Long noncoding RNA KB-1980E6.3 promotes breast cancer progression through the PI3K/AKT signalling pathway.

This research aims to investigate the effect of lncRNA KB-1980E6.3 on the biological behaviour of breast cancer cells under normoxic conditions and the underlying molecular mechanism. The expression of KB-1980E6.3 in breast cancer tissues and cells was detected by RT-qPCR. The proliferation, migration and invasion of cells were evaluated by CCK-8, colony formation, scratch and Transwell assays; KB-1980E6.3-related xenograft models were established for in vivo studies. The protein expression of PI3K, p-PI3K, AKT and p-AKT was validated by western blotting analysis. The levels of KB-1980E6.3 are significantly upregulated in breast cancer tissues and cells and are related to the poor prognosis. Functional research both in vivo and in vitro revealed that the downregulation of KB-1980E6.3 expression significantly decreased cell proliferation, invasion and migration, while ectopic KB-1980E6.3 expression obviously promoted these biological phenotypes. In terms of the mechanism, KB-1980E6.3 is involved in the activation of the PI3K/AKT signalling pathway. Knockdown of KB-1980E6.3 reduced the expression of the p-PI3K and p-AKT proteins, whereas KB-1980E6.3 overexpression showed the opposite result. The agonist 740Y-P and inhibitor LY294002 reversed the effect of KB-1980E6.3 knockdown and overexpression on the PI3K/AKT pathway in BC cells. KB-1980E6.3 promotes the proliferation, invasion and migration of breast cancer cells by activating PI3K/AKT signalling, which can be used as a potential target for breast cancer therapy.

Genetic Bases of the Stomata-Related Traits Revealed by a Genome-Wide Association Analysis in Rice (Oryza sativa L.).

Stomatal density (D) and size (S) are an important adaptive mechanism for abiotic stress tolerance and photosynthesis capacity in rice. However, the genetic base of rice stomata-related traits still remains unclear. We identified quantitative trait loci (QTLs) associated with D and S on abaxial and adaxial leaf surfaces using genome-wide association analysis with 451 diverse accessions in two environments. D and S showed significant differences between indica (xian) and japonica (geng) accessions and significantly negative phenotypic correlations. A total of 64 QTLs influencing eight stomata-related traits were identified using 2,936,762 high-quality single nucleotide polymorphism markers. Twelve QTLs were consistently detected for the same traits in nine chromosomal regions in both environments. In addition, 12 QTL clusters were simultaneously detected for the same stomata-related traits on abaxial and adaxial leaf surfaces in the same environment, probably explaining the genetic bases of significant correlations of the stomata-related traits. We screened 64 candidate genes for the nine consistent QTL regions using haplotype analysis. Among them, LOC_Os01g66120 for qD ada 1, OsSPCH2 (LOC_Os02g15760) for qD ada 2.1 and qD aba 2.1, LOC_Os02g34320 for qS ada 2.2, OsFLP (LOC_Os07g43420) or LOC_Os07g43530 for qS aba 7.1, and LOC_Os07g41200 for qW ada 7 and qW aba 7 were considered as the most likely candidate genes based on functional annotations. The results systematically dissected the genetic base of stomata-related traits and provide useful information for improving rice yield potential via increasing abiotic stress tolerance and photosynthesis capacity under stressed and non-stressed conditions through deploying the favorable alleles underlying stomata-related traits by marker-assisted selection.