ABSTRACT
Breast cancer remains one of the leading causes of cancer related deaths in women worldwide. Bharangin is a diterpenoid quinonemethide that has demonstrated therapeutic potential against leukemia, lymphoma, and multiple myeloma cells. Whether this diterpenoid exhibit activities against breast cancer cells and the underlying mechanism is largely unknown. Herein, we provide evidence that bharangin suppresses the proliferation of MCF-7, MDA-MB-231, MDA-MB-453, MDA-MB-468 and T-47D breast cancer cells. As examined by AO/PI staining, DAPI staining, sub-G1 analysis, phosphatidylserine externalization, caspase activation, DNA laddering, and poly-ADP ribose polymerase cleavage, the diterpenoid induced apoptosis in breast cancer cells. The growth inhibitory effect of bharangin on breast cancer cells was further confirmed from colony-formation assay. Furthermore, the cancer cell migration was also suppressed by the diterpenoid. Mechanistically, bharangin was found to modulate multiple cancer related cell signalling pathways in breast cancer cells. Bharangin suppressed the expression of cell survival and invasive proteins, and induced Bax and mitochondrial depolarization in breast cancer cells. The diterpenoid also suppressed the activation of pro-inflammatory transcription factor, nuclear factor (NF)-κB induced by okadaic acid. Finally, the diterpenoid induced the expression of tumor suppressor lncRNAs (MEG-3, GAS-5), while down-regulating oncogenic H19 expression. Overall, these results suggest that bharangin exhibits anti-carcinogenic, anti-proliferative and anti-inflammatory activities against breast cancer cells. The modulation of lncRNA expression and inhibition of NF-κB activation by bharangin may contribute to its anti-carcinogenic activities.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Breast Neoplasms/pathology , Flavonoids/pharmacology , NF-kappa B/physiology , RNA, Long Noncoding/physiology , Apoptosis/drug effects , Breast Neoplasms/enzymology , Breast Neoplasms/genetics , Breast Neoplasms/physiopathology , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Humans , Poly (ADP-Ribose) Polymerase-1/metabolism , Signal Transduction/drug effectsABSTRACT
Epoxyazadiradione (EAD) is an important limonoid present in Neem (Azadirachta indica) plant. In the present study, we have purified EAD from Neem seed and studied its anticancer potential in human cervical cancer (HeLa) cells. Cell proliferation inhibition studies indicated that the GI50 value of EAD is 7.5 ± 0.0092 µM in HeLa cells, whereas up to 50 µM concentrations EAD did not affect the growth of normal H9C2 cells. The control drug cisplatin inhibited the growth of both HeLa and H9C2 cells with a GI50 value of 2.92 ± 1.192 and 4.22 ± 1.568 µM, respectively. Nuclear DNA fragmentation, cell membrane blebbing, phosphatidylserine translocation, upregulation of Bax, caspase 3 activity and poly (ADP ribose) polymerase cleavage and downregulation of BCl2 in HeLa cells on treatment with EAD indicated the apoptotic cell death. Increase in caspase 9 activity and release of active cytochrome c to the cytoplasm on treatment with EAD confirmed that the apoptosis was mediated through the mitochondrial pathway. Epoxyazadiradione also inhibited the nuclear translocation of nuclear factor κB in HeLa cells. Thus, our studies demonstrated EAD as a potent and safe chemotherapeutic agent when compared with the standard drug cisplatin that is toxic to both cancer and normal cells equally. Copyright © 2017 John Wiley & Sons, Ltd.
