Phase 2 Study of Iodine-131 Tositumomab Plus Chemotherapy in Patients With Previously Untreated Mantle-Cell Lymphoma.

Background: Mantle-cell lymphoma (MCL) is sensitive to radiotherapy, and the CD20 antigen is relatively highly expressed in MCL. Therefore, radioimmunotherapy using radiolabeled anti-CD20 monoclonal antibodies has the potential to treat MCL. The objective of this study was to investigate the efficacy, pharmacokinetics, and safety of tositumomab (TST) and iodine-131 tositumomab (I-131 TST) followed by 6 cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in patients with previously untreated MCL (ClinicalTrials.

CHOP Chemotherapy Followed by Tositumomab and Iodine-131 Tositumomab for Previously Untreated Diffuse Large B-cell Lymphoma.

The efficacy and safety of tositumomab/iodine-131 tositumomab (TST/I-131 TST) were evaluated in diffuse large B-cell lymphoma patients who responded to first-line cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). Fifteen patients (median age, 52 years) received dosimetric and therapeutic doses of TST/I-131 TST. The most common Grade 3/4 hematologic adverse events were decreased absolute neutrophil count (47%), white blood cell count (40%), platelet count (27%), and hemoglobin (20%).

Observational Retrospective Study of Altered Biodistribution of Tositumomab and 131I-Tositumomab.

Unlabelled: The tositumomab/(131)I-tositumomab radioimmunotherapy regimen is administered as a dosimetric dose followed by a therapeutic dose. The biodistribution of the dosimetric dose is assessed by quantitative calculations of whole-body residence time (TBRT) and visual examination of whole-body γ-camera images, to determine the administered radioactivity dose and whether a therapeutic dose can be administered. We investigated whether altered biodistribution of (131)I-tositumomab could be identified using quantitative TBRT.

Stimulation of polo-like kinase 3 mRNA decay by tristetraprolin.

Polo-like protein kinase 3 (Plk3) has been proposed to regulate entry into S phase and promote apoptosis in response to oxidative stress. Its mRNA contains three AU-rich elements (AREs) in its 3' untranslated region (3'-UTR) that can contribute to the rapid degradation of labile transcripts. We investigated the possibility that tristetraprolin (TTP), a tandem CCCH zinc finger protein, could promote the decay of Plk3 transcripts.

Phosphorylation of GRK1 and GRK7 by cAMP-dependent protein kinase attenuates their enzymatic activities.

Phosphorylation of G protein-coupled receptors is a critical step in the rapid termination of G protein signaling. In rod cells of the vertebrate retina, phosphorylation of rhodopsin is mediated by GRK1. In cone cells, either GRK1, GRK7, or both, depending on the species, are speculated to initiate signal termination by phosphorylating the cone opsins.