In this study, we showed that PI3K/Akt signaling mediates fucoidan’s anticancer effects on prostate cancer cells, including suppression of proliferation. Fucoidan significantly decreased viability of DU-145 cancer cells in a concentration-dependent manner as shown by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The drug also significantly increased chromatin condensation, which indicates apoptosis, in a concentration-dependent manner as shown by DAPI (4′,6-diamidino-2-phenylindole) staining. Fucoidan increased expression of Bax, cleaved poly-ADP ribose polymerase and cleaved caspase-9, and decreased of the Bcl-2, p-Akt, p-PI3K, p-P38, and p-ERK in a concentration-dependent manner. In vivo, fucoidan (at 5 and 10 mg/kg) significantly decreased tumor volume, and increased apoptosis as assessed by the TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay, confirming the tumor inhibitory effect. The drug also increased expression of p-Akt and p-ERK as shown by immunohistochemistry staining. Therefore, fucoidan may be a promising cancer preventive medicine due to its growth inhibitory effects and induction of apoptosis in human prostate cancer cells.

Apoptosis is regarded as a therapeutic target because it is typically disturbed in human cancer. Silymarin from milk thistle (Silybum marianum) has been reported to exhibit anticancer properties via regulation of apoptosis as well as anti-inflammatory, antioxidant and hepatoprotective effects. In the present study, the effects of silymarin on the inhibition of proliferation and apoptosis were examined in human gastric cancer cells. The viability of AGS human gastric cancer cells was assessed by MTT assay. The migration of AGS cells was investigated by wound healing assay. Silymarin was revealed to significantly decrease viability and migration of AGS cells in a concentration-dependent manner. In addition, the number of apoptotic bodies and the rate of apoptosis were increased in a dose-dependent manner as determined by DAPI staining and Annexin V/propidium iodide double staining. The changes in the expression of silymarin-induced apoptosis proteins were investigated in human gastric cancer cells by western blotting analysis. Silymarin increased the expression of Bax, phosphorylated (p)-JNK and p-p38, and cleaved poly-ADP ribose polymerase, and decreased the levels of Bcl-2 and p-ERK1/2 in a concentration-dependent manner. The in vivo tumor growth inhibitory effect of silymarin was investigated. Silymarin (100 mg/kg) significantly decreased the AGS tumor volume and increased apoptosis, as assessed by the TUNEL assay, confirming its tumor-inhibitory effect. Immunohistochemical staining revealed elevated expression of p-JNK and p-p38 as well as reduced expression of p-ERK1/2 associated with silymarin-treatment. Silymarin was revealed to reduce tumor growth through inhibition of p-ERK and activation of p-p38 and p-JNK in human gastric cancer cells. These results indicated that silymarin has potential for development as a cancer therapeutic due to its growth inhibitory effects and induction of apoptosis in human gastric cancer cells.

apigenin, an aromatic compound, exhibits antioxidant, anti-inflammatory and anti-viral effects. The present study aimed to investigate the effects of apigenin on cell proliferation and apoptosis of human melanoma cells A375P and A375SM. Therefore, melanoma cells were treated with apigenin to determine its anti-proliferative and survival effects, using wound healing and MTT assays. The results revealed that melanoma cell viability was decreased in a dose-dependent manner. Furthermore, chromatin condensation, indicating apoptosis, was significantly increased in a dose-dependent manner, as demonstrated by DAPI staining. In addition, increased apoptosis rate following treatment with apigenin was confirmed by Annexin V-propidium iodide staining. The changes in the expression levels of apoptosis-related proteins in A375P and A375SM melanoma cells were subsequently detected using western blot analysis. The results demonstrated that the protein expression levels of Bcl-2 were decreased, whereas those of Bax, cleaved poly ADP-ribose polymerase, cleaved caspase-9 and p53 were upregulated in a dose-dependent manner in apigenin-treated cells compared with those noted in untreated cells. In addition, in apigenin-treated A375P cells, phosphorylated (p)-p38 was upregulated and p-extracellular signal-regulated kinase (ERK), p-c-Jun N-terminal kinase (JNK) and p-protein kinase B (Akt) were downregulated. However, in A375SM cells, apigenin treatment increased pERK and p-JNK and decreased p-p38 and p-Akt protein expression levels. Subsequently, the inhibitory effect of apigenin on tumor growth was investigated in vivo. Tumor volume was significantly reduced in the 25 and 50 mg/kg apigenin-treated groups compared with the control group. Additionally, a TUNEL assay was performed to detect apoptotic cells. Immunohistochemical staining also revealed elevated pERK expression in the apigenin-treated group compared with the control group. Overall, the findings of the present study indicated that apigenin attenuated the growth of A375SM melanoma cells by inducing apoptosis via regulating the Akt and mitogen-activated protein kinase signaling pathways.

Dendropanax morbifera ( D. morbifera ), known as Dendro, means ‘omnipotent drug’ (Panax), and has been called the panacea tree. Various studies on D. morbifera are currently ongoing, aiming to determine its medicinal uses. The present study investigated the anti-inflammatory effects and underlying mechanism of a natural extract of D. morbifera leaves (DPL) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. In the present study, the following assays and models were used: MTT assay, nitric oxide (NO) assay, western blotting, ELISA and mouse models of atopic dermatitis. DPL extract markedly reduced the production of NO, inducible NO synthase and interleukin-6, as well as the nuclear translocation of nuclear factor-κB (NF-κB). Additionally, the LPS-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2), P38 and c-Jun N-terminal kinase (JNK) was suppressed by DPL extract. Taken together, these results indicate that NF-κB, ERK1/2, P38 and JNK may be potential molecular targets of DPL extract in the LPS-induced inflammatory response. Subsequently, the present study investigated the effects of DPL extract in a 2,4-dinitrochlorobenzene-induced atopic dermatitis mouse model. Ear thickness, serum immunoglobulin E levels and histological analysis revealed that the DPL extract was effective in attenuating the inflammatory response. These results indicate that DPL extract has anti-inflammatory potential and may be developed as a botanical drug to treat atopic dermatitis.

Silymarin is a purified mixture of four isomeric flavonoids extracted from the seeds and fruit of the milk thistle plant, Silybum marianus (L.). Silymarin exhibits a wide variety of biological effects and is commonly used in traditional medicine. Therefore, the anticancer effects of silymarin on human breast cancer cells were investigated to determine its pharmacological mechanisms in vitro and in vivo. The viability and proliferation of MDA-MB-231 and MCF-7 breast cancer cells were investigated using MTT and wound healing assays. Silymarin decreased the viability and proliferation of MDA-MB-231 and MCF-7 cells in a concentration-dependent manner. The number of apoptotic bodies, as shown by DAPI staining, was increased in a concentration-dependent manner, indicating that silymarin induces apoptosis. Additionally, changes in the expression levels of apoptosis-related proteins were demonstrated in human breast cancer cells using western blotting. Silymarin increased the levels of Bax, cleaved poly-ADP ribose polymerase, cleaved caspase-9 and phosphorylated (p-)JNK, and decreased the levels of Bcl-2, p-P38 and p-ERK1/2. Furthermore, the inhibitory effects of silymarin on MCF-7 tumor growth were investigated. In mice treated with silymarin for 3 weeks (25 and 50 mg/kg), MCF-7 tumor growth was inhibited without organ toxicity. In MCF-7 tumors, silymarin induced apoptosis and decreased p-ERK1/2 levels, as assessed using a TUNEL assay and immunohistochemistry. These results indicated that silymarin inhibited breast cancer cell proliferation both in vitro and in vivo by modulating the MAPK signaling pathway. Therefore, silymarin may potentially be used as a chemo-preventive or therapeutic agent.