The complete chloroplast genome of Geum longifolium (Maxim.) Smedmark 2006 (Rosaceae: Colurieae) and its phylogenomic implications.

Geum longifolium (Maxim.) Smedmark 2006 belongs to the family Rosaceae, subfamily Rosoideae, tribe Colurieae. Geum longifolium is endemic to China and its whole herb is used in Chinese medicine. Here, the first complete chloroplast (cp) genome of G. longifolium was assembled and annotated based on genome skimming, and its phylogenetic position was investigated using phylogenomic evidence. The cp genome size of G. longifolium was 155,884 bp with the total GC content of 36.7%. Its cp genome presented a typical tetrad structure, composed of a large single copy (LSC) region (85,338 bp), a small single copy (SSC) region (18,358 bp), and a pair of inverted repeat (IR) regions (26,094 bp). The cp genome encoded 129 genes, including 84 protein-coding genes, 37 tRNA genes, and eight rRNA genes. Phylogenetic analysis indicated that G. longifolium was sister to G. elatum Wall. ex G.Don 1832 in current taxa sampling. This study can enrich the chloroplast genomic resource of Geum and lay the foundation for future phylogenetic studies on Geum.

Furanodiene induces endoplasmic reticulum stress and presents antiproliferative activities in lung cancer cells.

Furanodiene (FUR) is a natural terpenoid isolated from Curcumae Rhizoma, a well-known Chinese medicinal herb that presents antiproliferation activities in several cancer cell lines. In this study, we demonstrated that FUR concentration dependently inhibits the cell proliferation of A549, NIH-H1299, and 95-D lung cancer cells. ß-elemene, another terpenoid isolated from Curcumae Rhizoma, exhibited weaker antiproliferative effects in A549 and NIH-H1299 cells and activities similar to FUR in 95-D cells. FUR significantly inhibited colony formation in A549 and 95-D cells and upregulated both the mRNA and protein expression levels of binding immunoglobulin protein (BIP) and C/EBP homologous protein (CHOP), indicating that endoplasmic reticulum (ER) stress is induced. FUR treatment led to the accumulation of CHOP in the nucleus, which further confirms induction of ER stress. Furthermore, combined treatment of FUR with paclitaxel showed significant synergetic activities in NIH-H1299 and 95-D cells, suggesting its potential roles in combination therapy. These findings provide a basis for the further study of the anticancer effects in vivo and the internal mechanisms of FUR.

[Inspirations from natural products based drug research and development for Chinese medicine research--analysis of natural products recoded in TTD].

Natural product is an important source of new drug research and development (R&D). Traditional Chinese medicine (TCM) innovation is the key step for its modernization and internationalization. However, due to the complexity of TCM, there are many difficulties and confusions in this process. Target-based drug discovery is the mainstream model and method of R&D. TTD, short for therapeutic target database, is developed by National University of Singapore. Besides a large amount of information on drug targets, the database also contains considerable information related to natural products. This paper briefly introduces the TTD, analyzes the natural products derived drugs/compounds recorded in TTD, which we think might provide some inspiration for the innovation of TCM.

[Effect of inhibition of Porphyromonas endodontalis on osteoblast differentiation].

PURPOSE: Porphyromonas endodontalis (P.e) is the dominant bacterium in the infected canal of pulpal and periapical disease.Lipopolysaccharides (LPS) in the outer membrane of the cell wall is an important toxicity factor of P.e. In this study, the effect of P.e-LPS on osteoblast differentiation was studied, and the pathogenic mechanism of P.e-LPS in periapical bone resorption disease was explored. METHODS: Porphyromonas endodontalis was cultured under anaerobic conditions. P.e-LPS was extracted by thermophenol water method, and then the extracted LPS was qualitatively analyzed by gel limulireagent method. Preosteoblast cell line MC3T3-E1 were induced to differentiate into osteoblasts by osteoblast differentiation medium (50 µg/mL ascorbic acid，6 mmol/L beta-glycerphosphate). Expressions of osteogenic differentiation genes including distal-less homeobox 5（DLX5）, runt-related transcription factor 2(Runx2), Osterix, bone sialoprotein (BSP), OCN(osteocalcin) and Collagen were detected by RT-PCR. The activity of alkaline phosphatase(ALP)， alizarin red staining and Von Kossa staining were used to determine the mineralization level of osteoblasts.The expression of TOLL-like receptor-4 (TLR-4), the receptor of P.e-LPS, was silenced by siRNA transfection. SPSS 11.0 software package was used for statistical analysis of the data. RESULTS: The mRNA expressions of osteogenic differentiation genes including DLX5, Runx2, Osterix, OCN, BSP, and Collagen were significantly decreased after treated with P.e-LPS (10 µg/mL) for 3 d, compared with the control group（P<0.05）.After treated with P.e-LPS (10 µg/mL) for 7 d or 14 d, respectively, ALP and alizarin red staining intensity was decreased. P.e-LPS was applied to the si-TLR-4 transfection group and the control group for 7,14 and 21 d, respectively. Compared with the control group, the expression level of osteogenic differentiation genes, ALP, alizarin red staining and Von Kossa staining intensity of si-TLR-4 group were significantly higher than those of the control group (P<0.05). CONCLUSIONS: P.e-LPS inhibits the differentiation of osteoblasts through TLR-4 receptor, thus participating in bone resorption process of periapical lesions.

[Comparison of mechanical properties of three machinable resin ceramic composite materials].

PURPOSE: This in vitro study was to compare the flexural properties, fracture toughness and hardness of three machinable composite materials. METHODS: Three kinds of resin composite ceramic Upcera Hyramic, 3M Lava Ultimate, Vita Enamic and a glass ceramic Vitablocs Mark II were chosen for the study. Bar-shaped specimens (16 mm×4 mm×1 mm, 2 mm) were prepared for flexural strength experiment; specimens (17 mm×4 mm×3 mm) were prepared for fracture toughness experiment and specimens of 4 mm thickness were prepared for hardness test. Flexural test and fracture toughness experiment were performed with an universal testing machine at a cross-head speed of 0.5 mm/min. Hardness test was performed with an micro hardness tester.Scanning electron microscope was used to observe the roughness of fracture surface. One-way variance analysis was used to determine the statistical differences with SPSS 17.0 software package. RESULTS: The mean flexural strength of the tested blocks at 1 mm thickness was Hyramic（207.7515±13.12）MPa＞Vita Enamic（182.0286±15.18）MPa＞Lava Ultimate（145.8469±8.98）MPa＞Vitablocs MarkⅡ（103.0542±18.19）MPa. The mean flexural modulus were Vitablocs MarkⅡ（49.49±5.50）GPa＞Vita Enamic（40.65±3.80）GPa＞Hyramic（14.89±2.38）GPa＞Lava Ultimate（7.09±1.24）GPa. The mean flexural strength of the tested blocks at 2 mm thickness was Hyramic（208.1986±25.07）MPa＞Lava Ultimate（172.9297±12.73）MPa＞Vitablocs MarkⅡ（158.6587±15.37） MPa＞Vita Enamic（155.3670±13.77）MPa. The mean flexural modulus were Vitablocs MarkⅡ（24.07±1.86）GPa＞Vita Enamic（19.64±0.98）GPa＞Hyramic（10.35±0.87）GPa＞Lava Ultimate（8.68±0.86）GPa. The mean fracture toughness was Vita Enamic（1.6357±0.16）MPa·m1/2＞Lava Ultimate（1.4286±0.11）MPa·m1/2>Vitablocs MarkII（1.3233±0.10）MPa·m1/2>Hyramic（1.0614±0.09）MPa·m1/2. The hardness of the experimental group was significantly lower than that of the control group. CONCLUSIONS: According to ISO 6872/2008, three kinds of machinable resin ceramic composites meet the needs of clinical strength.Hyramic showed higher flexural strength at different thickness, it is an ideal material for dental restoration. Vita Enamic has not only higher flexural strength at the thickness of 1 mm, but also good toughness, it is suitable for repair of patients that have limited occlusal space and great bite force, named occlusal veneer.

[Effects of Porphyromonas endodontalis lipopolysaccharides on the expression of monocyte chemotactic protein-1 in mouse osteoblasts].

PURPOSE: To investigate the effects of lipopolysaccharide (LPS) extracted from Porphyromonas endodontalis (P.endodontalis) on expression of monocyte chemotactic protein-1 (MCP-1) mRNA and protein in MC3T3-E1 cells and the role of p38 mitogen-activated　protein　kinase (MAPK) and nuclear factor-kB(NF-kB）in the process. METHODS: MC3T3-E1 cells were treated with different concentrations of P.endodontalis LPS(0-50mg/L) and 20 mg/L P.endodontalis LPS for different hours (0-48 h). The expression of MCP-1 mRNA was detected by real-time reverse transcription PCR(RT-PCR) and protein was detected by enzyme-1inked immunosorbent assay (ELISA). MC3T3-E1 cells were pretreated with SB203580 (inhibitor of p38MAPK) and BAY11-7082 (inhibitor of NF-kB) for 1h, and then were treated with 20 mg/L P.endodontalis LPS for 24 h, the expression of MCP-1 mRNA was also detected by RT-PCR. Statistical analysis was performed using one-way ANOVA and Dunnett t test with SPSS 13.0 software package. RESULTS: The level of MCP-1 mRNA and protein increased significantly after treatment with different concentrations of P.endodontalis LPS (0-50 mg/L), which indicated that P.endodontalis LPS induced osteoblasts to express MCP-1 in a dose dependent manners. During the observation time (0-48 h), the impact of 20 mg/L P.endodontalis LPS on induction of MCP-1 in MC3T3-E1 cells exhibited a time-dependent manner. The expression of MCP-1 mRNA decreased significantly after pretreated with 10 mol/L SB203580 and BAY11-7082 for 1 h,and the inhibitory effect of SB203580 was stronger than BAY11-7082. CONCLUSIONS: P.endodontalis LPS may induce the expression of MCP-1 mRNA and protein in MC3T3-E1 cells through the signaling pathway of p38MAPK and NF-kB.

[Inhibiting effect of transforming growth factor ß3 on IL-6 expression in MG63 induced by lipopolysaccharide].

PURPOSE: To explore the effect of transforming growth factor ß3 (TGF-ß3) on IL-6 expression in inflammatory MG63, and the mechanism by which TGF-ß3 exert its anti-inflammatory effect. METHODS: Cell line MG63 was stimulated by 20 µg/mL lipopolysaccharide of Porphyromonas endodontalis (P.e-LPS) to establish the inflammatory model of osteoblast. TGF-ß3 or TGFß1 varying from 5 to 20 ng/mL was added together with P.e-LPS for 24 h, then the mRNA expression of IL-6 was detected by real-time PCR, the role of TGF-ß3 on IL-6 protein was further verified by ELISA. MG63 was pretreated with 10 ng/mL TGF-ß3 for 30 min in RPMI 1640 medium without fetal bovine serum (FBS), then the cells were cultured for another 20 min with 20 µg/mL P.e-LPS, the phosphorylation level of ERK1/2 was measured by Western blot. Statistical analysis was performed using one-way ANOVA with SPSS13.0 software package. RESULTS: The results of real-time PCR revealed that, when MG63 was treated with 20 µg/mL P.e-LPS alone, the mRNA expression of IL-6 increased significantly(P<0.01). When TGF-ß1 was added with P.e-LPS, it could barely decrease IL-6 prominently at the highest concentration (P<0.05).Whereas, the inhibition effect of TGF-ß3 on IL-6 was dramatic (P<0.01), ELISA results showed that 10-20 ng/mL TGF-ß3 blocked the IL-6 expression at protein level (P<0.05). 20 µg/mL P.e-LPS promoted the phosphorylation level of ERK1/2 in MG63(P<0.01), while with 10 ng/mL TGF-ß3, the effect of P.e-LPS on ERK1/2 was blocked(P<0.05). CONCLUSIONS: TGF-ß3 is more potent than TGF-ß1 in inhibiting MG63, and ERK1/2 is involved in its anti-inflammatory effect.

[Effects of lipopolysaccharides from Porphyromonas endodontalis on the expression of MIP-1α in mouse osteoblasts].

PURPOSE: To investigate the effects of lipopolysaccharides(LPS) extracted from Porphyromonas endodontalis(P.e) on the expression of macrophageinflammatoryprotein-1α (MIP-1α) mRNA and protein levels in MC3T3-E1 cells and the influence of curcumin in the process. METHODS: MC3T3-E1 cells were treated with 20 mg/L P.e-LPS for different times (0-48 h). The expression of MIP-1α mRNA and protein was detected by real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) and enzyme linked immunosorbent assay(ELISA). MC3T3-E1 cells were pretreated with inhibitor of (curcumin) for 1 h, and then treated with 20 mg/L P.e-LPS. The expression of MIP-1α was also detected by real-time RT-PCR and ELISA.Statistical analysis was performed using one-way ANOVA and Dunnett's t test with SPSS 13.0 software package. RESULTS: In the observation time (0-48 h), the impact of 20 P.e-LPS mg/L on induction of MIP-1α in MC3T3-El cells exhibited a time-dependent manner. The expression of MIP-1α mRNA and protein decreased significantly after pretreatment with 10 µmol/L curcumin for 1 h. CONCLUSIONS: The results suggest that P.e-LPS may mediate MIP-1α expression in MC3T3-E1 cells, and curcumin has a significant inhibitory effect on this process.

[Effect of lipopolysaccharides from Porphyromonas endodontalis on the expression of interleukin-34 in mouse osteoblasts].

PURPOSE: To investigate the effects of lipopolysaccharides (LPS) extracted from Porphyromonas endodontalis (P.e) on the expression of interleukin-34 (IL-34) mRNA in MC3T3-E1 cells and the role of p38MAPK, ERK1/2, NF-κB and SIRT1 in the process. METHODS: MC3T3-E1 cells were treated with different concentrations of P.e-LPS(0-50 mg/L) and 20 mg/L P.e-LPS for different time (0-24 h). The expression of IL-34 mRNA was detected by real-time reverse transcription-polymerase chain reaction (real time RT-PCR). MC3T3-E1 cells were pretreated with inhibitor of NF-κB(BAY 11-7082),inhibitor of p38MAPK (SB203580), inhibitor of ERK1/2 (PD98059), agonist of sirtuin1 (SIRT1) [resveratrol (RES)] and inhibitor of SIRT1 (EX-527) for 1 h, and then were treated with 20 mg/L P.e-LPS. The expression of IL-34 mRNA was detected by real time RT-PCR. Statistical analysis was performed using one-way ANOVA and Dunnett t test with SPSS 13.0 software package. RESULTS: The level of IL-34 mRNA increased significantly after treatment with different concentrations of P.e-LPS(0-50 mg/L)，which indicated that P.e-LPS induced osteoblasts to express IL-34 mRNA in a dose-dependent manner. Maximal induction of IL-34 mRNA expression was observed in MC3T3-E1 cells treated with 20 mg/L P.e-LPS for 24 h.At 48 h, the expression of IL-34 mRNA decreased gradually. The mRNA of IL-34 decreased significantly after pretreatment with 10 µmol/L BAY-117082, SB203580 and PD98059 for 1 h. P.e-LPS-induced IL-34 upregulation was attenuated by pretreatment with RES, but increased by EX-527. CONCLUSIONS: These results suggest that P.e-LPS may mediate IL-34 mRNA expression in MC3T3-E1 cells. This process is dependent, at least in part, on p38MAPK, ERK1/2, NF-κB and SIRT1 signaling pathways.

[Mechanism of TNF-α in bone defect of chronic apical periodontitis].

PURPOSE: To investigate the effect of lipopolysaccharides(LPS) extracted from Porphyromonas endodontalis(P.e) on the expression of tumor necrosis factor-α(TNF-α) mRNA in MC3T3-E1 cells and the role of NF-κB signaling on the expression of macrophage colony stimulating factor (M-CSF) induced by TNF-α in MC3T3-El cells． METHODS: MC3T3-E1 cells were treated with different concentrations of P.e-LPS(0-50 mg/L) and 10 mg/L P.e-LPS for different time (0-24 h). The expression of TNF-α mRNA was detected by reverse transcription polymerase chain reaction(RT-PCR). MC3T3-E1 cells were treated with different concentrations of TNF-α(0-10 ng/L) for 6 h. The expression of M-CSF mRNA and protein was detected by RT-PCR and enzyme-linked immunoadsordent assay(ELISA).The expression of M-CSF protein was also detected in 10 ng/L TNF-α treated MC3T3-E1 cells after pretreated with BAY 11-7082 for 1 h, a special NF-κB inhibitor . Statistical analysis was performed using Multi-way ANOVA and Dunnett t test with SPSS 13.0 software package. RESULTS: The level of TNF-α mRNA increased significantly after treatment with different concentrations of P.e-LPS(0-50 mg/L)，which indicated that P.e-LPS induced osteoblasts to express TNF-α mRNA in dose dependent manners. Maximal induction of TNF-α mRNA expression was seen in the MC3T3-E1 cells treated with 10 mg/L P.e-LPS for 6 h. After 6 h, the expression of TNF-α mRNA decreased gradually .The expression of M-CSF mRNA and protein was increased in a does- dependent manner by different concentrations of TNF-α treatment（0-10 ng/L）. The expression of M-CSF protein increased from (37±2) ng/L(control group) to (301±8) ng/L(10 ng/L group).The protein of M-CSF decreased significantly after pretreatment with 10 µmol/L BAY 11-7082 for 1 h, and the expression of M-CSF proteins was reduced from (253±14) ng/L to (154±2) ng/L .BAY group had no significant difference from the control group. CONCLUSIONS: The expression of TNF-α mRNA was increased by P. endodontalis LPS treatment in osteoblast. TNF-α may induce the expression of M-CSF in MC3T3-E1 cells through the signaling of NF-κB. It suggests that TNF-α affect osteoblasts through autocrine way for bone destruction in chronic apical periodontitis induced by P.e-LPS.

[Effect of Ca(OH)2 on the cytotoxicity of lipopolysaccharide extracted from Porphyromonas endodontalis in vitro].

PURPOSE: To detect the degradation of Ca(OH)2 on lipopolysaccharide (LPS) extracted from Porphyromonas endodontalis (P.e) in vitro and estimate the influence of P.e LPS pretreated with Ca(OH)2 on the proliferation of MC3T3-E1 cells. METHODS: The effect of Ca(OH)2 on MC3T3-E1 cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay. Then P.e LPS was treated with Ca(OH)2 for 30 mins or 60 mins at 37 degrees centigrade in vitro and the activity of P.e LPS was evaluated by Chromogenic End-point Tachypleus Amebocyte Lysate (CE TAL) test. Finally, MC3T3-E1 cells were exposed to P.e LPS pretreated with 15% Ca(OH)2 for 1, 3 and 5 d, and the cell proliferation was measured using the MTT assay comparing with the P.e LPS control group. SPSS 13.0 software package was used for statistical analysis. RESULTS: Compared with the negative control, exposing cells to 5%, 10% and 15% Ca(OH)2 had greatly promoted MC3T3-E1 cell proliferation. P.e LPS treated with 10% and 15% Ca(OH)2 both presented the best results by CE TAL and significant difference compared with P.e LPS control group. When 10 µg/mL P.e LPS was pretreated with 15% Ca(OH)2, no inhibition of MC3T3-E1 cell proliferation was noted. CONCLUSIONS: Ca(OH)2 detoxifies P.e LPS in vitro, mitigates the impact of P.e LPS on MC3T3-E1 cell proliferation. Supported by Science and Technology Projects of Liaoning Province (2011225020).

[Effect of NF-κB on the expression of interleukin-6 induced by lipopolysaccharides of Porphyromonas endodontalis in MC3T3-E1 cells].

PURPOSE: To investigate the effect of NF-κB signaling on the expression of interleukin-6(IL-6) induced by lipopolysaccharides(LPS) extracted from Porphyromonas endodontalis(P.e) in MC3T3-El cells. METHODS: MC3T3-E1 cells were pretreated with BAY-117082 for 1 h, and then were treated with 10 mg/L P.e-LPS for different times. The translocation of NF-κB was observed by immunofluorescence. The expression of IL-6 was detected by reverse transcription polymerse chain reaction (RT-PCR) and enzyme-linked immuno sorbent assay (ELISA). Statistical analysis was performed using multi-way ANOVA and Dunnett's t test with SPSS 13.0 software package. RESULTS: The staining of NF-κB was mostly in cytoplasm in untreated cells. Rapid translocation of NF-κB into nucleus was observed in the cells stimulated for 30 min and mostly relocalization of NF-κB from nucleus to cytoplasm was observed after 60 min. Pretreatment with 10 µmol/L BAY-117082 for 1h significantly inhibited P.e-LPS-induced translocation of NF-κB .The mRNA and proteins of IL-6 decreased significantly after pretreatment with 10 µmol/L BAY-117082 and the expression of IL-6 proteins was reduced from (774.983±6.585) ng/L to (377.384±14.620) ng/L (P<0.01). The group of treatment with BAY-117082 alone had no significant difference from the blank control group. CONCLUSIONS: P.e-LPS can induce translocation of NF-κB in mouse osteoblast MC3T3-El, and P.e-LPS may induce the expression of IL-6 in mouse osteoblast through the signaling of NF-κB.

Anti-cancer properties of triterpenoids isolated from Ganoderma lucidum - a review.

INTRODUCTION: Triterpenoids isolated from Ganoderma lucidum are a class of naturally occurring compounds and structurally highly oxidized lanostanes. Accumulated data show that triterpenoids exhibit a broad spectrum of anti-cancer properties, including anti-proliferative, anti-metastatic and anti-angiogenic activities. A systematic summary and knowledge of future prospects are necessary to facilitate further studies on this species. AREAS COVERED: This review aims to summarize and analyze the current knowledge on the anti-cancer properties and mechanisms of G. lucidum triterpenoids (GLTs) and discuss the future prospects of the application of GLTs in cancer treatment. EXPERT OPINION: Extensive research over the last 10 years has provided evidence of the anti-cancer activities of GLTs in different stages of carcinogenesis. These activities include cell cycle arrest, induction of apoptosis and autophagy, and suppression of metastasis and angiogenesis. However, the exact molecular mechanisms involved in these processes remain unclear. Androgen receptor, nuclear factor-kappa B, activator protein-1, p53 and 14-3-3 are reportedly involved in the anti-cancer properties of GLTs. Animal models further shed light on the development of GLTs as anti-cancer agents. However, more research and clinical trials are necessary to exploit these compounds.

Synergistic anti-cancer activity of the combination of dihydroartemisinin and doxorubicin in breast cancer cells.

BACKGROUND: Dihydroartemisinin (DHA) exhibits potent anti-malarial and anti-cancer activities. This study aimed to investigate the anti-proliferative effects of a combination of DHA and doxorubicin (DOX) on human breast cancer cells. METHODS: MTT assay and the combination index (CI) were used to show the anti-proliferative effects and calculate the synergism potential, respectively. Flow cytometry assay was used to detect apoptosis and the intracellular accumulation of DOX. JC-1 staining was used to determine the mitochondrial membrane potential. Western blot analysis was used to detect the protein expression of some apoptosis-related molecules. RESULTS: Asynergistic anti-proliferative effect was found, and the enhanced anti-cancer activity was observed to be accompanied by the prompt onset of apoptosis in MCF-7 cells. The combinative treatment remarkably decreased the mitochondrial membrane potential and activated caspase cascades more than the mono-treatment. Pretreatment with DHA also did not influence the accumulation of DOX in MCF-7 cells. CONCLUSION: This study presented a new opportunity to enhance the effectiveness of future treatment regimens of breast cancer using DOX.

Ganoderiol A-enriched extract suppresses migration and adhesion of MDA-MB-231 cells by inhibiting FAK-SRC-paxillin cascade pathway.

Cell adhesion, migration and invasion are critical steps for carcinogenesis and cancer metastasis. Ganoderma lucidum, also called Lingzhi in China, is a traditional Chinese medicine, which exhibits anti-proliferation, anti-inflammation and anti-metastasis properties. Herein, GAEE, G. lucidum extract mainly contains ganoderiol A (GA), dihydrogenated GA and GA isomer, was shown to inhibit the abilities of adhesion and migration, while have a slight influence on that of invasion in highly metastatic breast cancer MDA-MB-231 cells at non-toxic doses. Further investigation revealed that GAEE decreased the active forms of focal adhesion kinase (FAK) and disrupted the interaction between FAK and SRC, which lead to deactivating of paxillin. Moreover, GAEE treatment downregulated the expressions of RhoA, Rac1, and Cdc42, and decreased the interaction between neural Wiskott-Aldrich Syndrome protein (N-WASP) and Cdc42, which impair cell migration and actin assembly. To our knowledge, this is the first report to show that G.lucidum triterpenoids could suppress cell migration and adhesion through FAK-SRC-paxillin signaling pathway. Our study also suggests that GAEE may be a potential agent for treatment of breast cancer.

Ganoderic acid DM, a natural triterpenoid, induces DNA damage, G1 cell cycle arrest and apoptosis in human breast cancer cells.

Ganoderic acid DM (GADM) is a triterpenoid isolated from Ganoderma lucidum, a well-known edible medicinal mushroom. In the present study, we found that GADM effectively inhibited cell proliferation and colony formation in MCF-7 human breast cancer cells, which was much stronger than that of MDA-MB-231 breast cancer cells. GADM both concentration- and time-dependently mediated G1 cell cycle arrest and significantly decreased the protein level of CDK2, CDK6, cycle D1, p-Rb and c-Myc in MCF-7 cells. Moreover, GADM obviously induced DNA fragmentation and cleavage of PARP which are the characteristics of apoptosis and decreased the mitochondrial membrane potential in MCF-7 cells. Besides, we also showed that GADM elicited DNA damage as measured by comet assay which is a sensitive method for DNA damage detection. γ-H2AX, a marker of DNA damage, was also slightly up-regulated after treated with GADM for 6h, suggesting that the G1 cell cycle arrest and apoptosis induced by GADM may be partially resulted from GADM-induced DNA damage. These results have advanced our current understandings of the anti-cancer mechanisms of GADM.