RESUMO
BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) is the common cancer with poor prognosis. Long non-coding RNA (lncRNA) ANRIL has been proven to play an important role in many cancers. However up to now, the role of ANRIL in LSCC is still poorly understood. The present study aimed to investigate the role and underlying mechanisms of ANRIL and miR-181a in LSCC. METHODS: Expression of ANRIL, miR-181a and Snai2 in both LSCC tissues and cells was determined by qRT-PCR. CCK-8 assay, colony formation assay, flow cytometry analysis and transwell assay were conducted to detect cell proliferation, clonogenicity, apoptosis, invasion and migration, respectively. The binding between ANRIL and miR-181a, as well miR-181a and Snai2 was confirmed by dual luciferase reporter assay. Western blotting was used to determine the protein levels of Snail, Slug, E-cadherin, N-cadherin and Vimentin. RESULTS: ANRIL was up-regulated while miR-181a was down-regulated in LSCC tissues. ANRIL was negatively correlated with miR-181a and was positively correlated with Snai1 and Snai2. Dual luciferase reporter assay showed ANRIL could directly sponge miR-181a to counteract its suppression on Snai2, serving as a positive regulator of Snai2. Either knockdown of ANRIL or overexpression of miR-181a significantly inhibited the proliferation, clonogenicity, invasion, migration and epithelial mesenchymal transformation (EMT), as well as promoted the apoptosis of LSCC cells, and knockdown of miR-181a reversed the effects. CONCLUSION: Inhibition of ANRIL could suppress cell proliferation, clonogenicity, invasion and migration, as well as enhance cell apoptosis of LSCC cells through regulation of miR-181a/Snai2 axis, indicating that ANRIL might be a promising therapeutic target during the treatment of LSCC.
RESUMO
Representative pioneer tree root systems in the subtropical area of South China were examined with regard to their structure, underground stratification and biomass distribution. Excavation of skeleton roots and observation of fine roots of seven species including the Euphorbiaceae, Theaceae, Melastomataceae, Lauraceae and Fagaceae families was carried out. The results showed that: (1) Pioneer tree roots in the first stage of natural succession were of two types, one characterized by taproot system with bulky plagiotropic branches; the other characterized by flat root system with several tabular roots. The late mesophilous tree roots were characterized by one obvious taproot and tactic braches roots up and down. Shrub species roots were characterized by heart fibrous root type featured both by horizontally and transversally growing branches. Root shapes varied in different dominant species at different stages of succession. (2) Roots of the different species varied in the external features-color, periderm and structure of freshly cut slash. (3) In a set of successional stages the biomass of tree roots increased linearly with the age of growth. During monsoon, the total root biomass amounted to 115.70 t/ha in the evergreen broad-leaved forest; 50.61 t/ha in needle and broad-leaved mixed forest dominated by coniferous forest; and 64.20 t/ha in broad-and needle-leaved mixed forest dominated by broad-leaved heliophytes, and are comparable to the underground biomass observed in similar tropical forests. This is the first report about roots characteristics of forest in the lower sub-tropical area of Dinghushan, Guangdong, China.
