The novel COVID-19 outbreak has affected more than 200 countries and territories as of March 2020. Given that patients with cancer are generally more vulnerable to infections, systematic analysis of diverse cohorts of patients with cancer affected by COVID-19 is needed. We performed a multicenter study including 105 patients with cancer and 536 age-matched noncancer patients confirmed with COVID-19. Our results showed COVID-19 patients with cancer had higher risks in all severe outcomes. Patients with hematologic cancer, lung cancer, or with metastatic cancer (stage IV) had the highest frequency of severe events. Patients with nonmetastatic cancer experienced similar frequencies of severe conditions to those observed in patients without cancer. Patients who received surgery had higher risks of having severe events, whereas patients who underwent only radiotherapy did not demonstrate significant differences in severe events when compared with patients without cancer. These findings indicate that patients with cancer appear more vulnerable to SARS-COV-2 outbreak.SIgnIfICAnCe: Because this is the first large cohort study on this topic, our report will provide muchneeded information that will benefit patients with cancer globally. As such, we believe it is extremely important that our study be disseminated widely to alert clinicians and patients.

No abstract

BackgroundEpigenetic silencing of tumor suppressor genes associated with promoter methylation is considered to be a hallmark of oncogenesis. RASSF1A is a candidate tumor suppressor gene which was found to be inactivated in many human cancers. Although we have had a prelimilary cognition about the function of RASSF1A, the exact mechanisms about how RASSF1A functions in human cancers were largely unknown. Moreover, the effect of mutated K-Ras gene on the function of RASSF1A is lacking. The aim of this study was to investigate the expression profile and methylation status of RASSF1A gene, and to explore its concrete mechanisms as a tumor suppressor gene in Nasopharyngeal Carcinoma.MethodsWe examined the expression profile and methylation status of RASSF1A in two NPC cell lines, 38 primary nasopharyngeal carcinoma and 14 normal nasopharyngeal epithelia using RT-PCR and methylated specific PCR(MSP) respectively. 5-aza-dC was then added to confirm the correlation between hypermethylation status and inactivation of RASSF1A. The NPC cell line CNE-2 was transfected with exogenous pcDNA3.1(+)/RASSF1A plasmid in the presence or absence of mutated K-Ras by liposome-mediated gene transfer method. Flow cytometry was used to examine the effect of RASSF1A on cell cycle modulation and apoptosis. Meanwhile, trypan blue dye exclusion assays was used to detect the effect of RASSF1A transfection alone and the co-transfection of RASSF1A and K-Ras on cell proliferation.ResultsPromoter methylation of RASSF1A could be detected in 71.05% (27/38) of NPC samples, but not in normal nasopharyngeal epithelia. RASSF1A expression in NPC primary tumors was lower than that in normal nasopharyngeal epithelial (p < 0.01). Expression of RASSF1A was down-regulated in two NPC cell lines. Loss of RASSF1A expression was greatly restored by the methyltransferase inhibitor 5-aza-dC in CNE-2. Ectopic expression of RASSF1A in CNE-2 could increase the percentage of G0/G1 phase cells (p < 0.01), inhibit cell proliferation and induce apoptosis (p < 0.001). Moreover, activated K-Ras could enhance the growth inhibition effect induced by RASSF1A in CNE-2 cells (p < 0.01).ConclusionExpression of RASSF1A is down-regulated in NPC due to the hypermethylation of promoter. Exogenous expression of RASSF1A is able to induce growth inhibition effect and apoptosis in tumor cell lines, and this effect could be enhanced by activated K-Ras.

Abstract.Statins have been confirmed with protective effect to microvessels in diabetic retinopathy, implicated as reducing vascular permeability, maintaining endothelial junction integrity and improving blood perfusion, which are surrogate markers of vascular 'normalization', but no data are currently available on efficacy of statins on tumor endothelial functions. Since statins have been shown to exhibit a biphasic dose-related response on biological behaviour of microvessels, we sought to determine whether statins with bipolar concentrations can ameliorate vessel dysfunction and then increase efficiency of chemotherapeutics in Lewis lung carcinoma and B16F10 melanoma models. Our in vitro study showed that simvastatin reduces hypoxia-induced endothelium leakage in human umbilical vein endothelial cells (HUVEC) in a concentration-dependent manner. In tumor-bearing mice, low-dose simvastatin (0.2 mg/kg) induced upregulation of endothelial NO synthase (eNOS) skewed vessels to a pericyte-coated and stable pattern, while high-dose simvastatin (10 mg/kg) remarkably deceased reactive oxygen species (ROS)-induced hypoxia-inducible factor (HIF-1α) and vascular endothelial growth factor (VEGF) expression, attenuating VEGF-drived tumor vessel hyperpermeability. These changes ultimately improved intratumoral perfusion and decreased tumor hypoxia. Administration of cisplatin and cyclophosphamide to the simvastatin-treated mice resulted in slower tumor growth. Collectively, simvastatin may promote tumor vessel normalization and show clinical benefit when used in combination with chemotherapeutics. IntroductionPathological angiogenesis and abnormal vessel structures and functions are common features of solid tumors and several non-malignant diseases, such as schwannomas and diabetic retinopathy (DR) (1,2). Vessels in these lesions are highly disorganized and inefficient, and lack pericytes or normal attachment between pericytes and endothelial cells (ECs) (3-5). Such abnormalities of tumor vessels in turn lead to impairment of endothelial barrier function, decreased blood flow and subsequent aggravation of hypoxia in tumor tissues, which result in a poor delivery of anticancer therapeutics and augmentation of radioresistance in tumors. Similar vessel phenotypes are shown in DR characterized by breakdown of the blood-retinal barrier (BRB) that lead to diabetic macular edema and vision loss (6).By correcting the aberrance in morphological structure and function of vessels, we could normalize the microenvironment of retina in favor of disease control and improve response to other therapies (7,8). The strategies for vascular normalization are likely multifaceted. Substantial evidence indicates that anti-angiogenic treatment could achieve this goal by pharmacological inhibition of vascular endothelial growth factor (VEGF) signaling and it has become a widely accepted treatment for several diseases where neovascularization and permeability plays a pivotal role, including cancer and retinal disorders (8,9). Bevacizumab, a humanized...

Background NEK2, a serine/threonine kinase involved in mitosis, has been found to function in chromosome instability, tumor progression and metastasis, but its role in cervical cancer radioresistance remains unknown. Methods We detected the protein levels of NEK2 in cervical carcinoma tissues and paired paracarcinoma tissues by immunohistochemistry. The roles of NEK2 in oncogenesis were examined using cell growth and colony formation assays, EdU assay, apoptosis assay as well as in vivo mouse model. γ-H2AX and Rad51 foci formation, neutral comet assay and clonogenic cell survival assay were applied to determine the radiosensitivity of cervical cancer cells. RNA-seq was performed to identify the downstream effector of NEK2. The gene expression levels were measured by Real-time PCR. Results We report that NEK2 protein level is overexpressed and correlated with the tumor stage and lymph node metastasis in cervical cancer tissues. Furthermore, we provided evidence that depletion of NEK2 impairs oncogenesis and enhances radiosensitivity in cervical cancer. Using RNA sequencing, we identify Wnt1 as a key downstream effector of NEK2. Knockdown of NEK2 downregulates the mRNA and protein levels of Wnt1, thereby inhibiting the activation of the Wnt/β-catenin signaling pathway. More importantly, the observed consequences induced by NEK2 depletion in cervical cancer cells can be partially rescued by Wnt1 overexpression. Conclusions Our results demonstrate that NEK2 activates the Wnt/β-catenin signaling pathway via Wnt1 to drive oncogenesis and radioresistance in cervical cancer, indicating that NEK2 may be a promising target for the radiosensitization of cervical cancer.

The effects of Oxymatrine (Oxy) on the proliferation and apoptosis of human esophageal carcinoma Eca109 cell line and the mechanism were investigated. The human esophageal carcinoma Eca109 cells were cultured in vitro. The Oxy-induced apoptosis of Eca 109 cells was assayed by using flow cytometry. The expressions of p-ERK(1/2), Cyclin D1, p21(waf/cip1), Bax and Bcl-2 were detected by Western blot. Flow cytometry revealed that Oxy could induce the apoptosis of Eca109 cells. Western blot showed that Oxy of different concentrations suppressed the expressions of p-ERK(1/2), Cyclin D1 and Bcl-2, but up-regulated the expression of p21(waf/cip1) and Bax, and the ratio of Bax/Bcl-2 was increased. It was suggested the Oxy could induce the apoptosis of Eca109 cells, which might be related to the upregulation of p21(waf/cip1) and the downregulation of p-ERK(1/2), Cyclin D1 and p21(waf/cip1). The possible pathway may be related to Bcl-2/Bax.

Abstract.Patients with esophageal squamous cell carcinoma (ESCC) have a poor prognosis. However, the related mechanisms are unclear, thus we investigated the expression of HO-1 in ESCC tissue and explored possible mechanisms of tumor progression. Expression of HO-1 was examined by immunohistochemistry in 143 ESCC tumors. The correlation of HO-1 with clinicopathological characteristics was also examined. Two human ESCC cell lines, TE-13 and Eca109 were studied. Silencing of cell line HO-1 by specific small interfering RNA (siRNA) was evaluated using real-time quantitative PCR. Cell line viability, apoptosis and intracellular levels of reactive oxygen species (ROS) after transfection were determined using MTT and flow cytometry, respectively. HO-1, Bax, Bcl-2 and A-caspase-3/-9 expression was evaluated using western blot analyses. We found that HO-1 was expressed in 58 of 143 ESCC tumors, mainly in the cytoplasm. There was a significant association between HO-1 expression and tumor grade (P<0.001). Knockdown of HO-1 expression in cell lines was associated with significantly decreased cellular proliferation (P<0.05) and a higher rate of apoptosis (P<0.001) 48 h after treatment. Treatment of the cell lines with the ROS inhibitor N-acetylcysteine abrogated this effect. Knockdown of HO-1 was associated with increased A-caspase-3 and -9 expression, but no change in Bax or Bcl-2 expression or Bax/Bcl-2 ratio was observed. Thus, the present study identified that ESCC tumors frequently expressed HO-1. Knockdown of HO-1 promoted apoptosis through activation of a ROS-mediated caspase apoptosis pathway.

The novel COVID-19 outbreak has affected more than 200 countries and territories as of March 2020. Given that patients with cancer are generally more vulnerable to infections, systematic analysis of diverse cohorts of patients with cancer affected by COVID-19 are needed. We performed a multi-center study including 105 cancer patients and 536 age-matched non-cancer patients confirmed with COVID-19. Our results showed COVID-19 patients with cancer had higher risks in all severe outcomes. Patients with hematological cancer, lung cancer, or with metastatic cancer (stage IV) had the highest frequency of severe events. Non-metastatic cancer patients experienced similar frequencies of severe conditions to those observed in patients without cancer. Patients who received surgery had higher risks of having severe events, while patients with only radiotherapy did not demonstrate significant differences in severe events when compared to patients without cancer. These findings indicate that cancer patients appear more vulnerable to SARS-COV-2 outbreak. Since this is the first large cohort study on this topic, our report will provide the much-needed information that will benefit global cancer patients. As such, we believe it is extremely important that our study be disseminated widely to alert clinicians and patients. Citation Format: Meng-Yuan Dai, Dian-bo Liu, Miao Liu, Fu-Xiang Zhou, Gui-Ling Li, Zhen Chen, Zhi-An Zhang, Hua-You Md, Meng Wu, Qi-Chao Zheng, Yong Xiong, Hui-Hua Xiong, Chun Wang, Chang-Chun Chen, Fei Xiong, Yan Zhang, Ya-Qin Peng, Si-Ping Ge, Bo Zhen, Ting-Ting Yu, Ling Wang, Hua Wang, Yu Liu, Ye-Shan Chen, Jun-Hua Mei, Xiao-Jia Gao, Zhu-Yan Li, Li-Juan Gan, Can He, Zhen Li, Yu-Ying Shi, Yu-Wen Qi, Jing Yang, Daniel G. Tenen, Li Chai, Lorelei Ann Mucci, Mauricio Santillana, Hongbing Cai. Patients with cancer appear more vulnerable to SARS-COV-2: A multi-center study during the COVID-19 outbreak [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 CT406.