MiR-124 and miR-506 are involved in the decline of protein C in children with extra-hepatic portal vein obstruction.

The deficiency of protein C (PROC) can be partly rescued by Rex shunt through restoring portal blood flow in children with extra-hepatic portal venous obstruction (EHPVO). However, the decline of PROC is still found in some patients with a normal portal blood flow after Rex shunt. The aim of this study was to identify the candidate miRNAs involving in the decline of PROC and their mechanism. The protein level of PROC was detected by the ELISA assay, and was compared between sick and healthy groups. The expressions of miRNAs and PROC mRNA were measured using qRT-PCR, and were compared between sick and healthy groups. The correlation between PROC and candidate miRNAs was analysed by a Pearson correlation analysis to identify the most significant miRNAs. The expression of PROC mRNA was detected by qRT-PCR in HL-7702 and LX-2 cells tansfected with miRNAs mimics or inhibitors and negative control (NC) mimics, which was compared among the different groups. The rates of liver cells' proliferation and apoptosis were detected in HL-7702 and LX-2 cells tansfected with miRNAs mimics or inhibitors or with overexpressing PROC and negative control mimics by CKK8 assay and flow cytometry, which were compared among the different groups. The expressions of COX-2 and VEGF were measured by qRT-PCR, and were compared between the miRNAs groups and NC group. Western blot was assayed for detecting the protein levels of PROC, COX-2, VEGF, Bcl-2 and Bax, which were compared between the miRNAs groups and NC group. The expression of PROC mRNA was lower, and the expressions of miR-506-3p and miR-124-3p were higher in children with EHPVO than healthy group. PROC mRNA was negatively correlated with the expression of miR-506-3p and miR-124-3p. Compared to the NC group, the transcription activity of PROC was lower after exposure of miR-506 and miR-124 mimics in HL-7702 and LX-2 cells, but this phenomenon was reversed after inhibiting miR-506 and miR-124. The rate of cell proliferation was lower after exposure of miR-506 and miR-124 than the NC group, which was increased after inhibiting miR-506 and miR-124 in HL-7702 cells and overexpressing PROC in LX-2 cells. The apoptotic rate was higher after exposure of miR-506 and miR-124 than the NC group, which was decreased after inhibiting miR-506 and miR-124 in HL-7702 cells and overexpressing PROC in LX-2 cells. The mRNA levels of COX-2 and VEGF were significantly higher after exposure of miR-506 and miR-124 mimics than those in the NC group. The protein levels of PROC and Bcl-2 were down-regulated, and the levels of COX-2, Bax and VEGF were up-regulated after exposure of miR-506 and miR-124 in HL-7702 cells, but this phenomenon was reversed after inhibiting miR-506 and miR-124. MiR-506-3p and miR-124-3p may involve in the decline of PROC in protein and transcriptional level, in which the anti-proliferation and pro-apoptosis role of miR-506-3p and miR-124-3p for liver cells may involve in this mechanism.

Severe Protein C Deficiency due to Novel Biallelic Variants in PROC and Their Phenotype Correlation.

Severe protein C deficiency due to biallelic PROC mutations is an extremely rare thrombophilia, most commonly presenting during the neonatal period as purpura fulminans. Despite treatment, severe morbidity and mortality are frequent. The current study reports 3 unrelated patients harboring novel homozygous PROC mutations and their clinical phenotypes. We discuss how the cytoprotective activity of protein C and its role in the stabilization of endothelial barriers may account for the unique symptoms of this thrombophilia.

Thrombophilia testing in patients with portal vein thrombosis.

Portal vein thrombosis (PVT) is a rare but severe condition. Several risk factors predispose to PVT. However, it remains unclear to which degree thrombophilia contributes to the risk of PVT and whether PVT patients should be routinely referred for thrombophilia testing. The aim of the present study was to investigate the prevalence of thrombophilia in PVT patients to clarify the relevance of thrombophilia testing in PVT patients. Clinical data and results from thrombophilia investigations were systematically obtained from all PVT patients referred to Centre for Hemophilia and Thrombosis, Aarhus University Hospital, Denmark for thrombophilia testing between 1st of January 2010 and 31st of December 2018 (n = 93). The investigated thrombophilias included factor V Leiden and prothrombin G20210A mutations, deficiency of protein S, protein C and antithrombin, antiphospholipid syndrome, and increased levels of factor VIII. The prevalence of thrombophilia was compared to healthy controls obtained from previously published data on thrombophilia distribution in cohorts of the Western European adult general population. Comparing PVT patients with healthy controls, significantly increased odds of presence of lupus anticoagulant (crude odds ratio (OR) 6.2, 95% confidence interval (CI) 1.8-20.6) were found, whereas no significantly increased odds of inherited thrombophilia were demonstrated. In conclusion, routine testing for inherited thrombophilia in PVT patients does not seem indicated. However, PVT patients should still be tested for antiphospholipid antibodies because patients meeting the criteria for antiphospholipid syndrome preferentially should receive vitamin K antagonists as anticoagulant therapy.

Management of severe congenital protein C deficiency with a direct oral anticoagulant, edoxaban: A case report.

A male patient diagnosed with severe congenital protein C (PC) deficiency during the neonatal period was treated with long-term warfarin but frequently developed purpura fulminans and bleeding. At four years of age, edoxaban was initiated (direct oral anticoagulant [DOAC]). His d-dimer and fibrin/fibrinogen degradation product levels were closely monitored. His PC activity increased from below the sensitivity range to 17%; this increase was thought to be due to a reduction in PC consumption during edoxaban therapy. After edoxaban introduction, he experienced just one episode of purpura fulminans over two years without any adverse events. Thus, DOAC may be a promising alternative for the management of congenital PC deficiency.

Cerebral Sinus Venous Thrombosis and Prothrombotic Risk Factors in Children: A Single-Center Experience From Turkey.

BACKGROUND: Cerebral sinus venous thrombosis (CSVT) is a rare cerebrovascular disease that may be life-threatening, especially in children. OBJECTIVE: The purpose of this study was to assess the clinical presentation, radiologic imaging, underlying conditions, treatment, and outcomes of children with CSVT. PATIENTS AND METHODS: In total, 23 consecutive children aged between 1 month to 18 years with CSVT, who were followed-up in Erciyes University Children's Hospital, were retrospectively enrolled in the study from January 2000 to December 2016. RESULTS: The median age of the 23 children (13 female patients, 10 male patients) at initial diagnosis was 60 months (1 to 204 mo). The most common clinical manifestation was headache/irritability (n=9). The most common site of the CSVT was the transverse sinus (n=16). The most common prothrombotic risk factor was protein C deficiency (n=4). Underlying risk factors were detected in 15 patients. Genetic risk factors such as protein C deficiency, infections, trauma, malignancies, autoimmune hemolytic anemia, neurometabolic disorders, asphyxia, and cardiac malformations were common risk factors. Six children died. Multiple sinus involvement and parenchymal hemorrhages were seen in 4 and in 3 of the 6 children who died, respectively. CONCLUSIONS: Protein C deficiency seemed to be relatively high in the presented children. Multiple sinus involvement and additional parenchymal hemorrhages represent poor prognostic features.

Severe Congenital Protein C Deficiency: Practical Aspects of Management.

Subcutaneous (SC) protein C (PC) was used in a child with purpura fulminans secondary to severe congenital PC deficiency. For maintenance, PC 80-120 IU/kg, given over 60-90 min SC Q48hr, has been successful as a home therapy for more than 3 years. The treatment was monitored by measuring trough PC chromogenic activity (target ≥15%) and D-dimer levels. No change in clinical course was appreciated after discontinuing enoxaparin (and leaving the patient on prophylactic PC replacement alone). A significant discrepancy between clotting-based and chromogenic-based PC activity is shown.

Sagittal vein thrombosis caused by central vein catheter.

Cerebral venous thrombosis, including thrombosis of cerebral veins and major dural sinuses, is an uncommon disorder in the general population. However, it has a higher frequency among patients younger than 40 years of age, patients with thrombophilia, pregnant patients or those receiving hormonal contraceptive therapy or has foreign body such as catheter in their veins or arterial system. In this case report, we described clinical and radiological findings in a patient with protein C-S deficiency and malposition of central vein catheter.

Different impact of two mutations of a novel compound heterozygous protein C deficiency with late onset thrombosis.

We investigated the alteration of coagulation state in a protein C (PC) deficiency pedigree and the impact of the PC gene mutations. The pedigree of a proband with cerebral hemorrhagic infarction had sixteen members with four generations. The plasma levels of PC activity (PC:A), protein S activity (PS:A), factor V:C and factor VIII:C, and routine coagulation tests were measured. Nine exons of the PC gene (PROC) were sequenced. Plasma PC:A and PC antigen (PC:Ag) of the proband were 26 and 18%, respectively, which was significantly lower than normal ranges. Two heterozygous missense mutations of PC in the proband were identified, T>G at site 6128 (exon 7) and G>C at site 8478 (exon 9) resulting in F139V and D255H, respectively. The family members with F139V (N = 4) or D255H (N = 4) had lower levels of PC:A and PC:Ag than members with wild-type PROC (N = 6). D255H mutation caused a more significant decrease in the levels of PC:A, PC:Ag and factor V:C as compared to F139V mutation (P < 0.05). Two independent mutations, F139V and D255H, of PROC reduce PC function. Compound heterozygous condition of the two mutations can cause synergistic PC deficiency, but resulting in later onset of cerebral thrombosis.

Paediatric presentation and outcome of congenital protein C deficiency in Japan.

Severe heritable protein C (PC) deficiency is quite rare, although heterozygous PROC mutation is the second leading cause of genetic predisposition to thrombosis in Japanese adults. The aim of the study was to search the optimal management, the paediatric onset and outcomes of PC deficiency were characterized in Japan. The genetic study, postmarketing survey of activated PC(aPC) concentrate (Anact(®)C) and intensive review in Japan for 20 years enabled the analysis of the disease onset, genotype, treatment and prognosis. Symptomatic PC deficiency was determined in 27 Japanese children. All but two patients presented within 16 days after birth (three prenatal and six neonatal onsets). Postnatal-onset cases had normal growth at full-term delivery. Of the 27 patients, 19 suffered intracranial thrombosis or haemorrhage (ICTH) (three foetal hydrocephalies), 16 developed purpura fulminans (PF) and 10 had both at the first presentation. ICTH preceded PF in both affected cases. Low PC activities of 18 mothers and/or 12 fathers indicated 20 inherited PC deficiencies (2 homozygotes, 11 compound heterozygotes and 7 heterozygotes) and seven unidentified causes of PC deficiency. Nine of 11 patients studied had PROC mutations. Four unrelated patients (50%) carried PC nagoya (1362delG). No PC-deficient parents had experienced thromboembolism. Of the 18 patients with aPC therapy, two died and eight evaluable survivors had neurological sequelae. This first comprehensive study of paediatric PC deficiency suggested that perinatal ICTH was the major presentation, occurring earlier than neonatal PF. PC nagoya was prevalent in paediatric, but not adult, patients in Japan. Early maternal screening and optimal PC therapy are required for newborns at risk of PC deficiency.

Homozygous protein C deficiency with late onset venous thrombosis: identification and in vitro expression study of a novel Pro275Ser mutation.

AIMS: To identify the mutation and study the molecular mechanism of inherited protein C (PC) deficiency in a Chinese pedigree. METHODS: The plasma levels of PC activity (PC:A) and antigen (PC:Ag) were measured by chromogenic assay and ELISA, respectively. The PROC gene was amplified and sequenced for mutational screening. Wild type and Pro275Ser mutant PC cDNA expression plasmids were constructed and transfected into HEK 293T cells and COS 7 cells, respectively. The expression and transcription of PC were investigated by ELISA, Western blot and real time RT-PCR. Immunofluorescence staining was utilised to analyse the intracellular distribution of PC, and pulse-chase experiments were used to detect the intracellular stability of the mutant PC. RESULTS: The proband's plasma PC:A and PC:Ag were 5% and 13.9%, respectively. A missense mutation (p.Pro275Ser) was identified in exon 9 of PROC gene. In vitro expression study showed that Pro275Ser variant was present at 22.6% and 78.9% of wild type levels in culture supernatants and cell lysates, respectively. No significant differences in the molecular weights, mRNA levels or intracellular stability were observed between the mutant and wild type PC. Immunofluorescence staining revealed that the mutant protein was mainly located in the endoplasmic reticulum. CONCLUSIONS: A homozygous Pro275Ser mutation was identified in a Chinese pedigree of PC deficiency. Impaired secretion of the mutant PC might be the molecular mechanism of PC deficiency caused by Pro275Ser mutation.

Thrombophilic disorders: a real threat to patients with end-stage renal disease on hemodialysis and at the time of renal transplantation.

Management of end-stage renal disease is the mainstay of prevention of renal vascular complications and kidney rejection. We sought to describe the association of some disorders such as diabetic nephropathy, polycystic renal disease, hypertension, and thrombophilia with renal failure and discuss possible mechanisms explaining the implication of the thrombophilic states in kidney allograft thrombosis and renal rejection. Five hundred and sixty-eight patients were included in this case-control study and multivariate analysis was applied. Cases and controls were tested for all major types of thrombophilia. Diabetic nephropathy, autosomal dominant polycystic kidney disease, hypertension, and smoking are the strongest causal agents of end-stage renal disease in Tunisia. It should also be noted that the prevalence of factor V Leiden (P = 0.05) and protein C deficiency (P = 0.005) were significantly higher in ESRD patients awaiting renal transplantation than controls. The present study has raised the possibility that thrombophilic factors may play a pathophysiological role in renal failure. These results will serve as a basis for anticoagulant prophylaxis aimed at preventing kidney rejection and renal allograft thrombosis.

Acroangiodermatitis of Mali in protein C deficiency due to a novel PROC gene mutation.

Acroangiodermatitis of Mali is a dermatologic condition of kaposiform skin lesions that has been associated with chronic venous insufficiency. Here we report a case of a 28-year-old Chinese man with acroangiodermatitis which co-existed with chronic lower limb deep vein thrombosis. Investigations revealed protein C deficiency and a frame shift mutation, c246_247dupCT, of the PROC gene. Our report lengthens the list of male acroangiodermatitis of Mali cases with a Chinese patient harboring a novel PROC mutation with manifest protein C deficiency.

[Skin necrosis during long-term fluindione treatment revealing protein C deficiency]. / Nécroses cutanées tardives sous fluindione révélant un déficit en protéine C.

BACKGROUND: Cutaneous necrosis is a rare complication of vitamin K antagonist therapy. It presents as cutaneous hemorrhagic necrosis and usually occurs at the start of treatment. We describe an atypical case of recurrent skin necrosis after two years of treatment with fluindione. CASE REPORT: A 70-year old woman with a history of venous thromboembolism and obesity presented with a large haemorrhagic necrosis of the abdominal wall. She had been treated with fluindione for two years. Genetic protein C deficiency was discovered. Resumption of vitamin K antagonist therapy was followed by recurrence of skin necrosis despite concomitant administration of heparin. Treatment with vitamin K antagonists could not be continued. DISCUSSION: This observation is unusual due to the late onset of skin necrosis. The condition usually begins shortly after initiation of vitamin K antagonist therapy, generally between the third and the sixth day of treatment. It is due to a transient hypercoagulable state in patients with protein C deficiency or, in rare cases, protein S deficiency. This late-onset skin necrosis, occurring many years after initiation of anticoagulant therapy, may be explained by a sudden worsening of pre-existing protein C deficiency due to infectious and iatrogenic factors.

[A pedigree analysis of pulmonary embolism caused by compound heterozygous mutations of protein C].

OBJECTIVE: To study the molecular pathogenesis of protein C (PC) deficiency in a patient with pulmonary embolism and in his family members. METHODS: Anticoagulated blood samples were collected from the proband and his family members to detect PC, PS and AT activities. PC antigen level was measured using ELISA. The genomic DNA was extracted to amplify all the 9 exons and their flanking sequences of PC gene using PCR, and the PCR products were sequenced. The mutated exons identified were amplified and sequenced for the other family members. RESULTS: The proband and his parents and sister were identified as carriers of PC gene mutation, which led to type II PC deficiency. Sequencing of the proband's PC gene showed two heterozygous point mutations in exon 3 (G5540A) and exon 7 (C10230T) to cause compound heterozygous mutations of PC E29K and PC R147W, which were inherited from his father and mother, respectively. His sister was a heterozygote of PC R147W. CONCLUSION: The proband is a compourd heterozygous mutations carrier of PC E29K and PC147W. PC E29K is a novel PC mutation, and PC R147W is a reported PC gene mutation seen in patients with type II hereditary PC deficiency and recurrent thrombosis.

Freiburg neuropathology case conference: a midline mass lesion in an infant.

This article presents the case of a 10-month-old baby girl with an atypical teratoid/rhabdoid tumor. The differential diagnosis relied on the findings from magnetic resonance with T1 and T2-weighted imaging as well as histological and immunohistochemical methods. The characteristics of the possible candidate lesions considered for the differential diagnosis are described.

Testing for inherited thrombophilias in arterial stroke: can it cause more harm than good?

BACKGROUND AND PURPOSE: Despite a paucity of evidence supporting a true association of ischemic stroke and the inherited thrombophilias, it is common practice for many neurologists to order these tests as part of the work-up of ischemic stroke, especially in young patients. Treatment with oral anticoagulation is often used in patients with positive results for the inherited thrombophilias. METHODS: We reviewed the literature focusing on case-control studies of the 5 most commonly inherited disorders of coagulation: protein C deficiency, protein S deficiency, antithrombin deficiency, and the factor V Leiden and prothrombin gene mutations in patients with stroke. We also analyzed the available data on stroke patients with inherited thrombophilia and patent foramen ovale. RESULTS: Multiple case-control studies have not convincingly shown an association of the inherited thrombophilias with ischemic stroke, even in young patients and patients with patent foramen ovale. CONCLUSIONS: If there is an association between the inherited thrombophilias and arterial stroke, then it is a weak one, likely enhanced by other prothrombotic risk factors. The consequences of ordering these tests and attributing causality to an arterial event can result in significant costs to the health care system and pose a potential risk to patients, because this may lead to inappropriate use of long-term oral anticoagulants, exposing patients to harm without a clearly defined benefit.

[Thyroid crisis and protein C deficiency in a case of superior sagittal sinus thrombosis].

We report the case of a 28-year-old woman who presented simultaneously with superior sagittal sinus thrombosis and thyroid crisis, and was subsequently found to have protein C deficiency. February 3, 2003, she admitted complaining of abdominal pain. The diagnosis of appendicitis was made, and she was operated on under lumbar anaesthesia. Day 7, she developed acute headache and distal weakness of the left lower limb. On examination she was alert, with a temperature of 38 degrees C, a sinus tachycardia of 124/min and blood pressure 164/84 mmHg. Neurological examination revealed neck stiffness and left hemiparesis, predominantly in her lower limb. Gadlinium-enhanced brain MRI revealed extensive superior sagittal sinus thrombosis. CT scan demonstrated infarction in the right frontal cortex, and subarachnoid hemorrhage adjacent to the right cerebellar tentorium. The patient was treated with a free radical scavenger edarabon, and glycerin. No anticoagulant therapy was instituted. Over the next 24 hours, her condition worsened. She became comatose, as well as developing a generalized tonic-clonic seizure. Day 12, laboratory examinations revealed an undetectable TSH-level CTSH (thyroid stimulating hormone) <0.005 mcIU/ml), with a level of free thyroxin 7.77 ng/dl (0.9-1.7), free triiodothyronin 29.6 pg/ml (2.3-4.3), and positive anti-TSH receptor antibodies determined subsequently. Coagulation factor VIII activity was 155% (normal range 60-150). Protein C deficiency (antigen 59%, activity 49%) was also present, suggesting a congenital type I heterozygous deficiency. A diagnosis of thyroid crisis on the basis of Graves' disease was made. The patient remained comatose and died on Day 16, with renal failure. The patient had protein C deficiency, a well-established risk factor for cerebral venous thrombosis (CVT). However, additional risk factors are required in most cases to precipitate CVT. In our case, this trigger was most likely thyroid crisis, suggesting that thyrotoxicosis, probably through hypercoagulability, may be a predisposing factor for the development of CVT.

Acute inflammation is exacerbated in mice genetically predisposed to a severe protein C deficiency.

The anticoagulant, activated protein C (aPC), possesses antithrombotic, profibrinolytic, anti-inflammatory, and antiapoptotic properties, and the level of this protein is an important marker of acute inflammatory responses. Although infusion of aPC improves survival in a subset of patients with severe sepsis, evidence as to how aPC decreases mortality in these cases is limited. Because a total deficiency of PC shows complete neonatal lethality, no animal model currently exists to address the mechanistic relationships between very low endogenous aPC levels and inflammatory diseases. Here, we show for the first time that novel genetic dosing of PC strongly correlates with survival outcomes following endotoxin (LPS) challenge in mice. The data provide evidence that very low endogenous levels of PC predispose mice to early-onset disseminated intravascular coagulation, thrombocytopenia, hypotension, organ damage, and reduced survival after LPS challenge. Furthermore, evidence of an exacerbated inflammatory response is observed in very low PC mice but is greatly reduced in wild-type cohorts. Reconstitution of low-PC mice with recombinant human aPC improves hypotension and extends survival after LPS challenge. This study directly links host endogenous levels of PC with various coagulation, inflammation, and hemodynamic end points following a severe acute inflammatory challenge.