Mechanism of action of Panax notoginoside against lung cancer in mice based on response to CTSB gene

Background This study aimed to investigate the mechanism of action of Panax notoginoside (PNS) against lung cancer and inhibition of lung cancer cell proliferation by the drug at different concentrations in a mouse model, considering the cathepsin B ( CTSB ) gene as a target. Methods The mice were randomly assigned into the following five groups: normal control, tumor-bearing, low-dose Panax notoginoside (TSPN), medium-dose TSPN, and high-dose TSPN. All mice were treated with physiological saline or TSPN at different concentrations for 28 days consecutively by gavage. The tumor size was measured, the tumor growth was observed, and the survival curve was drawn. At different time points, the expression of the CTSB gene was detected using quantitative fluorescent polymerase chain reaction, Western blot analysis, and indirect immunofluorescence. The serum indices, such as carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and Soluble fragment of cytokeratin 19 (CYFRA21), were detected by enzyme-linked immunosorbent assay. Results In vivo, PNS could directly inhibit the expression of the CTSB gene in tumors of mice, limit tumor growth, and alter tumor-related indices, such as CEA, NSE, and CYFRA21 levels, in the serum to different extents simultaneously. Conclusion CTSB gene was closely related to the pathogenesis of lung cancer. PNS could act on the CTSB gene, downregulate the expression of CTSB in lung cancer cells, inhibit the proliferation and invasion of tumors, and prolong the survival period.