Two concurrent phase II trials of paclitaxel/carboplatin/trastuzumab (weekly or every-3-week schedule) as first-line therapy in women with HER2-overexpressing metastatic breast cancer: NCCTG study 983252.

PURPOSE: The efficacy and tolerability of 2 different schedules of paclitaxel/carboplatin/trastuzumab for HER2-overexpressing metastatic breast cancer (MBC) were evaluated in this parallel multicenter phase II trial. PATIENTS AND METHODS: Patients received every-3-week therapy (n = 43) consisting of a 200 mg/m(2) dose of paclitaxel/carboplatin area under the curve (AUC) of 6 mg/mL per minute and trastuzumab (an initial 8 mg/kg dose and subsequent 6 mg/kg doses) administered every 21 days for 8 cycles or weekly therapy (n = 48) consisting of an 80-mg/m(2) dose of paclitaxel/carboplatin AUC of 2 mg/mL per minute for 3 of 4 weeks, with weekly trastuzumab (an initial 4-mg/kg dose and subsequent 2-mg/kg doses) administered every 4 weeks for 6 cycles. Trastuzumab was continued until disease progression or unacceptable toxicity. HER2 status was confirmed by a central laboratory review. RESULTS: The overall response rate (ORR) with every-3-week therapy was 65% (90% confidence interval [CI], 51%-77%), with a median time to disease progression of 9.9 months and median overall survival (OS) time of 2.3 years. The ORR with weekly therapy was 81% (90% CI, 70%-90%), with a median time to disease progression of 13.8 months and a median OS time of 3.2 years. Hematologic and nonhematologic toxicities occurred significantly less frequently with weekly therapy versus every-3-week therapy: grade 3/4 neutropenia (52% vs. 88%); grade 3 thrombocytopenia (4% vs. 30%); and grade 3 neurosensory toxicity (2% vs. 19%), respectively. CONCLUSIONS: Every-3-week and weekly regimens of paclitaxel/carboplatin/trastuzumab are highly active in women with HER2-overexpressing MBC. However, fewer patients developed severe neutropenia, leukopenia, or thrombocytopenia with the weekly schedule.

Cellular proteins bind to sequence motifs in the R1 element between the HCMV immune evasion genes.

The viral US3 and US6 gene products of human cytomegalovirus (CMV) are sequentially expressed at immediate-early and early times after infection, respectively. They downregulate the surface expression of HLA class I molecules. There are two repeat-containing regulatory regions between the US3 promoter and the US6 transcription unit designated R1 and R2. R2 contains repetitions of the NF-kappa B responsive element and enhances the immediate-early expression of the US3 gene. R1 contains 19 repetitions of a 5'-TRTCG-3' pentanucleotide arranged as everted repeats, inverted repeats, and variably spaced single pentanucleotides. In the context of the viral genome, R1 also enhances immediate-early US3 gene expression by an unknown mechanism (G. C. Bullock, et al., 2001, Virology 288, 164-174). We report a sequence motif within the R1 element that binds a human cell nuclear protein which is antigenically related to the Drosophila boundary element-associated factor (BEAF). The potential role of a 35-kDa cellular protein that binds to sequence motifs within the R1 element in regulating the expression of the CMV US3 immune evasion gene is discussed.