Anticancer Effects of α-Pinene in AGS Gastric Cancer Cells.

Gastric cancer is the fifth most common cancer globally and the third leading cause of cancer-related mortality. Existing treatment strategies for gastric cancer often present numerous side effects. Consequently, recent studies have shifted toward devising new treatments grounded in safer natural substances. α-Pinene, a natural terpene found in the essential oils of various plants, such as Lavender angustifolia and Satureja myrtifolia, displays antioxidant, antibiotic, and anticancer properties. Yet, its impact on gastric cancer remains unexplored. This research assessed the effects of α-pinene in vitro using a human gastric adenocarcinoma cell-line (AGS) human gastric cancer cells and in vivo via a xenograft mouse model. The survival rate of AGS cells treated with α-pinene was notably lower than that of the control group, as revealed by the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide assay. This decline in cell viability was linked to apoptosis, as verified by 4',6-diamidino-2-phenylindole and annexin V/propidium iodide staining. The α-pinene-treated group exhibited elevated cleaved-poly (ADP-ribose) polymerase and B cell lymphoma 2 (Bcl-2)-associated X (Bax) levels and reduced Bcl-2 levels compared with the control levels. Moreover, α-pinene triggered the activation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 within the mitogen-activated protein kinase (MAPK) pathway. In the xenograft mouse model, α-pinene induced apoptosis through the MAPK pathway, devoid of toxicity. These findings position α-pinene as a promising natural therapeutic for gastric cancer.

Dendropanax morbiferus H. Lév. Leaf Extract Inhibits the Proliferation of MDA-MB-231 Breast Cancer Cells and Induces Apoptosis via the MAPK Pathway In Vitro and In Vivo.

BACKGROUND/AIM: The toxic side effects of therapies against breast cancer can affect the quality of life of patients, necessitating the use of naturally-derived therapeutics. Here, we investigated the effects of Dendropanax morbiferus H. Lév. leaf (DPL) extract on breast cancer cells in vitro and in vivo to assess its anticancer potential. MATERIALS AND METHODS: MDA-MB-231 breast cancer cells were treated with DPL, and the in vitro effect of DPL on the cells was evaluated through an MTT assay, DAPI staining, annexin V/propidium iodide double staining, and western blotting. The in vivo effects of DPL were measured through the MDA-MB-231 tumor xenograft mouse model. A TUNEL assay and immunohistochemistry were used to determine the extent of apoptosis and p-p38 expression in tumor tissues, respectively. RESULTS: DPL treatment significantly suppressed cell viability in a concentration-dependent manner. Furthermore, DPL treatment resulted in increased apoptotic body formation, apoptosis rate, cleaved poly (ADP-ribose) polymerase and B-cell lymphoma 2 (Bcl-2)-associated X protein levels, phosphorylation of mitogen-activated protein kinase (MAPK) pathway proteins, and decreased Bcl-2 levels. In addition, the antitumor effect in vivo was confirmed through the xenograft model, where decreased tumor volume and weight following DPL administration were observed. Further, apoptosis and increased p-p38 levels in tumor tissues were observed, and no pathological abnormalities were found in the liver or kidney. CONCLUSION: DPL inhibits proliferation through MAPK-mediated apoptosis in breast cancer cells and tumors, suggesting the potential of DPL as a natural therapeutic agent for breast cancer.

Anticancer effects of oleanolic acid on human melanoma cells.

Owing to the ineffectiveness of the currently used therapies against melanoma, there has been a shift in focus toward alternative therapies involving the use of natural compounds. This study assessed the anticancer effects of oleanolic acid (OA) and its ability to induce apoptosis in A375SM and A375P melanoma cells in vivo. Compared to the control group, viability of A375P and A375SM cells decreased following OA treatment. In OA-treated A375SM and A375P cells, 4',6-diamidino-2-phenylindole staining showed an increase in the apoptotic body, and flow cytometry revealed increased number of apoptotic cells compared to that in the control group. OA-treated A375SM cells exhibited an increased expression of the apoptotic proteins, cleaved poly (ADP-ribose) polymerase (PARP) and B-cell lymphoma (Bcl)-2-associated X protein (Bax) as well as decreased expression of the antiapoptotic protein Bcl-2 compared to that in the control group. In OA-treated A375P cells, expression patterns of cleaved PARP and Bcl-2 were similar to those in OA-treated A375SM cells; however, no difference was reported in the expression of Bax compared to that in the control group. Additionally, OA-treated melanoma cells showed decreased expression of phospho-nuclear factor-κB (p-NF-κB), phospho-inhibitor of nuclear factor-κBα (p-IκBα), and phospho-IκB kinase αß than that in the control group. Moreover, immunohistochemistry showed a comparatively decreased level of p-NF-κB in the OA-treated group than that in the control group. Xenograft analysis confirmed the in vivo anticancer effects of OA against A375SM cells. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay revealed an increased number of TUNEL-positive cells in the OA-treated group compared to that in the control group. In conclusion, the study results suggest that OA induces apoptosis of A375SM and A375P cells in vitro and apoptosis of A375SM cells in vivo. Furthermore, the in vitro and in vivo anticancer effects were mediated by the NF-κB pathway.

Silymarin inhibits proliferation of human breast cancer cells via regulation of the MAPK signaling pathway and induction of apoptosis.

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.

Anti­inflammatory effects of Dendropanax morbifera in lipopolysaccharide­stimulated RAW264.7 macrophages and in an animal model of atopic dermatitis.

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 anti­inflammatory 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 interleukin­6, as well as the nuclear translocation of nuclear factor­κB (NF­κB). Additionally, the LPS­induced activation of extracellular signal­regulated kinase 1/2 (ERK1/2), P38 and c­Jun N­terminal kinase (JNK) was suppressed by DPL extract. Taken together, these results indicate that NF­κB, ERK1/2, P38 and JNK may be potential molecular targets of DPL extract in the LPS­induced inflammatory response. Subsequently, the present study investigated the effects of DPL extract in a 2,4­dinitrochlorobenzene­induced 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 anti­inflammatory potential and may be developed as a botanical drug to treat atopic dermatitis.

Ixeris dentata (Thunb. Ex Thunb.) Nakai Extract Inhibits Proliferation and Induces Apoptosis in Breast Cancer Cells through Akt/NF-κB Pathways.

Ixeris dentata (Thunb. Ex Thunb.) Nakai (ID) exhibits various physiological activities, and its related plant derived-products are expected to represent promising cancer therapeutic agents. However, the anticancer effects of ID extract on breast cancer cells classified as estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) are still unknown. In this study, we investigated the anti-cancer effects and analyzed the molecular mechanism of ID extract in T47D, MCF-7 (ER-, PR-positive, HER2-negative), SK-BR-3(ER-, PR-negative, HER2-positive), and MDA-MB-231 (Triple-negative) through in vitro studies. Additionally, we examined its anti-tumor effects through in vivo studies. Our findings indicated that ID extract-induced apoptosis was mediated via various survival pathways on four breast cancer cells by identifying the factors including Bcl-2 family, phospho-Akt and phospho-nuclear factor-κB (NF-κB). Based on in vitro findings that induced apoptosis via Akt-NF-κB signaling, we investigated the effects of ID extract on mice bearing MDA-MB-231 cells. The results showed that ID extract significantly decreased MDA-MB-231 tumor volume and weight via inducing apoptosis by suppressing phospho-Akt. Overall, these results indicate that ID extract induces apoptosis through the Akt-NFκB signaling pathway in MDA-MB-231 breast cancer cells and tumors, and it may serve as a therapeutic agent for triple-negative human breast cancer.

Anticancer effects of Ixeris dentata (Thunb. ex Thunb.) nakai extract on human melanoma cells A375P and A375SM.

ETHNOPHARMACOLOGICAL RELEVANCE: The plant species Taraxacum coreanum (TC), Youngia sonchifolia (YS), and Ixeris dentata (ID) belong to the family Compositae and are used for medicinal purposes in traditional medicine. However, the anticancer effects of TC, YS, and ID extracts and the underlying molecular mechanisms in melanoma cells have not been elucidated. AIM OF THE STUDY: To investigate the potential anticancer effects of TC, YS, and ID extracts on human melanoma cells and explore the potential pharmacological mechanisms in vitro and in vivo. MATERIALS AND METHODS: In this comparative study, we investigated the effects of TC, YS, and ID extracts on cell proliferation in human melanoma A375P and A375SM cells using MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays. Apoptotic cells were detected by 4',6-diamidino-2-phenylinodole (DAPI) staining. We also investigated whether the growth-inhibitory effects were associated with the induction of apoptosis and whether the mechanisms of cell death were the result of signaling molecules such as p53, Bax, Bcl-2, caspase-9, Poly-ADP ribose polymerase (PARP), and Erk (Extracellular signal-regulated protein kinase) 1/2. The in vivo antitumor effects were evaluated by measuring the tumor volume and weight and performing Terminal deoxynucleotidyl transferase (TdT) dUTP Nick End Labeling (TUNEL) assay and immunohistochemistry (IHC) in tumor xenograft models. RESULTS: TC, YS, and ID extracts effectively inhibited the growth of A375P and A375SM cells. In addition, several apoptotic events were observed following treatment, including DNA fragmentation and chromatin condensation by DAPI staining. The extracts increased p53, Bax, cleaved-caspase-9 and cleaved-PARP expression, whereas the expression of Bcl-2 was decreased in both cell lines. Furthermore, ID extract significantly inhibited the activation of Erk1/2 in both cell lines. Among the three extracts, ID had the strongest apoptotic effects. The administration of ID extract to mice inhibited tumor growth without any toxicity following 4 weeks of treatment. This extract increased the expression of apoptotic cells and p53 protein and decreased phospho-Erk1/2 protein. CONCLUSION: TC, YS, and ID extracts suppress the growth of human melanoma cells through apoptosis. Among these extracts, ID has the strongest anticancer and apoptotic effects. It induces apoptosis through the inhibition of Erk1/2 in A375P and A375SM human melanoma cells and in tumor xenograft models and may be a potential chemotherapeutic agent against melanoma.

Antitumor and apoptosis-inducing effects of α-mangostin extracted from the pericarp of the mangosteen fruit (Garcinia mangostana L.)in YD-15 tongue mucoepidermoid carcinoma cells.

α-mangostin is a dietary xanthone which has been shown to have antioxidant, anti-allergic, antiviral, antibacterial, anti-inflammatory and anticancer effects in various types of human cancer cells. In the present study, we aimed to elucidate the molecular mechanisms responsible for the apoptosis-inducing effects of α-mangostin on YD-15 tongue mucoepidermoid carcinoma cells. The results from MTT assays revealed that cell proliferation significantly decreased in a dose-dependent manner in the cells treated with α-mangostin. DAPI staining illustrated that chromatin condensation in the cells treated with 15 µM α-mangostin was far greater than that in the untreated cells. Flow cytometric analysis indicated that α-mangostin suppressed YD-15 cell viability by inducing apoptosis and promoting cell cycle arrest in the sub-G1 phase. Western blot analysis of various signaling molecules revealed that α-mangostin targeted the extracellular signal­regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK) signaling pathways through the inhibition of ERK1/2 and p38 phosphorylation in a dose­dependent manner. α-mangostin also increased the levels of Bax (pro-apoptotic), cleaved caspase-3, cleaved caspase-9 and cleaved-poly(ADP-ribose) polymerase (PARP), whereas the levels of the anti-apoptotic factors, Bcl-2 and c-myc, decreased in a dose-dependent manner. The anticancer effects of α-mangostin were also investigated in a tumor xenograft mouse model. The α-mangostin-treated nude mice bearing YD-15 tumor xenografts exhibited a significantly reduced tumor volume and tumor weight due to the potent promoting effects of α-mangostin on cancer cell apoptosis, as determined by TUNEL assay. Immunohistochemical analysis revealed that the level of cleaved caspase-3 increased, whereas the Ki-67, p-ERK1/2 and p-p38 levels decreased in the α-mangostin­treated mice. Taken together, the findings of our study indicate that α-mangostin induces the apoptosis of YD-15 tongue carcinoma cells through the ERK1/2 and p38 MAPK signaling pathways.

Targeting ERK1/2-bim signaling cascades by BH3-mimetic ABT-737 as an alternative therapeutic strategy for oral cancer.

To date, many different chemotherapeutic agents have been widely used as common treatments for oral cancers. However, their therapeutic effects have been disappointing, and these agents may have unwanted side effects. Among the many regulatory factors, overexpression of pro-survival Bcl-2 family members may promote resistance to chemotherapeutic drugs in many tumors. The BH3 domain-only proteins effectively antagonize their apoptotic activities. Therefore, there is substantial interest in developing chemotherapeutic drugs that directly target pro-survival Bcl-2 proteins by mimicking the BH3 domain and unleashing pro-apoptotic molecules in tumor cells. Among the numerous available small molecule BH3 mimetics, ABT-737, a potent small molecule that binds to Bcl-2/Bcl-xL with high affinity, has anti-tumor activity in a wide variety of cancer cells. However, the effects of ABT-737 on human oral cancers and the underlying molecular mechanisms have not previously been elucidated. In the present study, we observed that inactivation of the ERK1/2 signaling pathway using ABT-737 dramatically increased the expression of pro-apoptotic protein Bim via transcriptional and/or posttranslational regulation, in a cell type-dependent manner, inducing mitochondria-mediated apoptosis of human oral cancer cells. To the best of our knowledge, this is the first demonstration of the antitumor effects of ABT-737 on human oral cancers.

Effect of water-soluble silicon supplementation on bone status and balance of calcium and magnesium in male mice.

Silicon (Si) is important for the growth and development of bone and connective tissues. Several studies have reported that Si supplementation improved bone mineral density (BMD) in female ovarectomized rats. However, few studies have investigated the effects of Si supplementation on bone status and bone metabolism in male animals. The purpose of this study was to investigate the effects of Si supplementation on BMD and balance of calcium (Ca) and magnesium (Mg) in adult male mice. Si was administrated orally through demineralized water containing different contents of Si as a form of sodium metasilicate (0 %, control; 0.025 %, Si50; 0.050 %, Si100; and 0.075 %, Si150) to 9-week-old male mice for 4 weeks. Si supplementation did not alter weight gain or BMD of femur and tibia in male mice. However, a high level of Si (0.05 and 0.075 %) supplementation significantly decreased Mg retention without changing Ca retention. Serum alkaline phosphatase of Si-supplemented groups significantly decreased compared with that of the control. According to these results, short-term Si supplementation did not affect BMD but showed a possible effect on increasing the need for Mg in adult male mice.

Apoptotic effect of hot water extract of Sanguisorba officinalis L. in human oral cancer cells.

Sanguisorba officinalis L. has been used in traditional Asian medicine to treat diseases including diarrhea, chronic intestinal infections, duodenal ulcers and bleeding. This study examined the antiproliferative effects and apoptotic activity of hot water extract of S. officinalis L. (HESO) on HSC4 and HN22 human oral cancer cells. The effects of HESO were evaluated by the 3-(4,5-dimethylthiazol-20yl)-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay, 4'-6-diamidino-2-phenylindole (DAPI) staining and western blot analysis. HESO was found to inhibit cell growth and induce apoptosis in HSC4 and HN22 oral cancer cells. HESO downregulated myeloid cell leukemia-1 (Mcl-1) in HSC4 cells and was associated with the activation of Bak, resulting in Bak oligomerization on the mitochondrial outer membrane. HESO did not alter Mcl-1 expression in HN22 cells, but it decreased Sp1 expression. The downregulation of Sp1 by HESO in HN22 cells resulted in a decrease in survivin, a downstream target protein of Sp1. These results suggested that HESO inhibited the growth of oral cancer through either Mcl-1 or Sp1, indicating that HESO may serve as a potential drug candidate against oral cancer.

Apoptotic effect of quercetin on HT-29 colon cancer cells via the AMPK signaling pathway.

Activation of AMP-activated protein kinase (AMPK), a physiological cellular energy sensor, strongly suppresses cell proliferation in both nonmalignant and tumor cells. This study demonstrates the mechanism of quercetin-induced apoptosis in HT-29 colon cancer cells. Treatment of cells with quercetin significantly decreased cell viability in a dose-dependent manner. Notably, quercetin increased cell cycle arrest in the G1 phase and up-regulated apoptosis-related proteins, such as AMPK, p53, and p21, within 48 h. Furthermore, in vivo experiments showed that quercetin treatment resulted in a significant reduction in tumor volume over 6 weeks, and apoptosis-related protein induction by quercetin was significantly higher in the 100 mg/kg treated group compared to the control group. All of these results indicate that quercetin induces apoptosis via AMPK activation and p53-dependent apoptotic cell death in HT-29 colon cancer cells and that it may be a potential chemopreventive or therapeutic agent against HT-29 colon cancer.