Azimuthal Anisotropy of Heavy-Flavor Decay Electrons in p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

Angular correlations between heavy-flavor decay electrons and charged particles at midrapidity (|η|<0.8) are measured in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. The analysis is carried out for the 0%-20% (high) and 60%-100% (low) multiplicity ranges. The jet contribution in the correlation distribution from high-multiplicity events is removed by subtracting the distribution from low-multiplicity events. An azimuthal modulation remains after removing the jet contribution, similar to previous observations in two-particle angular correlation measurements for light-flavor hadrons. A Fourier decomposition of the modulation results in a positive second-order coefficient (v_{2}) for heavy-flavor decay electrons in the transverse momentum interval 1.5<p_{T}<4  GeV/c in high-multiplicity events, with a significance larger than 5σ. The results are compared with those of charged particles at midrapidity and those of inclusive muons at forward rapidity. The v_{2} measurement of open heavy-flavor particles at midrapidity in small collision systems could provide crucial information to help interpret the anisotropies observed in such systems.

A case of nivolumab-induced acute-onset type 1 diabetes mellitus in melanoma

Nivolumab, an anti-PD-1 antibody, is now considered an important therapeutic agent in several advanced malignancies. However, immune-related adverse events such as endocrinopathies have been reported with its use. Thyroid disorder and isolated adrenocorticotropic hormone deficiency have frequently been reported as nivolumab-induced immune-related adverse events. Another endocrinopathy is nivolumab-induced type 1 diabetes mellitus (t1dm), described as diabetes mellitus with rapid onset and complete insulin insufficiency, at times leading to fulminant t1dm. We report the case of a 68-year-old woman who developed pancreatic islet-related autoantibody-negative t1dm, possibly induced by nivolumab, under continuous glucocorticoid administration. She was treated with nivolumab for advanced malignant melanoma, concomitant with 10 mg prednisolone daily for thrombophlebitis tapered to 5 mg after 13 courses of nivolumab therapy. At approximately the 27th course of nivolumab therapy, she showed elevated plasma glucose levels despite preserved insulin secretion. A month later, she developed diabetic ketoacidosis. Her insulin secretion decreased and finally was exhausted. She was diagnosed with acute-onset rather than fulminant t1dm because of a rapidly progressive course to diabetic ketoacidosis during just more than 1 week. She is currently receiving insulin replacement. There has been no recurrence of the melanoma. Thus, nivolumab might induce autoimmune diabetes mellitus, with patients having t1dm-sensitive human leucocyte antigen being more susceptible even when receiving glucocorticoids. Physicians should be aware that nivolumab could potentially induce t1dm as a critical immune-related adverse event.

Tumor-Specific S/G2-Phase Cell Cycle Arrest of Cancer Cells by Methionine Restriction

Cancer cells require elevated amounts of methionine (MET) and arrest their growth under conditions of MET restriction (MR). This phenomenon is termed MET dependence. Fluorescence-activated cell sorting (FACS) first indicated that the MET-dependent SV40-transformed cancer cells were arrested in the S and G₂ phases of the cell cycle when under MR. This is in contrast to a G₁-phase accumulation of cells, which occurs only in MET-supplemented medium at very high cell densities and which is similar to the G₁ cell-cycle block which occurs in cultures of normal fibroblasts at high density. When the human PC-3 prostate carcinoma cell line was cultured in MET-free, homocysteine-containing (MET^-HCY⁺) medium, there was an extreme increment in DNA content without cell division indicating that the cells were blocked in S phase. Recombinant methioninase (rMETase) treatment of cancer cells also selectively trapped cancer cells in S/G₂: The cell cycle phase of the cancer cells was visualized with the fluorescence ubiquitination cell cycle indicator (FUCCI). At the time of rMETase-induced S/G₂-phase trap, identified by the cancer cells' green fluorescence by FUCCI imaging, the cancer cells were administered S-phase-dependent chemotherapy drugs, which interact with DNA or block DNA synthesis such as doxorubicin, cisplatin, or 5-fluorouracil (5-FU) and which were highly effective in killing the cancer cells. In contrast, treatment of cancer cells with drugs in the presence of MET, only led to the majority of the cancer cell population being blocked in G₀/G₁ phase, identified by the cancer cells becoming red fluorescent in the FUCCI system. The G₀/G₁ blocked cells were resistant to the chemotherapy. MR has the potential for highly effective cell-cycle-based treatment strategy for cancer in the clinic.

Activation of AZIN1 RNA editing is a novel mechanism that promotes invasive potential of cancer-associated fibroblasts in colorectal cancer

Adenosine-to-inosine (A-to-I) RNA editing is a recently described epigenetic modification, which is believed to constitute a key oncogenic mechanism in human cancers. However, its functional role in cancer-associated fibroblasts (CAFs) within the tumor microenvironment (TME) and its clinical significance remains unclear. Herein, we systematically analyzed a large cohort of 627 colorectal cancer (CRC) specimens, and investigated the expression pattern of ADAR1 and its biological significance on the antizyme inhibitor 1 (AZIN1) RNA editing levels. Both ADAR1 expression and AZIN1 RNA editing levels were significantly elevated in CRC tissues vs. normal mucosa, and these findings correlated with the increased expression of mesenchymal markers, Vimentin (ρ = 0.44) and Fibroblast activation protein (ρ = 0.38). Intriguingly, ADAR1 expression was specifically upregulated in both cancer cells and fibroblasts from cancerous lesions. Conditioned medium from cancer cells led to induction of ADAR1 expression and activation of AZIN1 RNA editing in fibroblasts (p < 0.05). Additionally, edited AZIN1 enhanced the invasive potential of fibroblasts. In conclusion, we provide novel evidence that hyper-editing of AZIN1 enhances the invasive potential of CAFs within the TME in colon and is an important predictor of tumor invasiveness in CRC.

Abstract 1101: Visualization of epithelial-mesenchymal transition in inflammatory microenvironment-colorectal cancer network in vitro and in vivo

Background: Epithelial-mesenchymal transition (EMT) is a biologic process by which epithelial cancer cells acquire mesenchymal phenotype with malignant properties for invasion and metastasis, leading to poor prognosis. Inflammatory microenvironment has been shown to be responsible for the development and progression of colorectal cancer (CRC). However, the precise role of inflammatory microenvironment in the EMT-related tumor progression remains unclear because EMT network is regulated by complex crosstalk between tumor and normal cells. In this study, we developed a fluorescence-guided live-cell imaging system for the spatiotemporal visualization of EMT state, and assessed the in vitro and in vivo visualization of EMT state in human CRC cells under the inflammatory microenvironment.

Methods: We used two human CRC cell lines, HCT116 and RKO. The promoter of mesenchymal marker vimentin was used for inducing the EMT-dependent red fluorescence protein (RFP) expression in human CRC cells. The RFP expression was quantitatively analyzed to evaluate its association with EMT-related markers and malignant phenotype. Inflammatory cytokines, IL-1β (1 ng/ml) and TNF-α (20 ng/ml), or co-culture with inflammatory mouse macrophage cell line RAW264.7 stimulated by lipopolysaccharide (LPS) (200 ng/mL) were used as an inflammatory microenvironment. Biodistribution of EMT cells was analyzed using in vivo experiments with primary and metastatic CRC xenograft tumors.

Results: Inflammatory cytokines reversely induced the RFP expression in association with EMT-related malignant phenotype, such as morphologic change, EMT marker modulation, and invasion ability, in HCT116 and RKO cells. Co-culture with LPS-stimulated inflammatory macrophages also induced the RFP expression by secreting inflammatory cytokines. In vivo experiments revealed that EMT cells were detected within tumor tissues at colon, liver and peritoneum.

Conclusions: Our results suggest that inflammatory microenvironment has a great potential to induce EMT program in CRC cells. This fluorescence-guided EMT imaging system is a useful tool for monitoring the EMT state in the inflammation microenvironment-CRC network in vitro and in vivo.

Citation Format: Hiroshi Tazawa, Takeshi Ieda, Shuya Yano, Satoru Kikuchi, Shinji Kuroda, Toshiaki Ohara, Kazuhiro Noma, Hiroyuki Kishimoto, Masahiko Nishizaki, Shunsuke Kagawa, Takashi Saitou, Takeshi Imamura, Toshiyoshi Fujiwara. Visualization of epithelial-mesenchymal transition in inflammatory microenvironment-colorectal cancer network in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1101.

A Case of T-Cell Lymphoma Accompanying Marked Eosinophilia, Chronic Eosinophilic Pneumonia and Eosinophilic Pleural Effusion. A Case Report

A 57-year-old woman was admitted to our hospital for lumbago, weight loss and weakness of her right lower extremity. Leukocytosis was evident with marked eosinophilia (65.5 % = 46,000/mm3), and the chest roentgenogram showed diffuse reticular shadows throughout both lung fields and a left pleural effusion. The pleural effusion contained 22.4 % eosinophils with no immature cells. Biopsy of a thumb-sized mass on the chest wall revealed a T-cell lymphoma of pleomorphic type. The diffuse pulmonary shadow was diagnosed as chronic eosinophilic pneumonia by autopsy. This was a relatively rare case of T-cell lymphoma, in which an eosinophilic pneumonia and eosinophilic pleural effusion were observed.

D-Meson Azimuthal Anisotropy in Midcentral Pb-Pb Collisions at sqrt[s]_{NN}=5.02 TeV

The azimuthal anisotropy coefficient v_{2} of prompt D^{0}, D^{+}, D^{*+}, and D_{s}^{+} mesons was measured in midcentral (30%-50% centrality class) Pb-Pb collisions at a center-of-mass energy per nucleon pair sqrt[s_{NN}]=5.02  TeV, with the ALICE detector at the LHC. The D mesons were reconstructed via their hadronic decays at midrapidity, |y|<0.8, in the transverse momentum interval 1<p_{T}<24  GeV/c. The measured D-meson v_{2} has similar values as that of charged pions. The D_{s}^{+} v_{2}, measured for the first time, is found to be compatible with that of nonstrange D mesons. The measurements are compared with theoretical calculations of charm-quark transport in a hydrodynamically expanding medium and have the potential to constrain medium parameters.

Fluorescence-guided surgery of a highly-metastatic variant of human triple-negative breast cancer targeted with a cancer-specific GFP adenovirus prevents recurrence

We have previously developed a genetically-engineered GFP-expressing telomerase-dependent adenovirus, OBP-401, which can selectively illuminate cancer cells. In the present report, we demonstrate that targeting a triple-negative high-invasive human breast cancer, orthotopically-growing in nude mice, with OBP-401 enables curative fluorescence-guided surgery (FGS). OBP-401 enabled complete resection and prevented local recurrence and greatly inhibited lymph-node metastasis due to the ability of the virus to selectively label and subsequently kill cancer cells. In contrast, residual breast cancer cells become more aggressive after bright (white)-light surgery (BLS). OBP-401-based FGS also improved the overall survival compared with conventional BLS. Thus, metastasis from a highly-aggressive triple-negative breast cancer can be prevented by FGS in a clinically-relevant mouse model.

Tumor-targeting adenovirus OBP-401 inhibits primary and metastatic tumor growth of triple-negative breast cancer in orthotopic nude-mouse models

Our laboratory previously developed a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of the human MDA-MB-231 cell line in nude mice. The isolated variant was highly-invasive in the mammary gland and lymphatic channels and metastasized to lymph nodes in 10 of 12 mice compared to 2 of 12 of the parental cell line. In the present study, the tumor-selective telomerase dependent OBP-401 adenovirus was injected intratumorally (i.t.) (1 × 10⁸ PFU) when the high-metastatic MDA-MB-231 primary tumor expressing red fluorescent protein (MDA-MB-231-RFP) reached approximately 500 mm³ (diameter; 10 mm). The mock-infected orthotopic primary tumor grew rapidly. After i.t. OBP-401 injection, the growth of the orthotopic tumors was arrested. Six weeks after implantation, the fluorescent area and fluorescence intensity showed no increase from the beginning of treatment. OBP-401 was then injected into high-metastatic MDA-MB-231-RFP primary orthotopic tumor growing in mice which already had developed metastasis within lymphatic ducts. All 7 of 7 control mice subsequently developed lymph node metastasis. In contrast, none of 7 mice which received OBP-401 had lymph node metastasis. Seven of 7 control mice also had gross lung metastasis. In contrast, none of the 7 mice which received OBP-401 had gross lung metastasis. Confocal laser microscopy imaging demonstrated that all control mice had diffuse lung metastases. In contrast, all 7 mice which received OBP-401 only had a few metastatic cells in the lung. OBP-401 treatment significantly extended survival of the treated mice.

Spin-Glass Ground State in a Triangular-Lattice Compound YbZnGaO_{4}

We report on comprehensive results identifying the ground state of a triangular-lattice structured YbZnGaO_{4} as a spin glass, including no long-range magnetic order, prominent broad excitation continua, and the absence of magnetic thermal conductivity. More crucially, from the ultralow-temperature ac susceptibility measurements, we unambiguously observe frequency-dependent peaks around 0.1 K, indicating the spin-glass ground state. We suggest this conclusion holds also for its sister compound YbMgGaO_{4}, which is confirmed by the observation of spin freezing at low temperatures. We consider disorder and frustration to be the main driving force for the spin-glass phase.

J/ψ Elliptic Flow in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

We report a precise measurement of the J/ψ elliptic flow in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The J/ψ mesons are reconstructed at midrapidity (|y|<0.9) in the dielectron decay channel and at forward rapidity (2.5<y<4.0) in the dimuon channel, both down to zero transverse momentum. At forward rapidity, the elliptic flow v_{2} of the J/ψ is studied as a function of the transverse momentum and centrality. A positive v_{2} is observed in the transverse momentum range 2<p_{T}<8  GeV/c in the three centrality classes studied and confirms with higher statistics our earlier results at sqrt[s_{NN}]=2.76  TeV in semicentral collisions. At midrapidity, the J/ψ  v_{2} is investigated as a function of the transverse momentum in semicentral collisions and found to be in agreement with the measurements at forward rapidity. These results are compared to transport model calculations. The comparison supports the idea that at low p_{T} the elliptic flow of the J/ψ originates from the thermalization of charm quarks in the deconfined medium but suggests that additional mechanisms might be missing in the models.

Anomalous Evolution of the Near-Side Jet Peak Shape in Pb-Pb Collisions at sqrt[s_{NN}]=2.76 TeV

The measurement of two-particle angular correlations is a powerful tool to study jet quenching in a p_{T} region inaccessible by direct jet identification. In these measurements pseudorapidity (Δη) and azimuthal (Δφ) differences are used to extract the shape of the near-side peak formed by particles associated with a higher p_{T} trigger particle (1<p_{T,trig}<8  GeV/c). A combined fit of the near-side peak and long-range correlations is applied to the data allowing the extraction of the centrality evolution of the peak shape in Pb-Pb collisions at sqrt[s_{NN}]=2.76  TeV. A significant broadening of the peak in the Δη direction at low p_{T} is found from peripheral to central collisions, which vanishes above 4  GeV/c, while in the Δφ direction the peak is almost independent of centrality. For the 10% most central collisions and 1<p_{T,assoc}<2  GeV/c, 1<p_{T,trig}<3  GeV/c a novel feature is observed: a depletion develops around the center of the peak. The results are compared to pp collisions at the same center of mass energy and ampt model simulations. The comparison to the investigated models suggests that the broadening and the development of the depletion is connected to the strength of radial and longitudinal flow.