The translation initiation factor eIF3i up-regulates vascular endothelial growth factor A, accelerates cell proliferation, and promotes angiogenesis in embryonic development and tumorigenesis.

Vascular endothelial growth factor A (VEGFA) is a critical proangiogenic factor that is activated by hypoxia at both the transcriptional and post-transcriptional levels. In hypoxia conditions, stabilized hypoxia-inducible factor 1α (HIF1A) is the key regulator for transcriptional activation of VEGFA. However, the post-transcriptional control of VEGFA expression remains poorly understood. Here, we report that the eukaryotic translation initiation factor 3i (eIF3i) is required for VEGFA protein expression in both normal embryonic and tumorigenic angiogenesis. eIF3i is dynamically expressed in the early stages of zebrafish embryogenesis and in human hepatocellular carcinoma tissues. eIF3i homozygous mutant zebrafish embryos show severe angiogenesis defects and human hepatocellular cancer cells with depletion of eIF3i to induce less angiogenesis in tumor models. Under hypoxia, the HIF1A protein can interact with its binding sequence in the eIF3i promoter and activate eIF3i transcription. The expression of VEGFA, which should rise in hypoxia, is significantly inhibited by eIF3i siRNA treatment. Moreover, eIF3i knockdown did not cause a general translation repression but specifically reduced the translation efficiency of the VEGFA mRNAs. Taken together, our results suggest that eIF3i is induced by HIF1A under hypoxia and controls normal and tumorigenic angiogenesis through regulating VEGFA protein translation.

Distinct contributions of angiogenesis and vascular co-option during the initiation of primary microtumors and micrometastases.

Primary tumors and metastases have been thought to initiate avascularly as multicellular aggregates and later induce angiogenesis or initiate vascularly by co-opting pre-existing host blood vessels without inducing angiogenesis. These two distinct concepts of microtumor vascularization have raised significant controversies. To clarify intratumoral vascularization and tumor cell behaviors at single-cell level during the earliest stage of microtumor initiation, we established primary and metastatic microtumor models in Tg(flk1:EGFP) transgenic zebrafish. We found that tumor cells preferred to initiate avascularly as multicellular aggregates and only later (50-100 cells in size) induced angiogenesis in blood-supply-sufficient microenvironments. In blood-supply-deficient microenvironments, less tumor cells (20-30 cells per fish) managed to co-opt and migrate along host vessels, whereas more tumor cells (100-300 cells per fish) could immediately induce angiogenesis without obvious cell migration. In a metastatic model, we clearly observed that tumor cells co-opted, migrated along and proliferated on the surface of host vessels at an early stage after they extravasated from host vessels and induced angiogenesis later when micromatastases comprised only 15-30 tumor cells. Moreover, the inducement of neovessels accelerated the growth of micromatastases in size, meanwhile, decreased the migration of tumor cells on the surface of host vessels. These results suggest that vessel co-option and angiogenesis have distinct contributions during the initiation of microtumors. Microtumors initiated reasonably through co-opting host vessels or inducing angiogenesis, depending on the differences of local microenvironments and cell numbers in microtumors. The results in this study may have important implications for the therapeutic application of antiangiogenic strategies.

[Water cultured propagation of Polygonum multiflorum and dynamic changes of physiological and biochemical characteristics during adventitious roots formation].

Water cultured propagation technology of Polygonum multiflorum was investigated with Rooting Powder No. 2 (ABT 2) comparison experiments, and the dynamic changes of endogenous hormones including indole acetic acid (IAA), abscisic acid (ABA), zeatin riboside (ZRs) contents and activities of indoleacetic acid oxidase (IAAO), polyphenol oxidase (PPO) were analyzed during rooting period. The results showed that rooting percentage of softwood cutting with 50 mg x L(-1) ABT2 and 10 mg x L(-1) ABT2 + 0.2% Urea + 0.2% KH2PO4 treatments was 94%, rooting percentage of softwood cuttings of control was 46% only. The adventitious rooting displayed three distinct phases i. e. root-inducing, root formation and root-elongating phases. The dynamic changes of contents of endogenous plant hormones (IAA, ABA, ZRs) and activities of IAAO, PPO tested were tightly related to the rooting process of soft-wood cuttings in P. multiflorum. During root-inducing phase the contents of IAA, ABA and ZRs decreased sharply, whereas ZRs content and IAAO activity kept higher level. IAA content reached the peak and PPO activity increased obviously during root formation phase, while IAAO activities and ABA, ZRs contents declined to minimum. During root-elongating phase PPO, IAAO activities were higher and IAA, ABA, ZRs contents kept steady. During rooting ABT2 (50 mg x L(-1)) treatment increased the content of IAA and PPO activity in cuttings, while the opposite result occurred in contents of ZRs, ABA and IAAO activity.

Use of l-3-n-Butylphthalide within 24 h after intravenous thrombolysis for acute cerebral infarction.

OBJECTIVE: Observe the clinical efficacy of l-3-n-Butylphthalide (NBP) in acute ischemic stroke (AIS) patients within 24 h after intravenous thrombolysis using recombinant tissue plasminogen activator (hereafter termed "IT"). METHODS: One-hundred and seventy-eight patients with AIS were divided randomly into two groups: NBP and control. The former was given a NBP injection within 24 h after IT. After intravenous injection of NBP for 8-10 days, patients switched to soft capsules of NBP before or during meals. NBP treatment was continued for ≥30 days after hospital discharge. In the control group, NBP was not injected within 24 h after IT, and NBP capsules were not given after 8-10 days. Both groups were reviewed for CT or MRI 24 h after IT. The National Institutes of Health Stroke Scale (NIHSS) score was calculated. The number of patients with a modified Rankin scale (mRS) 0-2 before, 24 h, and 90 days after IT was documented. Prevalence of cerebral hemorrhage and reocclusion of blood vessels after IT was calculated. RESULTS: There were no differences in sex, age, blood pressure, blood glucose, or cerebral-infarction types between the two groups before treatment. The NIHSS score 24 h after IT and the percentage of mRS scores 0-2 were not significantly different between the two groups. Compared with the control group, the NIHSS score in the NBP group was significantly improved at 90 days, and the number of patients with a mRS score 0-2 increased significantly. There was no significant difference in hemorrhage prevalence after IT between the two groups. Prevalence of blood-vessel occlusion after IT was significantly lower in the NBP group than that in the control group. CONCLUSION: Use of NBP within 24 h after IT can reduce the prevalence of reocclusion of blood vessels without increasing the risk of cerebral hemorrhage.

A novel PEGylated liposome-encapsulated SANT75 suppresses tumor growth through inhibiting hedgehog signaling pathway.

The Hedgehog (Hh) pathway inhibitors have shown great promise in cancer therapeutics. SANT75, a novel compound we previously designed to specially inhibit the Smoothened (SMO) protein in the Hh pathway, has greater inhibitory potency than many of commonly used Hh inhibitors. However, preclinical studies of SANT75 revealed water insolubility and acute toxicity. To overcome these limitations, we developed a liposomal formulation of SANT75 and investigated its antitumor efficacy in vitro and in vivo. We encapsulated SANT75 into PEGylated liposome and the mean particle size distribution and zeta-potential (ZP) of liposomes were optimized. Using the Shh-light2 cell and Gli-GFP or Flk-GFP transgenic reporter zebrafish, we confirmed that liposome-encapsulated SANT75 inhibited Hh activity with similar potency as the original SANT75. SANT75 encapsulated into liposome exerted strong tumor growth-inhibiting effects in vitro and in vivo. In addition, the liposomal SANT75 therapy efficiently improved the survival time of tumor-bearing mice without obvious systemic toxicity. The pathological morphology and immunohistochemistry staining revealed that liposomal SANT75 induced tumor cell apoptosis, inhibited tumor angiogenesis as assessed by CD31 and down-regulated the expression of Hh target protein Gli-1 in tumor tissues. Our findings suggest that liposomal formulated SANT75 has improved solubility and bioavailability and should be further developed as a drug candidate for treating tumors with abnormally high Hh activity.