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The Corona Virus Disease reported in 2019 (COVID-19) poses a significant threat to human and public health. Its early and accurate detection can reduce the spread and recurrence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Real-time reverse transcription fluorescent quantitative polymerase chain reaction (RT-qPCR) is the "gold standard" for detecting the nucleic acid of SARS-CoV-2. This study developed and tested a dual-target (ORF1ab and N gene) one-step nested RT-qPCR (DTO-N-PCR) to detect SARS-CoV-2. Ten-fold serial dilutions of mixed synthetic DNA from SARS-CoV-2 ORF1ab and N gene were used as templates to test the sensitivity of DTO-N-PCR. Its specificity was subsequently tested using throat swab specimens from 10 COVID-19 patients and 35 healthy participants. DTO-N-PCR was more sensitive and specific than conventional RT-qPCR. It has unique features, including a dual-target (ORF1ab and N gene), rapid one-step operation of reverse transcription and PCR, four pairs of inner and outer primers, and specific probes. These features aid in its rapid, accurate, and efficient detection of SARS-CoV-2 RNA. [ABSTRACT FROM AUTHOR]

Abstract Background The purpose of this study was to assess the expression levels for TβRI, TβRII, and TβRIII in epithelial layers of oral premalignant lesions (oral leukoplakia, OLK) and oral squamous cell carcinoma (OSCC), as well as in oral carcinoma-associated fibroblasts (CAFs), with the final goal of exploring the roles of various types of TβRs in carcinogenesis of oral mucosa. Methods Normal oral tissues, OLK, and OSCC were obtained from 138 previously untreated patients. Seven primary human oral CAF lines and six primary normal fibroblast (NF) lines were established successfully via cell culture. The three receptors were detected using immunohistochemical (IHC), quantitative RT-PCR, and Western blot approaches. Results IHC signals for TβRII and TβRIII in the epithelial layer decreased in tissue samples with increasing disease aggressiveness (P < 0.05); no expression differences were observed for TβRI, in OLK and OSCC (P > 0.05); and TβRII and TβRIII were significantly downregulated in CAFs compared with NFs, at the mRNA and protein levels (P < 0.05). Exogenous expression of TGF-β1 led to a remarkable decrease in the expression of TβRII and TβRIII in CAFs (P < 0.05). Conclusion This study provides the first evidence that the loss of TβRII and TβRIII expression in oral epithelium and stroma is a common event in OSCC. The restoration of the expression of TβRII and TβRIII in oral cancerous tissues may represent a novel strategy for the treatment of oral carcinoma.

Abstract Background Hypoxia-inducible transcription factor-1α (HIF-1α), which plays an important role in controlling the hypoxia-induced glycolysis pathway, is a "master" gene in the tissue hypoxia response during tumor development. However, its role in the apoptosis of non-small cell lung cancer remains unknown. Here, we have studied the effects of HIF-1α on apoptosis by modulating HIF-1α gene expression in A549 cells through both siRNA knock-down and over-expression. Methods A549 cells were transfected with a HIF-1α siRNA plasmid or a HIF-1α expression vector. Transfected cells were exposed to a normoxic or hypoxic environment in the presence or absence of 25 mM HEPES and 2-deoxyglucose (2-DG) (5 mM). The expression of three key genes of the glycolysis pathway, glucose transporter type 1(GLUT1), phosphoglycerate kinase 1(PGK1), and hexokinase 1(HK1), were measured using real-time RT-PCR. Glycolysis was monitored by measuring changes of pH and lactate concentration in the culture medium. Apoptosis was detected by TUNEL assay and flow cytometry. Results Knocking down expression of HIF-1α inhibited the glycolysis pathway, increased the pH of the culture medium, and protected the cells from hypoxia-induced apoptosis. In contrast, over-expression of HIF-1α accelerated glycolysis in A549 cells, decreased the pH of the culture medium, and enhanced hypoxia-induced apoptosis. These effects of HIF-1α on glycolysis, pH of the medium, and apoptosis were reversed by treatment with the glycolytic inhibitor, 2-DG. Apoptosis induced by HIF-1α over-expression was partially inhibited by increasing the buffering capacity of the culture medium by adding HEPES. Conclusion During hypoxia in A549 cells, HIF-1α promotes activity of the glycolysis pathway and decreases the pH of the culture medium, resulting in increased cellular apoptosis.

Introduction: Dihydroartemisinin (DHA) is a first-line antimalarial drug with relatively low toxicity. DHA has been speculated to possess a broad-spectrum antitumour effect. However, the potential value of DHA for the treatment of endometrial carcinoma or cervical cancer is unclear.Methods: We used human endometrial cancer cells and cervical cancer cells to assess whether DHA alone or when combined with cisplatin would induce cell death. We aimed to elucidate the role of autophagy in DHA-induced cytotoxicity in both endometrial and cervical cancer cells, and explore the impact of DHA treatment on cell proliferation, apoptosis and autophagy.Results: DHA alone or in combination with cisplatin induced cell death in a dose- and time-dependent manner. Caspase-3 mRNA and cleaved caspase-3 protein levels were markedly elevated following DHA treatment either in the presence or absence of cisplatin, suggesting a role of apoptosis in DHA-induced cell death. DHA treatment activated the autophagic pathway, as evidenced by increased monodansylcadaverine-positive staining, elevated microtubule-associated protein 1 light chain 3 (LC3)-II/LC3-I ratio, and enhanced p62/sequestosome 1 degradation. Inhibition of autophagy by 3-methyladenine further enhanced the cytotoxicity of DHA towards tumour cells. mRNA levels of transferrin receptor (TfR) were suppressed upon DHA treatment and knockdown of TfR by RNA interference caused further DHA induction of cancer cell death.Conclusion: Our results suggest a clinical value for DHA in the treatment of endometrial carcinoma and cervical cancer. Our data revealed possible anticancer mechanisms of DHA that involve regulating apoptosis, autophagy pathway and levels of TfR. [ABSTRACT FROM AUTHOR]