Prolonged fecal shedding of SARS-CoV-2 in a young immunocompetent COVID-19 patient: A case report and literature overview.

Clinicians are facing several challenges in tackling coronavirus disease 2019 (COVID-19); one issue is prolonged detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA. Here, we describe a case of SARS-CoV-2 infection in a young immunocompetent patient with a virological course lasting for 71 days. Following antiviral treatment, but no additional glucocorticoid or interferon therapy, the patient recovered from COVID-19 pneumonia (moderate). Detection of viral RNA via throat swabs showed negative results. However, the viral RNA reappeared and persisted in stool samples for an additional 27 days, while the patient remained asymptomatic and exhibited no abnormal signs. This case indicates that SARS-CoV-2 can result in a prolonged fecal RNA shedding, even in an immunocompetent patient with zero exposure to immunosuppressive therapies.

MicroRNA-301a (miR-301a) is induced in hepatocellular carcinoma (HCC) and down- regulates the expression of interferon regulatory factor-1.

Hepatocellular carcinoma (HCC) tumors evade death in part by downregulating expression of the tumor suppressor gene Interferon regulatory factor-1 (IRF-1). However, the molecular mechanisms accounting for IRF-1 suppression in HCC have not been well described. In this study, we identified a novel microRNA-301a (miR-301a) binding site in the 3'-untranslated region (3'- UTR) of the human IRF-1 gene and hypothesized a functional role for miR-301a in regulating HCC growth. We show that miR-301a is markedly upregulated in primary HCC tumors and HCC cell lines, while IRF-1 is down-regulated in a post-transcriptional manner. MiR-301a regulates basal and inducible IRF-1 expression in HCC cells with an inverse relationship between miR-301a and IRF-1 expression in HCC cells. Chronic hypoxia induces miR-301a in HCC in vitro and decreases IRF-1 expression. Finally, miR-301a inhibition increases apoptosis and decreases HCC cell proliferation. These findings suggest that targeting of IRF-1 by miR-301a contributes to the molecular basis for IRF-1 downregulation in HCC and provides new insight into the regulation of HCC by miRNAs.

miR-383 promotes cholangiocarcinoma cell proliferation, migration, and invasion through targeting IRF1.

Interferon regulatory factor 1 (IRF1) has been found to serve as a tumor suppressor in cholangiocarcinoma, and enabled prediction of clinical progression and prognosis in our previous study. The objective of the current study is to screen and identify valuable microRNAs (miR), which target IRF1 to regulate cholangiocarcinoma cell proliferation, migration, and invasion. High expression of miR-383 was observed in cholangiocarcinoma tissues and cells. Meanwhile, we found the predicted binding site of miR-383 on the IRF1 3'-untranslated region (3'-UTR) according to the miR target database. The miR-383 expression was negatively related to IRF1 messeneger RNA (mRNA) and protein expression in cholangiocarcinoma tissue samples, and miR-383 negatively regulated IRF1 mRNA and protein expression in cholangiocarcinoma cells. Subsequently, we conducted a luciferase reporter assay to prove the predicted binding site miR-383 on IRF1 3'-UTR. Moreover, the results of the rescue study suggested that IRF1 was a functional target of miR-383 involved in regulating cholangiocarcinoma cell proliferation, migration, and invasion. Finally, we evaluated the clinical and prognostic significance of miR-383 in cholangiocarcinoma cases, and found that high expression of miR-383 was correlated with advanced tumor stage, large tumor size, present vascular invasion, and metastasis, and acted as an unfavorable independent prognostic factor. In conclusion, miR-383 serves as a tumor-suppressive miR to regulate cholangiocarcinoma cell proliferation, migration, and invasion via directly targeting IRF1.

Potential protective effect of hesperidin on hypoxia/reoxygenation-induced hepatocyte injury.

Hesperidin (HDN) has been reported to have hydrogen radical- and hydrogen peroxide-removal activities and to serve an antioxidant role in biological systems. However, whether HDN protects hepatocytes (HCs) against hypoxia/reoxygenation (H/R)-induced injury remains unknown. The present study aimed to explore the role of HDN in H/R-induced injury. HCs were isolated and cultured under H/R conditions with or without HDN treatment. HC damage was markedly induced under H/R, as indicated by cell viability, supernatant lactate dehydrogenase levels and alanine aminotransferase levels; however, HDN treatment significantly reversed HC injury. Oxidative stress markers (malondialdehyde, superoxide dismutase, glutathioneand reactive oxygen species) were increased markedly during H/R in HCs; however, this effect was significantly attenuated after exposure to HDN. Compared with those of the control group, the mRNA expression levels of IL-6 and TNF-α in HCs and the concentrations of IL-6 and TNF-α in the supernatants increased significantly following H/R, and HDN significantly ameliorated these effects. Western blotting demonstrated that microtubule-associated protein 1 light chain 3α (MAP1LC3A, also known as LC3) and Beclin-1 protein expression levels increased, while sequestosome 1 levels decreased during H/R following exposure to HDN. The number of GFP-LC3 puncta in HCs following exposure to HDN was increased compared with that observed in HCs without HDN exposure under the H/R conditions after bafilomycin A1 treatment. In summary, the present study demonstrated that HDN attenuated HC oxidative stress and inflammatory responses while enhancing autophagy during H/R. HDN may have a potential protective effect on HCs during H/R-induced injury.

MicroRNA200a enhances antitumor effects in combination with doxorubicin in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is often treated with doxorubicin. MicroRNAs have been shown to have important regulatory roles in cancer and serve as a target in chemoresistance. In this study, we investigated the effects of specific microRNA-200a (miR-200a) on HCC tumor cell growth and effect of doxorubicin-mediated cytotoxicity. Our results show miR-200a is downregulated in human HCC and HCC tumor cell lines. Increasing miR-200a expression inhibited HCC growth and synergized with the antitumor effects of doxorubicin. Inhibiting endogenous miR-200a promoted tumor growth and chemotherapeutic resistance. Increasing miR-200a expression inhibited tumor metabolism (ATP production, mitochondrial respiration, glycolysis), while inhibition of endogenous miR-200a reversed these effects. MiR-200a expression also increased autophagy and synergized with doxorubicin-mediated cytotoxicity. This study identifies a novel role of miR-200a in potentiating doxorubicin-mediated therapeutic effects in HCC.

The clinical significance and biological function of interferon regulatory factor 1 in cholangiocarcinoma.

Interferon regulatory factor 1 (IRF1) has been suggested to act as a tumor suppressor in human cancers. However, the clinical significance and biological function of IRF1 in cholangiocarcinoma is poorly understood. In our results, IRF1 mRNA and protein expressions were decreased in cholangiocarcinoma tissues and cell lines compared with paired normal hepatic tissues and intrahepatic bile duct epithelial cell line. IRF1 protein low-expression was associated with tumor stage, tumor size, vascular invasion and metastasis and served as a poor independent prognostic parameter in cholangiocarcinoma patients. Up-regulation of IRF1 expression suppressed cholangiocarcinoma cells proliferation, migration and invasion, and blocked cell cycle progression, but has no effect on apoptosis. In conclusion, IRF1 is low-expressed in cholangiocarcinoma tissues and cell lines, and correlated with malignant status and prognosis in cholangiocarcinoma patients. IRF1 served as tumor suppressor in the regulation of cholangiocarcinoma cells proliferation, cell cycle, migration and invasion.

Associations between sequence variations in the mitochondrial DNA D-loop region and outcome of hepatocellular carcinoma.

The association between mitochondrial DNA (mtDNA) polymorphisms or mutations and the prognoses of cancer have been investigated previously, but the results have been ambiguous. In the present study, the associations between sequence variations in the mtDNA D-loop region and the outcomes of patients with hepatocellular carcinoma (HCC) were analysed. A total of 140 patients with HCC (123 males and 17 females), who were hospitalised to undergo radical resection, were studied. Polymerase chain reaction and direct sequencing were performed to detect the sequence variations in the mtDNA D-loop region. Multivariate and univariate analyses were conducted to determine important factors in the prognosis of HCC. A total of 150 point sequence variations were observed in the 140 cases (13 point mutations, 8 insertions, 20 deletions and 116 polymorphisms). The variation rate was 13.4% (150/1, 122). mtDNA nucleotide 150 (C/T) was an independent factor in the logistic regression for early/late recurrence of HCC. Patients with 150T appeared to have later recurrences. In a Cox proportional hazards regression model, hepatitis B virus DNA, Child-Pugh class, differentiation degree, tumour-node-metastasis (TNM) stage, nucleotide 16263 (T/C) and nucleotide 315 (N/insertion C) were independent factors for tumour-free survival time. Patients with the 16263T allele had a greater tumour-free survival time than patients with the 16263C allele. Similarly, patients with 315 insertion C had a superior tumour-free survival time when compared with patients with 315 N (normal). In the Cox proportional hazards regression model, recurrence type (early/late), Child-Pugh class, TNM stage and adjuvant treatment after tumour recurrence (none or one/more than one treatment) were independent factors for overall survival. None of the mtDNA variations served as independent factors. Patients with late recurrence, Child-Pugh class A, and low TNM stages and/or those who received more than one adjuvant treatment following tumour recurrence had favourable outcomes. mtDNA D-loop polymorphisms were associated with early recurrence and tumour-free survival time, but not with overall survival. mtDNA D-loop mutations in HCC were infrequent and lacked prognostic utility. The detection of mtDNA D-loop polymorphisms may assist in identifying risk factors for HCC prognosis, particularly for the short-term outcome, thereby aiding the construction of an appropriate therapeutic strategy.