Asp68His mutation in the A1 domain of human factor V causes impaired secretion and ineffective translocation

Congenital factor V (FV) deficiency is a rare inherited disorder. We determined the mechanism of a missense mutation, Asp68His, in the A1 domain of the FV protein, is associated with severe FV deficiency. We characterized the mutant FV-Asp68His protein using in vitro expression studies by using specific secretion and degradation pathway inhibitors and analysed the intracellular translocation of the mutant protein by immunofluorescence staining. The Asp68His mutation caused very low levels of FV protein in the conditioned media, with normal specific FV activity. Similar mRNA degradation rates between FV-wild-type (wt) and FV-Asp68His mRNA showed that the Asp68His mutation does not affect FV expression at the transcriptional level. A specific secretion pathway inhibitor, brefeldin A, was used to demonstrate that the lower efficiency of transport to the outside of the cell for FV-Asp68His mutant protein compared with that of the FV-wt protein. Furthermore, we showed that the Asp68His mutation resulted in increased intracellular degradation through a MG132-mediated proteasomal degradation pathway. In the transfected cell lysates, FV-wt protein had multiple posttranslational modified forms, but the FV-Asp68His protein was not completely glycosylated. We further observed that the FV-Asp68His protein was retrieved in the endoplasmic reticulum only and did not undergo transport to the Golgi apparatus, leading to impaired secretion. These results strongly suggest that the Asp68His mutation may result in intracellular defective trafficking and enhanced degradation, and impaired secretion of FV protein.

Abstract P5-14-07: Comparison of infectious complications between breast conserving therapy with catheter-based accelerated partial irradiation and whole breast irradiation

Standard treatment after breast conserving surgery (BCS) has been whole breast irradiation (WBI), however, accelerated partial breast irradiation (APBI) has recently been shown to be an alternative in a select group of patients. APBI has been associated with early postoperative as well as delayed infections. In the current study, we compared rates of infectious complications between patients treated with catheter-based APBI and WBI.

Patients were identified from a single-institution prospective registry from 2009 to 2011. Selection criteria included patients who underwent BCT with either single-entry APBI or WBI and fulfilled criteria for ABPI including ≥50 years, tumor size ≤ 3cm, pN0, and no lympho-vascular invasion. Data regarding treatment, patient comorbidities, and outcomes were obtained. Infectious complications were assessed from the date of APBI catheter insertion or from the date of surgery to start of WBI. Infectious complications were classified as early (≤ 30 days) or delayed (> 30 days). Fisher's exact test was used to compare the rate of infection between APBI and WBI.

91 patients were treated with single-entry catheter-based APBI and 267 patients were treated with WBI. Median follow-up time was 76.2 weeks for APBI patients and 115 weeks for WBI patients. Re-excision was required in 20 patients (21.7%) who underwent APBI and in 51 patients (19.1%) who underwent WBI. Overall, infection occurred in 13 patients (14.1%) who underwent APBI versus 39 patients (14.6%) who underwent WBI. In the APBI group, three (3.3%) patients had infection within 30 days and 10 (10.9%) had infection more than 30 days after catheter insertion. 24 (9.0%) patients had infections within 30 days after surgery and 15 (5.6%) patients occurred more than 30 days after surgery in the WBI group. Patients began WBI within an average of 84 days after surgery. In the APBI group, 4 patients required hospital admission, 5 patients had percutaneous aspiration, and one needed incision and drainage. 8 patients were managed with outpatient oral antibiotics. In the WBI group, 5 patients required hospital admission, 13 patients had percutaneous aspiration, and 30 patients were managed with outpatient oral antibiotics. Diabetes, smoking, and BMI >25 were factors commonly associated with infectious complications in both APBI and WBI but not statistically significant (P = 0.6, 0.09, 0.1. respectively).

In contrast to other studies showing that patients treated with catheter-based APBI have higher rates of infection than patients treated with WBI, our study found no statistically significant difference in infection rates between the two groups. A majority of infections following APBI or WBI can be medically managed as an outpatient basis.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-14-07.

Reproductive factors and risks of biliary tract cancers and stones: a population-based study in Shanghai, China

BACKGROUND

Parity has been linked to gallbladder cancer and gallstones, but the effects of other reproductive factors are less clear.

METHODS

We examined 361 incident biliary tract cancer cases, 647 biliary stone cases, and 586 healthy women in a population-based study in Shanghai.

RESULTS

The effects of parity (odds ratios, OR(> or =3 vs 1 child)=2.0, 95% confidence interval (CI) 0.7-5.1), younger age at first birth (OR(per 1-year decrease)=1.2, 95% CI 0.99-1.6), and older age at menarche (OR(per 1-year increase)=1.4, 95% CI 1.1-1.8) on gallbladder cancer risk were more pronounced among women with stones, but the interactions were not significant.

CONCLUSION

Our results provide support for high parity, younger age at first birth, and late age at menarche in the development of gallbladder cancer, particularly among women with biliary stones.

Body size and the risk of biliary tract cancer: a population-based study in China

Though obesity is an established risk factor for gall bladder cancer, its role in cancers of the extrahepatic bile ducts and ampulla of Vater is less clear, as also is the role of abdominal obesity. In a population-based case–control study of biliary tract cancer in Shanghai, China, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for biliary tract cancer in relation to anthropometric measures, including body mass index (BMI) at various ages and waist-to-hip ratio (WHR), adjusting for age, sex, and education. The study included 627 patients with biliary tract cancer (368 gall bladder, 191 bile duct, 68 ampulla of Vater) and 959 healthy subjects randomly selected from the population. A higher BMI at all ages, including early adulthood (ages 20–29 years), and a greater WHR were associated with an increased risk of gall bladder cancer. A high usual adult BMI (⩾25) was associated with a 1.6-fold risk of gall bladder cancer (95% CI 1.2–2.1, P for trend <0.001). Among subjects without gallstones, BMI was also positively associated with gall bladder cancer risk. Regardless of BMI levels, increasing WHR was associated with an excess risk of gall bladder cancer risk, with those having a high BMI (⩾25) and a high WHR (>0.90) having the highest risk of gall bladder cancer (OR=12.6, 95% CI 4.8–33.2), relative to those with a low BMI and WHR. We found no clear risk patterns for cancers of the bile duct and ampulla of Vater. These results suggest that both overall and abdominal obesity, including obesity in early adulthood, are associated with an increased risk of gall bladder cancer. The increasing prevalence of obesity and cholesterol stones in Shanghai seems at least partly responsible for the rising incidence of gall bladder cancer in Shanghai.

Comparison of hypoplastic myelodysplastic syndrome (MDS) with normo-/hypercellular MDS by International Prognostic Scoring System, cytogenetic and genetic studies

The differences in clinical features and prognosis between hypoplastic myelodysplastic syndrome (h-MDS) and normo-/hypercellular MDS (NH-MDS) remain unsettled. In this study, the characteristics of 37 h-MDS patients and 152 NH-MDS patients were compared. Peripheral-blood white blood cell counts and bone marrow blast percentage were lower in h-MDS patients than in NH-MDS patients (P=0.012 and 0.016, respectively). Refractory anemia (RA) was predominant (56.8%) in h-MDS, whereas RA with excess of blast (RAEB) was most common (44.7%) in NH-MDS. Chromosomal abnormalities -7/7q- occurred less frequently in h-MDS patients than in NH-MDS patients (0 vs 18.3%, P=0.022). There was no significant difference in the prevalence of mutations of RAS, AML1, JAK2, PTPN11, FLT3/ITD, and hypermethylation of SOCS1 and SHP1 between these two groups. International Prognostic Scoring System (IPSS) was ideal for predicting prognoses in h-MDS patients (P=0.002). In low- or intermediate-1 (Int-1)-risk MDS patients, h-MDS patients had a superior survival than NH-MDS patients (P=0.01). In conclusion, distinct from NH-MDS, h-MDS patients have different patterns of hemogram, distribution of French-American-British subtypes, cytogenetic changes and prognoses. IPSS is applicable in h-MDS as in NH-MDS. In patients with low- or Int-1-risk MDS, h-MDS patients have a better prognosis than NH-MDS patients.

Clinical significance of cytogenetics and interphase fluorescence in situ hybridization analysis in newly diagnosed multiple myeloma in Taiwan

BACKGROUND

The incidence of multiple myeloma (MM) is lower in Asia than in Western countries. However, it is not known whether cytogenetic abnormalities (CA) characteristic of MM in Asia differ from those documented in the West.

PATIENTS AND METHODS

We analyzed CA by conventional cytogenetics (CG) and/or fluorescence in situ hybridization (FISH), assessed their clinical significance in 150 Chinese MM patients and compared our data with that derived from Western countries.

RESULTS

CA were detected by CG (CG_CA) in 44 (29.3%) of the 150 patients and by FISH (FISH_CA) in 59 (67%) of the 88 patients studied. Presence of either CG_CA or FISH_CA was associated with a poor prognosis. Patients with CG_CA and hyperdiploid chromosomes, always associated with several trisomies, had a longer survival (median 25 months versus 12 months; P=0.025) in comparison with those with non-hyperdiploid chromosomes, usually associated with a monosomy 13/partial deletion of 13q (Delta13) and a rearrangement of 14q32. A novel recurrent CG_CA, add(19)(p13), was found in four patients: all males with immunoglobulin G/lambda isotypes, extramedullary myeloma at diagnosis and a poor prognosis. Three groups of patients with significantly different survival, CG_Delta13, FISH_Delta13 but without CG_Delta13, and neither CG_Delta13 nor FISH_Delta13 (median 9 versus 15 versus 32 months; P=0.013) were identified.

CONCLUSIONS

We conclude that MM CA in our patients are similar to those noted in Western countries, and that combined CG and FISH analysis can predict prognosis. The clinical significance of add(19)(p13) needs to be further investigated.

Hepatosplenic fungal infection in patients with acute leukemia in Taiwan: incidence, treatment, and prognosis

Nosocomial fungal infection increases gradually and has become the leading pathogen at National Taiwan University Hospital since 1993. From January 1995 through May 2002, hepatosplenic fungal infection (HSF) was diagnosed in 37 (7.4%) of the 500 adult patients with acute leukemia who received chemotherapy at this hospital. There was no significant difference in the incidence of HSF between the patients with acute myeloid leukemia and those with acute lymphoblastic leukemia, or between the patients treated with high-dose chemotherapy and those with conventional or low-dose chemotherapy. Candida tropicalis was the leading pathogen, followed by Candida albicans. The computed tomography scan showed multiple hypodense lesions in the liver (89%), spleen (70%), and kidney (27%). Eighteen patients were initially treated with fluconazole and 19 with amphotericin B. Nineteen patients received the planned chemotherapy after the diagnosis of HSF. Among them, eight patients underwent hematopoietic stem cell transplantation and seven patients survived more than 100 days post-transplantation; none of these patients had relapse of prior HSF. Twenty-three patients (62%) died during a median follow up of 10 months, but only seven died due to HSF. In conclusion, a substantial percentage of patients with acute leukemia acquired HSF after chemotherapy and carried high mortality. However, HSF itself is not a contraindication for subsequent chemotherapy and hematopoietic stem cell transplantation.

Clinical and biological implications of partial tandem duplication of the MLL gene in acute myeloid leukemia without chromosomal abnormalities at 11q23

The clinical and biological features of acute myeloid leukemia (AML) with 11q23/MLL translocations are well known, but the characteristics of AML with partial tandem duplication of the MLL gene have not been explored comprehensively. In this study, MLL duplication was analyzed, in 81 AML patients without chromosomal abnormalities at 11q23, using Southern blotting, genomic DNA polymerase chain reaction (PCR), reverse-transcription PCR and complementary DNA sequencing. Nine patients showed partial tandem duplication of the MLL gene, including eight (12%) of the 68 with normal karyotype. Seven patients showed fusion of exon 6/exon 2 (e6/e2), one, combination of differentially spliced transcripts e7/e2 and e6/e2, and the remaining one, combination of e8/e2 and e7/e2. Among the patients with normal karyotype, children aged 1 to 15 showed a trend to higher frequency of MLL duplication than other patients (2/5 or 40% vs 6/62 or 10%, P = 0.102). The patients with tandem duplication of the MLL gene had a significantly higher incidence of CD11b expression on leukemic cells than did those without in the subgroup of patients with normal karyotype (75% vs 28%, P = 0.017). There were no significant differences in the expression of lymphoid antigens or other myeloid antigens between the two groups of patients. In adults, the patients with MLL duplication had a shorter median survival time than those without (4.5 months vs 12 months, P = 0.036). In conclusion, partial tandem duplication of the MLL gene is associated with increased expression of CD11b on leukemic blasts and implicates poor prognosis in adult AML patients. The higher frequency of MLL duplication in children older than 1 year, than in other age groups, needs to be confirmed by further studies.

Epitope mapping of factor VIII inhibitor antibodies of Chinese origin

Epitopes recognized by factor VIII (FVIII) inhibitors of Chinese origin were analysed by immunoblotting with full-length recombinant FVIII (rFVIII), thrombin-activated FVIII (FVIIIa) and 16 FVIII fusion proteins synthesized by bacteria. Twenty-eight patients, 12 with haemophilia A and 16 with autoimmune diseases, were recruited. Antibodies from 22 patients showed reactivity with rFVIII, 20 with FVIIIa, and one reacted only with FVIII fusion proteins. Of these 22 cases, most were reactive with A2-a2 and A3-C1-C2 of FVIII(a). Of the nine cases that depicted binding to the fusion proteins, three were reactive with the A domains, three with only the B domain, and the other three with both the A and B (or C) domains. An epitope for a neutralizing antibody of a haemophilia A patient, designated TWN-112, was localized to residues 323-390, specified by FVIII fusion proteins. The same epitope also appeared on an FVIII-expression phage library screening. Immunoabsorption of antibodies from TWN-112 with the epitope reduced the neutralizing activity of the inhibitor by 33%. The incidence of a1 of FVIII is higher, and that of a3 is lower, than previously reported. Two novel epitopes, reported for the first time in this paper, were localized on the 8B2 (amino acid residues 1022-1204) and 8A2(V) (residues 673-740) fusion proteins. These two epitopes were able to reduce inhibitory antibody activity by 24% and 25% respectively. Changes of FVIII fragment specificity were also observed in one of six patients for whom multiple samples, collected at different times, were available. Our initial finding showed that the FVIII inhibitors in these Chinese patients shared epitopes with those of patients from very different genetic backgrounds, suggesting a common mechanism for the development of FVIII inhibitors.

Beta-catenin mutations in biliary tract cancers: a population-based study in China

beta-Catenin is an ubiquitously expressed cytoplasmic protein that has a crucial role in both cadherin-mediated cell-cell adhesion and as a downstream signaling molecule in the wingless/Wnt pathway. Activating mutations in exon 3 of the beta-catenin gene, at the phosphorylation sites for ubiquitination and degradation of beta-catenin, are present in a variety of cancers. Because alterations of the adenomatous polyposis coli (APC) gene are present in biliary tract cancers and the APC protein modulates levels of beta-catenin, we evaluated the role of beta-catenin in biliary tract cancer by sequencing the third exon of the beta-catenin gene among 107 biliary tract cancers and 7 gallbladder adenomas from a population-based study in CHINA: Point mutations of serine or threonine phosphorylation sites in exon 3 of beta-catenin were present in 8 of 107 (7.5%) biliary tract cancers and 4 of 7 (57.1%) gallbladder adenomas. Mutations of beta-catenin were more frequent in ampullary and gallbladder carcinomas than in bile duct carcinomas (P = 0.04) and in papillary adenocarcinomas than other histological types of carcinomas (P = 0.02). These results suggest that the molecular pathways of biliary tract neoplasms vary by anatomical subsite and histological subtype.

Domain specific monoclonal anti-factor VIII antibodies generated by inclusion body-renatured factor VIII peptides

Production of monoclonal anti-factor VIII (FVIII) antibodies was hampered by the availability of FVIII proteins devoid of albumin and the von Willebrand factor (vWF). We showed a successful way to generate domain specific anti-FVIII antibodies by using a series of Escherichia coli expressed FVIII fusion peptides. A total of eight fusion peptides were synthesized to cover almost the entire coding region of FVIII. All except one of the fusion peptides were insoluble and became aggregated as inclusion bodies. Purification and refolding of the peptides were accomplished by solublizing them with denaturants and dialyzing them in appropriate buffers, this being followed by chromatography of the refolded fractions on a metal-ion chelating column. These purified FVIII fusion peptides were used individually or as a pool to immunize mice and generate antibodies. Three monoclonal antibodies, D2, E6 and B12, were obtained. D2 recognizes a region (residues 1680-1703) of the light chain of FVIII, E6 recognizes a fragment (residues 744-1021) in the heavy chain, and B12, the A1 domain (residues 89-326). Both D2 and B12 inhibited >80% FVIII function. The affinities (k(A)) of the antibodies for FVIII were 1.62x10(7) M(-1) for D2 and 2.2x10(8) M(-1) for E6. Although B12 is inhibitory, it did not show a strong binding affinity with FVIII. The specificity of D2 and E6 for FVIII was demonstrated by immunoprecipitation of the FVIII protein in full-length recombinant FVIII (rFVIII) supplemented FVIII-deficient plasma, but not in FVIII-deficient plasma alone. An enzyme-linked immunosorbant assay (ELISA) using D2 or E6 was designed to detect plasma FVIII. The system may be useful in monitoring FVIII in cultured supernatants and in mouse models for gene therapy experiments.

Novel mutations in the Factor VII gene of Taiwanese Factor VII-deficient patients

The genetic defects of four Taiwanese patients with factor VII (FVII) deficiency were studied. FVII activity and antigen levels were < 1 u/dl and 125.7 u/dl (patient I), < 1 u/dl and < 1 u/dl (patient II), 3.4 u/dl and 5.9 u/dl (patient III), and 1.2 u/dl and 30.4 u/dl (patient IV) respectively. The 5' flanking region, and all exons and junctions were amplified using polymerase chain reaction and sequenced. Patient I was homozygous for a 10824C-->A transversion with Pro303-->Thr mutation in exon 8. In patient II, a heterozygous transversion, 9007+1G-->T at the IVS6, a heterozygous decanucleotide insertion polymorphism at -323 (both mutations present in his father) and a heterozygous deletion, del TC (26-27) in exon 1A (originating from his mother) were identified. Patient III had a homozygous 10961T-->G transversion with His348-->Gln mutation in exon 8. Patient IV had a heterozygous 10902T-->G transversion with Cys329-->Gly mutation in exon 8 (transmitted to her second son) and a heterozygous decanucleotide insertion polymorphism at -323 (transmitted to her third son). All but one of the FVII gene mutations detected in the four patients have not been previously reported. In conclusion, four novel mutations of the FVII gene in Taiwanese, including two missense mutations in exon 8, one point mutation at the exon 6 splice site and one deletion in exon 1A, were identified.

Factor V Arg306 --> Gly mutation is not associated with activated protein C resistance and is rare in Taiwanese Chinese

Polymerase chain reaction amplification followed by BstOI enzyme digestion and DNA sequencing was employed to detect the mutation of factor V gene. The subjects consisted of 105 venous thrombophilic patients and 183 healthy controls. Only one patient was found to have factor V Arg306 --> Gly mutation, his elder son also had an identical mutation. None of the healthy subjects studied had Arg306 --> Thr mutation. The rare event of factor V Arg306 --> Gly mutation in patients and controls suggest that this mutation is not associated with increased risk of venous thrombosis. Conventional, modified and extended activated protein C (APC) resistance assays in this patient and his family members clearly showed that factor V Arg306 --> Gly mutation is not associated with APC resistance (APC sensitivity ratio <2). In conclusion, factor V Arg306 --> Gly mutation is rare in Taiwanese Chinese and not associated with APC resistance, it is possibly not a risk factor for venous thrombophilic thrombosis.

Methylation of the p15(INK4B) gene in myelodysplastic syndrome: it can be detected early at diagnosis or during disease progression and is highly associated with leukaemic transformation

To investigate the time sequence of occurrence of p15(INK4B) gene methylation in myelodysplastic syndrome (MDS) and its correlation with leukaemic transformation and survival of patients, the methylation status of the p15(INK4B) promoter region was analysed in 50 patients and was serially studied in 22 of them. Of the 50 patients, 17 (34%) showed p15(INK4B) gene methylation, first demonstrated at diagnosis or during follow-up. When FAB subtypes at the time of study were used in the analysis, the incidence of (p15INK4B) methylation in each risk group of MDS remained stable throughout the course: 0% for low-risk MDS [refractory anaemia (RA) and RA with ring sideroblasts] and from 23% at diagnosis to 30% for high-risk MDS [RA with excess of blasts (RAEB), RAEB in transformation and chronic myelomonocytic leukaemia] respectively. The incidence of p15(INK4B) methylation rose to 60% at initial study and, finally, to 75% in cases of acute myeloid leukaemia (AML) evolved from MDS. Most patients (69%) with p15(INK4B) methylation showed disease progression to AML; it could be detected before, at the time or after the diagnosis of leukaemic transformation. p15(INK4B) methylation in MDS patients implicated a shorter survival time in univariate analyses, but its prognostic significance disappeared in multivariate analyses. In conclusion, p15(INK4B) methylation can be detected early at the diagnosis of MDS or acquired during disease progression. It may play an important role in the pathogenesis of some high-risk MDS and is related to leukaemic transformation of MDS.

Identification of a new CA dinucleotide repeat in the human factor VIII gene

We describe the identification of a new CA dinucleotide repeat marker for the diagnosis of haemophilia A carriers. The marker (CA-6) is present in intron 6 as a single copy 5 kb upstream of exon 7. Of 195 and 118 X chromosomes from normal individuals and haemophilia A patients, respectively, we observed three alleles of CA-6 with 12-14 repetitions [(CA)(12-14)]. The frequencies were 0.5% and 0% for (CA)(12), 99% and 95.8% for (CA)(13), and 0.5% and 4.2% for (CA)(14) in normals and patients respectively. We conclude that the low polymorphism of the CA-6 marker renders it less useful for the diagnosis of Chinese haemophilia A carriers.

Hemophilia B with mutations at glycine-48 of factor IX exhibited delayed activation by the factor VIIa-tissue factor complex

Gly-48 is in the conserved DGDQC sequence (residues 47-51 of human factor IX) of the first EGF (EGF-1)-like domain of factor IX. The importance of the Gly-48 is manifested by two hemophilia B patients; factor IXTainan and factor IXMalmo27, with Gly-48 replaced by arginine (designated IXG48R) and valine (IXG48V), respectively. Both patients were CRM+ exhibiting mild hemophilic episodes with 25% (former) and 19% (latter) normal clotting activities. We characterize both factor IX variants to show the roles of Gly-48 and the conservation of the DGDQC sequence in factor IX. Purified plasma and recombinant factor IX variants exhibited approximately 26%-27% normal factor IX's clotting activities with G48R or G48V mutation. Both variants depicted normal quenching of the intrinsic fluorescence by increasing concentrations of calcium ions and Tb3+, indicating that arginine and valine substitution for Gly-48 did not perturb the calcium site in the EGF-1 domain. Activation of both mutants by factor XIa appeared normal. The reduced clotting activity of factors IXG48R and IXG48V was attributed to the failure of both mutants to cleavage factor X: in the presence of only phospholipids and calcium ions, both mutants showed a 4 to approximately 7-fold elevation in Km, and by adding factor VIIIa to the system, although factor VIIIa potentiated the activation of factor X by the mutants factor IXaG48R and factor IXaG48V, a 2 to approximately 3-fold decrease in the catalytic function was observed with the mutant factor IXa's, despite that they bound factor VIIIa on the phospholipid vesicles with only slightly reduced affinity when compared to wild-type factor IXa. The apparent Kd for factor VIIIa binding was 0.83 nM for normal factor IXa, 1.74 nM for IXaG48R and 1.4 nM for IXaG48V. Strikingly, when interaction with the factor VIIa-TF complex was examined, both mutations were barely activated by the VIIa-TF complex and they also showed abnormal interaction with VIIa-TF in bovine thromboplastin-based PT assays. Taken together, our results suggest that mutations at Gly-48 altered the interaction of factor IX with its extrinsic pathway activator (VIIa-TF complex), its macromolecular substrate (factor X), and its cofactor (factor VIIIa).

Protein C and protein S deficiencies are the most important risk factors associated with thrombosis in Chinese venous thrombophilic patients in Taiwan

The relative risks (odds ratio, OR) of various risk factors for venous thrombophilia, including sex, antithrombin III, protein C (PC), protein S (PS) and plasminogen deficiencies, and C677T homozygous mutation of methylenetetrahydrofolate reductase gene were assessed using age matched (+/-5 years) conditional logistic regression analysis in 116 Chinese venous thrombophilic patients (58 males; 58 females; mean age 47.5+/-17.7 [SD] years) and 125 healthy controls (67 males; 58 females; mean age 45.5+/-15.7 years). None of the patients had prothrombin G20210A and factor V Leiden mutation or an activated PC sensitivity ratio of less than 2. One hundred and five age-matched patients and 105 controls were entered in this analysis. Only PC and PS deficiencies were significantly associated with increased risk for the development of thrombosis with an OR of 10.6 and 6.7, respectively. The findings of this study suggest that PC deficiency and PS deficiency are the most important risk factors for thrombosis in Chinese venous thrombophilic patients.

Characterization of acute myeloid leukemia with MLL rearrangements--no increase in the incidence of coexpression of lymphoid-associated antigens on leukemic blasts

MLL gene rearrangements are associated with coexpression of myeloid- and lymphoid-associated antigens on leukemic blasts and a dismal outcome in acute lymphoblastic leukemia (ALL). Whether the same conditions can apply to acute myeloid leukemia (AML) is not quite clear. Rearrangements of the MLL gene were analyzed on 113 patients with newly diagnosed de novo AML in a single institution. Sixteen (14%) of them showed rearranged bands by Southern blot analysis, including three (50%) of six infants, three (14%) of 21 children between 1 and 15 years and 10 (12%) of 86 adults. MLL rearrangements were not only detected in M5 (four of 12 patients, 33%) and M4 (six of 31, 19%) subtypes but also in other non-M4-M5 AML (six of 70, 9%), including M1, M2 and M7, but not M3 subtype. Seven patients had chromosomal abnormalities involving 11q23, but nine did not. The latter comprised three (6%) of 48 patients with normal karyotype, one with t(8;21), none with t(15;17), inv(16) or t(9;22), and four (15%) of 27 with cytogenetic aberrations other than those specific structural abnormalities. In contrast to ALL, AML patients with MLL rearrangements did not tend to coexpress lymphoid- and myeloid-associated antigens simultaneously on leukemic blasts and have similar outcome as those without the gene rearrangements.

The prevalence of C677T mutation in the methylenetetrahydrofolate reductase gene and its association with venous thrombophilia in Taiwanese Chinese

C677T mutation of the methylenetetrahydrofolate reductase gene remains a controversial risk factor for venous thrombosis in Whites. The prevalence of methylenetetrahydrofolate reductase C677T genotype and its association with vascular thrombosis are not well established in Chinese population. We conducted a case-control study to investigate the prevalence of methylenetetrahydrofolate reductase C677T gene mutation and its association with venous thrombophilia in Taiwanese Chinese. The subjects consisted of 112 venous thrombophilic patients and 125 healthy controls, with similar age (p=0.08) and sex (p=0.58). The prevalent rates of C/T heterozygote were 32.8 and 44.6%; whereas those of T/T homozygote were 6.4 and 8.0% in the controls and patients, respectively. Neither C/T heterozygote (odds ratio, 1.7; 95% confidence interval, 1.0-3.0, p=0.05] nor T/T homozygote (odds ratio, 1.4; 95% confidence interval, 0.5-4.0, p=0.5) was significantly associated with venous thrombosis. Even when only subjects (52 patients and 107 controls) with normal inhibitor protein levels were analyzed, the association of T/T homozygote with venous thrombosis remained insignificant (p=0.06) with an odds ratio (95% confidence interval) of 3.4 (0.99-11.7). We concluded that, in Taiwanese Chinese, methylenetetrahydrofolate reductase C677T mutation is a common genetic mutation, but T/T homozygote is not a significant risk factor for venous thrombophilia.

Minimally differentiated acute myeloid leukemia in Taiwan: predominantly occurs in children less than 3 years and adults between 51 and 70 years

Acute myeloid leukemia (AML) with minimal differentiation was usually referred to as acute undifferentiated leukemia in the past. With the help of immunophenotyping, this subtype of leukemia was shown to express myeloid antigens on the blasts and was designated AML-M0 by FAB Cooperative Study Group in 1991. Among the 423 consecutive newly diagnosed de novo AML at our institution, 12 (2.8%) were of M0 subtype. The proportion of M0 in AML was higher in children than in adults (8.2% vs 1.7%). Four other M0 patients referred from outside hospitals for immunophenotyping were also included in this study. There were two peaks in age distribution of these 16 patients: less than 3 years and between 51 and 70 years, respectively. Organomegaly was more common in patients with AML-M0 than in those with other subtypes (56.3% vs 29.2%, P = 0.025). The former patients had higher incidences of CD7 and CD34 expression on the leukemic cells than the latter ones (50% vs 16.9%, P = 0.003 and 69.2% vs 37.9%, P = 0.019, respectively). The patients with AML-M0 showed more frequent clonal chromosomal abnormalities in the leukemic cells than other AML patients (83.3% vs 53.9%, P = 0.039); the same is also true for complex cytogenetic aberrations (50% vs 11. 4%, P = 0.004). Adults with AML-M0 showed a lower complete remission (CR) rate and significantly poorer survival than those with non M0-AML. However there was no significant difference in outcome between the two groups of pediatric patients. In conclusion, AML-M0 is a unique subtype of leukemia that has distinct age distribution and shows different clinical and biological characteristics from other AML. Adult patients have poor prognosis. Whether pediatric patients had better outcome than adults needs to be clarified in further studies.

Extramedullary relapse after all-trans retinoic acid treatment in acute promyelocytic leukemia--the occurrence of retinoic acid syndrome is a risk factor

All-trans retinoic acid (ATRA) is now a standard agent for remission induction of acute promyelocytic leukemia (APL). Recently, extramedullary relapse, which was a rare condition in APL patients after chemotherapy alone, was reported with an increased frequency after ATRA treatment. However, it is not yet clear whether ATRA truly increases the risk of extramedullary recurrence and what are the risk factors. In this study, three of 13 patients with recurrent APL after prior treatment of ATRA were found to have extramedullary involvement, compared with none in 11 recurrent patients previously treated with chemotherapy alone (estimated relative risk 2.100, 95% confidence interval 1.341-3.289). Furthermore, in the former group of patients, the development of retinoic acid (RA) syndrome during prior induction treatment was significantly associated with extramedullary involvement at relapse (three in five patients with RA syndrome vs none in eight without the syndrome, estimated relative risk 5.000, 95% confidence interval 1.448-17.271). In conclusion, ATRA may predispose APL patients to extramedullary involvement at relapse and the occurrence of RA syndrome is a risk factor for it. Further studies are needed to confirm these findings. It also remains to be clarified whether treatment modification is necessary in patients who develop RA syndrome during ATRA treatment.

Engineered recombinant factor VII Q217 variants with altered inhibitor specificities

Recombinant factor VII with residue 217 (chymotrypsinogen numbering system) converted to alanine (VIIQ217A), glutamic acid (VIIQ217E), or glycine (VIIQ217G) was characterized. In a prothrombin time assay, VIIQ217E demonstrated 100%, VIIQ217A 15%, and VIIQ217G <1% clotting activities relative to wild-type VII. Binding of VIIQ217A and VIIQ217G to TF was comparable to that of wild-type VII to TF. All the variants were readily activated by factor Xa. Autoactivation in the presence of TF was efficient with VIIQ217E, slow with VIIQ217A, but undetected with VIIQ217G. Relative to wild-type VII added at the same concentration, VIIQ217E had no effect on the PT of normal plasma, whereas VIIQ217A slightly and VIIQ217G dramatically prolonged the clotting time in a dose-dependent manner. Activation of macromolecular substrates paralleled this functional inhibition. The k(cat)/K(M) values for factor X activation in the presence of TF were 2.4 for VIIaQ217E as compared to 1.9 (M(-)(1) s(-)(1) x 10(7)) for wild-type VIIa, 1.57 for VIIaQ217A, and 0.05 with VIIaQ217G. In comparison to wild-type VIIa, VIIaQ217E cleaved the chromogenic substrate S2765 (Z-D-Arg-Gly-Arg-pNA) with 10-fold higher k(cat). Analysis of the interactions with the inhibitors TFPI and antithrombin III demonstrated that VIIaQ217A but not VIIaQ217E or VIIaQ217G was inhibited less efficiently by TFPI either in the presence or in the absence of factor Xa. In contrast, VIIaQ217A association with antithrombin III in the presence of heparin was the fastest among the variants with a second-order rate constant of 2.31 (x10(3) M(-)(1) min(-)(1)), as compared to 0.47 and 1.47 for VIIaQ217E and wild-type VIIa, respectively. Our results demonstrate that residue Q(217) is important in regulating substrate and, more importantly, inhibitor recognition by VIIa.

Trace analysis of ethosuximide in human plasma with a chemically removable derivatizing reagent and high-performance liquid chromatography

A simple and sensitive liquid chromatographic method is described for the determination of ethosuximide in human plasma, as a highly sensitive derivative. Ethosuximide spiked in plasma was extracted with toluene and derivatized with a chemically removable derivatizing reagent, 2-(2-naphthoxy)ethyl 2-[1-(4-benzyl)piperazyl]ethanesulfonate, in a homogeneous system, using magnesium oxide as base catalyst. The resulting derivative was separated on a LiChrospher diol column with 1.2% isopropanol in n-hexane as the mobile phase and using coumarin as the internal standard. Several parameters affecting the extraction/derivatization of ethosuximide from spiked plasma were investigated. The linear range for the determination of ethosuximide in spiked plasma was over 30-700 nmol/ml. For ethosuximide in plasma, the detection limit (signal-to-noise ratio=3; sample size, 10 microl) was about 9 pmol; the relative standard deviation was 6.4% for intra-day assay (n=6) and 9.2% for inter-day assay (n=6) and the relative recovery was found greater than 94%.

Clonal disease of natural killer large granular lymphocytes in Taiwan

Lymphoproliferative diseases of large granular lymphocytes (LDGL) may arise from either CD3+ T cells or CD3- natural killer (NK) cells. LDGL with clonal proliferation of large granular lymphocytes (LGL) is defined as LGL leukaemia. The number of patients with NK-LGL leukaemia reported is limited and the pathogenesis of the disease is not yet clear. From 1991 to 1998 six patients with cytogenetically proved clonal disease of NK-LGL were identified in our institute. All were seropositive for Epstein-Barr virus (EBV). EBV RNA or DNA could be detected in LGL from four patients by EBV in situ hybridization or Southern blot analysis. Most patients ran an aggressive clinical course and five died of the disease. Nonrandom clonal chromosomal abnormalities, including duplication of 1q, rearrangement at 3q and loss of chromosomes Y, 13 or 10, were noted in the six patients from this study and in eight from the literature. The implications of these recurrent cytogenetic aberrations in the development and progression of the disease deserve further studies.

Acute and chronic arsenic poisoning associated with treatment of acute promyelocytic leukaemia

Seven relapsed and/or refractory acute promyelocytic leukaemia patients were treated by arsenic trioxide (As2O3). Four patients (4/7, 57%) achieved complete remission after one to three cycles of treatment and the most common acute side-effect was fluid retention (in six patients, 86%), including weight gains and pleuro-pericardial effusions. Evident polyneuropathy compatible with chronic arsenic toxicity was noted in two of the three patients who received As2O3 maintenance therapy and one of them had marked distal muscular atrophy. We suggest that As2O3 may be a useful salvage therapy for relapsed and refractory APL patients, but the acute or chronic arsenic toxicity should be carefully monitored.

Aetiologies and prognosis of Chinese patients with deep vein thrombosis of the lower extremities

Deep vein thrombosis (DVT) of the lower extremities is not frequently encountered in Oriental patients. We investigated its aetiology and prognosis in 143 patients (65 males, 78 females), presenting to the National Taiwan University Hospital over 4.3 years, diagnosed by colour Doppler ultrasonography. Swelling and pain of the lower extremities were the most frequent presenting symptoms. The left femoropopliteal veins were more frequently involved than other parts of the lower extremities. In these patients, malignancy with or without intravenous catheterization was the most frequent cause (39 patients, 27%). Other common aetiologies included coagulopathy (29 patients, 20%), immobilization (24 patients, 17%) and catheter-related (13 patients, 9%). No definite aetiology could be determined in 37 patients (26%). During follow-up, 27 patients (19%) died, mostly with malignancy. Pulmonary embolism was noted in 16 patients and was not significantly directly related to death. Compared to similar studies in Caucasian patients, there were significant differences in the aetiology of DVT, with malignancy and coagulopathy more common in these Chinese patients.

Human immunodeficiency virus infection in haemophiliacs in Taiwan: the importance of CD4 lymphocyte count in the progression to acquired immunodeficiency syndrome

From July 1984 to December 1996, we tested and studied 303 haemophilic patients for the infection of the human immunodeficiency virus (HIV). Among the 261 haemophilia A patients 44 were HIV positive (16.9%), while none of the haemophilia B patients was HIV positive. The mean age of the 44 HIV-seropositive patients in 1984 was 20.6 years (2-37 years). Seven who had known seroconversion dates and 29 whose first seropositive dates were known seroconverted before 1986. Acquired immunodeficiency syndrome (AIDS) has developed in 16 patients, nine of whom presented with Pneumocystis carinii pneumonia, three with tuberculosis infection, and 13 had died. The Kaplan-Meier estimate of the progression rate to AIDS after the date of first seropositive test is about 30% at the 10th year. The median survival time after development of AIDS obtained from the Kaplan-Meier estimate of the survival curve was 11.7 months. Statistical analysis for the covariate effects on the risk of developing AIDS by the Cox proportional hazards model revealed that there was a statistically significant negative association of the risk for progression to AIDS with the logarithm of initial CD4 cell counts (P = 0.027) and the rate of decline of CD4 cell counts (P = 0.040), but not with age (P = 0.650). In conclusion, the clinical characteristics of AIDS haemophiliacs in Taiwan were not different from that observed in western countries. Low initial CD4 cell count and sharp decline in CD4 cell counts, but not age, increased the risk of progression to AIDS.

Familial macrothrombocytopenia with granulocyte inclusion: a clinical and laboratory problem

The differential diagnosis of familial macrothrombocytopenia and idiopathic thrombocytopenic purpura (ITP) may be difficult owing to the similarities in their clinical and laboratory presentations, but it is important because of dissimilarities in their management and prognosis. We investigated two families with familial macrothrombocytopenia and granulocyte inclusion. The probands of both families presented with mild bleeding tendency, macrothrombocytopenia, normal bone marrow, and increased percentages of platelet-associated immunoglobulin G (IgG) and reticulated platelets. ITP had been misdiagnosed in both patients initially. Both probands failed to respond to steroid therapy. Family study revealed an autosomal dominant pattern of heredity in both families, with absence of Alport's syndrome-like features (hearing impairment, congenital cataract, and interstitial nephritis). All thrombocytopenic family members showed blue cytoplasmic inclusions in neutrophils on peripheral blood smears. Ultrastructurally, distinct granulocyte inclusions comprising clusters of rough endoplasmic reticulum, smooth endoplasmic reticulum, and polysomes were detected, without the presence of parallel filaments. The clinical, laboratory, and hereditary findings were consistent with a diagnosis of Sebastian platelet syndrome in both families. In conclusion, caution should be exercised when interpreting the percentages of platelet-associated IgG in thrombocytopenic patients, as overinterpretation may lead to misdiagnosis of macrothrombocytopenia as ITP. Family history is important, as familial ITP is rare, and careful examination of blood smears is essential.

A longitudinal study of immunological status in Chinese haemophiliacs: importance of the heat viral inactivation of factor concentrates. II. Improvements of CD4/CD8 ratio after treatments with heat-inactivated factor concentrates

Screened and heated clotting factor concentrates of intermediate purity have been used in Taiwanese haemophiliacs since the end of 1986. A significant improvement of CD4/CD8 ratio during the years 1987-1989 as compared with those during the years 1984-1986 was observed in haemophilia A patients [mean +/- SD (median), 1.191 +/- 0.495 (1.163) vs. 0.880 +/- 0.325 (0.838), P = 0.0020] who were seronegative for human immunodeficiency virus. Almost all patients received an increased amount of factor VIII concentrates and total plasma products since 1987. Multiple linear regression analysis for the association of CD4/CD8 ratio with changes in dosage of plasma products revealed that there was a significant positive association of CD4/CD8 ratio measured during 1987-1989 with dosage of factor VIII concentrate administered during 1984-1986 (P = 0.0230), which is an indicator for changes in viral load, but not with changes in dosage of plasma products, which are indicators for changes in plasma protein intake. Our data indicate that immunological abnormalities after replacement therapy observed in haemophiliacs are mainly attributed to virus infection through infusion of factor concentrates, not to allogeneic proteins existing in plasma products.

High prevalence of antithrombin III, protein C and protein S deficiency, but no factor V Leiden mutation in venous thrombophilic Chinese patients in Taiwan

We studied the prevalence of antithrombin III (AT III), protein C (PC) and protein S (PS) deficiencies and factor V Leiden mutation in thrombophilia in Taiwan. Eighty-five consecutive and unrelated patients with otherwise unexplained venous thrombophilia were studied. Both antigen and activity of inhibitors were determined using commercial kits (Stago), activated PC sensitivity ratio (APC SR) by Coatest (Chromogenix), and factor V mutation by polymerase chain reaction with sequence specific primer. Of 85 patients, 41 were male, 44 female, and mean age 49.4 years (17-82 years). None had factor V mutation, or APC SR of less than 2; 50 (58.8%) showed a deficiency of inhibitor proteins; 34 (68.0%) were hereditary, 16 (32.0%) non-hereditary; 3 had an AT III deficiency, 16 a PC deficiency, 28 a PS deficiency, and 3 a combined deficiency. Thirty-five were non-deficient without a known cause. The average age at the first thrombotic episode was 48.5 years (13-81 years). Thrombosis occurred spontaneously in 39 (78.0%) of 50 deficient patients. In conclusion, a relatively higher prevalence of AT III, PC and PS deficiency (59%), but no factor V Leiden mutation, was found in venous thrombophilic Chinese patients in Taiwan compared to that in western countries. Screening for inhibitor protein deficiency in Chinese thrombophilic patients is highly recommended.

Clinical and biological characteristics of acute promyelocytic leukemia in Taiwan: a high relapse rate in patients with high initial and peak white blood cell counts during all-trans retinoic acid treatment

Acute promyelocytic leukemia (APL) patients treated with all-trans retinoic acid (ATRA) and chemotherapy have been shown to have better outcome than those treated with conventional chemotherapy alone. However, the biological characteristics of leukemic cells and their clinical implications in patients treated with ATRA have not been well established. In this study, the biological and clinical features of 30 APL patients were reported. The risk factors for relapse and for occurrence of retinoic acid (RA) syndrome, which might cause morbidity or mortality of patients after ATRA treatment, were also analyzed. All patients showed 15;17 translocation by cytogenetic and/or gene analysis. Patients in this study had higher white blood cell (WBC) counts and a higher incidence of additional abnormalities than those from other areas. The ratio of long (L) form to short (S) form PML-RAR alpha fusion transcript was 1.8:1, a value lower than that of Latino patients but higher than that of Italians. Leukemic cells from four patients showed coexpression of T cell-associated antigen CD2 which was highly correlated with S form fusion transcript. Nine (36%) of the 25 patients treated with ATRA developed RA syndrome; all but one were successfully controlled by corticosteroid. Complete remission (CR) rate was 84%. Patients with high WBC counts tended to develop RA syndrome and had increased risk of relapse. Isochromosome for the long arm of the derivative chromosome 17, ider(17q), as an additional chromosomal abnormality was also associated with poor outcome in this study. In conclusion, APL in this study showed some different biological characteristics compared with those reported in other areas. High WBC count was a risk factor for relapse and development of RA syndrome after ATRA treatment. The prognostic implication of the presence of ider(17q) needs further clarification.

Prognostic significance of immunophenotypes in adult lymphoblastic lymphomas

Adult lymphoblastic lymphoma (LBL) can be of T-cell or B-cell lineage. However, the clinical significance of immunophenotypes is largely unknown. We conducted a retrospective study to compare T-cell LBL with its B-cell counterpart. Between 1983 and 1995, 50 adult patients were diagnosed as LBL at National Taiwan University Hospital. Twenty-seven patients (T-LBL:20 and B-LBL:7) had adequate clinical information and formed the basis of final analysis. Pertinent characteristics, including sex, age, and lymphoma stages of these two groups of patients were identical. Detailed clinical features were compared. Systemic involvements of lymphoma were similar except that T-cell LBL had significantly more mediastinal involvement (T:B = 70%:14.3%, p = 0.011). CNS involvement was high in both groups (T:B = 50%:28.6%, p = NS). B-cell LBL had a better overall survival than T-cell LBL, although the survival benefit became less significant after 30 months. The median survival of T- and B-cell LBL was 8 and 31 months, respectively. Both groups taken together, patients who had received prophylactic cranial irradiation had a better overall survival (p < 0.01). We suggest that: a) B-cell LBL has a relatively favorable prognosis than T-cell LBL, at least in the initial 2 to 3 years; b) except for mediastinal involvement, the clinical presentation of T- and B-cell LBL appears to be similar; c) treatment policy, such as the need of prophylactic cranial irradiation, of these two groups may also be similar.

PIG-A gene mutations in four Taiwanese patients with paroxysmal nocturnal haemoglobinuria following aplastic anaemia

Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired haemolytic disorder caused by deficient biosynthesis of the glycosyl phosphatidylinositol (GPI) anchor in haemopoietic stem cells. PIG-A, an X-linked gene that participates in the first step of GPI-anchor synthesis, is responsible for PNH. Various abnormalities of the PIG-A gene have been demonstrated in all patients with PNH so far examined. In this study we characterized the somatic mutations in PIG-A gene in four Taiwanese patients with PNH. We identified five novel mutations in the PIG-A gene, three single nucleotide substitution mutations (-342, C-->G, codon 335, GGT-->AGT and codon 405, GCT-->GTT) and two frameshift mutations (codon 22, GGA-->G-A and codon 356, TGT-->TGTT) in the PIG-A gene. The -342 mutation was judged to be a polymorphism. Furthermore, three patients had previous clinicopathologic evidence which suggested aplastic anaemia (AA), before the development of PNH. One of these was found to have thrombocytopenia during follow-up. We suggest that the somatic PIG-A gene mutations highlight a subgroup of AA having a pathogenetic link with PNH.

Synergistic transactivation of HNF-1alpha, HNF-3, and NF-I contributes to the activation of the liver-specific protein C gene

We have previously characterized the functional cis elements of the protein C promoter. One hepatocyte nuclear factor-1 (HNF-1) site, three HNF-3 sites, and at least two NF-I sites have been identified within the 140-bp basal transcriptional unit of this promoter. Here we present evidence that either HNF-1alpha or HNF-3 can cooperate with each other in binding to their cis elements. The results from the co-transfection assays in HeLa cells showed a novel synergistic transactivation between HNF-1alpha and HNF-3. Our data further indicate that the unique overlapping of the HNF-3 sites, the specific spatial relationship of the sites, and the co-activator C/EBP all contributed to the synergistic interaction. Although NF-I itself has a weak transactivating effect, it apparently coordinates the transactivation complex formation. NF-I can synergistically enhance the transactivation of HNF-1alpha or HNF-3. Taken together, the combinatorial interplay of HNF-1alpha, HNF-3, and NF-I make a significant contribution to the activation of the liver-specific protein C gene.

GB virus-C/hepatitis G virus infection in an area endemic for viral hepatitis, chronic liver disease, and liver cancer

BACKGROUND & AIMS

GB virus-C/hepatitis G virus (GBV-C/HGV) is a newly identified flavivirus, and little is known about its clinical significance. GBV-C/HGV was investigated in different populations, and its coinfection was investigated in patients with liver disease in Taiwan where hepatitis B and C are endemic.

METHODS

Viral RNA was studied in 70 high-risk individuals, 20 patients with chronic non-B, non-C hepatitis, 13 with non-A-E fulminant hepatitis, 100 with asymptomatic hepatitis B surface antigen carriage, 120 with hepatitis B surface antigen-positive chronic liver disease and hepatocellular carcinoma, 100 patients with chronic hepatitis C, and 100 healthy adults.

RESULTS

GBV-C/HGV infection was more frequent in high-risk groups (15%-30%) and hepatitis C virus carriers (10%) than in healthy adults (1%) and hepatitis B virus carriers (3.2%). Eighty-three percent of those infected had undergone blood transfusions previously. The prevalence in hepatitis B virus carriers increased with the severity of liver disease, being 1% in asymptomatic carriers and 10% in hepatocellular carcinoma. In chronic hepatitis C, clinical and virological data were comparable between those with and without coinfection.

CONCLUSIONS

In Taiwan, GBV-C/HGV infection is common in high-risk groups, and its coinfection seems to not aggravate the course of chronic hepatitis B or C.

Characterization of human protein C gene promoter: insights from natural human mutants

Human protein C is a liver-produced plasma anticoagulant. Four heterozygous point mutations located in the promoter region have been identified in families with type I protein C deficiency and recurrent venous thrombosis. However, detailed analysis of regulatory elements and their interacting factors remains to be undertaken. This report presents results of biochemical and functional characterizations of several cis-elements located in the 5'-upstream regulatory region and the trans-acting factors that interact with them. A cloned DNA fragment from nucleotides (nt) -418 to +45 could confer tissue specificity, whereas nt -88 to +45 was sufficient for basal promoter activity of protein C gene. Five cis-elements corresponding to HNF-1, HNF-3, and NF-I/CTF binding sites have been identified. Four heterozygous mutations have been shown to disrupt HNF-3 [mutants of A(-32)G and T(-27)A] and HNF-1 [T(-14)C and C(-10)T] binding. Mutation in the NF-I-binding site also significantly impairs the promoter activity. Viewed as a whole, these results indicate that HNF-1, HNF-3, and NF-I/CTF play critical roles in transcriptional regulation of the protein C gene.

Clinical and hematological characteristics of hepatosplenic T gamma/delta lymphoma with isochromosome for long arm of chromosome 7

Hepatosplenic T gamma/delta lymphoma is a rare entity of peripheral T cell lymphoma. Three of 386 patients with non-Hodgkin's lymphoma in our institute were found to have this subtype of lymphoma. All had chromosomal abnormalities of isochromosome 7q and trisomy 8. The clinical and hematological features of these three patients are reported. All were males with ages ranging from 23 to 29 years. Initial presentation comprised purpura and variable degree of hepatosplenomegaly. None had superficial lymphadenopathy. Hematologically, they showed pictures resembling immune related thrombocytopenia and/or hemolytic anemia. Examination of the bone marrows revealed hypercellularity with increased number of megakaryocytes and erythroid cells and various degrees of abnormal lymphoid cell infiltration. The histopathologic section of the spleen from one patient who underwent splenectomy revealed abnormal cell infiltration in the sinusoids of the red pulp. Lymphoma cells showed T gamma/delta lymphoid immunophenotype (CD3+ CD2+ CD4- CD8-, TCR delta-1+, and beta F1-). The platelet counts were elevated transiently after initial treatment with corticosteroids, but the condition soon deteriorated. All died of refractory lymphoma five to nine months after diagnosis. Review of the literature, showed that only four other cases have been reported until now and although no cytogenetic data were available for these patients, they had very similar clinical pictures as those in this series. It is suggested that hepatosplenic T gamma/delta lymphoma represents a rare, but distinct, clinicopathological and cytogenetic entity.

Leptomeningeal seeding with acute hydrocephalus--unusual central nervous system presentation during chemotherapy in Ki-1-positive anaplastic large-cell lymphoma

An unusual central nervous system (CNS) manifestation in a 18-year-old male with Ki-1- positive anaplastic large-cell lymphoma is presented. The diagnosis of Ki-1 lymphoma was first confirmed by the distinct pleomorphic morphology, expression of Ki-1 (CD30) antigen on neoplastic cells and the specific chromosome translocation, t(2;5)(p23;q35). Although young age is thought to be a good prognostic factor in this disease, the course in our patient was very aggressive. At presentation, there was already extensive extranodal involvement, with malignant cell found in the pleural cavity and bone marrow. In spite of rapid shrinkage of whole-body lymph nodes and a decrease in malignant pleural effusion soon after starting chemotherapy, headaches and vomiting ensued in the following days. A computerized tomography scan of the brain showed poor corticomedullary differentiation without definite mass lesions, and numerous malignant cells were found in the cerebrospinal fluid (CSF). Although intrathecal methotrexate was given, the patient died following the sudden onset of acute hydrocephalus. CNS involvement in Ki-1 anaplastic large-cell lymphoma is very rare and most cases present as focal mass lesions in the brain parenchyma. Leptomeningeal seeding of the lymphoma cells with acute hydrocephalus contributing directly to death has never been reported. The experience from this case suggests that CNS involvement may present in variable forms in Ki-1 lymphoma and may be an important cause of mortality in young patients, especially those in advanced stages of the disease. Early detection of CNS involvement by CSF investigation or even prophylactic CNS therapy may be mandatory in these patients.

Genetic diagnosis of haemophilia A of Chinese origin

Genetic diagnosis of haemophilia A has been studied in two aspects. One is to directly identify the mutations in the factor VIII genes of the affected probands, and the other is to examine the usefulness of several intragenic factor VIII markers for gene tracking. Direct mutational analysis by PCR-SSCP (polymerase chain reaction--single-strand conformation polymorphism) has been accomplished previously in 87 haemophilia A patients, accounting for nearly 10% of cases in Taiwan. Of the 87 cases, 46% were with point mutations, short deletions or insertions, and most of the remaining were with gene inversion readily identified by Southern blotting. Further examination of 112 patients has estimated a 33% incidence for gene inversion in all the patients with haemophilia A, or 37% in severe cases. Since the direct mutational detection described above cannot be used in all Chinese families with haemophilia A, genetic markers were also investigated. The two CA repeat markers located at intron 13 (CA-13) and intron 22 (CA-22), respectively, were amplified and analysed simultaneously. Seven different alleles with 18-24 CAs have been identified for CA-13. Alleles of 20 and 21 CAs are the most common and their population frequency was 0.68 and 0.24, respectively. The CA-22 marker contained a repetition of (GT)n(AG)n as was identified in the white European but not in the Canadian population. Alleles with 25 and 26 GT/AGs account for 18% and 75% of this group of samples, respectively. The expected rate of heterozygosity for either CA markers was 68%, although a value of 57% was observed by haplotype analysis, indicating an association of the two repeat markers. Nevertheless, the study of 62 females showed that with the combined use of CA-13 and CA-22 with BclI, approximately 71% would be informative for these markers. This number may increase to 81% if XbaI polymorphism is added. We propose that a better genetic diagnosis procedure for Chinese individuals would be first to look for the inversion mutation, secondly for one of the intragenic markers, and then at the PCR-SSCP analysis.

Correlation of cytogenetic results with immunophenotype, genotype, clinical features, and ras mutation in acute myeloid leukemia. A study of 235 Chinese patients in Taiwan

Of 235 consecutive patients with de novo acute myeloid leukemia (AML), clonal chromosomal abnormalities were detected in 151 (64%) of them. Twenty-four of the 71 patients with M2 AML had t(8;21), 35 of the 36 M3 patients had t(15;17), and 11 of the 45 M4 leukemia disclosed inv(16). Six of the eight patients with 11q23 abnormality had M4 or M5 subtype of leukemia. The incidence of t(15;17) and t(8;21) was higher in our patients than in patients from most Western countries. Immunophenotyping was performed on 197 patients. Patients with t(15;17) were associated with negativity to HLA-DR, CD11b, and CD34. Patients with t(8;21) expressed CD13 and CD33 less frequently than other patients, but all showed CD15 positivity. Coexpression of lymphoid-associated antigens on the leukemic blasts was detected in 52 patients (26%), including all 7 patients with t(9;22), 3 of the 8 patients with t/del(11)(q23), 2 of the 25 patients with t(15;17), and 2 of the 22 patients with t(8;21). Seven (35%) of the 20 patients coexpressing lymphoid markers showed immunoglobulin heavy chain or T-cell receptor beta-chain gene rearrangements, while only 2 (4%) of the 53 patients without lymphoid antigen expression did so. Patients with inv(16), t(8;21), and t(15;17) had a better prognosis than other patients. Of all surface antigens tested, only CD15, CD11b, and HLA-DR were of prognostic value: CD15 with a higher complete remission (CR) rate and CD11b or HLA-DR with a shorter CR duration. N-ras mutations were detected in 7 (18%) of the 40 patients in the study, including two of the three patients with inv(16). This study demonstrated differences in clinical features, immunophenotypes, and genotypes among different cytogenetic subgroups.

Factor VIII gene inversions in severe hemophilia A: results of an international consortium study

Twenty-two molecular diagnostic laboratories from 14 countries participated in a consortium study to estimate the impact of Factor VIII gene inversions in severe hemophilia A. A total of 2,093 patients with severe hemophilia A were studied; of those, 740 (35%) had a type 1 (distal) factor VIII inversion, and 140 (7%) showed a type 2 (proximal) inversion. In 25 cases, the molecular analysis showed additional abnormal or polymorphic patterns. Ninety-eight percent of 532 mothers of patients with inversions were carriers of the abnormal factor VIII gene; when only mothers of nonfamilial cases were studied, 9 de novo inversions in maternal germ cells were observed among 225 cases (approximately 1 de novo maternal origin of the inversion in 25 mothers of sporadic cases). When the maternal grandparental origin was examined, the inversions occurred de novo in male germ cells in 69 cases and female germ cells in 1 case. The presence of factor VIII inversions is not a major predisposing factor for the development of factor VIII inhibitors; however, slightly more patients with severe hemophilia A and factor VIII inversions develop inhibitors (130 of 642 [20%]) than patients with severe hemophilia A without inversions (131 of 821 [16%]).

Acute leukemic transformation of myelodysplastic syndrome--immunophenotypic, genotypic, and cytogenetic studies

The clinical and biological characteristics of myelodysplastic syndrome (MDS) in acute leukemic transformation were studied in 23 patients. All had myeloid transformation according to FAB criteria, but coexpression of lymphoid-associated antigens was detected in five of the 20 patients who underwent an immunophenotypic study. Rearrangement of the immunoglobulin heavy chain gene was also observed in one of the five patients who coexpressed lymphoid markers and that of the T-cell receptor beta chain gene in another one. None had pure lymphoid transformation. Clonal chromosomal abnormalities were noted in 12 (63%) of the 19 patients who underwent cytogenetic study, most commonly - 7 (six patients or 32%). In the 18 patients who underwent serial analyses both at MDS diagnosis and at acute transformation, seven (39%) underwent karyotypic evolution. The most common new or additional aberrations were +8 and +21. N-ras gene mutation was detected in two of the nine patients at acute leukemic transformation. The median interval from diagnosis of MDS to onset of acute transformation was 10 months (1-36 months). Patients with a normal karyotype at diagnosis had a significantly longer chronic phase duration than those with chromosomal abnormalities (median of 20 months vs. 5 months). However, all had a short survival time after diagnosis of acute leukemia, whether chromosomal anomalies were present or not.

Consistent presence of isochromosome 7q in hepatosplenic T gamma/delta lymphoma: a new cytogenetic-clinicopathologic entity

Peripheral T-cell lymphoma (PTL), which is characterized by hepatosplenic presentation and the gamma/delta T-cell receptor (TCR) phenotype on the malignant cells, is a rare but distinct subtype of non-Hodgkin's lymphomas. Little is known about the chromosomal changes in these lymphomas. We report the cytogenetic analysis of three patients who had neoplastic proliferation of T gamma/delta cells in the spleen, bone marrow, and liver, but not in lymph nodes or skin. Isochromosome 7q and trisomy 8 were observed in all three patients. Isochromosome 7q as the sole abnormality has been previously reported in one patient with similar clinicopathologic features. It is suggested that i(7q) is a primary, nonrandom chromosomal abnormality in hepatosplenic T gamma/delta PTL.

Analysis of human platelet glycoprotein IIb-IIIa by fluorescein isothiocyanate-conjugated disintegrins with flow cytometry

Disintegrins are a group of snake venom peptides which inhibit human platelet aggregation by acting as glycoprotein IIb-IIIa (GPIIb-IIIa) antagonists. They are cysteine-rich, Arg-Gly-Asp (RGD)-containing peptides, and bind to GPIIb-IIIa complex on platelet membrane with a very high affinity (Kd, 10(-7)-10(-8) M). In this study, we analyzed GPIIb-IIIa complex on platelet membrane by flow cytometry using fluorescein isothiocyanate (FITC)-conjugated disintegrins as probes. Of these FITC-conjugated disintegrins, FITC-Rhodostomin is the most sensitive probe because Rhodostomin was conjugated with more FITC molecules than Trigramin and Halysin were. The binding fluorescence intensity of FITC-Trigramin (FITC-Tg), FITC-Halysin (FITC-Hy) and FITC-Rhodostomin (FITC-Rn) was measured in both resting and ADP-activated platelets of diluted human platelet-rich plasma. The binding fluorescence of FITC-disintegrins was abolished by EDTA and 7E3, a monoclonal antibody against GPIIb-IIIa. ADP markedly increased the fluorescence intensity of FITC-Tg and FITC-Hy bound on platelets especially when lower doses of these probes were used, whereas it had little effect on that of FITC-Rn. Therefore, FITC-Tg and FITC-Hy can be used for the detection of the activated platelets as noted by a higher ratio of fluorescence intensity (approx. 2-4) between ADP-activated and resting platelets as compared with that (approx. 1-1.3) in the case of FITC-Rn as the probe. The platelets from three patients with Glanzmann's thrombasthenia were probed with FITC-disintegrins.(ABSTRACT TRUNCATED AT 250 WORDS)

Liver function in patients with vitamin K deficiency in infancy

Liver chemistry was studied in fifteen patients with vitamin K deficiency in infancy (VKDI). All except 2 were exclusively breast fed and 4 of the 15 infants had received intramuscular vitamin K prophylaxis. A high incidence of hepatic dysfunction was found during long term follow-up in patients with VKDI. Abnormal aminotransferase was noted either at the time of onset (n = 6) or during the ensuing few weeks (n = 6). Cholestasis was documented in six cases at onset and another two in a later period. Most cases had increased serum alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), or bile acid levels regardless of hepatic enzymes and bilirubin levels. The abnormal enzymes returned to normal after 5 weeks to 23 months. This study demonstrates a close relationship between hepatic dysfunction and VKDI. Liver function impairment other than cholestasis may play some role in the pathogenesis of VKDI, but the cause of hepatic dysfunction can not be defined. Follow-up of liver chemistry is recommended in patients with VKDI. Parenteral vitamin K prophylaxis at birth may not give sustained protection against VKDI, especially in those with underlying liver disease.

Characterization of a factor IX variant with a glycine207 to glutamic acid mutation

Factor IXTaipei9 is a factor IX variant from a hemophilia B patient with reduced levels of circulating protein molecules (cross-reacting material reduced, CRM). This variant contained a glycine (Gly) to glutamic acid (Glu) substitution at the 207th codon of mature factor IX. The functional consequences of the Gly-->Glu mutation in factor IXTaipei9 (IXG207E) were characterized in this study. Plasma-derived IXG207E exhibited a mobility similar to that of normal factor IX on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Its specific activity was estimated to be 3.5% that of the purified normal factor IX in a one-stage partial thromboplastin time assay (aPTT). Cleavage of factor IXG207E by factor XIa or factor VIIa-tissue factor complex appeared to be normal. When the calcium-dependent conformational change was examined by monitoring quenching of intrinsic fluorescence, both normal factor IX and IXG207E exhibited equivalent intrinsic fluorescence quenching. Activated factor IXG207E (IXaG207E) also binds antithrombin III equally as well as normal factor IXa. However, aberrant binding of the active site probe p-aminobenzamidine was observed for factor XIa-activated factor IXG207E, indicating that the active site pocket of the heavy chain of factor IXaG207E was abnormal. Moreover, the rate of activation of factor X by factor IXaG207E, as measured in a purified system using chromogenic substrates, was estimated to be 1/40 of that of normal factor IXa. A computer-modeled heavy-chain structure of factor IXa predicts a hydrophobic environment surrounding Gly-207 and this Gly forms a hydrogen bound to the active site serine-365. The molecular mechanism of the Gly-->Glu mutation in factor IXTaipei9 might result in the alteration of the microenvironment of the active site pocket which renders the active site serine-365 inaccessible to its substrate.

Use of retinoic acids in the treatment of peripheral T-cell lymphoma: a pilot study

PURPOSE

We have systemically analyzed, both in vitro and in vivo, the effect of 13-cis-retinoic acids (RA) on non-Hodgkin's lymphoma (NHL).

METHODS

The in vitro growth-inhibitory effect of 13-cis-RA was examined in 11 (T cell, five; B cell, six) lymphoma cell lines by a tetrazolium colorimetric assay. A pilot clinical trial with oral 13-cis-RA 1 mg/kg/d was conducted in a selected group of 18 lymphoma patients, of whom 16 had failed to respond to at least one regimen of intensive chemotherapy. The in vitro and in vivo effects of 13-cis-RA were correlated with immunophenotypes, RA-induced changes of morphology, and patterns of DNA fragmentation of the lymphoma cells.

RESULTS

Four of five T-lymphoma cell lines and none of six B-lymphoma cell lines were sensitive (concentration of 50% growth inhibition [IC50] < 1.5 microns) to 13-cis-RA (P = .015). In the clinical trial, five (two Ki-1, one angioinvasive type, one diffuse mixed cell, and one diffuse large cell) complete remissions and one (Ki1) partial remission were observed in 12 patients with peripheral T-cell lymphoma (PTCL), while none of six patients with B-cell lymphoma responded to 13-cis-RA. 13-cis-RA-induced cellular differentiation and apoptosis, as evidenced by the more mature morphology, characteristic nuclear condensation, and DNA ladder pattern signifying internucleosomal fragmentation, were demonstrated in the sensitive cell lines, as well as in the remitting lymphoma tissues.

CONCLUSION

The 13-cis-RA appears to be active on lymphomas of T-lineage and their therapeutic indication may be extended to include some subtypes of PTCL. The mechanisms of action are related to differentiation and apoptosis of lymphoma cells. There appears to be no cross-resistance between 13-cis-RA and conventional chemotherapy.

Cytogenetic studies, ras mutation, and clinical characteristics in primary myelodysplastic syndrome. A study on 68 Chinese patients in Taiwan

Cytogenetics and clinical features were studied for 68 Chinese patients with primary myelodysplastic syndrome (MDS). Ras mutation was analyzed in 25 of them. Thirty-four patients (50%) had clonal chromosomal abnormalities at initial analysis. The most common cytogenetic aberrations were -7, +8, 5q-, and 20q-, which occurred in 11 (16.2%), seven (10.3%), five (7.4%) and three patients, respectively. The incidence of -7 was higher and that of 5q- lower in our patients than in patients from most other geographic areas. The 17 patients with multiple chromosomal abnormalities had a significantly shorter median survival (9 months) than the 34 patients with normal karyotype (33 months) and the 17 patients with patients with single anomalies (26 months). Evolution to acute leukemia occurred in 20 patients (29%) after a median interval of 8 months following the diagnosis. Patients with multiple cytogenetic changes at initial analysis or in subsequent studies had a significantly higher frequency of acute transformation than others (55% vs. 18.6%, p = 0.007); the same was not true if only the data of initial study were considered. Serial cytogenetic studies are important in patient follow-up. N-ras mutation was detected in 5 (20%) of 25 patients within the study. There was no correlation between the gene mutation and acute transformation. But combing the data of N-ras mutation and cytogenetics, patients with either the N-ras mutation or clonal chromosomal abnormalities were at significantly higher risk for developing acute leukemia than those with neither of the changes (77% vs. 25%).

Hematophagic histiocytosis: a clinicopathologic analysis of 23 cases with special reference to the association with peripheral T-cell lymphoma

The clinicopathologic features of 23 patients with hematophagic histiocytosis (HH) are described. All of them exhibited increased histiocytes associated with hemophagocytosis in the marrow. The patients usually presented with fever, hepatosplenomegaly, lymphadenopathy, and cytopenia. The underlying illnesses were heterogeneous, including non-Hodgkin's lymphoma in 17, systemic lupus erythematosus in one, diabetes mellitus in one, acute myelomonocytic leukemia in one, myelodysplastic syndrome in one, and unknown cause in two. Among 17 non-Hodgkin's lymphoma, 14 were peripheral T-cell lymphoma, two were B-cell lymphoma, and one was an undefined phenotype. Among 14 patients with peripheral T-cell lymphoma, six of the patients had nasal T-cell lymphoma. Five of these 14 patients initially diagnosed as malignant histiocytosis turned out to be T-lineage lymphoma after immunophenotypic studies. Active infections, most of viral origin, were documented in eight patients, including Epstein-Barr virus in three, cytomegalovirus in three, herpes simplex virus in three, Pseudomonas aeruginosa in one, Bacteroides vulgatus in one, and mycoplasma in one. Some of them had mixed virus and bacteria infection. Sixteen (70%) of our patients died of their acute illness within 10 weeks of the diagnosis of HH. In the past, the clinical and histologic differentiation between hematophagic histiocytosis and true histiocytic neoplasm (histiocytic medullary reticulosis/malignant histiocytosis) has proved difficult, but now these can be distinguished with immunohistologic, immunogenetic, and cytogenetic studies, especially in the cases of peripheral T-cell lymphoma with hemophagocytic syndrome.