TET2 mutations in Ph-negative myeloproliferative neoplasms: identification of three novel mutations and relationship with clinical and laboratory findings.

High-throughput DNA sequence analysis was used to screen for TET2 mutations in peripheral blood derived DNA from 97 patients with BCR-ABL-negative myeloproliferative neoplasms (MPNs). Overall six mutations in the coding region of the gene were identified in 7 patients with an overall mutational frequency of 7.2%. In polycythemia vera patients (n = 25) 2 mutations were identified (8%), and in those with essential thrombocythemia (n = 55) 2 mutations (3.6%); in those with unclassifiable MPN (n = 8) 3 mutations (37.5%). No primary myelofibrosis patients (n = 6) harboured TET2 mutations. Three unreported mutations were identified (p.P177fs, p.C1298del, and p.P411del), the first two in patients with unclassifiable MPN, the last in a patient with essential thrombocythemia. On multivariate analysis the diagnosis of an unclassifiable MPN was significantly related to the presence of TET2 mutations (P = 0.02; OR: 2.81; 95% CI 1.11-7.06). We conclude that TET2 mutations occur in both JAK2 V617F-positive and -negative MPNs and are more frequent in MPN-U patients. This could represent the biological link between the different classes of myeloid malignancies.

The COX-2 G/C -765 polymorphism may modulate the occurrence of cerebrovascular ischemia.

In the atherosclerotic plaque, cyclooxygenase-2 (COX-2) catalyzes prostaglandin E formation, which acts as a pro-atherogenic factor. A polymorphism, G/C -765, within the COX-2 promoter region modulates gene expression and the risk of cerebrovascular disease. We have evaluated the relation between COX-2 G/C -765 genotypes and the occurrence of cerebrovascular ischemia. We evaluated the COX-2 G/C -765 polymorphism in 110 consecutive patients with a documented history of acute ischemic cerebrovascular disease, in 110 age-matched and sex-matched subjects without such history, and in a general population (n = 324) from the same ethnical background. The frequency of the COX-2 -765C allele in patients [0.21; 95% confidence interval (CI), 0.16-0.26] was similar to those found in controls (0.28; 95% CI, 0.22-0.34) and in the general population (0.26; 95% CI, 0.23-0.29). Carriers of the CC genotype differed between patients (0.02; 95% CI, 0.00-0.05) and controls [0.10 (95% CI, 0.04-0.16), P = 0.019; odds ratio, 0.17 (95% CI, 0.04-0.79)] or the general population [0.08 (95% CI, 0.05-0.11), P = 0.023; odds ratio, 0.22 (95% CI, 0.05-0.95)]. In a multiple logistic regression analysis adjusted for confounding variables, smoking status (P < 0.001), atrial fibrillation (P = 0.004) and COX-2 G/C-765 polymorphism (P = 0.016) independently contributed to cerebrovascular ischemia, with CC carriers exhibiting a lower risk (odds ratio, 0.07; 95% CI, 0.01-0.61). Our data show an association between the COX-2 G/C-765 gene polymorphism and cerebrovascular ischemia, suggesting that the COX-2 gene is a susceptibility locus for the risk of cerebrovascular ischemic disease.