Background: The aim of this study was to investigate the knowledge, attitudes, and practices of the Greek general population toward coronavirus disease 2019 (COVID-19) during the lockdown period in April 2020, to examine factors associated with misperceptions and to determine behavioral patterns that may require interventions. Methods: A cross-sectional study of the general Greek population (N = 1858) was conducted. A geographically stratified cluster sampling was implemented. A questionnaire was composed consisting of 35 questions. Data collection took place from 15 April to 2 May 2020. A random-digit dialing survey was conducted by 29 interviewers. Results: The majority of respondents (62.7%) answered ≥12/17 questions correctly. Participants aged 18–44 years, male gender, specific occupations (freelancer, unemployed, housewife, retiree) and those who sought information about COVID-19 from less than two sources received lower aggregated scores on knowledge questions. Regarding attitudes toward future vaccination, 18.9% declared that were against it, while 81.1% that they may consider or will be vaccinated. About 40% were not using a face mask and only 42% washed their hands appropriately. Conclusion: Adjusting information campaigns targeting especially people below 45 years of age can help to sensitize them and realise their role to control the spread. Further targeted surveys are needed to adjust/design prevention campaigns.

68 Background: EACs often carry amplifications in MYC (19%) and mutations in the SWI/SNF complex (13%) which act as oncogenic drivers. Targeting of MYC-amplified tumors via BET inhibition, as well as HDAC2 or EZH2 inhibition in SWI/SNF-mutated tumors, show promise in hematological cancers, and solid tumors, respectively. Herein, we investigate the effects of BET, HDAC2, and EZH2 inhibition on EAC cell line proliferation. Methods: MYC-wild type (n = 5), MYC-amplified (n = 2), SWI/SNF-wild type (n = 6) and SWI/SNF-mutant (n = 1) EAC cell lines that have undergone whole genome sequencing (WGS) were plated at 10% confluency and treated with BET (JQ1), pan-HDAC (SAHA), and EZH2 (EPZ-6438) inhibitors at various concentrations. The CellTiter-Glo cell proliferation assay was used to compare the effects of drug treatment on proliferation between different cell lines and drug concentrations before and after treatment. Results: MYC-amplified EAC cell lines were more sensitive to BET inhibition (Table); GI50 concentrations for JQ1 are comparable to those achieved in melanoma and lymphoma cell lines, cancer types in which clinical activity has been demonstrated. ERBB2 amplified or ERBB2 mutant EAC cells were also sensitive to BET inhibition. HDAC2 inhibition reduced proliferation of both SWI/SNF-wild type and mutant cell lines at high concentrations, whilst all cell lines were resistant to EZH2 inhibition, even at the highest concentrations used. Conclusions: MYC amplified EAC tumors appear to be sensitive to BET inhibition; these results warrant further evaluation in pre-clinical models and clinical trials. HDAC2 and EZH2 inhibition were ineffective in both the SWI/SNF-wild type and mutant type EAC cell lines; these therapies are less likely to provide benefit for EAC patients.