Kinase assays

Protein kinase C was assayed by measuring the incorporation of 32P into H1 histone from [γ-32P]ATP. The standard reaction mixture (0.25 ml) contained 5 pmol of Tris/HCl at pH 7.5, 1.25 pmol of magnesium nitrate, 50 pg of H1 histone, 2.5 nmol of [γ-32P]ATP (5 to 15xl04 cpm/nmol), and 0.5 pg of protein kinase C. Phospholipid, diolein, phorbol esters, and Ca2+ were added as indicated in each experiment. All reagents were taken up in water which was prepared by a double distillation apparatus followed by passing through a Chelex 100 column to remove as much Ca2+ as possible. After incubation for 3 min at 30oC, the reaction was stopped by the addition of 25% trichloroacetic acid, and acid-precipitable materials were collected on a Toyo-Roshi membrane filter (pore size, 0.45 pm). The catalytic fragment of protein kinase C was assayed similarly except that Ca2+, phospholipid, and diolein were omitted.

Cell lines

B-lymphocyte cell line

Preparation method

The solubility of this compound in DMSO is >10 mM. General tips for obtaining a higher concentration: Please warm the tube at 37℃ for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below -20℃ for several months.

Reacting condition

1 nM

Applications

12-O-tetradecanoyl phorbol-13-acetate was used for the activation of PKC (protein kinase C) in cells.

Animal models

Chemical skin carcinogenesis mice

Dosage form

Twice weekly treatment (12.5 μg in 100 μL acetone)

Application

12-O-tetradecanoyl phorbol-13-acetate was used to induce skin cancer in mice.

Other notes

Please test the solubility of all compounds indoor, and the actual solubility may slightly differ with the theoretical value. This is caused by an experimental system error and it is normal.

• Biomed Pharmacother 151 (2022): 113175. PMID:35623172
• Int immunopharmacol 113 (2022): 109474. PMID:36417823

12-O-tetradecanoyl phorbol-13-acetate (TPA) is an activator of ERK/MAPK with the concentration of 50μm [1].

ERK is an extracellular signal-regulated kinase and transfers signals from a receptor on the cell surface to DNA cooperated with MAPK. It is reported that ERK deficiency leads to the cell uncontrolled growth and is regarded as a target to cure cancers.

TPA is a potent ERK activator. When tested with A549 cells (human lung cancer cell line), TPA treatment led to an early, strong, and relatively transient ERK phosphorylation [2]. In mouse embryo fibroblasts from DUSP5 (+/+) mice, administration of TPA increased levels of ERK expression [3].

In transgenic (Eisuke) mice expressing a F?rster resonance energy transfer (FRET) biosensor for ERK, ERK activity was gradually stimulated upon topical TPA treatment and reached the peak approximately 6 hr later [1].

It is also reported that TPA treatment increased the accumulation of immature myeloid cells and the formation of papillomas during epidermal carcinogenesis (important in the tumor formation) when tested with S100A9 transgenic mice [4].

References:
[1]. Hiratsuka, T., et al., Intercellular propagation of extracellular signal-regulated kinase activation revealed by in vivo imaging of mouse skin. Elife, 2014. 4.
[2]. Refsnes, M., et al., Differential NF-kappaB and MAPK activation underlies fluoride- and TPA-mediated CXCL8 (IL-8) induction in lung epithelial cells. J Inflamm Res, 2014. 7: p. 169-85.
[3]. Rushworth, L.K., et al., Dual-specificity phosphatase 5 regulates nuclear ERK activity and suppresses skin cancer by inhibiting mutant Harvey-Ras (HRasQ61L)-driven SerpinB2 expression. Proc Natl Acad Sci U S A, 2014. 111(51): p. 18267-72.
[4]. Ortiz, M.L., et al., Immature myeloid cells directly contribute to skin tumor development by recruiting IL-17-producing CD4+ T cells. J Exp Med, 2015.