SH003 Causes ER Stress-mediated Apoptosis of Breast Cancer Cells via Intracellular ROS Production.

BACKGROUND/AIM: Breast cancer is one of the most common cancers in women all over the world and new treatment options are urgent. ER stress in cancer cells results in apoptotic cell death, and it is being proposed as a new therapeutic target. SH003, a newly developed herbal medicine, has been reported to have anti-cancer effects. However, its molecular mechanism is not yet clearly defined. MATERIALS AND METHODS: Microarray was performed to check the differential gene expression patterns in various breast cancer cell lines. Cell viability was measured by MTT assays to detect cytotoxic effects. Annexin V-FITC and 7AAD staining, TUNEL assay and DCF-DA staining were analyzed by flow cytometry to evaluate apoptosis and ROS levels, respectively. Protein expression was examined in SH003-breast cancer cells using immunoblotting assays. The expression of C/EBP Homologous Protein (CHOP) mRNA was measured by real-time PCR. The effects of CHOP by SH003 treatment were investigated using transfection method. RESULTS: Herein, we investigated the molecular mechanisms through which SH003 causes apoptosis of human breast cancer cells. Both cell viability and apoptosis assays confirmed the SH003-induced apoptosis of breast cancer cells. Meanwhile, SH003 altered the expression patterns of several genes in a variety of breast cancer cell lines. More specifically, it upregulated gene sets including the response to unfolded proteins, independently of the breast cancer cell subtype. In addition, SH003-induced apoptosis was due to an increase in ROS production and an activation of the ER stress-signaling pathway. Moreover, CHOP gene silencing blocked SH003-induced apoptosis. CONCLUSION: SH003 causes apoptosis of breast cancer cells by upregulating ROS production and activating the ER stress-mediated pathway. Thus, our findings suggest that SH003 can be a potential therapeutic agent for breast cancer.

SH003 and Docetaxel Show Synergistic Anticancer Effects by Inhibiting EGFR Activation in Triple-Negative Breast Cancer.

Although many anticancer drugs have been developed for triple-negative breast cancer (TNBC) treatment, there are no obvious therapies. Moreover, the combination of epidermal growth factor receptor- (EGFR-) targeted therapeutics and classical chemotherapeutic drugs has been assessed in clinical trials for TNBC treatment, but those are not yet approved. Our serial studies for newly developed herbal medicine named SH003 provide evidence of its broad effectiveness in various cancers, especially on TNBC. The current study demonstrates a synergic effect of combinatorial treatment of SH003 and docetaxel (DTX) by targeting EGFR activation. The combinatorial treatment reduced the viability of both BT-20 and MDA-MB-231 TNBC cells, displaying the synergism. The combination of SH003 and DTX also caused the synergistic effect on apoptosis. Mechanistically, the cotreatment of SH003 and DTX inhibited phosphorylation of EGFR and AKT in both BT-20 and MDA-MB-231 cells. Moreover, our xenograft mouse tumor growth assays showed the inhibitory effect of the combinatorial treatment with no effect on body weight. Our immunohistochemistry confirmed its inhibition of EGFR phosphorylation in vivo. Collectively, combinatorial treatment of SH003 and DTX has a synergistic anticancer effect at a relatively low concentration by targeting EGFR in TNBC, indicating safety and efficacy of SH003 as adjuvant combination therapy with docetaxel. Thus, it is worth testing the combinatorial effect in clinics for treating TNBC.

Synergistic Antitumor Activity of SH003 and Docetaxel via EGFR Signaling Inhibition in Non-Small Cell Lung Cancer.

Epidermal growth factor receptor (EGFR) is overexpressed in lung cancer patients. Despite treatment with various EGFR tyrosine kinase inhibitors, recurrence and metastasis of lung cancer are inevitable. Docetaxel (DTX) is an effective conventional drug that is used to treat various cancers. Several researchers have studied the use of traditional herbal medicine in combination with docetaxel, to improve lung cancer treatment. SH003, a novel herbal mixture, exerts anticancer effects in different cancer cell types. Here, we aimed to investigate the apoptotic and anticancer effects of SH003 in combination with DTX, in human non-small-cell lung cancer (NSCLC). SH003, with DTX, induced apoptotic cell death, with increased expression of cleaved caspases and cleaved poly (ADP-ribose) polymerase in NSCLC cells. Moreover, SH003 and DTX induced the apoptosis of H460 cells via the suppression of the EGFR and signal transducer and activator of transcription 3 (STAT3) signaling pathways. In H460 tumor xenograft models, the administration of SH003 or docetaxel alone diminished tumor growth, and their combination effectively killed cancer cells, with increased expression of apoptotic markers and decreased expression of p-EGFR and p-STAT3. Collectively, the combination of SH003 and DTX may be a novel anticancer strategy to overcome the challenges that are associated with conventional lung cancer therapy.

ADGRF4 Regulates Non-small Cell Lung Cancer Cell Invasiveness.

BACKGROUND/AIM: Adhesion G protein-coupled receptors (aGPCRs) have a crucial role in cancer. However, the role of ADGRF4, one of aGPCRs, in cancer has yet to be revealed. Therefore, we investigated its role in lung cancer, a leading cause of cancer-related deaths worldwide. MATERIALS AND METHODS: ADGRF4 gene expression pattern in lung cancer were analyzed by in silico analyses. RNA sequencing was conducted to investigate gene expression pattern altered by ADGRF4 knockdown. Lung cancer cell lines were subjected to cell migration and invasion assays. RESULTS: In silico analysis data indicated a major role of ADGRF4 in lung cancer. RNA sequencing data showed that ADGRF4 gene silencing in lung cancer cells altered global expression pattern. ADGRF4 gene silencing reduced lung cancer cell invasiveness. Furthermore, PPP2C gene expression was most significantly down-regulated by ADGRF4 gene silencing. PPP2C overexpression rescued cell invasiveness inhibited by ADGRF4 gene silencing, and PPP2C gene silencing blocked lung cancer cell invasiveness. CONCLUSION: ADGRF4 regulates lung cancer cell invasiveness via PPP2C.

Regulation of a long noncoding RNA MALAT1 by aryl hydrocarbon receptor in pancreatic cancer cells and tissues.

Environmental toxicants such as dioxins and polycyclic aromatic carbons are risk factors for pancreatitis and pancreatic cancer. These toxicants activate aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, of which activation regulates many downstream biological events, including xenobiotic metabolism, inflammation, and cancer cell growth and transformation. Here, we identified that environmental toxicant-activated AHR increased expression of metastasis associated lung adenocarcinoma transcript 1 (MALAT1) in pancreatic cancer cells and pancreatic tissues. The MALAT1 is a long noncoding (lnc) RNA which interacts with Enhancer of Zeste 2 (EZH2), a histone methyltransferase with epigenetic silencer activity, and the MALAT1-EZH2 interaction increased its epigenetic silencing activity. In contrast, AHR antagonist, CH223191 or resveratrol, counteracted the AHR-mediated MALAT1 induction and MALAT1-enahnced EZH2 activity. Collectively, these results revealed a novel pathway of how environmental exposure leads to epigenetic alteration via activation of AHR-MALAT1-EZH2 signaling axis under pancreatic tissue- and cancer cell-context.

Ginseng Seed Oil Inhibits the Growth of Estrogen Receptor-positive Breast Cancer Cells.

BACKGROUND/AIM: Although ginseng seed oil (GSO) appears to have various roles in the body, its anti-cancer effect has not been investigated. Tamoxifen is widely used to treat estrogen receptor-positive (ER+) breast cancer but shows adverse effects with drug resistance. This study investigated the effect of GSO in ER+ breast cancer cell growth. MATERIALS AND METHODS: Cell viability assays, western blots and Annexin V staining were conducted to examine cell viability and apoptosis. The synergistic effect of tamoxifen in combination with GSO or oleic acid (OA) was determined. RESULTS: GSO and OA caused apoptosis of MCF-7 ER+ breast cancer cells and had synergistic effects with tamoxifen in inhibiting tamoxifen-resistant MCF-7 (MCF-7TAMR) ER+ breast cancer cell growth. CONCLUSION: GSO may block ER+ breast cancer recurrence in combination with tamoxifen.

Kisspeptin Promotes Glioblastoma Cell Invasiveness Via the Gq-PLC-PKC Pathway.

BACKGROUND/AIM: Kisspeptin produced from the KISS1 gene is secreted from the living cells, binds to endogenous receptor KISS1R (also called G protein-coupled receptor 54, GPR54), and has various functions in normal physiological conditions. Although an anti-metastatic role of kisspeptin in cancer is well known in several cancer types, its role in brain tumors is not yet understood. Herein, we investigated a the role of kisspeptin in glioblastoma cells. MATERIALS AND METHODS: Glioblastoma cells were treated with kisspeptin and subjected to proliferation, migration, and invasion assays. KISS1R dependency was tested by KISS1R silencing with KISS1R siRNAs. RESULTS: Kisspeptin inhibited migratory and invasive abilities of U87-MG, U-251-MG and U373-MG glioblastoma cells with no effect on cell viability. KISS1R gene silencing with KISS1R siRNAs blocked kisspeptin-induced glioblastoma cell invasiveness. Moreover, chemical inhibitors against Gq, PLC or PKC blocked kisspeptin-induced glioblastoma cell invasiveness. CONCLUSION: Kisspeptin induces glioblastoma cell invasiveness via the KISS1R-Gq-PLC-PKC signaling pathway.

Kisspeptin Inhibits Colorectal Cancer Cell Invasiveness by Activating PKR and PP2A.

BACKGROUND/AIM: The aim of the present study was to investigate the mechanism through which kisspeptin inhibits colorectal cancer metastasis. MATERIALS AND METHODS: Colorectal cancer cells were treated with kisspeptin and then subjected to assays for cell viability, migration, invasion and anchorage-independent growth. Kisspeptin receptor (KISS1R) requirement was examined by siRNA-based gene silencing followed by western blot and invasion assays. Kisspeptin regulation of PKR and PP2A was examined by treating cells with inhibitors for PKR or PP2A. RESULTS: Kisspeptin inhibited colorectal cancer cell invasiveness without affecting cell proliferation. Kisspeptin required activation of KISS1R and resulted in activation of PKR and PP2A. PKR inhibitor blocked kisspeptin-induced PP2A phosphorylation, while PP2A inhibitor failed to block kisspeptin-induced PKR phosphorylation. CONCLUSION: Kisspeptin-mediated activation of PKR-PP2A inhibited colorectal cancer cell invasiveness.

Novel herbal medicine LA16001 ameliorates cisplatin-induced anorexia.

Chemotherapy frequently causes anorexia in cancer patients, which has been associated with poor disease prognosis. Several therapeutic strategies for the treatment of chemotherapy­induced anorexia are available; however, their adverse effects limit their clinical use. Herbal medicines have a long history of use for the treatment of various diseases, including cancer, and recent research has demonstrated their safety and efficacy. In the present study, combinations of herbal medicines were designed based on traditional Korean medicine, and their effects were investigated on chemotherapy­induced anorexia. Herbal mixtures were extracted, composed of Atractylodes japonica, Angelica gigas, Astragalus membranaceus, Lonicera japonica Thunb., Taraxacum platycarpum H. Dahlstedt and Prunella vulgaris var. asiatica (Nakai) Hara. The mixtures were termed LCBP­Anocure­16001­3 (LA16001, LA16002, LA16003). A cisplatin­induced anorexic mouse model was used to evaluate the putative effects of the extracts on chemotherapy­induced anorexia. Treatment with LA16001 was revealed to prevent body weight loss, and all three extracts were demonstrated to improve food intake. When the molecular mechanisms underlying the orexigenic effects of LA16001 were investigated, altered expression levels of ghrelin, leptin and interleukin­6 were revealed. Furthermore, LA16001 was reported to induce phosphorylation of Janus kinase 1 and signal transducer and activator of transcription 3. In addition, LA16001 administration increased the number of white blood cells and neutrophils. These results suggested that the herbal formula LA16001 may be able to prevent chemotherapy­induced anorexia and may have potential as a novel therapeutic strategy for the adjuvant treatment of patients with cancer.

Herbal prescription, Danggui-Sayuk-Ga-Osuyu-Senggang-Tang, inhibits TNF-α-induced epithelial-mesenchymal transition in HCT116 colorectal cancer cells.

Tumor necrosis factor­α­mediated (TNF­α) epithelial­mesenchymal transition (EMT) is associated with distant metastasis in patients with colorectal cancer with poor prognosis. Although traditional herbal medicines have long been used to treat colorectal cancer, the incidence and mortality in patients with colorectal cancer has continued to increase. Danggui­Sayuk­Ga­Osuyu­Saenggang­Tang (DSGOST) has long been used for treatment of chills, while few studies have reported its anticancer effect. This study aimed to demonstrate the inhibitory effect of DSGOST on TNF­α­mediated invasion and migration of colorectal cancer HCT116 cell lines. MTT was used to measure cell viability. Wound healing and Τranswell invasion assay were used to detect migration and invasion of cells, respectively. The intracellular localization of proteins of interest was assessed by immunocytochemistry. Western blotting was performed to determine the expression level of various proteins. A non­toxic dose of DSGOST (50 µg/ml) on HCT116 cells was determined by MTT assay. Furthermore, DSGOST prevented the TNF­α­induced invasive phenotype in HCT116 cells. DSGOST inhibition of the invasive phenotype was also associated with increased expression of EMT markers. Furthermore, DSGOST treatment blocked TNF­α­induced migration and invasion of HCT116 cells. In addition, DSGOST treatment inhibited TNF­α­mediated nuclear translocation of Snail. DSGOST treatment also downregulated TNF­α­induced phosphorylation of AKT and glycogen synthase kinase­3ß. Therefore, the findings of the current study suggest that DSGOST exhibits anti­migration and anti­invasion effects in TNF­α­treated HCT116 human colorectal cells.

APC downregulated 1 inhibits breast cancer cell invasion by inhibiting the canonical WNT signaling pathway.

Canonical WNT signaling promotes breast cancer progression. Although APC downregulated 1 (APCDD1) may inhibit canonical WNT signaling, its role in breast cancer remains to be fully understood. The present study demonstrated that APCDD1 suppressed in vitro breast cancer growth and metastasis by inhibiting canonical WNT signaling. The present study demonstrated that APCDD1 expression was negatively associated with breast cancer cell invasion, which was consistent with previous studies that indicated that APCDD1 expression was decreased in invasive ductal carcinoma compared with that in ductal carcinoma in situ. Furthermore, APCDD1 expression was negatively associated with nuclear ß-catenin expression and transcription factor/lymphoid enhancer binding factor 1 transcriptional activity in the present study. Silencing APCDD1 in non-invasive breast cancer cells using lentiviral APCDD1 short hairpin RNAs enhanced migration and invasion, which may be mediated by canonical WNT signaling, whereas the overexpression of human influenza hemagglutinin-tagged APCDD1 in invasive breast cancer cells repressed these properties. Therefore, the present study suggested that APCDD1 regulated breast cancer progression by targeting canonical WNT signaling and modulating breast cancer cell invasion.

SH003 suppresses breast cancer growth by accumulating p62 in autolysosomes.

Drug markets revisits herbal medicines, as historical usages address their therapeutic efficacies with less adverse effects. Moreover, herbal medicines save both cost and time in development. SH003, a modified version of traditional herbal medicine extracted from Astragalus membranaceus (Am), Angelica gigas (Ag), and Trichosanthes Kirilowii Maximowicz (Tk) with 1:1:1 ratio (w/w) has been revealed to inhibit tumor growth and metastasis on highly metastatic breast cancer cells, both in vivo and in vitro with no toxicity. Meanwhile, autophagy is imperative for maintenance cellular homeostasis, thereby playing critical roles in cancer progression. Inhibition of autophagy by pharmacological agents induces apoptotic cell death in cancer cells, resulting in cancer treatment. In this study, we demonstrate that SH003-induced autophagy via inhibiting STAT3 and mTOR results in an induction of lysosomal p62/SQSTM1 accumulation-mediated reactive oxygen species (ROS) generation and attenuates tumor growth. SH003 induced autophagosome and autolysosome formation by inhibiting activation of STAT3- and mTOR-mediated signaling pathways. However, SH003 blocked autophagy-mediated p62/SQSTM1 degradation through reducing of lysosomal proteases, Cathepsins, resulting in accumulation of p62/SQSTM1 in the lysosome. The accumulation of p62/SQSTM1 caused the increase of ROS, which resulted in the induction of apoptotic cell death. Therefore, we conclude that SH003 suppresses breast cancer growth by inducing autophagy. In addition, SH003-induced p62/SQSTM1 could function as an important mediator for ROS generation-dependent cell death suggesting that SH003 may be useful for treating breast cancer.

Loss of NR2E3 represses AHR by LSD1 reprogramming, is associated with poor prognosis in liver cancer.

The aryl hydrocarbon receptor (AHR) plays crucial roles in inflammation, metabolic disorder, and cancer. However, the molecular mechanisms regulating AHR expression remain unknown. Here, we found that an orphan nuclear NR2E3 maintains AHR expression, and forms an active transcriptional complex with transcription factor Sp1 and coactivator GRIP1 in MCF-7 human breast and HepG2 liver cancer cell lines. NR2E3 loss promotes the recruitment of LSD1, a histone demethylase of histone 3 lysine 4 di-methylation (H3K4me2), to the AHR gene promoter region, resulting in repression of AHR expression. AHR expression and responsiveness along with H3K4me2 were significantly reduced in the livers of Nr2e3rd7 (Rd7) mice that express low NR2E3 relative to the livers of wild-type mice. SP2509, an LSD1 inhibitor, fully restored AHR expression and H3K4me2 levels in Rd7 mice. Lastly, we demonstrated that both AHR and NR2E3 are significantly associated with good clinical outcomes in liver cancer. Together, our results reveal a novel link between NR2E3, AHR, and liver cancer via LSD1-mediated H3K4me2 histone modification in liver cancer development.

Kisspeptin inhibits cancer growth and metastasis via activation of EIF2AK2.

Kisspeptin is a protein encoded by the KISS1 gene, which has been reported to suppress the metastatic capabilities of various types of cancer cells, through the activation of its G­protein coupled receptor GPR54. However, the molecular mechanisms underlying the involvement of kisspeptin­mediated signaling in the inhibition of cancer cell migration and invasion have yet to be elucidated. The present in vitro cell proliferation, migration and invasion assays and in vivo experimental metastasis studies demonstrated that kisspeptin­induced eukaryotic translation initiation factor 2α kinase 2 (EIF2AK2) activation suppressed the metastatic capabilities of several types of cancer cells. Kisspeptin was revealed to inhibit the migratory and invasive abilities of highly metastatic breast SK­BR­3, prostatic PC­3 and colorectal adenocarcinoma LoVo human cancer cell lines, whereas its inhibitory effects were abolished following the silencing of EIF2AK2 expression using RNA interference. Similarly, kisspeptin failed to inhibit the migration and invasion of mouse embryonic fibroblasts following the deletion of the EIF2AK2 gene. Furthermore, kisspeptin was demonstrated to activate Ras homolog gene family member A (RhoA)­dependent signaling, and to phosphorylate EIF2AK2 via RhoA­mediated pathways in various cancer cells. In addition, results obtained from nude mice bearing LoVo­derived xenograft tumors revealed that kisspeptin inhibited tumor growth through an EIF2AK2­dependent mechanism, and an in vivo metastasis assay identified kisspeptin­activated EIF2AK2 signaling as critical for the suppression of distant metastasis. The present study concluded that kisspeptin represses cancer metastasis via EIF2AK2 signaling, thus clarifying the role of kisspeptin signaling in complicated cancer metastasis signaling network. Therefore, kisspeptin treatment may be a choice for blocking metastases.

Melatonin-induced KiSS1 expression inhibits triple-negative breast cancer cell invasiveness.

Breast cancer is one of the most common types of cancer in women, and its metastasis increases the risk of mortality. Melatonin, a hormone that regulates the circadian rhythm, has been revealed to inhibit breast cancer growth and metastasis. However, its involvement in highly metastatic triple-negative breast cancer cells is yet to be elucidated. The present study demonstrated that melatonin inhibited the metastatic abilities of triple-negative breast cancer cells and prolonged its inhibitory effect via the expression of kisspeptin (KiSS1), which is a suppressor of metastasis. Melatonin at concentrations ranging from 1 nM to 10 µM did not affect the proliferation of metastatic MDA-MB-231 and HCC-70 triple-negative breast cancer cells. However, melatonin repressed invasiveness in triple-negative breast cancer cells. Additionally, conditional medium from melatonin-treated MDA-MB-231 cells repressed the invasiveness of triple-negative breast cancer cells. Melatonin promoted the production of KiSS1, a metastasis suppressor encoded by the KiSS1 gene. In addition, melatonin increased KiSS1 expression via the expression and transcriptional activation of GATA binding protein 3. Silencing of KiSS1 weakened melatonin inhibition of breast cancer cell invasiveness. Therefore, the present study concluded that melatonin activates KiSS1 production in metastatic breast cancer cells, suggesting that melatonin activation of KiSS1 production may regulate the process of breast cancer metastasis.

Barley grass extract causes apoptosis of cancer cells by increasing intracellular reactive oxygen species production.

Cancer remains a leading cause of mortality worldwide, therefore food products are being investigated for potential prevention or treatment strategies. The ingredient, barley grass extract (Hordeum vulgare L.; Bex) is used to prevent or ameliorate various types of disease. In cancer, Bex has been revealed to inhibit tumor growth. However, its effect on cancer cells is yet to be clearly defined. In the present study, the effect of Bex on cancer cell growth was investigated. Bex inhibited the viabilities of breast and prostate cancer cells according to the results of MTT assays. Accordingly, Bex caused apoptosis, which was confirmed by Annexin V staining and western blot analysis for poly (ADP-ribose) polymerase and caspases. Furthermore, Bex increased the intracellular levels of reactive oxygen species (ROS), and N-acetyl-L-cystein blocked Bex-induced apoptosis. Therefore, the study demonstrated that Bex causes apoptosis of breast and prostate cancer cells by increasing intracellular ROS levels.

Inhibitory effect of Angelica gigas on cold­induced RhoA activation in vascular cells.

The herbal extract Angelica gigas (AG) has been applied as a vasodilating agent for patients suffering from vascular diseases for many years; however, the underlying mechanism has not been fully elucidated. The present study hypothesized that the anti­vasoconstrictive effect of AG may be effective in the treatment of abnormal cold­mediated vasospasms that occur in Raynaud's phenomenon (RP). The effect of AG on the activity of ras homolog gene family member A (RhoA) was investigated in cold­exposed vascular cells. Vascular cells were pretreated to AG, followed by a warm (37˚C) or cold (25˚C) incubation for 30 min and investigated with western blotting, ELISA and confocal microscopy. Cold treatment induced the activation of RhoA in pericytes and vascular endothelial cells, however this was reduced by treatment with AG. Furthermore, AG treatment reduced the endothelin­1 (ET­1)­mediated RhoA activation in pericytes; however, cold­induced ET­1 production by vascular endothelial cells was not affected by treatment with AG. In addition, AG treatment suppressed the formation of stress fibers and focal adhesion complexes, and the cold­induced phosphorylation of focal adhesion kinase, proto­oncogene tyrosine­protein kinase Src and extracellular signal­related kinase. Therefore, AG treatment demonstrated an ability to reduce cold­induced RhoA activation in pericytes and vascular endothelial cells, and attenuated ET­1­mediated RhoA activation in pericytes. In conclusion, the present study indicated that AG may be useful for the treatment of RP.

SH003 enhances paclitaxel chemosensitivity in MCF-7/PAX breast cancer cells through inhibition of MDR1 activity.

Paclitaxel is an anti-cancer drug for treating cancer, but paclitaxel resistance is reported in cancer cells. Multidrug resistance (MDR) is related with the epithelial-to-mesenchymal transition (EMT) mechanism, which plays a key role in cancer metastasis. Moreover, EMT mechanism is connected to tamoxifen resistance in breast cancer cells. Consequently, oncologists are interested in finding new MDR1 inhibitors originating from herbal medicines to have less side-effect. Here, we investigated an inhibition effect of SH003 on MDR1 activity in paclitaxel-resistant MCF-7/PAX breast cancer cells. Our results showed that paclitaxel did not inhibit a proliferation in paclitaxel-resistant MCF-7 breast cancer cells. Paclitaxel-resistant MCF-7 cells showed an increase of MDR1 activity, which was confirmed by measuring an amount of accumulated rhodamine 123 in the cells. Also, qRT-PCR and Western blot assays confirmed that paclitaxel-resistant MCF-7 cells exhibited high MDR1 expression level. Furthermore, paclitaxel-resistant MCF-7 cells showed mesenchymal morphology with alterations of EMT markers, and acquired tamoxifen resistance with a decrease of ERα expression. We also found that a combinatorial treatment of SH003 and paclitaxel in paclitaxel-resistant MCF-7 cells caused apoptosis in synergistic manner, which was due to SH003 inhibition of MDR1 expression. Therefore, SH003 could be a potential agent for overcoming MDR in drug-resistant cancer cells.

SH003 induces apoptosis of DU145 prostate cancer cells by inhibiting ERK-involved pathway.

BACKGROUND: Herbal medicines have been used in cancer treatment, with many exhibiting favorable side effect and toxicity profiles compared with conventional chemotherapeutic agents. SH003 is a novel extract from Astragalus membranaceus, Angelica gigas, and Trichosanthes Kirilowii Maximowicz combined at a 1:1:1 ratio that impairs the growth of breast cancer cells. This study investigates anti-cancer effects of SH003 in prostate cancer cells. METHODS: SH003 extract in 30% ethanol was used to treat the prostate cancer cell lines DU145, LNCaP, and PC-3. Cell viability was determined by MTT and BrdU incorporation assays. Next, apoptotic cell death was determined by Annexin V and 7-AAD double staining methods. Western blotting was conducted to measure protein expression levels of components of cell death and signaling pathways. Intracellular reactive oxygen species (ROS) levels were measured using H2DCF-DA. Plasmid-mediated ERK2 overexpression in DU145 cells was used to examine the effect of rescuing ERK2 function. Results were analyzed using the Student's t-test and P-values < 0.05 were considered to indicate statistically-significant differences. RESULTS: Our data demonstrate that SH003 induced apoptosis in DU145 prostate cancer cells by inhibiting ERK signaling. SH003 induced apoptosis of prostate cancer cells in dose-dependent manner, which was independent of androgen dependency. SH003 also increased intracellular ROS levels but this is not associated with its pro-apoptotic effects. SH003 inhibited phosphorylation of Ras/Raf1/MEK/ERK/p90RSK in androgen-independent DU145 cells, but not androgen-dependent LNCaP and PC-3 cells. Moreover, ERK2 overexpression rescued SH003-induced apoptosis in DU145 cells. CONCLUSIONS: SH003 induces apoptotic cell death of DU145 prostate cancer cells by inhibiting ERK2-mediated signaling.

Decursin in Angelica gigas Nakai (AGN) Enhances Doxorubicin Chemosensitivity in NCI/ADR-RES Ovarian Cancer Cells via Inhibition of P-glycoprotein Expression.

Angelica gigas Nakai (AGN, Korean Dang-gui) is traditionally used for the treatment of various diseases including cancer. Here, we investigated multidrug-resistant phenotype-reversal activities of AGN and its compounds (decursin, ferulic acid, and nodakenin) in doxorubicin-resistant NCI/ADR-RES ovarian cancer cells. Our results showed that a combination of doxorubicin with either AGN or decursin inhibited a proliferation of NCI/ADR-RES cells. These combinations increased the number of cells at sub-G1 phase when cells were stained with Annexin V-fluorescein isothiocyanate. We also found that these combinations activated caspase-9, caspase-8, and caspase-3 and increased cleaved PARP level. Moreover, an inhibition of P-glycoprotein expression by either AGN or decursin resulted in a reduction of its activity in NCI/ADR-RES cells. Therefore, our data demonstrate that decursin in AGN inhibits doxorubicin-resistant ovarian cancer cell proliferation and induces apoptosis in the presence of doxorubicin via blocking P-glycoprotein expression. Therefore, AGN would be a potentially novel treatment option for multidrug-resistant tumors by sensitizing to anticancer agents. Copyright © 2016 John Wiley & Sons, Ltd.