis was measured using flow cytometry to determine annexin V binding.

RESULTS

CERKL mRNA and protein are highly expressed in actinic keratosis and cSCC in comparison with normal epidermis. CERKL is also expressed in metabolically active epithelial cells in normal hair bulbs and sebaceous glands. CERKL knockdown in cultured cSCC cells reduces cellular sphingolipid content and enhances susceptibility to oxidative stress.

CONCLUSIONS

These findings suggest that CERKL may be important in cSCC progression and could lead to novel strategies for prevention and treatment of cSCC.

B7-H3×4-1BB bispecific antibody augments antitumor immunity by enhancing terminally differentiated CD8+ tumor-infiltrating lymphocytes

Cancer immunotherapy with 4-1BB agonists has limited further clinical development because of dose-limiting toxicity. Here, we developed a bispecific antibody (bsAb; B7-H3×4-1BB), targeting human B7-H3 (hB7-H3) and mouse or human 4-1BB, to restrict the 4-1BB stimulation in tumors. B7-H3×m4-1BB elicited a 4-1BB-dependent antitumor response in hB7-H3-overexpressing tumor models without systemic toxicity. BsAb primarily targets CD8 T cells in the tumor and increases their proliferation and cytokine production. Among the CD8 T cell population in the tumor, 4-1BB is solely expressed on PD-1⁺Tim-3⁺ "terminally differentiated" subset, and bsAb potentiates these cells for eliminating the tumor. Furthermore, the combination of bsAb and PD-1 blockade synergistically inhibits tumor growth accompanied by further increasing terminally differentiated CD8 T cells. B7-H3×h4-1BB also shows antitumor activity in h4-1BB-expressing mice. Our data suggest that B7-H3×4-1BB is an effective and safe therapeutic agent against B7-H3-positive cancers as monotherapy and combination therapy with PD-1 blockade.

Economic Studies Reinforce Efforts to Safeguard Specialty Crops in the United States

Pathogen-tested foundation plant stocks are the cornerstone of sustainable specialty crop production. They provide the propagative units that are used to produce clean planting materials, which are essential as the first-line management option of diseases caused by graft-transmissible pathogens such as viruses, viroids, bacteria, and phytoplasmas. In the United States, efforts to produce, maintain, and distribute pathogen-tested propagative material of specialty crops are spearheaded by centers of the National Clean Plant Network (NCPN). Agricultural economists collaborated with plant pathologists, extension educators, specialty crop growers, and regulators to investigate the impacts of select diseases caused by graft-transmissible pathogens and to estimate the return on investments in NCPN centers. Economic studies have proven valuable to the NCPN in (i) incentivizing the use of clean planting material derived from pathogen-tested foundation plant stocks; (ii) documenting benefits of clean plant centers, which can outweigh operating costs by 10:1 to 150:1; (iii) aiding the development of disease management solutions that are not only ecologically driven but also profit maximizing; and (iv) disseminating integrated disease management recommendations that resonate with growers. Together, economic studies have reinforced efforts to safeguard specialty crops in the United States through the production and use of clean planting material.

Preparation and Characterization of Reduced Graphene Oxide Based Natural Rubber Nanocomposites

This work describes the effect of reduced graphene oxide (RGO) addition in natural rubber (NR). Firstly, RGO was synthesized based on the improved Hummer’s method then characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA) to confirm that the RGO surface contains hydroxyl, epoxy, and carboxyl functional groups to improve graphene interaction with the NR matrix. In a second step, the synthesized RGO was predispersed in NR latex using the co-coagulation technique then added at different amounts (0 to 2 parts per hundred rubber (phr)) to a basic NR formulation and compounded in an internal mixer. The results show that the crosslink density of the developed NR/RGO nanocomposites increased by 65% for RGO concentration of 2.0 phr. For the same RGO concentration, a significant increase in tensile strength (53%) and Young’s modulus (31%) were also observed. Finally, a significant improvement (26%) of the thermal conductivity was obtained with the addition of only 0.5 phr of RGO.

CERKL is Upregulated in Cutaneous Squamous Cell Carcinoma and Maintains Cellular Sphingolipids and Resistance to Oxidative Stress

BACKGROUND

Ceramide Kinase-Like Protein (CERKL) was originally described in retinal tissue. CERKL has been shown to protect cells from oxidative stress, and mutations in CERKL underlie the inherited disease, retinitis pigmentosa. CERKL expression maintains cellular sphingolipids via an unknown mechanism.

OBJECTIVES

To determine whether CERKL is expressed in epidermis and cutaneous squamous cell carcinoma (cSCC) and whether CERKL expression affects cSCC sphingolipid metabolism and susceptibility to oxidative stress.

METHODS

CERKL expression was determined by RNA-Seq, qPCR and immunohistochemistry. CERKL was knocked down in cSCC cells using siRNA. Sphingolipid content was analyzed by liquid chromatography-mass spectrometry (LC-MS). Oxidative stress was induced by treatment with H2 O2 , and apoptosis was measured using flow cytometry to determine annexin v binding.

RESULTS

CERKL mRNA and protein are highly expressed in actinic keratosis and cSCC in comparison with normal epidermis. CERKL also is expressed in metabolically active epithelial cells in normal hair bulbs and sebaceous glands. CERKL knockdown in cultured cSCC cells reduces cellular sphingolipid content and enhances susceptibility to oxidative stress.

CONCLUSIONS

These findings suggest that CERKL may be important in cSCC progression and could lead to novel strategies for prevention and treatment of cSCC.

Extraction of Beam-Spin Asymmetries from the Hard Exclusive π^{+} Channel off Protons in a Wide Range of Kinematics

We have measured beam-spin asymmetries to extract the sinϕ moment A_{LU}^{sinϕ} from the hard exclusive e[over →]p→e^{'}nπ^{+} reaction above the resonance region, for the first time with nearly full coverage from forward to backward angles in the center of mass. The A_{LU}^{sinϕ} moment has been measured up to 6.6  GeV^{2} in -t, covering the kinematic regimes of generalized parton distributions (GPD) and baryon-to-meson transition distribution amplitudes (TDA) at the same time. The experimental results in very forward kinematics demonstrate the sensitivity to chiral-odd and chiral-even GPDs. In very backward kinematics where the TDA framework is applicable, we found A_{LU}^{sinϕ} to be negative, while a sign change was observed near 90° in the center of mass. The unique results presented in this Letter will provide critical constraints to establish reaction mechanisms that can help to further develop the GPD and TDA frameworks.

The metabolic suppressor 3-iodothyronamine enhances lipolysis in 3T3-L1 adipocytes via activation of the adenosine monophosphate-activated protein kinase/forkhead box O1 signaling pathway

Obesity is a major health concern in modern societies as it is linked to diverse chronic diseases, such as diabetes, cancer, stroke, and skeletomuscular disorders. This study aimed to investigate the lipolytic potency of the metabolic suppressor 3-iodothyronamine (T1AM) and its molecular mechanism in differentiated 3T3-L1 adipocytes. Cells stained with Oil Red O showed a remarkable accumulation of lipid droplets by 20-d post-differentiation and a plateau at 26 - 30 day. Treatment with 100 μM T1AM for 6 h increased the liberation of free fatty acids (FFAs) and glycerol (P < 0.05) detected in the culture media. However, this stimulatory effect was significantly suppressed by ATGListatin, an inhibitor of adipose triglyceride lipase (ATGL), suggesting that ATGL plays a rate-limiting role in triglyceride (TG) turnover. To understand the lipolytic mechanism, immunoblotting and confocal image analyses of the T1AM-treated and control groups were conducted. The elevated lipolysis was accompanied by increases in the phosphorylation of adenosine monophosphate-activated protein kinase (p-AMPK), nuclear localization of forkhead box O1 (FoxO1), and expression of monoacylglycerol lipase (MGL) protein (P < 0.05). Finally, the treated cells exhibited downregulated expression of acetyl-CoA carboxylase (ACC) relative to p-ACC and increased protein expression of carnitine palmitoyltransferase 1 (CPT1) (P < 0.05). Taken together, T1AM showed lipolytic potency via activation of the AMPK/FoxO1/ATGL/MGL axis for decomposing TGs to FFAs and glycerol and of the AMPK/ACC/CPT1 pathway in facilitating the mobilization of FFAs into the mitochondria, highlighting its therapeutic potential for the treatment of obesity.

Abstract 6673: B7-H3-targeted 4-1BB activation potentiates CD8 T cell-dependent antitumor immunity without systemic toxicity

4-1BB is a costimulatory receptor on activated T and NK cells, and the stimulation of 4-1BB by the natural ligand or agonistic mAb enhances cellular proliferation and effector functions. Immunotherapy targeting 4-1BB has been tested for cancer patients; however, dose-limiting toxicities of 4-1BB agonists restrict further clinical development. B7-H3 (CD276) is overexpressed on the cell surface of multiple cancers and tumor-associated endothelial cells, yet barely on healthy adult tissues. To restrict 4-1BB stimulation activity in tumors, we have developed an FcγR-binding null bispecific IgG1 antibody consisting of B7-H3-targeting IgG and two anti-4-1BB single-chain variable fragments. The B7-H3x4-1BB bispecific antibody (B5x1D8) shows a potent in vitro T cell costimulatory activity in the presence of B7-H3 on the tumor cells. B5x1D8 rapidly accumulates in B7-H3-overexpressing tumors compared to 4-1BB agonistic mAb. B5x1D8 elicits a 4-1BB-dependent anti-tumor response in three different B7-H3-overexpressing murine tumor models. More importantly, in contrast to 4-1BB mAb, B5x1D8 does not induce any observable systemic abnormalities. Treatment of B5x1D8 increases the density, cytokine production, and proliferation of CD8 T cells in the tumor. Characterization of TILs indicates that B5x1D8 increases the number of PD-1+TIM-3+ “terminal effector” CD8 T cells for eliminating tumor cells. Furthermore, a combination of B5x1D8 and immune checkpoint blockade (ICB), anti-PD1, synergistically inhibits tumor growth. The human 4-1BB-targeting bispecific antibody also induces B7-H3-dependent 4-1BB costimulation and inhibits tumor growth in human 4-1BB transgenic mice. In sum, our data suggest that the B7-H3x4-1BB bispecific antibody represents an alternative form of IgG-based 4-1BB agonistic mAb for effective and safe cancer immunotherapy against B7-H3 positive cancers as monotherapy and combination therapy with other immunotherapy, like ICB.

Citation Format: Gihoon You, Yangsoon Lee, Yeon-Woo Kang, Han Wook Park, Kyeongsu Park, Jaeho Jung, Seung-Woo Lee. B7-H3-targeted 4-1BB activation potentiates CD8 T cell-dependent antitumor immunity without systemic toxicity [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6673.

Abstract 6524: A novel HER2/4-1BB bispecific antibody, YH32367 (ABL105) shows potent anti-tumor effect through tumor-directed T cell activation

4-1BB (TNFSF9, CD137) is a member of the tumor necrosis factor receptor superfamily that functions as a potent costimulator to immune cells, especially T-cell. Although current 4-1BB-targeted strong agonistic antibody exhibit a considerable anti-tumor effect through T cell activation, it has a limitation of liver toxicity. To overcome the challenges of targeting the 4-1BB, we developed a bispecific antibody that can induce tumor-directed T cell activation.

A novel HER2/4-1BB bispecific antibody, YH32367 (ABL105) targets human epidermal growth factor receptor 2 (HER2) and 4-1BB simultaneously and binds to both targets with high affinity. YH32367 (ABL105) exhibited a strong activation of 4-1BB signal in tumor cells expressing HER2 such as NCI-N87, BT474 and HCC1954 cell lines. In co-culture assay using human peripheral blood mononuclear cell (hPBMC) and HER2-expressing tumor cells, YH32367 (ABL105) stimulated IFN-γ secretion from hPBMC and thereby induced tumor cell lysis. The anti-tumor efficacy of YH32367 (ABL105) was evaluated in HCC1954-bearing hPBMC engrafted humanized mice and MC38/hHER2-bearing h4-1BB knock-in mice. YH32367 (ABL105) had more potent efficacy on tumor growth inhibition in both mouse models compared to the equimolar dosing of trastuzumab. Peripheral T cell increase was not observed in these studies. In particular, YH32367 (ABL105) showed a tumor regression in MC38/hHER2-bearing h4-1BB knock-in mice.

In conclusion, YH32367 (ABL105) significantly inhibited tumor growth in a HER2 expression dependent manner and showed potent in vivo efficacy through tumor-directed T cell activation without non-specific systemic T-cell activation.

Citation Format: Moo Young Song, Eun-Jung Lee, Hyejin Chung, Yangsoon Lee, Young Bong Park, Min Hyeok Jee, KyeongBae Kim, Mikyeong Ju, Jun Kyung Lee, Byung Hyun Choi, Ju Young Park, DaeWon Kim, Junhwan Kim, Sujin Ahn, Kyoung Kyu Ahn, Kyeongsu Park, Uijung Jung, Wonjun Son, Jaehyun Eom, Eunjung Kim, Donghoon Yeom, Jinhyung Ahn, Daehae Song, Byungje Sung, Weon-kyoo You, Jong Gyun Kim, Se-Woong Oh, Jaeho Jung. A novel HER2/4-1BB bispecific antibody, YH32367 (ABL105) shows potent anti-tumor effect through tumor-directed T cell activation [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6524.

Precision measurement of the neutral pion lifetime

The explicit breaking of the axial symmetry by quantum fluctuations gives rise to the so-called axial anomaly. This phenomenon is solely responsible for the decay of the neutral pion π⁰ into two photons (γγ), leading to its unusually short lifetime. We precisely measured the decay width Γ of the [Formula: see text] process. The differential cross sections for π⁰ photoproduction at forward angles were measured on two targets, carbon-12 and silicon-28, yielding [Formula: see text], where stat. denotes the statistical uncertainty and syst. the systematic uncertainty. We combined the results of this and an earlier experiment to generate a weighted average of [Formula: see text] Our final result has a total uncertainty of 1.50% and confirms the prediction based on the chiral anomaly in quantum chromodynamics.

Randomized phase III study of docetaxel plus bavituximab in previously treated advanced non-squamous non-small-cell lung cancer

Background

Bavituximab is a monoclonal antibody that targets phosphatidylserine in the presence of β2 glycoprotein 1 (β2GP1) to exert an antitumor immune response. This phase III trial determined the efficacy of bavituximab combined with docetaxel in patients with previously treated advanced non-small-cell lung cancer (NSCLC).

Patients and methods

Key eligibility criteria included advanced non-squamous NSCLC with disease progression after treatment with platinum-based doublet chemotherapy, evidence of disease control after at least two cycles of first-line therapy, presence of measurable disease, ECOG performance status 0 or 1, adequate bone marrow and organ function, and no recent history of clinically significant bleeding. Eligible patients were randomized 1 : 1 to receive up to six 21-day cycles of docetaxel plus either weekly bavituximab 3 mg/kg or placebo until progression or toxicity. The primary end point was overall survival (OS).

Results

A total of 597 patients were enrolled. Median OS was 10.5 months in the docetaxel + bavituximab arm and was 10.9 months in the docetaxel + placebo arm (HR 1.06; 95% CI 0.88-1.29; P = 0.533). There was no difference in progression-free survival (HR 1.00; 95% CI 0.82-1.22; P = 0.990). Toxicities were manageable and similar between arms. In subset analysis, among patients with high baseline serum β2GP1 levels ≥200 µg/ml, a nonsignificant OS trend favored the bavituximab arm (HR 0.82; 95% CI 0.63-1.06; P = 0.134). Among patients who received post-study immune checkpoint inhibitor therapy, OS favored the bavituximab arm (HR 0.46; 95% CI 0.26-0.81; P = 0.006).

Conclusions

The combination of bavituximab plus docetaxel is not superior to docetaxel in patients with previously treated advanced NSCLC. The addition of bavituximab to docetaxel does not meaningfully increase toxicity. The potential benefit of bavituximab observed in patients with high β2GP1 levels and in patients subsequently treated with immune checkpoint inhibitors requires further investigation.

Clinical trial number

NCT01999673.