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Herein, we demonstrate that HCMV miR-UL112-5p targets ERAP1, thereby inhibiting the processing and presentation of the HCMV pp65495-503peptide to specific CTLs. In addition, we show that the rs17481334 G variant, naturally occurring in the ERAP1 3′ UTR, preserves ERAP1 from miR-UL112-5p-mediated degradation. Specifically, HCMV miR-UL112-5p binds the 3′ UTR of ERAP1 A variant, but not the 3′ UTR of ERAP1 G variant, and, accordingly, ERAP1 expression is reduced both at RNA and protein levels only in human fibroblasts homozygous for the A variant. Consistently, HCMV-infected GG fibroblasts were more efficient in trimming viral antigens and being lysed by HCMV-peptide-specific CTLs. Notably, a significantly decreased HCMV seropositivity was detected among GG individuals suffering from multiple sclerosis, a disease model in which HCMV is negatively associated with adult-onset disorder. Overall, our results identify a resistance mechanism to HCMV miR-UL112-5p-based immune evasion strategy with potential implications for individual susceptibility to infection and other diseases.

Sixty-four patients < 20 years of age, investigated for a suspicion of Philadelphia-negative myeloproliferative disease (MPD), were retrospectively evaluated to characterize the different forms and to examine the treatments used and long-term outcome. JAK2 mutations, endogenous erythroid colony growth, and clonality were investigated in 51 children. Mutations of thrombopoietin, the thrombopoietin receptor (MPL), and the erythropoietin receptor and mutations of other genes involved in the pathogenesis of MPD were investigated in JAK2 wild-type patients. Based on our criteria for childhood MPD, we identified 34 patients with sporadic thrombocythemia (ST), 16 with hereditary thrombocytosis (HT), 11 with sporadic polycythemia (SP), and 3 with hereditary polycythemia (HP). JAK2V617F mutations were present in 47.5% of ST and in no HT. The MPLS505A mutation was detected in 15/16 HT patients and in no ST (P < .00001). The JAK2V617F mutation occurred in 27% of SP patients diagnosed according to the Polycythemia Vera Study Group or World Health Organization 2001 criteria. Children with ST received more cytoreductive drugs than those with HT (P = .0006). After a median follow-up of 124 months, no patient had developed leukemia or myelofibrosis and 5% had thrombosis; the miscarriage rate in thrombocythemic patients was 14%. The low complication rate in our population suggests that children with MPD may be managed by tailored approaches.

Peripheral T‐cell lymphomas (PTCL) are usually characterized by aggressive clinical behaviour and poor clinical outcome, but their biological background has not been extensively investigated to date, due to their low incidence, about 10% of all non‐Hodgkin's lymphoma cases in Western countries, and also to the paucity of specific molecular‐genetic abnormalities. Neverthless, there is increasing biological and clinical evidence that primary nodal PTCL should be considered separately from extra‐nodal cases, but little is known about biological factors of possible clinical and prognostic impact. This immunohistochemical study has analysed the expression of p53, Mdm2, p21WAF1, BCL‐2 and p‐glycoprotein (MDR‐1 gene product) in a series of 45 cases of nodal peripheral T‐cell lymphomas (PTCL) with ‘high‐grade’ histology. The immunohistochemical findings were then correlated with proliferative activity and clinical outcome. p53 was over‐expressed in 13 cases (28.9%). p53 positive cases showed significantly higher proliferative activity (p<0.01), more frequent expression of Bcl‐2 (p<0.01) and less frequent expression of p21WAF1than p53 negative cases. Mdm2 and p‐glycoprotein were expressed in 4/13 (30.8%) and 8/13 (61.5%) p53 positive cases respectively, and in none (0%) of the p53 negative cases (p<0.01). Analysis of the survival curves showed that p53 positive cases were associated with a significantly poorer clinical outcome than p53 negative cases, in terms of both overall survival (p=0.0032) and event‐free survival (p=0.0004). Furthermore, multivariate analysis showed that p53 expression was the most important independent prognostic variable. These findings indicate that p53 over‐expression identifies a subset of nodal PTCL cases with a distinctive biological profile (higher proliferative activity, less frequent expression of p21WAF1and more frequent expression of Bcl‐2, Mdm2 and p‐glycoprotein than p53 negative cases) and poor clinical outcome. The immunohistochemical analysis of p53 expression is a simple, rapid and low‐cost method which may provide information of potential clinical and prognostic value in nodal peripheral T‐cell lymphomas. Copyright © 2001 John Wiley & Sons, Ltd.

The expression of p53 and the retinoblastoma gene has been investigated by immunohistochemical and molecular analysis in 45 cases of nodal peripheral T-cell lymphoma with high-grade histology. Most cases (73·3 per cent) were primary nodal lymphomas without any extra-nodal site involvement. Most of them (75·6 per cent) were histologically classified as pleomorphic, small, medium, and large cell type. Immunohistochemistry detected p53 in nine cases (20 per cent). In each of these cases, the polymerase chain reaction (PCR)/heteroduplex analysis did not show the presence of mutations, this finding being consistent with an alteration of the p53 functional pathway, in the presence of a wild-type protein. The retinoblastoma gene product was detected by immunohistochemistry in 35 cases (77·8 per cent) and not detected in ten cases (22·2 per cent). In the latter cases, the reverse transcription (RT)-PCR analysis showed the presence of a specific retinoblastoma gene transcript in six cases and was negative in the remaining four cases. The immunohistochemical and molecular findings seem to be consistent with abnormalities of retinoblastoma gene expression at either the transcriptional or the post-transcriptional level. Since all nine p53-positive cases by immunohistochemical analysis were also retinoblastoma gene product-positive, and all ten retinoblastoma gene product-negative cases were also p53-negative, two different and mutually exclusive pathways of possible pathogenetic significance may be suggested, the former involving abormalities of the functional pathway of p53 in the absence of mutations and the latter abnormalities of retinoblastoma gene expression at the transcriptional and/or post-transcriptional level. Finally, the clinico-pathological correlations showed that p53 immunohistochemical expression is significantly associated with a poorer response to intensive chemotherapy. Copyright © 1999 John Wiley & Sons, Ltd.

Several associated thrombophilic abnormalities have been reported in adults with Bcr-Abl negative chronic myeloproliferative disorders (MPD), mostly essential thrombocythemia (ET) and polycythemia vera (PV), but sporadic data are available in younger patients (pts). In order to define coagulation abnormalities in very young pts, we evaluated thrombophilic parameters in MPD pts aged <20 years (yrs) at diagnosis. Prothrombin time (PT), activated partial thromboplastin time (aPTT), lupus anticoagulant (KCT and dRVVT), functional protein C (PC), free protein S (PS) antigen, functional antithrombin (AT), homocysteine (HCY), factor V Leiden (FVL) mutation, factor II (FII) G20210A mutation and methylentethrahydrofolate reductase (MTHFR) C677T polymorphism were investigated. Thirty-two MPD pts (16 males and 16 females) with a median age of 166/12 yrs (range: 3mo-1911/12 yrs) diagnosed at the study Institution between March 1980 and February 2005 were tested after informed consent of pts or parents. Twenty-five had a diagnosis of ET (7 familial forms) and 5 had PV, according to the criteria of the PV Study Group; in 2, a diagnosis of MPD with thrombocytosis and erythrocytosis was made. Cytogenetic and molecular studies were normal in all cases. At diagnosis, median platelet count for ET and MPD pts was 1,184 x 109/L (range 611–2,640); median hematocrit level for PV and MPD pts was 54% (range 52–72%). Among the ET cohort, 6 asymptomatic pts received no treatment, 4 were treated with aspirin alone and 15 received cytoreductive therapy. PV and MPD pts were phlebotomized to maintain a hematocrit level <50%. Median interval between diagnosis and the time of the study was 8.8 yrs (range: 1 mo – 24 yrs ). No thrombotic events occurred. Four female ET became pregnant and had 4 children, 1 of them being affected by familial thrombocythemia. At the time of the coagulation study, median platelet count for ET and MPD pts was 695 x 109/L (range 325–1,120); the median hematocrit level for those with PV and MPD was 53% (range 52–60.5%). Increased PT and aPTT ratios (n.v. <1.14 and <1.16) were observed in 8/32 (20%) and 16/32 (50%) pts, combined in 7. KCT ratio (n.v. <1.31) was increased in 4/31 (13%) pts, while the dRVVT ratio was normal in 31/31 tested pts. Functional PC and free PS levels were decreased in 3/30 (10%) and 3/31 (10%) tested pts, respectively. AT levels were normal in all pts (32/32). An increased HCY level was found in 1 PV pt. Of the 27 pts investigated for FVL, FII G20210A mutations and MTHFR C677T polymorphism, 1 ET pt was heterozygous for both the FVL and FII G20210A mutations, 1 ET pt was heterozygous for both MTHFR C677T polymorphism and FII G20210A mutation. One ET pt showed an isolated FII G20210A mutation. Screening for the C677T polymorphism in the MTHFR gene revealed that 18 pts (66.5%) were heterozygous, 15 of them affected by ET (7 with the familial form). In our MPD population of children and young adults, the frequencies of heterozygosis of FII G20210A mutation (3/27 pts = 11%) and MTHFR C677T polymorphism (66.5%) were higher than those reported in the normal population (about 2.5% and 45%, respectively). Larger multicenter studies are required to further extend these observations.