Background: Cancer patients are regarded as a highly vulnerable group in the current Coronavirus Disease 2019 (COVID-19) pandemic. To date, the clinical characteristics of COVID-19-infected cancer patients remain largely unknown. Patients and methods: In this retrospective cohort study, we included cancer patients with laboratory-confirmed COVID-19 from three designated hospitals in Wuhan, China. Clinical data were collected from medical records from 13 January 2020 to 26 February 2020. Univariate and multivariate analyses were carried out to assess the risk factors associated with severe events defined as a condition requiring admission to an intensive care unit, the use of mechanical ventilation, or death. Results: A total of 28 COVID-19-infected cancer patients were included; 17 (60.7%) patients were male. Median (interquartile range) age was 65.0 (56.0e70.0) years. Lung cancer was the most frequent cancer type (n ¼ 7; 25.0%). Eight (28.6%) patients were suspected to have hospital-associated transmission. The following clinical features were shown in our cohort: fever (n ¼ 23, 82.1%), dry cough (n ¼ 22, 81%), and dyspnoea (n ¼ 14, 50.0%), along with lymphopaenia (n ¼ 23, 82.1%), high level of high-sensitivity C-reactive protein (n ¼ 23, 82.1%), anaemia (n ¼ 21, 75.0%), and hypoproteinaemia (n ¼ 25, 89.3%). The common chest computed tomography (CT) findings were ground-glass opacity (n ¼ 21, 75.0%) and patchy consolidation (n ¼ 13, 46.3%). A total of 15 (53.6%) patients had severe events and the mortality rate was 28.6%. If the last antitumour treatment was within 14 days, it significantly increased the risk of developing severe events [hazard ratio (HR) ¼ 4.079, 95% confidence interval (CI) 1.086e15.322, P ¼ 0.037]. Furthermore, patchy consolidation on CT on admission was associated with a higher risk of developing severe events (HR ¼ 5.438, 95% CI 1.498e19.748, P ¼ 0.010). Conclusions: Cancer patients show deteriorating conditions and poor outcomes from the COVID-19 infection. It is recommended that cancer patients receiving antitumour treatments should have vigorous screening for COVID-19 infection and should avoid treatments causing immunosuppression or have their dosages decreased in case of COVID-19 coinfection.

Cancer stem cell (CSC), the primary source of cancer-initiating population, is involved in cancer recurrence and drug-resistant phenotypes. This study demonstrates that the loss of DAB2IP, a novel Ras-GTPase activating protein frequently found in many cancer types, is associated with CSC properties. Mechanistically, DAB2IP is able to suppress stem cell factor receptor (c-kit or CD117) gene expression by interacting with a newly identified silencer in the c-kit gene. Moreover, DAB2IP is able to inhibit c-kit-PI3K-Akt-mTOR signaling pathway that increases c-myc protein to activate ZEB1 gene expression leading to the elevated CSC phenotypes. An inverse correlation between CD117 or ZEB1 and DAB2IP is also found in clinical specimens. Similarly, Elevated expression of ZEB1 and CD117 are found in the prostate basal cell population of DAB2IP knockout mice. Our study reveals that DAB2IP has a critical role in modulating CSC properties via CD117-mediated ZEB1 signaling pathway.

The macroscopic tunneling of an optomechanical membrane is considered. A cavity mode which couples quadratically to the membranes position can create highly tunable adiabatic double-well potentials, which together with the high Q-factors of such membranes render the observation of macroscopic tunneling possible. A suitable, pulsed measurement scheme using a linearly coupled mode of the cavity for the verification of the effect is studied.PACS numbers: 03.65. Xp,81.07.Oj, Optomechanical systems have seen a recent surge in experimental and theoretical interest, culminating in the cooling of micromechanical oscillators to within a fraction of a phonon of their quantum ground state [1][2][3][4] and the reaching of the strong coupling between cavity field and mechanical element [5][6][7]. Despite these successes, few experimental demonstrations of their non-classical behavior have been achieved so far. Notable exceptions include Ref.[1], which coupled the mechanical oscillator to a Josephson qubit to detect the presence of a single mechanical phonon, and Ref. [4], which demonstrated the asymmetry between up-converted and down-converted photons of a probe laser field, an unambiguous signature of the asymmetry between phonon absorption and emission. Additional proposals to generate and exploit nonclassical effects in cavity optomechanics include schemes to squeeze a motional quadrature of the oscillator [8][9][10][11][12][13], perform quantum state tomography [1,14,15], or offer alternative ways to engineer non-classical mechanical states [16,17] including most intriguingly perhaps the realization of Schrödinger cat states in truly macroscopic systems [18][19][20].This paper extends these considerations by exploring the possibility to realize and monitor the quantum tunneling of an optomechanical system operating deep in the quantum regime through a classically forbidden potential barrier. The observation of the tunneling of such a truly macroscopic object has not been achieved yet, although theoretical proposals have been made [21]. We find that this can be achieved in a "membrane-in-themiddle" (MiM) configuration [22,23] under conditions that are close to being realizable in current state-of-theart experiments. We propose a detection scheme based on pulsed optomechanics ideas [15] that permits to monitor the tunneling dynamics through a series of weak measurements of the membrane position.Our approach relies on adiabatically raising a potential barrier, whose parameters can be widely tuned, at the location of a mechanical harmonic oscillator. We show that the ground state of the resulting double-well potential can exhibit tunneling rates several orders of magnitude larger than the decoherence rate of the mechanical mem- brane, and that a weak optomechanical position measurement is enough to monitor the tunneling. Besides tunneling, the proposed scheme allows for the study of the quantum Zeno effect [24] in a mechanical context and provides a comparatively simple scheme for the preparation and characterization of non-...