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PubMed2003

The des-gamma-carboxy prothrombin index is a new prognostic indicator for hepatocellular carcinoma.

BACKGROUND: Des-gamma-carboxy prothrombin (DCP) has been reported to be an important prognostic factor in patients with hepatocellular carcinoma (HCC). Recently, a monoclonal antibody, 19B7, which recognizes the Gla domain of DCP, has been identified. The 19B7 antibody recognizes an epitope different from that recognized by MU-3, which is another antibody against DCP. In this study, the authors investigated the measurement of DCP using the antibodies MU-3 and 19B7, respectively, as a prognostic factor for patients with HCC who had solitary, small tumors and or Child Stage A HCC. METHODS: One hundred four patients with HCC who had solitary, small tumors or Child Stage A tumors were enrolled in the study between 1991 and 2001. All patients were treated and were followed for a mean of 3.2 years. The authors analyzed the correlation between the DCP Index (DCP measured by MU-3 and DCP measured by 19B7) and patient prognosis. The patients were classified into 3 groups based on their DCP Index: 1) DCP negative (DCP < 40 milli arbitrary unit (mAU)/mL)); 2) low DCP Index (DCP > or = 40 mAU/mL; MU-3:19B7 ratio, < 3.0; and 3) high DCP Index (DCP > or = 40 mAU/mL; MU-3:19B7 ratio, > or = 3.0). RESULTS: The survival rate for patients in the high DCP Index group was lower compared with the survival rate for patients in the DCP-negative group and was significantly lower compared with the survival rate for patients in the low DCP Index group. In a univariate Cox proportional hazards model, the positive factors were high DCP Index and low DCP Index. Among the positive predictive factors that were analyzed using a multivariate Cox proportional hazards model were age (hazard ratio, 3.27; P = 0.006), low DCP Index (hazard ratio, 2.87; P = 0.012), and high DCP Index (hazard ratio, 12.3; P < 0.0001). CONCLUSIONS: The prognosis of patients who had a high DCP Index score was poorer compared with patients who had a low DCP Index score and patients who were classified as DCP negative. The authors concluded that the DCP Index is a prognostic indicator for patients with HCC.

Aged↗
PubMed2004

Renal prothrombin: quantification of mRNA using reverse transcription-polymerase chain reaction in a rat model.

Attempts to quantify renal prothrombin (PT) have failed due to interference of its hepatic counterpart. In order to gauge PT synthesized by the kidney, the expression of PT mRNA was compared in renal and hepatic tissues of rats. PT mRNAs were quantified, using quantitative competitive reverse transcription-polymerase chain reaction (RT-PCR), from RNA extracts of kidneys and livers of ten hooded Wistar rats. To control variations in sample preparation, the amount of PT transcript in each sample was normalized to the amount of its beta-actin transcript. The median ratio of PT to beta-actin transcript of 0.0011 (with a mean +/- standard deviation (SD) of 0.0010 +/- 0.0002, range 0.0007-0.0014) in the renal tissues was significantly (p < or = 0.001) lower than its corresponding value of 0.3669 (with a mean +/- SD of 0.3729 +/- 0.0716, range 0.2718-0.4675) in the hepatic tissues. Thus, expression of PT mRNA in the rat kidney was almost 300-fold less as compared with its expression in hepatic tissue.

Actins↗
PubMedDate not supplied

The acquired vitamin K-dependent gamma-carboxylation deficiency in hepatocellular carcinoma involves not only prothrombin, but also protein C.

Protein C, one of the vitamin K-dependent plasma proteins synthesized in the liver, was measured immunologically in normal subjects (n = 20), patients with hepatocellular carcinoma (n = 60), liver cirrhosis (n = 60), acute hepatitis (n = 16), chronic hepatitis (n = 19), malignant neoplasms other than hepatocellular carcinoma (n = 35) and patients on warfarin treatment (n = 20). We also assayed gamma-carboxyglutamic acid-complete (carboxylated) protein C in these population by using a monoclonal antibody directed against human protein C, JTC-1, which recognizes the gamma-carboxyglutamic acid domain-related conformational change induced by metal ions. We demonstrated that the plasma of patients with hepatocellular carcinoma contains considerable amounts of gamma-carboxyglutamic acid-incomplete protein C, evidenced by the significantly reduced protein C:gamma-carboxyglutamic acid/protein C:antigen ratios in hepatocellular carcinoma as compared to those seen in normal controls, other liver diseases and other malignant neoplasms (p less than 0.01). In two patients with hepatocellular carcinoma with the reduced protein C:gamma-carboxyglutamic acid/protein C:antigen ratios, successful treatment (transcatheter hepatic arterial embolization or lipiodolization of antitumor agent) led to the very rapid normalization of the ratios. Intravenous administration of vitamin K, however, induced no such effects in three other patients with hepatocellular carcinoma with the abnormality. We conclude that the impaired vitamin K-dependent gamma-carboxylation observed in patients with hepatocellular carcinoma involves not only prothrombin, but also protein C, and that the impairment is not due to vitamin K deficiency.

1-Carboxyglutamic Acid↗
PubMed1987

Deriving the generic structure of the fibronectin type II domain from the prothrombin Kringle 1 crystal structure.

The proposed homology between the fibronectin type II domain and the Kringle domains of blood clotting and fibrinolytic proteins has been examined in three dimensions by substituting the type II sequence into the bovine prothrombin Kringle 1 tertiary structure, determined by X-ray crystallographical methods at 3.8 A. Structural substitution of aligned amino acids of the type II domains and the Kringle produces a compact chain fold and deletions and insertions in the type II sequence are accommodated within the modelled structure. This confirms the structural homology between the two domains and verifies the sequence alignment and common evolution of the type II and Kringle units. The two structures contain homologous hydrophobic cores, centered around the two disulphide bridges which link conserved beta-type strands. Gross differences between the two domains occur in exterior loops and potential functional sites in these regions of the type II structures as found in fibronectin, Factor XII and seminal fluid protein PDC-109 are proposed. We suggest that the domains evolved from a common ancestral protein comprising the hydrophobic core and disulphide arrangement which later diverged to bind different macromolecules through adaptation of the external loops.

Amino Acid Sequence↗
PubMed2004

Increased prothrombin time and platelet counts in living donor right hepatectomy: implications for epidural anesthesia.

The risks and benefits of adult-to-adult living donor liver transplantation need to be carefully evaluated. Anesthetic management includes postoperative epidural pain relief; however, even patients with a normal preoperative coagulation profile may suffer transient postoperative coagulation derangement. This study explores the possible causes of postoperative coagulation derangement after donor hepatectomy and the possible implications on epidural analgesia. Thirty donors, American Society of Anesthesiology I, with no history of liver disease were considered suitable for the study. A thoracic epidural catheter was inserted before induction and removed when laboratory values were as follows: prothrombin time (PT) > 60%, activated partial thromboplastin time < 1.24 (sec), and platelet count > 100,000 mmf pound sterling (mm3). Standard blood tests were evaluated before surgery, on admission to the recovery room, and daily until postoperative day (POD) 5. The volumes of blood loss and of intraoperative fluids administered were recorded. Coagulation abnormalities observed immediately after surgery may be related mostly to blood loss and to the diluting effect of the intraoperative infused fluids, although the extent of the resection appears to be the most important factor in the extension of the PT observed from POD 1. In conclusion, significant alterations in PT and platelet values were observed in our patients who underwent uncomplicated major liver resection for living donor liver transplantation. Because the potential benefits of epidural analgesia for liver resection are undefined according to available data, additional prospective randomized studies comparing the effectiveness and safety of intravenous versus epidural analgesia in this patient population should be performed.

Adult↗
PubMed1995

The role of tumor markers in the diagnosis of hepatocellular carcinoma, with special reference to the des-gamma-carboxy prothrombin.

The assessment of new and more sensitive serum markers for hepatocellular carcinoma (HCC) represents a useful contribution to the diagnosis of small liver tumors, still amenable by surgery. We evaluated the efficacy of the tumor markers proposed during recent years for the study of HCC: alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), serum ferritin (SF), tissue polypeptide antigen (TPA), and, finally, the more recently proposed des-gamma-carboxy prothrombin (DCP). Of the 227 patients included in this retrospective study, 111 had HCC, and 85 of these were also cirrhotic. The remaining 116 patients, considered as the control group, included 23 patients with liver metastases from colorectal cancer, 26 with benign hepatic lesions, 20 with tumors other than HCC without hepatic metastases, and 47 with other liver diseases. For each single tumor marker, the sensitivity, specificity, positive and negative predictive values, diagnostic accuracy, and Younden index were assessed. AFP and DCP proved to be the most effective, with sensitivity, specificity, and diagnostic accuracy of 54.9%, 97.4%, and 76.6% and of 53.3%, 88.1%, and 71.1%, respectively. The same parameters evaluated for combined use of the two markers were 74.2%, 87.2%, and 80.9%, respectively. Analysis of the other markers produced no further significant contribution. Of the 111 patients with HCC, 35 (33.3%) were positive for both AFP and DCP, 43 (41%) were positive for one of them, and 27 (25.7%) were completely negative. In the 44 patients who underwent liver resection or transplantation, DCP correlated significantly with the histological presence of microvascular thrombosis, the major factor determining long-term survival after curative surgery. As a tumor marker for HCC, DCP is at least as effective as AFP; the combined use of AFP and DCP significantly improves the chances of identifying HCC by serodiagnosis.

Adolescent↗
PubMed2006

Prolongation of the prothrombin time and activated partial thromboplastin time in children with sickle cell disease.

BACKGROUND: Patients with sickle cell disease (SCD) have high rates of perioperative complications, including bleeding 1,2. PROCEDURES: We conducted a retrospective review of pre-operative coagulation studies in pediatric patients with SCD followed by a prospective study of 100 well children with SCD to determine the prevalence of abnormal coagulation screening tests, and to evaluate potential etiologies. RESULTS: In the retrospective study, 32/84 (38.1%) had a prolonged prothrombin time (PT), compared to 8/100 in the prospective study. Prolongations of the activated partial thromboplastin time (aPTT) were less common. Children in the prospective study with prolonged PTs had significantly lower levels of Factor V and VII compared to those with normal PTs. Factor VII levels were <50% in 4/8 with long PTs, compared to 3/92 with normal PTs, P=0.001. Though retrospectively, several patients had normalization of their PT with vitamin K, there was no laboratory evidence of vitamin K deficiency in the prospective study. In the retrospective analysis, six of seven children who had pre-operative coagulation studies and significant intraoperative blood loss had prolonged PTs (P=0.04). CONCLUSIONS: Children with SCD admitted for surgical procedures were more likely to have prolonged PTs than those tested at a well visit. There was intra-patient variability in coagulation studies that may be related to clinical status, hepatocellular dysfunction, and/or increased clotting factor consumption. Future well-designed prospective studies to determine whether abnormal coagulation studies are associated with an increased risk of perioperative bleeding in children with SCD are necessary.

Adolescent↗
PubMed1988

Lysine/fibrin binding sites of kringles modeled after the structure of kringle 1 of prothrombin.

The Lys binding site of kringle 1 and 4 (K1 and K4) of plasminogen (PG) has been modeled on the basis of the three-dimensional structure of kringle 1 of prothrombin and 300- and 600-MHZ proton nuclear magnetic resonance observations. These structures were then compared to the corresponding regions of modeled kringle 1 and 2 of tissue plasminogen activator (PA). The coordinates of the modeled structures have been refined by energy minimization in the presence and absence of epsilon-aminocaproic acid ligand in order basically to remove unacceptable van der Waals contacts. The binding site is characterized by an apparent dipolar surface, the polar parts of which are separated by a hydrophobic region of highly conserved aromatic residues. Zwitterionic ligands such as Lys and epsilon-aminocaproic acid form ion pair interactions with Asp55 and Asp57 located on the dipolar surface; the latter are also conserved in all the Lys binding kringles. The cationic center of the dipolar surface is Arg71, in the case of PGK4, and is composed of Arg34 and Arg71 in PGK1. The doubly charged anionic/cationic interaction centers of the latter might account for the larger binding constants of PGK1 for like-ligands but the modeling suggests that PGK4 might be kinetically faster in binding bulkier ligands. The binding site region of PAK2, which also binds Lys, resembles those of PGK1 and PGK4. Since PAK2 lacks both cationic center Arg residues, ligand carboxylate binding appears to be accomplished though an imidazolium ion of His64, which is located just below the outer surface of the kringle.

Amino Acid Sequence↗
PubMed1992

Highly polymorphic region of the human prothrombin (F2) gene.

We have found a highly polymorphic region in the human prothrombin gene. Our sequence differed from that previously reported at as many as 6 positions in a 225-bp stretch spanning exon 6 and its flanking regions; four of these positions were related to endonuclease restriction sites for AluI, HpaII(MspI), MboII, and NcoI. AluI and HpaII digested all alleles of the Japanese tested. MboII and NcoI restriction fragment length polymorphisms are highly heterozygous and not in linkage disequilibrium; they thus serve as good human DNA markers.

Amino Acid Sequence↗
PubMed1992

Detection of a new polymorphism of the human prothrombin (F2) gene by combination of PASA and mutated primer-mediated PCR-RFLP.

A new polymorphism of the human prothrombin (F2) gene was detected by a combination of polymerase chain reaction (PCR) amplification of specific alleles (PASA) and mutated primer-mediated PCR restriction fragment length polymorphism (PCR-RFLP). The method is simple and useful for detecting polymorphisms and mutations. The new polymorphism of C1 and C2 examined by this method is highly heterozygous and serves as a good human DNA marker.

Base Sequence↗
PubMed1994

Increased prothrombin activation in a patient with congenital afibrinogenemia is reversible by fibrinogen substitution.

We describe a patient with congenital afibrinogenemia who showed elevated prothrombin activation fragments (F1 + 2) indicating increased thrombin formation. This finding was unexpected since it has hitherto been thought that patients with congenital hypo- or afibrinogenemia have no evidence of increased utilization or accelerated consumption of coagulation factors. No other possible reasons for the elevation of F 1 + 2 were found. Upon fibrinogen substitution F1 + 2 decreased and were again increasing when fibrinogen concentration in plasma fell to very low levels. These findings raise the question of whether increased thrombin formation should be understood as a compensatory mechanism in congenital afibrinogenemia.

Adolescent↗
PubMed1985

Protein C antigen in prothrombin complex concentrates: content, recovery and half life.

Protein C, a potent anticoagulant, has been detected in large amounts in some prothrombin complex concentrates (PCC). We extended these findings to eight PCC commercially available in West Germany detecting 0.82 to 1.92 plasma equivalent units of protein C antigen (PC:Ag) per unit factor IX. Infusion of PCC in four patients on stable oral anticoagulation resulted in a recovery of 58.6 +/- 10.9%. Estimated from the decrease in plasma levels of PC:Ag half life was 7.9 +/- 0.6 h.

Enzyme-Linked Immunosorbent Assay↗
PubMed1991

Cooperativity in the calcium ion-induced quenching of the intrinsic fluorescence of a series of normal and GLA-deficient bovine prothrombin fragment 1 molecules.

Ca2+ titrations of the intrinsic fluorescence of a series of gamma-carboxyglutamic acid (GLA)-deficient bovine prothrombin fragments 1 yield response Hill plot parameters useful for characterization of the metal ion-binding process. 11-, 10-, and 9-GLA fragments 1 exhibit Tm (the (Ca2+)total concentration at which ln (B/F) = 0 in the response Hill plot) values between 0.2 and 0.3 mM. A 22-fold increase in Tm to 5.4 mM is observed for 8-GLA fragment 1. Tm decreases to 3.8 mM for the 7- and 6-GLA proteins. The value of h, about 2.8 +/- 0.2 for 11-, 10-, and 9-GLA fragments 1, abruptly decreases to 1.2-1.3 for 8-, 7-, and 6-GLA fragments 1. The observed degree of quenching induced by saturating levels of calcium ions is affected by both changes in the intrinsic fluorescence of the metal ion-free proteins and in the maximum possible degree of quenching in the presence of calcium. The kinetic characteristics of the calcium ion-induced quenching of the intrinsic fluorescence of 6-GLA fragment 1 are identical to those observed in 10-GLA fragment 1, suggesting that the fluorescence quenching observed in the 6- and 10-GLA fragments 1, while different in magnitude, involves similar processes. Observation of an abrupt change in the relative electrophoretic mobilities of 11- to 9-GLA fragments 1 compared to 8- to 6-GLA fragments 1, in the absence or presence of Ca2+, suggests the existence of a major protein conformation change which occurs concomitantly with the noted changes in Tm and h response Hill plot parameters. Molecular mechanics calculations suggest a structural hypothesis unifying these observations. Central to this model is the presumption of the existence of hydrogen bond-mediated interactions between metal ion-binding sites.

1-Carboxyglutamic Acid↗
PubMed1988

Prediction of the secondary structures of bovine blood coagulation factor IX, factor X, and prothrombin.

The secondary structures of bovine blood coagulation factors IX and X, as well as that of bovine prothrombin, were predicted on the basis of a computerized combination of the Chou-Fasman and Burgess algorithms. Refinements in the predictions were made after consideration of the content of various secondary structures, as determined by circular dichroism studies of these same proteins. The final turn assignments were in good agreement with those assigned with use of an algorithm involving pattern matching of beta-turns in proteins of known structure.

Animals↗
PubMed1991

Clinical usefulness of des-gamma-carboxy prothrombin assay in early diagnosis of hepatocellular carcinoma.

Des-gamma-carboxy prothrombin (DCP) was evaluated as a serological marker for hepatocellular carcinoma (HCC), particularly in patients with early HCC. In 1192 patients with various diseases, plasma DCP levels were measured by a newly developed enzyme immunoassay method using an anti-DCP monoclonal antibody. Of the 254 patients with HCC, 143 (56%) had abnormal DCP levels of greater than 0.1 AU/ml. In contrast, elevated DCP levels were rarely observed in patients with chronic hepatitis, liver cirrhosis, metastatic liver cancer, and other malignant tumors. Because no correlation was observed between DCP and alpha-fetoprotein (AFP), the combined measurement of these two complementary markers appears to be useful in the diagnosis of HCC. Since normal levels were observed in 29 of 30 patients (97%) with small liver tumors measuring 2 cm or less in diameter, the diagnostic application of the DCP assay to small liver tumors is limited. However, in patients with tumors larger than 2 cm, the plasma DCP assay may even be more useful than AFP. Among 46 patients with liver cirrhosis or chronic hepatitis who subsequently developed HCC, significantly increased DCP and AFP levels were observed in nine patients (20%) and 14 patients (30%), respectively, when a tumor was detected. When the results of both assays were combined, 19 patients (41%) had elevated levels of one or both markers. Although the plasma DCP assay alone is not sensitive enough to detect early small liver cancers, it could be applied as a complementary tumor marker together with AFP.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Clinical evaluation of plasma des-gamma-carboxy prothrombin as a marker protein of hepatocellular carcinoma in patients with tumors of various sizes.

We measured des-gamma-carboxyprothrombin (DCP) (prothrombin induced by vitamin K absence or antagonist-II, abbreviated as PIVKA-II) by a newly developed enzyme immunoassay using an anti-DCP monoclonal antibody in 665 human subjects, of which 112 were patients with hepatocellular carcinoma (HCC). PIVKA-II was elevated to more than 0.1 AU/ml in 54 of the 112 patients (48.2%) with HCC, while it was positive only in 7.1% of those with liver cirrhosis and 3.1% of those with chronic hepatitis. Three patients with elevated PIVKA-II greater than 0.1 AU/ml who had been diagnosed as having liver cirrhosis by ultrasonography and computed tomography at the start of this study developed a diffuse type of HCC three or six months later, which was detected by angiography. No obvious correlation was observed between plasma PIVKA-II concentration and serum alpha-fetoprotein (AFP) level in HCC patients. Of the 112 HCC patients, 40.2% showed an increase in AFP to above 200 ng/ml. In the remaining patients, 32.8% had a PIVKA-II concentration greater than 0.1 AU/ml. In these patients with a negative or low serum AFP concentration, PIVKA-II proved to be a valuable tumor marker for laboratory diagnosis of HCC. Among them, 59.8% tested positive for PIVKA-II and/or AFP. Thus, combination assay with PIVKA-II and AFP seems useful for increasing the accuracy of laboratory diagnosis of HCC. None of patients with a solitary tumor smaller than 2 cm had elevated PIVKA-II. In patients with larger-sized and multiple HCC, positive results of elevated PIVKA-II were more frequent than those of increased AFP.(ABSTRACT TRUNCATED AT 250 WORDS)

Biomarkers↗
PubMed1987

Human genes encoding prothrombin and ceruloplasmin map to 11p11-q12 and 3q21-24, respectively.

The gene for human prothrombin, or factor II (F2) has been assigned to 11p11-q12 by the combined use of a panel of somatic cell hybrid DNAs and in situ hybridization, using both cDNA and genomic probes. In addition, the cDNA probe for F2 recognizes a homologous sequence which has been tentatively mapped to the X chromosome. Similar approaches have been used to confirm the assignment of the ceruloplasmin gene, but to regionally localize it more proximally than previously reported (3q21-q24). These results provide further evidence that genes encoding the coagulation factors and related proteins are dispersed throughout the human genome.

Ceruloplasmin↗
PubMed1992

Monitoring prothrombin fragment 1 + 2 during initiation of oral anticoagulant therapy after intracoronary stenting.

Patients with intracoronary stent implantation are treated with aggressive anticoagulant and antiplatelet therapy consisting of high-dose heparin, phenprocoumon, acetylsalicylic acid, dipyridamole, and the infusion of dextran to prevent a subacute thrombotic occlusion of the stented segment. In an effort to optimize this treatment by reducing both imminent bleeding complications and subacute thrombotic occlusion, the concentrations of prothrombin fragment 1 + 2 (F 1 + 2) were determined after intracoronary Palmaz-Schatz stent implantation in 19 consecutive patients. The F 1 + 2 concentrations after stent implantation and before the initiation of oral anticoagulant therapy (OAT) were 0.35 nm/l and 0.25-0.53 nm/l (median and 25th-75th percentile), versus 0.74 nm/l and 0.52-0.78 nm/l, in healthy subjects and 0.61 nm/l and 0.30-1.02 nm/l in 15 patients with ongoing proximal DVT. Nine days after initiation of OAT, F 1 + 2 concentrations in both patient groups had not yet reached levels observed in patients with OAT in the stable state (0.16 nm/l, 0.12-0.26 nm/l; n = 76; P less than 0.0001 compared with healthy subjects; INR 2.0-4.5). Despite an INR greater than 2.0, accompanying heparinization was terminated on day 9. In two stented patients a minor bleeding complication arose after the removal of the arterial catheter. Subacute thrombotic occlusions were not observed. Since F 1 + 2 concentrations did not exceed the upper limit of normal range (1.11 nm/l) in any of the 19 patients, the therapeutic regimen was not changed. Monitoring F 1 + 2 may thus be helpful in introducing a more individual treatment if aggressive anticoagulation has to be performed.

Administration, Oral↗