Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Disseminated Mycobacterium avium complex (MAC) infection is a rare but severe disease mostly seen in patients with AIDS. It has been previously described in patients suffering from other kinds of immunodeficiency (e.g. primary immunodeficiency diseases in children or hairy cell leukaemia). We report two cases of disseminated MAC disease in young women with extended granulomatosis that revealed a new form of severe immunodeficiency syndrome. Both clinical observations initially appeared to be very similar to WHIM syndrome (Warts, Hypogammaglobulinemia, Infection, Myelokathexis), a rare immunodeficiency disease correlated with CXC chemokine receptor 4 (CXCR4) mutation leading to an impaired internalization of the receptor upon its ligand CXCL12. We investigated the CXCR4 status of the lymphocytes in both patients and found a severe defect in CXCL12-promoted internalization but no mutation of its gene. Moreover, myelokathexis was not noted in bone marrow biopsies and therefore a diagnosis of WHIM syndrome could not be assessed. This immunodeficiency syndrome associated with CXCR4 dysfunction was responsible for severe MAC infection in our patients, with a fatal outcome in one case. It may be possible that these patients would have benefited from early antimycobacterial infection or azythromycin prophylaxis.
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PMID:Two cases of disseminated Mycobacterium avium infection associated with a new immunodeficiency syndrome related to CXCR4 dysfunctions. 2014 20

CXCR4(WHIM) somatic mutations are common Waldenstrom's Macroglobulinemia (WM), and are associated with clinical resistance to ibrutinib. We engineered WM cells to express the most common WHIM (Warts, Hypogammaglobulinemia, Infections and Myelokathexis), CXCR(S338X) mutation in WM. Following SDF-1a stimulation, CXCR4(S338X) WM cells exhibited decreased receptor internalization, enhanced and sustained AKT kinase (AKT) and extracellular regulated kinase (ERK) signaling, decreased poly (ADP-ribose) polymerase and caspase 3 cleavage, and decreased Annexin V staining versus CXCR4 wild-type (WT) cells. CXCR4(S338X)-related signaling and survival effects were blocked by the CXCR4 inhibitor AMD3100. SDF-1a-treated CXCR4(S338X) WM cells showed sustained AKT and ERK activation and decreased apoptotic changes versus CXCR4(WT) cells following ibrutinib treatment, findings which were also reversed by AMD3100. AKT or ERK antagonists restored ibrutinib-triggered apoptotic changes in SDF-1a-treated CXCR4(S338X) WM cells demonstrating their role in SDF-1a-mediated ibrutinib resistance. Enhanced bone marrow pAKT staining was also evident in CXCR4(WHIM) versus CXCR4(WT) WM patients, and remained active despite ibrutinib therapy in CXCR4(WHIM) patients. Last, CXCR4(S338X) WM cells showed varying levels of resistance to other WM relevant therapeutics, including bendamustine, fludarabine, bortezomib and idelalisib in the presence of SDF-1a. These studies demonstrate a functional role for CXCR4(WHIM) mutations, and provide a framework for investigation of CXCR4 inhibitors in WM.
Leukemia 2015 Jan
PMID:The WHIM-like CXCR4(S338X) somatic mutation activates AKT and ERK, and promotes resistance to ibrutinib and other agents used in the treatment of Waldenstrom's Macroglobulinemia. 2491 31