Indole-2-Carboxamide Derivative LG25 Inhibits Triple-Negative Breast Cancer Growth By Suppressing Akt/mTOR/NF-κB Signalling Pathway

Abstract

Background

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer which is associated with poor patient outcome and lack of targeted therapy. Our laboratory has synthesized a series of indole-2-carboxamide derivatives. Among this series, compound LG25 showed a favorable pharmacological profile against sepsis and inflammatory diseases. In the present study, we investigated the chemotherapeutic potential of LG25 against TNBC utilizing in vitro and in vivo models.

Methods

Changes in cell viability, cell cycle phases and apoptosis were analyzed using MTT, clonogenic assay, FACS and Western blotting assays. The anti-cancer effects of LG25 were further determined in a xenograft mouse model.

Results

Our findings reveal that LG25 reduced TNBC viability in a dose-dependent manner. Flow cytometric and Western blot analyses showed that LG25 enhances G2/M cell cycle arrest and induced cell apoptosis. In addition, LG25 treatment significantly inhibited Akt/mTOR phosphorylation and nuclear translocation of nuclear factor-κB (NF-κB). These inhibitory activities of LG25 were confirmed in mice implanted MDA-MB-231 TNBC cells.

Conclusion

Our studies provide experimental evidence that indole-2-carboxamide derivative LG25 effectively targeted TNBC in preclinical models by inducing cell cycle arrest and apoptosis, through suppressing Akt/mTOR/NF-κB signaling pathway.

Keywords:

• indole analog
• triple-negative breast cancer
• cell cycle arrest
• apoptosis
• Akt
• mTOR

Acknowledgments

Financial support was provided by the Natural Science Foundation of Zhejiang Province (LY17B020008 to Z.L., LR18H160003 to Y.W., LYI6H160050 to G.G.) for design of the study, collection, analysis and interpretation of data, and the National Natural Science Foundation of China (81750110549 to R.V. 81622043 to G.L.) for collection, analysis and interpretation of data, and writing of the manuscript.

Abbreviations

Bax, B-cell lymphoma-2 (Bcl-2) associated X protein; BC, breast cancer; Bcl-2, B-cell lymphoma-2; CDC-2, cell division cycle protein 2; ER, estrogen receptor; FACS, fluorescence-activated cell sorter; FBS, fetal bovine serum; FITC, fluorescein isothiocyanate; HER2, human epidermal growth factor receptor 2; LG25, 5-(furan-2-carboxamido)-N-(4-(4-methylpiperazin-1-yl)phenyl)-1-(4-(trifluoromethyl)benzyl)-1H-indole-2-carboxamide; MDM-2, murine double minute 2; mTOR, mammalian target of rapamycin; NF-κB, nuclear factor kappa-light-chain-enhancer of activated B cells; PI, propidium iodide; PR, progesterone receptor; PTX, Paclitaxel; S6RP, S6 ribosomal protein; TNBC, triple-negative breast cancer.

Availability Of Data And Material

All other data are included within the article and the supplementary materials, or available from the authors on request.

Author Contributions

G.G., G.L., and Y.W. participated in research design; X.X., V.R., Z.L., T.Y., and J.H. conducted experiments; S.S. and Z.L. contributed new reagents; X.X. and Y.W. performed data analysis; X.X. and Y.W. wrote the manuscript. All authors contributed to data analysis, drafting and revising the article, gave final approval of the version to be published, and agree to be accountable for the work.

Disclosure

The authors report no conflicts of interest in this work.