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Neoplasia and paracoccidioidomycosis

SHIKANAI-YASUDA, M. A.; CONCEICAO, Y. M. T.; KONO, A.; RIVITTI, E.; CAMPOS, A. F.; CAMPOS, S. V.
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.27%
Published studies on the association between cancer and paracoccidioidomycosis consist either isolated cases or clinical data based on hospital cohorts of paracoccidioidomycosis. The frequency of neoplasia in series of >= 80 patients with paracoccidioidomycosis ranges from 0.16 to 14.1%, mean of 3.96%. There are only two retrospective controlled studies, one of them showing greater incidence of carcinoma in biopsy and necropsy samples of paracoccidioidomycosis (12 cases in 147 patients with the mycosis: 8.2%) than in the necropsies of the control group (320 cases in 7,302 necropsies: 4.9%). In the other, 22,409 autopsies were reviewed and 4,372 cases of cancer were found; of the 85 patients with paracoccidioidomycosis, 12 were diagnosed with cancer. No differences were observed in the frequency of malignancies between the group of patients with paracoccidioidomycosis (14.1%) and the control group (19.5%). Considering all the reported cases, carcinoma was more frequent than hematological malignancies, and was more often found at the same site or in a neighboring site affected by the mycosis, usually occurring after the diagnosis of the mycosis. Commonly, the basic cause of death was related to secondary infections or neoplasia. Lymphoma was associated with poorly organized rich in fungi granuloma. The clinical course and mortality were related to the cancer evolution or secondary infections and was worse in lymphoid series...

Rapid, nonradioactive detection of clonal T-cell receptor gene rearrangements in lymphoid neoplasms.

Bourguin, A; Tung, R; Galili, N; Sklar, J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1990 Português
Relevância na Pesquisa
36.23%
Southern blot hybridization analysis of clonal antigen receptor gene rearrangements has proved to be a valuable adjunct to conventional methods for diagnosing lymphoid neoplasia. However, Southern blot analysis suffers from a number of technical disadvantages, including the time necessary to obtain results, the use of radioactivity, and the susceptibility of the method to various artifacts. We have investigated an alternative approach for assessing the clonality of antigen receptor gene rearrangements in lymphoid tissue biopsy specimens. This approach involves the amplification of rearranged gamma T-cell receptor genes by the polymerase chain reaction and analysis of the polymerase chain reaction products by denaturing gradient gel electrophoresis. By use of this approach, clonal rearrangements from neoplastic lymphocytes constituting as little as 0.1-1% of the total cells in the tissue are detected as discrete bands in the denaturing gel after the gel is stained with ethidium bromide and viewed under ultraviolet light. In contrast, polyclonal rearrangements from reactive lymphocytes appear as a diffuse smear along the length of the gel. Our findings suggest that polymerase chain reaction combined with denaturing gradient gel electrophoresis may offer a rapid...

Manifold expression of new cellular genes in human lymphoid neoplasia.

Hanania, N; Shaool, D; Poncy, C; Harel, J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1981 Português
Relevância na Pesquisa
36.44%
Previous studies performed in our laboratory have shown that a minor single-stranded DNA component (ssDNA) isolated from the bulk of double-stranded nuclear DNA (nDNA) of human, murine, or avian cells consisted mainly of active transcription sites. In the present work, ssDNA isolated from human lymphoid cells, either malignant or not, amounted to 1.2-1.4% of the total nDNA. This was labeled with 125I and utilized as a probe in RNA-driven iterative hybridization and cross-hybridization assays. In all cases of neoplasia studied, the same subfraction of ssDNA (equivalent to 10-12% of the total ssDNA) from malignant cells could be hybridized with cytoplasmic RNA from malignant cells, whatever their origin: acute lymphoid leukemia cells collected from blood of leukemic patients, local lymphosarcomas, or cells from two established strains grown in suspension, one Epstein-Barr virus positive (Raji strain), the other Epstein--Barr virus negative (Ramos strain). The majority of these tumor-specific DNA sequences could be reassociated with unique-copy DNA from both normal and malignant cells and were not expressed in normal lymphoid cells, including those of an established strain immortalized by Epstein--Barr virus and multiplied in culture. It is concluded that a great number of new transcription units...

Uveal lymphoid infiltrates: immunohistochemical evidence for a lymphoid neoplasia.

Ben-Ezra, D; Sahel, J A; Harris, N L; Hemo, I; Albert, D M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1989 Português
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36.17%
A 67-year-old man presented with a diffuse choroidal and ciliary body infiltrate, suggesting clinically and ultrasonographically a diffuse uveal melanoma. After enucleation both morphological and immunohistochemical data were highly suggestive of a diffuse, low-grade B cell lymphoma or lymphoplasmacytic immunocytoma. The difficulties of clinical and histopathological differential diagnosis of uveal lymphoid infiltrates are emphasised. In view of the excellent life prognosis of these tumours, treatment of the patient should be directed towards the preservation of ocular function.

MN1-TEL myeloid oncoprotein expressed in multipotent progenitors perturbs both myeloid and lymphoid growth and causes T-lymphoid tumors in mice

Kawagoe, Hiroyuki; Grosveld, Gerard C.
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 15/12/2005 Português
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36.26%
The MN1-TEL (meningioma 1-translocation-ETS-leukemia) fusion oncoprotein is the product of the t(12;22)(p13;q11) in human myeloid leukemia consisting of N-terminal MN1 sequences, a transcriptional coactivator, fused to C-terminal TEL sequences, an E26-transformation–specific (ETS) transcription factor. To analyze the role of MN1-TEL in leukemogenesis, we created a site-directed transgenic (knock-in) mouse model carrying a conditional MN1-TEL transgene under the control of the Aml1 regulatory sequences. After induction, MN1-TEL expression was detected in both myeloid and lymphoid cells. Activation of MN1-TEL expression enhanced the repopulation ability of myeloid progenitors in vitro as well as partially inhibited their differentiation in vivo. MN1-TEL also promoted the proliferation of thymocytes while it blocked their differentiation from CD4-/CD8- to CD4+/CD8+ in vivo. After long latency, 30% of the MN1-TEL–positive mice developed T-lymphoid tumors. This process was accelerated by N-ethyl-N-nitrosourea–induced mutations. MN1-TEL–positive T-lymphoid tumors showed elevated expression of the Notch-1, Hes-1, c-Myc, and Lmo-2 genes while their Ink4a/pRB and Arf/p53 pathways were impaired, suggesting that these alterations cooperatively transform T progenitors. We conclude that MN1-TEL exerts its nonlineage-specific leukemogenic effects by promoting the growth of primitive progenitors and blocking their differentiation...

A murine Mll-AF4 knock-in model results in lymphoid and myeloid deregulation and hematologic malignancy

Chen, Weili; Li, Quanzhi; Hudson, Wendy A.; Kumar, Ashish; Kirchhof, Nicole; Kersey, John H.
Fonte: The American Society of Hematology Publicador: The American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 15/07/2006 Português
Relevância na Pesquisa
36.31%
The 2 most frequent human MLL hematopoietic malignancies involve either AF4 or AF9 as fusion partners; each has distinct biology but the role of the fusion partner is not clear. We produced Mll-AF4 knock-in (KI) mice by homologous recombination in embryonic stem cells and compared them with Mll-AF9 KI mice. Young Mll-AF4 mice had lymphoid and myeloid deregulation manifest by increased lymphoid and myeloid cells in hematopoietic organs. In vitro, bone marrow cells from young mice formed unique mixed pro-B lymphoid (B220+CD19+CD43+sIgM–, PAX5+, TdT+, IgH rearranged)/myeloid (CD11b/Mac1+, c-fms+, lysozyme+) colonies when grown in IL-7– and Flt3 ligand-containing media. Mixed lymphoid/myeloid hyperplasia and hematologic malignancies (most frequently B-cell lymphomas) developed in Mll-AF4 mice after prolonged latency; long latency to malignancy indicates that Mll-AF4–induced lymphoid/myeloid deregulation alone is insufficient to produce malignancy. In contrast, young Mll-AF9 mice had predominately myeloid deregulation in vivo and in vitro and developed myeloid malignancies. The early onset of distinct mixed lymphoid/myeloid lineage deregulation in Mll-AF4 mice shows evidence for both “instructive” and “noninstructive” roles for AF4 and AF9 as partners in MLL fusion genes. The molecular basis for “instruction” and secondary cooperating mutations can now be studied in our Mll-AF4 model.

Proposed classification of lymphoid neoplasms for epidemiologic research from the Pathology Working Group of the International Lymphoma Epidemiology Consortium (InterLymph)

Morton, Lindsay M.; Turner, Jennifer J.; Cerhan, James R.; Linet, Martha S.; Treseler, Patrick A.; Clarke, Christina A.; Jack, Andrew; Cozen, Wendy; Maynadié, Marc; Spinelli, John J.; Costantini, Adele Seniori; Rüdiger, Thomas; Scarpa, Aldo; Zheng, Tong
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 15/07/2007 Português
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36.31%
Recent evidence suggests that there is etiologic heterogeneity among the various subtypes of lymphoid neoplasms. However, epidemiologic analyses by disease subtype have proven challenging due to the numerous clinical and pathologic schemes used to classify lymphomas and lymphoid leukemias over the last several decades. On behalf of the International Lymphoma Epidemiology Consortium (InterLymph) Pathology Working Group, we present a proposed nested classification of lymphoid neoplasms to facilitate the analysis of lymphoid neoplasm subtypes in epidemiologic research. The proposed classification is based on the World Health Organization classification of lymphoid neoplasms and the International Classification of Diseases–Oncology, Third Edition (ICD-O-3). We also provide a translation into the proposed classification from previous classifications, including the Working Formulation, Revised European-American Lymphoma (REAL) classification, and ICD-O-2. We recommend that epidemiologic studies include analyses by lymphoma subtype to the most detailed extent allowable by sample size. The standardization of groupings for epidemiologic research of lymphoma subtypes is essential for comparing subtype-specific reports in the literature, harmonizing cases within a single study diagnosed using different systems...

Gene expression profiling of pulmonary mucosa-associated lymphoid tissue lymphoma identifies new biologic insights with potential diagnostic and therapeutic applications

Chng, Wee J.; Remstein, Ellen D.; Fonseca, Rafael; Bergsagel, P. Leif; Vrana, Julie A.; Kurtin, Paul J.; Dogan, Ahmet
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 15/01/2009 Português
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46.17%
We conducted comprehensive gene expression profiling (GEP) of primary pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma (n = 33) and compared the results to GEP of other B- and T-cell lymphomas and normal lymphocytes to identify novel markers and deregulated pathways. MALT has a prominent T-cell signature and a marginal zone/memory B-cell profile. Four novel transcripts were specifically overexpressed in MALT, and 2 of these, MMP7 and SIGLEC6, were validated at the protein level. GEP also revealed distinct molecular subsets in MALT. One subset, characterized by MALT1 translocations, showed overexpression of nuclear factor-κB (NF-KB) pathway genes but also was enriched for chemokine signaling pathways. Another subset showed increased plasma cells and a prominent plasma cell gene signature. By analyzing several genes with very high (“spiked”) expression in individual cases, we identified clusters with different biologic characteristics, such as samples with MALT1 translocations having high expression of MALT1 and RARA, samples with plasmacytic differentiation having high FKBP11 expression, and samples with high RGS13 expression tending to have trisomy 3 and reactive follicles. In conclusion, MALT subgroups with distinct pathologic features defined by distinct groups of deregulated genes were identified. These genes could represent novel diagnostic and therapeutic targets.

Ectopic expression of B-lymphoid kinase in cutaneous T-cell lymphoma

Krejsgaard, Thorbjørn; Vetter-Kauczok, Claudia S.; Woetmann, Anders; Kneitz, Hermann; Eriksen, Karsten W.; Lovato, Paola; Zhang, Qian; Wasik, Mariusz A.; Geisler, Carsten; Ralfkiaer, Elisabeth; Becker, Juergen C.; Ødum, Niels
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 04/06/2009 Português
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46.23%
B-lymphoid kinase (Blk) is exclusively expressed in B cells and thymocytes. Interestingly, transgenic expression of a constitutively active form of Blk in the T-cell lineage of mice results in the development of T-lymphoid lymphomas. Here, we demonstrate nuclear factor–kappa B (NF-κB)–mediated ectopic expression of Blk in malignant T-cell lines established from patients with cutaneous T-cell lymphoma (CTCL). Importantly, Blk is also expressed in situ in lesional tissue specimens from 26 of 31 patients with CTCL. Already in early disease the majority of epidermotropic T cells express Blk, whereas Blk expression is not observed in patients with benign inflammatory skin disorders. In a longitudinal study of an additional 24 patients biopsied for suspected CTCL, Blk expression significantly correlated with a subsequently confirmed diagnosis of CTCL. Blk is constitutively tyrosine phosphorylated in malignant CTCL cell lines and spontaneously active in kinase assays. Furthermore, targeting Blk activity and expression by Src kinase inhibitors and small interfering RNA (siRNA) inhibit the proliferation of the malignant T cells. In conclusion, this is the first report of Blk expression in CTCL, thereby providing new clues to the pathogenesis of the disease.

Kinome-wide RNAi studies in human multiple myeloma identify vulnerable kinase targets, including a lymphoid-restricted kinase, GRK6

Tiedemann, Rodger E.; Zhu, Yuan Xiao; Schmidt, Jessica; Yin, Hongwei; Shi, Chang-Xin; Que, Qiang; Basu, Gargi; Azorsa, David; Perkins, Louise M.; Braggio, Esteban; Fonseca, Rafael; Bergsagel, P. Leif; Mousses, Spyro; Stewart, A. Keith
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 25/02/2010 Português
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46.17%
A paucity of validated kinase targets in human multiple myeloma has delayed clinical deployment of kinase inhibitors in treatment strategies. We therefore conducted a kinome-wide small interfering RNA (siRNA) lethality study in myeloma tumor lines bearing common t(4;14), t(14;16), and t(11;14) translocations to identify critically vulnerable kinases in myeloma tumor cells without regard to preconceived mechanistic notions. Fifteen kinases were repeatedly vulnerable in myeloma cells, including AKT1, AK3L1, AURKA, AURKB, CDC2L1, CDK5R2, FES, FLT4, GAK, GRK6, HK1, PKN1, PLK1, SMG1, and TNK2. Whereas several kinases (PLK1, HK1) were equally vulnerable in epithelial cells, others and particularly G protein–coupled receptor kinase, GRK6, appeared selectively vulnerable in myeloma. GRK6 inhibition was lethal to 6 of 7 myeloma tumor lines but was tolerated in 7 of 7 human cell lines. GRK6 exhibits lymphoid-restricted expression, and from coimmunoprecipitation studies we demonstrate that expression in myeloma cells is regulated via direct association with the heat shock protein 90 (HSP90) chaperone. GRK6 silencing causes suppression of signal transducer and activator of transcription 3 (STAT3) phosphorylation associated with reduction in MCL1 levels and phosphorylation...

InterLymph hierarchical classification of lymphoid neoplasms for epidemiologic research based on the WHO classification (2008): update and future directions

Turner, Jennifer J.; Morton, Lindsay M.; Linet, Martha S.; Clarke, Christina A.; Kadin, Marshall E.; Vajdic, Claire M.; Monnereau, Alain; Maynadié, Marc; Chiu, Brian C.-H.; Marcos-Gragera, Rafael; Costantini, Adele Seniori; Cerhan, James R.; Weisenburger
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 18/11/2010 Português
Relevância na Pesquisa
46.23%
After publication of the updated World Health Organization (WHO) classification of tumors of hematopoietic and lymphoid tissues in 2008, the Pathology Working Group of the International Lymphoma Epidemiology Consortium (InterLymph) now presents an update of the hierarchical classification of lymphoid neoplasms for epidemiologic research based on the 2001 WHO classification, which we published in 2007. The updated hierarchical classification incorporates all of the major and provisional entities in the 2008 WHO classification, including newly defined entities based on age, site, certain infections, and molecular characteristics, as well as borderline categories, early and “in situ” lesions, disorders with limited capacity for clinical progression, lesions without current International Classification of Diseases for Oncology, 3rd Edition codes, and immunodeficiency-associated lymphoproliferative disorders. WHO subtypes are defined in hierarchical groupings, with newly defined groups for small B-cell lymphomas with plasmacytic differentiation and for primary cutaneous T-cell lymphomas. We suggest approaches for applying the hierarchical classification in various epidemiologic settings, including strategies for dealing with multiple coexisting lymphoma subtypes in one patient...

Cytotoxicity of farnesyltransferase inhibitors in lymphoid cells mediated by MAPK pathway inhibition and Bim up-regulation

Ding, Husheng; Hackbarth, Jennifer; Schneider, Paula A.; Peterson, Kevin L.; Meng, X. Wei; Dai, Haiming; Witzig, Thomas E.; Kaufmann, Scott H.
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 03/11/2011 Português
Relevância na Pesquisa
46.29%
The mechanism of cytotoxicity of farnesyltransferase inhibitors is incompletely understood and seems to vary depending on the cell type. To identify potential determinants of sensitivity or resistance for study in the accompanying clinical trial (Witzig et al, page 4882), we examined the mechanism of cytotoxicity of tipifarnib in human lymphoid cell lines. Based on initial experiments showing that Jurkat variants lacking Fas-associated death domain or procaspase-8 undergo tipifarnib-induced apoptosis, whereas cells lacking caspase-9 or overexpressing Bcl-2 do not, we examined changes in Bcl-2 family members. Tipifarnib caused dose-dependent up-regulation of Bim in lymphoid cell lines (Jurkat, Molt3, H9, DoHH2, and RL) that undergo tipifarnib-induced apoptosis but not in lines (SKW6.4 and Hs445) that resist tipifarnib-induced apoptosis. Further analysis demonstrated that increased Bim levels reflect inhibition of signaling from c-Raf to MEK1/2 and ERK1/2. Additional experiments showed that down-regulation of the Ras guanine nucleotide exchange factor RasGRP1 diminished tipifarnib sensitivity, suggesting that H-Ras or N-Ras is a critical farnesylation target upstream of c-Raf in lymphoid cells. These results not only trace a pathway through c-Raf to Bim that contributes to tipifarnib cytotoxicity in human lymphoid cells but also identify potential determinants of sensitivity to this agent.

Dual mTORC1/mTORC2 inhibition diminishes Akt activation and induces Puma-dependent apoptosis in lymphoid malignancies

Gupta, Mamta; Hendrickson, Andrea E. Wahner; Yun, Seong Seok; Han, Jing Jing; Schneider, Paula A.; Koh, Brian D.; Stenson, Mary J.; Wellik, Linda E.; Shing, Jennifer C.; Peterson, Kevin L.; Flatten, Karen S.; Hess, Allan D.; Smith, B. Douglas; Karp, Judit
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 12/01/2012 Português
Relevância na Pesquisa
46.29%
The mammalian target of rapamycin (mTOR) plays crucial roles in proliferative and antiapoptotic signaling in lymphoid malignancies. Rapamycin analogs, which are allosteric mTOR complex 1 (mTORC1) inhibitors, are active in mantle cell lymphoma and other lymphoid neoplasms, but responses are usually partial and short-lived. In the present study we compared the effects of rapamycin with the dual mTORC1/mTORC2 inhibitor OSI-027 in cell lines and clinical samples representing divers lymphoid malignancies. In contrast to rapamycin, OSI-027 markedly diminished proliferation and induced apoptosis in a variety of lymphoid cell lines and clinical samples, including specimens of B-cell acute lymphocytic leukemia (ALL), mantle cell lymphoma, marginal zone lymphoma and Sezary syndrome. Additional analysis demonstrated that OSI-027–induced apoptosis depended on transcriptional activation of the PUMA and BIM genes. Overexpression of Bcl-2, which neutralizes Puma and Bim, or loss of procaspase 9 diminished OSI-027–induced apoptosis in vitro. Moreover, OSI-027 inhibited phosphorylation of mTORC1 and mTORC2 substrates, up-regulated Puma, and induced regressions in Jeko xenografts. Collectively, these results not only identify a pathway that is critical for the cytotoxicity of dual mTORC1/mTORC2 inhibitors...

Bmi1 reprograms CML B-lymphoid progenitors to become B-ALL–initiating cells

Sengupta, Amitava; Ficker, Ashley M.; Dunn, Susan K.; Madhu, Malav; Cancelas, Jose A.
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 12/01/2012 Português
Relevância na Pesquisa
46.31%
The characterization and targeting of Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL)–initiating cells remains unresolved. Expression of the polycomb protein Bmi1 is up-regulated in patients with advanced stages of chronic myelogenous leukemia (CML). We report that Bmi1 transforms and reprograms CML B-lymphoid progenitors into stem cell leukemia (Scl) promoter-driven, self-renewing, leukemia-initiating cells to result in B-lymphoid leukemia (B-ALL) in vivo. In vitro, highly proliferating and serially replatable myeloid and lymphoid colony-forming cultures could be established from BCR-ABL and Bmi1 coexpressing progenitors. However, unlike in vivo expanded CML B-lymphoid progenitors, hematopoietic stem cells, or multipotent progenitors, coexpressing BCR-ABL and Bmi1 did not initiate or propagate leukemia in a limiting dilution assay. Inducible genetic attenuation of BCR-ABL reversed Bmi1-driven B-ALL development, which was accompanied by induction of apoptosis of leukemic B-lymphoid progenitors and by long-term animal survival, suggesting that BCR-ABL is required to maintain B-ALL and that BCR-ABL and Bmi1 cooperate toward blast transformation in vivo. Our data indicate that BCR-ABL targeting itself is required to eradicate Ph+/Bmi1+ B-ALL–initiating cells and confirm their addiction to BCR-ABL signaling.

Bcl-2, Bcl-xL, and Bcl-w are not equivalent targets of ABT-737 and navitoclax (ABT-263) in lymphoid and leukemic cells

Mérino, Delphine; Khaw, Seong L.; Glaser, Stefan P.; Anderson, Daniel J.; Belmont, Lisa D.; Wong, Chihunt; Yue, Peng; Robati, Mikara; Phipson, Belinda; Fairlie, Walter D.; Lee, Erinna F.; Campbell, Kirsteen J.; Vandenberg, Cassandra J.; Cory, Suzanne; Ro
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 14/06/2012 Português
Relevância na Pesquisa
46.23%
The BH3-mimetic ABT-737 and an orally bioavailable compound of the same class, navitoclax (ABT-263), have shown promising antitumor efficacy in preclinical and early clinical studies. Although both drugs avidly bind Bcl-2, Bcl-xL, and Bcl-w in vitro, we find that Bcl-2 is the critical target in vivo, suggesting that patients with tumors overexpressing Bcl-2 will probably benefit. In human non-Hodgkin lymphomas, high expression of Bcl-2 but not Bcl-xL predicted sensitivity to ABT-263. Moreover, we show that increasing Bcl-2 sensitized normal and transformed lymphoid cells to ABT-737 by elevating proapoptotic Bim. In striking contrast, increasing Bcl-xL or Bcl-w conferred robust resistance to ABT-737, despite also increasing Bim. Cell-based protein redistribution assays unexpectedly revealed that ABT-737 disrupts Bcl-2/Bim complexes more readily than Bcl-xL/Bim or Bcl-w/Bim complexes. These results have profound implications for how BH3-mimetics induce apoptosis and how the use of these compounds can be optimized for treating lymphoid malignancies.

Vav3 collaborates with p190-BCR-ABL in lymphoid progenitor leukemogenesis, proliferation, and survival

Chang, Kyung Hee; Sanchez-Aguilera, Abel; Shen, Shuhong; Sengupta, Amitava; Madhu, Malav N.; Ficker, Ashley M.; Dunn, Susan K.; Kuenzi, Ashley M.; Arnett, Jorden L.; Santho, Rebecca A.; Agirre, Xabier; Perentesis, John P.; Deininger, Michael W.; Zheng, Yi
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 26/07/2012 Português
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46.23%
Despite the introduction of tyrosine kinase inhibitor therapy, the prognosis for p190-BCR-ABL+ acute lymphoblastic leukemia remains poor. In the present study, we present the cellular and molecular roles of the Rho GTPase guanine nucleotide exchange factor Vav in lymphoid leukemogenesis and explore the roles of Vav proteins in BCR-ABL–dependent signaling. We show that genetic deficiency of the guanine nucleotide exchange factor Vav3 delays leukemogenesis by p190-BCR-ABL and phenocopies the effect of Rac2 deficiency, a downstream effector of Vav3. Compensatory up-regulation of expression and activation of Vav3 in Vav1/Vav2–deficient B-cell progenitors increases the transformation ability of p190-BCR-ABL. Vav3 deficiency induces apoptosis of murine and human leukemic lymphoid progenitors, decreases the activation of Rho GTPase family members and p21-activated kinase, and is associated with increased Bad phosphorylation and up-regulation of Bax, Bak, and Bik. Finally, Vav3 activation only partly depends on ABL TK activity, and Vav3 deficiency collaborates with tyrosine kinase inhibitors to inhibit CrkL activation and impair leukemogenesis in vitro and in vivo. We conclude that Vav3 represents a novel specific molecular leukemic effector for multitarget therapy in p190-BCR-ABL–expressng acute lymphoblastic leukemia.

Monoclonal gammopathy of undetermined significance and risk of lymphoid and myeloid malignancies: 728 cases followed up to 30 years in Sweden

Turesson, Ingemar; Kovalchik, Stephanie A.; Pfeiffer, Ruth M.; Kristinsson, Sigurdur Y.; Goldin, Lynn R.; Drayson, Mark T.; Landgren, Ola
Fonte: American Society of Hematology Publicador: American Society of Hematology
Tipo: Artigo de Revista Científica
Publicado em 16/01/2014 Português
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46.17%
Free light chain ratio, M-protein concentration, and immunosuppression predict progression of MGUS to lymphoid malignancies.

Development and Evaluation of Approaches for Quantitative Optical Molecular Imaging of Neoplasia

Rosbach, Kelsey Jane
Fonte: Universidade Rice Publicador: Universidade Rice
Português
Relevância na Pesquisa
36.34%
This thesis develops and evaluates three approaches for quantitative molecularly-targeted optical imaging of neoplasia. The first approach focuses on widefield imaging of biomarkers near the tissue surface for early detection applications; this approach is demonstrated in freshly resected oral tissue. Most oral cancers are not detected until the disease has spread, but topical application of targeted imaging agents allows rapid visualization of biomarker expression, giving real-time, objective information. Epidermal growth factor receptor (EGFR) expression was quantified in patient samples using fluorescent epidermal growth factor. Dysplasia (n=4) and cancer (n=13) had an average 2.3-fold and 3.8-fold increase in signal compared to normal tissue. EGFR expression was assessed along with metabolic activity using a fluorescent glucose analog, 2-NBDG, in 9 patient samples. A classification algorithm using quantitative image features resulted in an area under the curve (AUC) of 0.83, though the main advantage of this technique may be to understand spatial heterogeneity of biomarker expression and how this correlates with disease. The next approach focuses on high-resolution optical imaging through a needle to detect metastases in lymphoid tissue for clinical staging applications; this approach is demonstrated in resected lymph nodes from breast cancer patients. These patients often require removal of nodes...

Analysis of Immunoglobulin and T Cell Receptor Gene Rearrangement in the Bone Marrow of Lymphoid Neoplasia Using BIOMED-2 Multiplex Polymerase Chain Reaction

Shin, Soyoung; Kim, Ah Hyun; Park, Joonhong; Kim, Myungshin; Lim, Jihyang; Kim, Yonggoo; Han, Kyungja; Lee, Sun Ah; Cho, Seok-Goo
Fonte: Ivyspring International Publisher Publicador: Ivyspring International Publisher
Tipo: Artigo de Revista Científica
Publicado em 31/08/2013 Português
Relevância na Pesquisa
46.57%
The evaluation of bone marrow (BM) involvement is important for diagnosis and staging in patients with lymphoid neoplasia. We evaluated of immunoglobulin (Ig) and/or T-cell receptor (TCR) gene rearrangements in the BM using the standardized BIOMED-2 multiplex PCR clonality assays and compared the results with microscopic findings such as histology and CD10, CD20, CD79a, CD3 and CD5 immunohistochemistry. A total of 151 samples were enrolled; 119 B cell neoplasia, 29 T cell neoplasia, and 3 Hodgkin's lymphoma. The molecular clonality assay and microscopic diagnosis were concordant in 66.9% (n=101) and discordant in 33.1 % (n=50). Ig/TCR gene clonality assay detected 43 cases of BM involvement which was not presented in the morphology. Two cases among them turned into microscopic BM involvement during a close follow up. Clonal TCR gene rearrangements were detected in 12.6% of B cell neoplasia and Ig gene rearrangement were found in 3.4% of T cell neoplasia. This molecular clonality assay is valuable particularly in diagnosing BM involvement of lymphoid neoplasia if it is morphologically uncertain. But it should be carefully interpreted because molecular clonality may be present in the reactive lymphoproliferation. Therefore, comprehensive analysis with morphologic analysis should be important to reach a final diagnosis.

Comparative analysis of the expression patterns of metalloproteinases and their inhibitors in breast neoplasia, sporadic colorectal neoplasia, pulmonary carcinomas and malignant non-Hodgkin's lymphomas in humans.

Kossakowska, A. E.; Huchcroft, S. A.; Urbanski, S. J.; Edwards, D. R.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em /06/1996 Português
Relevância na Pesquisa
36.23%
Matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of metalloproteinases, TIMPs) play essential roles in the remodelling of the extracellular matrix (ECM). Results of in vivo and in vitro studies suggest that the balance between MMPs and TIMPs is altered in neoplasia, contributing to the invasive and metastatic properties of malignant tumours. In this study we have analysed the expression of five MMP genes and TIMP-1 and TIMP-2 in 37 benign and malignant lesions of human breast using Northern blot analysis. MMP-9 (92 kDa gelatinase) and MMP-11 (stromelysin 3) were most consistently expressed by carcinomas. Based on detection of either MMP-9 or MMP-11 mRNAs, we were able to distinguish between malignant and benign disease with a predictive accuracy of 90% with 94% sensitivity and 85% specificity. Subsequently, these results were compared with results for carcinomas of colon and lung and malignant non-Hodgkin's lymphomas (NHL). Elevated MMP-9 and TIMP-1 expression was observed in all four systems. MMP-11 characterised all carcinomas as well as carcinomas in situ but was not detectable in NHL. Our data therefore argue that there are remarkably similar patterns of specific functions involved in ECM remodelling that correlate with malignancy in different human tumours of different histogenesis. However...