Differential expression of protein kinase C isoenzymes related to high nitric oxide synthase activity in a T lymphoma cell line.

GORELIK G, BARREIRO ARCOS ML, KLECHA AJ, CREMASCHI GA.

BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR BASIS OF DISEASE

Elsevier Science b.v.

Lugar: Amsterdam, Holanda; Año: 2002 vol. 1588 p. 179 - 188

0925-4439

Protein kinase C (PKC) is critical for T lymphocyte activation and proliferation, while nitric oxide synthase (NOS) may function both as an activator or inhibitor of T cell apoptosis. Both enzymatic activities were studied in T lymphoma cells in comparison to normal and activated T lymphocytes. Here we show a higher translocation of PKC in BW5147 lymphoma cells than in mitogen-stimulated T lymphocytes. Tumor cells overexpressed PKC æ isoform, while high levels of the PKC â isotype were found in mitogen-stimulated T lymphocytes. Moreover, tumoral T cells showed high NOS activity, almost undetectable in normal or stimulated T lymphocytes. PKC and NOS inhibitors or the intracellular delivery of an anti-PKC æ antibody diminished both NO production and proliferation in tumor cells. These results suggest that atypical PKC æ isoform expression and its association with NOS activity regulation would participate in the multistep process leading to BW5147 cell malignant transformation.