Recombinant human prothrombin (MEDI8111) prevents bleeding in haemophilia A and B mice.

BACKGROUND: Haemophilia A and B are treated with FVIII and FIX replacement therapy. Treatment may be complicated by inhibitory antibodies that require bypass therapy such as FEIBA(®) in which prothrombin (FII) is suggested to be the main active component. METHODS: To evaluate the effect of FII on haemophilia recombinant human (rh) FII (MEDI8111) or plasma-derived human FII (pdhFII) was given as single doses to anaesthetized haemophilia A and B mice 3 min before tail transection and rhFVIII or rhFIX was used for comparison. After tail transection, automatic bleeding registration was used to continuously measure blood loss (BL) and bleeding time (BT). Thrombin generation and plasma concentrations of human FVIII, FIX, FII and thrombin-antithrombin complex (TAT) were measured. RESULTS: Blood loss and BT were dose-dependently decreased by rhFVIII or rhFIX. The concentrations that decreased BL and BT for rhFVIII by 50% (EC50) were 0.06 and 0.01 IU mL(-1) and for rhFIX 0.07 and 0.07 IU mL(-1) , respectively. Administration of rhFVIII and rhFIX dose-dependently increased thrombin generation potential but did not affect TAT. MEDI8111 and pdhFII dose-dependently decreased BL and BT in haemophilia A mice, EC50 37 and 87 and 100 and 155 mg L(-1) respectively. In haemophilia B mice given MEDI8111 EC50 was for BL 56 mg L(-1) and for BT 67 mg L(-1) . TAT and thrombin generation increased dose-dependently for MEDI8111 and pdhFII. CONCLUSION: MEDI8111 dose-dependently decreased bleeding and increased procoagulant activity in haemophilia A and B mice and suggest that MEDI8111 may be useful for preventing bleeding in patients with haemophilia A and B.

FGF receptor genes and breast cancer susceptibility: results from the Breast Cancer Association Consortium.

BACKGROUND: Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium. METHODS: Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression. RESULTS: Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2. CONCLUSION: Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2.

Results from a large multinational clinical trial (guardian™3) using prophylactic treatment with turoctocog alfa in paediatric patients with severe haemophilia A: safety, efficacy and pharmacokinetics.

Recombinant factor VIII (rFVIII) products provide a safe and efficacious replacement therapy for prophylaxis and treatment of bleeding episodes in patients with severe haemophilia A. This multinational, open-label, non-controlled trial investigated the safety, efficacy and pharmacokinetics (PK) of turoctocog alfa, a new rFVIII product, in a paediatric population. The primary objective was to evaluate safety. A total of 31 younger children (0-5 years) and 32 older children (6-11 years), with ≥ 50 exposure days to any factor VIII (FVIII) product and no history of inhibitors, received prophylaxis with turoctocog alfa (25-50 IU kg(-1) every second day or 25-60 IU kg(-1) three times weekly). PK assessments of turoctocog alfa and the patients' previous FVIII product were performed in 28 patients. Mean exposure to turoctocog alfa was 60 exposure days per patient. This corresponds to approximately 4.5 months in the trial. None of the patients developed inhibitors (≥ 0.6 BU) and no safety concerns were raised. A total of 120 bleeding episodes (95%) were controlled with 1-2 infusions of turoctocog alfa. Based on patient reports, the success rate (defined as 'excellent' or 'good' haemostatic response) for treatment of bleeding episodes was 92%. Overall, the median annualized bleeding rate was 3.0 (interquartile range: 8.5) bleeds patient(-1) year(-1) . PK parameters were comparable between the two age groups. In conclusion, the present large global clinical trial showed that turoctocog alfa was safe, effective in treatment of bleeding episodes and had a prophylactic effect in paediatric patients.

Results from a large multinational clinical trial (guardian™1) using prophylactic treatment with turoctocog alfa in adolescent and adult patients with severe haemophilia A: safety and efficacy.

Recombinant factor VIII (rFVIII) products provide a safe and efficacious replacement therapy for prophylaxis and treatment of bleeding episodes in patients with severe haemophilia A. This multinational, open-label, non-controlled trial investigated the safety and efficacy of turoctocog alfa, a new rFVIII product. The primary objective was to evaluate safety. A total of 150 patients (24 adolescents and 126 adults) with severe haemophilia A (FVIII activity ≤ 1%), with at least 150 exposure days (EDs) to any FVIII product and no history of inhibitors were enrolled, and 146 patients (97%) completed the trial. All patients received prophylaxis with turoctocog alfa for approximately 6 months and had a mean of 85 EDs during the trial. None of the patients developed FVIII inhibitors, there were no indications of early FVIII inhibitor development and no safety concerns were identified. A total of 225 adverse events were reported in 100 (67%) patients, with the most common being events associated with dosing procedures, headaches, and nasopharyngitis. A total of 499 bleeding episodes were reported during the trial, the majority (89%) were controlled with 1-2 infusions of turoctocog alfa. Based on patient reports, the success rate (defined as 'excellent' or 'good' haemostatic response) for treatment of bleeding episodes was 81%. The overall median annualized bleeding rate was 3.7 (interquartile range: 8.7) bleeds/patient/year. In conclusion, turoctocog alfa provides a new, safe and effective alternative for prophylaxis and treatment of bleeding episodes in patients with haemophilia A.

Prevailing effectiveness of the 2009 influenza A(H1N1)pdm09 vaccine during the 2010/11 season in Sweden.

Sixty per cent of the Swedish population received the monovalent AS03-adjuvanted pandemic influenza vaccine in the autumn of 2009. We assessed the age-specific effectiveness of this pandemic vaccine against hospitalisation with laboratory-confirmed influenza A(H1N1)pdm09 during the season 2010/11, in the age group from six months to 64 years in Sweden. The screening method was applied to available surveillance data. Our results suggest a prevailing effectiveness of 72% (95% confidence interval (CI): 63­80%) with the highest effectiveness among children, six months to nine years-old (92%, 95%CI: 80­97%). However, there were limitations in data quality and study design due to the lack of systematic recording of administered vaccinations, which underline the importance of preparing for an evaluation when planning for large public health actions. Despite these limitations, we believe the results reflect true, high prevailing vaccine effectiveness. Indeed, there were fewer deaths caused by influenza and the impact of influenza on intensive care units was less severe during the 2010/11 season in Sweden than in countries with lower pandemic vaccination coverage. The association between the pandemic vaccine and narcolepsy has increased the importance of assessing the risks and benefits of the vaccination; studies on the effectiveness and the duration of protection are needed for this.

Seroreactivity for spotted fever rickettsiae and co-infections with other tick-borne agents among habitants in central and southern Sweden.

Patients seeking medical care with erythema migrans or flu-like symptoms after suspected or observed tick bite in the southeast of Sweden and previously investigated for Borrelia spp. and/or Anaplasma sp. were retrospectively examined for serological evidence of rickettsial infection (Study 1). Twenty of 206 patients had IgG and/or IgM antibodies to Rickettsia spp. equal to or higher than the cut-off titre of 1:64. Seven of these 20 patients showed seroconversion indicative of recent or current infection and 13 patients had titres compatible with past infection, of which five patients were judged as probable infection. Of 19 patients with medical records, 11 were positive for Borrelia spp. as well, and for Anaplasma sp., one was judged as positive. Five of the 19 patients had antibodies against all three pathogens. Erythema migrans or rash was observed at all combinations of seroreactivity, with symptoms including fever, muscle pain, headache and respiratory problems. The results were compared by screening an additional 159 patients (Study 2) primarily sampled for the analysis of Borrelia spp. or Mycoplasma pneumoniae. Sixteen of these patients were seroreactive for Rickettsia spp., of which five were judged as recent or current infection. Symptoms of arthritis, fever, cough and rash were predominant. In 80 blood donors without clinical symptoms, approximately 1 % were seroreactive for Rickettsia spp., interpreted as past infection. The study shows that both single and co-infections do occur, which illustrate the complexity in the clinical picture and a need for further studies to fully understand how these patients should best be treated.

Evaluation of a surveillance strategy for early detection of adenovirus by PCR of peripheral blood in hematopoietic SCT recipients: incidence and outcome.

Adenoviruses (AdV) have emerged as important causes of morbidity and mortality in patients after hematopoietic SCT (HSCT). Early diagnosis of the infection by detection of viral DNA may improve the prognosis. A surveillance strategy was evaluated for detection of AdV DNA by PCR in a prospective study of unselected allogeneic HSCT recipients. In parallel with a routine CMV surveillance program, plasma from 20 children and 77 adults was analyzed by quantitative PCR for detection of AdV DNA. In addition, in 12 unselected patients, the presence of AdV-specific T cells were analyzed by enzyme-linked immunosorbent spot (ELISPOT) at 1 to 3 months after transplantation. A total of 5 of 97 (5%) patients had detectable AdV DNA in peripheral blood. Only one patient had high titers and none developed AdV disease. BM as a source of stem cells and myelodysplastic syndrome as the indication for transplantation were independently associated with higher risk of acquiring AdV infection. AdV-specific T cells were detected in 7 (58%) of 12 patients. Although AdV DNA was found in peripheral blood by quantitative PCR in 5% of patients undergoing allogeneic HSCT, the present surveillance program did not have a significant effect on the clinical outcome.

A large-scale meta-analysis to refine colorectal cancer risk estimates associated with MUTYH variants.

BACKGROUND: defective DNA repair has a causal role in hereditary colorectal cancer (CRC). Defects in the base excision repair gene MUTYH are responsible for MUTYH-associated polyposis and CRC predisposition as an autosomal recessive trait. Numerous reports have suggested MUTYH mono-allelic variants to be low penetrance risk alleles. We report a large collaborative meta-analysis to assess and refine CRC risk estimates associated with bi-allelic and mono-allelic MUTYH variants and investigate age and sex influence on risk. METHODS: MUTYH genotype data were included from 20 565 cases and 15 524 controls. Three logistic regression models were tested: a crude model; adjusted for age and sex; adjusted for age, sex and study. RESULTS: all three models produced very similar results. MUTYH bi-allelic carriers demonstrated a 28-fold increase in risk (95% confidence interval (CI): 6.95-115). Significant bi-allelic effects were also observed for G396D and Y179C/G396D compound heterozygotes and a marginal mono-allelic effect for variant Y179C (odds ratio (OR)=1.34; 95% CI: 1.00-1.80). A pooled meta-analysis of all published and unpublished datasets submitted showed bi-allelic effects for MUTYH, G396D and Y179C (OR=10.8, 95% CI: 5.02-23.2; OR=6.47, 95% CI: 2.33-18.0; OR=3.35, 95% CI: 1.14-9.89) and marginal mono-allelic effect for variants MUTYH (OR=1.16, 95% CI: 1.00-1.34) and Y179C alone (OR=1.34, 95% CI: 1.01-1.77). CONCLUSIONS: overall, this large study refines estimates of disease risk associated with mono-allelic and bi-allelic MUTYH carriers.

Rickettsia felis infection in Sweden: report of two cases with subacute meningitis and review of the literature.

Two patients with headache and pleocytosis were diagnosed with Rickettsia felis infection using a polymerase chain reaction of cerebrospinal fluid and serological testing. Sequencing of the amplified products showed that they were 99-100% homologous to R. felis. These cases add to our knowledge of the clinical manifestations, as well as the geographical distribution, of this spotted fever agent.

Association studies on 11 published colorectal cancer risk loci.

BACKGROUND: Recently, several genome-wide association studies (GWAS) have independently found numerous loci at which common single-nucleotide polymorphisms (SNPs) modestly influence the risk of developing colorectal cancer. The aim of this study was to test 11 loci, reported to be associated with an increased or decreased risk of colorectal cancer: 8q23.3 (rs16892766), 8q24.21 (rs6983267), 9p24 (rs719725), 10p14 (rs10795668), 11q23.1 (rs3802842), 14q22.2 (rs4444235), 15q13.3 (rs4779584), 16q22.1 (rs9929218), 18q21.1 (rs4939827), 19q13.1 (rs10411210) and 20p12.3 (rs961253), in a Swedish-based cohort. METHODS: The cohort was composed of 1786 cases and 1749 controls that were genotyped and analysed statistically. Genotype-phenotype analysis, for all 11 SNPs and sex, age of onset, family history of CRC and tumour location, was performed. RESULTS: Of eleven loci, 5 showed statistically significant odds ratios similar to previously published findings: 8q23.3, 8q24.21, 10p14, 15q13.3 and 18q21.1. The remaining loci 11q23.1, 16q22.1, 19q13.1 and 20p12.3 showed weak trends but somehow similar to what was previously published. The loci 9p24 and 14q22.2 could not be confirmed. We show a higher number of risk alleles in affected individuals compared to controls. Four statistically significant genotype-phenotype associations were found; the G allele of rs6983267 was associated to older age, the G allele of rs1075668 was associated with a younger age and sporadic cases, and the T allele of rs10411210 was associated with younger age. CONCLUSIONS: Our study, using a Swedish population, supports most genetic variants published in GWAS. More studies are needed to validate the genotype-phenotype correlations.

COGENT (COlorectal cancer GENeTics): an international consortium to study the role of polymorphic variation on the risk of colorectal cancer.

It is now recognised that a part of the inherited risk of colorectal cancer (CRC) can be explained by the co-inheritance of low-penetrance genetic variants. The accumulated experience to date in identifying these variants has served to highlight difficulties in conducting statistically and methodologically rigorous studies and follow-up analyses. The COGENT (COlorectal cancer GENeTics) consortium includes 20 research groups in Europe, Australia, the Americas, China and Japan. The overarching goal of COGENT is to identify and characterise low-penetrance susceptibility variants for CRC through association-based analyses. In this study, we review the rationale for identifying low-penetrance variants for CRC and our proposed strategy for establishing COGENT.

Recommendations to improve identification of hereditary and familial colorectal cancer in Europe.

Familial colorectal cancer (CRC) accounts for 10-15% of all CRCs. In about 5% of all cases, CRC is associated with a highly penetrant dominant inherited syndrome. The most common inherited form of non-polyposis CRC is the Lynch syndrome which is responsible for about 2-4% of all cases. Surveillance of individuals at high risk for CRC prevents the development of advanced CRC. About 1 million individuals in Western Europe are at risk for Lynch syndrome. We performed a survey to evaluate the strategies currently used to identify individuals at high risk for CRC in 14 Western European countries. Questionnaires were distributed amongst members of a European collaborative group of experts that aims to improve the prognosis of families with hereditary CRC. The survey showed that in all countries obtaining a family history followed by referral to clinical genetics centres of suspected cases was the main strategy to identify familial and hereditary CRC. In five out of seven countries with a (regional or national) CRC population screening program, attention was paid in the program to the detection of familial CRC. In only one country were special campaigns organized to increase the awareness of familial CRC among the general population. In almost all countries, the family history is assessed when a patient visits a general practitioner or hospital. However, the quality of family history taking was felt to be rather poor. Microsatellite instability testing (MSI) or immunohistochemical analysis (IHC) of CRC are usually recommended as tools to select high-risk patients for genetic testing and are performed in most countries in patients suspected of Lynch syndrome. In one country, IHC was recommended in all new cases of CRC. In most countries there are no specific programs on cancer genetics in the teaching curriculum for medical doctors. In conclusion, the outcome of this survey and the discussions within an European expert group may be used to improve the strategies to identify individuals at high risk of CRC. More attention should be given to increasing the awareness of the general population of hereditary CRC. Immunohistochemical analysis or MSI-analysis of all CRCs may be an effective tool for identifying all Lynch syndrome families. The cost-effectiveness of this approach should be further evaluated. All countries with a CRC population screening program should obtain a full family history as part of patient assessment.

Minor stroke as singular manifestation of hereditary thrombotic thrombocytopenic purpura in a young man.

The authors describe a case of a 38-year-old male with minor stroke due to exacerbation of hereditary deficiency of ADAMTS 13 resulting in a chronic relapsing form of thrombotic thrombocytopenic purpura (TTP). The clue to the unusual pathogenesis was given by laboratory findings of a mild anaemia and thrombocytopenia. After two days of observation, the patient was treated with plasmapheresis resulting in normalized platelet levels and continued clinical improvement. Subsequent clinical and laboratory investigation verified the diagnosis and the patient was put on regular treatments with plasma substitution.

TGFBR1 variants TGFBR1(*)6A and Int7G24A are not associated with an increased familial colorectal cancer risk.

Variants of the transforming growth factor-beta receptor type 1 (TGFBR1) gene, TGFBR1*6A and Int7G24A, have been suggested to act as low-penetrance tumour susceptibility alleles with TGFBR1*6A being causally responsible for some cases of familial colorectal cancer (CRC). We performed a case-control study of 262 unrelated familial CRC cases; 83 hereditary non-polyposis colorectal cancer (HNPCC) and 179 non-HNPCC. Patients were genotyped for TGFBR1*6A and Int7G24A and compared with 856 controls. Further, we screened the coding region of TGFBR1 in affected members of a large family with CRC linked to 9q22.32-31.1. TGFBR1*6A allelic frequency was not significantly different in all of the familial cases compared with controls (0.107 and 0.106, respectively; P=0.915). In a subgroup analysis allele frequencies were, however, different between HNPCC and non-HNPCC familial cases (0.157 and 0.084, respectively; P=0.013). TGFBR1*6A genotype did not influence age of onset. Int7G24A allele frequencies were similar in cases and controls. No germ-line mutation was identified in the family with CRC linked to this chromosomal region. Our study provides no substantial support for the hypothesis that the polymorphic variants TGFBR1*6A or Int7G24A contribute to familial CRC risk. We cannot, however, exclude the possibility that TGFBR1 variants have a modifying effect on inherited risk per se.

Quantification of adenovirus DNA in unrelated donor hematopoietic stem cell transplant recipients.

BACKGROUND: Adenovirus (AdV) infection is a life threatening condition in immunosuppressed patients. Quantitative AdV assays can improve the clinical management of these patients. OBJECTIVES: To evaluate quantitative measurement of AdV DNA with PCR in blood from hematopoietic stem cell transplant (HSCT) recipients. STUDY DESIGN: Quantitative PCR was used to measure viral DNA levels of AdV in consecutive blood samples from 40 HSCT recipients (27 adults and 13 children) during a 1-year post-engraftment period. All patients received grafts from unrelated donors and were given anti-T-cell antibodies in the conditioning regimen. RESULTS: In the group of 40 patients, six (15%) had detectable AdV DNA in blood for different lengths of time. None of these six patients suffered from severe graft-versus-host disease. In three of the patients a high AdV viral load (>10,000 copies/mL) was detected, one of whom also had high viral load of EBV and CMV and one of EBV only. These three patients died within 2 months after detection of ADV viremia. A low AdV viral load (<500 copies/mL) was detected in three surviving patients and they did not have concomitant high viral load of neither CMV nor EBV. CONCLUSIONS: AdV viremia was present in 15% of the HSCT recipients and a high AdV viral load was associated with fatal outcome. Screening for AdV DNA with quantitative PCR in blood may be of clinical importance in allogeneic HSCT recipients in order to prevent severe clinical virological complications.

Autoimmune markers in lymphoid malignancies.

Chronic immune stimulation such as Helicobacter pylori (hp) infection, Sjögren's syndrome or coeliac disease may initiate non-Hodgkin lymphoma (NHL). The opposite (appearance of autoimmunity) has also been reported. The aim of this study was to describe the pattern of these immune markers in patients with lymphoid malignancies. Sera from 96 patients with NHL (median age 72, range 38-88, F/M 41/55) were analysed with ELISA to determine the frequency of antibodies against guinea pig (gp) and human recombinant (hr) transglutaminase type 2 (Tg2), and hr factor XIII subunit a* (part of the Tg-family), extractable nuclear antigen (ENA), and hp. As hp antibodies decrease in younger age cohorts a sex- and age-matched control group of 768 persons was used. The control population for transglutaminase antibodies consisted of 59 blood donors, (median 42 years, range 19-65) was analysed with a commercial kit. Gp-Tg2-IgG positivity was documented in 72% and hr-Tg2-IgG positivity in 15% (5% positive controls for both; P < 0.001 and ns, respectively). For IgA 3% had gp-Tg2 and 4% hr-Tg2 (5% in controls: ns for both). Anti-FXIII-IgA positivity was found in 22% (5% in controls; P = 0.03). Unspecific anti-ENA-IgG positivity was found in 24% (P < 0.001), while only 2% had specific ENA autoantibodies. Moreover, 36% were positive for anti-hp-IgG, while controls were positive in 54% (P < 0.001). The frequency of unspecific autoantibodies was increased. No differences could be noted in specific autoantibodies (hr-Tg2-IgA). In contrast, fewer than expected were anti-hp-positive. A defective immune response, similar to that in autoimmune diseases, could contribute to the pathogenesis of lymphoid malignancies.

A frame-shift mutation of PMS2 is a widespread cause of Lynch syndrome.

BACKGROUND: When compared to the other mismatch repair genes involved in Lynch syndrome, the identification of mutations within PMS2 has been limited (<2% of all identified mutations), yet the immunohistochemical analysis of tumour samples indicates that approximately 5% of Lynch syndrome cases are caused by PMS2. This disparity is primarily due to complications in the study of this gene caused by interference from pseudogene sequences. METHODS: Using a recently developed method for detecting PMS2 specific mutations, we have screened 99 patients who are likely candidates for PMS2 mutations based on immunohistochemical analysis. RESULTS: We have identified a frequently occurring frame-shift mutation (c.736_741del6ins11) in 12 ostensibly unrelated Lynch syndrome patients (20% of patients we have identified with a deleterious mutation in PMS2, n = 61). These individuals all display the rare allele (population frequency <0.05) at a single nucleotide polymorphism (SNP) in exon 11, and have been shown to possess a short common haplotype, allowing us to calculate that the mutation arose around 1625 years ago (65 generations; 95% confidence interval 22 to 120). CONCLUSION: Ancestral analysis indicates that this mutation is enriched in individuals with British and Swedish ancestry. We estimate that there are >10 000 carriers of this mutation in the USA alone. The identification of both the mutation and the common haplotype in one Swedish control sample (n = 225), along with evidence that Lynch syndrome associated cancers are rarer than expected in the probands' families, would suggest that this is a prevalent mutation with reduced penetrance.

TGFBR1(*)6A and Int7G24A variants of transforming growth factor-beta receptor 1 in Swedish familial and sporadic breast cancer.

Two common variants in transforming growth factor-beta receptor 1 (TGFBR1), TGFBR1(*)6A and Int7G24A, A allele, have been shown to act as low-penetrance tumour susceptibility alleles in several common cancers, including breast cancer. We evaluated the TGFBR1 9A/6A and Int7G24A variant frequencies in two breast cancer cohorts; a population-based cohort of breast cancer with defined family history (n=459) and in breast cancer patients from a familial cancer clinic (n=340) and in 856 controls from the Stockholm region. The familial patients from both cohorts were further divided into high- and low-risk familial breast cancer based on pedigree analysis. There was no overall association with either variant and breast cancer risk. The TGFBR1(*)6A allelic frequency was, however, higher in low-risk familial breast cancer (0.138), compared to controls (0.106; P=0.04). No significant difference was found in the high-risk familial (0.102) or sporadic cases (0.109; P=0.83 and 0.83, respectively). TGFBR1(*)6A carrier status was further associated with a high-grade sporadic breast cancer (odds ratio: 2.27; 95% confidence interval: 1.01-5.11; P=0.049). These results indicate that the TGFBR1(*)6A variant may be associated with an increased risk of low-risk familial breast cancer and might be a marker for poorly differentiated breast cancer. The Int7G24A variant was not associated with breast cancer risk or clinical presentation of the disease including prognosis in our material.