Can image analysis provide evidence that lysosomal sequestration mediates daunorubicin resistance?

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15110%2F20%3A73604840" target="_blank" >RIV/61989592:15110/20:73604840 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0009279720304890?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0009279720304890?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.cbi.2020.109138" target="_blank" >10.1016/j.cbi.2020.109138</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Can image analysis provide evidence that lysosomal sequestration mediates daunorubicin resistance?

Popis výsledku v původním jazyce

Altered intracellular distribution of weak base anticancer drugs owing to lysosomal sequestration is one purported mechanism contributing to chemotherapy resistance. This has often been demonstrated with the example of daunorubicin (DNR), chemotherapy with its characteristic red fluorescence used to trace it in cellular compartments. Here we addressed the question whether image analysis of DNR fluorescence can reflect its real intracellular distribution. We observed that the relationship between the intensity of the DNR fluorescence and its concentration in water solutions with or without proteins is far from linear. In contrast, nucleic acids, RNA and DNA in particular, dramatically diminish the DNR fluorescence, however, the intensity was proportional to the amount. Therefore, image analysis reflects the composition of different cell compartments (i.e., the presence of proteins and nucleic acids) rather than the actual concentration of DNR in these compartments. In line with these results, we observed highly fluorescent lysosomes and low fluorescent nucleus in sensitive cancer cells treated with low DNR concentrations, a fluorescence pattern thought to be found only in resistant cancer cells. Importantly, LC/MS/MS analysis of extracts from sensitive cells treated with DNR or DNR in combination with an inhibitor of vacuolar ATPase, concanamycin A, indicated that lysosomal accumulation of DNR increased with increasing extracellular concentration. However, even the highest lysosomal accumulation of DNR failed to reduce its extralysosomal concentration and thus change the cell sensitivity to the drug. In conclusion, our results strongly suggest that DNR fluorescence within cells does not indicate the real drug distribution. Further they suggested that lysosomal sequestration of DNR can hardly contribute to its resistance in cancer cells in vitro.

Název v anglickém jazyce

Can image analysis provide evidence that lysosomal sequestration mediates daunorubicin resistance?

Popis výsledku anglicky

Altered intracellular distribution of weak base anticancer drugs owing to lysosomal sequestration is one purported mechanism contributing to chemotherapy resistance. This has often been demonstrated with the example of daunorubicin (DNR), chemotherapy with its characteristic red fluorescence used to trace it in cellular compartments. Here we addressed the question whether image analysis of DNR fluorescence can reflect its real intracellular distribution. We observed that the relationship between the intensity of the DNR fluorescence and its concentration in water solutions with or without proteins is far from linear. In contrast, nucleic acids, RNA and DNA in particular, dramatically diminish the DNR fluorescence, however, the intensity was proportional to the amount. Therefore, image analysis reflects the composition of different cell compartments (i.e., the presence of proteins and nucleic acids) rather than the actual concentration of DNR in these compartments. In line with these results, we observed highly fluorescent lysosomes and low fluorescent nucleus in sensitive cancer cells treated with low DNR concentrations, a fluorescence pattern thought to be found only in resistant cancer cells. Importantly, LC/MS/MS analysis of extracts from sensitive cells treated with DNR or DNR in combination with an inhibitor of vacuolar ATPase, concanamycin A, indicated that lysosomal accumulation of DNR increased with increasing extracellular concentration. However, even the highest lysosomal accumulation of DNR failed to reduce its extralysosomal concentration and thus change the cell sensitivity to the drug. In conclusion, our results strongly suggest that DNR fluorescence within cells does not indicate the real drug distribution. Further they suggested that lysosomal sequestration of DNR can hardly contribute to its resistance in cancer cells in vitro.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10608 - Biochemistry and molecular biology

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

CHEMICO-BIOLOGICAL INTERACTIONS

ISSN

0009-2797

e-ISSN

—

Svazek periodika

2020

Číslo periodika v rámci svazku

327

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

8

Strana od-do

2-9

Kód UT WoS článku

000558608300012

EID výsledku v databázi Scopus

—