Using differential display PCR, we have identified a gene [NOEY2, ARHI (designation by the Human Gene Nomenclature Committee)] with high homology to ras and rap that is expressed consistently in normal ovarian and breast epithelial cells but not in ovarian and breast cancers. Reexpression of NOEY2 through transfection suppresses clonogenic growth of breast and ovarian cancer cells. Growth suppression was associated with down-regulation of the cyclin D1 promoter activity and induction of p21 WAF1͞CIP1 . In an effort to identify mechanisms leading to NOEY2 silencing in cancer, we found that the gene is expressed monoallelically and is imprinted maternally. Loss of heterozygosity of the gene was detected in 41% of ovarian and breast cancers. In most of cancer samples with loss of heterozygosity, the nonimprinted functional allele was deleted. Thus, NOEY2 appears to be a putative imprinted tumor suppressor gene whose function is abrogated in ovarian and breast cancers.

ARHI is a maternally imprinted tumor suppressor gene whose expression is markedly downregulated in breast cancer. Reactivation of ARHI expression in breast cancer cells is associated with increased histone H3 acetylation and decreased lysine 9 methylation of histone H3. An ARHI promoter segment that spanned bases À420 to þ 58 (designated the P2 region) exhibits significantly higher promoter activity in normal cells than in cancer cells. To better understand the molecular mechanisms contributing to this differential transcriptional activity, we sought to identify transcription factors that bind to the P2 region of the ARHI promoter and regulate its activity. Sequence analysis and oligonucleotide competition in electrophoretic mobility shift assays identified an A2 fragment containing an E2F-binding site. Using specific antibodies in supershift assays, we have shown that anti-E2F1 and 4 antibodies can supershift the A2-protein complexes, whereas anti-E2F2 and 6 antibodies cannot, demonstrating that the A2 fragment interacts with specific members of the E2F family proteins. When compared with normal breast epithelial cells, breast cancer cells have significantly elevated expression of E2F1, 4 and increased E2F DNA-binding activity. Moreover, chromatin immunoprecipitation experiments revealed that both E2F1 and 4 bind to the ARHI promoter in breast cancer cells in vivo. This binding was reduced when the cells were treated with the histone deacetylase (HDAC) inhibitor -trichostatin A (TSA). When SKBr3 cells were cotransfected with an ARHI/ luciferase reporter and E2F-expression vectors, E2F1 and 4 reduced ARHI promoter activity 2-3-fold, and this reduction could be reversed by TSA treatment. The negative regulation by E2F-HDAC complexes could also be reduced by small interfering RNA of E2F1 and 4. While the retinoblastoma protein, pRB, alone had no effect on ARHI promoter activity, repression by E2F1, but not E2F4, was enhanced by the coexpression of pRB. Taken together, our results suggest that E2F1, 4 and their complexes with HDAC play an important role in downregulating the expression of the tumor suppressor gene ARHI in breast cancer cells.

Acute respiratory distress syndrome virus-2 (SARS-CoV-2) responsible for coronavirus disease 2019 (COVID-19) infection, which causes global public health emergencies, has sped widely for more than 5 months and has the risk of long-term transmission. No effective treatment has been discovered to date. In the cases we report, the patient continued to deteriorate even after administration of antiviral drugs such as lopinavir/ritonavir, interferon-α, and ribavirin, as well as intravenous injection of meropenem, methylprednisolone, and immunoglobulin. So, we infused the patient with convalescent plasma (CP), and the absolute lymphocyte count increased the next day and returned to normal on the fourth day. Followed by intravenous infusion of mesenchymal stem cells (MSCs), bilateral infiltrates were absorbed and the pulmonary function was significantly improved. We note that the intravenous infusion of CP and MSCs for the treatment of severe COVID-19 patients may have synergistic characteristics in inhibiting cytokine storm, promoting the repair of lung injury, and recovering pulmonary function. We hope to provide a reference for the research direction of COVID-19 clinical strategies.

In our previous work, we had characterized ARHI as an imprinted putative tumor‐suppressor gene in ovarian and breast cancers. ARHI is expressed in primary breast and ovarian cell lines but largely absent from the corresponding malignant tumors. Moreover, the non‐imprinted functional allele is typically deleted in malignant cells. Since ARHI had been mapped to 1p31, a common deletion site in breast and ovarian cancer and male germ‐cell tumors, in this study, we set out to define precisely the physical location of ARHI at 1p31 and to determine if this location lies within the smallest common region of deletion in breast and ovarian cancers. To this end, we first carried out radiation hybrid mapping of ARHI and surrounding markers, followed by a high‐resolution study of loss of heterozygosity at 1p31 in 49 ovarian and breast cancers. Combining a radiation hybrid map and a physical map of the region encompassing ARHI, 3 discrete regions of minimal deletion were found at 1p31 in breast and ovarian cancers. ARHI is the most common deletion region at 1p31. Two other less common regions of deletion were found centromeric to this gene. One of them centered on D1S207 and the other one included and was proximal to D1S488. We also confirmed the preferential loss of non‐imprinted functional allele in 7 of 9 tumor specimens. These data support the possibility that ARHI is a tumor‐suppressor gene and suggest that additional tumor‐suppressor genes may lie proximal to ARHI at 1p31. The data obtained from our study should aid in the identification and characterization of genes in this novel imprinted region. Int. J. Cancer 86:690–694, 2000. © 2000 Wiley‐Liss, Inc.

Purpose: ARHI expression is lost or markedly down-regulated in the majority of ovarian cancers.The mechanism by which ARHI is down-regulated in ovarian cancers is still not clear. Our previous reports indicated that ARHI promoter activity was reduced in ovarian cancer cells, due in part to the effects of negative regulatory transcription factor(s). Experimental Design and Results: We now show that E2F1and E2F4, but not E2F2, E2F3, or E2F5, bind to the ARHI promoter and repress its activity in ovarian cancer cells. Consistent with this observation, immunochemical staining of cell lines and of 364 samples of ovarian cancer tissue show that the expression of E2F1and E2F4 proteins is much higher in ovarian cancer cells than in normal ovarian epithelial cells, and that increased expression of E2Fs was negatively correlated with ARHI expression (P < 0.05). Mutation of the putative E2F binding site in the ARHI promoter reversed this inhibitory effect and significantly increased ARHI promoter activity. In addition to the effects of transcriptional regulation, ARHI mRNA also exhibited a significantly reduced half-life in ovarian cancer cells when compared with that in normal ovarian epithelial cells (P < 0.01), suggesting posttranscriptional regulation of ARHI expression. ARHI mRNA contains AU-rich elements (ARE) in the 3V -untranslated region. We have found that these AREs interact with HuR, an AREbinding protein that stabilizes bound mRNAs, possibly contributing to the rapid turnover of ARHI mRNA. Finally, reduced HuR ARE binding activity was observed in ovarian cancer cells when compared with normal ovarian surface epithelium. Conclusions: Taken together, our data suggest that ARHI expression is regulated at both the transcriptional and the posttranscriptional levels, contributing to the dramatic decrease in ARHI expression in ovarian cancers.

No abstract

Background: Weight loss by lifestyle modification is the cornerstone therapy of non-alcoholic fatty liver disease (NAFLD). Intermittent fasting has shown favorable effects on body weight (BW) and relevant indicators of NAFLD in several reports.Objective: To estimate the effects of intermittent fasting on adults with NAFLD.Materials and methods: Literature searches were conducted on PubMed, EMBASE, Web of Science, Cochrane Library, and ClinicalTrials.gov from inception to May 10, 2021.Results: A total of six studies involving 417 patients with NAFLD were included. In the meta-analysis, there were significant differences in BW, body mass index (BMI), alanine aminotransferase (ALT), and aspartate transaminase (AST) between the control and fasting group. Up to now, there is no significant difference in triglycerides (TG), total cholesterol (TC), and other metabolic parameters between the two groups.Conclusions: Intermittent fasting is beneficial for weight management and liver enzyme improvement, but long-term feasibility and safety of intermittent fasting should be conducted in further studies.

Age, hypercholesterolemia, and vitamin D deficiency are risk factors that increase the brain accumulation of pathogenic β‐amyloid peptides (40 and 42), precursors leading to Alzheimer's disease (AD) in humans. The relative changes accompanying aging, high cholesterol, and/or treatment of calcitriol, active vitamin D receptor (VDR) ligand, under normal physiology are unknown. We examined these relative changes in C57BL/6 mice of ages 2, 4–8, and more than 10 months old, which were fed a normal or high fat / high cholesterol diet and treated with calcitriol, active ligand of the vitamin D receptor (0 or 2.5 μg/kg ×4, intraperitoneally, every other day to elicit cholesterol lowering in liver). Aβ40 but not Aβ42 accumulation in brain and lower P‐glycoprotein (P‐gp) and neprilysin protein expressions for Aβ efflux and degradation, respectively, were found to be associated with aging. But there was no trend for BACE1 (β‐secretase 1, a cholesterol‐sensitive enzyme) toward Aβ synthesis with age. In response to calcitriol treatment, P‐gp was elevated, mitigating partially the age‐related changes. Although age‐dependent decreasing trends in mRNA expression levels existed for Cyp46a1, the brain cholesterol processing enzyme, whose inhibition increases BACE1 and ApoE to facilitate microglia Aβ degradation, mRNA changes for other cholesterol transporters: Acat1 and Abca1, and brain cholesterol levels remained unchanged. There was no observable change in the mRNA expression of amyloid precursor protein (APP) and the influx (RAGE) and efflux (LRP1) transporters with respect to age, diet, or calcitriol treatment. Overall, aging poses as a risk factor contributing to Aβ accumulation in brain, and VDR‐mediated P‐gp activation partially alleviates the outcome.