The combination of thymoquinone and paclitaxel shows anti-tumor activity through the interplay with apoptosis network in triple-negative breast cancer.

Thymoquinone (TQ) is the active ingredient of Nigella sativa which has a therapeutic potential in cancer therapy and prevention. In this study, TQ has been shown to induce specific cytotoxicity and apoptosis and to inhibit wound healing in triple-negative breast cancer cell line. TQ also inhibited cancer growth in a mouse tumor model. Moreover, TQ and paclitaxel (Pac) combination inhibited cancer growth in cell culture and in mice. Genes involved in TQ and TQ-Pac-mediated cytotoxicity were studied using focused real-time PCR arrays. After bioinformatic analysis, genes in apoptosis, cytokine, and p53 signaling categories were found to be modulated with a high significance in TQ-treated cells (p < 10(-28), p < 10(-8), and p < 10(-6), respectively). Important to note, TQ has been found to regulate the genes involved in the induction of apoptosis through death receptors (p = 5.5 × 10(-5)). Additionally, tumor suppressor genes such as p21, Brca1, and Hic1 were highly upregulated by TQ and TQ-Pac combination. Interestingly, when cells were treated with high dose TQ, several growth factors such as Vegf and Egf were upregulated and several pro-apoptotic factors such as caspases were downregulated possibly pointing out key pathways manipulated by cancer cells to resist against TQ. In cells treated with the combination of TQ and Pac, genes in apoptosis cascade (p < 10(-12)), p53 signaling (p = 10(-5)), and JAK-STAT signaling (p < 10(-3)) were differentially expressed. TQ has also been shown to induce protein levels of cleaved Caspase-3, Caspase-7, and Caspase-12 and PARP and to reduce phosphorylated p65 and Akt1. The in vivo therapeutic potential of TQ-Pac combination and the genetic network involved in this synergy have been shown for the first time to the best of our knowledge.

Myrtucommulone-A Induces both Extrinsic and Intrinsic Apoptotic Pathways in Cancer Cells.

Myrtucommulone-A is the active compound derived from Myrtus communis. The molecular targets of myrtucommulone-A is widely unknown, which impedes its potential therapeutic use. In this study, we demonstrated the cytotoxicity of MC-A and its potential to induce apoptosis in cancer cells. Myrtucommulone-A was also found to be antiproliferative and strongly inhibited cancer cell migration. Eighty four apoptotic pathway genes were used to assess the effect of myrtucommulone-A on cancer cells. Myrtucommulone-A mediated an increase in apoptotic genes including Fas, FasL, Gadd45a, Tnf, Tnfsf12, Trp53, and caspase 4. The increase in myrtucommulone-A dose (25 µM versus 6.25 µM) also upregulated the expression of genes, which are involved mainly in apoptosis, regulation of apoptosis, role of mitochondria in apoptotic signaling, cytokine activity, and tumor necrosis factor signaling. Our data indicate that myrtucommulone-A could be utilized as a potential therapeutic compound with its molecular targets in apoptotic pathways.