Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts

It has been shown that arsenic trioxide (ATO) induced apoptosis in human nasopharyngeal carcinoma cells and inhibited the growth of nasopharyngeal carcinoma xenografts (NPCX) in nude mice. Aim: The present study was designed to determine whether ATO at the non-toxic dose level could potentiate the therapeutic effectiveness of radiation therapy in nasopharyngeal carcinoma, using a BALB/C nude mouse xenograft model. Methods: The mice bearing NPCX were treated with radiation alone (2, 4, and 6 Gy), ATO alone (4 mg/kg/day x 6 days), and ATO plus radiation at the same dosage levels. Time of tumor growth delay (defined as the time necessary for the tumor to grow four-fold of its initial volume after, compared with untreated tumors) and toxic effects were determined. Results: The low dose ATO alone has no pronounced effects on tumor growth delay compared to untreated control. However, compared with radiation alone, the combined regimen delayed the tumor growth by 2–10 days and had no significant toxic effects such as the liver function damage. Conclusions: Combination of ATO at non-toxic dose level and radiation has synergistic effects on tumor growth inhibition in vivo and is well tolerated.Установлено, что триоксид мышьяка (ТОМ) индуцирует апоптоз в клетках карциномы носоглотки человека и ингибирует рост ксенографта карциномы носоглотки у атимических мышей. Цель работы — установить терапевтическую эффективность радиотерапии в комбинации ТОМ в нетоксичной дозе мышам линии BALB/ с ксенографтом карциномы носоглотки. Методы: животные с ксенографтом карциномы носоглотки получали либо только радиотерапию (2, 4 и 6 Гр) или ТОМ (4 мг/кг/день в течение 6 дней), или их комбинацию в тех же режимах и дозах. Задержку роста опухоли определяли как различие во времени, необходимом для достижения опухолью 4-кратного объема по сравнению с начальным объемом в опытной группе versus такового в контрольной группе. Результаты: введение ТОМ в низкой дозе не оказывало выраженного влияния на рост опухоли по сравнению с показателями в конт­рольной группе, а в комбинации с облучением приводило к задержке роста опухоли на 2–12 сут по сравнению с показателями у животных, получавших только лучевую терапию при отсутствии выраженных побочных эффектов. Выводы: комбинация ТОМ в нетоксической дозе и лучевой терапии приводит к ингибированию роста опухоли in vivo и не вызывает побочных эффектов. Ключевые слова: триоксид мышьяка, радиотерапия, ксенографт карциномы носоглотки

Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation

The current status of electric dipole moments of diamagnetic atoms which involves the synergy between atomic experiments and three different theoretical areas -- particle, nuclear and atomic is reviewed. Various models of particle physics that predict CP violation, which is necessary for the existence of such electric dipole moments, are presented. These include the standard model of particle physics and various extensions of it. Effective hadron level combined charge conjugation (C) and parity (P) symmetry violating interactions are derived taking into consideration different ways in which a nucleon interacts with other nucleons as well as with electrons. Nuclear structure calculations of the CP-odd nuclear Schiff moment are discussed using the shell model and other theoretical approaches. Results of the calculations of atomic electric dipole moments due to the interaction of the nuclear Schiff moment with the electrons and the P and time-reversal (T) symmetry violating tensor-pseudotensor electron-nucleus are elucidated using different relativistic many-body theories. The principles of the measurement of the electric dipole moments of diamagnetic atoms are outlined. Upper limits for the nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained combining the results of atomic experiments and relativistic many-body theories. The coefficients for the different sources of CP violation have been estimated at the elementary particle level for all the diamagnetic atoms of current experimental interest and their implications for physics beyond the standard model is discussed. Possible improvements of the current results of the measurements as well as quantum chromodynamics, nuclear and atomic calculations are suggested.Comment: 46 pages, 19 tables and 16 figures. A review article accepted for EPJ

Search for jet extinction in the inclusive jet-pT spectrum from proton-proton collisions at s=8 TeV

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.The first search at the LHC for the extinction of QCD jet production is presented, using data collected with the CMS detector corresponding to an integrated luminosity of 10.7  fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The extinction model studied in this analysis is motivated by the search for signatures of strong gravity at the TeV scale (terascale gravity) and assumes the existence of string couplings in the strong-coupling limit. In this limit, the string model predicts the suppression of all high-transverse-momentum standard model processes, including jet production, beyond a certain energy scale. To test this prediction, the measured transverse-momentum spectrum is compared to the theoretical prediction of the standard model. No significant deficit of events is found at high transverse momentum. A 95% confidence level lower limit of 3.3 TeV is set on the extinction mass scale

Searches for electroweak neutralino and chargino production in channels with Higgs, Z, and W bosons in pp collisions at 8 TeV

Searches for supersymmetry (SUSY) are presented based on the electroweak pair production of neutralinos and charginos, leading to decay channels with Higgs, Z, and W bosons and undetected lightest SUSY particles (LSPs). The data sample corresponds to an integrated luminosity of about 19.5 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV collected in 2012 with the CMS detector at the LHC. The main emphasis is neutralino pair production in which each neutralino decays either to a Higgs boson (h) and an LSP or to a Z boson and an LSP, leading to hh, hZ, and ZZ states with missing transverse energy (E-T(miss)). A second aspect is chargino-neutralino pair production, leading to hW states with E-T(miss). The decays of a Higgs boson to a bottom-quark pair, to a photon pair, and to final states with leptons are considered in conjunction with hadronic and leptonic decay modes of the Z and W bosons. No evidence is found for supersymmetric particles, and 95% confidence level upper limits are evaluated for the respective pair production cross sections and for neutralino and chargino mass values

Arsenic trioxide reduces the invasive and metastatic properties of nasopharyngeal carcinoma cells in vitro

Nasopharyngeal carcinoma (NPC) is notorious for the metastases, which are in close association with Epstein-Barr virus-encoded latent membrane protein 1 (LMP1). Arsenic trioxide (As2O3) has been shown to induce apoptosis and differentiation in NPC xenografts. Then, can it repress the cancer cells' metastasis potential? To elucidate this issue, the present study was performed. LMP1-negative cell line HNE1 and LMP1-positive cell line HNE1-LMP1 were used as in vitro model. Cells (1 x 10(5)/mL) were cultured with or without 3 µM As2O3 for 48 h. Then the survival cells were collected to investigate their potential of colony formation, attachment, invasion, and migration. Both confocal immunofluorescence staining and Western blot were used to detect the changes of LMP1 expression. The changes of MMP-9 were examined by RT-PCR assay and Western blot. The results were as follow: i) the colony formation inhibition rate (75.41 ± 3.9% in HNE1-LMP1 cells vs 37.89 ± 4.9% in HNE1 cells), the rate of attachment (HNE1-LMP1 vs HNE1: 56.40 ± 3.5 vs 65.87 ± 5.9%), the invasion inhibitory rate (HNE1-LMP1 vs HNE1: 56.50 ± 3.7 and 27.91 ± 2.1%), and the migration inhibitory rate (HNE1-LMP1 vs HNE1: 48.70 ± 3.9 vs 29.19 ± 6.27%) were all significantly different between the two cell lines (P < 0.01). ii) LMP1 was down-regulated in As2O3-treated HNE1-LMP1 cells. iii) The reduction of MMP-9 was found in As2O3-treated groups, more evident in HNE1-LMP1 cells. Thus, we conclude that As2O3 can reduce metastasis potential of NPC cells, involving inhibition of MMP-9 expression. LMP1 were also reduced in this process and seemed to enhance anti-metastasis activity of As2O3