Efficacy of anticoagulants and platelet inhibitors in cancer-induced thrombosis

E-selectin inhibitor is superior to low-molecular-weight heparin for the treatment of experimental venous thrombosis

BACKGROUND

This study evaluated E-selectin inhibition with GMI-1271 (Uproleselan [GMI]) alone and in combination with the standard of care low-molecular-weight heparin (LMWH) to improve vein recanalization, decrease vein wall inflammation and protect against adverse bleeding in a primate model. We sought to examine this novel treatment of venous thrombosis.

METHODS

Using a well-documented primate animal model, iliac vein thrombosis was induced by balloon occlusion of the iliac vein for 6 hours. Starting on day 2 after thrombosis, animals began treatment in two phases. In phase one, nontreated controls received no treatment (n = 5) vs animals treated with the E-selectin inhibitor GMI, 25 mg/kg, subcutaneous (SC), once daily (n = 4) for 21 days (previously published data). In phase two, animals were treated with GMI plus a combination of LMWH 1.5 mg/kg or 40 mg (GMI + LMWHc) SC once daily (n = 8) for 19 days; and animals treated with LMWH 1.5 mg/kg or 40 mg (LMWHc) SC once daily (n = 6) for 19 days. Animals were evaluated by magnetic resonance venography for vein recanalization and inflammation by gadolinium extravasation, duplex ultrasound, coagulation tests (thromboelastography, bleeding time, prothrombin time, activated partial thromboplastin time, fibrinogen) and complete blood count at baseline, days 2, 7, 14, and 21 at euthanasia. Statistical analysis included using unpaired t test with Welch's correction for direct comparisons and one-way analysis of variance for comparison between the groups.

RESULTS

Percent vein recanalization by magnetic resonance venography was highest in the GMI alone group followed by GMI + LMWHc, both significantly different from control. On ultrasound examination, animals treated with GMI alone had no decrease in open vein lumen by day 21, whereas decreases were observed in groups GMI + LMWHc (-26%), LMWHc (-27%), and controls (-80%). Vein wall inflammation decreased significantly in all treated groups. Intimal fibrosis and intimal thickness was best preserved in the GMI alone group. An analysis of total vein wall collagen revealed a trend in all treatment groups of decreasing vein wall collagen. No clinically significant bleeding events were noted in any group. The LMWH groups trended to have prolonged coagulation test values, whereas E-selectin inhibition with GMI did not cause clinically significant changes in coagulation measures.

CONCLUSIONS

Treatment with E-selectin inhibition results in improved vein recanalization, a decrease in vein wall inflammation and vein wall intimal thickness and fibrosis, with no changes in markers of coagulation. E-selectin inhibition with GMI alone is superior to E-selectin inhibition combined with LMWH, LMWH alone, and no treatment in this deep vein thrombosis model of iliac vein thrombosis.

Comparison Between Thromboelastography and Conventional Coagulation Tests in Surgical Patients With Localized Prostate Cancer

We aimed to examine hypercoagulable and hypocoagulable conditions in patients with prostate cancer using thromboelastography (TEG) and correlate TEG parameters with conventional coagulation test. The t test was used for comparing TEG parameters and routine coagulation results. Spearman rank-order correlation was used to describe the relationship of TEG and conventional tests. Sensitivity, specificity, positive predictive values, and negative predictive values were determined for bleeding and thrombosis. Totally, 20 patients had active bleeding postoperatively, 16 of whom showed hypocoagulation on TEG test and 9 of whom showed hypocoagulation by routine coagulation test ( P = .024). Overall, 60 patients did not have active bleeding postoperatively, 51 of whom showed hypercoagulation detected by TEG test and 42 of whom showed hypercoagulation found by routine coagulation test ( P = .040). Remarkably, patients had a little higher fibrinogen (FIB) compared to controls. There was no statistical difference in any of the conventional coagulation indexes between the groups. Correlation analysis showed that reaction time (R) and coagulation time (K) were positively correlated with the prothrombin time-international normalized ratio (PT-INR) and negatively correlated with FIB ( P < .001). Contrarily, α-angle and maximum amplitude (MA) were negatively correlated with PT-INR but positively correlated with FIB. Significantly, MA showed the strongest correlation with FIB and R exhibited the strongest correlation with PT-INR. Sensitivity and specificity for bleeding and thrombosis in TEG were higher than those in conventional coagulation test. Accordingly, TEG might be superior in evaluating hypercoagulation and detecting the risk of bleeding in patients with prostate cancer.

Synthesis of gold and silver nanoparticles stabilized with glycosaminoglycans having distinctive biological activities

Metal nanoparticles have been studied for their anticoagulant and anti-inflammatory efficacy in various models. Specifically, gold and silver nanoparticles exhibit properties that make these ideal candidates for biological applications. The typical synthesis of gold and silver nanoparticles incorporates contaminants that could pose further problems. Here we demonstrate a clean method of synthesizing gold and silver nanoparticles that exhibit biological functions. These nanoparticles were prepared by reducing AuCl(4) and AgNO(3) using heparin and hyaluronan as both reducing and stabilizing agents. The particles show stability under physiological conditions and narrow size distributions for heparin particles and wider distribution for hyaluronan particles. Studies show that the heparin nanoparticles exhibit anticoagulant properties. Additionally, either gold- or silver-heparin nanoparticles exhibit local anti-inflammatory properties without any significant effect on systemic hemostasis upon administration in carrageenan-induced paw edema models. In conclusion, gold and silver nanoparticles complexed with heparin demonstrated effective anticoagulant and anti-inflammatory efficacy, having potential in various local applications.

Recent Publications on Medications and Pharmacy

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