Comparative Analysis of Epigenetic and Gene Expression Endpoints Between Tumorous and Non-tumorous Tissues from HCV-positive Patients with Hepatocellular Carcinoma

Transcriptional silencing induced by promoter CpG island hypermethylation is an important epigenetic mechanism of hepatocarcinogenesis. The goals of our study were to examine promoter methylation and mRNA levels of candidate genes, as well as global changes in DNA methylation, in a cohort of HCV-positive HCC patients from Japan. Methylation-specific PCR was used to assess the methylation status of seven cancer-related genes, while the methylation status of long interspersed nuclear elements was used as marker of global genomic methylation, in tissues obtained from patients who underwent tumor resection surgery. Methylation frequencies for most of the genes were significantly higher in tumorous versus non-tumorous tissues. The methylation status of only three genes correlated with reduced mRNA levels. Genomic DNA was significantly more hypomethylated in tumorous tissues, and was associated with shorter recurrence but not with clinicopathological variables. In summary, this study establishes an aberrant gene-specific and global methylation profile in HCV-associated HCCs

Comparative analysis of promoter methylation and gene expression endpoints between tumorous and non-tumorous tissues from HCV-positive patients with hepatocellular carcinoma

Transcriptional silencing of tumor suppressor genes and other cancer-related genes induced by promoter CpG island hypermethylation is an important epigenetic mechanism of hepatocarcinogenesis. Previous studies have established methylation profiles of hepatocellular carcinomas (HCCs) and demonstrated that methylation of several candidate genes in resected tissues may be associated with time to recurrence. The goals of our study were to test whether specific promoter methylation and mRNA levels of candidate genes, as well as global changes in DNA methylation, can be linked with time to recurrence and clinicopathological variables in a homogenous study group of HCC patients. Forty-three tumorous and 45 non-tumorous liver tissue samples from the surgical margin were obtained from HCV-positive, HBV-negative HCC patients who underwent tumor resection surgery and who were monitored for tumor recurrence thereafter (median follow-up time: 16 months (range, 0 – 79 months)). Methylation-specific PCR was used to assess the promoter methylation status of P16(INK4a), SOCS-1, RASSF1A, APC, GSTP1, RIZ1, and MGMT genes, while the level of LINE-1 methylation was used as marker of global DNA methylation levels. Methylation frequencies in P16(INK4a), RASSF1A, APC, GSTP1, and RIZ1 genes were significantly greater in tumorous versus non-tumorous tissues. Methylation of RIZ1 in non-tumorous tissues was significantly associated with time to recurrence. Additionally, genomic DNA was significantly more hypomethylated in tumorous tissues, and this change was associated with shorter recurrence, but not with clinicopathological features. In conclusion, this study supports the role of aberrant methylation in the pathobiology of HCV-positive HCCs. The finding that RIZ1 methylation and increased levels of LINE-1 hypomethylation in non-tumorous tissues are associated with time to recurrence underscores the importance of assessing the epigenetic state of the liver remnant

Distinct SOX9 levels differentially mark stem/progenitor populations and enteroendocrine cells of the small intestine epithelium

SOX transcription factors have the capacity to modulate stem/progenitor cell proliferation and differentiation in a dose-dependent manner. SOX9 is expressed in the small intestine epithelial stem cell zone. Therefore, we hypothesized that differential levels of SOX9 may exist, influencing proliferation and/or differentiation of the small intestine epithelium. Sox9 expression levels in the small intestine were investigated using a Sox9 enhanced green fluorescent protein (Sox9EGFP) transgenic mouse. Sox9EGFP levels correlate with endogenous SOX9 levels, which are expressed at two steady-state levels, termed Sox9EGFPLO and Sox9EGFPHI. Crypt-based columnar cells are Sox9EGFPLO and demonstrate enriched expression of the stem cell marker, Lgr5. Sox9EGFPHI cells express chromogranin A and substance P but do not express Ki67 and neurogenin3, indicating that Sox9EGFPHI cells are postmitotic enteroendocrine cells. Overexpression of SOX9 in a crypt cell line stopped proliferation and induced morphological changes. These data support a bimodal role for SOX9 in the intestinal epithelium, where low SOX9 expression supports proliferative capacity, and high SOX9 expression suppresses proliferation

Assessment of Sudden Sensorineural Hearing Loss After COVID-19 Vaccination

Importance: Emerging reports of sudden sensorineural hearing loss (SSNHL) after COVID-19 vaccination within the otolaryngological community and the public have raised concern about a possible association between COVID-19 vaccination and the development of SSNHL. Objective: To examine the potential association between COVID-19 vaccination and SSNHL. Design, Setting, and Participants: This cross-sectional study and case series involved an up-to-date population-based analysis of 555 incident reports of probable SSNHL in the Centers for Disease Control and Prevention Vaccine Adverse Events Reporting System (VAERS) over the first 7 months of the US vaccination campaign (December 14, 2020, through July 16, 2021). In addition, data from a multi-institutional retrospective case series of 21 patients who developed SSNHL after COVID-19 vaccination were analyzed. The study included all adults experiencing SSNHL within 3 weeks of COVID-19 vaccination who submitted reports to VAERS and consecutive adult patients presenting to 2 tertiary care centers and 1 community practice in the US who were diagnosed with SSNHL within 3 weeks of COVID-19 vaccination. Exposures: Receipt of a COVID-19 vaccine produced by any of the 3 vaccine manufacturers (Pfizer-BioNTech, Moderna, or Janssen/Johnson and Johnson) used in the US. Main Outcomes and Measures: Incidence of reports of SSNHL after COVID-19 vaccination recorded in VAERS and clinical characteristics of adult patients presenting with SSNHL after COVID-19 vaccination. Results: A total of 555 incident reports in VAERS (mean patient age, 54 years [range, 15-93 years]; 305 women [55.0%]; data on race and ethnicity not available in VAERS) met the definition of probable SSNHL (mean time to onset, 6 days [range, 0-21 days]) over the period investigated, representing an annualized incidence estimate of 0.6 to 28.0 cases of SSNHL per 100000 people per year. The rate of incident reports of SSNHL was similar across all 3 vaccine manufacturers (0.16 cases per 100000 doses for both Pfizer-BioNTech and Moderna vaccines, and 0.22 cases per 100 000 doses for Janssen/Johnson and Johnson vaccine). The case series included 21 patients (mean age, 61 years [range, 23-92 years]; 13 women [61.9%]) with SSNHL, with a mean time to onset of 6 days (range, 0-15 days). Patients were heterogeneous with respect to clinical and demographic characteristics. Preexisting autoimmune disease was present in 6 patients (28.6%). Of the 14 patients with posttreatment audiometric data, 8 (57.1%) experienced improvement after receiving treatment. One patient experienced SSNHL 14 days after receiving each dose of the Pfizer-BioNTech vaccine. Conclusions and Relevance: In this cross-sectional study, findings from an updated analysis of VAERS data and a case series of patients who experienced SSNHL after COVID-19 vaccination did not suggest an association between COVID-19 vaccination and an increased incidence of hearing loss compared with the expected incidence in the general population