As a critical factor in the induction of angiogenesis, vascular endothelial growth factor (VEGF) has become an attractive target for anti-angiogenesis treatment. However, the side effects associated with most anti-VEGF agents limit their chronic use. Identification of naturally occurring VEGF inhibitors derived from diet is a potential alternative approach, with the advantage of known safety. To isolate natural inhibitors of VEGF, we established an in vitro tyrosine kinase assay to screen for diet-based agents that suppress VEGFR2 kinase activity. We found that a water-based extract from cinnamon (cinnamon extract, CE), one of the oldest and most popular spices, was a potent inhibitor of VEGFR2 kinase activity, directly inhibiting kinase activity of purified VEGFR2 as well as mitogen-activated protein kinase- and Stat3-mediated signaling pathway in endothelial cells. As a result, CE inhibited VEGF-induced endothelial cell proliferation, migration and tube formation in vitro, sprout formation from aortic ring ex vivo and tumor-induced blood vessel formation in vivo. Depletion of polyphenol from CE with polyvinylpyrrolidone abolished its anti-angiogenesis activity. While cinnamaldehyde, a component responsible for CE aroma, had little effect on VEGFR2 kinase activity, high-performance liquid chromatography-purified components of CE, procyanidin type A trimer (molecular weight, 864) and a tetramer (molecular weight, 1152) were found to inhibit kinase activity of purified VEGFR2 and VEGFR2 signaling, implicating procyanidin oligomers as active components in CE that inhibit angiogenesis. Our data revealed a novel activity in cinnamon and identified a natural VEGF inhibitor that could potentially be useful in cancer prevention and/or treatment.

Human mitochondrial pyrroline-5-carboxylate reductase (PYCR) is a house-keeping enzyme that catalyzes the reduction of Δ1-pyrroline-5-carboxylate to proline. This enzymatic cycle plays pivotal roles in amino acid metabolism, intracellular redox potential and mitochondrial integrity. Here, we hypothesize that PYCR1 might be a novel prognostic biomarker and therapeutic target for breast cancer. In this study, breast cancer tissue samples were obtained from Zhejiang University (ZJU set). Immunohistochemistry analysis was performed to detect the protein level of PYCR1, and Kaplan-Meier and Cox proportional analyses were employed in this outcome study. The prognostic significance and performance of PYCR1 mRNA were validated on 13 worldwide independent microarray data sets, composed of 2500 assessable breast cancer cases. Our findings revealed that both PYCR1 mRNA and protein expression were significantly associated with tumor size, grade and invasive molecular subtypes of breast cancers. Independent and pooled analyses verified that higher PYCR1 mRNA levels were significantly associated with poor survival of breast cancer patients, regardless of estrogen receptor (ER) status. For in vitro studies, inhibition of PYCR1 by small-hairpin RNA significantly reduced the growth and invasion capabilities of the cells, while enhancing the cytotoxicity of doxorubicin in breast cancer cell lines MCF-7 (ER positive) and MDA-MB-231 (ER negative). Further population study also validated that chemotherapy significantly improved survival in early-stage breast cancer patients with low PYCR1 expression levels. Therefore, PYCR1 might serve as a prognostic biomaker for either ER-positive or ER-negative breast cancer subtypes and can also be a potential target for breast cancer therapy.

Background: In addition to its essential role in ribonucleotide reduction, ribonucleotide reductase (RNR) small subunit, RRM2, has been known to play a critical role in determining tumor malignancy. Overexpression of RRM2 significantly enhances the invasive and metastatic potential of tumor. Angiogenesis is critical to tumor malignancy; it plays an essential role in tumor growth and metastasis. It is important to investigate whether the angiogenic potential of tumor is affected by RRM2.

Fibroblast growth factor (FGF) receptor (FGFR) substrate 2 (FRS2) is an adaptor protein that plays a critical role in FGFR signaling. FRS2 is located on chromosome 12q13-15 that is frequently amplified in liposarcomas. The significance of FRS2 and FGFR signaling in high-grade liposarcomas is unknown. Herein, we first comparatively examined the amplification and expression of FRS2 with CDK4 and MDM2 in dedifferentiated liposarcoma (DDLS) and undifferentiated high-grade pleomorphic sarcoma (UHGPS). Amplification and expression of the three genes were identified in 90% to 100% (9-11 of 11) of DDLS, whereas that of FRS2, CDK4, and MDM2 were observed in 55% (41 of 75), 48% (36 of 75), and 44% (33/75) of clinically diagnosed UHGPS, suggesting that these "UHGPS" may represent DDLS despite lacking histologic evidence of lipoblasts. Immunohistochemical analysis of phosphorylated FRS2 protein indicated that the FGFR/FRS2 signaling axis was generally activated in about 75% of FRS2-positive high-grade liposarcomas. Moreover, we found that FRS2 and FGFRs proteins are highly expressed and functional in three high-grade liposarcoma cell lines: FU-DDLS-1, LiSa-2, and SW872. Importantly, the FGFR selective inhibitor NVP-BGJ-398 significantly inhibited the growth of FU-DDLS-1 and LiSa-2 cells with a concomitant suppression of FGFR signal transduction. Attenuation of FRS2 protein in FU-DDLS-1 and LiSa-2 cell lines decreased the phosphorylated extracellular signal-regulated kinase 1/2 and AKT and repressed cell proliferation. These findings indicate that analysis of FRS2 in combination with CDK4 and MDM2 will more accurately characterize pathologic features of high-grade liposarcomas. Activated FGFR/FRS2 signaling may play a functional role in the development of high-grade liposarcomas, therefore, serve as a potential therapeutic target.

Background Epithelial ovarian cancer (EOC) is one of the most malignant gynecological tumors worldwide. Deregulation of long non-coding RNAs (lncRNAs) has been implicated in various oncogenic processes in multiple cancers. In this study, we aim to identify and characterize clinically relevant lncRNA deregulation in EOC. Methods LncRNAs, mRNAs and miRNAs were profiled using expression microarrays and validated using reverse transcription quantitative PCR in EOC cells and tissues. siRNAs targeting either HOXD-AS1 or PIK3R3 together with miR-186-5p inhibitors were used to modulate endogenous target expression in EOC cell lines in vitro. In vitro wound healing assay, trans-well assay, Western-blot assay,and Dual-luciferase reporter assay were used to explore the biological roles and molecular function underlying HOXD-AS1 in the EOC cells. Progression-free survival (PFS) and overall survival (OS) were statistically analyzed by Kaplan-Meier method test. Results HOXD-AS1 was found to be significantly over-expressed in EOC tumors. High HOXD-AS1 expression significantly correlated with poorer PFS and OS of EOC patients. Multivariate Cox proportional hazards modeling indicated that HOXD-AS1 was an independent risk predictor of EOC patients (HR = 1.92, p = 0.004). SiRNA inhibition of HOXD-AS1 reduced cell migration, invasion, and epithelial-mesenchymal transition (EMT) in EOC cells in vitro by preventing HOXD-AS1 directly binding to miR-186-5p, and resulting in down-regulating of PIK3R3. The novel HOXD-AS1/miR-186-5p/PIK3R3 pathway was clinically relevant as we observed a significantly inverse correlation between HOXD-AS1/miR-186-5p and between miR-186-5p/PIK3R3 in an independent cohort of 200 EOC tissues. Conclusions HOXD-AS1/miR-186-5p/PIK3R3 is a novel pathway to promote cell migration, invasion, and EMT in EOC. Electronic supplementary material The online version of this article (10.1186/s13046-019-1103-5) contains supplementary material, which is available to authorized users.

The overexpression of RRM2 [RR (ribonucleotide reductase) small subunit M2] dramatically enhances the ability of the cancer cell to proliferate and to invade. To investigate further the relevance of RRM2 and CRCs (colorectal cancers), we correlated the expression of RRM2 with the clinical outcome of CRCs. A retrospective outcome study was conducted on CRCs collected from the COH [(City of Hope) National Medical Center, 217 cases] and ZJU (Zhejiang University, 220 cases). IHC (immunohistochemistry) was employed to determine the protein expression level of RRM2, and quantitative real-time PCR was employed to validate. Multivariate logistic analysis indicated that the adjusted ORs (odds ratios) of RRM2-high for distant metastases were 2.06 [95% CI (confidence interval), 1.01–4.30] and 5.89 (95% CI, 1.51–39.13) in the COH and ZJU sets respectively. The Kaplan–Meier analysis displayed that high expression of RRM2 had a negative impact on the OS (overall survival) and PFS (progress-free survival) of CRC in both sets significantly. The multivariate Cox analysis further demonstrated that HRs (hazard ratios) of RRM2-high for OS were 1.88 (95% CI, 1.03–3.36) and 2.06 (95% CI, 1.10–4.00) in the COH and ZJU sets respectively. Stratification analysis demonstrated that the HR of RRM2 dramatically increased to 12.22 (95% CI, 1.62–258.31) in the MMR (mismatch repair) gene-deficient subgroup in the COH set. Meanwhile, a real-time study demonstrated that down-regulation of RRM2 by siRNA (small interfering RNA) could significantly and specifically reduce the cell growth and adhesion ability in HT-29 and HCT-8 cells. Therefore RRM2 is an independent prognostic factor and predicts poor survival of CRCs. It is also a potential predictor for identifying good responders to chemotherapy for CRCs.

Flap endonuclease 1 (FEN1) plays a crucial role in both DNA replication and damage repair. In this study, FEN1 expression and its clinical-pathologic significance in non-small-cell lung cancer (NSCLC) was investigated. Quantitative RT-PCR and immunohistochemistry analysis identified that both FEN1 mRNA and protein were highly overexpressed in about 36% of 136 cancer tissues compared to adjacent tissues, in which FEN1 was generally undetectable. Notably, patients with FEN1-overexpressed cancers were prone to have poor differentiation and poor prognosis. A strong positive correlation between the levels of FEN1 and Ki-67 staining was identified in these NSCLC tissues (r = 0.485), suggesting overexpressed FEN1 conferred a proliferative advantage to NSCLC. Furthermore, knockdown of FEN1 resulted in G1/S or G2/M phase cell cycle arrest and suppressed in vitro cellular proliferation in NSCLC cancer cells. Consistently, a selective FEN1 inhibitor was shown to effectively inhibit cellular proliferation of NSCLC cells in a dose-dependent manner. Additionally, knockdown of FEN1 significantly attenuated homologous DNA repair efficiency and enhanced cytotoxic effects of cisplatin in NSCLC cells. Taken together, these findings have indicated that overexpressed FEN1 represents a prognostic biomarker and potential therapeutic target for NSCLC treatment, which warrants further study.

Our results implicate baicalin and S. baicalensis in angiogenesis by inducing VEGF expression through the activation of the ERRα pathway. These data may facilitate a better understanding of the potential health benefits of these agents in the treatment of cardiovascular diseases.