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Background The presence of disseminated tumor cells (DTCs) in bone marrow of patients with early breast cancer (EBC) has been correlated with increased risk of metastatic disease or locoregional relapse. Zoledronic acid (ZOL) treatment has reduced DTCs in the bone marrow of patients with EBC in several studies. This controlled study sought to confirm these observations. Patients and methods Patients with EBC and DTC-positive bone marrow were randomized (N = 96) to treatment with ZOL plus adjuvant systemic therapy or adjuvant systemic therapy alone. The change in DTC numbers at 12 months versus baseline was measured. Results DTC-positive patients treated with ZOL were more likely to become DTC-negative after 12 months of treatment compared with the controls (67% versus 35%; P = 0.009). At 12 months, DTC counts decreased to a mean of 0.5 ± 0.8 DTCs in the ZOL group and to 0.9 ± 0.8 DTCs in the control group. In addition, ZOL was generally well tolerated. Conclusions Treatment with ZOL improves elimination of DTCs. Further studies are needed to determine whether the reduction in DTCs by ZOL provides clinical benefit. [ABSTRACT FROM PUBLISHER]

Summary The function of the LysR-type regulator LrhA of Escherichia coli was defined by comparing whole-genome mRNA profiles from wild-type E. coli and an isogenic lrhA mutant on a DNA microarray. In the lrhA mutant, a large number (48) of genes involved in flagellation, motility and chemotaxis showed relative mRNA abundances increased by factors between 3 and 80. When a representative set of five flagellar, motility and chemotaxis genes was tested in lacZ reporter gene fusions, similar factors for derepression were found in the lrhA mutant. In gel retardation experiments, the LrhA protein bound specifically to flhD and lrhA promoter DNA (apparent KD ≈ 20 nM), whereas the promoters of fliC , fliA and trg were not bound by LrhA. The expression of flhDC (encoding FlhD2 C2 ) was derepressed by a factor of 3.5 in the lrhA mutant. FlhD2 C2 is known as the master regulator for the expression of flagellar and chemotaxis genes. By DNase I footprinting, LrhA binding sites at the flhDC and lrhA promoters were identified. The lrhA gene was under positive autoregulation by LrhA as shown by gel retardation and lrhA expression studies. It is suggested that LrhA is a key regulator controlling the transcription of flagellar, motility and chemotaxis genes by regulating the synthesis and concentration of FlhD2 C2 . [ABSTRACT FROM AUTHOR]