omega-hydroxyundec-9-enoic-acid and Breast-Neoplasms

This study was performed to evaluate the anticancer effect of ω-hydroxyundec-9-enoic acid (ω-HUA), a microbial bio-catalyst product in breast cancer cells, through AMP-activated protein kinase (AMPK) regulation. ω-HUA mediated apoptosis was induced in breast cancer cells by AMPK activation, loss of mitochondrial membrane potential, and reactive oxygen species (ROS) generation. ω-HUA treatment of breast cancer cells increased the AMPK phosphorylation levels, cleaved caspase-3, and poly (ADP-ribose) polymerase (PARP) proteins. In addition, anti-apoptotic members, such as Bcl-2, were downregulated, while Bax, a pro-apoptotic member, was upregulated. ω-HUA decreased the mitochondrial membrane potential while increasing the expression of cytochrome c (cyt c). Treating the cells with compound C, an AMPK inhibitor, reversed the phenomena, leading to an increase in cell viability and a decrease in apoptosis induction. Treating the cells with an ROS scavenger, N-acetyl cysteine (NAC), led to AMPK inactivation and apoptosis inhibition, allowing the recovery of cell health. In conclusion, ω-HUA sequentially caused the production of mitochondrial ROS and the consequent AMPK activation, thereby inducing apoptosis in breast cancer cells. Thus, ω-HUA may prove useful as an anticancer agent that targets AMPK in breast cancer cells.

Topics: AMP-Activated Protein Kinases; Antineoplastic Agents; Apoptosis; Breast Neoplasms; Cell Survival; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Mitochondria; Phosphorylation; Reactive Oxygen Species; Structure-Activity Relationship; Tumor Cells, Cultured; Undecylenic Acids

ω-Hydroxyundec-9-enoic acid (ω-HUA), a plant secondary metabolite, exhibits anti-fungal activity. However, its effect on breast cancer cells is unknown. Here, we investigated the anti- breast cancer activity of ω-HUA and its underlying mechanism. Treatment of human breast cancer cell lines, MDA-MB-231 and MDA-MB-435, with ω-HUA induced apoptotic cell death with increased cleaved caspase-3 and poly (ADP-ribose) polymerase (PARP) levels, and p38 and JNK phosphorylation. Inhibition of these mitogen-activated protein kinase (MAPK) pathways using specific inhibitors or siRNA, for p38 and JNK, respectively, blocked the ω-HUA-induced apoptosis in a dose-dependent manner. Moreover, pretreatment of the cells with antioxidant N-acetyl cysteine (NAC) inhibited ω-HUA-induced increased reactive oxygen species (ROS) levels, cleaved caspase-3 and cleaved PARP, and phosphorylated JNK, phosphorylated p38, and increased cell viability and colony-forming ability. MDA-MB-231 xenograft model showed that the ω-HUA-treated group exhibited greater tumor regression and significantly reduced tumor weight compared to that exhibited by the vehicle-administered group. Collectively, ω-HUA-induced intracellular ROS generation induced breast cancer cell apoptosis through JNK and p38 signaling pathway activation, resulting in tumor regression. The results suggested that ω-HUA is an effective supplement for inhibiting human breast cancer growth.

Topics: Animals; Antineoplastic Agents; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Female; Humans; MAP Kinase Kinase 4; Mice; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Reactive Oxygen Species; Undecylenic Acids; Xenograft Model Antitumor Assays