Expression of G1-Phase Cell Cycle Genes during Hematopoietic Lineage

Roles for c-Myc in Self-renewal of Hematopoietic Stem Cells

“…However, neither Notch 1 nor HOXB4 up-regulated the expression of cyclin D1, whereas its expression was up-regulated by these molecules in other cell types (as described above). These findings were consistent with the previous report that cyclin D1 was not detected in the proliferating normal hematopoietic stem/progenitor cells (50). Although cyclin D1 expression did not accompany the proliferation of normal hematopoietic stem/progenitor cells, our results suggest that G 1 /S transition in self-renewal of HSCs is not so unique but rather common to other cell types.…”

CDK6 blocks differentiation: coupling cell proliferation to the block to differentiation in leukemic cells

“…There is circumstantial evidence linking CDK6 to leukemia and other cancers. Compared with CDK4, CDK6 is preferentially expressed in all hematopoietic cell types and exclusively expressed in some hematopoietic cells (Meyerson and Harlow, 1994;Della Ragione et al, 1997). Translocations involving human chromosome 7q are the most common cytogenetic abnormalities in splenic lymphoma with villous lymphocytes, a leukemic variant of splenic marginal zone lymphoma, and in several patients the translocation breakpoints have been found to lie in the CDK6 promoter region (Corcoran et al, 1999).…”

Cell cycle regulators and hematopoiesis

“…In a myeloblast model, IL-3 was shown to support progression through mid-G1 phase by inducing expression of cdk4, cyclin D2 and cyclin D3 (Ando et al, 1993;Ando and Gri n, 1995). Several investigators have surveyed steady-state levels of cell cycle regulators in various hematopoietic subsets (Della Ragione et al, 1997;Furukawa et al, 2000;Taniguchi et al, 1999). Della Ragione detected high levels of cdk6, cyclins D2 and D3 and of the cdki p15 in all progenitors.…”