Melatonin suppresses the metastatic potential of osteoblastic prostate cancers by inhibiting integrin α2 ß1 expression.

Advanced prostate cancer often develops into bone metastasis, which is characterized by aberrant bone formation with chronic pain and lower chances of survival. No treatment exists as yet for osteoblastic bone metastasis in prostate cancer. The indolamine melatonin (N-acetyl-5-methoxytryptamine) is a major regulator of the circadian rhythm. Melatonin has shown antiproliferative and antimetastatic activities but has not yet been shown to be active in osteoblastic bone lesions of prostate cancer. Our study investigations reveal that melatonin concentration-dependently decreases the migratory and invasive abilities of two osteoblastic prostate cancer cell lines by inhibiting FAK, c-Src, and NF-κB transcriptional activity via the melatonin MT1 receptor, which effectively inhibits integrin α2 ß1 expression. Melatonin therapy appears to offer therapeutic possibilities for reducing osteoblastic bone lesions in prostate cancer.

4-Acetylantroquinonol B Suppresses Prostate Cancer Growth and Angiogenesis via a VEGF/PI3K/ERK/mTOR-Dependent Signaling Pathway in Subcutaneous Xenograft and In Vivo Angiogenesis Models.

Prostate cancer is a major cause of cancer-related mortality in men in developed countries. The compound, 4-acetylantroquinonol B (4AAQB), is isolated from Antrodia cinnamomea (commonly known as Niu-Chang-Chih), which has been shown to inhibit cancer growth. However, the anticancer activity of 4AAQB has not previously been examined in prostate cancer. This study aimed to investigate the effect of 4AAQB on cancer and angiogenesis, as well as to explore its mechanism of action. Human prostate cancer cells (PC3) and human umbilical vein endothelial cells (HUVEC) were used in cell viability, cell migration, and cell cycle functional assays to evaluate the anticancer and antiangiogenic efficacy of 4AAQB in vitro. The effects of 4AAQB in vivo were determined using xenograft and angiogenesis models. The signaling events downstream of 4AAQB were also examined. The 4AAQB compound inhibited PC3 cell growth and migration, and reduced in vivo cancer growth, as shown in a subcutaneous xenograft model. Furthermore, 4AAQB inhibited HUVEC migration, tube formation, and aortic ring sprouting; it also reduced neovascularization in a Matrigel implant angiogenesis assay in vivo. The 4AAQB compound also decreased metastasis in the PC3 prostate cancer model in vivo. Serum or vascular endothelial growth factor (VEGF)-induced VEGF receptor 2 (VEGFR2), phosphoinositide 3-kinase (PI3K)/Ak strain transforming (Akt), and extracellular signal-regulated kinase ½ (ERK ½) phosphorylation were attenuated by 4AAQB in both PC3 and HUVEC. In conclusion, 4AAQB is a potential candidate for prostate cancer therapy.

Melatonin impedes prostate cancer metastasis by suppressing MMP-13 expression.

Prostate cancer has high metastatic potential. Men with higher urinary levels of the sleep hormone melatonin are much less likely to develop advanced prostate cancer compared with men with lower levels of melatonin. Melatonin has shown anticancer activity in experimental investigations. Nevertheless, the therapeutic effect of melatonin in metastatic prostate cancer has largely remained a mystery. Analyses of Gene Expression Omnibus data and human tissue samples indicated that levels of matrix metallopeptidase 13 (MMP-13) expression are higher in prostate cancer patients than in healthy cancer-free individuals. Mechanistic investigations revealed that melatonin inhibits MMP-13 expression and the migratory and invasive capacities of prostate cancer cells via the MT1 receptor and the phospholipase C, p38, and c-Jun signaling cascades. Importantly, tumor growth rate and metastasis to distant organs were suppressed by melatonin in an orthotopic prostate cancer model. This is the first demonstration showing that melatonin impedes metastasis of prostate cancer by suppressing MMP-13 expression in both in vitro and in vivo models. Thus, melatonin is promising in the management of prostate cancer metastasis and deserves to undergo clinical investigations.

Association of vitamin K with cardiovascular events and all-cause mortality: a systematic review and meta-analysis.

PURPOSE: We conducted a meta-analysis to systematically assess the prospective association between vitamin K and cardiovascular disease (CVD) events and all-cause mortality. METHODS: We searched PubMed and EMBASE through January 2019 for prospective studies that reported the association of vitamin K (assessed by dietary intake or circulating concentration) with CVD events [including total CVD, CVD mortality, total coronary heart disease (CHD), fatal CHD, nonfatal myocardial infarction (MI), and stroke] and all-cause mortality. Multivariable-adjusted hazard ratios (HRs) comparing top versus bottom tertiles of vitamin K were combined using random-effects meta-analysis. RESULTS: Twenty-one articles were included with 222,592 participants. A significant association was found between dietary phylloquinone and total CHD (pooled HR 0.92; 95% CI 0.84, 0.99; I2 = 0%; four studies), as well as menaquinone and total CHD (0.70; 95% CI 0.53, 0.93; I2 = 32.1%; two studies). No significant association was observed between dietary vitamin K and all-cause mortality, CVD mortality, or stroke. Elevated plasma desphospho-uncarboxylated MGP (dp-ucMGP), a marker of vitamin K deficiency, was associated with an increased risk of all-cause mortality (1.84; 95% CI 1.48, 2.28; I2 = 16.8%; five studies) and CVD mortality (1.96; 95% CI 1.47, 2.61; I2 = 0%; two studies). No significant association was observed between circulating total osteocalcin and all-cause mortality or total CVD. CONCLUSIONS: Our findings showed that higher dietary vitamin K consumption was associated with a moderately lower risk of CHD, and higher plasma dp-ucMGP concentration, but not total circulating osteocalcin, was associated with increased risks of all-cause and CVD mortality. However, causal relations cannot be established because of limited number of available studies, and larger prospective studies and randomized clinical trials are needed to validate the findings.

Butein inhibits metastatic behavior in mouse melanoma cells through VEGF expression and translation-dependent signaling pathway regulation.

BACKGROUND: Melanoma is an aggressive skin cancer and a predominant cause of skin cancer-related deaths. A previous study has demonstrated the ability of butein to inhibit tumor proliferation and invasion. However, the anti-metastatic mechanisms and in vivo effects of butein have not been fully elucidated. METHODS: MTT cell viability assays were used to evaluate the antitumor effects of butein in vitro. Cytotoxic effects of butein were measured by lactate dehydrogenase assay. Anti-migratory effects of butein were evaluated by two-dimensional scratch and transwell migration assays. Signaling transduction and VEGF-releasing assays were measured by Western blotting and ELISA. We also conducted an experimental analysis of the metastatic potential of tumor cells injected into the tail vein of C57BL/6 mice. RESULTS: We first demonstrated the effect of butein on cell viability at non-cytotoxic concentrations (1, 3, and 10 µM). In vitro, butein was found to inhibit the migration of B16F10 cells in a concentration-dependent manner using transwell and scratch assays. Butein had a dose-dependent effect on focal adhesion kinase, Akt, and ERK phosphorylation in B16F10 cells. Butein efficiently inhibited the mTOR/p70S6K translational inhibition machinery and decreased the production of VEGF in B16F10 cells. Furthermore, the in vivo antitumor effects of butein were demonstrated using a pulmonary metastasis model. CONCLUSION: The results of the present study indicate the potential utility of butein in the treatment of melanoma.

Varicocele is associated with varicose veins: A population-based case-control study.

OBJECTIVE: To analyze the association between patients with varicocele and varicose veins in Taiwan. METHODS: Between 2001 and 2010, comprehensive data were analyzed on the characteristics of patients with varicocele and varicose veins in Taiwan through a retrospective, nationwide, population-based study. Data were obtained from the Taiwan National Health Insurance Research Database. A total of 2727 cases with varicose veins and 10 908 randomly selected controls were included in this study. Conditional logistic regression analyses were used to examine the association between varicose veins and varicocele. RESULTS: The prevalence of varicocele was 1.3% and 0.3% for cases (with varicose veins) and controls (without varicose vein), respectively (P < 0.001). Conditional logistic regression analysis showed that the odds ratio of being previously diagnosed with varicose veins for cases was 4.71 (95% confidence interval 2.87-7.89) when compared with controls after adjusting for age, diabetes, heart disease, chronic obstructive pulmonary disease, liver and kidney disease, and edema. Furthermore, the odds ratio was 5.96 (95% confidence interval 2.90-12.24), 4.76 (95% confidence interval 1.68-13.48) and 1.69 (95% confidence interval 0.30-9.55) in patients aged <50 years, 51-65 years and >65 years, respectively. In addition, the prevalence of male infertility was 15.1% for patients with varicocele and varicose veins, and 14.5% for patients with varicocele only, but no significant difference was observed. CONCLUSION: Our findings suggest an association between both varicocele and varicose veins. In addition, this association is higher in patients aged younger than 50 years. Evaluation of male patients with varicose veins for varicocele should be recommended.

Epidemiology of Hepatocellular Carcinoma in Taiwan.

BACKGROUND: Hepatocellular carcinoma (HCC) is a major contributor to the world's cancer burden. Understanding the HCC incidence rate in Taiwan is thus an interesting avenue of research. METHODS: From an NHI database, those patients who had been newly diagnosed with HCC and who had been listed on a registry in a catastrophic illness dataset during the years 2013-2021 were enrolled in this study. Antineoplastic agent usage and comorbidities were also studied. RESULTS: The incidence rate of HCC decreased from 57.77 to 44.95 in 100,000 from 2013 to 2021. The average age of patients with HCC increased from 65.54 years old with a CCI score of 4.98 in 2013 to 67.92 years old with a CCI score of 5.49 in 2021. Among these HCC patients, the patients under antineoplastic agent treatment decreased from 53.47% to 31.41% from 2013 to 2021. The presence of comorbidities in HCC patients was about 55.77-83.01% with mild liver disease and 29.93-37.30% with diabetes (without complications) in the period 2013-2021. CONCLUSIONS: The incidence rate of HCC slightly decreased in Taiwan. Due to antineoplastic agent usage decreasing over time, these results may indicate that more early-stage HCC patients detected in recent years were mainly treated with surgeries.

Adherence to a planetary health diet, genetic susceptibility, and incident cardiovascular disease: a prospective cohort study from the UK Biobank.

BACKGROUND: The influence of adherence to a planetary health diet (PHD) proposed by the EAT-Lancet Commission on cardiovascular disease (CVD) is inconclusive. Besides, whether genetic susceptibility to CVD can modify the association of PHD with CVD remains unknown. OBJECTIVE: We aimed to investigate the association between adherence to PHD and CVD, and to evaluate the interaction between PHD and genetic predisposition to CVD. METHODS: This study included 114,165 participants who completed at least two 24-h dietary recalls and were initially free of CVD from the UK Biobank. PHD score was calculated to assess adherence to PHD. Genetic risk was evaluated using the polygenic risk score. Incidence of total CVD, ischemic heart disease (IHD), atrial fibrillation (AF), heart failure (HF), and stroke were identified via electronic health records. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: During a median follow-up of 9.9 y, 10,071 (8.8%) incident CVD cases were documented. Compared with participants with the lowest adherence to PHD, HRs (95% CIs) for total CVD, IHD, AF, HF, and stroke among those with the highest adherence were 0.79 (0.74, 0.84), 0.73 (0.67, 0.79), 0.90 (0.82, 0.99), 0.69 (0.59, 0.82), and 0.88 (0.75, 1.04), respectively. No significant interaction between the genetic risk of CVD and PHD was observed. Participants with high genetic risk and low PHD score, as compared with those with low genetic risk and high PHD score, had a 48% (95% CI: 40%, 56%) higher risk of CVD. The population-attributable risk (95% CI) of CVD for poor adherence to PHD ranged from 8.79% (5.36%, 12.51%) to 14.00% (9.00%, 18.88%). CONCLUSIONS: These findings suggest that higher adherence to PHD was associated with lower risk of total CVD, IHD, AF, and HF in populations across all genetic risk categories.

In Vivo Effect of Halicin on Methicillin-Resistant Staphylococcus aureus-Infected Caenorhabditis elegans and Its Clinical Potential.

Recently, the high proportion of methicillin-resistant Staphylococcus aureus infections worldwide has highlighted the urgent need for novel antibiotics to combat this crisis. The recent progress in computational techniques for use in health and medicine, especially artificial intelligence (AI), has created new and potential approaches to combat antibiotic-resistant bacteria, such as repurposing existing drugs, optimizing current agents, and designing novel compounds. Halicin was previously used as a diabetic medication, acting as a c-Jun N-terminal protein kinase (JNK) inhibitor, and has recently demonstrated unexpected antibacterial activity. Although previous efforts have highlighted halicin's potential as a promising antibiotic, evidence regarding its effectiveness against clinical strains remains limited, with insufficient proof of its clinical applicability. In this study, we sought to investigate the antibacterial activity of halicin against MRSA clinical strains to validate its clinical applicability, and a C. elegans model infected by MRSA was employed to evaluate the in vivo effect of halicin against MRSA. Our findings revealed the antibacterial activity of halicin against methicillin-resistant S. aureus clinical strains with MICs ranging from 2 to 4 µg/mL. Our study is also the first work to evaluate the in vivo effect of halicin against S. aureus using a C. elegans model, supporting its further development as an antibiotic.

Asiatic acid exhibits antimetastatic activity in human prostate cancer cells by modulating the MZF-1/Elk-1/Snail signaling axis.

Prostate cancer metastasis is associated with poor prognosis and is difficult to treat clinically. Numerous studies have shown that Asiatic Acid (AA) has antibacterial, anti-inflammatory, and antioxidant effects. However, the effect of AA on prostate cancer metastasis is still unclear. This purpose of this study is to investigate the effect of AA on prostate cancer metastasis and to better understand its molecular mechanisms of action. Our results indicate that AA ≤ 30 µM did not influence cell viability and cell cycle distribution in PC3, 22Rv1 and DU145 cells. AA inhibited the migratory and invasive capabilities of three prostate cancer cells to be due to its effects on Snail, but did not have activity on Slug. We observed that AA inhibited the Myeloid zinc finger 1 (MZF-1) and ETS Like-1 (Elk-1) protein interaction and affected the complex's binding capacity to the Snail promoter region, ultimately blocking Snail transcription activity. Kinase cascade analysis revealed that phosphorylation of MEK3/6 and p38MAPK was inhibited by AA treatment. Moreover, knockdown of p38MAPK enhanced AA-suppressed protein levels of MZF-1, Elk-1, and Snail, suggesting that p38MAPK influences prostate cancer cell metastasis. These results provide promise for AA as a future candidate in the development of drug therapies to prevent or treat prostate cancer metastasis.

Correction: CuI-mediated synthesis of 1-aryl-5,6,7-trimethoxybenzimidazoles as potent antitubulin agents.

[This corrects the article DOI: 10.1039/D3RA01927F.].

CuI-mediated synthesis of 1-aryl-5,6,7-trimethoxybenzimidazoles as potent antitubulin agents.

In situ CuI-mediated cyclization methodology helped yield benzimidazoles with different substitution manner, such as 1,2-diarylbenzimidazoles (4 and 5) and 1-arylbenzimidazoles (6-15). The result of structure-activity relationship (SAR) study confirmed the significance of the 5,6,7-trimethoxybenzimidazole moiety, and the representative derivatives (8-10) exhibited marked antiproliferative activity against A549, HCT-116, and PC-3 cells; in addition, they are able to inhibit the polymerization of tubulin. Among them, compound 10 inhibited the growth of A549, HCT-116, and PC-3 cells with a mean IC50 value of 0.07 µM, and its IC50 value of tubulin polymerization is 0.26 µM.

Cryptocaryone induces apoptosis in human hepatocellular carcinoma cells by inhibiting aerobic glycolysis through Akt and c-Src signaling pathways.

Hepatocellular carcinoma (HCC) is the most common form of liver cancer, with the second highest mortality rate in all cancer. Energy reprogramming is one of the hallmarks of cancer, and emerging evidence showed that targeting glycolysis is a promising strategy for HCC treatment. Cryptocaryone has been shown to display promising anti-cancer activity against numerous types of cancer. Previous study also indicated that cryptocaryone induces cytotoxicity by inhibiting glucose transport in cancer cells, but the detailed mechanism still needs to be elucidated. Therefore, this study aimed to investigate the relationship between the anti-cancer effect and glycolytic metabolism of cryptocaryone in human HCC cells. In this study, we found that cryptocaryone potently induced growth inhibition by apoptotic cell death in HCC cells. Cryptocaryone also suppressed the ATP synthesis, lactate production and glycolytic capacity of HCC cells. Mechanistic investigations showed that phosphorylation of Akt and c-Src, as well as the expression of HK1 were impeded by cryptocaryone. Moreover, cryptocaryone markedly increased the expression level of transcription factor FoxO1. Importantly, clinical database analysis confirmed the negative correlation between HK1 and FoxO1. High expression levels of HK-1 were positively correlated with poorer survival in patients with HCCs. These results suggest that cryptocaryone may promote cell apoptosis by inhibiting FoxO1-mediated aerobic glycolysis through Akt and c-Src signaling cascades in human HCC cells. This is the first study to indicate that cryptocaryone exerts anti-cancer property against human HCC cells. Cryptocaryone is a potential natural product worthy of further development into a promising candidate for HCC treatment.

Ten-years outcome analysis in patients with clinically localized prostate cancer treated by radical prostatectomy or external beam radiation therapy.

Purpose: Since there was no consensus on treatment options for localized prostate cancer, we performed a retrospective study to compare the long-term survival benefit of radiotherapy (RT) versus laparoscopic radical prostatectomy (LRP) in Taiwan. Methods: 218 patients with clinically localized prostate cancer treated between 2008 and 2017 (64 with LRP and 154 with RT) were enrolled in this study. The outcomes of RT and LRP were assessed after patients were stratified according to Gleason score, stage, and risk group. Crude survival, prostate cancer-specific survival, and metastasis-free survival were evaluated using the log-rank test. Results: The 5-year crude survival rate was 93.3% in the LRP group and 59.3% in the RT group. A significant survival benefit was found in the LRP group compared with the RT group (p = 0.004). Furthermore, significant differences were found in disease-specific survival (93.3% vs. 64.7%, p = 0.022) and metastasis-free survival (48% vs. 40.2%, p = 0.045) between the LRP and RT groups. Conclusions: Men with localized prostate cancer treated initially with LRP had a lower risk of prostate cancer-specific death and metastases compared with those treated with RT.

Chlorpromazine, an antipsychotic agent, induces G2/M phase arrest and apoptosis via regulation of the PI3K/AKT/mTOR-mediated autophagy pathways in human oral cancer.

Chlorpromazine (CPZ), an FDA-approved phenothiazine derivative used to treat schizophrenia and other psychiatric disorders, has been demonstrated to have potential anti-tumor effects. However, the potential effects of CPZ on human oral cancer cells and the underlying molecular mechanisms remain unknown. In this study, treatment of human oral cancer cells with CPZ inhibited their proliferation and induced G2/M phase arrest. Treatment with CPZ induced apoptosis through the extrinsic death receptor and the intrinsic mitochondrial pathways. In addition, the induction of autophagy was observed by the formation of autophagosomes, the expression of autophagy-related proteins and activation of the PI3K/Akt/mTOR/p70S6K pathway. The CPZ-induced cell death was reversed by the pan-caspase inhibitor Z-VAD-FMK, by the autophagy inhibitor 3-MA and by the knockdown of LC3B using a shRNA (shLC3B), suggesting that autophagy promoted CPZ-induced apoptosis. Finally, CPZ significantly suppressed tumor growth in both a zebrafish oral cancer xenotransplantation model and in a murine model of 4-nitroquinoline-1-oxide (4NQO)-induced oral cancer. Overall, this evidence demonstrated that CPZ is a novel promising strategy for the treatment of oral cancer.

Anti-inflammatory alkaloids from the root bark of Hernandia nymphaeifolia.

Four undescribed alkaloids, 7-ethoxy-6-methoxy-2-methylisoquinolin-1(2H)-one, 7,8-dihydroxy-6-methoxy-2-methylisoquinolin-1(2H)-one, N-formylhernagine, and 5,6-dihydroxy-N-methylphthalimide, were obtained from the root bark of Hernanadia nymphaeifolia, along with fourteen known compounds. The structures of these compounds were determined through spectroscopic and MS analyses. 7,8-Dihydroxy-6-methoxy-2-methylisoquinolin-1(2H)-one, N-formylhernagine, 5,6-dihydroxy-N-methylphthalimide, oxohernagine, hernandonine, and N-trans-feruloylmethoxytyramine inhibited the superoxide anion (O2-) production (IC50 values ≤ 6.23 µg/mL) by neutrophils stimulated with formyl-L-methionyl-L-leuckyl-L-phenyl-alanine/cytochalasin B (fMLP/CB). Furthermore, 7,8-dihydroxy-6-methoxy-2-methylisoquinolin-1(2H)-one, N-formylhernagine, 5,6-dihydroxy-N-methylphthalimide, oxohernagine, and N-trans-feruloylmethoxytyramine inhibited fMLP/CB-induced elastase release with IC50 values ≤ 7.41 µg/mL. In addition, 7,8-dihydroxy-6-methoxy-2-methylisoquinolin-1(2H)-one, N-formylhernagine, oxohernagine, and N-trans-feruloylmethoxytyramine showed potent inhibition with IC50 values ≤ 28.55 µM, against lipopolysaccharide (LPS)-induced nitric oxide (NO) generation.

Sphingosine-1-phosphate promotes PDGF-dependent endothelial progenitor cell angiogenesis in human chondrosarcoma cells.

The malignant bone tumors that are categorized as chondrosarcomas display a high potential for metastasis in late-stage disease. Higher-grade chondrosarcomas contain higher levels of expression of platelet-derived growth factor (PDGF) and its receptor. The phosphorylation of sphingosine by sphingosine kinase enzymes SphK1 and SphK2 generates sphingosine-1-phosphate (S1P), which inhibits human chondrosarcoma cell migration, while SphK1 overexpression suppresses lung metastasis of chondrosarcoma. We sought to determine whether S1P mediates levels of PDGF-A expression and angiogenesis in chondrosarcoma. Surprisingly, our investigations found that treatment of chondrosarcoma cells with S1P and transfecting them with SphK1 cDNA increased PDGF-A expression and induced angiogenesis of endothelial progenitor cells (EPCs). Ras, Raf, MEK, ERK and AP-1 inhibitors and their small interfering RNAs (siRNAs) inhibited S1P-induced PDGF-A expression and EPC angiogenesis. Our results indicate that S1P promotes the expression of PDGF-A in chondrosarcoma via the Ras/Raf/MEK/ERK/AP-1 signaling cascade and stimulates EPC angiogenesis.

Garcimultiflorone K inhibits angiogenesis through Akt/eNOS- and mTOR-dependent pathways in human endothelial progenitor cells.

Background Garcimultiflorone K is a novel polyprenylated polycyclic acylphloroglucinol isolated from the stems of Garcinia multiflora that exhibits promising anti-angiogenic activity in human endothelial progenitor cells (EPCs). Purpose This study sought to determine the underlying anti-angiogenic mechanisms and pharmacological properties of garcimultiflorone K. Methods We examined the anti-angiogenic effects of garcimultiflorone K and its mechanisms of action using in vitro EPC models and in vivo zebrafish embryos. Results EPCs proliferation, migration, differentiation and capillary-like tube formation were effectively and concentration-dependently inhibited by garcimultiflorone K without any signs of cytotoxicity. Our investigations revealed that garcimultiflorone K suppressed EPCs angiogenesis through Akt, mTOR, p70S6K, and eNOS signaling cascades. Notably, garcimultiflorone K dose-dependently impeded angiogenesis in zebrafish embryos. Conclusion Our data demonstrate the anti-angiogneic effects of garcimultiflorone K in both in vitro and in vivo models. Garcimultiflorone K appears to have potential in the treatment of angiogenesis-related diseases.

BMP-2 induces angiogenesis by provoking integrin α6 expression in human endothelial progenitor cells.

Bone morphogenetic protein-2 (BMP-2) is a multifunctional cytokine, capable of governing several cellular functions, including proliferation, motility, differentiation, and angiogenesis. Circulating endothelial progenitor cells (EPCs) have been shown to facilitate tissue repair, postnatal neovascularization, and tumor associated angiogenesis. Nevertheless, the impact of BMP-2 on angiogenesis of human EPCs has largely remained a mystery. In this study, we found that BMP-2 promoted cell migration and tube formation of EPCs in a concentration-dependent manner, indicating BMP-2 induced in vitro angiogenesis in human EPCs. Furthermore, BMP-2 significantly increased microvessel formation in Matrigel plug assay, and BMP-2 antagonist noggin prevented BMP-2-induced in vivo angiogenesis. Mechanistic investigations showed BMP-2 profoundly induced the expression of Id-1 and integrin α6 as well as EPCs angiogenesis by activating PI3K/Akt and MEK/ERK signaling pathways. Moreover, knockdown of Id-1 and integrin α6 by siRNA transfection obviously attenuated BMP-2-indueced tube formation of EPCs. These results suggest that BMP-2 promotes angiogenesis in human EPCs through the activation of PI3K/Akt, MEK/ERK, and Id-1/integrin α6 signaling cascades. This is the first demonstration that BMP-2 exhibits the angiogenesis property on human EPCs. BMP-2 might serve as the potential therapeutic target for treatment of angiogenesis-related diseases.