Human c-Myb proto-oncogene is highly expressed in hematopoietic progenitors as well as leukemia and certain solid tumor. However, the regulatory mechanisms of its expression and biological functions remain largely unclear. Recently, c-Myb has been shown to be targeted by microRNA-150 (miR-150) which thereby controls B cell differentiation in mice. In this study, we demonstrated that c-Myb is an...

MYB oncogene upregulation is associated with estrogen receptor (ER)-positive breast cancer, but disease requirements for MYB function in vivo have not been explored. In this study, we provide evidence of a critical requirement forMYB functions inmodels of human andmurine breast cancer. In human breast cancer, we found thatMYB expression was critical for tumor cell growth both in vitro and in vi...

We report that the c-myb protein binds to another site, MBS-II, in the SV40 enhancer with low affinity. In co-transfection experiments with a c-myb expression plasmid, tandem repeats of the sequence containing the MBS-II site induced c-myb-dependent transcriptional repression. Results of mutational analyses of the sequence around the MBS-II site suggested that the c-myb protein represses transc...

Cyclin A1 differs from other cyclins in its highly restricted expression pattern. Besides its expression during spermatogenesis, cyclin A1 is also expressed in hematopoietic progenitor cells and in acute myeloid leukemia. We investigated mechanisms that might contribute to cyclin A1 expression in hematopoietic cells. Comparison of cyclin A1 and cyclin A promoter activity in adherent and myeloid...

BACKGROUND MYB is predicted to be a favorable prognostic predictor in a breast cancer population. We proposed to find the inferred mechanism(s) relevant to the prognostic features of MYB via a supervised network analysis. METHODS Both coefficient of intrinsic dependence (CID) and Galton Pierson's correlation coefficient (GPCC) were combined and designated as CIDUGPCC. It is for the univariate...

The murine neutrophil elastase (NE) gene is expressed specifically in immature myeloid cells. A 91-bp NE promoter region contains three cis elements which are conserved evolutionarily and are essential for activation of the promoter in differentiating 32D cl3 myeloid cells. These elements bound c-Myb (at -49), C/EBPalpha (at -57), and PU.1 (at -82). In NIH 3T3 cells, the NE promoter was activat...

Our previous studies showed that MYB is required for proliferation of, and confers protection against apoptosis on, estrogen receptor-positive (ER(+ve)) breast cancer cells, which are almost invariably also MYB(+ve). We have also shown that MYB expression in ER(+ve) breast cancer cells is regulated at the level of transcriptional elongation and as such, is suppressed by CDK9i. Here we examined ...

A pivotal role has been assigned to Myb in the control of myeloid cell growth. Although Myb is a target of retinoic acid, little is known about the mechanisms by which it may contribute to induced growth arrest in leukemia cells. Indeed, few Myb target genes are known to be linked to proliferation. Myeloblastin is involved in the control of proliferation in myeloid leukemia cells. It is express...

The A-Myb transcription factor is structurally related to the c-myb proto-oncogene and is involved in the control of proliferation and/or differentiation of mature B lymphocytes. We have shown previously by PCR analysis that A-myb is preferentially expressed in CD38+ CD39- sIgM- mature B cells. We demonstrate here, using in situ hybridization, that A-myb expression is restricted to the dark zon...

Objective: Recent studies revealed the existence of ectopic gene at t(6;9)(q22-23;p23-24) in adenoid cystic carcinoma (ACC), resulting in MYB-NFIB fusion gene formation. In this study, we discuss the expression of MYB of ACC in salivary gland and its clinicopathological significance. Methods: We examined 98 samples of salivary gland adenoid cystic carcinoma and 68 samples of salivary non-ACC ne...