Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients infected with human immunodeficiency virus type 1 (HIV-1) develop a spectrum of B cell lymphoproliferative disorders ranging from polyclonal B cell activation to B cell lymphomas. While a direct role of Epstein-Barr virus (EBV) is well recognized for most of these lesions, recent findings have suggested that transactivator HIV-1 Tat protein might be involved in the pathogenesis of B cell lymphomas. Tat-expressing EBV-positive B cells were generated by transduction with a retroviral Tat-encoding vector. B(Tat+) cells expressed lower levels of anti-apoptotic protein Bcl-2 than parental and control B(Tat-) cells, generated by transduction with an empty retroviral vector, and were more prone to apoptosis upon serum withdrawal, as assessed by analysis of annexin V-stained cells and cleavage of poly-ADP-ribose-polymerase by caspase 3. Nevertheless, in serum starvation, B(Tat-) cells mainly exhibited the Rb hypo-phosphorylated form, underwent cell cycle arrest, and grew in single cell suspension, while B(Tat+) cells displayed the Rb hyper-phoshorylated form, progressed throughout the cell cycle, and retained the ability to grow in small clumps. Finding that B(Tat+) cells maintained proliferative capacity upon serum withdrawal suggests that cells expressing Tat have growth advantages among the EBV-driven cell proliferations and may originate B cell clones with more oncogenic potential.
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PMID:Human immunodeficiency virus type 1 Tat protein modulates cell cycle and apoptosis in Epstein-Barr virus-immortalized B cells. 1509 50

A variety of nonmalignant cells present in the tumor microenvironment promotes tumorigenesis by stimulating tumor cell growth and metastasis or suppressing host immunity. The role of such stromal cells in T-cell lymphoproliferative disorders is incompletely understood. Monocyte-derived cells (MDCs), including professional antigen-presenting cells such as dendritic cells (DCs), play a central role in T-cell biology. Here, we provide evidence that monocytes promote the survival of malignant T cells and demonstrate that MDCs are abundant within the tumor microenvironment of T cell-derived lymphomas. Malignant T cells were observed to remain viable during in vitro culture with autologous monocytes, but cell death was significantly increased after monocyte depletion. Furthermore, monocytes prevent the induction of cell death in T-cell lymphoma lines in response to either serum starvation or doxorubicin, and promote the engraftment of these cells in nonobese diabetic/severe combined immunodeficient mice. Monocytes are actively recruited to the tumor microenvironment by CCL5 (RANTES), where their differentiation into mature DCs is impaired by tumor-derived interleukin-10. Collectively, the data presented demonstrate a previously undescribed role for monocytes in T-cell lymphoproliferative disorders.
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PMID:Monocytes promote tumor cell survival in T-cell lymphoproliferative disorders and are impaired in their ability to differentiate into mature dendritic cells. 1967 21