Lei Zhang

BACKGROUND: Long non-coding RNAs (lncRNAs) have been identified as critical regulators in the development of atherosclerosis (AS). Here, we focused on discussing roles and molecular mechanisms of lncRNA H19 in vascular smooth muscle cells (VSMCs) progression. METHODS: RT-qPCR assay was used to detect the expression patterns of H19 and miR-148b in clinical samples and cells. Cell proliferative ability was evaluated by CCK-8 and colony formation assays. Cell apoptotic capacity was assessed by apoptotic cell percentage and the caspase-3 activity. Bioinformatics analysis, luciferase and RNA immunoprecipitation (RIP) assays were employed to demonstrate cell percentage and the relationship among H19, miR-148b and wnt family member 1 (WNT1). Western blot assay was performed to determine expressions of proliferating cell nuclear antigen (PCNA), ki-67, Bax, Bcl-2, WNT1, β-catenin, C-myc and E-cadherin. RESULTS: The level of H19 was increased and miR-148b expression was decreased in human AS patient serums and oxidized low-density lipoprotein (ox-LDL)-stimulated human aorta vascular smooth muscle cells (HA-VSMCs). H19 knockdown suppressed proliferation and promoted apoptosis in HA-VSMCs following the treatment of ox-LDL. H19 inhibited miR-148b expression by direct interaction. Moreover, miR-148b inhibitor could reverse the effects of H19 depletion on proliferation and apoptosis in ox-LDL-stimulated HA-VSMCs. Further mechanical explorations showed that WNT1 was a target of miR-148b and H19 acted as a competing endogenous RNA (ceRNA) of miR-148b to enhance WNT1 expression. Furthermore, miR-148 inhibitor exerted its pro-proliferation and anti-apoptosis effects through activating WNT/β-catenin signaling in ox-LDL-stimulated HA-VSMCs. CONCLUSION: H19 facilitated proliferation and inhibited apoptosis through modulating WNT/β-catenin signaling pathway via miR-148b in ox-LDL-stimulated HA-VSMCs, implicating the potential values of H19 in AS therapy.

Abstract Hepatic stellate cells (HSCs) have immunosuppressive capabilities and contribute to the occurrence and development of hepatocellular carcinoma (HCC). Thus, activated HSCs may be a suitable target for HCC therapy. Our study used mixed leukocyte reactions (MLR) in vitro to demonstrate that 18β‐glycyrrhetinic acid (GA) could reverse HSC‐mediated immunosuppression by reducing T‐cell apoptosis and regulatory T (Treg) cells expression, thereby enhancing the ability of T cells to attack tumor cells and attenuating HCC cell invasiveness. Moreover, we established a HCC orthotopic implantation model in immunocompetent C57BL/6 mice, which suggested that GA played a protective role in HCC development by reducing immunosuppression mediated by HSCs in the tumor microenvironment.

OBJECTIVES: Breast cancer is the most common malignant tumor among females, and miRNAs have been reported to play an important regulatory role in breast cancer progression. This study aimed to explore the function and underlying molecular mechanism of miR-301b-3p in breast cancer. METHODS: Differential analysis and survival analysis were performed based on the data accessed from the TCGA-BRCA dataset for identification of the target miRNA. Bioinformatics analysis was conducted to predict the downstream target gene of the miRNA. Real-time quantitative PCR was carried out to detect the expression of miR-301b-3p and nuclear receptor subfamily 3 group C member 2 (NR3C2). Western blot was used to assess the protein expression of NR3C2. Cell counting kit-8 assay was performed to evaluate the proliferation of breast cancer cells. Transwell assay was conducted to determine the migratory and invasive abilities of breast cancer cells. Dual-luciferase reporter assay was employed to verify the targeting relationship between miR-301b-3p and NR3C2. RESULTS: miR-301b-3p was elevated in breast cancer cell lines and promoted cell proliferation, migration, and invasion in terms of its biological function in breast cancer. NR3C2 was validated as a direct target of miR-301b-3p via bioinformatics analysis and dual-luciferase reporter assay, and NR3C2 was downregulated in breast cancer cell lines. The rescue experiment indicated that NR3C2 was involved in the mechanism by which miR-301b-3p regulated the malignant phenotype of breast cancer cells. CONCLUSION: The present study revealed for the first time that miR-301b-3p could foster breast cancer cell proliferation, migration, and invasion by targeting NR3C2, unveiling that miR-301b-3p is a novel carcinogen in breast cancer.

Xanthatin, a natural bioactive compound of sesquiterpene lactones, was isolated and purified from air-dried aerial part of Xanthium sibiricum Patrin ex Widder. In the present study, we demonstrated the significant antiproliferative and proapoptotic effects of xanthatin on human gastric carcinoma MKN-45 cells. MTS assay showed that xanthatin produced obvious cytotoxicity in MKN-45 cells with IC50 values of 18.6, 9.3, and 3.9 µM for 12, 24, and 48 h, respectively. Results of flow cytometry analysis indicated that the antiproliferative activity induced by xanthatin might be executed via G2/M cell cycle arrest and proapoptosis in MKN-45 cells. Western blot analysis elucidated that: a) xanthatin downregulated expression of Chk1 and Chk2 and phosphorylation of CDC2, which are known as key G2/M transition regulators; b) xanthatin increased p53 activation, decreased the bcl-2/bax ratio and the levels of downstream procaspase-9 and procaspase-3, which are key regulators in the intrinsic apoptosis pathway; c) xanthatin blocked phosphorylation of NF-κB (p65 subunit) and of IκBα, which might contribute to its proapoptotic effects on MKN-45 cells. In conclusion, our results suggest that xanthatin may have therapeutic potential against human gastric carcinoma.