Tetramethylpyrazine-Rhein Derivative inhibits the migration of canine inflammatory mammary carcinoma cells by mitochondrial damage-mediated apoptosis and cadherins downregulation

Abstract

BackgroundCanine inflammatory mammary carcinoma (CIMC) has a high incidence of metastasis, high lethality, and poor prognosis, which needs novel adjuvant agents. Tetramethylpyrazine-Rhein Derivative (TRD) has been shown to have antitumor activity, which is a potential research direction for CIMC. PurposeThis study evaluated the efficacy of TRD on CIMC in vitro and in vivo, and provided possibilities for the application of active compounds in traditional Chinese medicine. MethodsIn vitro, TRD cytotoxicity was measured with CCK-8. Flow cytometry and transmission electron microscope were used to detect the cell cycle, cell death, and changes in mitochondria. Wound-healing assay, cell invasion assay, and scanning electron microscope were used to evaluate the suppression of cell migration and invasion. Expression changes were detected by RT-qPCR and western blot assay. In vivo, the lung metastasis models were randomly divided into control, low-dose TRD, high-dose TRD, and positive groups. Each group was administered orally once a day for 18 days and took in vivo imaging photos. ResultsThe IC50 of TRD in CHMp and MDCK were 42.59 and 79.37 μM, respectively. TRD mediated cell apoptosis by mitochondrial damage and caused S and G2/M phase arrest by downregulating cyclin B1. Moreover, TRD reduced filopodia and inhibited cell migration by downregulating cadherins. In CIMC lung metastasis models, TRD could effectively inhibit tumor growth (P < 0.001) in the lungs without significant toxicity. ConclusionTRD showed potential activity to inhibit CIMC lung metastasis with multi-target and low toxicity.