No abstract

Abstract. Hepatitis B virus (HBV) X protein (HBx) plays a key role in the initiation and progression of HBV infection-induced hepatocellular carcinoma (HCC). Oncogenic microRNA-21 (miR-21) can be modulated by HBx protein in HCC. However, critical regulator genes in the pathway of HBx-induced miR-21 in HCC remain unclear. This study aimed to investigate the role of HBx-induced miR-21 in the apoptosis of HCC cells. In the study, interleukin-12 (IL-12) was demonstrated as a direct target of miR-21 by dual-luciferase report assay, and miR-21 was highly expressed in HCC cells (HepG2 and HepG2 2.2.15) compared to L02 cells, but IL-12 was weakly expressed as detected by real-time quantitative PCR (RT-qPCR). Furthermore, miR-21 mimics, inhibitor, HBx-targeted siRNA, and the HBx overexpression vector (pHBx) were used to observe the regulatory effects of HBx-induced miR-21 via IL-12, and cell apoptosis was assessed. The results showed that overexpression of HBx resulted in the inhibition of IL-12. A high level of miR-21 resulted in a significant increase in proliferation and a decrease in IL-12 expression. Inhibition of miR-21 resulted in a significant increase in apoptosis and increased IL-12 expression. The results suggest that HCC cell apoptosis was suppressed at least partially through HBx-induced miR-21 by targeting IL-12.

Breast cancer is a malignant tumor that occurs in the glandular epithelial tissues of the breast. It is one of the most common malignant tumors in women. This study was aimed at investigating the role of cell-free DNA (cfDNA) as a potential biomarker for breast cancer diagnosis. Patients with primary breast cancer (n =110) were enrolled in the experimental group, 95 patients with benign breast tumors were in control group 1, while 90 healthy volunteers were in control group 2. Quantitative PCR was used to determine cfDNA concentration and integrity in each group. The cfDNA levels in different groups and their relationship with clinical features of breast cancer patients were analyzed. Receiver operational curves were established to analyze sensitivity and specificity of cfDNA concentration, cfDNA integrity, CEA, CA125 and CA15-3. The cfDNA concentration and cfDNA integrity of the experimental group were significantly higher than those of control groups 1 and 2. The cfDNA concentration and integrity in plasma of experimental group after chemotherapy were significantly lower than those before chemotherapy. While CEA and CA15-3 expressions were significantly correlated with cfDNA concentration, CA125 expression was significantly correlated with cfDNA integrity. Results from ROC curve analysis showed that the sensitivity and specificity of cfDNA concentration and integrity were higher than those of traditional tumor biomarkers. These results indicate that cfDNA concentration and integrity are significantly higher in primary breast cancer patients than in benign breast tumor patients and healthy people. Thus, cfDNA may serve as a potential biomarker of breast cancer.

Objective: Osteosarcoma is one of the most common malignancies in children and adolescents. Studies have shown that miR-34c-5p is involved in the progression of various cancers. To explore the effects of miR-34c-5p on the proliferation, migration and invasion of osteosarcoma cells and its potential mechanism. Methods: qRT-PCR was used to detect the expression levels of miR-34c-5p and FLOT2 mRNA in osteosarcoma tissues and cells. Western Blot was used to detect protein expression. MTT assay used to detect cell viability. Transwell was used to detect cell migration and invasion in each group. Dual luciferase reporter gene assay was used to detect luciferase activity. Results: The expression of miR-34c-5pwas significantly decreased in osteosarcoma tissues and cells and the expression level of FLOT2 mRNA was significantly increased. Overexpression of miR-34c-5p and inhibition of FLOT2 inhibited the proliferation, migration and invasion of osteosarcoma cells and inhibited the expression of Cyclin D1, MMP-2 and MMP-9 proteins and promoted the expression of p21 protein. miR-34c-5p targeted to regulate the expression of FLOT2. Overexpression of FLOT2 reversed the inhibitory effect of miR-34c-5p overexpression on proliferation, migration and invasion of osteosarcoma cell lines. Conclusion: miR-34c-5p can inhibit the proliferation, migration and invasion of osteosarcoma cells. The mechanism may be related to targeting FLOT2, which will provide a new target for the prevention and treatment of osteosarcoma.

No abstract