Combined treatment in pediatric solid tumors of neurogenic origin using tyrosine kinase inhibitors and thiosemicarbazone iron chelators

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F65269705%3A_____%2F19%3A00070611" target="_blank" >RIV/65269705:_____/19:00070611 - isvavai.cz</a>

Result on the web

<a href="https://www.linkos.cz/files/klinicka-onkologie/451.pdf" target="_blank" >https://www.linkos.cz/files/klinicka-onkologie/451.pdf</a>

DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Combined treatment in pediatric solid tumors of neurogenic origin using tyrosine kinase inhibitors and thiosemicarbazone iron chelators

Original language description

Introduction: Multi-drug resistance (MDR) presents an obstacle in treating pediatric solid tumors like medulloblastoma or neuroblastoma. Mechanisms often responsible for MDR are up-regulation of ATP-binding cassette (ABC) transporters expressed either on plasma or lysosomal membranes, and sequestration of drugs into lysosomes where the drugs are inactivated due to acidic pH. Such mechanism was also described for tyrosine kinase inhibitors (TKIs). However, combining TKIs with novel thiosemicarbazone iron chelators could present a way of overcoming MDR. Thiosemicarbazones target iron metabolism in cancer cells and a number of signaling pathways. They are transported into lysosomes where they bind iron or copper ions and create reactive oxygen species that permeate the lysosomal membrane, so the drugs previously trapped in lysosomes are released and are no longer separated from their targets. Material and Methods: Established cell lines DAOY (medulloblastoma), SH-SY5Y and SK-N-BE(2) (neuroblastoma) were used in this study. Lysosomotropic TKIs gefitinib, lapatinib and sunitinib, combined with thiosemicarbazones - Dp44mT and DpC were used in this study. We analyzed phosphorylation of receptor tyrosine kinases (RTKs) using Human Phospho-RTK Array (R&amp;D Systems) and expression of selected ABC transporters by Western blot and qRT-PCR. Viability of cells was measured by MTT test and the effect of combining selected drugs was analyzed using Chou Talalay method in CalcuSyn software (Biosoft). Results: Although we found phosphorylated targets of used TKIs - EGFR in all cell lines and PDGFRβ in neuroblastoma cell lines - the effect of combining TKIs with thiosemicarbazones was synergistic only in DAOY cell line. In both neuroblastoma cell lines, we observed antagonistic effects with the exception of gefitinib. Combining gefitinib that targets phosphorylated EGFR with thiosemicarbazones showed additive effects. Therefore, we postulate that observed difference could be caused by different phosphorylation of RTKs and expression of ABC transporters. High levels of ABCB1 and ABCG2 were found in SH-SY5Y and DAOY cell lines, respectively. Conclusion: Our study shows that combining TKIs and novel thiosemicarbazones in DAOY cell line resulted in synergistic effects and could present an effective means of overcoming MDR. On the contrary, in both neuroblastoma cell lines, the drugs were effective when used alone, but their combined synergistic effects were not found.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

30204 - Oncology

Project

<a href="/en/project/NV16-34083A" target="_blank" >NV16-34083A: Receptor tyrosin kinases and downstream signaling pathways as possible therapeutic targets in pediatric refractory solid tumors</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2019

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů