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J Cossman

Publications and source records attributed to J Cossman.

At least 19 recordsLinked to original sources
PubMed1999

Reed-Sternberg cell genome expression supports a B-cell lineage.

The malignant Reed-Sternberg cell of Hodgkin's disease, first described a century ago, has resisted in-depth analysis due to its extreme rarity in lymphomatous tissue. To directly study its genome-wide gene expression, approximately 11,000,000 bases (27,518 cDNA sequences) of expressed gene sequence was determined from living single Reed-Sternberg cells, Hodgkin's tissue, and cell lines. This approach increased the number of genes known to be expressed in Hodgkin's disease by 20-fold to 2,666 named genes. The data here indicate that Reed-Sternberg cells from both nodular sclerosing and lymphocyte predominant Hodgkin's disease were derived from an unusual B-cell lineage based on a comparison of their gene expression to approximately 40,000,000 bases (10(5) sequences) of expressed gene sequence from germinal center B cells (GCB) and dendritic cells. The data set of expressed genes, reported here and on the World Wide Web, forms a basis to understand the genes responsible for Hodgkin's disease and develop novel diagnostic markers and therapies. This study of the rare Reed-Sternberg cell, concealed in its heterogenous cellular context, also provides a formidable test case to advance the limit of analysis of differential gene expression to the single disease cell.

B-Lymphocytes↗
PubMed1999

Posttherapy surveillance of B-cell precursor acute lymphoblastic leukemia. Value of polymerase chain reaction and limitations of flow cytometry.

Flow cytometric immunophenotypic analysis is critical in diagnosis and classification of acute leukemia and has been used after therapy to monitor for minimal residual disease. However, the presence of normal B-cell precursors, hematogones, particularly in the context of treated pediatric B-cell precursor acute lymphoblastic leukemia (BP-ALL), may confound such evaluation. In this study, the value of more specific genotypic markers (polymerase chain reaction evaluation of 2 antigen receptor genes) was assessed to resolve this issue. Flow cytometric analysis of enriched mononuclear cells revealed 1% to 20% precursor B cells (PBCs), based on expression of 1 or more pan-B cell antigens in addition to CD10, CD34, and terminal deoxynucleotidyl transferase in all 14 patients studied. Inasmuch as this mimicked the immunophenotype of the original leukemic clone, PBCs, in isolation, were considered suspicious for minimal residual disease. However, 11 of the 14 posttherapy specimens (79%) revealed no monoclonally rearranged antigen receptor genes, and 7 of these 11 patients had trackable genotypic markers at presentation. Accordingly, by PCR these 7 patients had complete molecular remission, supported by clinical follow up of 16 to 73 months. Among the remaining 4 patients with PCR-negative disease, 3 continue in remission, confirming the interpretation of false-positive flow cytometric analysis. In conclusion, flow cytometric monitoring of posttherapy bone marrow specimens from patients with BP-ALL may be misleading, if considered in isolation, in falsely suggesting the presence of minimal residual disease. Rather, PCR for antigen receptor gene rearrangements is a valuable and specific tool, helpful in differentiating hematogones from minimal residual disease in patients with treated BP-ALL whose bone marrow harbors increased PBCs.

Adolescent↗
PubMed1998

Gene expression by single Reed-Sternberg cells: pathways of apoptosis and activation.

Although Hodgkin's disease is highly responsive to treatments that cause apoptosis, it remains resistant to the physiological mechanisms intended to cause cell death. Presumably, the Reed-Sternberg cell defies endogenous apoptosis, persists, accumulates, and manifests the malignant disorder seen clinically. The Reed-Sternberg cell expresses several members of the tumor necrosis factor receptor superfamily. This family of receptors is involved in both activation and proliferation of cells, as well as either protection from or initiation of apoptosis in cells expressing these surface proteins. Signals from these receptors affect transcription. We reasoned that the activation state and resistance to apoptosis of Reed-Sternberg cells might be attributable to dysregulation of genes controling these processes. To determine gene expression by Reed-Sternberg cells, we developed a method of micromanipulation, global reverse transcription, and the reverse transcription-polymerase chain reaction and applied it to 51 single Reed-Sternberg cells and their variants from six cases of Hodgkin's disease. This report analyzes the gene expression of bcl-xs, bcl-xl, bax-alpha, bax-beta, fadd, fas, fas ligand (fas L), ice, TNF-alpha, TNF-beta, TNFR1, TNFR2, TRAF1, TRAF2, TRAF3, cIAP2, and tradd at the level of mRNA in the single Reed-Sternberg cells and their variants. The findings here suggest a molecular mechanism for the activated state and in vivo survival occurring in untreated Reed-Sternberg cells of Hodgkin's disease.

Apoptosis↗
PubMed1998

TGF-beta 1 induces the cyclin-dependent kinase inhibitor p27Kip1 mRNA and protein in murine B cells.

TGF-beta1 inhibits the cell cycle progression of many types of cells by arresting them in the G1 phase. This cell cycle arrest has been attributed to the regulatory effects of TGF-beta1 on both the levels and the activities of the G1 cyclins and their kinase partners. The activities of these kinases are negatively regulated by a number of proteins, such as p15INK4b, p21WAF1/Cip1, and p27Kip1, that physically associate with cyclins, cyclin-dependent kinases (Cdk), or cyclin-Cdk complexes. In epithelial cell lines, TGF-beta1 was previously shown to inhibit cell cycle progression through down-regulation of Cdk4 and/or up-regulation of p15INK4b and/or p21WAF1/Cip1. However, TGF-beta1 had little or no effect on the p27Kip1 mRNA and protein levels. In this report, we show that, in contrast to observations in epithelial cell lines, TGF-beta1 increased the p27Kip1 mRNA and protein levels in the murine B cell lines CH31 and WEHI231. This TGF-beta1-mediated induction of p27Kip1 also resulted in an increased association of p27Kip1 with Cdk2 and a decreased Cdk2 kinase activity. In contrast to epithelial cells, however, TGF-beta1 had little or no effect on the Cdk4 and p21WAF1/Cip1 protein levels in these B cells. Finally, although several studies suggested a direct role of p53 in TGF-beta1-mediated cell cycle arrest in epithelial cells, TGF-beta1 inhibited cell cycle progression in CH31 even in the absence of wild-type p53. Taken together, these results suggest that TGF-beta1 induces G1 arrest in B cells primarily through a p53-independent up-regulation of p27Kip1 protein.

Animals↗
PubMed1998

Precursor B-Lymphoblastic lymphoma presenting as a solitary bone tumor and mimicking Ewing's sarcoma: a report of four cases and review of the literature.

Precursor B-lymphoblastic lymphoma (B-LBL) may present as a solitary bone tumor. Fewer than 10 cases with a proven precursor B-cell phenotype have been reported in the English literature. In this report, we describe four cases of B-lymphoblastic lymphoma presenting as a localized intraosseous mass, which clinically and histologically mimicked Ewing's sarcoma. Three tumors occurred in the tibia and one in the humerus. In all four cases, the initial diagnosis was either "Ewing's sarcoma" or "consistent with Ewing's sarcoma." All four patients were female. Three were children and one was an adult; mean age was 12.5 years (range, 4 to 31 years). All had extremity pain without significant constitutional symptoms. In three cases, the tumors were osteolytic on radiographic evaluation, and in one case, osteosclerotic. Immunohistochemical stains on paraffin-embedded tissue showed that the neoplastic cells expressed terminal deoxynucleotidyl transferase, CD43, vimentin, and CD99 (MIC2 gene product) in all cases. Three cases were negative for CD45. CD79a was positive in all four cases studied; however, CD20 (L26) was positive in only two of four cases. CD3 was negative in all cases. Two cases showed focal granular cytoplasmic staining for keratin. Two cases analyzed by polymerase chain reaction (PCR) revealed clonal rearrangement of the immunoglobulin heavy chain (IgH) gene. Follow-up revealed that the three pediatric patients, who received a high-dose multiagent chemotherapy regime for LBL, are disease free at follow-up intervals of more than 1, 11, and 12 years, respectively. The adult patient died two years after diagnosis with disseminated disease. Although rare, B-lymphoblastic lymphoma should be considered in the differential diagnosis of small round cell tumors of bone. A diagnosis of Ewing's sarcoma should be made only after complete immunophenotyping and, if necessary, molecular diagnostic tests to exclude lymphoblastic lymphoma. A limited panel of antibodies can lead to an erroneous diagnosis; B-lymphoblastic lymphoma may be negative for CD45 and CD20 but positive for CD99 and even for keratin, mimicking Ewing's sarcoma. Correct diagnosis is extremely important because LBL usually is curable in the pediatric age group with appropriate therapy.

Adult↗
PubMed1998

Reed-Sternberg cell: survival in a hostile sea.

In contrast to the non-Hodgkin's lymphomas, little is known regarding the origin, genetics, and function of the Reed-Sternberg cell of Hodgkin's disease. Unlike other cancers, the neoplastic cell of Hodgkin's disease, the Reed-Sternberg cell, is vastly outnumbered by a surrounding intense inflammatory infiltrate. How this rare neoplastic cell originates, persists, and disseminates in a presumably hostile cellular environment has remained a mystery. Understanding the biology of the Reed-Sternberg cell has been impeded by the rarity of the cell in tumor tissue. Herein, we describe how the application of single-cell genetic analysis has revealed a clonal and, possibly, germinal center B-cell origin of the Reed-Sternberg cell. By phenotype and function, Reed-Sternberg cells are highly interactive with their cellular microenvironment through cell-cell adhesion, expression of members of the tumor necrosis factor receptor superfamily, and elaboration of cytokines. Perhaps by their mimicry of immune system cells with antigen-presenting function, Reed-Sternberg cells mediate the unusual clinical and pathologic features of Hodgkin's disease: intense tissue inflammatory infiltrate, fibrosis, and constitutional symptoms.

Antigen-Presenting Cells↗
PubMed1997

Intravascular large cell lymphoma coexisting within hemangiomas of the skin.

Intravascular lymphomatosis is a rare and peculiar subtype of large cell lymphoma. The authors present the pathologic, clinical, and radiologic findings of a patient with intravascular large cell lymphoma coexisting within hemangiomas of the skin. Initially the lymphoma was clinically confined to the hemangiomas and the patient was closely observed for disease progression. Within 10 months the patient developed disseminated lymphoma involving both adrenals. A clinical remission was achieved, but the patient soon relapsed, and despite further chemotherapy he died with disseminated disease 23 months after the initial diagnosis. This report presents the only known case of an intravascular large cell lymphoma coexisting within a vascular lesion and highlights the potential aggressive nature of intravascular lymphomas.

Adrenal Gland Neoplasms↗
PubMed1997

Molecular detection of bone marrow involvement in intravascular lymphomatosis.

Intravascular lymphomatosis (IVL) is an extremely rare variant of aggressive non-Hodgkin's lymphoma characterized by confinement of neoplastic lymphocytes within vascular spaces. Although IVL is potentially curable with combination chemotherapy, diagnosis is often delayed, in part owing to the negative bone marrow biopsy specimens that are typical of this disorder. We hypothesized that use of a more sensitive method of analysis might identify small clonal B-cell populations in histologically negative bone marrow biopsy specimens from patients with IVL. With use of a recently described assay for immunoglobulin heavy chain gene rearrangement based on the polymerase chain reaction, we demonstrated clonal B-cell populations in histologically negative marrow specimens from five (100%) of five patients with IVL. None of these specimens demonstrated molecular evidence of the t(14;18) associated with follicular lymphoma, providing no evidence for a common derivation of IVL and follicular lymphoma. In summary, molecular analysis of routine bone marrow biopsy sepcimens from patients in whom the diagnosis of IVL is entertained may facilitate prompt recognition of a lympho-proliferative disorder and thereby permit timely therapeutic intervention. Moreover, these findings suggest that despite histologically negative staging bone marrow biopsy specimens, IVL typically disseminates early in its course, thus arguing against the use of localized therapy in this disorder.

Aged↗
PubMed1996

TPA-induced arrest of erythroid differentiation is coupled with downregulation of GATA-1 and upregulation of GATA-2 in an erythroid cell line SAM-1.

GATA-1 protein is thought to be a positive regulator of erythroid differentiation. However, ectopic expression of a conditional GATA-2/estrogen receptor chimera was shown to inhibit erythroid differentiation in a hormone-dependent manner, suggesting the negative regulation of erythroid differentiation by GATA-2 protein. Accordingly, we reasoned that the quantitative balance of GATA-1 and GATA-2 protein might affect erythroid differentiation. In this report, we performed specific and quantitative measurements of GATA-1 and GATA-2 protein in a new erythroid cell line, SAM-1, after treatment with 12-O-tetradecanoylphorbol 13-acetate (TPA). On the basis of these measurements, we show that TPA-induced arrest of erythroid differentiation is coupled with the upregulation of GATA-2 protein, as well as the downregulation of GATA-1 protein. Our results suggest that it is the precise quantitative balance of GATA-1 and GATA-2 protein that regulates erythroid differentiation.

Antigens, Differentiation↗
PubMed1996

Expression of Bcl-x in T cells.

The thymus is a major site of apoptosis where programmed cell death is involved in the deletion of self-reactive T cells. We have investigated the role of bcl-x in T cells by defining the expression of its two isoforms, bcl-x and bcl-xs, in a series of human thymocyte cell lines and in human T lymphocytes using the ribonuclease protection assay. Bcl-x1 was the predominant isoform expressed in T cell lines and in T lymphocytes, where expression was further enhanced by PMA/ionomycin. This broad expression supports a central role for bcl-x in thymocyte development perhaps through post-transcriptional regulation.

Apoptosis↗
PubMed1996

T-cell-rich B-cell lymphoma presenting in skin. A clinicopathologic analysis of six cases.

We reviewed our experience with six T-cell-rich B-cell lymphomas (TRBL) presenting in skin. Immunohistochemical studies were performed on all biopsies. The lymphoid population consisted mainly of CD3 and/or UCHL-1 (CD45RO) positive T cells. 5 to 15% of the lymphoid cells stained for the B-cell marker L26 (CD20). Monoclonality of the B-cell component was demonstrated in all cases, utilizing either light chain restriction (5 cases) or clonal immunoglobulin heavy chain gene rearrangement by polymerase chain reaction (PCR) (2 cases). One case was confirmed to be monoclonal by both techniques. Additionally, no clonal rearrangements of the T-cell receptor gamma gene were observed. There was considerable morphological variety in these cases. In H&E stained sections, the differential diagnosis included pseudolymphoma, peripheral T-cell lymphoma, Hodgkin's disease, Lennert's lymphoma and a MALT lymphoma. A significant component of monoclonal plasma cells was present in 3 of 6 cases, suggesting a possible origin from cutaneous immunocytoma. In fact, one of our cases was a biphasic lymphoma displaying TRBL with a small focus of immunocytoma. We conclude that immunophenotypic analysis is necessary for the diagnosis of TRBL. Pathologists should be aware of this type of cutaneous B-cell lymphoma to avoid misinterpretation as a pseudolymphoma.

Adult↗
PubMed1996

Molecular genetic biomarkers in hematological malignancies.

Most hematopoietic malignancies are widely disseminated even in their "early" stages and often do not have a well-defined localized phase. This makes them less amenable to conventional early screening methods such as imaging and observation. Furthermore, the staging systems for lymphomas are not particularly useful prognostically, with the possible exception of Hodgkin's disease. However, as currently compared with solid tumors, the extensively detailed understanding of the acquired (somatic) genetic lesions in leukemias and lymphomas provide useful molecular biomarkers for early detection. Moreover, well described high risk groups have been identified. These include individuals who are immunosuppressed, for example, iatrogenically following organ transplantation or those with AIDS. Also at high risk are patients treated with certain chemotherapeutic agents who are at risk for the development of acute non-lymphoblastic leukemia. Accordingly, these clinical settings might prove to be good models for evaluating molecular cancer risk markers and the possible introduction of chemoprevention. Here, we outline the biological basis for the application of biomarkers for the early detection of hematological neoplasia. These concepts may provide the stage for the creation of chemoprevention studies in leukemia and lymphoma.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Human immunodeficiency virus 1 envelope-initiated G2-phase programmed cell death.

Despite intensive investigation, no clearly defined mechanism explaining human immunodeficiency virus (HIV)-induced cell killing has emerged. HIV-1 infection is initiated through a high-affinity interaction between the HIV-1 external envelope glycoprotein (gp120) and the CD4 receptor on T cells. Cell killing is a later event intimately linked by in vitro genetic analyses with the fusogenic properties of the HIV envelope glycoprotein gp120 and transmembrane glycoprotein gp41. In this report, we describe aberrancies in cell cycle regulatory proteins initiated by cell-cell contact between T cells expressing HIV-1 envelope glycoproteins and other T cells expressing CD4 receptors. Cells rapidly accumulate cyclin B protein and tyrosine-hyperphosphorylated p34cdc2 (cdk1) kinase, indicative of cell cycle arrest at G2 phase. Moreover, these cells continue to synthesize cyclin B protein, enlarge and display an abnormal ballooned morphology, and disappear from the cultures in a pattern previously described for cytotoxicity induced by DNA synthesis (S phase) inhibitors. Similar changes are observed in peripheral blood mononuclear cells infected in vitro with pathogenic primary isolates of HIV-1.

Apoptosis↗
PubMed1995

Polymerase chain reaction versus Southern blot hybridization. Detection of immunoglobulin heavy-chain gene rearrangements.

To determine efficiently the clonality of B-cell lymphoproliferative disorders, we modified an immunoglobulin heavy-chain (IGH) gene rearrangement polymerase chain reaction (PCR) assay that requires only a single primer germline variable (VH) and joining (JH) pair and does not involve nested priming, blot hybridization, radioactivity, or sequencing of the amplified PCR product. This simple PCR technique enabled detection of IGH gene rearrangements in as little as 10 pg (one cell equivalent) of DNA or when the clonal-to-polyclonal B-cell ratio was experimentally set at 1:1000. We detected IGH gene rearrangements in 83.5% (71 of 85) of clonal B-cell processes, a sensitivity approaching that of more cumbersome multiple primer and nested primer assays. Moreover, this technique is equally effective with fixed tissues, either B5 or formalin, and can be performed on minute samples, histologic sections, fine-needle aspirates, or cerebrospinal fluids. When compared with conventional Southern blot analysis using a genomic JH probe, the PCR assay demonstrated IGH gene rearrangements in 82% (37 of 45) of B-cell processes positive by Southern blot. No false-positive results were observed in 29 negative control tissues. We now use IGH gene PCR routinely in our laboratory for the detection of clonal B-cells in virtually any tissue sample as an aid in early diagnosis, staging, and monitoring, and the Southern blot procedure is reserved for only a minority of diagnostic cases. for only a minority of diagnostic cases.

B-Lymphocytes↗
PubMed1994

Role of bcl-2 and IL-5 in the regulation of anti-IgM-induced growth arrest and apoptosis in immature B cell lines. A cooperative regulation model for B cell clonal deletion.

Recent studies of transgenic mice have confirmed that clonal deletion is involved in the development of B cells. However, little is known about intercellular and intracellular molecular events regulating B cell clonal deletion. We investigated the role of bcl-2 and cytokines in the regulation of B cell clonal deletion using anti-IgM-induced growth arrest and apoptosis in immature B cell lines as a model. We show here that overexpression of Bcl-2 protein in stably transfected immature B cells partially inhibits anti-Ig M-induced apoptosis but does not affect growth arrest. Similarly, IL-5 has a strong inhibitory effect on anti-IgM-mediated apoptosis but has a weak inhibitory effect on growth arrest. Finally, although both bcl-2 overexpression and exogenous IL-5 cooperate with bacterial LPS to block apoptosis, bcl-2 overexpression and exogenous IL-5 have no additive inhibitory effect on anti-Ig induced apoptosis. These findings indicate that anti-IgM-induced apoptosis is independently regulated from growth arrest and is controlled by at least two independent pathways: One is regulated by either Bcl-2 protein or IL-5 and the other is regulated by LPS. Activation of both the bcl-2/IL-5 and LPS pathways is necessary for complete inhibition of apoptosis, and presumably, clonal selection of the immature B cells.

Animals↗
PubMed1993

bcl-2 protein inhibits etoposide-induced apoptosis through its effects on events subsequent to topoisomerase II-induced DNA strand breaks and their repair.

Previous studies have shown that bcl-2 overexpression can inhibit apoptosis induced by DNA-damaging agents widely used in cancer chemotherapy, including X-irradiation, alkylating agents (hydroperoxycyclophosphamide, etc.), and topoisomerase II inhibitors (etoposide, etc.). However, little is known about the mechanism by which bcl-2 overexpression inhibits apoptosis triggered by these agents. In this study, we examined whether bcl-2 overexpression could have effects on etoposide-induced DNA damage and its repair. For these experiments, we developed CH31 clones (mouse B-cells) stably transfected with human bcl-2 sense plasmids and compared these clones with a parental CH31 clone or CH31 clones with antisense plasmids. Overexpression of bcl-2 protein inhibited etoposide-induced apoptosis and cytotoxicity. However, there was no or little difference in the production and repair of DNA-protein cross-links, DNA single-strand breaks, and double-strand beaks among a parental CH31 clone and CH31 clones with human bcl-2 sense or antisense plasmids. These findings indicate that (a) apoptosis or cytotoxicity induced by etoposide can be separated into early events (formation of double-strand breaks, DNA single-strand breaks, and double-strand breaks) and later events (secondary DNA fragmentation or cell death) and (b) bcl-2 inhibits apoptosis and cytotoxicity induced by etoposide at some steps between these events.

Animals↗