The chemokine receptor 7 (CCR7) and Snail signaling have been linked to various types of cancers. The associations between these signalings and the epithelial-mesenchymal transition (EMT) are not clear in gastric cancer. Here, the expression of CCR7 and Snail was detected in gastric cancer by immunohistochemistry and Western blot. Meanwhile, gastric cancer cells were subjected to CCL19, si-control, and si-Snail treatment. Cell cycle, migration, and invasion were also analyzed. The expression patterns of CCR7 and Snail were similar in either gastric cancer tissues or cells. The increased expression of CCR7 was closely associated with the increased Snail expression, which both were closely correlated with metastasis, stage and differentiation, and poor prognosis. The increased p-ERK, p-AKT, Snail, and MMP9 expression and the decreased E-cadherin were confirmed in MGC803 cells in a dose-dependent manner in response to CCL19 treatment. However, the blockade of Snail abrogated the up-regulation of MMP9 and down-regulation of E-cadherin. CCR7-induced ERK and PI3K pathway regulated Snail signaling. Besides si-Snail treatment led to MGC803 cell cycle arrest and affected the migration and invasion. In conclusion, our study suggested that CCR7 promotes Snail expression to induce the EMT, resulting in cell cycle progression, migration, and invasion in gastric cancer. CCR7-Snail pathway provided more potential regimens for cancer therapy.

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A dual‐band terahertz metamaterial absorber using one‐layer periodically patterned hexagon graphene structure is proposed. By periodically loading six graphene stubs to the honeycomb hexagon graphene structure without increase of the overall size, a new high‐frequency absorption peak will be obtained to realize a dual‐band frequency response. By tuning the structural parameters or Fermi energy levels of the presented terahertz metamaterial absorber, both of the two absorption bands will be changed to the required working frequencies for design specifications. Moreover, the proposed terahertz metamaterial absorber has the properties of polarization independence and incident angle insensitivity, which are of great significance in the applications of some detecting and sensing systems. This work will be a good candidate for the design guidance of various metamaterial absorbers using graphene with single or dual absorption bands.