Vpliv metformina na rakave celice v kulturi v odvisnosti od razpoložljivih hranil

Bizjak, Maruša (author), Pavlin, Mojca (mentor), Pirkmajer, Sergej (comentor)

Metformin se uporablja za zdravljenje sladkorne bolezni in nedavne raziskave so nakazale, da ima morda protirakave učinke. Cilj doktorske disertacije je bil proučiti delovanje metformina na rakave celice v odvisnosti od razpoložljivih hranil v gojišču. Pri tem smo primerjali učinke metformina na klasični enoslojni kulturi z učinki na tumorskih sferoidih. Z uporabo različnih metod za določanje števila, proliferacije, živosti celic in deleža mrtvih celic smo določili, da pomanjkanje piruvata, neesencialnih aminokislin in glukoze poveča učinek metformina na celice MDA-MB-231. Pri pomanjkanju piruvata in/ali glukoze je pri celicah MDA-MB-231 izpostavljenih metforminu nastopila energijska kriza, ki je spodbudila aktivacijo AMPK, kar smo določili s prenosom western. Z uporabo različnih protokolov menjave gojišča in meritvami porabe glukoze smo pojasnili nasprotujoče si rezultate nekaterih raziskav, ki so proučevale učinek nižjih koncentracij glukoze (5–5,6 mM) na delovanje metformina na celice MDA-MB-231. Poleg tega smo povečali učinek metformina na celice MDA-MB-231, MCF-7 in PC-3 z uporabo inhibitorja glikolize, 2-deoksi-D-glukoze (2-DG). Nepričakovano smo opazili, da kombinacija 2-DG in metformina pri 5,6 mM glukozi poveča delež živih odluščenih celic MDA-MB-231 in MCF-7, kar bi bilo lahko pomembno pri razumevanju vpliva presnovnih sprememb na proces metastaziranja rakavih celic.

• Language: Slovenian
• Keywords: metabolizem rakavih celic, metformin, 2-deoksi-D-glukoza, AMPK, celice raka dojke, koncentracija hranil, luščenje živih celic
• Work type: Doctoral dissertation
• Organization: BF - Biotechnical Faculty
• Year: 2018
• PID: 20.500.12556/RUL-105207
• COBISS.SI-ID: 928887
• Publication date in RUL: 10.11.2018

BIZJAK, Maruša, 2018, Vpliv metformina na rakave celice v kulturi v odvisnosti od razpoložljivih hranil [online]. Doctoral dissertation. [Accessed 11 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=105207

Secondary language

• Language: English
• Title: Effects of metformin on cancer cells in vitro as a function of the available nutrients

Abstract

Here we show that depletion of pyruvate, non-essential amino acid and glucose increases the effects of metformin on MDA-MB-231 cells. The effects of metformin differ also between monolayer culture and tumour spheroids. Our results indicate that in glucose-depleted media metformin supressed MDA-MB-231 cell proliferation and reduced their survival due to inhibition of oxidative phosphorylation. In the absence of glucose, MDA-MB-231 cells were unable to adapt to energy crises induced by metformin via upregulation of glycolysis. Thus, metformin probably supressed cellular proliferation in an AMPK-independent manner. Since the absence of glucose increases the effects of metformin on MDA-MB-231 cells, metformin could target cancer cells in a poorly perfused core of the tumour. Medium renewal blocked the anti-proliferative effects of metformin in the presence of 5,6 mM of glucose, which might explain inconsistent results in previous studies. Metformin reduces the number of MDA-MB-231 cells synergistically with 2-DG, which is a competitive inhibitor of glycolysis. Finally, we have observed that combined treatment with metformin and 2-DG induces detachment of viable MDA-MB-231 and MCF-7 cells from the bottom of cell culture wells, which might be important to better understand the effects of changes in metabolic pathways on the process of cancer cell metastazation.

• Keywords: cancer cell metabolism, metformin, 2-deoxy-D-glucose, AMP-activated protein kinase, breast cancer cells, nutrient concentrations, detachment of viable cells