RESUMO
BACKGROUND: Doublecortin-like kinase 2 (DCLK2) is a microtubule-associated protein kinase that participates in neural development and maturation; however, whether it is involved in tumour progression remains unclear. METHODS: DCLK2 overexpression and knockdown clones were established by lentivirus transfection. Western blot, PCR assays and bioinformatics analyses were conducted to observe the expression of DCLK2. CCK8, colony formation, scratch migration and Transwell assays were used to detect cell proliferation, migration and invasion, respectively. Tumour metastasis was evaluated in vivo using a tail vein metastasis model. Bioinformatics analyses were performed to analyse the expression correlation between DCLK2 and TCF4, or EMT markers in breast cancer. RESULTS: Our data indicate that DCLK2 is highly expressed in breast cancer cells and is associated with poor prognosis. Silencing DCLK2 does not affect the proliferation rate of tumour cells, but significantly suppresses migration and invasion as well as lung metastasis processes. Overexpression of DCLK2 can enhance the migratory and invasive abilities of normal breast epithelial cells. Moreover, TCF4/ß-catenin inhibitor LF3 downregulates the expression of DCLK2 and inhibits the migration and invasion of breast cancer cells. Furthermore, we found that the downregulation of DCLK2 blocks the epithelial-mesenchymal transition (EMT) process. CONCLUSION: Our study indicates that DCLK2 plays an important role in EMT, cell invasion and metastasis, suggesting that DCLK2 is a potential target for the treatment of metastatic breast cancer.
Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Humanos , Feminino , Quinases Semelhantes a Duplacortina , Linhagem Celular Tumoral , Neoplasias da Mama/patologia , Neoplasias Pulmonares/genética , Invasividade Neoplásica/genética , Transição Epitelial-Mesenquimal , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Metástase NeoplásicaRESUMO
The distribution of plant species along environmental gradients is expected to be predictable based on organismal function. Plant functional trait research has shown that trait values generally vary predictably along broad-scale climatic and soil gradients. This work has also demonstrated that at any one point along these gradients there is a large amount of interspecific trait variation. The present research proposes that this variation may be explained by the local-scale sorting of traits along soil fertility and acidity axes. Specifically, we predicted that trait values associated with high resource acquisition and growth rates would be found on soils that are more fertile and less acidic. We tested the expected relationships at the species-level and quadrat-level (20 × 20 m) using two large forest plots in Panama and China that contain over 450 species combined. Predicted relationships between leaf area and wood density and soil fertility were supported in some instances, but the majority of the predicted relationships were rejected. Alternative resource axes, such as light gradients, therefore likely play a larger role in determining the interspecific variability in plant functional traits in the two forests studied.