PURPOSE SARS-CoV-2 (COVID-19) is a systemic infection. Patients with cancer are immunocompromised and may be vulnerable to COVID-related morbidity and mortality. The objectives of this study were to determine if patients with cancer have worse outcomes compared with patients without cancer and to identify demographic and clinical predictors of morbidity and mortality among patients with cancer. METHODS We used data from adult patients who tested positive for COVID-19 and were admitted to two New York–Presbyterian hospitals between March 3 and May 15, 2020. Patients with cancer were matched 1:4 to controls without cancer in terms of age, sex, and number of comorbidities. Using Kaplan-Meier curves and the log-rank test, we compared morbidity (intensive care unit admission and intubation) and mortality outcomes between patients with cancer and controls. Among those with cancer, we identified demographic and clinical predictors of worse outcomes using Cox proportional hazard models. RESULTS We included 585 patients who were COVID-19 positive, of whom 117 had active malignancy, defined as those receiving cancer-directed therapy or under active surveillance within 6 months of admission. Presenting symptoms and in-hospital complications were similar between the cancer and noncancer groups. Nearly one half of patients with cancer were receiving therapy, and 45% of patients received cytotoxic or immunosuppressive treatment within 90 days of admission. There were no statistically significant differences in morbidity or mortality ( P = .894) between patients with and without cancer. CONCLUSION We observed that patients with COVID-19 and cancer had similar outcomes compared with matched patients without cancer. This finding suggests that a diagnosis of active cancer alone and recent anticancer therapy do not predict worse COVID-19 outcomes and therefore, recommendations to limit cancer-directed therapy must be considered carefully in relation to cancer-specific outcomes and death.
Factor Va, the cofactor of prothrombinase, is composed of heavy and light chains associated noncovalently in the presence of divalent metal ions. The COOH-terminal region of the heavy chain contains acidic amino acid clusters that are important for cofactor activity. In this work, we have investigated the role of amino acid region 659−663, which contains five consecutive acidic amino acid residues, by site-directed mutagenesis. We have generated factor V molecules in which all residues were mutated to either lysine (factor V5K) or alanine (factor V5A). We have also constructed a mutant molecule with this region deleted (factor VΔ659−663). The recombinant molecules along with wild-type factor V (factor VWT) were transiently expressed in mammalian cells, purified, and assessed for cofactor activity. Two-stage clotting assays revealed that the mutant molecules had reduced clotting activities compared to that of factor VaWT. Kinetic analyses of prothrombinase assembled with the mutant molecules demonstrated diminished kcat values, while the affinity of all mutant molecules for factor Xa was similar to that for factor VaWT. Gel electrophoresis analyses of plasma-derived and recombinant mutant prothrombin activation demonstrated delayed cleavage of prothrombin at both Arg320 and Arg271 by prothrombinase assembled with the mutant molecules, resulting in meizothrombin lingering throughout the activation process. These results were confirmed after analysis of the cleavage of FPR-meizothrombin. Our findings provide new insights into the structural contribution of the acidic COOH-terminal region of factor Va heavy chain to factor Xa activity within prothrombinase and demonstrate that amino acid region 659−663 from the heavy chain of the cofactor contributes to the regulation of the rate of cleavage of prothrombin by prothrombinase.
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