• Home
  • Search Results
  • Selective inhibition of RET mediated cell proliferation in vitro by the kinase inhibitor SPP86.

Selective inhibition of RET mediated cell proliferation in vitro by the kinase inhibitor SPP86.

BMC cancer (2014-11-21)
John P Alao, Sona Michlikova, Peter Dinér, Morten Grøtli, Per Sunnerhagen
ABSTRACT

The RET tyrosine kinase receptor has emerged as a target in thyroid and endocrine resistant breast cancer. We previously reported the synthesis of kinase inhibitors with potent activity against RET. Herein, we have further investigated the effect of the lead compound SPP86 on RET mediated signaling and proliferation. Based on these observations, we hypothesized that SPP86 may be useful for studying the cellular activity of RET. We compared the effects of SPP86 on RET-induced signaling and proliferation in thyroid cancer cell lines expressing RET-PTC1 (TPC1), or the activating mutations BRAFV600E (8505C) and RASG13R (C643). The effect of SPP86 on RET- induced phosphatidylinositide 3-kinases (PI3K)/Akt and MAPK pathway signaling and cell proliferation in MCF7 breast cancer cells was also investigated. SPP86 inhibited MAPK signaling and proliferation in RET/PTC1 expressing TPC1 but not 8505C or C643 cells. In TPC1 cells, the inhibition of RET phosphorylation required co-exposure to SPP86 and the focal adhesion kinase (FAK) inhibitor PF573228. In MCF7 cells, SPP86 inhibited RET- induced phosphatidylinositide 3-kinases (PI3K)/Akt and MAPK signaling and estrogen receptorα (ERα) phosphorylation, and inhibited proliferation to a similar degree as tamoxifen. Interestingly, SPP86 and PF573228 inhibited RET/PTC1 and GDNF- RET induced activation of Akt and MAPK signaling to a similar degree. SPP86 selectively inhibits RET downstream signaling in RET/PTC1 but not BRAFV600E or RASG13R expressing cells, indicating that downstream kinases were not affected. SPP86 also inhibited RET signaling in MCF7 breast cancer cells. Additionally, RET- FAK crosstalk may play a key role in facilitating PTC1/RET and GDNF- RET induced activation of Akt and MAPK signaling in TPC1 and MCF7 cells.

MATERIALS
Product Number
Brand
Product Description

USP
Dehydrated Alcohol, United States Pharmacopeia (USP) Reference Standard
Supelco
Dehydrated Alcohol, Pharmaceutical Secondary Standard; Certified Reference Material
USP
Glycerin, United States Pharmacopeia (USP) Reference Standard
Supelco
Ethanol standards 10% (v/v), 10 % (v/v) in H2O, analytical standard
Sigma-Aldrich
Ethanol Fixative 80% v/v, suitable for fixing solution (blood films)
Sigma-Aldrich
Glycerin, meets USP testing specifications
Supelco
4-tert-Octylphenol monoethoxylate solution, 10 μg/mL in acetone, analytical standard
Supelco
Glycerin, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
4-tert-Octylphenol monoethoxylate solution, 1 μg/mL in acetone, analytical standard
Supelco
Ethanol solution, certified reference material, 2000 μg/mL in methanol
Sigma-Aldrich
Glycerol solution, 83.5-89.5% (T)
Sigma-Aldrich
Glycerol solution, puriss. p.a., 86-89% (T)
Sigma-Aldrich
Glycerol solution, puriss., meets analytical specification of Ph. Eur., BP, 84-88%
Sigma-Aldrich
Dimethyl sulfoxide, sterile-filtered, BioPerformance Certified, meets EP, USP testing specifications, suitable for hybridoma
Sigma-Aldrich
Dimethyl sulfoxide, BioUltra, for molecular biology, ≥99.5% (GC)
Sigma-Aldrich
Glycerol, tested according to Ph. Eur., anhydrous
Supelco
Dimethyl sulfoxide, analytical standard
Sigma-Aldrich
Estradiol, meets USP testing specifications
Sigma-Aldrich
4-Hydroxytamoxifen, ≥70% Z isomer (remainder primarily E-isomer)
Sigma-Aldrich
Dimethyl sulfoxide, PCR Reagent
Sigma-Aldrich
Dimethyl sulfoxide, Hybri-Max, sterile-filtered, BioReagent, suitable for hybridoma, ≥99.7%
Sigma-Aldrich
Dimethyl sulfoxide, meets EP testing specifications, meets USP testing specifications
Sigma-Aldrich
Dimethyl sulfoxide, for molecular biology
Sigma-Aldrich
Glycerol, for molecular biology, ≥99.0%
Sigma-Aldrich
Dimethyl sulfoxide, ≥99.5% (GC), suitable for plant cell culture
Sigma-Aldrich
Glycerol, BioXtra, ≥99% (GC)
Sigma-Aldrich
Glycerol, ≥99.5%
Sigma-Aldrich
Glycerol, BioReagent, suitable for cell culture, suitable for insect cell culture, suitable for electrophoresis, ≥99% (GC)
Sigma-Aldrich
Tamoxifen, ≥99%
Sigma-Aldrich
DAPI, for nucleic acid staining