At the gene level, CADM1 expression level upregulated caspase-3 activity and expression of Bax and p27 protein and downregulated levels of B cell lymphoma-2, cyclinD1, cyclinE1 and cyclin dependent kinase 2 proteins.
Moreover, we found that overexpression of miR-455-3p significantly elevated the protein levels of p27 kinase inhibition protein (KIP) 1, Bax, pro-caspase-3, and active caspase-3, and markedly downregulated the levels of B-cell lymphoma-2 (Bcl-2).
We evaluated Cdc25A mRNA expression by in situ hybridization and p27 protein expression by immunohistochemistry in 42 histologically indolent B-cell non-Hodgkin lymphoma (NHL and 51 histologically aggressive B-cell NHL.
High grade lymphomas showed markedly decreased p21 expression (3.9 in Hg-NHL vs. 12 in Lg-NHL and 29 in CLL; values expressed as mRNA transcripts x 10(3), p < 0.009). mRNA and protein expression of p27 was considerably higher in CLL than in the lymphomas.
We analyzed the causes of this anomalous presence of p27 in a group of aggressive B-cell lymphomas, including 54 cases of diffuse large B-cell lymphomas and 20 Burkitt's lymphomas.