Long non-coding RNAs (lncRNAs) have emerged as new gene regulators and prognostic markers in various cancers. Although the lncRNA nuclear enriched abundant transcript 1 (NEAT1) has been associated with tumorigenesis, its functions in renal cell carcinoma (RCC) have not been elucidated. We determined that NEAT1 is up-regulated in RCC tissue compared to corresponding non-tumor tissue. High NEAT1 expression was associated with tumor progression and poor survival in RCC patients. NEAT1 knockdown suppressed RCC cell proliferation by inhibiting cell cycle progression, and inhibited RCC cell migration and invasion by reversing the epithelial-to-mesenchymal transition phenotype. Down-regulation of NEAT1 increased the sensitivity of RCC cells to sorafenib in vitro. Mechanistic analysis revealed that NEAT1 acts as a competitive sponge for miR-34a, which prevents inhibition of c-Met. Thus, NEAT1 promotes RCC progression through the miR-34a/c-Met axis.
A series of optically active 2-hydroxytetrahydrothienopyridine derivatives were designed and synthesized as prodrugs of clopidogrel thiolactone in order to overcome clopidogrel resistance. The final compounds were evaluated for their inhibitory effect on ADP-induced platelet aggregation in rats. Compound 9a was selected for further in vitro and in vivo metabolism studies, since its potency was comparable to that of prasugrel and was much higher than that of clopidogrel. Preliminary pharmacokinetic study results showed that the bioavailability of clopidogrel thiolactone generated from 9a was 6-fold higher than that generated from clopidogrel, implying a much lower clinically effective dose for 9a in comparison with clopidogrel. In summary, 9a (vicagrel) holds great promise as a more potent and a safer antiplatelet agent that might have the following advantages over clopidogrel: (1) no drug resistance for CYP2C19 poor metabolizers; (2) lower dose-related toxicity due to a much lower effective dose; (3) faster onset of action.
Aims
We investigated the impacts of CYP2C19 polymorphisms on pharmacokinetics and pharmacodynamics of vicagrel in healthy Chinese subjects.
Methods
CYP2C19 extensive metabolizers (EMs), intermediate metabolizers (IMs) and poor metabolizers (PMs; 16 subjects/group) participated in a randomized, open‐label, 2‐period cross‐over study. Each study period lasted 7 days, with a loading dose of 24 mg of vicagrel or 300 mg of clopidogrel on day 1, and maintenance doses of 6 mg of vicagrel or 75 mg of clopidogrel daily from day 2 to day 7. The pharmacokinetics and pharmacodynamics were assessed on day 1 and day 7.
Results
After a loading dose, the AUC0‐t of the active metabolite H4 by vicagrel was slightly lower in IMs and PMs (decreased by 21 and 27%, respectively) compared to EMs. Similar results were found after maintenance doses. In EMs, the AUC0‐t of H4 by vicagrel was somewhat higher than clopidogrel after the loading dose, and comparable with clopidogrel (90% confidence interval 0.94, 1.21) after the maintenance doses. However, it was much higher than clopidogrel in PMs, with a 1.28‐fold (loading dose) and a 73% (maintenance doses) increases compared to clopidogrel (P < 0.001). Consequently, the inhibition of platelet aggregation by vicagrel was greater than clopidogrel after both loading dose (28.2 vs 12.4% at 4 hours, P < 0.01) and maintenance doses (42.8 vs 24.6% at 4 hours, P < 0.001) in PMs.
Conclusions
CYP2C19 polymorphisms have less impact on vicagrel as compared to clopidogrel. Drug exposure and response to vicagrel in PMs were even higher than to clopidogrel in IMs.
Background: Vicagrel is a novel anti-platelet drug and hydrolyzed to the same intermediate as clopidogrel via esterase, instead of CYP2C19. Here we report the first clinical trial on the tolerability, pharmacokinetics and pharmacodynamics of different doses of vicagrel, and comparison with clopidogrel in healthy Chinese volunteers.Methods: This study was conducted in two parts. Study I was a dose-escalating (5–15 mg) study. For each dose, 15 participants were randomized into three groups (total n = 45); nine participants were given vicagrel, three were given clopidogrel, and three were given a placebo. Study II was conducted to assess interactions between vicagrel and aspirin in 15 healthy participants. The plasma concentrations of the metabolites of vicagrel and clopidogrel were determined using a LC-MS/MS method. Platelet aggregation was assessed using the VerifyNow-P2Y12 assay.Results: Vicagrel (5–15 mg per day) dosing for 10 days or addition of aspirin was well tolerated in healthy volunteers. The exposure of the active metabolite increased proportionally across the dose range and was higher (~10-fold) than clopidogrel. The levels of IPA dosing 75 mg clopidogrel were between the responses of 5 mg and 10 mg vicagrel. After a single loading dose of vicagrel (30 mg) and a once-daily maintenance dose (7.5 mg) for 8 days, the maximum inhibition of platelet aggregation was similar to that seen with the combined use of vicagrel and aspirin (100 mg/day).Conclusion: Oral vicagrel demonstrated a favorable safety profile and excellent anti-platelet activity, which could be a promising P2Y12 antagonist as anti-platelet drug and can be further developed in phase II/III studies, and marketing for the unmet medical needs of cardiovascular diseases. The study was registered at http://www.chictr.org.cn (ChiCTR-IIR-16009260).
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