Search PubMed⌕ Search

Biomedical subjects

H F Tien

Publications and source records attributed to H F Tien.

At least 55 records · Page 3Linked to original sources

Cytogenetic characterization of Epstein-Barr virus-associated T-cell malignancies.

Recently, Epstein-Barr virus (EBV) infection has been found not only to be associated with Burkitt lymphoma and nasopharyngeal carcinoma but also with some T-cell malignancies. Cytogenetic studies were performed on four Chinese patients with EBV-associated T-cell neoplasms: three peripheral T-cell lymphomas and one large granular lymphocyte leukemia with coexpression of T-cell antigen. Clonal chromosomal abnormalities were detected in all four patients. Rearrangements of chromosome 7 were observed in three patients: one at 7p22, one at 7q35 or 36, and the remaining one at both sites. The last patient also had a chromosomal abnormality involving 14q11. Trisomy of part of the 1q segment was detected in two patients. The results revealed that the chromosomal abnormalities in these patients were similar to those observed in other T-cell lymphomas. Further studies on more patients are necessary to find out whether there are specific chromosomal aberrations in EBV-associated T-cell neoplasms.

Adolescent↗

Comparison of clinical and biologic features between myeloid and lymphoid transformation of Philadelphia chromosome positive chronic myeloid leukemia.

Analysis of clinical and biologic features of chronic myeloid leukemia (CML) in blast crisis (BC) was performed on 36 patients: 25 had myeloid and 11 had lymphoid transformation. The median duration from diagnosis to onset of BC was significantly shorter in patients with lymphoid BC (6 months) than in those with myeloid BC (41 months). Patients in lymphoid transformation showed better response to therapy and had a significantly longer median survival time after BC than patients with myeloid transformation (56% vs 0% and 10 months vs 4 months, respectively). The leukemic cells from all the patients with lymphoid BC showed B-cell immunophenotype, confirmed by the presence of immunoglobulin (Ig) heavy chain gene rearrangements in the five patients studied. Two of the eight patients with complete marker study expressed myeloid-associated antigens on the blasts. A high incidence of CD7 expression (7/17 or 41%) was found in patients with myeloid BC, but none of the patients who had DNA analysis showed rearrangement of T-cell receptor beta chain gene. Chromosomal abnormalities +8, +19, +21, and i(17q) were detected only in the patients with myeloid BC but not in those with lymphoid BC. Combined analysis of the patients in this series and those reported previously has revealed a statistically significant difference in the distribution of bcr breakpoints between myeloid and lymphoid BC: the bcr breakpoints in more than half of the patients with myeloid crisis were mapped to Zone 2 while those in patients with lymphoid crisis occurred most frequently in Zone 3.

Adolescent↗

Characterization of acute myeloid leukemia (AML) coexpressing lymphoid markers: different biologic features between T-cell antigen positive and B-cell antigen positive AML.

The clinical and biologic characteristics of acute myeloid leukemia (AML) with coexpression of lymphoid-associated antigens (Lym+ AML) were studied from 39 cases who represented 24% of 161 newly diagnosed de novo AML. Twenty-seven cases (16.8%) were positive for the expression of T-cell markers (T+ AML) and 12 (7.5%) for B-cell markers (B+ AML). Chromosomal abnormalities t(9;22)(q34;q11) and t/del(11)(q23), which were considered to be associated with acute leukemia coexpressing markers of more than one cell lineage, were detected in five and in four patients, respectively. There was no prognostic significance of B-cell or T-cell antigen expression in AML. Of 12 T+ AML cases in which cells were available for gene analysis, all showed germline configuration of immunoglobulin heavy chain and T-cell receptor beta chain genes, while seven of nine B+ AML showed rearrangements of either or both of the genes. Double labeling of the cells with myeloperoxidase and lymphoid markers demonstrated that individual blasts in all the five T+ AML tested were simultaneously expressing myeloperoxidase activity and CD7; however, most blasts in the three B+ AML studied expressed either myeloperoxidase activity or CD10, but not both. In eight of the nine T+ AML tested, the T-cell antigen-positive leukemic blasts were significantly decreased to less than 10%, after in vitro culture with the differentiation-inducing agent phorbol ester. B-cell markers remained positive (> or = 20%) on the cells in the two B+ AML who had the same study. These findings suggested that T+ AML and B+ AML might have different biologic features. Further studies on more patients are needed to clarify this point.

Acute Disease↗

Cytogenetic study of acute lymphoblastic leukemia and its correlation with immunophenotype and genotype.

Among 72 Chinese patients with acute lymphoblastic leukemia (ALL), 50 had clonal chromosomal abnormalities. Structural abnormalities were detected in 42 patients: these included t(9;22) in 9, t(1;19) in 6, t(4;11) in 5, del(11)(q23) in 4, and del(6q) in 4. Adults had a higher incidence of t(9;22) and t(1;19) but a lower incidence of t(4;11) and hyperdiploid greater than 50 karyotype than children. A significant difference was also noted in white blood cell (WBC) count among various karyotypic groups. Patients with chromosomal abnormalities t(9;22), t(1;19), t(4;11) and del(11) (q23) had a shorter complete remission duration as compared with patients free of these abnormalities. Immunophenotyping was performed on 69 patients. All patients with t(9;22), t(1;19), and t(4;11) had B-lineage ALL restricted to certain stages of maturation: groups III and IV, groups IV and V, and group II, respectively (according to the classification of Foon and Tood). Among patients with t(9;22), t(4;11), and del(11)(q23), which have been considered to be associated with acute mixed-lineage leukemia, one each, respectively, showed myeloid antigen expression on the leukemic blasts (My+ ALL). No cross-lineage rearrangements of immunoglobulin (Ig) or T-cell receptor (TCR) genes were detected in these karyotypic subgroups of patients who underwent gene analysis.

Adolescent↗

Cutaneous angiocentric T-cell lymphoma associated with Epstein-Barr virus.

BACKGROUND: Two unusual cases of cutaneous angiocentric T-cell lymphoma were found to be associated with Epstein-Barr virus infection. OBJECTIVE: The objective was to study the clinical course and the response of the disease to conventional chemotherapy. METHODS: Histologic specimens from both patients were studied. Clonal proliferation was assessed by Southern blot hybridization. RESULTS: The disease in both patients was rapidly progressive and responded poorly to aggressive treatment. Biopsy specimens showed infiltration of atypical lymphoid cells with angiocentricity and angiodestruction, which probably resulted in the observed tissue necrosis. Clonal proliferation of Epstein-Barr virus DNA was detected in tissue from primary skin lesions and disseminated nasal lesions. CONCLUSION: Epstein-Barr virus-associated angiocentric T-cell lymphoma in our patients was characterized by an aggressive course and resistance to conventional chemotherapy. A search for Epstein-Barr virus and the human T-lymphotropic virus should be performed in patients with atypical features of cutaneous T-cell lymphoma.

Adult↗

Inactivation of the retinoblastoma gene in acute myelogenous leukaemia.

To investigate the role of retinoblastoma susceptibility (RB) gene inactivation in leukaemogenesis, we evaluated 36 bone marrow specimens of acute leukaemia for RB protein expression by immunoprecipitation and Western blot analysis. 15 patients had no detectable RB protein at initial screening. However, nine of them were subsequently excluded due to evidence of protein degradation. Of 27 valid cases, six (22%) were repeatedly shown to lack expression of the RB protein with three different anti-RB antibodies. Five were patients with acute myelogenous leukaemia (AML) and one, mixed-lineage acute leukaemia. The RB inactivation was noted more frequently in AML (5/18, 28%) than in acute lymphoid leukaemia (0/7, 0%). By karyotyping, none of these six patients exhibited cytogenetic changes involving chromosome 13q14, the RB locus. There is no correlation between inactivation of the RB gene and FAB subtypes or cytogenetic changes. Four patients achieved complete remission with standard chemotherapy for 6, 12, 20 and 26+ months, respectively. Southern and Northern blot analyses further indicated that the RB genes were grossly intact and the level of RB transcripts did not decrease in the majority of these six patients. These results suggest that the absence of RB products in some of acute leukaemia might be regulated at the post-transcriptional level, and it imposes no significant effect on treatment response and prognosis.

Adolescent↗

Characterization of Philadelphia-chromosome-positive acute leukemia by clinical, immunocytochemical, and gene analysis.

Philadelphia chromosome (Ph') was detected at presentation in 10 out of 110 patients with acute lymphoblastic leukemia (ALL) and five of 168 patients with acute myelogenous leukemia (AML). Two other ALL patients who had studies at relapse were also included in the analyses. One of the 12 Ph'-positive (Ph+) ALL patients had simultaneous expression of myeloid-associated antigen on the leukemic blasts, while all the five AML patients coexpressed markers of lymphoid cells. Double labeling of the cells with myeloperoxidase and CD10 on three Ph+ AML cases showed that most leukemic blasts expressed either myeloperoxidase activity or CD10 but not both. Cross-lineage gene rearrangements of T-cell receptor (TCR) beta-chain gene were detected in three of the eight Ph+ ALL patients tested. All the four Ph+ AML cases studied showed immunoglobulin heavy chain gene rearrangements, and three of them also had simultaneous rearrangements of TCR beta-chain gene. The results revealed that Ph+ acute leukemia in this study belonged either to ALL or mixed lineage leukemia, and none was pure AML. This finding is contrary to that of acute blast crisis of chronic myelogenous leukemia in which the majority of patients had myeloid transformation. Rearrangements of bcr were detected in four of the 10 Ph+ ALL and three of the four Ph+ AML patients tested. No significant difference was noted in the clinical or hematologic manifestations among Ph+ leukemia with or without bcr rearrangements.

Adult↗

Immunoglobulin and T-cell receptor gene rearrangements in acute lymphoblastic leukemia--a higher incidence of double rearrangements in patients with myeloid antigen expression.

Among 160 patients who were diagnosed as having acute lymphoblastic leukemia (ALL) by French American British (FAB) criteria, 32 patients (20%) expressed myeloid-associated antigens on leukemic blasts (My+ALL). Correlation of immunophenotype with rearrangement of immunoglobulin (Ig) heavy chain and T-cell receptor (TCR) beta chain genes was performed on 73 of these patients (21 were My+ALL). Rearrangements of both Ig and TCR genes (double rearrangements) were detected in 24 patients, including three (19%) of 16 T-lineage ALL. 17 (33%) of 52 B-lineage ALL, and four of five ALL expressing both B and T-cell surface markers. Also a higher incidence of double rearrangements in My+ALL was found as compared with My-ALL (43% vs 29%). This difference was more evident when only B-lineage ALL was considered (50% in My+ patients vs 24% in My- patients). However the difference is not statistically significant yet possibly due to the small number of patients in the study. Further studies on more patients are needed to confirm this. In My-B-lineage ALL, rearrangements of TCR beta chain gene were restricted to certain subgroups (Groups III & IV) of patients who expressed CD10 surface antigens but lacked cytoplasmic Ig. In My+ B-lineage ALL, rearrangements of TCR beta chain gene could be found in various subgroups studied (Groups II through V). Cross-lineage gene rearrangement in My+ALL may involve mechanisms different from those in My-ALL.

Adolescent↗

A subset of acute lymphoblastic leukemia with co-expression of myeloid antigens: prevalence and clinical significance.

In order to evaluate the biological features and clinical significance of myeloid antigen expression in acute lymphoblastic leukemia (ALL), immunophenotype analysis was performed on leukemic cells from 160 patients diagnosed as ALL by the French, American and British (FAB) criteria using a comprehensive panel of monoclonal antibodies to lymphoid and myeloid associated antigens. Expression of myeloid antigens was found in 32 cases (20%), including 11 out of 49 adults (22.4%) and 21 out of 111 children (18.9%). CD33 was positive in 18 patients (11.3% of the total cases), CD13 in 15 patients (9.4%), CD 11b in 12 patients (7.5%) and CD14 in 1 patient (0.6%). Nine patients expressed two or more myeloid antigens. There were no significant differences in clinical manifestations and hematological pictures between the ALL patients with myeloid antigen expression (My+ ALL) and those without (My- ALL). No consistent chromosomal abnormality was found in My+ ALL. Eighty percent of the childhood and 44.4% of the adult My+ ALL patients achieved complete remission, compared with 87% and 80%, respectively, for childhood and adult My- ALL, but the differences were not statistically significant. After a median follow-up of 2.1 years, there were also no statistically significant associations between myeloid antigen expression and shorter duration of remission or poorer survival rate for patients with both adult and childhood ALL.

Adult↗

Epstein-Barr virus-associated peripheral T-cell lymphoma of activated CD8 phenotype.

Two childhood cases are reported of peripheral T-cell lymphoma; the neoplastic cells expressed activated CD8 (T8) phenotype and contained Epstein-Barr viral (EBV) DNA. Both patients had an aggressive and rapid clinical course despite chemotherapy. Elevated titers of antibodies to EBV-viral capsid antigen (greater than 640) and early antigen (greater than 10) were found in both patients. Histology revealed pleomorphic immunoblastic lymphoma with extensive necrosis in one case and an angioimmunoblastic lymphadenopathy-like pattern containing Reed-Sternberg-like giant cells in the other. Southern blot hybridization studies showed clonal rearrangement of the T-cell-receptor beta gene in both cases, and a cytogenetic study on one case revealed clonal structure abnormality involving chromosomes 1, 6, 7, 10, and 19. Analysis of the tumor DNA showed a high copy number of EBV genome per cell compared with that of Raji and Marmoset B 95.8 lines; the study for human T-cell leukemia virus type I was negative. The EBV genome was found by in situ hybridization in the tumor nuclei in both cases. In addition to Burkitt's lymphoma, T-cell lymphoma of the helper phenotype, and Hodgkin's disease, EBV can contribute to the development of CD8-positive aggressive T-cell lymphoma.

Adolescent↗

Deletion of the human retinoblastoma gene in primary leukemias.

As an initial step in evaluating the role of tumor suppressor genes in leukemogenesis, we surveyed primary leukemia cells from 130 patients for possible deletion of the retinoblastoma susceptibility (Rb) gene by Southern blot analysis. Two of them clearly showed homozygous deletion of Rb alleles. The first patient was a pre-B acute lymphoid leukemia (ALL) associated with a cytogenetic translocation: t(14;16)(q24;q22). The deletion was located at the 3' portion of the Rb gene, very close to the site of Rb gene deletion recently identified in an ALL cell line. The absence of Rb110 protein was further confirmed by Western blot analysis. The second patient was a chronic myelomonocytic leukemia (CMMoL), terminated in acute blastic transformation. Deletion of the 5' portion of Rb gene was found in leukemic cells in the chronic stage. The results indicated that inactivation of the Rb gene occurred in certain cases of leukemia. Its significance warrants further study.

Aged↗

Cytogenetic characterization of a nasopharyngeal carcinoma cell line and its subline.

Cytogenetic results of a nasopharyngeal carcinoma (NPC) cell line NPC-TW039 and its subline NPC-TW039-N1, established from the nude mouse transplant, were reported. This is the third case of NPC presented with banded karyotype, to date, in the literature. A 3q + marker chromosome, with involvement of band q25 similar to that present in the two previously reported cases, was detected in most tumor cells from both cell lines. The structural chromosome abnormalities of NPC-TW039-N1 were similar to its original cell line, NPC-TW039, except that the subline lost one marker chromosome and gained a new one.

Chromosome Aberrations↗

bcr rearrangements in Philadelphia chromosome-positive acute lymphoblastic leukemia. A study of five Chinese patients in Taiwan.

Cytogenetic studies were successfully conducted on 73 Chinese patients with acute lymphoblastic leukemia (ALL). A Philadelphia chromosome (Ph) was identified in four (9%) of the 46 children and in four (15%) of the 27 adults. None of these patients had any clinical features suggestive of chronic myelogenous leukemia (CML). Leukemic cells from five of the eight Ph-positive (Ph+) ALL patients were analyzed for bcr rearrangement by Southern blot analysis with three restriction enzymes and two bcr probes. One of the three children and both adult patients studied showed bcr rearrangement. Based on the data from the literature and the present study, 58% of adult and 14% of childhood Ph+ ALL patients demonstrated bcr rearrangement. There were no significant differences in clinical or laboratory findings between the two groups of patients with or without bcr rearrangement. Patients who had Ph+ ALL but no bcr rearrangement appear to have been victims of de novo acute leukemia, but it was still difficult to determine whether patients with bcr rearrangement had acute lymphoid transformation of subclinical CML. More studies and longer follow-ups are needed for clarification.

Adolescent↗

Infant leukemia: an analysis of nine Chinese patients.

A study was made of the cellular and molecular characteristics of nine Chinese infants, consecutively presenting with acute leukemia. Five cases were acute lymphoblastic leukemia (ALL); four were acute nonlymphoblastic leukemia (ANLL). Hyperleukocytosis, hepatosplenomegaly, and poor response to conventional therapy were common features, and CNS involvement was detected at diagnosis in three cases. The blast cells from all five cases with ALL expressed early B-cell markers, i.e., HLA-DR+, CD19+, but CD10-. Terminal deoxynucleotidyl transferase (TdT) was present in blasts from four of the five cases and periodic acid-Schiff staining in blasts from two patients only. The leukemic cells of one patient also showed positive nonspecific esterase activity and expressed myeloid-associated antigens CD33 (My9), CD11 (OkM1), and CD14 (My4 and Mo2). Molecular analysis of leukemic cell DNA from this and two other patients showed rearrangement of the immunoglobulin (Ig) heavy-chain genes, but without any evidence of kappa light-chain gene rearrangement. T-cell receptor (TCR) genes remained in the germline configuration in these cases. Cytogenetic analysis showed translocation t(4;11) (q21;q23) in all four cases studied. In the group of ANLL, three cases belonged to the M4 and one to the M2 subtype. Chromosomal abnormality involving 11q23 was also detected in two patients: t(11;17)(q23;q11) and del(11)(q14q23) in each case respectively. Neither Ig nor TCR gene rearrangement was present in blast cells from patients with ANLL. The data indicate that chromosomal rearrangement of band 11q23 was quite common in Chinese infants with either form of leukemia, a finding that may have pathogenetic implications.

Antigens, CD↗