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Tanshinone IIA (Tan IIA) and sinapic acid (SA) are 2 components separately isolated from 2 Asian medicinal plants, Hydnophytum formicarum Jack and Salvia miltiorrhiza Bunge. The antitumor activities of them were worth exploring, therefore, we examined their antitumor activities in A549, HCT116, HeLa, and Colo320 cancer cell lines by means of WST-1 assay. The results show that Tan IIA exerted far higher (IC50 from 1.0 ± 0.0 to 166.3 ± 24.0 µg/mL) antiproliferative activities than SA (IC50 from 2236.3 ± 484.1 to >10 000.0 µg/mL). Of the 4 cell lines, A549 cells were the most sensitive to Tan IIA; thus, we used Western blotting to explore the cytotoxic mechanisms of Tan IIA in A549 cells and found that they rely on simultaneous induction of apoptosis and necroptosis in the cells. Apoptosis was hallmarked by the induction of cleaved caspase-3 by Tan IIA and necroptosis by the necroptotic marker proteins cyclophilin A and high mobility group box 1 (HMGB1), as well as increased lactate dehydrogenase (LDH) activities. The necroptotic effect was confirmed by the necroptosis inhibitor necrostatin-1 (Nec-1), which eliminated these effects and restored cell survival rates. The levels of cyclophilin A decreased in response to the pan-caspase inhibitor z-VAD-fmk, and those of cleaved caspase-3 decreased in response to Nec-1. Conclusively, Tan IIA has the potential to prevent lung cancer and the mechanism seems to be apoptosis and necroptosis, of which the relationship is mutually interdependent. This is the first report of Tan IIA eliciting necroptosis in A549 cells. Tan IIA may be used for necroptosis-based cancer therapy, especially to overcome apoptosis resistance.

High-grade serous ovarian carcinoma (HGSOC) originates mainly from the fallopian tube (FT) epithelium and always carries early TP53 mutations. We previously reported that tumors initiate in the FT fimbria epithelium because of apoptotic failure and the expansion of cells with DNA double-strand breaks (DSB) caused by bathing of the FT epithelial cells in reactive oxygen species (ROSs) and hemoglobin-rich follicular fluid (FF) after ovulation. Because ovulation is frequent and HGSOC is rare, we hypothesized that luteal-phase progesterone (P4) could eliminate p53-defective FT cells. Here we show that P4, via P4 receptors (PRs), induces necroptosis in Trp53-/- mouse oviduct epithelium and in immortalized human p53-defective fimbrial epithelium through the TNF-α/RIPK1/RIPK3/MLKL pathway. Necroptosis occurs specifically at diestrus, recovers at the proestrus phase of the estrus cycle, and can be augmented with P4 supplementation. These results reveal the mechanism of the well-known ability of progesterone to prevent ovarian cancer.

Tanshinone IIA (Tan IIA), a constituent of the traditional medicinal plant Salvia miltiorrhiza BUNGE, has been reported to possess anticancer activity through induction of apoptosis in many cancer cells. Surprisingly, the present study finds that Tan IIA simultaneously causes apoptosis and necroptosis in human hepatocellular carcinoma HepG2 cells. We further find that apoptosis can be converted to necroptosis by pan-caspase inhibitor Z-VAD-fmk, and the two death modes can be blocked by necroptotic inhibitor necrostatin-1. The underlying mechanisms are revealed by analysis of the signaling molecules using western blotting. In control cells, FLICE inhibitory protein in short form (FLIPS) is expressed in relatively high levels and binds to caspase 8 in ripoptosome, which supposedly sustains cell survival. However, in Tan IIA-treated cells, FLIPS is down-regulated and may thus cause homodimer formation of cleaved caspase 8, cleavage of receptor-interacting serine/threonine-protein kinases 1, 3 (RIP1, RIP3), and mixed-lineage kinase domain-like (MLKL), in turn leads to cell apoptosis. In parallel, Tan IIA causes necroptosis by forming a suggested necrosomal complex composed of RIP1/RIP3. Regarding the inhibitors, z-VAD-fmk diminishes the cleaved caspase 8, RIP1, RIP3, and MLKL induced by Tan IIA, and reconstructs the ripoptosome complex, which marks cells moving from apoptosis to necroptosis. Nec-1 recovers the Tan IIA down-regulated FLIPS, consequently causes FLIPS to form heterodimer with caspase 8 and thus block apoptosis. Meanwhile, cleaved forms of RIP1 and RIP3 were observed preventing necroptosis. Intriguingly, the cytotoxicity of tumor necrosis factor-related apoptosis-inducing ligand to HepG2 cells is enhanced by Tan IIA in a pilot study, which may be attributed to low FLIPS levels induced by Tan IIA. In short, Tan IIA simultaneously induces both Nec-1 inhibition and FLIPS regulation-mediated apoptosis/necroptosis, which has not been previously documented. Moreover, the involvement of the cleavage type of MLKL in executing necroptosis warrants further investigation.

To determine the combinative effects of tanshinone IIA (Tan IIA) and trans-resveratrol (Resv) on cytotoxicity, apoptosis, cell-cycle arrest and DNA fragmentation in HepG2 human liver cancer cells.Cytotoxicity was detected by the cell proliferation and cytotoxicity WST-1 assay. Cell-cycle arrest and apoptosis were determined using flow cytometry analysis. DNA fragments were separated by gel electrophoresis.Tan IIA and Resv at mixture ratios of 1/2:1/2 and 1/3:2/3 exerted synergistic cytotoxicity comparable to that of cisplatin. Elevated proportions of sub-G1 and apoptotic cells were respectively found in the combinative treatments in comparison with hypothetic values of additive effects. Moreover, a more intensive pattern of apoptotic DNA fragmentation was visualized in combined treatments than in individual ones.Combining Tan IIA and Resv causes synergistic cisplatin-comparable, cytotoxicity and robustly induces apoptosis, sub-G1 cell cycle arrest and DNA fragmentation. This study provides evidence supporting further pre-clinical investigations of the combinational synergism.

This study evaluated supercritical fluid extraction (SFE) combined with liquid chromatography-mass spectrometry (LC-MS) to determine trace preservatives and antioxidants including methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BP), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol (alpha-t) and alpha-tocopherol acetate (alpha-ta) in cosmetic products. A supercritical fluid extraction procedure was used to isolate four paraben preservatives and four antioxidants from the cosmetic matrix before quantitative analysis. The optimum extraction condition was performed with static extraction for 5 min, then dynamic extraction for 20 min by using carbon dioxide supercritical fluid at 14,000 kPa and 65 degrees C. Methanol was used as collection solvent and the sea sand was chosen as a filling material. The analytes were separated on a C18 reversed-phase column using methanol-water as mobile phase and quantified by measuring its mass spectrometry. The linearity range is from 10 to 20,000 ng/g with RSD values below 18%. Detection limits are achieved at the level of 4.7-142 ng/g. It was successfully applied to the determination of paraben preservatives and antioxidants in cosmetics without tedious pretreatment.