Phorbol 12,13-dibutyrate

Phorbol 12,13-dibutyrate, a phorbol ester, is an activator of PKC, including the conventional calcium-dependent subtypes (α and γ), the nonconventional calcium-independent isoforms (δ, ε, η), as well as the atypical calcium-independent and DAG or phorbol ester-unresponsive subtype (ζ). PKC plays an important role in the regulation of a variety of cellular processes such as exocytosis, gene expression, cell proliferation and differentiation, as well as tumor promotion, thereby representing the major target for tumor-promoting phorbol esters and chemically unrelated tumor promoters. Phorbol esters are able to replace the endogenous activator DAG in the stimulation of PKC, and participate in the multistage process of tumor formation and progression.

References:

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