The canine mammary
tumor model is more suitable for studying human
breast cancer, and the safety concentrations of
matrine and the
biotin-labeled
matrine probe were determined in canine primary mammary epithelial cells, and then selected canine mammary tumor cell lines CHMm and CHMp were incubated with
matrine, and cell viability was detected by
CCK-8. The
biotin-labeled
matrine probe was used to pull-down the targets of
matrine in canine mammary
tumor cells, and the targets were screened in combination with activity-based
protein profiling (ABPP) and Genecards database, and verified by qPCR and western blot. The results showed that the maximum non-cytotoxic concentrations of
matrine and
biotin-labeled
matrine probe in canine primary mammary epithelial cells were 250 μg/mL and 500 μg/mL, respectively.
Matrine and
biotin-labeled
matrine probe had a proliferation inhibitory effect time-dependently on CHMm and CHMp cells within a safe concentration range, and induced autophagy in cells. Then BTF3 targets were obtained by applying ABPP and Genecards screening. Cellular thermal shift assay (CETSA) findings indicated that
matrine could increase the heat stability of BTF3
protein. Pull-down employing
biotin-labeled
matrine probe with CHMm and CHMp cell lysates revealed that BTF3
protein was detected in the
biotin-labeled
matrine probe group and that BTF3
protein was significantly decreased by the addition of
matrine. The qPCR and western blot findings of CHMm and CHMp cells treated with
matrine revealed that
matrine decreased the expression of the BTF3 gene and
protein with the extension of the action time, and the impact was more substantial at the
protein level, respectively.