RESUMO
BACKGROUND: Colorectal cancer is a worldwide leading cause of death accounting for high-rate mortality. Mutations in the epidermal growth factor receptor and RAS/MAPK pathways, as well as altered methylation genes profiles, have been described as molecular mechanisms promoting and sustaining tumour development and progression. Aberrant methylation is a well-known epigenetic mechanism involved in gene regulation; particularly several genes were reported as hypermethylated in CRC. Recently, it was shown that epigenetic alterations in genes such as neuropeptide y, proenkephalin and Wnt inhibitory factor 1 can be used as promising disease biomarkers. Almost all methods developed for the DNA methylation analysis combined next generation sequencing, conventional qRT-PCR or ddPCR with the prior DNA modification with sodium bisulfite. METHODS AND RESULTS: We implemented a ddPCR method to assess the methylation status of Wnt inhibitory factor 1 and neuropeptide y using the methylation sensitive restriction enzyme approach that does not impact on DNA quality and guarantees the discrimination of DNA methylation independent of bisulfite conversion. CONCLUSIONS: We showed that this method is robust and sensitive also allowing the monitoring of CRC disease progression when applied to circulating free DNA samples from liquid biopsies, proving to be a fast and easy to implement assay to be used for the monitoring of the methylation pattern of clinically relevant target genes.
RESUMO
INTRODUCTION: We analyzed a cohort of patients with cancer and Sars-Cov-2 infection from the Veneto Oncology Network registry across two pandemic time periods. MATERIALS AND METHODS: 761 patients with cancer and SARS-CoV-2 infection were included. RESULTS: 198 patients were diagnosed during the first pandemic time period (TP1; February 2020 September 2020), 494 during TP2 before the vaccination campaign (TP2/pre-vaccination; September 2020-21 February 2021) and 69 in TP2/post-vaccination (22 February 2021-15 May 2021). TP2 vs TP1 patients were younger (p = 0.004), showed more frequently a good performance status (p < 0.001) and <2 comorbidities (p = 0.002), were more likely to be on active anticancer therapy (p = 0.006). Significantly fewer patients in TP2 (3-4%) vs TP1 (22%) had an in-hospital potential source of infection (p < 0.001). TP2 patients were more frequently asymptomatic (p = 0.003). Significantly fewer patients from TP2 were hospitalized (p < 0.001) or admitted to intensive care unit (p = 0.006). All-cause mortality decreased from 30.3% in TP1, to 8.9% and 8.7% in the two TP2 periods (p < 0.001), reflected by a significant reduction in Sars-Cov-2-related mortality (15.2%, 7.5% and 5.8% in the three consecutive time periods, p = 0.004). CONCLUSIONS: Differences in clinical characteristics and features of Sars-Cov-2 infection between TP1 and TP2 reflect the effects of protective measures and increased testing capacity. The lower mortality in TP2 is in line with a less frail population. However, the vast majority of death events in TP2 were related to COVID-19, reinforcing the priority to protect cancer patients.