Brazilein in Combination with Cisplatin Inhibit Proliferation and Migration on Highly Metastatic Cancer Cells, 4T1

Abstract

Brazilein performs anticancer activities on several cancer cells and potentially inhibits metastasis. The aims of this study is to observe the synergistic cytotoxic and migration inhibitory effect of brazilein combined with cisplatin on 4T1 breast cancer cells. Under MTT assay, we found that brazilein revealed cytotoxic effect on 4T1 cells in a dosedependent manner (IC 50 =50 ± 0.3 µM). Combination of brazilein and cisplatin showed synergistic effect (CI=0.72). Flowcytometry analysis on the cell cycle progression showed that single treatment of 25 µM brazilein induced G2/Mphase accumulation, 12.5 µM cisplatin induced Sphase accumulation, while combination of brazilein and cisplatin induced Sphase and G2/M phase accumulation. Combination of brazilein and cisplatin induced apoptosis higher than that of the single treatments. Based on wound healing assay, 12.5 µM brazilein and its combination with 6.25 µM cisplatin inhibited cells migration. Immunoblotting and gelatin zymography analysis showed that combination of brazilein and cisplatin inhibited the expression level of Rac1 and MMP9 proteins. Based on these results, we conclude that brazilein enhanced cytotoxic activity of cisplatin and inhibited migration on 4T1 cells and potentially can be developed as an enhancing cytotoxic and antimetastasis agent.

Optical Coherence Elastography for Non-Invasive Monitoring of Tumor Elasticity under Chemotherapy: Pilot Study

“…Thus, Li et al reported that after treatment by cisplatin in combination with doxorubicin, extensive areas of necrosis were observed in tumor cells; in other cells, various nuclear abnormalities -nuclear clamping and fragmentation -were revealed. Fragmentation of nuclei (karyorrhexis) may indicate the mechanism of apoptosis in tumor cells [32]. Other authors [32,33] also demonstrated an apoptotic response in 4T1 tumor cells exposed to cisplatin in vitro.…”

“…Fragmentation of nuclei (karyorrhexis) may indicate the mechanism of apoptosis in tumor cells [32]. Other authors [32,33] also demonstrated an apoptotic response in 4T1 tumor cells exposed to cisplatin in vitro. In our study, karyorrhexis was observed in tumors of the therapeutic group, which might indicate the mechanism of apoptotic cell death caused by cisplatin.…”

The Cytotoxic and Antimigratory Activity of Brazilin-Doxorubicin on MCF-7/HER2 Cells

“…Previous studies revealed antimigratory effects of the flavonoids brazilein and baicalein. 13 , 14 , 37 Secretion of MMP protein in the tumor microenvironment has a role in supporting migration and invasion of cancer cells through ECM degradation. 23 Our study shows the downregulation of MMP2 and MMP9 protein levels by treatment with brazilin alone and its combination with doxorubicin on HER2-overexpressing cells ( Figures 4 C and 4 D).…”

“…These data are in line with previous studies which showed that brazilein inhibits MMP2 on MDA-MB-231 cells and that its combination with cisplatin showed downregulation of MMP9 on 4T1 cells. 13 , 14 Other flavonoids, such as 7,7″-dimethoxyagastisflavone, luteolin, quercetin, and a curcumin analog (potassium pentagamavunon-0, K PGV-0), inhibit metastasis through suppression of MMP secretion. 38 - 40 Because NF-κB transcripts MMP protein 41 and HER2 protein has a role on NF-κB protein activation, 42 we drew an inference about the effect of inhibitory effects on migration and invasion by brazilin and its combination with doxorubicin on MCF-7/HER2 cells probably being related to the HER2/NF-κB pathway.…”

“… 12 Brazilein inhibits migration and invasion through suppression of Rac1 protein expression, as well as MMP2 and MMP9 activation and expression, on metastatic cancer cells. 13 , 14 Because HER2 involves NF-κB, Rac1, and MMP protein upregulation, the potential cytotoxic and antimetastatic effect of brazilin on HER2 pathway and brazilin’s potency as a co-chemotherapeutic agent need to be explored.…”