Ming-Ching Shen

Methylation of the p15INK4B 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 p15INK4B gene methylation in myelodysplastic syndrome (MDS) and its correlation with leukaemic transformation and survival of patients, the methylation status of the p15INK4B promoter region was analysed in 50 patients and was serially studied in 22 of them. Of the 50 patients, 17 (34%) showed p15INK4B 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 p15INK4B 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 p15INK4B methylation showed disease progression to AML; it could be detected before, at the time or after the diagnosis of leukaemic transformation. p15INK4B methylation in MDS patients implicated a shorter survival time in univariate analyses, but its prognostic significance disappeared in multivariate analyses. In conclusion, p15INK4B 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.

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.

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.

SOCS1 methylation in patients with newly diagnosed acute myeloid leukemia.

The proliferation and differentiation of hematopoietic precursor cells depend on various cytokines. The suppressor of cytokine signaling‐1 (SOCS1) down‐regulates Janus kinases/signal transducers and activators of transcription (JAK/STAT) pathway activity and inhibits the biological effects of cytokines. SOCS1 has been shown to have tumor‐suppressor activity, and methylation of this gene, resulting in transcriptional silencing, has been found in 65% of hepatocellular carcinoma and has been suggested to play an important role in the development of the cancer. The methylation status of the SOCS1 gene in acute myeloid leukemia (AML) has not been reported before. In this study, we analyzed SOCS1 methylation in 89 patients with newly diagnosed AML and correlated the result with immunophenotypes, cytogenetics, clinical features, and treatment outcome. SOCS1 methylation was found in the leukemic cells from 53 patients (60%). Thirteen (76%) of the 17 patients with t(15;17) had SOCS1 methylation, whereas this gene was methylated in only one (11%) of the nine patients with t(8;21). The frequencies of SOCS1 methylation among various cytogenetic subgroups differed significantly (P = 0.014). Other clinical and laboratory parameters and the disease‐free survival and overall survival were similar between patients with and without SOCS1 methylation. In conclusion, SOCS1 methylation occurs in more than half of AML cases, correlates with cytogenetic abnormalities, and may play an important role in the development of subsets of AML.

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.

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.

Epidemiology of multiple myeloma in Taiwan: increasing incidence for the past 25 years and higher prevalence of extramedullary myeloma in patients younger than 55 years.

The incidence of multiple myeloma (MM) is lower in Asia than in western countries. However, no data are available on descriptive epidemiology of MM in Chinese.

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.

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-Hodgkins 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.

A subset of acute nonlymphocytic leukemia with expression of surface antigen CD7— morphologic, cytochemical, immunocytochemical and t cell receptor gene analysis on 13 patients

An increasing number of acute leukemias coexpressed markers normally believed to be restricted to a single lineage have been found recently. This special subgroup of leukemias have drawn a lot of attention because of their biologic and clinical significance. In a study of 100 consecutive de novo ANLL patients diagnosed by FAB criteria, T-cell antigen CD7 was identified on the leukemic blasts of 13 patients, ten of whom had M1 subtype of leukemia, myeloblastic leukemia without maturation. All the patients showed positive staining with myeloperoxidase and expressed myeloid markers CD13 and/or CD33, but lacked CD11b, a marker of more mature myeloid cells. Combined staining with myeloperoxidase and CD7 of the cells from four patients revealed coexpression of both markers on the same cells. None of the patients expressed the two other T-cell antigens CD2 or CD5. All ten patients who had DNA analysis showed germline configuration of TCR beta and gamma chain genes. One patient had chromosomal translocation involving 11q23, t(11; 19) (q23; p13), which is the site frequently associated with both myeloid and lymphoid malignancies. The clinical implications of this subgroup of patients need further study on more patients, and need longer follow-up.