Alternative protein-coding transcripts of the RASSF1 gene have been associated with dual functions in human cancer: while RASSF1C isoform has oncogenic properties, RASSF1A is a tumour suppressor frequently silenced by hypermethylation. Recently, the antisense long non-coding RNA RASSF1 (ANRASSF1) was implicated in a locus-specific mechanism for the RASSF1A epigenetic repression mediated by PRC2 (Polycomb Repressive Complex 2). Here, we evaluated the methylation patterns of the promoter regions of RASSF1A and RASSF1C and the expression levels of these RASSF1 transcripts in breast cancer and breast cancer cell lines. As expected, RASSF1C remained unmethylated and RASSF1A was hypermethylated at high frequencies in 75 primary breast cancers, and also in a panel of three mammary epithelial cells (MEC) and 10 breast cancer cell lines (BCC). Although RASSF1C was expressed in all cell lines, only two of them expressed the transcript RASSF1A. ANRASSF1 expression levels were increased in six BCCs. In vitro induced demethylation with 5-Aza-2ʹ-deoxicytydine (5-Aza-dC) resulted in up-regulation of RASSF1A and an inverse correlation with ANRASSF1 relative abundance in BCCs. However, increased levels of both transcripts were observed in two MECs (184A1 and MCF10A) after treatment with 5-Aza-dC. Overall, these findings indicate that ANRASSF1 is differentially expressed in MECs and BCCs. The lncRNA ANRASSF1 provides new perspectives as a therapeutic target for locus-specific regulation of RASSF1A.

Background: Suggested mechanisms for SARS-CoV-2 direct liver infection have been proposed by others to involve both cholangiocytes and hepatocytes. Early clinical studies have highlighted abnormal liver biochemistry with COVID-19 infection as often not being severe, with elevated liver enzymes <5X the upper limit of normal. Methods: Liver enzymes were evaluated and compared in patients admitted with a diagnosis of COVID-19 in a deidentified Internal Medicine-Medical Teaching Unit/hospitalist admission laboratory database. Comparisons in the incidence of severe liver injury (alanine aminotransferase >10 times upper limit of normal) were made for patients with pre-Omicron SARS-CoV-2 (November 30, 2019, to December 15, 2021) and Omicron SARS-CoV-2 (December 15, 2021, to April 15, 2022). Comprehensive hospital health records were also reviewed for the 2 patient cases discussed. One patient had a liver biopsy that was evaluated with H&E and immunohistochemistry staining using an antibody against COVID-19 spike protein. Results: The evaluation of a deidentified admissions laboratory database found the incidence of severe liver injury was 0.42% with Omicron versus 0.30% with pre-Omicron variants of COVID-19. In both patient cases discussed, abnormal liver biochemistry and a negative comprehensive workup strongly suggest COVID-19 as the cause of severe liver injury. In the one patient with liver biopsy, immunohistochemistry staining suggests SARS-CoV-2 presence in the portal and lobular spaces in association with immune cell infiltration. Conclusions: The Omicron variant of SARS-CoV-2 should be considered in the differential diagnosis of severe acute liver injury. Our observation suggests that this new variant, either through direct liver infection and/or mediating immune dysfunction, can result in severe liver injury.