Search PubMed⌕ Search

Biomedical subjects

J M Flexner

Publications and source records attributed to J M Flexner.

68 records · Page 4Linked to original sources

Transformation of mouse cells by fusion with chronic granulocytic leukemia cells: possible role of human chromosome.

In vitro properties of somatic cell hybrids between non-malignant B82 mouse fibroblasts and human chronic granulocytic leukemia spleen cells include lack of cell density-dependent growth inhibition and growth in soft agar. These phenotypic expressions of cell transformation appear linked to the retention by the cells of chromosome 7 from the human leukemic genome.

Animals↗

Malignant lymphomas of follicular center cell origin in man. I. Immunologic studies.

Lymphomas with histologic features indicating a follicular center cell (FCC) origin were analyzed from 26 patients of a group of 45 consecutive non-Hodgkin's lymphoma patinets whose tumors were studied for B- and T-cell characteristics. They were compared with benign, reactive lymphoid tissue from 14 patients. Cell suspensions from biopsy material, blood, or bone marrow were examined for surface Ig and for rosette formation with sheep erythrocytes (E rosettes). Of the 26 patients with FCC lymphomas, 22 had 40% or more Ig-bearing cells; all patients with FCC lymphoma tissues had 25% or less E rosette-forming cells. Cells from most FCC lymphomas of the cleaved type had surfac IgM; those from several FCC lymphomas had both IgM and IgD. Cells from lymphomas of noncleaved cell type had surface IgG or IgA. Light-chain analysis showed that cells from FCC lymphomas bore a predominant light-chain type, which indicated their monoclonal nature. Neoplastic cells from several FCC lymphomas synthesized the surface Ig which they bore. Reactive tissues usually contained fewer Ig-bearing and more E rosette-forming cells than FCC lymphomas; the Ig-bearing cells, with one exception, had a polyclonal distribution. Correlation of histologic and immunologic observations indicates that most lymphomas identified as FCC in origin by light micorscopic criteria mark as B cells with the use of immunologic techniques and that FCC lymphomas are the most common type of non-Hodgkin's lymphoma.

B-Lymphocytes↗

Malignant lymphomas of follicular center cell origin in man. II. Ultrastructural and cytochemical studies.

Tissues from malignant lymphomas with both nodular and diffuse growth patterns, thought by light microscopy to be composed of cells of follicular center cell (FCC) origin, Were examined by electron microscopy; the tumor cells were similar to lymphoid cells found in reactive follicular centers. Tumor cells from neoplasms thought to be composed of cleaved FCC often had more pronounced nuclear folding than did cleaved FCC of reactive follicles, whereas cells in tumors of noncleaved FCC type were indistinguishable from their presumed counterparts in reactive follicles. Large cell noeplasms, previously classified as "histiocytic" lymphomas were composed of cells with ultrastructural characteristics of transformed lymphocytes; they showed neither ultrastructural nor cytochemical features of mononuclear phagocytes. These findings support the concept that a major group of lymphomas arises from lymphocytes of follicular centers.

B-Lymphocytes↗

Chromosome band analysis in 19 cases of chronic myeloid leukemia: 9 chronic, 10 blastic, two with Ph1 (22q-) translocation on 17 short arm.

The results of Giemsa band analyses of the marrow cells of 19 cases of CML in the chronic or blast phase are reported. All but one of the 14 Ph1 positive cases showed the 9q+pattern, the exceptional one being 16p+. All 10 blast cases showed additional rearrangements, which are described. In two of the cases, one blastic, one chronic, which were -22, Ph1 negative, the 22q- member was identified as a translocation on the short arm of one 17 which was dicentric.

Chromosome Aberrations↗

17 long arm isochromosome. A common anomaly in malignat blood disorders.

A cytogenetic anomaly consisting in the replacement of a 17 by its long arm isochromosome was identified as the only alteration in the marrow cells of two patients with acute granulocytic leukemia. In one case, the specific nature of the abnormal chromosome was established by newly available techniques. Since its identification in 1965, this structural anomaly, which implies 17 long arm duplication and short arm deletion, has been observed, as a sole or as an associated finding, in the malignant cells of a spectrum of blood disorders, including acute granulocytic leukemias, the blast crisis of chronic myeloid leukemia and lymphoreticular proliferative disorders. Attention is called to this particular rearrangement for its clinical as well as fundamental implications, as its presence in blood forming cells unfailingly hearalds a fast, fatal course of evolution.

Aged↗

Malignant lymphomas of follicular centre cell origin in man. VII. Prognostic features in small cleaved cell lymphoma.

To extend the clinical-pathologic description of small cleaved cell lymphoma (SCCL), we reviewed the records of 106 patients with SCCL who were treated in accordance with a policy of watchful waiting and palliative therapy. Median age was 58 years. A pure diffuse pattern was seen in only 16 per cent of cases. Stage III or IV disease was present in 85 per cent of patients; marrow involvement was noted in 60 per cent of patients. 'B' symptoms were present in 25 per cent of patients. By univariate analysis, age greater than 60, diffuse pattern, stage IV disease, involvement of liver, lung, pleura, or g-i tract, 'B' symptoms, surface heavy chain IgM or IgM-D, and LDH greater than 200 IU/dl were found to be significantly associated with a poor prognosis. Marrow involvement, increased (5-25 per cent) transformed (non-cleaved) cells, and surface light chain had no prognostic significance. By multivariate analysis, only age greater than 60, stage IV disease, and LDH greater than 200 IU/dl were prognostically significant. For patients with all three unfavourable prognostic features, median survival was only 11 months. For patients with age less than or equal to 60, stage I, II, or III disease, and LDH less than or equal to 200 IU/dl, median survival was not reached at 180 months. Recognition of prognostic features in indolent lymphoma can help clarify whether the results of treatment protocols represent true advances or the mere selection of favourable patients.

Aged↗

Clinical features associated with transformation of cerebriform T-cell lymphoma to a large cell process.

Some patients with cerebriform T-cell lymphoma (CTCL) undergo morphologic transformation to a large cell lymphoma. From a series of 113 patients with CTCL, 22 patients were identified with transformed CTCL. Stages of involvement at diagnosis were: I (seven), II (four), III (four), IV (seven). Nine patients had transformation at the initial diagnosis while the median time from diagnosis to transformation in the other 13 patients was 16 months (range: 3 months-6 years). Thirteen had transformation extracutaneously: lymph nodes (eight), central nervous system (two), and other extranodal sites (three). T cell markers were identified in all cases; of 15 cases with complete phenotypes, there were eight T-helper, three T-suppressor, and four aberrant T phenotypes. Serology for human T-leukemia virus-I (HTLV-I) was negative in eight patients tested. Median survival from diagnosis was 27 months compared to 53 months in 53 patients without transformation (p = 0.003). Despite combination chemotherapy in 12 patients following transformation, median survival after transformation was 12 months and only 7 months with extracutaneous disease. The likelihood of transformation could not be predicted by the initial histology, immunophenotype, or stage of disease.

Adolescent↗

Age and cytogenetics as predictors of event free survival in patients with acute non-lymphocytic leukemia receiving high dose cytosine arabinoside and daunorubicin as consolidation chemotherapy.

Between 1991 and 1999, 67 patients with acute non-lymphocytic leukemia (ANLL) in complete remission received high dose cytarabine (HiDAC) 3 gm/m2 q12h x 12 doses followed by daunorubicin 45 mg/m2/day x 3 days as consolidation therapy. Five year actuarial event free survival (EFS) was 34% +/- 6%. Age was significantly associated with EFS. EFS was 60% +/- 15% in patients age 20 to 29, 48% +/- 16% in patients age 30 to 39, 23% +/- 10% in patients age 40 to 49, 31% +/- 11% in patients age 50 to 59, and 0% in patients age > or = 60. Contrary to other reports which have used different HiDAC regimens, we found no relationship between cytogenetics and EFS. Cytogenetics were defined as favorable risk: t(8;21), inv (16), and del (16); neutral risk: normal or t(15;17); and unfavorable risk: any abnormality not included in favorable risk or neutral risk. EFS was 29% +/- 17% in patients with favorable cytogenetics, 37% +/- 14% in patients with neutral cytogenetics, and 31% +/- 12% in patients with unfavorable cytogenetics. These differences were not statistically significant. Because of the successful use of allogeneic transplantation at relapse in patients with matched related donors, five year actuarial survival (S) in this series was 40% +/- 6%. Five year actuarial survival was 57% +/- 9% for patients age < or = 44 and 25% +/- 8% for patients age > or = 45. This difference is statistically significant, p < .025. Clinicians should be cautious about making clinical decisions regarding consolidation therapy of ANLL on the basis of the presence or absence of cytogenetic abnormalities as the importance of cytogenetics may depend on the specific therapy which is employed.

Actuarial Analysis↗