Intracellular leucine-rich alpha-2-glycoprotein-1 competes with Apaf-1 for binding cytochrome c in protecting MCF-7 breast cancer cells from apoptosis.

Leucine-rich alpha-2-glycoprotein-1 (LRG1) has been shown to compete with apoptosis activating factor-1 (Apaf-1) for binding cytochrome c (Cyt c) and could play a role in inhibition of apoptosis. Employing MCF-7 breast cancer cells, we report that intracellular LRG1 does protect against apoptosis. Thus, cells transfected with the lrg1 gene and expressing higher levels of LRG1 were more resistant to hydrogen peroxide-induced apoptosis than parental cells, while cells in which LRG mRNA was knocked down by short hairpin (sh) RNA-induced degradation were more sensitive.

Persistent HIV-1 replication is associated with lower antiretroviral drug concentrations in lymphatic tissues.

Antiretroviral therapy can reduce HIV-1 to undetectable levels in peripheral blood, but the effectiveness of treatment in suppressing replication in lymphoid tissue reservoirs has not been determined. Here we show in lymph node samples obtained before and during 6 mo of treatment that the tissue concentrations of five of the most frequently used antiretroviral drugs are much lower than in peripheral blood. These lower concentrations correlated with continued virus replication measured by the slower decay or increases in the follicular dendritic cell network pool of virions and with detection of viral RNA in productively infected cells.

Persistence of Kaposi sarcoma-associated herpesvirus (KSHV)-infected cells in KSHV/HIV-1-coinfected subjects without KSHV-associated diseases.

Inguinal lymph nodes from 24 human immunodeficiency virus (HIV) type 1-infected subjects without Kaposi sarcoma-associated herpesvirus (KSHV)-associated diseases were examined for KSHV infection. KSHV-infected cells were detected at a very low frequency in the lymph nodes of 7 subjects (median frequency, 2 infected cells/10(7) lymph node cells). Latent, but not lytic, KSHV gene expression was detected and KSHV-infected cells were located in B cell-rich areas of lymph node follicles.

Lymphatic dysfunction in transgenic mice expressing KSHV k-cyclin under the control of the VEGFR-3 promoter.

Kaposi sarcoma-associated herpesvirus (KSHV) infects endothelial cells within KS tumors, and these cells express the KSHV latent-cycle gene k-cyclin (kCYC) as well as vascular endothelial growth factor receptor 3 (VEGFR-3), a marker for lymphatic endothelium. To further understand KSHV-mediated pathogenesis, we generated transgenic mice expressing kCYC under the control of the VEGFR-3 promoter. kCYC mRNA and functional protein expression within tissue correlated with VEGFR-3 expression and were most abundantly detected within lung tissue.

A pilot study of cidofovir in patients with kaposi sarcoma.

A clinical trial was conducted to test the activity of cidofovir (CDV), a drug with in vitro activity against Kaposi sarcoma (KS)-associated herpesvirus (KSHV), in KS. Five patients with human immunodeficiency virus-associated KS (4 receiving antiretroviral therapy) and 2 patients with classical KS were administered CDV (5 mg/kg/dose) weekly for 2 weeks and then every other week. All 7 patients had progression of their KS at a median of 8.