Protein arginine (N)-methyl transferase 7 (PRMT7) as a potential target for the sensitization of tumor cells to camptothecins.

PRMT7 belongs to the protein arginine methyl-transferases family. We show that downregulation of PRMT7alpha and beta isoforms in DC-3F hamster cells was associated with increased sensitivity to the Top1 inhibitor camptothecin (CPT). This effect was not due to a change in Top1 contents or catalytic activity, or to a difference in the reversal of DNA breaks.

Neutralizing activity and antibody reactivity toward immunogenic regions of the human T cell leukemia virus type I surface glycoprotein in sera of infected patients with different clinical states.

The induction of specific neutralizing antibodies is an important part of vaccine strategy against human T cell leukemia virus type I (HTLV-I). A recently developed reporter gene induction assay was used to detect and quantify neutralizing antibodies in sera of HTLV-I-infected patients with different clinical states: Most sera (73/89) displayed an inhibitory activity. Neutralizing antibodies were more frequently detected in sera of patients with tropical spastic paraparesis/HTLV-associated myelopathy (TSP/HAM) or sicca syndrome (SS) (100%) than in sera of patients with adult T cell leukemia (ATL; 50%) or of asymptomatic carriers (AS; 83%).

Effects of bolesatine on a cell line from the SP2/O thymic lymphosarcoma.

Bolesatine, a toxic protein isolated from Boletus satanas Lenz inhibits in vitro protein synthesis in a concentration-dependent manner in a cell line from a radiation-induced thymic lymphosarcoma (SP2/O) with a 50% inhibitory concentration (IC50) of 9.5 nM (0.6 microgram/ml).

Identification of HTLV-I- or HTLV-II-producing cells by cocultivation with BHK-21 cells stably transfected with a LTR-lacZ gene construct.

The Syrian Hamster kidney cell line (BHK-21) was stably transfected with a plasmid vector containing the lacZ bacterial gene under the control of a HTLV-I-LTR promoter. In these cells termed pA18G-BHK-21, this lacZ construct is inducible by the tax protein produced by a tax expression vector. It was also shown that beta-galactosidase synthesis was detected within 48 h after cocultivation of pA18G-BHK-21 cells with HTLV-I (HUT-102, MT2, C91/PL, 2060) or HTLV-II (MoT strain) -producing cells.