Scutellarin, a flavonoid compound from Scutellaria barbata, suppresses growth of breast cancer stem cells in vitro and in tumor-bearing mice.

BACKGROUND: Scutellaria barbata D. Don (SB), commonly known as Ban Zhi Lian and firstly documented by Shigong Chen, is a dried whole plant that has been studied for its therapeutic effects on breast cancer, colon cancer, and prostate cancer. Among its various compounds, scutellarin (SCU) has been demonstrated with anti-tumor effects. PURPOSE: This study aimed to evaluate the effects of SB water extract (SBW) and scutellarin on breast cancer stem cells (BCSCs), and to investigate their potential therapeutic effects on breast tumors in mice. METHODS: BCSCs were enriched from human breast cancer cells (MDA-MB-231 and MDA-MB-361) and their characteristics were analyzed. The effects of varying concentrations of SBW and scutellarin on cell viability, proliferation, self-renewal, and migration abilities were studied, along with the underlying mechanisms. The in vivo anti-tumor effects of scutellarin were further evaluated in SCID/NOD mice. Firstly, mice were inoculated with naïve BCSCs and subjected to treatment with scutellarin or vehicle. Secondly, BCSCs were pre-treated with scutellarin or vehicle prior to inoculation into mice. RESULTS: The derived BCSCs expressed CD44, CD133 and ALDH1, but not CD24, indicating that BCSCs have been successfully induced from both MDA-MB-231 and MDA-MB-361 cells. Both SBW and scutellarin reduced the viability, proliferation, sphere and colony formation, and migration of BCSCs. In mice with tumors derived from naïve BCSCs, scutellarin significantly reduced tumor growth, expression of proliferative (Ki67) and stem cell markers (CD44), and lung metastasis. In addition, pre-treatment with scutellarin also slowed tumor growth. Western blot results suggested the involvement of Wnt/ß-catenin, NF-κB, and PTEN/Akt/mTOR signaling pathways underlying the inhibitory effects of scutellarin. CONCLUSION: Our study demonstrated for the first time that both SB water extract and scutellarin could reduce the proliferation and migration of BCSCs in vitro. Scutellarin was shown to possess novel inhibitory activities in BCSCs progression. These findings suggest that Scutellaria barbata water extract, in particular, scutellarin, may have potential to be further developed as an adjuvant therapy for reducing breast cancer recurrence.

Natural product Eriocalyxin B suppressed triple negative breast cancer metastasis both in vitro and in vivo.

Breast cancer is the most commonly diagnosed cancer among women, and its metastasis to distant organs accounts for the majority of death. Eriocalyxin B (Eri B), an ent-kaurane diterpenoid isolating from Isodon eriocalyx var. laxiflora, has previously been reported to have anti-tumor and anti-angiogenic effects in breast cancer. Here, we investigated the effect of Eri B on cell migration and adhesion in triple negative breast cancer (TNBC) cells, as well as aldehyde dehydrogenases 1 family member A1 (ALDH1A1) expression, colony- and sphere-formation in cancer stem cell (CSC) enriched MDA-MB-231 cells. The in vivo anti-metastatic activities of Eri B were determined in 3 different breast tumor-bearing mouse models. Our results indicated that Eri B inhibited TNBC cell migration and adhesion to extracellular matrix proteins, and also reduced ALDH1A1 expression and colony formation in CSC-enriched MDA-MB-231 cells. The metastasis-related pathways, such as epidermal growth factor receptor/ mitogen-activated protein kinase kinases 1/2/ extracellular regulated protein kinase signaling altered by Eri B was firstly shown in MDA-MB-231 cells. The potent anti-metastatic efficacies of Eri B were demonstrated in breast xenograft-bearing mice and syngeneic breast tumor-bearing mice. Gut microbiome analysis results revealed the change in the diversity and composition of microbiome after Eri B treatment, and the potential pathways that are involved in the anti-cancer efficacy of Eri B. In conclusion, Eri B was shown to inhibit breast cancer metastasis in both in vitro and in vivo models. Our findings further support the development of Eri B as an anti-metastatic agent for breast cancer.

Anti-inflammatory activities of natural cyclopeptide RA-XII in colitis-associated colon cancer mouse model and its effect on gut microbiome.

Colorectal cancer (CRC), the third most common cancer globally, is associated with intestinal inflammation that leads to poor prognosis. RA-XII, a natural cyclopeptide, has previously been reported to possess anti-tumor activities. Here, the anti-inflammatory activities of RA-XII were investigated in colitis-associated colon cancer mice and a co-culture in vitro model, in which colon cancer cells HCT116 and macrophages RAW264.7 were grown together to mimic the inflammatory microenvironment of CRC. Changes of inflammatory-related molecules and protein expressions in cells were evaluated after RA-XII incubation. Besides, azoxymethane and dextran sulfate sodium-induced colitis-associated colon cancer mice were treated with RA-XII for 24 days, inflammatory parameters and gut microbiome alterations were studied. Our results showed that RA-XII reversed the inflammatory responses of RAW264.7 cells induced by LPS and modulated the protein expressions of AKT, STAT3/p-STAT3, P70S6K, NF-κB and GSK3ß and suppressed the expression of LC3A/B in HCT116 cells in co-culture system. RA-XII treatment restored the colitis damage in colon, reduced colon tumors numbers and decreased inflammatory factors (IL-6, IL-10 and TNF-α). The role of RA-XII on regulating gut microbiome was also demonstrated for the first time. In conclusion, our findings provided new scientific evidence for developing RA-XII as a potent anti-inflammatory agent for CRC.

Network pharmacology reveals potential functional components and underlying molecular mechanisms of Andrographis paniculata in esophageal cancer treatment.

Antitumor and antimetastatic effects of the medicinal herb Andrographis paniculata (AP) in esophageal cancer (EC) have been previously reported. In this study, we aimed to uncover the potential functional components and the underlying molecular mechanisms of AP in EC treatment using network pharmacology and experimental validation. Twenty-two potential active AP compounds against EC were revealed, including the antitumor/antiinflammatory compounds panicolin, moslosooflavone, and deoxyandrographiside. Epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT3), RAC-alpha serine/threonine-protein kinase (AKT1), prostaglandin-endoperoxide synthase 2 (PTGS2), chemokine (C-X-C motif) ligand 8 (CXCL8), phosphatidylinositol 4,5-bisphosphate 3-kinase subunit alpha (PIK3CA), and toll-like receptor 4 (TLR4) were most highly ranked among the predicted targets of AP in EC treatment and may play important roles in the anti-EC effects of AP. KEGG pathway analysis revealed the enrichment of multiple cancer-related pathways and signaling pathways. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting validation showed that overnight treatment with 850.3 µg/ml of AP water extract significantly reduced the mRNA expressions of EGFR and AKT in human EC-109 cells. The presence of panicolin and moslosooflavone in the AP water extract samples were confirmed using LC-MS against reference standards. This study has comprehensively revealed for the first time the potential functional components of AP in EC and explored the underlying molecular mechanisms. Future studies should characterize the potential pharmacological properties of the other highly ranked yet understudied compounds in AP detected.

Natural flavone tricin exerted anti-inflammatory activity in macrophage via NF-κB pathway and ameliorated acute colitis in mice.

BACKGROUND: Ulcerative colitis is a subtype of inflammatory bowel disease, characterized by relapsing inflammation in the gastrointestinal tract with limited treatment options. Previous studies suggested that the natural compound tricin, a flavone isolated from rice bran, could suppress chemically-induced colitis in mice, while our recent study also demonstrated the anti-metastatic effect of tricin in colon tumor-bearing mice. HYPOTHESIS/PURPOSE: Here we further investigated the underlying mechanism of the inhibitory effects of tricin on lipopolysaccharides-activated macrophage RAW264.7 cells and explored the efficacy of tricin in acute colitis mouse model induced by 4.5% dextran sulfate sodium (DSS) for 7 days. METHODS: Tricin (75, 100, and 150 mg/kg) or the positive control drug sulfasalazine (200 mg/kg) were orally administered to mice for 7 days. Stool consistency scores, stool blood scores, and body weight were recorded daily. Disease activity index (DAI) was examined on day 7, and colon tissues were collected for biochemical analyses. The fecal microbiome of colitis mice after tricin treatment was characterized for the first time in this study using 16S rDNA amplicon sequencing. RESULTS: Results showed that tricin (50 µM) remarkably reduced nitric oxide production in lipopolysaccharides-activated RAW264.7 cells and the anti-inflammatory activity of tricin was shown to act through the NF-κB pathway. Besides, tricin treatment at 150 mg/kg significantly reversed colon length reduction, reduced myeloperoxidase activities and DAI scores, as well as restored the elevated myeloid-derived suppressive cells population in acute colitis mice. The influence from DSS on gut microbiota, such as the increased population of Proteobacteria phylum and Ruminococcaceae family, was shown to be relieved after tricin treatment. CONCLUSION: Our present study firstly demonstrated that tricin ameliorated acute colitis by improving colonic inflammation and modulating gut microbiota profile, which supports the potential therapeutic use of tricin for colitis treatment.

Effectiveness of Scutellaria barbata water extract on inhibiting colon tumor growth and metastasis in tumor-bearing mice.

The plant Scutellaria barbata (SB) is commonly used as herbal medicines for treating cancer. The present pre-clinical study aimed to validate the Chinese Pharmacopoeia (CP) recommended dosages of SB water extract (SBW) in treating colon tumors. The content of chemical marker scutellarin in SBW was quantified using UPLC. Mice bearing human HCT116 xenografts or murine colon26 tumors received oral administration of SBW or scutellarin for 4 weeks. Results showed that SBW (615 and 1,230 mg/kg) and scutellarin (7 mg/kg) treatments significantly reduced human xenograft weights by 28.7, 36.9 and 28.8%, respectively. Lung metastasis area could be ameliorated after SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments by 23.4 and 29.5%, respectively. Expressions of colon cancer metastasis-related proteins E-cadherin, Tspan 8 and CXCR4, as well as Src kinase in tumors were first shown to be regulated by SBW. Furthermore, in murine colon26 tumor-bearing mice, SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments reduced the orthotopic tumor burden by 94.7% and lung metastatic tumor burden by 94.1%, respectively. Our findings provided evidences that SBW (at the mouse equivalent dosages to clinical dosages recommended by CP) could exert anti-tumor and anti-metastatic effects in colon cancer animal models.

A Natural Flavone Tricin from Grains Can Alleviate Tumor Growth and Lung Metastasis in Colorectal Tumor Mice.

Tricin, a flavone isolated from rice bran, has been shown to be chemopreventive in a colorectal cancer (CRC) mouse model. This study aimed to illustrate the inhibitory activities of tricin in colon cancer cells and in a metastatic CRC mouse model. BALB/c mice injected with mouse Colon26-Luc cells into the rectum wall were treated with tricin (37.5 mg/kg) daily for 18 days. Orthotopic colon tumor growth and metastasis to lungs were assessed by in vivo bioluminescence imaging. Results showed that tricin suppressed Colon-Luc cells motility and downregulated phosphorylated Akt, Erk1/2 and NF-κB expressions of human colon cancer HT-29 cells. While tricin treatment suppressed tumor growth and lung metastasis as well as altered the populations of myeloid-derived suppressor cells and regulatory T cells in spleens. In summary, the tumor microenvironment modulatory and anti-metastatic effects of tricin in colon cancer mouse model were shown for the first time, suggesting the potential development of tricin-containing food supplements for CRC patients.

Immunomodulatory and antitumour bioactive labdane diterpenoids from Leonurus japonicus.

OBJECTIVES: Two labdane diterpenoids, leojapone B and heteronone B, were isolated from Leonurus japonicus Houtt., and their biological activity were evaluated in this study. METHODS: Human and mouse cancer cells, human peripheral blood mononuclear cells (PBMCs) and mouse macrophages (RAW264.7 cells) were used to evaluate the activity of leojapone B and heteronone B, while the in vivo effects of leojapone B were further examined in Lewis Lung Cancer tumour-bearing mice. KEY FINDINGS: In vitro studies showed that leojapone B selectively inhibited the proliferation of lung cancer cells, and both leojapone B and heteronone B inhibited the production of pro-inflammatory cytokines in activated PBMCs. In tumour-bearing mice model, lung tumours were reduced in size in mice treated with intraperitoneal injections of leojapone B at 20 and 30 mg/kg for 14 days. The population ratio of CD4+ /CD8+ T cells in mouse spleens was found to be increased, while regulatory T cells were decreased after leojapone B treatment. CONCLUSIONS: The inhibitory effects of leojapone B in mouse lung tumours were demonstrated for the first time in this study. The immunomodulatory activity of heteronone B were also demonstrated. Our findings indicated that both leojapone B and heteronone B may act as active components in L. japonicus.

Multiple modulatory activities of Andrographis paniculata on immune responses and xenograft growth in esophageal cancer preclinical models.

BACKGROUND: Esophageal cancer (EC) is a malignant gastrointestinal cancer with high morbidity worldwide and is the fourth leading cause of cancer-related deaths in China. Even though surgery and/or chemotherapy/chemoradiation might achieve good therapeutic response, recurrence rate is high due to cancer metastasis. Hence, the use of alternative adjuvant treatments, such as herbal medicines, for metastatic EC remains a great desire of the patients. Our previous studies have demonstrated the anti-metastatic efficacy of hot water extract of Andrographis paniculata (APW) in human esophageal cancer cells and tumor-bearing nude mice. PURPOSE: In the present study, the immunomodulatory activities of APW were further evaluated in human peripheral blood mononuclear cells (PBMCs) and in a carcinogen-induced esophageal tumorigenesis model using immune-competent C57BL/6 mice. Besides, the inhibitory effects of APW on esophageal cancer cell line-based xenografts and patient-derived xenografts (PDX) were examined so as to illustrate the potential multi-targeted efficacies of APW in esophageal cancer in pre-clinical models. RESULTS: In vitro results showed that APW could stimulate proliferation of PBMCs, as well as TNF-α and IFN-γproductions. In mice with 4-nitroquinoline 1-oxide-induced tumorigenesis, 21-day oral treatment with APW (1600 mg/kg) decreased the level of dysplasia in esophagus and significantly modulated the population of regulatory T cells. The cytokines productions by spleen lymphocytes of APW-treated mice were shifted towards normal resting state (i.e. unchallenged with carcinogen). Furthermore, APW treatment suppressed the growth of cell line-based xenografts by significantly increasing apoptosis in tumors, without causing severe body weight loss as chemotherapeutics did. Most importantly, the inhibitory effects of APW treatment on esophageal patient-derived xenografts growth were demonstrated for the first time. Besides, several diterpenes were detected in the plasma after oral administration of APW in mice, suggesting that multi-components of APW were bioavailable and might have contributed towards the varied pharmacological activities demonstrated in our studies. CONCLUSION: APW was shown to possess anti-tumor, anti-metastatic and immunomodulatory activities in esophageal cancer cell-based and animal models, including immunocompromised mice model and clinically relevant PDX model. Our findings illustrated the potential multi-targeted efficacies of APW in esophageal cancer management.

Gene expression profiling reveals the plausible mechanisms underlying the antitumor and antimetastasis effects of Andrographis paniculata in esophageal cancer.

Esophageal cancer (EC) is a seriously invasive malignancy with high mortality and poor prognosis. Metastasis of EC is the major cause of mortality. Our studies previously demonstrated that a herbal medicine Andrographis paniculata (AP) significantly suppressed EC growth and metastasis in vitro and in vivo. However, the underlying mechanisms responsible for these effects have not yet been systematically elucidated. In this context, gene expression profiling of AP-treated squamous EC cells (EC-109) was performed to reveal the regulatory mechanisms of AP in antitumor and antimetastasis signaling pathways using gene expression microarray analysis. Differentially expressed genes were identified by Affymetrix Gene Chip, followed by the real-time polymerase chain reaction validation. The results showed that the canonical pathways were significantly regulated by AP treatment, including multiple genes related to proliferation, apoptosis, intercellular adhesion, metastatic processes, and drug resistance, such as WNT, TGF-ß, MAPK and ErbB signaling pathways, and ATP-binding cassette transporter subfamily members. This genomic study emerges candidate molecular targets and pathways to reveal the mechanisms involved in AP's effects, which provides scientific evidence to support the clinical application of AP in EC treatment.

Natural small molecule bigelovin suppresses orthotopic colorectal tumor growth and inhibits colorectal cancer metastasis via IL6/STAT3 pathway.

Bigelovin, a sesquiterpene lactone, has been demonstrated to induce apoptosis, inhibit inflammation and angiogenesis in vitro, but its potential anti-metastatic activity remains unclear. In the present study, two colon cancer mouse models, orthotopic tumor allografts and experimental metastatic models were utilized to investigate the progression and metastatic spread of colorectal cancer after bigelovin treatments. Results showed that bigelovin (intravenous injection; 0.3-3 mg/kg) significantly suppressed tumor growth and inhibited liver/lung metastasis with modulation of tumor microenvironment (e.g. increased populations of T lymphocytes and macrophages) in orthotopic colon tumor allograft-bearing mice. Furthermore, the inhibitory activities were also validated in the experimental human colon cancer metastatic mouse model. The underlying mechanisms involved in the anti-metastatic effects of bigelovin were then revealed in murine colon tumor cells colon 26-M01 and human colon cancer cells HCT116. Results showed that bigelovin induced cytotoxicity, inhibition of cell proliferation, motility and migration in both cell lines, which were through interfering IL6/STAT3 and cofilin pathways. Alternations of the key molecules including Rock, FAK, RhoA, Rac1/2/3 and N-cadherin, which were detected in bigelovin-treated cancer cells, were also observed in the tumor allografts of bigelovin-treated mice. These findings strongly indicated that bigelovin has potential to be developed as anti-tumor and anti-metastatic agent for colorectal cancer.

An innovative anti-cancer Chinese herbal formula exhibited multi-targeted efficacies in metastatic breast cancer mouse model.

BACKGROUND: The incidence and mortality of cancer metastasis is high worldwide. Despite of the chemotherapeutic agents, many cancer patients still take traditional Chinese herbal prescriptions as adjuvant treatments. However, most of these herbal formulae/products lack of evidence-based efficacy. Based on our previous investigations on anti-tumor, anti-angiogenic, anti-metastatic, bone protective and immunomodulating activities of various Chinese herbal medicines, four constituent herbs, namely Andrographis paniculata, Acanthopanax senticosus, Camellia sinensis, and Hedyotis diffusa were eventually selected to form an innovative herbal formula. METHODS: The anti-tumor efficacies of the formula were evaluated in metastatic breast cancer mice model. The bone protective and immunomodulatory effects were also assessed after formula treatment. RESULTS: Our results showed that the breast tumor weight as well as lung and liver metastasis in mice could be reduced after herbal formula treatment for 4 weeks. The breast tumor-induced osteolysis in mice was restored by herbal formula treatment, in which the bone volume in treated mice tibia was comparable to that in the non-tumor bearing normal mice. The IL-12 level was augmented and the survival of mice with metastatic breast tumors was prolonged after treatment. Furthermore, combination of herbal formula with chemotherapeutic agent doxorubicin resulted in better anti-tumor efficacy and increased life span in tumor-bearing mice, when compared with doxorubicin alone treatment. CONCLUSIONS: In summary, our innovative Chinese herbal formula was demonstrated to possess anti-tumor, anti-metastatic and bone-protective activities in metastatic breast tumor-bearing mice. The preclinical data generated in this study would lead to the development of evidence-based supplement as adjuvant therapy for metastatic breast cancer.

The adjuvant value of Andrographis paniculata in metastatic esophageal cancer treatment - from preclinical perspectives.

Esophageal cancer (EC) is the fourth and sixth leading cause of cancer-related deaths in China and United States, respectively. The dismal prognosis of EC is mainly attributed to distant metastases, which may not be overcome by chemotherapy alone. Hence, the use of alternative adjuvant treatments, such as herbal medicines, for metastatic EC remains a great desire of patients. Our previous study demonstrated the in vivo anti-tumor and in vitro anti-invasion activities of Andrographis paniculata (AP) in esophageal cancer. In the present study, the chemical constituents of absorbed AP components through human intestinal Caco-2 cell monolayer were verified for the first time. The anti-migratory activities and suppressive effects on metastasis-related factors such as HER2, MMP2, MMP9, TM4SF3, CXCR4 of the absorbed AP components were revealed in esophageal cancer cells EC-109. The anti-tumor and anti-metastatic effects of AP water extract (1600 mg/kg) were further confirmed in metastatic esophageal xenograft-bearing mice. Besides, AP water extract acted synergistically with cisplatin plus 5-fluorouracil on inhibiting tumor nodule growth (with combination index <0.7). Meanwhile, chemotherapeutics-induced side-effects could also be reduced by AP water extract. The present findings provide evidence on safety and advantages of the combined use of AP with chemotherapeutics in pre-clinical setting.

Evaluation of the combined use of metronomic zoledronic acid and Coriolus versicolor in intratibial breast cancer mouse model.

ETHNOPHARMACOLOGICAL RELEVANCE: Coriolus versicolor (CV) is a mushroom traditionally used for strengthening the immune system and nowadays used as immunomodulatory adjuvant in anticancer therapy. Breast cancer usually metastasizes to the skeleton, interrupts the normal bone remodeling process and causes osteolytic bone lesions. The aims of the present study were to evaluate its herb-drug interaction with metronomic zoledronate in preventing cancer propagation, metastasis and bone destruction. MATERIALS AND METHODS: Mice inoculated with human breast cancer cells tagged with a luciferase (MDA-MB-231-TXSA) in tibia were treated with CV aqueous extract, mZOL, or the combination of both for 4 weeks. Alteration of the luciferase signals in tibia, liver and lung were quantified using the IVIS imaging system. The skeletal response was evaluated using micro-computed tomography (micro-CT). In vitro experiments were carried out to confirm the in vivo findings. RESULTS: Results showed that combination of CV and mZOL diminished tumor growth without increasing the incidence of lung and liver metastasis in intratibial breast tumor model. The combination therapy also reserved the integrity of bones. In vitro studies demonstrated that combined use of CV and mZOL inhibited cancer cell proliferation and osteoclastogenesis. CONCLUSIONS: These findings suggested that combination treatment of CV and mZOL attenuated breast tumor propagation, protected against osteolytic bone lesion without significant metastases. This study provides scientific evidences on the beneficial outcome of using CV together with mZOL in the management of breast cancer and metastasis, which may lead to the development of CV as adjuvant health supplement for the control of breast cancer.

Screening and analysis of potential anti-tumor components from the stipe of Ganoderma sinense using high-performance liquid chromatography/time-of-flight mass spectrometry with multivariate statistical tool.

According to Chinese Pharmacopoeia 2015 edition, Ganoderma (Lingzhi) is a species complex that comprise of Ganoderma lucidum and Ganoderma sinense. The bioactivity and chemical composition of G. lucidium had been studied extensively, and it was shown to possess antitumor activities in pharmacological studies. In contrast, G. sinense has not been studied in great detail. Our previous studies found that the stipe of G. sinense exhibited more potent antitumor activity than the pileus. To identify the antitumor compounds in the stipe of G. sinense, we studied its chemical components by merging the bioactivity results with liquid chromatography-mass spectrometry-based chemometrics. The stipe of G. sinense was extracted with water, followed by ethanol precipitation and liquid-liquid partition. The resulting residue was fractionated using column chromatography. The antitumor activity of these fractions were analysed using MTT assay in murine breast tumor 4T1 cells, and their chemical components were studied using the LC-QTOF-MS with multivariate statistical tools. The chemometric and MS/MS analysis correlated bioactivity with five known cytotoxic compounds, 4-hyroxyphenylacetate, 9-oxo-(10E,12E)-octadecadienoic acid, 3-phenyl-2-propenoic acid, 13-oxo-(9E,11E)-octadecadienoic acid and lingzhine C, from the stipe of G. sinense. To the best of our knowledge, 4-hyroxyphenylacetate, 3-phenyl-2-propenoic acid and lingzhine C are firstly reported to be found in G. sinense. These five compounds will be investigated for their antitumor activities in the future.

Bigelovin triggered apoptosis in colorectal cancer in vitro and in vivo via upregulating death receptor 5 and reactive oxidative species.

Colorectal cancer (CRC) is the third most prevalent cancer and the third highest cancer-related mortality in the United States. Bigelovin, a sesquiterpene lactone isolated from Inula helianthus aquatica, has been proven to induce apoptosis and exhibit anti-inflammatory and anti-angiogenic activities. However, the effects of bigelovin on CRC and underlying mechanisms have not been explored. The present study demonstrated that bigelovin exhibited potent anti-tumor activities against CRC in vitro and in vivo. Bigelovin suppressed cell proliferation and colony formation and induced apoptosis in human colorectal cancer HT-29 and HCT 116 cells in vitro. Results also revealed that bigelovin activated caspases, caused the G2/M cell cycle arrest and induced DNA damage through up-regulation of death receptor (DR) 5 and increase of ROS. In HCT 116 xenograft model, bigelovin treatment resulted in suppression of tumor growth. Bigelovin at 20 mg/kg showed more significant tumor suppression and less side effects than conventional FOLFOX (containing folinic acid, 5-fluorouracil and oxaliplatin) treatment. In addition, in vivo data confirmed that anti-tumor activity of bigelovin in CRC was through induction of apoptosis by up-regulating DR5 and increasing ROS. In conclusion, these results strongly suggested that bigelovin has potential to be developed as therapeutic agent for CRC patients.

New potential beneficial effects of actein, a triterpene glycoside isolated from Cimicifuga species, in breast cancer treatment.

Actein is a triterpene glycoside isolated from the rhizomes of Cimicifuga foetida (Chinese herb "shengma") which could inhibit the growth of breast cancer cells. Nevertheless, the effect of actein on angiogenesis, which is an essential step for tumor growth and metastasis, has never been reported. Hence, this study aimed to investigate the in vitro and in vivo effects of actein on angiogenesis using human microvascular endothelial cells (HMEC-1), matrigel plug and tumor-bearing mouse models. Our results showed that actein significantly inhibited the proliferation, reduced the migration and motility of endothelial cells, and it could suppress the protein expressions of VEGFR1, pJNK and pERK, suggesting that JNK/ERK pathways were involved. In vivo results showed that oral administration of actein at 10 mg/kg for 7 days inhibited blood vessel formation in the growth factor-containing matrigel plugs. Oral actein treatments (10-15 mg/kg) for 28 days resulted in decreasing mouse 4T1 breast tumor sizes and metastasis to lungs and livers. The apparent reduced angiogenic proteins (CD34 and Factor VIII) expressions and down-regulated metastasis-related VEGFR1 and CXCR4 gene expressions were observed in breast tumors. Our novel findings provide insights into the use of actein for development of anti-angiogenic agents for breast cancer.

Eriocalyxin B, a natural diterpenoid, inhibited VEGF-induced angiogenesis and diminished angiogenesis-dependent breast tumor growth by suppressing VEGFR-2 signaling.

Eriocalyxin B (EriB), a natural ent-kaurane diterpenoid isolated from the plant Isodon eriocalyx var. laxiflora, has emerged as a promising anticancer agent. The effects of EriB on angiogenesis were explored in the present study. Here we demonstrated that the subintestinal vein formation was significantly inhibited by EriB treatment (10, 15 µM) in zebrafish embryos, which was resulted from the alteration of various angiogenic genes as shown in transcriptome profiling. In human umbilical vein endothelial cells, EriB treatment (50, 100 nM) could significantly block vascular endothelial growth factors (VEGF)-induced cell proliferation, tube formation, cell migration and cell invasion. Furthermore, EriB also caused G1 phase cell cycle arrest which was correlated with the down-regulation of the cyclin D1 and CDK4 leading to the inhibition of phosphorylated retinoblastoma protein expression. Investigation of the signal transduction revealed that EriB inhibited VEGF-induced phosphorylation of VEGF receptor-2 via the interaction with the ATP-binding sites according to the molecular docking simulations. The suppression of VEGFR-2 downstream signal transduction cascades was also observed. EriB was showed to inhibit new blood vessel formation in Matrigel plug model and mouse 4T1 breast tumor model. EriB (5 mg/kg/day) treatment was able to decrease tumor vascularization and suppress tumor growth and angiogenesis. Taken together, our findings suggested that EriB is a novel inhibitor of angiogenesis through modulating VEGFR-2 signaling pathway, which could be developed as a promising anti-angiogenic agent for treatment of angiogenesis-related human diseases, such as cancer.

Melodinine V, an antitumor bisindole alkaloid with selective cytotoxicity from Melodinus henryi.

Melodinine V (1) with a vincanol-eburenine skeleton, was isolated from Melodinus henryi. The structure was elucidated by extensive spectroscopic methods and further confirmed by the single crystal X-ray diffraction analysis. Melodinine V showed selective cytotoxic activities against human colon cancer cell line HT-29 and inhibited cell proliferation in a concentration-dependent manner. It induced cell cycle arrest at G1 phase and cellular apoptosis by increasing histone-associated DNA fragmentation in the treated HT-29 cells.

Combined therapy using bevacizumab and turmeric ethanolic extract (with absorbable curcumin) exhibited beneficial efficacy in colon cancer mice.

Turmeric is commonly used as a medicinal herb and dietary supplement. Its active ingredient, curcumin, has been shown to possess antitumor effects in colorectal cancer patients. However, poor absorption of curcumin in intestine impedes its wide clinical application. Our previous findings showed that the presence of turmerones increased the accumulation of curcumin inside colonic cells. Hence, we hypothesized that curcumin with turmerones or present in turmeric ethanolic extract would augment its anti-tumor activities in tumor-bearing mice. The pharmacokinetics of curcumin in different preparations (containing same amount of curcumin) were studied in mice. The anti-tumor efficacies of curcumin or turmeric extract (with absorbable curcumin) in combination with bevacizumab were further investigated in HT29 colon tumor-bearing mice. Pharmacokinetic results showed that the plasma curcumin level of turmeric extract-fed mice was the highest, suggesting turmeric extract had the best bioavailability of curcumin. Besides, combined turmeric extract plus bevacizumab treatment significantly inhibited the tumor growth. Such inhibitory effects were stronger than those of curcumin plus bevacizumab or bevacizumab alone and were comparable with those of 5-fluorouracil+leucovorin+oxaliplatin (FOLFOX) plus bevacizumab. Notably, there was no observable side effect induced by turmeric extract treatment while significant side effects were found in FOLFOX-treated mice. In conclusion, combination of turmeric extract with bevacizumab possessed potent anti-tumor effects without observable side effects, strongly suggesting the adjuvant use of turmeric extract in colorectal cancer therapy. Our current findings warrant the confirmation regarding the benefits arising from the combined use of bevacizumab and turmeric in colorectal cancer patients in the near future.