Platycodin D Inhibits Vascular Endothelial Growth Factor-Induced Angiogenesis by Blocking the Activation of Mitogen-Activated Protein Kinases and the Production of Interleukin-8.

Platycodin D is a major constituent in the root of Platycodon grandiflorum and has diverse pharmacologic activities, including anti-inflammatory, anti-allergic, and antitumor activities. Vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) are potent angiogenic factors and contribute to tumor angiogenesis by directly and indirectly promoting angiogenic processes, including the proliferation, adhesion, migration, and tube formation of endothelial cells. Here, we found that platycodin D at noncytotoxic concentrations inhibited VEGF-induced proliferation, adhesion to the extracellular matrix proteins fibronectin and vitronectin, chemotactic motility, and tube formation of human umbilical vein endothelial cells (HUVECs). Platycodin D reduced the phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK) and the secretion of IL-8 in VEGF-stimulated HUVECs. Moreover, platycodin D inhibited tube formation and the phosphorylation of ERK and p38 in IL-8-stimulated HUVECs. The in vitro anti-angiogenic activity of platycodin D was confirmed by in vivo experimental models. Platycodin D inhibited the formation of new blood vessels into mouse Matrigel plugs with VEGF or IL-8. In mice injected with MDA-MB-231 human breast cancer cells, orally administered platycodin D inhibited tumor growth, the number of CD34 [Formula: see text]vessels, and the expression of VEGF and IL-8. Taken together, platycodin D directly and indirectly prevents VEGF-induced and IL-8-induced angiogenesis by blocking the activation of mitogen-activated protein kinases (MAPKs). Platycodin D may be beneficial for the prevention or treatment of tumor angiogenesis and angiogenesis-related human diseases.

Xanthorrhizol Suppresses Vascular Endothelial Growth Factor-Induced Angiogenesis by Modulating Akt/eNOS Signaling and the NF-[Formula: see text]B-Dependent Expression of Cell Adhesion Molecules.

Angiogenesis plays a crucial role in tumor growth and metastasis. Vascular endothelial growth factor (VEGF)-stimulated endothelial cell proliferation and migration are critical steps in tumor angiogenesis. Here, we investigated the anti-angiogenic activity of xanthorrhizol, a sesquiterpenoid isolated from the Indonesian medicinal plant Curcuma xanthorrhiza. Xanthorrhizol at noncytotoxic concentrations inhibited the proliferation, migration, and formation of capillary-like tubes in VEGF-treated human umbilical vein endothelial cells (HUVECs). Xanthorrhizol inhibited the phosphorylation of Akt and endothelial nitric oxide synthase (eNOS) and the expression of vascular cell adhesion molecule (VCAM)-1 and E-selectin in VEGF-treated HUVECs. The expression and transcriptional activity of NF-[Formula: see text]B were downregulated by xanthorrhizol in VEGF-treated HUVECs. Furthermore, xanthorrhizol significantly inhibited VEGF-induced angiogenesis in the chorioallantoic membrane of fertilized eggs and Matrigel plugs subcutaneously injected into mice. Xanthorrhizol inhibited tumor volume and tumor-derived angiogenesis in mice inoculated with breast cancer cells. The in vitro and in vivo anti-angiogenic activities of xanthorrhizol were as potent as those of curcumin, a well-known anticancer agent derived from C. longa. Taken together, xanthorrhizol inhibits VEGF-induced angiogenesis of endothelial cells by blocking the activation of the PI3K/Akt/eNOS axis and subsequent upregulation of adhesion molecules induced by the transcriptional activation of NF-[Formula: see text]B. Xanthorrhizol is a promising anti-angiogenic agent and can serve as a beneficial agent to enhance anticancer treatments.

Transforming growth factor-ß-regulated fractalkine as a marker of erosive bone invasion in oral squamous cell carcinoma.

Patients with oral squamous cell carcinoma (OSCC) bone invasion are surgically treated with bone resection, which results in severe physical and psychological damage. Here, we investigated the potential of fractalkine (CX3CL1), which is regulated by transforming growth factor (TGF-ß), as a novel biomarker for correct prediction and early detection of OSCC-associated bone invasion. TGF-ß knockdown and treatment with a TGF-ß-neutralizing antibody decreased the level of fractalkine in the culture media of HSC-2 and YD10B OSCC cells. Treatment with a fractalkine-neutralizing antibody reduced TGF-ß-stimulated invasion by HSC-2 and YD10B cells. Fractalkine treatment increased the viability, invasion, and uPA secretion of both OSCC cell lines. Furthermore, OSCC cell bone invasion was assessed following subcutaneous inoculation of wild-type or TGF-ß knockdown OSCC cells in mouse calvaria. TGF-ß knockdown prevented erosive bone invasion, reduced the number of osteoclasts at the tumor-bone interface, and downregulated fractalkine expression in mouse tumor tissues. Our results indicate that the production of fractalkine is stimulated by TGF-ß and mediates TGF-ß-induced cell invasion in several OSCC cell lines showing an erosive pattern of bone invasion. Fractalkine may be a useful predictive marker and therapeutic target for OSCC-induced bone destruction.

Chemerin Treatment Inhibits the Growth and Bone Invasion of Breast Cancer Cells.

Chemerin is secreted as prochemerin from various cell types and then cleaved into the bioactive isoform by specific proteases. In various cancer types, chemerin exhibits pro- or antitumor effects. In the present study, chemerin treatment significantly inhibited the viability and invasion of breast cancer cells in the absence or presence of transforming growth factor (TGF)-ß and insulin-like growth factor (IGF)-1. The expression levels of E-cadherin and vimentin were reduced in chemerin-treated breast cancer cells. However, chemerin treatment recovered the reduced E-cadherin expression level in breast cancer cells treated with TGF-ß or IGF-1. Chemerin treatment inhibited nuclear ß-catenin levels in breast cancer cells stimulated with or without TGF-ß or IGF-1. In addition, chemerin treatment blocked the increase in the receptor activator of nuclear factor kappa-Β ligand (RANKL)/osteoprotegerin (OPG) ratio in osteoblastic cells exposed to metastatic breast cancer cell-derived conditioned medium. Chemerin treatment inhibited RANKL-induced osteoclast formation and bone resorption by reducing the secretion of matrix metalloproteinase (MMP)-2, MMP-9, and cathepsin K. Intraperitoneal administration of chemerin inhibited tumor growth in MCF-7 breast cancer cell-injected mice and reduced the development of osteolytic lesions resulting from intratibial inoculation of MDA-MB-231 cells. Taken together, chemerin inhibits the growth and invasion of breast cancer cells and prevents bone loss resulting from breast cancer cells by inhibiting finally osteoclast formation and activity.

CCL28-induced RARß expression inhibits oral squamous cell carcinoma bone invasion.

Oral squamous cell carcinoma (OSCC) frequently invades the maxillary or mandibular bone, and this bone invasion is closely associated with poor prognosis and survival. Here, we show that CCL28 functions as a negative regulator of OSCC bone invasion. CCL28 inhibited invasion and epithelial-mesenchymal transition (EMT), and its inhibition of EMT was characterized by induced E-cadherin expression and reduced nuclear localization of ß-catenin in OSCC cells with detectable RUNX3 expression levels. CCL28 signaling via CCR10 increased retinoic acid receptor-ß (RARß) expression by reducing the interaction between RARα and HDAC1. In addition, CCL28 reduced RANKL production in OSCC and osteoblastic cells and blocked RANKL-induced osteoclastogenesis in osteoclast precursors. Intraperitoneally administered CCL28 inhibited tumor growth and osteolysis in mouse calvaria and tibia inoculated with OSCC cells. RARß expression was also increased in tumor tissues. In patients with OSCC, low CCL28, CCR10, and RARß expression levels were highly correlated with bone invasion. Patients with OSCC who had higher expression of CCL28, CCR10, or RARß had significantly better overall survival. These findings suggest that CCL28, CCR10, and RARß are useful markers for the prediction and treatment of OSCC bone invasion. Furthermore, CCL28 upregulation in OSCC cells or CCL28 treatment can be a therapeutic strategy for OSCC bone invasion.

Artemisinin-Daumone Hybrid Inhibits Cancer Cell-Mediated Osteolysis by Targeting Cancer Cells and Osteoclasts.

BACKGROUND/AIMS: Bone metastasis of cancer cells decreases patient survival and quality of life. Hybridization via the covalent coupling of two bioactive natural products is a useful strategy for developing more potent anticancer agents by enhancing their bioavailability and avoiding drug resistance. METHODS: The in vivo activities of artemisinin-daumone hybrid 15 (ARTD) were estimated in cancer cell-inoculated mice and ovariectomized mice. The viability, migration, and invasion of cancer cells were measured via MTT, wound-healing, and transwell invasion assays. ARTD-regulated transcription factors were detected with an RT2 profiler PCR array kit and Western blotting. Osteoclastogenesis and osteoclast activity were detected with tartrate-resistant acid phosphatase staining, a pit formation assay, gelatin zymography, and a cathepsin K ELISA assay. RESULTS: ARTD blocked cancer-associated osteolysis more potently than artemisinin in mice with intratibially inoculated breast cancer or lung cancer cells. ARTD inhibited the viability, migration, and invasion of breast and lung cancer cells in the absence or presence of transforming growth factor-ß1. ARTD treatment induced the expression of tumor suppressive activating transcription factor 3 and inhibited oncogenic E2F transcription factor 1 expression at the mRNA and protein levels. ARTD inhibited receptor activator of nuclear factor kappa-B ligand-induced osteoclast formation and bone resorbing activity by reducing the secreted levels of matrix metalloproteinase-9 and cathepsin K. Furthermore, ARTD prevented estrogen deficiency-induced bone loss in ovariectomized mice. CONCLUSION: ARTD may be a promising candidate for inhibiting cancer-induced bone destruction. The application of ARTD may be extended to patients with chemotherapy-induced ovarian failure or postmenopausal osteoporosis.

Artemisia annua extract prevents ovariectomy-induced bone loss by blocking receptor activator of nuclear factor kappa-B ligand-induced differentiation of osteoclasts.

The activities of osteoclasts and osteoblasts are balanced to maintain normal bone density. Many pathological conditions cause osteoclastic bone resorption in excess of osteoblastic bone formation, resulting in osteoporosis. We found that oral administration of Artemisia annua ethanol extract (AaE) or major components, artemisinin and arteannuin B, to ovariectomized (OVX) mice prevented bone loss, as verified by examining three-dimensional images and bone morphometric parameters derived from microcomputed tomography analysis, as well as serum levels of bone turnover markers and proinflammatory cytokines. The administered doses were not toxic to the liver or kidney and showed promising effects that were comparable to those of 17ß-estradiol treatment. At non-cytotoxic concentrations, AaE and active components, artemisinin, artemisinic acid, and arteannuin B, potently inhibited receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclastogenesis and the formation of osteoclast-mediated resorption pits. Furthermore, AaE, artemisinin, and arteannuin B remarkably reduced the expression of the c-Fos and NFATc1 transcription factors, which play critical roles in RANKL-induced osteoclast differentiation. Taken together, the in vivo anti-osteoporotic activity of AaE may be derived from the anti-osteoclastic and anti-bone resorptive activities of its active components. AaE has beneficial applications for the prevention and inhibition of osteoporosis and osteoclast-mediated bone diseases.

Human antigen R-regulated CCL20 contributes to osteolytic breast cancer bone metastasis.

Breast cancer mainly spreads to bone, causing decreased survival of patient. Human antigen R (HuR) and chemokines are important molecules associated with mRNA stability and cell-cell interaction in cancer biology. Here, HuR knockdown inhibited bone metastasis and osteolysis of metastatic breast cancer cells in mice and HuR expression promoted the metastatic ability of cancer cells via CCL20 and GM-CSF. In contrast with the findings for GM-CSF, ELAVL1 and CCL20 expressions were markedly increased in breast tumor tissues and ELAVL1 expression showed a strong positive correlation with CCL20 expression in breast cancer subtypes, particularly the basal-like subtype. Metastasis-free survival and overall survival were decreased in the breast cancer patients with high CCL20 expression. We further confirmed the role of CCL20 in breast cancer bone metastasis. Intraperitoneal administration of anti-CCL20 antibodies inhibited osteolytic breast cancer bone metastasis in mice. Treatment with CCL20 noticeably promoted cell invasion and the secretion of MMP-2/9 in the basal-like triple-negative breast cancer cell lines, not the luminal. Moreover, CCL20 elevated the receptor activator of nuclear factors kappa-B ligand/osteoprotegerin ratio in breast cancer and osteoblastic cells and mediated the crosstalk between these cells. Collectively, HuR-regulated CCL20 may be an attractive therapeutic target for breast cancer bone metastasis.

Liensinine and Nuciferine, Bioactive Components of Nelumbo nucifera, Inhibit the Growth of Breast Cancer Cells and Breast Cancer-Associated Bone Loss.

Once breast cancer cells grow aggressively and become lodged in the skeleton through migration and invasion, they interact with bone microenvironment and accelerate much more tumor growth and bone destruction. We investigated whether liensinine and nuciferine, major active components in Nelumbo nucifera (lotus), could prevent breast cancer cell-mediated bone destruction. Liensinine and nuciferine inhibited the growth of MDA-MB-231 and MCF-7 human breast cancer cells by inducing apoptosis and inhibiting proliferation via cell cycle arrest. Liensinine treatment led to the increased Bax/Bcl-2 ratio, activation of caspase-3, and subsequent cleavage of PARP. Liensinine also displayed significant inhibition on the migration and invasion of both MDA-MB-231 and MCF-7 human breast cancer cells compared with nuciferine. In addition, liensinine and nuciferine inhibited the receptor activator of nuclear factor kappa-B ligand- (RANKL-) induced osteoclast differentiation in mouse bone marrow macrophage cells and mature osteoclast-mediated bone resorption. Furthermore, oral administration of liensinine reduced the osteolysis in nude mice with intratibial injection of MDA-MB-231 cells. Collectively, liensinine and nuciferine may be promising candidates for preventing and treating breast cancer bone metastasis and the resulting osteolytic bone loss by targeting both cancer cells and osteoclasts. Liensinine has more potent anticancer and antibone resorptive activities than nuciferine.

Decursin and decursinol from Angelica gigas inhibit the lung metastasis of murine colon carcinoma.

The principal objective of the present study was to evaluate the antimetastatic activity of decursin and decursinol isolated from Angelica gigas. Decursin and decursinol inhibited the proliferation and invasion of CT-26 colon carcinoma cells. The expressions of matrix metalloproteinase (MMP)-2 and MMP-9 in cells and the activities in the culture medium were also reduced by decursin and decursinol treatment. In CT-26 cells, the extracellular signal-regulated kinase (ERK) inhibitor inhibited cell proliferation, invasion and MMP-9 expression, and the c-Jun N-terminal kinase (JNK) inhibitor suppressed the expression of both MMPs, as well as cell proliferation and cell invasion. The phosphatidylinositol-3 kinase (PI3K) inhibitor reduced only the expression of MMP-2. In addition, the invasion of CT-26 cells was inhibited by the treatment with anti-MMP-9 antibody, rather than anti-MMP-2 antibody. These results indicate that MMP-9 expression via ERK and JNK plays a critical role for the invasion of CT26 cells. Decursin and decursinol downregulated ERK and JNK phosphorylation. Moreover, oral administration of decursin and decursinol reduced the formation of tumor nodules in the lungs and the increase in lung weight caused by CT-26 metastases. Therefore, both decursin and decursinol may be beneficial antimetastatic agents, targeting MMPs and their upstream signaling molecules.

Decursin and decursinol inhibit VEGF-induced angiogenesis by blocking the activation of extracellular signal-regulated kinase and c-Jun N-terminal kinase.

The root of Angelica gigas Nakai contains two major coumarins, which have been previously identified as decursin and decursinol. Decursin has been demonstrated to exhibit potent anti-cancer activity both in vitro and in vivo. In this study, we found that decursin and decursinol at non-cytotoxic doses inhibited the VEGF-induced proliferation, migration, and capillary-tube formation of HUVECs. Moreover, decursin and decursinol suppressed microvessel formation on chorioallantoic membranes in fertilized eggs and into mouse Matrigel plugs. The oral administration of decursin and decursinol also reduced VEGF-induced angiogenesis in Matrigel. Furthermore, decursin and decursinol reduced the phosphorylation of ERK and JNK, but not p38 MAPK, in VEGF-stimulated HUVECs. Taken together, our results reveal that decursin and decursinol inhibit VEGF-induced angiogenesis by reducing the activation of ERK and JNK in HUVECs, and possess potent in vivo anti-angiogenic activity, coupled with the advantage of oral dosing. Thus, these compounds may have the potential for the treatment of cancers dependent on VEGF-induced vascularization.

Licochalcone A inhibits the growth of colon carcinoma and attenuates cisplatin-induced toxicity without a loss of chemotherapeutic efficacy in mice.

Although chemotherapy has an important function in the treatment of most solid tumours, its clinical applications are limited by severe side effects such as nephrotoxicity, hepatotoxicity, ototoxicity and neurotoxicity. Recently, a growing amount of attention has been focused on the investigation of the effects of chemopreventive agents on the inhibition of cancer cell growth and toxicity in combination with chemotherapeutics. The aim of this study was to determine whether licochalcone A (LCA) has the potential to serve as a beneficial supplement during cisplatin chemotherapy. We found that the administration of LCA alone significantly inhibited the size of the solid tumours in CT-26 cell-inoculated Balb/c mice, without any detectable induction of nephrotoxicity, hepatotoxicity and oxidative stress. LCA also suppressed cell proliferation by reducing DNA synthesis of CT-26 murine colon cancer cells in a dose-dependent manner. LCA did not affect the therapeutic efficacy of cisplatin. Furthermore, LCA inhibited the cisplatin-induced kidney damage characterized by increases in the serum creatinine and blood urea nitrogen, as well as the cisplatin-induced liver damage characterized by increases in the serum alanine aminotransferase and aspartate aminotransferase. The repeated oral administration of LCA prior to cisplatin treatment exerted a preventive effect on the cisplatin-mediated increases in the serum nitric oxide and the tissue lipid peroxidation levels, and recovered the depleted reduced glutathione levels in the tissues. These results suggest that supplementation with LCA may be beneficial in counteracting the side effects of cisplatin therapy in cancer patients.

Isoliquiritigenin inhibits tumor growth and protects the kidney and liver against chemotherapy-induced toxicity in a mouse xenograft model of colon carcinoma.

A growing amount of attention has been focused on the investigation of the effects of chemopreventive agents on the inhibition of cancer cell growth and toxicity in combination with chemotherapeutics. The objective of this study was to determine whether isoliquiritigenin (ISL) has the potential to serve as a beneficial supplement during cisplatin chemotherapy. We found that the administration of ISL alone significantly reduced the size of the solid tumors in CT-26 cell-inoculated BALB/c mice, without any detectable induction of nephrotoxicity, hepatotoxicity, and oxidative stress, and ISL reduced the viability and DNA synthesis of CT-26 murine colon cancer cells in a dose-dependent manner. ISL did not affect the therapeutic efficacy of cisplatin. Furthermore, ISL suppressed cisplatin-induced kidney damage characterized by increases in serum creatinine and blood urea nitrogen, as well as cisplatin-induced liver damage characterized by increases in serum alanine aminotransferase and aspartate aminotransferase. The repeated oral administration of ISL prior to cisplatin treatment exerted a preventive effect on cisplatin-mediated increases in serum nitric oxide and tissue lipid peroxidation levels, and it recovered depleted GSH levels in the tissues. Therefore, supplementation with ISL may be an effective approach to counteracting the side effects of cisplatin therapy in cancer patients.