Heterozygous MTHFR Research Articles

Assessment of Genetic Variants Linked to Susceptibility to Mechanical Prosthetic Valve Thrombosis

Prosthetic valve thrombosis (PVT) is a critical and life-threatening condition, driven by multifactorial etiologies including genetic predispositions. The study was designed as a single-center retrospective manner. Echocardiographic features and genetic test including Factor II Prothrombin G20210A, Factor V Leiden G1691A, Factor V R2 A4070G, ApoB-100 G10708A, ApoE C112R, ApoE R158C, MTHFR C677T, MTHFR A1298C, Factor XIII G103T (V34L), Beta fibrinogen G-455A, PAI-1 4G/5G, and HPA-1 (GPIIIa) T196C genotyping variations were assessed. We performed genetic tests in 175 patients with PVT [biologically women (n=124, 70.9%) with a mean age of 49.8 ± 13.1 years], and in 101 patients [biologically women (n=57, 56.4%) with a mean age of 54.7 ± 13.6 years] without thrombus formation. The thrombosis group was significantly younger compared to controls (p=0.004). The percentage of patients with mechanical aortic valves was significantly lower in the thrombosis group compared to controls (22.3 vs 34.7%, p=0.025). A significant difference was observed between the thrombosis and control groups regarding the genotype ratios of Factor II/Prothrombin (G20210A) (heterozygous, 6.8 vs 1%, p =0.043) and HPA-1 GPIIIa (T196C) (homozygous mutant, 7.8 vs, 0%, p=0.034) In addition, there was a significant association of heterozygous MTHFR (A1298C) variation with obstructive thrombosis compared to non-obstructive thrombosis (46.9 vs 29.2%, p=0.046). In conclusion, this is the first study to report a potential association between genetic variants including HPA-1 GPIIIa (T196C), Factor II/Prothrombin (G20210A), MTHFR (A1298C) and PVT, necessitating extensive further research and additional clinical consideration.

Hereditary thrombophilia as a possible risk factor for severe disease in COVID-19: a case series.

The risk factors that modulate one's susceptibility for severe COVID-19 have been well documented. Despite this, hypercoagulability remains an often overlooked risk factor for severe disease for COVID-19. Because COVID-19 infection is a risk factor for hypercoagulability, a reasonable presumption/hypothesis is that patients with hereditary thrombophilia would be at a higher risk of thrombotic complications associated with COVID-19 infection. This case report details two cases where previously unknown hereditary thrombophilias likely contributed to the mortality of COVID-19 patients. The first COVID-19 patient's cause of death was pulmonary thromboemboli from deep vein thrombosis due to heterozygous MTHFR C667T and heterozygous PAI-1 4G/5G mutations. The second COVID-19 patient's cause of death was an acute myocardial infarct due to a coronary artery thrombosis in the setting of heterozygous MTHFR A1298C and homozygous PAI-1 4G/5G mutations. In each case, COVID-19 infection was also considered contributory to death. The occurrence of these fatal thrombotic events in COVID-19 patients with hereditary thrombophilias raises questions as to whether this combination of thrombotic risk factors for hypercoagulability may have placed patients at a significant enough risk to experience these fatal thrombotic complications. Thus, while not sufficient alone to prove that SARS-CoV-2 patients with hereditary thrombophilias are at increased risk for thrombotic complications, these two cases indicate that further investigation is warranted into elucidating the relationship between thrombotic risk factors as it may identify an additional high-risk medical condition for COVID-19 and have important diagnostic and therapeutic ramifications.

A tale of A1298C mutation and recurrent Pulmonary Embolism: a rare association

Pulmonary Embolism (PE) and Deep Venous Thrombosis (DVT) represent critical manifestations within the spectrum of Venous Thromboembolic Disease (VTE). The MTHFR A1298C gene mutation occurs in approximately 7% to 12% of individuals in North America, Europe, and Australia. It is less prevalent among Hispanic populations, with a frequency of 4% to 5%, and even lower in Chinese and Asian populations, where it ranges from 1% to 4%. A 50-year-old male with a history of recurrent PE and long-term anticoagulation, despite effective anticoagulation, was not getting relieved. Genetic testing revealed a heterozygous MTHFR A1298C mutation which is very rare and elevated serum homocysteine levels, contributing to a hypercoagulable state. Comprehensive evaluation and management are essential to prevent further thromboembolic events in such patients.

Risk Factors of Thrombophilia-Related Mutations for Early and Late Pregnancy Loss.

Background and Objectives: This retrospective cohort study investigates the role of genetic thrombophilia in pregnant women experiencing early pregnancy loss compared to those with late pregnancy loss. Materials and Methods: Participants were categorized into early and late pregnancy loss groups based on gestational age. A total of 156 patients were included, out of which 103 had early-trimester pregnancy losses and 96 had multiple miscarriages. Results: The study revealed a synergistic effect of Factor V Leiden (FVL G1691A) and Methylenetetrahydrofolate Reductase (MTHFR C677T) mutations (coefficient 3.42). Prothrombin (PT) G20210A and β-Fibrinogen 455 G>A mutations exhibited a significant interaction (coefficient 1.98). Additionally, MTHFR A1298C and Plasminogen Activator Inhibitor-1 (PAI-1 4G/5G) mutations showed a significant interaction (coefficient 1.65). FVL G1691A and Endothelial Protein C Receptor (EPCR) allele A1/A2 mutations also demonstrated a significant association (coefficient 2.10). Lastly, MTHFR C677T and Glycoprotein IIb/IIIa T1565C mutations interacted significantly (coefficient 1.77). Risk factor analysis identified several mutations associated with early pregnancy loss, including PAI-1 4G/5G homozygous (OR 3.01), FVL G1691A heterozygous (OR 1.85), and MTHFR A1298C heterozygous (OR 1.55). Both homozygous and heterozygous MTHFR C677T mutations were significant risk factors (OR 2.38; OR 2.06), as was PT G20210A homozygous mutation (OR 1.92). The PAI-1 4G/4G homozygous variant posed a risk (OR 1.36). Late pregnancy loss was associated with MTHFR A1298C homozygous mutation (OR 3.79), β-Fibrinogen 455 G>A heterozygous mutation (OR 2.20), and MTHFR A1298C heterozygous mutation (OR 2.65). Factor XIII G1002T heterozygous mutation (OR 1.18) and PAI-1 4G/5G homozygous mutation (OR 2.85) were also significant risk factors. EPCR allele A1/A2 (OR 1.60) and A2/A3 (OR 1.73) mutations were identified as significant risk factors for late pregnancy loss. Furthermore, FVL G1691A homozygous mutation, PT G20210A homozygous mutation, MTHFR C677T heterozygous mutation, MTHFR A1298C heterozygous mutation, and EPCR allele A1/A2 were identified as significant risk factors for multiple miscarriage. Conclusions: This study highlights significant interactions and risk factors related to genetic thrombophilia mutations in different types of pregnancy loss, contributing valuable insights for miscarriage management guidelines.

A clinico-etiological profile of adult extrahepatic portal venous obstruction in patients from Northern India. Is it a novel subset of occult extrahepatic portal vein obstruction?

Background: Extrahepatic portal vein obstruction (EHPVO) is caused by occlusion and cavernomatous transformation of the portal vein. The EHPVO is well characterized in children. However, the same is not valid for adults. We aimed to evaluate the clinico-etiological profile along with the management of adult patients. Aims and Objectives: We evaluated the clinico-etiological profile along with the management and outcomes of adult patients presenting with EHPVO. Materials and Methods: In a descriptive, observational study, patients between ages 15 and 75 years diagnosed with EHPVO on ultrasonography abdomen were included in the study. Liver cirrhosis and malignancy were considered as an exclusion criterion. There was evaluation of clinical and imaging findings along with biochemical analysis, workup for thrombophilia, treatment given to the patients, and follow-up. Results: Out of total 109 patients enrolled in the study, the median age of patients was ±40.25. Main clinical features were dyspepsia, abdominal discomfort, and splenomegaly. Out of 109, 27.5% patients showed fatty liver and 5.5% had both splanchnic vein thrombosis and fatty liver. Idiopathic EHPVO in majority of patients (80%), adult EHPVO with polycythemia rubra vera in 7.33% patients, adult EHPVO with heterozygous MTHFR mutation in 7.33% patients, and adult EHPVO with antiphospholipid antibody in 3.66%. No mortality was seen in this 5-year observational study and majority of the patients, i.e., 96 (88.1%) did not require any treatment. Conclusion: Relatively benign nature of adult EHPVO was found in the selected group of patients. Majority of the cases in our study were idiopathic and few had positive thrombophilia profile.

Analytical Interference with Contrast Agents in Genetic Test Result for Thrombophilia

Background: Diagnostic and therapeutic drugs can change the laboratory results of patients by interfering with the measurement method and may compromise diagnostic efficiency. Incorrect results in biochemical tests used in the clinical follow-up of a patient during treatment may lead to improper applications. Unfortunately, this situation leads the clinician to misdiagnosis. Objective: The focus of this cross-sectional study is to investigate the effects of three different radiopaque substances commonly used in the clinic on thrombophilia molecular genetic results. Methods: Peripheric blood samples from three patients whose thrombophilia panel was planned to be studied were included. Blood samples that did not contain any radiopaque material or distilled water were studied as a control group. Except for the control group four different study groups were formed by adding distilled water, Ioversol, Fluorescein Na, and Gadobutrol. This radiopaque substances were added at a ratio of 1/10 to each patient's blood sample before DNA isolation. Prothrombin G20210A, MTHFR C677T, MTHFR A1298C, Factor V Leiden G169A and PAI-1 4G/5G mutations were studied by Real Time-PCR method. Results: There was no change at the thrombophilia panel results in the study groups compared with the control groups in patients 1 and 3. In patient 2, there was no change when the result of MTHFR C677T was compared to the results of blood+DW and blood+Gadobutrol. But there were alterations in blood+Ioversol and blood+Fluorescein Na samples; the result of heterozygous MTHFR C677T was observed to change to homozygous MTHFR C677T. Conclusion: This study showed that Ioversol and Fluorescein Na could change the results of the thrombophilia genetic analysis for MTHFR C677T mutation. It should be kept in mind that the results of the thrombophilia panel analysis may change after the injection of radiopaque substances.

Cerebellar stroke in a young female associated with elevated homocysteine levels and heterozygous MTHFR <em style="mso-bidi-font-style: normal;">C677T</em> gene:  A case report.

Homocysteine is an amino acid, which is an intermediate in the metabolism of methionine and cysteine. Elevated homocysteine levels are recognized as a cause for both arterial and venous thrombotic phenomena. Methylenetetrahydrofolatereductase -encoded by MTHFR gene- is the rate-limiting enzyme of the remethylation of homocysteine to methionine. Homozygous MTHFR T677T gene mutation can independently cause raised homocysteine levels and increase the risk of thrombosis whereas heterozygous MTHFR C677T gene mutation usually does with an acquired cause such as folate or vitamin B12 deficiency, and is with lesser risk for thrombosis. We report a case of a previously healthy 23-year-old female, who was excluded from other inherited and acquired thrombophilic conditions, but was found to be having heterozygous MTHFR C677T gene mutation and elevated level of homocysteine presented late with right cerebellar stroke. Therefore, when young patients present with thrombotic phenomena, homocysteine levels should be assessed in the absence of other common thrombophilic conditions.

The impact of hereditary thrombophilias in recurrent pregnancy loss

Introduction: Recurrent pregnancy loss (RPL) is defined as two or more consecutive pregnancy loss which occurs before the 20th weeks of pregnancies for the last menstrual period. Hereditary cause of thrombophilic gene mutations and polymorphism may play an essential role in RPLs. Material and Method: 291 women with a history of two or more consecutive abortions as a study group and 61 women without the history of miscarriages as a control group were included in a study. In this study we analysed the effects of Factor II Prothrombin mutation ,FV Leiden mutation, MTHFR C677T, MTHFT A1298C, PAI-1, ?-fibrinogen, Factor XIIIA (V34L) and Glycoprotein IIIa (L33P) polymorphisms on RPL by using pyrosequencing. Chi-square and multiple regression analysis were used for statistical analysis. Results: FII prothrombin mutation, FV Leiden mutation, MTHFR C677T, MTHFR A1298C, PAI1 and Beta fibrinogen were found statistically significant in the chi-square test. Heterozygous FV G1691A (OR:8.092, CI: 1.280-51.165), homozygous MTHFR A1298C (OR:17.621, CI: 3.644 - 85.203), Heterozygous MTHFR C677T (OR: 2.921 CI: 0.811-10.515), Homozygous MTHFR C677T (OR: 3.619 CI: 1.647-7.954), heterozygous MTHFR A1298C (OR: 5.989, CI: 2.574-13.934), homozygous PAI1 (OR: 8.756, CI: 2.805 -27.334), heterozygous PAI1 ( OR: 7.114, CI: 3.145- 16.096) homozygous FibrinogenG455A (4.085, CI: 1.438-11.610) were found statistically significant in logistic regression analysis for RPL(p<0.05). Discussion: This study indicated that there is a significant association between thrombophilias and RPL. Therefore, it is important to detect thrombophilic mutations in RPL.

Acquired and Inherited Thrombophilia Testing in Patients with Chronic Thromboembolic Pulmonary Hypertension: Value of Testing in an Academic Health Center

IntroductionChronic thromboembolic pulmonary hypertension (CTEPH) is classed as group 4 in the present classification of pulmonary hypertension. The pathophysiology of CTEPH is complex, mainly is a consequence of prior acute pulmonary embolism with failure of thrombi to resolve and the recent recognition of added small vessel changes which impacts long-term outcomes even after surgical management. The role of thrombophilia testing in this condition has been debated. Hence, we here analyzed the utility of thrombophilia testing in CTEPH from a center in a developing country.MethodsThis is a single institution (Narayana Health City, Bangalore); retrospective study including patients ≥ 18 years of age who underwent thrombophilia workup in a diagnosis of CTEPH from January 2019 till July 2021. Tests done to evaluate thrombophilia included factor V Leiden; prothrombin F20210A mutation; MTHFR gene mutation; Protein C, S, and antithrombin deficiency; lupus anticoagulant, anti-beta2 glycoprotein I (IgM and IgG) and anticardiolipin antibody (IgM and IgG); hyperhomocysteinemia and anti-nuclear antibody testing (ANA-IF). The study was approved by the ethics committee of the institute and was carried out in accordance with the principles of the declaration of Helsinki.Results and discussionThe study included 56 patients with a median age of 37 years (range 23-50), and 36 (64%) were males. Patients with recurrent venous thrombosis included 37 (66%), with the majority having thrombosis at 2 sites (53%; 22 patients with associated deep vein thrombosis). A family history of thrombosis was present in 4 patients. The majority of patients received vitamin K antagonists (76%), with the rest receiving direct oral anticoagulants (DOAC).Among the tests sent for acquired thrombophilia, ANA-IF and antiphospholipid antibody (APLA) were most frequently evaluated (94%). ANA-IF and APLA tests were positive in 5.6% and 30.1%, respectively. Among the APLA tests, Anti-beta2 glycoprotein I (IgM or IgG) was the most commonly detected antibody (13/46), followed by anticardiolipin antibody (IgG or IgM) (9/43) and lupus anticoagulant (7/40). Double and triple positive APLA were present in 3 and 4 patients, respectively. Homocysteine levels were high in 93.7% though only 16 patients were tested in this cohort.Among the tests for inherited thrombophilia, genetic tests (factor V Leiden, prothrombin F20210A mutation, and MTHFR gene mutation) were tested in only ~50%. Twenty-three percent were positive for heterozygous MTHFR followed by MTHFR compound heterozygous (10%) and heterozygous factor V Leiden heterozygous (10%). Antithrombin III, protein C, and S were tested in ~30% of patients. Antithrombin III was low in only 1 patient, with protein C and S assays being normal in all the patients.The cost analysis was calculated, showed a median of $364 (₹ 27,055) was spent per person on thrombophilia workup. The median cost incurred per patient for inherited thrombophilia workup was $232 (₹ 17,300) and for acquired thrombophilia was $132 (₹ 9814), respectively.ConclusionThis single-institution study on thrombophilia workup in CTEPH patients reveals that APLA was the most commonly performed test with high positivity rates of 30.1%. Among the inherited thrombophilia, the positivity rate of MTHFR mutation was highest (33.3%), with other tests having a low positivity rate (0-10%). Hence, we would recommend APLA testing in all patients with CTEPH considering its high positivity and clinical utility. Testing for other thrombophilias should be pursued judiciously especially in economically restrictive settings. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Cerebral Thromboses during Treatment of Childhood Acute Lymphoblastic Leukaemia.

Thromboembolic events are currently among the most serious complications occurring during treatment of acute lymphoblastic leukaemia (ALL), and account for cases of morbidity and even mortality. The role of L-Asparaginase, particularly that of E. coli L-Asparaginase (L-ASPA) in association or not with corticotherapy has been demonstrated by several authors. Most of the time, these thromboses are located within the central nervous system. Our retrospective study was carried out from December 2000 to December 2004 within 18 French centres. 902 children were prospectively included in the FRALLE 2000 protocol and were assigned to two risk groups: the A group with standard risk ALL (n=502) received dexamethasone during induction and 9 infusions of 6000 U/m2 of L-ASPA, while the B group with high risk ALL (n=400) was to receive prednisone. Both groups received a delayed intensification with dex and L-ASPA. 27 thrombotic events were reported, 16 of which were cerebrovascular accidents. The thromboses lay in the superior sagittal sinus (n=14), in the lateral sinus (n=7) and in the sinus rectus (n=2) and were revealed by convulsions in 30,7% of the cases and by diffuse neurologic signs in 68,7% of the cases. The course turned out positively 15 times out of 16, but one child died of haemorrhage. Hereditary thrombophilic factors were evaluable in 15 patients out of 16. We found out a congenital Protein C deficiency in one patient, but no Protein S or anti-thrombin deficiencies. We found out two Factor V G1691A heterozygous mutations and two Factor II G20210A heterozygous mutations. Five patients out of 14 have a MTHFR C677T mutation: one is homozygous in combination with a Factor V G1691A mutation, and 4 are heterozygous, isolated in two cases, in combination with a Factor V G1691A mutation in one case, and in combination with a Factor II G20210A in the other. Hereditary thrombophilic factors (isolated heterozygous MTHFR C677T mutations excepted) were thus reported in 31,2% (n = 5) of the cases.Conclusion: even if the frequency of thrombophilia may be underestimated in this study due to its retrospective design and non exhaustivity (APL antibodies, lipoprotein A were not investigated), it nevertheless points out CNS thrombosis represents an important cause of morbidity in childhood ALL treated with high dose steroid and L-ASPA. A prospective analysis of all thrombophilic factors seems justified in this setting for prevention possibly based on LMWH.

Frequency of hereditary prothrombotic risk factors in patients with Down Syndrome

Objective: Down Syndrome (DS) is defined as chromosome 21 trisomy and associated with cardiovascular system diseases. We aimed to study inherited thrombophilia genes (MTHFR A1298C, MTHFR C677T, Factor II G20210A, Factor V Leiden G1691A, Factor V Cambridge G1091C, Factor XIII, APOB, ITGB3, FVHR2, FGB, PAI-1 and ACE) in patients with DS. Materials and Methods: A total of 53 patients with DS (32 male and 21 female) were included in the study. Demographical, laboratory and clinical features of cases were recorded. 12-lead Electrocardiogram (ECG), transthoracic echocardiography and the inherited thrombophilia genes were evaluated. Results: The clinical and developmental defect findings of the patients were high. The 39.6% of patients had both heterozygous MTHFR C677T and heterozygous MTHFR A1298C carriers, the 18.9% of patients had homozygous MTHFR A1298C carriers, the 17% of patients had heterozygous Factor V Leiden G1691A carriers, the 43.4% of patients had 4G/4G carriers, the 34% of patients had 4G/5G variation carriers for PAI, the 22.7% of patients had heterozygous FactorXIII carriers, the 49.1% of patients had ins/del carriers and the 37.7% of patients had del/del variation carriers for ACE. All patients had at least one of the homozygous and/or compound heterozygous variations for the inherited thrombophilia. Conclusions: The patients with DS have a high risk for thrombosis-related cardiovascular system diseases. It may be said that the average life expectancy of individuals with DS may be increased by precautions (related to medical, social, lifestyle, etc.) to reduce complications associated with hereditary thrombophilia.

Mosaic Double Trisomy Associated with Miscarriage in a Patient with Recurrent Fetal Losses

A 25-year-old pregnant woman with a history of five previous miscarriages was admitted to our clinic. She had undergone abortion in her first pregnancy at 14 weeks gestation due to anhydramnios. Her second pregnancy had ended in a miscarriage at 19 weeks gestation due to premature rupture of membranes. Both of her first two pregnancies showed normal karyotypes. Her third pregnancy was noted to be an ectopic pregnancy leading to abortion at 5 weeks gestation. Afterwards, she experienced two more miscarriages at 7 weeks of gestation due to the lack of fetal cardiac activity which could not been investigated for chromosomal abnormalities.
 Her current pregnancy was also terminated at 9 weeks of gestation due to the lack of fetal cardiac activity. Cytogenetic analysis of abortion material using GTG banding technique revealed 48,XY,+12,+15[5]/46,XY[25] karyotype (7). Both parents were found to have normal karyotypes and physical examinations showed no obvious abnormalities. Thrombophilia evaluation revealed that she had heterozygous MTHFR C677T polymorphism.

The Folate Cycle Enzyme MTHFR Is a Critical Regulator of Cell Response to MYC-Targeting Therapies

Metabolic rewiring of neoplastic cells engenders metabolic liabilities that can be exploited to design innovative therapeutic strategies, including those to increase the therapeutic index of existing anticancer therapies. We hypothesized that metabolic perturbation may substantially influence cell response to therapies targeting major oncogenes which are involved in active hijacking of neoplastic cell metabolism. In that regard, MYC represents a paradigmatic oncogene as this transcription factor is deregulated in more than 50% of human cancers and reprograms many aspect of cell metabolism. MYC expression is controlled by clusters of super-enhancer genomic regions densely occupied by transcription factors and chromatin regulators ― including BET bromodomain proteins, and CDK7 and CDK9 kinases. Two cohorts of patients with Acute Myeloid Leukemia, AML (TCGA-LAML, n=198 and GSE14468, n=526) were queried with multiple gene sets in order to reveal a core of metabolic gene signatures, which are connected to the folate cycle, and whose activation was poorly correlated with an active MYC transcriptional program in AML. According to these data, we established that folate cycle disruption upon folic acid starvation consistently enhanced resistance to MYC targeting by BET or CDK7 inhibitors (JQ1, OTX015, THZ1) as well as BRD4-directed shRNAs in a large panel of human AML cell lines harboring a wide variety of genetic alterations (n=7), in MLL-translocated primary patient samples with AML (n=4), and in animals injected with MLL-AF9-positive leukemic cells. Using an shRNA-based screening approach against enzymes from the folate cycle, we revealed that the knockdown of the rate-limiting enzyme in the folate cycle, 5,10-methylenetetrahydroflate reductase (MTHFR), significantly increased resistance to OTX015 in AML cell lines (n=4) and in animals transplanted with Mthfr-depleted blasts. Previous reports have identified and extensively studied two common genetic variants in the MTHFR gene, C677T and A1298C, encoding two MTHFR enzyme variants with reduced activity in about 10% of Caucasians. We introduced in KG1a cells these two non-synonymous single nucleotide polymorphisms in MTHFR using CRISPR-Cas9, thereby generating isogenic cell lines exhibiting all combinations of variants. Although the clones which are heterozygous for any of the two variants had similar sensitivity to OTX015 as wild-type clones, 677 TT and 1298 CC homozygous KG1a clones were significantly more resistant to OTX015 than their wild-type counterpart, an effect that was alleviated by exogenous overexpression of wild-type MTHFR or supplementation of cells with the end-product metabolite synthesized by MTHFR, 5-CH3 THF. Consistent with these data, MLL-translocated patients displaying a homozygous and compound heterozygous MTHFR genotype for any of the two variants (n=8) responded significantly less to OTX015 than those with wild-type homozygous and heterozygous MTHFR genotypes (n=8). Finally, we established that the loss of a single copy of Mthfr which phenocopies in mice a partial impairment in MTHFR activity caused by non-synonymous single nucleotide polymorphisms on MTHFR, was sufficient to attenuate sensitivity to JQ1 of MLL-AF9-driven leukemias. Using metabolomics profiling, we pointed out that a major effect of folate cycle disturbance in AML cells is the intracellular accumulation of S-adenosyl-homocysteine, SAH, which is the downstream effector of MTHFR knockdown triggering BET inhibitor resistance. Given that SAH is a potent inhibitor of SAM-dependent methylation reactions, we determined that folate cycle impairment decreases H3K27 and H3K9 methyltransferase activities and subsequent methylation of H3K27 and H3K9 histone marks across the whole genome of AML cells. By combining ChIP- and RNA-sequencing approaches, we demonstrated that decreased methylation levels of H3K27 and H3K9 histone marks upon folate cycle alteration combined with BET inhibition activates SPI1 and IRF / Interferon signaling transcriptional programs. SPI1 knockdown significantly reduced the resistance to OTX015 of AML cells whose MTHFR expression was suppressed or MLL-AF9-transformed Mthfr knockout primary murine cells. Our data provide a rationale for screening MTHFR polymorphisms and the folate cycle status to exclude patients least likely and nominate those most likely to benefit from MYC-targeting therapies. Disclosures Dombret: CELGENE: Consultancy, Honoraria; AGIOS: Honoraria; Institut de Recherches Internationales Servier (IRIS): Research Funding. Stegmaier:Rigel Pharmaceuticals: Consultancy; Novartis: Research Funding.

PB2444 INHERITED THROMBOPHILIA IN EGYPTIAN CHILDREN: A 13 YEAR SINGLE CENTER STUDY

Background:Thrombophilia is most commonly due to genetic mutation affecting the amount or function of a protein in the coagulation system. Thrombosis can be arterial or venous with the latter being commoner and increasingly reported in children. There are few big studies describing inherited thrombophilia in the paediatric age group nonetheless in countries with high prevalence of consanguinity.Aims:So we assessed all our cohort diagnosed with inherited thrombophilia and correlated clinical data with genetic mutations.Methods:Retrospective study collecting data from the medical records of 52 children diagnosed with inherited thrombophilia and following up in Haematology Outpatient clinic, Cairo University Paediatric Hospital. Collected data was analysed and statistically correlatedResults:Our cohort included 52(30 males,22 females; 23% neonates, 19% < 6 months and 13% >6 months) children diagnosed with inherited thrombophilia. 30.7 % are of a consanguineous marriage and 12 % have a have a positive family history of thrombosis. 55.7% of patients presented in the first year of life(23% neonates, 19%< 6 months, 13% >6 months);28.8% presented at age 1 to 5years whereas 13.4% at the age of 5 to 10 years and only one child was > 10 years old. Thrombosis was venous in 39/52 (75%) patients, arterial in 12/52 (23.1%) and intra‐cardiac in only one(1.9%) patient. 36.5% of our cohort had recurrent thrombosis. Thrombotic events involved the cerebral vessels in 44.2% children, lower limb vessels in 32.7%, upper limbs in 7.7%, head and neck in 11.5% and the heart in 3.8%. 10 patients presented with both bleeding symptoms and thrombotic events. Thrombosis occurred spontaneously in 34.6% while 65.4% of children had risk factors; dehydration(65.4, fever and infection in nine patients (17.3%), surgery and blood sampling each in 7.7%, trauma and CVP insertion each in 3.8%.44 (84.6%) patients had more than one mutation and only 8 (15.4%). patients had a single mutation. 14(26.9%) had Factor V G1691A(13 heterozygous, 1 homozygous) whereas 10 had heterozygous Factor V 1299R (R2). 3(5.8%)patients had heterozygous Prothrombin 20210A, 9(17.3%) had Factor XIII V34L(7 heterozygous, 2 homozygous). 18 (34.6%), children had B‐Fibrinogen ‐455 G > A (heterozygous in 16, homozygous in 2). Uncommonly reported mutations in the literature but showing a higher prevalence in our cohort included PAI‐1 mutation in 24(46.2%, heterozygous in 19 and homozygous in 5); HPA‐1 in 15(28.8%, heterozygous in 7, homozygous in 8); ACE in 28(53.8%, heterozygous in (n = 16), homozygous in (n = 12); APO E mutations in 20(38.5%, heterozygous in 6,homozygous in 14). Twenty (38.5%) patients had MTHFR C6777T,heterozygous in 17 and homozygous in 3 whereas and another 20 patients had heterozygous MTHFR 1298C mutation. 3 patients had protein C(PC) deficiency which together with MTHFR C6777T mutation usually present at a very early age.26 (50%) had complications; amputation (15.4%) blindness and developmental delay each in 7.7%, renal atrophy, hydrocephalus, and death each in 3.8%, and ischemic insult (1.9%).Summary/Conclusion:Egyptian children having more than one heterozygous mutation even if weakly thrombophiliac are prone to develop significant thrombotic events when exposed to minor risk factors or spontaneously

P-220 - MTHFR, TSER and DPYD gene mutation is associated with toxicity and response in pre-operative chemo-radiotherapy for local advanced rectal cancer

Introduction: Radiotherapy and 5 FU based chemotherapy is the most common pre-operative regimen used for cT3-T4, N1 rectal cancer (RC). Evaluation of predictive markers of response and toxicity to radio-chemotherapy is a challenging approach for patients (pts) and drug selection. In the present experience we have analyzed the predictive role of the genetic polymorphisms (MTHFR, TSER and DPYD) on toxicity and response to pre-operative radio-chemotherapy. Methods: We have enrolled eighteen patients with locally advanced RC treated with pre-operative radiotherapy and fluoropyrimidines based chemotherapy. Genetic polymorphisms of MTHFR C677T, MTHFRA 1298C, DPYD IVS 14 + 1G>A, DPYDA 2846T, DPYD T 1679 G, TSER 28 bp VNTR were analyzed by PCR and pyrosequencing of genomic DNA extracted from peripheral blood samples. Genetic markers were correlated with toxicity to treatment (chemotherapy and radio-chemotherapy) and clinical response. Results: Patients characteristics were: male 15 pts, female 3 pts, median age 66 years, ECOG PS 0-1 all pts. We found DPYD IVS 14 + 1 G>A G/G homozygous wild type, DPYD A2846T, T/T homozygous wild type and DPYD T1679 g, T/T homozygous wild type in 100% of pts, homozygous wild type MTHFR C677T in 10% of pts, MTHFR C677T homozygous mutated in 50% of pts, heterozygous MTHFR A1298C in 60% of pts and homozygous wild type MTHFR A 1298C in 40% of pts. Adverse events G-3 (diarrhea, neutropenia, asthenia, mucositis) were observed in 60% of pts with heterozygous MTHFR A 1298C and in 10% of pts with homozygous mutated MTHFR C 677t treated with chemo radiotherapy combination. DPYD homozygous wild type was not associated with severe toxicity. Rectal surgery with TME/TEM will be performed 8 weeks after the end of pre-operative chemo-radiotherapy. We obtained 9 pathological complete response and 9 partial pathological response. Adjuvant chemotherapy was well tolerated without G3-G4 adverse events. Five pts with pathological complete response were treated with Transanal Endoscopic Microsurgery (TEM) and they are alive without recurrence to twelve months after surgery. Conclusion: Concomitant assessment of genetic polymorphisms of MTHFR and DPYD is promising to predict severe toxicity during preoperative chemo-radiotherapy approach for pts with locally advanced rectal cancer. This result does not exclude the need to consider other non-genetic factors that might influence the individual enzyme activities.

MTHFR, TSER and DPYD gene mutation is associated with toxicity and response in pre-operative chemo-radiotherapy for local advanced rectal cancer

Background: Radiotherapy and 5 FU based chemotherapy is the most common pre-operative regimen used for cT3-T4, N1 rectal cancer (RC). Evaluation of predictive markers of response and toxicity to radio-chemotherapy is a challenging approach for patients (pts) and drug selection. in the present experience we have analyzed the predictive role of the genetic polymorfisms (MTHFR, TSER and DPYD) on toxicity and response to pre-operative radio-chemotherapy. Materials and methods: We HAVE enrolled sixteen patients with locally advanced RC treated with pre-operative radiotherapy and fluoropyrimidines base chemotherapy. Genetic polymorphisms of MTHFR C677T, MTHFRA 1298C, DPYD IVS 14 + 1G>A, DPYDA 2846T, DPYD T 1679 G, TSER 28 bp VNTR were analyzed by PCR and pyrosequensing of genomic DNA extracted from peripheral blood samples. Genetics markers were correlated with toxicity to treatment (chemotherapy and radio-chemotherapy) and clinical response. Results: Patients characteristics were: male 13 pts, female 3 pts, median age 66 years, ECOG PS 0-1 all pts. We found DPYD IVS 14 + 1 G>A G/G homozygous wilde type, DPYD A2846T, T/T homozygous wilde type and DPYD T1679 g, T/T homozygous wilde type in 100% of pts, homozygous wilde type MTHFR C677T in 10% of pts, MTHFR C677T homozygous mutated in 50% of pts, heterozygous MTHFR A1298C in 60% of pts and homozygous wilde type MTHFR A 1298C in 40% of pts. G3-G4 advers events (diarrhea, neutropenia, asthenia, mucositis) were observed in 60% of pts with heterozygous MTHFR A 1298C and in 10% of pts with homozygous mutated MTHFR C 677t. treated with chemo-radiotherapy combination. DPYD homozygous wilde type was not associated with severe toxicity. Rectal surgery with TME will be performed 8 weeks after the end of pre-operative chemo-radiotherapy. We obtained 7 patological complete response and nine partial patological response. Adjuvant chemotherapy was well tolerated without G3-G4 adverse events. Three pts with patological complete respose were treated with Transanal Endoscopic Microsurgery (TEM) and they are alive without recurrence to twelve months after surgery. Conclusion: Concomitant assesment of genetic polymorphisms of MTHFR and DPYD is promising to predict severe toxicity during preoperative chemo-radioterapy approach for pts with locally advanced rectal cancer. This result does not exclude the need to consider other non-genetic factors that might influence the individual enzyme activities.

Asymptomatic Duodenal Penetration by Inferior Vena Cava Filter: 3-Year Follow-up

INTRODUCTION: Inferior vena cava (IVC) filters are used to reduce the risk of thromboembolic events in subjects who are either not a candidate for anticoagulant therapy (ACT) or have failed ACT. Complications of IVC filters could be either early (bleeding, infection, acute venous thrombosis, hematoma and arteriovenous fistula formation) or late (filter migration and chronic thrombosis/recurrent thromboembolism). IVC filter penetration of the surrounding structures including bowel (duodenum), is a known although rare complication which can manifest as abdominal pain, gastrointestinal bleeding, cava-duodenal fistula, or small bowel obstruction. We present a rare case of asymptomatic duodenal penetration by IVC filter which was managed conservatively. CASE REPORT A 64-year-old male with history of multiple, recurrent DVTs and pulmonary embolism secondary to heterozygous MTHFR gene mutation presented to our facility 3 years ago for progressively worsening dysphagia. He had Greenfield IVC filter placed a few years back and was on long term ACT. Esophagogastroduodenoscopy(EGD) incidentally revealed a piece of metal protruding from the second portion of the duodenal wall, as shown in figure 1.CT scan of the abdomen and pelvis showed multiple IVC filter struts extending beyond the IVC wall with one of the struts extending anteriorly to penetrate the duodenal wall, as in figure 2. IVC venography confirmed CT scan findings, showing four struts of a patent IVC filter extending beyond the IVC wall. Vascular surgery (VS) and interventional radiology (IR) recommended conservative management in the absence of any symptoms. He remained asymptomatic for the next three years. Repeat EGD performed 3 years later revealed unchanged IVC filter strut in the duodenum, as shown in figure 3.Figure: EGD performed in 2013 showing IVC filter strut in duodenum.Figure: CT scan of the abdomen and pelvis showing multiple IVC filter struts extending beyond the IVC wall, with one of the struts penetrating duodenal wall.Figure: EGD performed in 2016 showing IVC filter strut at the same location in duodenum.DISCUSSION IVC filter migration into the GI tract is extremely rare and patients are usually symptomatic. Duodenum is the most common extra-caval involved organ. Current literature directs surgical treatment of patients with symptomatic duodenal perforation, however, there are no consensus guidelines for management of asymptomatic IVC filter penetrations in GI tract. Such cases should be managed by a multidisciplinary team of IR, VS and gastroenterologist. CONCLUSION Our patient was managed successfully with a non-surgical approach and remained asymptomatic during next 3 years.

Thrombophilic gene polymorphisms and recurrent pregnancy loss in Greek women.

Recurrent pregnancy loss (RPL) is a multifactorial disorder. The aim of this study was the detection of various genetic polymorphisms and their correlation to RPL, in Greek women. The impact of 12 thrombophilic polymorphisms was evaluated, among 48 Greek women with a history of RPL, vs 27 healthy parous women. Multiplex PCR and in situ hybridization on nitrocellulose films were performed, to investigate 12 genetic polymorphisms previously reported as risk factors for RPL. Heterozygous FV Leiden, homozygous PAI-1 4G/4G, heterozygous MTHFR C677T, homozygous MTHFR A1298C, as much as the combined thrombophilic genotypes MTHFR 677T + ACE Ι/D, MTHFR 677T/1298C + ACE D/D, ACE I/D + b-fibrinogen -455G/A, FV HR2 + b-fibrinogen -455G/A showed a correlation as risk factors for RPL, whereas the rest of the investigated polymorphisms and their combinations did not render statistically significant differences between the two groups in study. The results of this study, as well as those of similar studies, concerning the detection of genetic, environmental, and physiological factors underlying RPL, will prove of critical significance in the investigation and treatment of thrombophilic predisposition, in cases of RPL.

Successful management of hereditary angioedema during pregnancy in a patient with heterozygous MTHFR mutation

Successful management of hereditary angioedema during pregnancy in a patient with heterozygous MTHFR mutation

Acquired Thrombotic Thrombocytopenic Purpura (TTP) in a patient with heterozygous MTHFR C677T mutation and hyperhomocysteinemia – a case report

Acquired Thrombotic Thrombocytopenic Purpura (TTP) in a patient with heterozygous MTHFR C677T mutation and hyperhomocysteinemia – a case report