Excellent Anti-lung Cancer Activity of Populus nigra and Phylogenetic Analysis

Lung cancer has the highest incidence rate among malignant tumors all over the world, and it is also the leading cause of death. In this present research, we aimed to evaluate the anti-cancer activity of the Populus nigra extract against the lung cancer and study the genome evolution of the Populus nigra. Firstly, the inhibitory activity of the Populus nigra extract on the NCI-H292 lung cancer cell viability was determined with Cell Counting Kit-8 (CCK-8) assay. The trans-well assay was conducted and the influence of the Populus nigra extract on the NCI-H292 lung cancer cell migration and invasion ability was determined. In addition to this, the chloroplast (cp) genome of Populus nigra was sequenced with high-throughput Illumina pair-end sequencing, which was a classical useful model for genome evolution assessment. The CCK-8 and trans-well assay indicated the Populus nigra extract exhibited excellent inhibitory activity on the NCI-H292 lung cancer cell viability, migration and invasion ability. The circular cp genome of the Populus nigra was 156,354 bp in size, including a large single-copy (LSC) region of 84,528 bp and a small single-copy (SC) region of 16,564 bp, which were separated by two inverted repeat (IR) regions (38,612 bp each). A total of 132 genes were predicted, including 8 ribosomal RNAs (rRNAs), 37 transfer RNAs (tRNAs), and 90 protein-coding genes (PCGs). Furthermore, phylogenetic analysis revealed that Populus nigra has the closest relationship with Populus alba var. pyramidalis. In addition to Populus alba var. pyramidalis, Populus adenopoda and Populus tomentosa are also has closely relationship with Populus nigra.