Jaeumganghwa-Tang Induces Apoptosis via the Mitochondrial Pathway and Lactobacillus Fermentation Enhances Its Anti-Cancer Activity in HT1080 Human Fibrosarcoma Cells.

Jaeumganghwa-tang (JGT, Zi-yin-jiang-huo-tang in Chinese and Jiin-koka-to in Japanese) is an oriental herbal formula that has long been used as a traditional medicine to treat respiratory and kidney diseases. Recent studies revealed that JGT exhibited potent inhibitory effects on allergies, inflammation, pain, convulsions, and prostate hyperplasia. Several constituent herbs in JGT induce apoptotic cancer cell death. However, the anti-cancer activity of JGT has not been examined. In this study, we investigated the anti-cancer effects of JGT using highly tumorigenic HT1080 human fibrosarcoma cells and elucidated the underlying mechanisms. In addition, we examined whether the Lactobacillus fermentation of JGT enhanced its anti-cancer activity using an in vivo xenograft model because fermentation of herbal extracts is thought to strengthen their therapeutic effects. Data revealed that JGT suppressed the growth of cancer cells efficiently by stimulating G1 cell cycle arrest and then inducing apoptotic cell death by causing mitochondrial damage and activating caspases. The phosphorylation of p38 and ERK also played a role in JGT-induced cell death. In vitro experiments demonstrated that JGT fermented with Lactobacillus acidophilus, designated fJGT162, elicited similar patterns of cell death as did non-fermented JGT. Meanwhile, the daily oral administration of 120 mg/kg fJGT162 to HT1080-bearing BALB/c nude mice suppressed tumor growth dramatically (up to 90%) compared with saline treatment, whereas the administration of non-fermented JGT suppressed tumor growth by ~70%. Collectively, these results suggest that JGT and fJGT162 are safe and useful complementary and alternative anti-cancer herbal therapies, and that Lactobacillus fermentation improves the in vivo anti-cancer efficacy of JGT significantly.

Introduction

In recent years, traditional Chinese medicine (TCM) has gained increasing attention as a resource for drug discovery. Because TCM-based herbal extracts are generally low in cost and exhibit little toxicity or side effects in clinical practice, they have been applied as alternative medicines to treat a wide range of human diseases, including cancer, in China, Japan, Korea, and other Asian countries [1-4]. In TCM, herbs are used in combination as formulas, which are believed to enhance their therapeutic efficacy and reduce adverse effects simultaneously. For example, Ka-mi-kae-kyuk-tang (KMKKT), a formula of 10 oriental herbs, has anti-angiogenic, anti-metastatic, and anti-cancer activities in vivo with no obvious side effects [5]. Furthermore, KMKKT stimulates bone marrow stem cell hematopoiesis and alleviates anti-cancer drug-induced leukopenia side effects in mice [6,7]. In addition, Bojungbangdocktang (BJBDT), which has been used for the prevention or treatment of cancers in Korea, functions by blocking VEGF/VEGFR activity to inhibit angiogenesis in human umbilical vein endothelial cells (HUVECs) [8]. It also prevents cisplatin-induced toxicity and apoptosis in MCF-10A normal human breast epithelial cells, but not in breast cancer cells [9]. These results strongly suggest that herbal medicines have potentially beneficial effects on cancer progression and ameliorate conventional chemotherapy- or radiotherapy-induced complications.

The fermentation of medicinal herbs, a decomposition process mediated by microbes or fungus, is thought to exert favorable effects on the absorption, bioavailability, and pharmacological activity of herbal extracts by accelerating the production or conversion of active components into their metabolites or by creating low molecular weight substances such as aglycone from glycoside [10,11]. In addition, several studies have demonstrated that the fermentation of medicinal herbal extracts improves their therapeutic effects. For example, the fermentation of Anoectochilus formosanus using Lactobacillus acidophilus improved its anti-oxidant activity by increasing the amount of total phenol [12]. Recently, our group reported beneficial effects of Lactobacillus fermentation, wherein hwangryunhaedoktang (HR) and oyaksungisan (OY) exhibited enhanced anti-inflammatory effects in LPS-stimulated RAW 264.7 cells after fermentation [13,14]. In addition, the administration of fermented HR had a greater inhibitory effect on bone loss in ovariectomized (OVA) rats by enhancing bone mineral density and bone microstructure compared with non-fermented HR [15].

Jaeumgangwha-tang (JGT, Zi-yin-jiang-huo-tang in Chinese, Jiin-koka-to in Japanese) is an oriental traditional herbal formula, and has long been used in China, Japan, and Korea to nourish yin and direct fire downward caused by the lack of kidney water. JGT has been described in the Dongui Bogam, a Korean book complied by Heo Jun (1539–1615), to have pharmacological effects for the treatment of respiratory and renal diseases, night sweats, coughing, fever in the afternoon, profuse phlegm, hemoptysis, loss of appetite, spitting blood, constipation, and facial flushing. Recent studies demonstrated that JGT inhibited allergic reactions, inflammation, pain, and convulsions, and potentiated the immune response [16]. In addition, JGT inhibited the development of testosterone propionate (TP)-induced benign prostate hyperplasia (BPH) dramatically in a rat model [17]. JGT consists of 12 medicinal herbs, including Paeoniae Radix, Angelicae Gigantis Radix, Rehmanniae Radix Preparata, Atractylodis Rhizoma Alba, Liriopis Tuber, Rehmanniae Radix Crudus, Citri Unshius Pericarpium, Anemarrhenae Rhizoma, Phellodendri Cortex, Glycyrrhizae Radix et Rhizoma, Zingiberis Rhizoma Crudus, and Zizyphi Fructus. Several single herbs in JGT, including Angelicae Gigantis Radix, Asparagi Tuber, Anemarrhenae Rhizoma, and Paeoniae Radix, elicit anti-cancer effects by inducing apoptosis [18]. However, no studies have yet reported anti-cancer effects of JGT.

In this study, we examined the anti-cancer effect of JGT in terms of inducing cell death and inhibiting tumor growth in vivo using highly tumorigenic HT1080 human fibrosarcoma cells and elucidated the detailed mechanism of action behind its chemotherapeutic activity. Furthermore, we investigated whether Lactobacillus fermentation improved the anti-cancer effects of JGT using an in vivo tumor xenograft model.

Materials and Methods

Cell lines

Human fibrosarcoma HT1080 cells (KCLB no. 10121), human prostate adenocarcinoma PC-3 cells (KCLB no. 21435), and human gastric carcinoma AGS cells (KCLB no. 21739) were obtained from the Korean Cell Line Bank (Seoul, Korea) and cultured in RPMI 1640 (Cellgro, Manassas, VA, USA) supplemented with 10% (v/v) heat-inactivated fetal bovine serum (Cellgro) and penicillin (100 U/mL)/streptomycin (100 μg/mL) (Cellgro) at 37°C in a humidified 5% CO2 incubator. Murine hepatocytes were isolated using a perfusion system with some modification and incubated as described previously [19].

Animals

Five-week-old female BALB/c nude mice were purchased from Nara Biotech (Seoul, Korea) and housed under specific pathogen-free facility under constant conditions (12 h light-dark cycle at 22 ± 1°C and 55 ± 5% humidity). All animal experiments were approved by the Animal Care and Use Committee of the Korea Institute of Oriental Medicine (KIOM, Daejeon, Korea) with reference number #14–040 and performed according to the guidelines of the Animal Care and Use Committee at KIOM.

Chemicals and antibodies

Rhodamine 123, propidium iodide (PI), 4',6-Diamidino-2-phenylindole (DAPI), and 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) were purchased from Sigma Chemical Co. (St. Louis, MO, USA). SP600125, SB203580, and PD98059 were obtained from Calbiochem (San Diego, CA). Antibodies against p21, p27, cyclin B, cyclin D, cyclin E, cyclin-dependent kinase (CDK)2, CDK4, CDK6, Bcl-2, XIAP, Bad, p-Bad, Bax, Bim, Bok, caspase-3, cleaved caspase-7, caspase-8, caspase-9, poly ADP ribose polymerase (PARP), p38, p-p38 (Thr180/Tyr182), extracellular regulated kinase (ERK)1/2, p-ERK1/2 (Thr202/Tyr204), c-Jun N-terminal kinase (JNK), and p-JNK (Thr183/Tyr185) were purchased from Cell Signaling Technology (Danvers, MA, USA). Anti-α-tubulin was obtained from Santa Cruz Biotechnology Inc. (Santa Cruz, CA, USA). For high-performance liquid chromatography (HPLC), acetonitrile of HPLC-grade was obtained from J. T. Bakers (Philipsburg, NJ, USA) and trifluroacetic acid (TFA) and 5-hydroxymethyl furfural (5-HMF) were obtained from Sigma. Paeoniflorin and glycyrrhizin were purchased from Tokyo Chemical Industry Co. (Tokyo, Japan). Nodakenin, nodakenetin, berberine, and palmatine were obtained from Faces Biochemical Co. (Wuhan, China), and hesperidin was obtained from Korea Food and Drug Administration (KFDA, Osong, Korea).

Preparation of JGT, aJGT, and fJGT162

Herbs for a decoction of JGT were purchased from Yeongcheon Oriental Herbal Market (Yeongcheon, Korea) and the amount of each herb was listed in Table 1. The authenticity of the plant species was validated by Prof. Ki Hwan Bae (Chungnam National University, Daejeon, Korea), and all voucher specimens were deposited in the herbal bank in KIOM. A total of 1874.5 g chopped JGT formula was soaked in 18.745 L distilled water, boiled for 3 h using Herb Extractor (Cosmos-600 Extractor, Gyungseo Co., Korea), and then filtered through standard testing sieves (150 μm, Retsch, Haan, Germany). Prior to fermentation, decoction JGT was adjusted to pH 7.0 using 1 M NaOH and then sterilized by autoclaving for 15 min at 121°C. A pure culture of Lactobacillus acidophilus (KFRI162) was obtained from Korea Food Research Institute (KFRI) and incubated in MRS medium for 24 h at 37°C as described previously [20]. To prepare fJGT162, autoclaved JGT (aJGT) was added with 1 × 108 CFU/mL L. acidophilus, and fermented at 37°C for 48 h. The final pH of wild-type JGT, aJGT, and fJGT162 was 7.00 ± 0.00, 5.45 ± 0.01, and 3.80 ± 0.01, respectively. JGT, aJGT, and fJGT162 were passed through a 60-μm nylon net filter (Millipore, Bedford, MA, USA), freeze-dried, and stored in a desiccator at 4°C. For in vitro experiments, the freeze-dried powder was dissolved in 10% (v/v) DMSO in distilled water (DW) to a final concentration of 50 mg/mL and centrifuged at 14,000 rpm for 10 min; the supernatant was then filtered (0.22 μm, pore size).

Table 1

Crude composition of JGT.

Herbal name	Scientific name	Amount (g)	Location of origin
Paeoniae Radix	Paeonia pactiflora	5.2	Yeongcheon, Korea
Angelicae Gigantis Radix	Angelica gigas	4.8	Pyeongchang, Korea
Rehmanniae Radix Preparata	Rehmannia glutinosa	4.0	Gunwi, Korea
Atractylodis Rhizoma Alba	Atractylodes japonica	4.0	Yeongcheon, Korea
Liriopis Tuber	Liriope platyphylla	4.0	Miryang, Korea
Rehmanniae Radix Crudus	Rehmannia glutinosa	3.2	China
Citri Unshius Pericarpium	Citrus unshiu	2.8	Jeju, Korea
Anemarrhenae Rhizoma	Anemarrhena asphodeloides	2.0	China
Phellodendri Cortex	Phellodendron amurense	2.0	China
Glycyrrhizae Radix et Rhizoma	Glycyrrhiza uralensis	2.0	China
Zingiberis Rhizoma Crudus	Zingiber officinale	1.49	Yeongcheon, Korea
Zizyphi Fructus	Zizyphus jujube	2.0	Yeongcheon, Korea
Total amount		37.49

Cell proliferation assay and DAPI staining

The cells plated in 96-well culture plates (5 × 103/well) were treated with the indicated concentrations for 48 h, and the MTT assays were performed as described previously [21]. For DAPI staining, cells grown and treated with JGT in 35-mm glass bottom dishes were fixed with 4% paraformaldehyde for 10 min, permeabilized with 0.1% Triton X-100 for 10 min, stained with DAPI (0.5 μg/mL) for 10 min, and observed under a confocal laser scanning microscope (FV10i-W; Olympus Optical Co. Ltd, Tokyo, Japan).

Cell cycle analysis

Cells in the exponential growth phase were treated with 1000 μg/mL JGT for 12, 24, and 48 h. After harvest, cells were washed twice with ice-cold PBS and fixed in ice-cold 70% ethanol at −20°C for at least 24 h. The fixed cells were washed twice with ice-cold PBS, and intracellular DNA was stained using PI solution (0.1% Triton X-100, 0.1 mM EDTA, 50 μg/mL RNase A, 50 μg/mL PI in PBS) at 4°C for 30 min in the dark. The cell cycle distribution was analyzed using FACSCalibur flow cytometry (BD Biosciences, San Jose, CA, USA) and WinMDI 2.8 software (J. Trotter, Scripps Research Institute, La Jolla, CA, USA).

Measuring mitochondrial membrane potential (MMP, ΔΨm)

After treatment with JGT (500 and 1000 μg/mL) for 24 and 48 h, cells were washed twice with PBS and then incubated with rhodamine 123 fluorescence dye at a final concentration of 5 μM at 37°C for 30 min. The fluorescence of rhodamine 123 was analyzed using a FACSCalibur flow cytometer and observed under a fluorescence microscope (Olympus TH4-200; Olympus Optical Co. Ltd). For JC-1 staining, cells grown and treated with JGT in 35-mm glass bottom dishes were stained with JC-1 (5 μg/mL) in the dark for 10 min at 37°C, washed with culture media, and observed under a confocal laser scanning microscope.

Western blot analysis

Cells were washed twice with PBS and whole cell lysates were obtained using the M-PER Mammalian Protein Extraction Reagent (Thermo Scientific, Rockford, IL, USA). Protein concentrations were determined using the bicinchoninic acid kit (Sigma). An equal amount of protein was electrophoresed, immunoblotted, and detected as reported previously [21].

In vivo tumor xenograft model

Female BALB/c nude mice at 6-week-age (n = 15) were injected subcutaneously into the abdominal region with HT1080 cells (2 × 106 /mouse). On day 7 after tumor inoculation when tumors reached to a volume of ~100 mm3, the mice were randomly divided into three groups (n = 5 per group), and daily administered with saline (control), aJGT (120 mg/kg), or fJGT162 (120 mg/kg) in a volume of 100 μL for 14 days. The administered dose for mice was calculated from the amount used in human adults (37.49 g/60 kg of body weight/day) and the yield of powdered extract (39.74% in aJGT and 39.53% in fJGT162). The mice were observed for the gross appearance and behavior, and their body weights were measured daily. On day 21, mice were euthanized by intraperitoneal injection of a mixture of Zoletil (Virbac, Magny-en-Vexin, France) and Rompun (Bayer, Seoul, Korea) (2:1, 200 μl), and then tumors were excised for measurement of their weight.

Safety assessment of aJGT and fJGT162

To evaluate the safety of aJGT and fJGT162, 6-week-old female BALB/c nude mice (n = 3 per group) were fed vehicle (saline), aJGT (120 mg/kg), or fJGT162 (120 mg/kg) daily during 14-day experimental period. Gross appearance and behavior of mice were daily checked and their body weights were measured every other day. On day 14, mice were sacrificed, and weights of major organs were measured. Collected whole blood and serum samples were analyzed for hematological and serological parameters using ADVIA 2120i hematology system (Siemens Healthcare Diagnostics, Tarrytown, NY) and XL 200 (Erba Diagnostics Mannheim, Germany), respectively.

Chromatographic analysis of JGT, aJGT, and fJGT162

To compare the phytochemical profiles of JGT, aJGT, and fJGT162, HPLC was performed using an HPLC-DAD machine (Lachrom Elite, Hitach High-Technologies Co., Tokyo, Japan) as described previously with some modifications [22]. Chromatographic separation was achieved using a Phenomenex Luca C18 column (4.6 mm × 250 mm, 5 μm). A gradient elution using 0.1% TFA in deionized water (A) and acetonitrile (B) was performed as follows: 0‒5 min with 5% B, 5‒15 min with 5‒12% B, 15‒25 min with 12% B, 25‒65 min with 12‒50% B, and 65‒70 min with 50‒50% B. The flow rate and injection volume were 1 mL/min and 10 μL, respectively, and HPLC chromatograms were obtained using UV at 190–400 nm. Standard (5‒125 μg/mL) and sample solutions (20 mg/mL) were dissolved and diluted in methanol.

Statistical analysis

Data are presented as means ± standard deviation (SD). Differences between groups were analyzed using Student’s t-test with the SigmaPlot 8.0 software (SPSS, Inc., Chicago, IL, USA). A p-value < 0.05 was considered to indicate a significant difference.

Results

JGT decreases viability and induces G1 cell cycle arrest in HT1080 cells

To examine the anti-cancer effect of JGT and elucidate the detailed mechanisms of its chemotherapeutic activity, we used highly tumorigenic HT1080 human fibrosarcoma cell line. We first examined the effects of JGT on cell growth using MTT assays after treatment with 25–1000 μg/mL JGT for 48 h. As shown in Fig 1A, treatment with 500 and 1000 μg/mL JGT decreased HT1080 cell viability markedly and induced most cells to shrink and round up, which is a typical feature of apoptosis. In addition, JGT reduced the viability of human gastric carcinoma AGS and human prostate carcinoma PC-3 cells in a dose-dependent manner, whereas a comparable concentration of DMSO up to 0.2% had little influence on cell proliferation (S1 Fig). In contrast, normal hepatocytes were not affected by JGT treatment, even after 48 h with 1000 μg/mL, in terms of cell proliferation or morphological appearance, suggesting that JGT is not hepatotoxic (Fig 1B). Analysis of cell cycle progression using PI staining showed that JGT treatment for 12 and 24 h increased the proportion of cells in G1 phase to 38.49 and 44.71%, respectively, compared with untreated control cells (33.22%). The number of apoptotic cells in the subG0/G1 phase was considerably increased by JGT to 4.99 and 9.49% after treatment for 24 and 48 h, respectively, compared with untreated control cells (1.13%), suggesting that JGT-mediated G1 cell cycle arrest retarded cell proliferation and consequently induced cell death (Fig 2A) as incubation period was prolonged. Consistent with this, Western blotting demonstrated that JGT increased the levels of the CDK inhibitors p21 and p27 and decreased levels of cyclin B, cyclin D, cyclin E, CDK2, CDK4, and CDK6 in HT1080 cells significantly compared with untreated control cells (Fig 2B).

Fig 1

The effects of JGT on cell viability and apoptotic morphological changes.

Human fibrosarcoma HT1080 cells (A) and murine hepatocytes (B) were treated with the indicated doses of JGT for 48 h, and cell viability was determined using MTT assays. JGT-treated cells were observed under an inverted microscope (40× magnification). Data are representative of three independent experiments performed in triplicate and are expressed as means ± SD. * p < 0.05 vs. untreated control.

Fig 2

JGT induces cell cycle arrest in the G1 phase.

(A) HT1080 cells were incubated with 1000 μg/mL JGT for 12, 24, and 48 h, and cell cycle distribution was analyzed after PI staining. (B) The levels of cell cycle-related proteins in JGT-treated cells were determined by Western blotting. The band intensities relative to those of untreated cells were calculated using ImageJ software after normalization to tubulin expression. Data are representative of three independent experiments.

JGT causes caspase-dependent apoptotic cell death in HT1080 cells by inducing mitochondrial damage

To clarify the apoptotic cell death caused by JGT, we first assessed levels of apoptosis-related proteins using Western blotting. As shown in Fig 3A, JGT reduced the expression of the anti-apoptotic proteins Bcl-2 and XIAP significantly, increased the levels of pro-apoptotic Bad, Bax, Bim, and Bok, and induced cleavage of caspase-3, -7, -8, -9, and PARP. Similar to observations in HT1080 cells, JGT regulated cell cycle-related, anti-apoptotic, and pro-apoptotic proteins and increased PARP cleavage in PC-3 cells (S2 Fig). DAPI staining confirmed that JGT increased the number of apoptotic nuclei showing chromatin condensation and DNA fragmentation (Fig 3B). In the intrinsic apoptosis pathway, disruption of mitochondrial membrane potential (MMP, m) is an irreversible point in the death cascade, and is governed by pro- and anti-apoptotic members of the Bcl-2 family. Specifically, pro-apoptotic Bax favors the leakage of apoptotic factors from the mitochondria, whereas anti-apoptotic Bcl-2 inhibits this leakage [23-25]. Measuring MMP (ΔΨm) using rhodamine 123 fluorescence dye revealed that JGT treatment induced the loss of MMP (ΔΨm) significantly in dose- and time-dependent manners. Treatment with 500 and 1000 μg/mL JGT for 48 h decreased the percentage of cells with a high MMP (ΔΨm) to 82.15% and 58.20%, respectively, compared with untreated control cells (94.38%) (Fig 4A). Fluorescence microscopy confirmed this decrease in MMP (ΔΨm; Fig 4B). In addition, the loss of MMP (ΔΨm) induced by JGT was confirmed using the fluorescent dye JC-1, which exhibits a potential-dependent accumulation in mitochondria. At a high MMP (ΔΨm), JC-1 remains in an aggregated form and is observed as red punctuate staining, whereas it appears as green diffuse monomeric staining at a low MMP. As shown in Fig 4C, JGT induced a remarkable dose-dependent loss of MMP (ΔΨm) 48 h post-treatment.

Fig 3

JGT induces apoptotic cell death.

(A) HT1080 cells were treated with 500 and 1000 μg/mL JGT for 24 and 48 h, and the levels of cell death-related proteins were examined by Western blotting. The band intensities relative to untreated cells were calculated using ImageJ software after normalization to tubulin expression. (B) For the detection of apoptotic nuclei, cells treated with 500 and 1000 μg/mL JGT for 48 h were stained with DAPI and observed under a confocal microscope. Data are representative of three independent experiments, and expressed as means ± SD of 5 random fields per sample. * p < 0.05 vs. untreated control.

Fig 4

JGT treatment reduces MMP (ΔΨm).

(A) Depolarization of the mitochondrial membrane potential (MMP, ΔΨ) was examined in control and JGT-treated HT1080 cells after staining with rhodamine 123. The percentage of cells with a high MMP (ΔΨ) compared with untreated control cells was calculated using WinMDI 2.8. (B) Rhodamine 123-stained cells were observed under a fluorescence microscope (40× and 200× magnification). (C) The loss of MMP (ΔΨ) was examined using JC-1 staining after treatment with JGT for 48 h (200× and 600× magnification). Data are representative of three independent experiments.

JGT induces cell death by activating p38 and ERK

Previous studies demonstrated that MAPK signaling pathways could induce either cell proliferation or cell death depending on the cell type and the stimulus [26,27]. Treatment with 1000 μg/mL JGT elevated the levels of phosphorylated p38 and ERK significantly, but had little influence on JNK phosphorylation in HT1080 cells (Fig 5A) and PC-3 cells (S3 Fig). To elucidate the role of p38 and ERK activation in JGT-mediated cell death, pharmacological inhibitors of p38 (SB203580), ERK (PD98059), and JNK (SP600125) were used. Pre-incubation with SB203580 and PD98059 protected JGT-treated cells from death efficiently, whereas SP600125 had little effect. Moreover, pre-incubation with the pan-caspase inhibitor z-VAD-FMK inhibited JGT-mediated cell death almost completely (Fig 5B and 5C). Collectively, these data suggest that JGT-mediated cell death is exerted via p38 and ERK activation followed by caspase activation.

Fig 5

JGT induces cell death by activating p38 and ERK.

(A) Cells were treated with 1000 μg/mL JGT for 1, 6, 12, and 24 h, and the levels of total and phosphorylated MAPKs were measured by Western blotting. The band intensities relative to untreated cells were calculated after normalization to tubulin expression. Data are representative of three independent experiments. (B) After pre-treatment with or without specific inhibitors (10 μM), cells were treated with 500 and 1000 μg/mL JGT for 48 h, and observed under an inverted microscope. (C) The viability of cells in (B) was determined using MTT assays. Data are representative of three independent experiments performed in triplicate and are expressed as means ± SD. * p < 0.05 vs. untreated control, # p < 0.05 vs. no inhibitor.

Fermentation of JGT improves its inhibitory effect on in vitro cell proliferation and in vivo tumor growth with no adverse effects

To investigate the effect of bacterial fermentation of JGT, we compared the anti-proliferative and cell death-inducing effects of wild-type JGT, autoclaved/non-fermented JGT (aJGT), and autoclaved/fermented JGT (fJGT162) in HT1080 cells. As shown in Fig 6A, aJGT and fJGT162 reduced the number of viable cells in a dose-dependent manner, similar to the effects observed with JGT in Fig 1A. However, fJGT162 exhibited a greater inhibitory effect on cell proliferation than did the non-fermented JGT and aJGT, and the apoptotic morphological changes in fJGT162-treated cells were more severe than those in aJGT-treated cells. In PC-3 cells and AGS cells, fJGT162 had improved activity on the inhibition of cell proliferation and induction of cell death compared to JGT and aJGT (S4 Fig). In addition, Western blotting revealed that both aJGT and fJGT162 increased the levels of p21, p27, Bax, and PARP cleavage, and decreased the levels of cyclin B, cyclin D, cyclin E, CDK2, CDK4, CDK6, and XIAP significantly compared with untreated control cells (Fig 6B). Moreover, both aJGT and fJGT162 activated p38 and ERK significantly but had little effect on JNK activation (Fig 6C), consistent with the effects of JGT treatment. To assess whether the anti-cancer effects of JGT were enhanced by fermentation, the in vivo tumor growth inhibitory effects of aJGT- and fJGT162 were compared. HT1080 cells were subcutaneously inoculated into the abdominal region of BALB/c nude mice, and 7 days later, the mice (n = 5) with sizable tumor (~100 mm3) were daily treated with saline, aJGT, or fJGT162 for 14 days. As shown in Fig 7A, treatment with 120 mg/kg aJGT suppressed tumor growth successfully compared with saline-treated control mice, whereas fJGT162 exhibited a more potent inhibitory effect on in vivo tumor growth than did aJGT. Control mice had a mean tumor weight of 3.95 ± 0.50 g, whereas mice treated with aJGT and fJGT162 had tumor weights of 1.26 ± 0.56 g and 0.54 ± 0.38 g, reflecting decreases of 68.1% and 86.3%, respectively (Fig 7B). These results suggest that JGT is a potent anti-cancer formulation, and that fermentation improves the in vivo anti-cancer effects of JGT remarkably. In addition, significant weight loss in aJGT- and fJGT162-administered mice was not observed throughout the treatment, indicating aJGT and fJGT162 did not elicit severe toxic effects (Fig 7C). To evaluate whether daily administration of aJGT and fJGT162 causes serious toxicity, we compared body weight, organ weight, and hematological/serological parameters in mice treated with vehicle (saline), aJGT, or fJGT162. The administration of aJGT and fJGT162 at a dose of 120 mg/kg for 14 days did not affect body and organ weights (S1 and S2 Tables). In addition, the values of GOT, GPT, BUN, CRE, and hematological parameters were not significantly different between aJGT-, fJGT162-, and saline-treated mice (S3 and S4 Tables). These data indicate that repeated administration of aJGT and fJGT162 at dose of 120 mg/kg have no adverse effects.

Fig 6

aJGT and fJGT162 induce cell death and activate p38/ERK.

(A) HT1080 cells were treated with the indicated concentrations of aJGT or fJGT162 for 48 h, and cell viability was evaluated using MTT assays and cell morphology was observed under an inverted microscope. Data are representative of three independent experiments performed in triplicate and are expressed as means ± SD. * p < 0.05 vs. untreated control, # p < 0.05 vs. JGT or aJGT. (B) The levels of cell cycle- and cell death-related proteins in aJGT- or fJGT162-treated HT1080 cells were examined by Western blotting 48 h post-treatment. (C) The activation of MAPKs was analyzed by Western blotting after aJGT or fJGT162 treatment for 1, 6, and 18 h. The band intensities relative to those of untreated cells were calculated after normalization to tubulin expression.

Fig 7

aJGT and fJGT162 suppress in vivo tumor growth in a xenograft model.

(A) HT1080 cells (2 × 106 /mouse in 200 μL PBS) were inoculated subcutaneously in BALB/c nude mice. After 7 days the mice were treated daily with saline (control), 120 mg/kg aJGT, or 120 mg/kg fJGT162 for 14 days. On day 21 after tumor inoculation, the tumors were removed and photographed. (B) The final tumor weight at the end of experiment was measured. (C) Body weight was measured during the experiment. Data are means ± SD.

Identifying the main components in JGT, aJGT, and fJGT162 using HPLC-DAD

To analyze active ingredients in JGT, aJGT, and fJGT162, we selected 8 marker compounds: 5-HMF (Rehmanniae Radix Preparata), paeoniflorin (Paeoniae Radix), glycyrrhizin (Glycyrrhizae Radix et Rhizoma), nodakenin and nodakenetin (Angelicae Gigantis Radix), berberine and palmatine (Phellodendri Cortex), and hesperidin (Citri Unshius Pericarpium). A gradient elution of water and acetonitrile was applied to acquire optimal separation, and TFA was used to enhance the peak shape and inhibit peak tailing. The UV wavelengths of the eight compounds were adjusted based on the maximum UV absorption of each component. Each compound in the samples was identified by comparing the retention times (t ) and UV spectra of chemically defined standard compounds. As shown in Fig 8 and S5 Fig, 5-HMF (1, t : 9.3 min), paeoniflorin (2, t : 32.6 min), nodakenin (3, t : 40.7 min), hesperidin (4, t : 43.3 min), nodakenetin (5, t : 48.2 min), berberine (6, t : 51.2 min), palmatine (7, t : 51.7 min), and glycyrrhizin (8, t : 61.1 min) were all present in JGT, aJGT, and fJGT162.

Fig 8

Chromatograms of eight major standard compounds in JGT, aJGT, and fJGT162, as analyzed using 3D-HPLC.

Three-dimensional chromatograms of a standard mixture of eight compounds in (A), JGT (B), aJGT (C), and fJGT162 (D) at 190‒400 nm (UV). 5-HMF (1), paeoniflorin (2), glycyrrhizin (3), nodakenin (4), nodakenetin (5), berberine (6), palmatine (7), and hesperidin (8) were identified.

Discussion

Cancer has emerged as a serious public health problem, because its incidence and mortality rate are increasing progressively. Most cancer patients are treated primarily using major conventional cancer therapies including surgery, chemotherapy, and radiotherapy. Although these therapies are effective against cancer, they also have serious complications such as fatigue, nausea, diarrhea, and hair loss. Therefore, it is necessary to find more effective therapies that enhance the anti-cancer efficacy and diminish the side effects caused by conventional chemotherapy and radiotherapy. TCM and herbal medicines have long been used for cancer management in China, Japan, and other Asian countries, and are increasingly accepted as complementary and alternative medicines (CAM) in Western countries. Recent pre-clinical and clinical studies demonstrated that the combination of TCM and conventional cancer therapies had great benefits in terms of increasing the efficacy of chemotherapy and radiotherapy, decreasing harmful side effects, and improving the quality of life and survival time of cancer patients [28,29].

Jaeumganghwa-tang (JGT) is a traditional oriental herbal prescription, and it has been used for thousands of years in Eastern countries to discharge phlegm, suppress coughs, and treat symptoms such as hemoptysis, wheezing, night sweats, and facial flushing. Recent studies demonstrated that JGT inhibits the secretion of inflammatory cytokines such as TNF-α and interleukin-6 (IL-6) in human mast cells (HMC-1) by blocking NF-κB activation, supporting pharmacological role as a therapeutic agent for allergic inflammatory diseases [16]. In BPH rats induced by subcutaneous injection of TP, JGT administration significantly attenuated epithelial hyperplasia through reduction in levels of DHT (dihydrotestosterone) in serum as well as prostate and in the expression of PCNA (proliferating cell nuclear antigen) [17]. In addition, JGT administration improved hot flush caused by tamoxifen in breast cancer patients, while had no effect on the levels of female hormones such as follicle-stimulating hormone (FSH) or leuteinizing hormone (LH), showing evidence for efficacy and safety of JGT on the treatment of breast cancer patients [30]. Several herbs in JGT, including Angelicae Gigantis Radix, Citrus Unshiu peel, Asparagi Tuber, Anemarrhenae Rhizoma, and Paeoniae Radix, have demonstrated to exert anti-oxidant, anti-inflammatory, and anti-proliferative effects in cancer cell lines in vivo and in vitro [18, 31–33].

Recently, we demonstrated that the pharmacological activities of herbal medicines were improved by Lactobacillus fermentation. Fermenting soshiho-tang (FSST) using Lactobacillus plantarum enhanced its anti-proliferative activity in vascular smooth muscle cells [34]. Fermenting ssanghwa-tang (FSHT) using Lactobacillus fermentum resulted in a greater protective effect against CCl4-induced hepatotoxicity [35], and fermenting Hwangryun-Haedok-Tang (FHRT) using Lactobacillus casei suppressed ovariectomy-induced bone loss efficiently [36]. In addition, the Lactobacillus fermentation of Hwangryun-Haedok-Tang, Sipjeondaebotang, and Oyaksungisan enhanced their anti-inflammatory effects on LPS-stimulated RAW 264.7 cells remarkably [10,13,37].

The present study aimed to examine whether JGT exerted inhibitory effects on cancer cell growth and death, and then elucidated the detailed mechanism of action behind its anti-cancer activity. Furthermore, the anti-cancer potentials of non-fermented JGT and Lactobacillus-fermented JGT were compared. Our data clearly revealed that 500 and 1000 μg/mL JGT inhibited the growth of cancer cells efficiently by inducing G1 cell cycle arrest and ultimately inducing cell death by causing mitochondrial damage and caspase-dependent apoptosis. Studies using pharmacological inhibitors showed that p38 and ERK activation play roles in JGT-mediated cell death. In addition, an in vivo xenograft experiment showed that the daily administration of 120 mg/kg fJGT162 suppressed tumor growth to ~90% compared with saline, whereas 120 mg/kg aJGT suppressed tumor growth to ~70%, suggesting that Lactobacillus fermentation improved the in vivo anti-cancer activity of JGT considerably. In a previous study, we found that lactic bacterial fermentation modified the amounts of eight bioactive compounds of JGT: 5-HMF, paeoniflorin, nodakenin, hesperidin, nodakenetin, palmatine, berberine, and glycyrrhizin. In particular, the levels of most compounds were increased in fJGT162 compared with non-fermented JGT, although the levels of paeoniflorin and hesperidin were decreased [22]. Because nodakenin, nodakenetin, palmatine, berberine, and glycyrrhizin are well known anti-cancer agents [38-41], it is possible that the increased levels of these compounds in fJGT162 contributed to the enhanced anti-cancer activity. Moreover, fermentation can increase the in vivo absorption and bioavailability of JGT and subsequently potentiate its anti-cancer activity. In the toxicity study after single administration of JGT and fJGT162 at doses of 500, 1000, and 2000 mg/kg in ICR mice, we found no differences in body weight, organ weights, or serum chemistry profiles among saline-, JGT-, and fJGT162-treated mice, providing strong evidence for the safety of JGT and fJGT162 [42]. Moreover, repeated administration of JGT, aJGT, and fJGT162 at dose of 120 mg/kg during experimental period did not induce toxic side effects based on the body weight, organ weights, and serological and hematological parameters (S1–S4 Tables).

In summary, the current results demonstrated that JGT induced caspase-dependent apoptosis via mitochondrial damage and p38/ERK activation. Moreover, fermented JGT elicited much greater inhibitory effects on in vivo tumor growth compared with non-fermented JGT, without causing systemic toxicity. Collectively, these results suggest that JGT and fJGT162 are safe complementary and alternative herbal formula for controlling malignant tumor growth.

The effects of JGT on the cell viability and apoptotic morphological changes.

Human prostate cancer PC-3 cells and human gastric adenocarcinoma AGS cells were treated with the indicated doses of JGT for 48 h, and cell viability was determined using MTT assays. JGT-treated cells were observed under an inverted microscope (40× magnification). Data are representative of three independent experiments performed in triplicate and are expressed as means ± SD. * p < 0.05 vs. untreated control.

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JGT induces cell cycle arrest and apoptotic cell death in PC-3 cells.

PC-3 cells were treated with 1000 μg/mL JGT for 24 and 48 h, and the levels of cell cycle- and cell death-related proteins were examined by Western blotting. The band intensities relative to untreated cells were calculated using ImageJ software after normalization to tubulin expression.

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JGT induces activation of p38 and ERK in PC-3 cells.

PC-3 cells were treated with 1000 μg/mL JGT for 1, 3, and 6 h, and the levels of total and phosphorylated MAPKs were examined by Western blotting. The band intensities relative to untreated cells were calculated using ImageJ software after normalization to tubulin expression.

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aJGT and fJGT162 induce cell death in PC-3 and AGS cells.

PC-3 and AGS cells were treated with 250, 500, and 1000 μg/mL JGT for 48 h, and cell viability was determined using MTT assays and cell morphology was observed under an inverted microscope. Data are presented as means ± SD. * p < 0.05 vs. untreated control, # p < 0.05 vs. JGT or aJGT.

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Chromatograms of eight major standard compounds in JGT, aJGT, and fJG162.

A standard mixture of eight compounds in (a), JGT (b), aJGT (c), and fJGT162 (d) at 230 nm (A), 250 nm (B), 284 nm (C), and 330 nm (D) (UV). 5-HMF (1), paeoniflorin (2), glycyrrhizin (3), nodakenin (4), nodakenetin (5), berberine (6), palmatine (7), and hesperidin (8) were identified.

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Means of body weights of mice administered with saline, aJGT, and fJGT162.

Each group of mice (n = 3) were subjected to daily oral administration for 14 days and measured body weight every other day. Data are presented as mean ± SD.

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Organ weights of mice administered with saline, aJGT, and fJGT162.

Each group of mice (n = 3) were subjected to daily oral administration for 14 days. After sacrifice, organs were weighed and data are presented as mean ± SD.

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Chemical analysis of serums obtained from mice administered with saline, aJGT, and fJGT162.

Each group of mice (n = 3) were subjected to daily oral administration for 14 days. After sacrifice, serums were collected and then analyzed the levels of GOT, GPT, BUN, and CRE. Data are presented as mean ± SD. GOT, glutamic oxaloacetic transaminase; GPT, glutamic pyruvic transaminase; BUN, blood urea nitrogen; CRE, creatinine.

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Hematological analysis of bloods obtained from mice administered with saline, aJGT, and fJGT162.

Each group of mice (n = 3) were subjected to daily oral administration for 14 days. After sacrifice, whole bloods were collected and then analyzed hematologic parameters. Data are presented as mean ± SD. WBCP, white blood cell count peroxidase method; WBCB, white blood cell count basophil method; RBC, red blood cell count; HGB, hemoglobin; HCT, hematocrit; MCV, mean corpuscular volume; MCH, mean corpuscular hemoglobin; MCHC, mean corpuscular hemoglobin concentration; PLT, platelet.

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