5-aminoimidazol-4-karboksiamid-1-β-d-ribofuranozid potiče nakupljanje leukemijskih stanica u S-fazi

master's thesis

• Title (english): 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside induces accumulation of leukemia cells in S-phase
• Author: Ivan Prepolec
• Mentor: Dora Višnjić (mentor)
• Committee member: Drago Batinić (predsjednik povjerenstva)
• Committee member: Zdravko Petanjek (član povjerenstva)
• Committee member: Dora Višnjić (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; (Department of Physiology and Immunology); Zagreb
• Defense date and country: 2015-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Clinical Biochemistry

Abstract

Proteinska kinaza aktivirana AMP-om (AMPK) služi kao stanični energetski senzor koji koči mTOR (ciljna molekula rapamicina u sisavaca) i zaustavlja proliferaciju. Modulatori signalnog puta AMPK/mTOR ispituju se u liječenju leukemija iako je mehanizam njihovog djelovanja samo djelomice razjašnjen. U našem istraživanju ispitali smo aktivnost signalnog puta AMPK/mTOR u sinkroniziranim leukemijskim stanicama te učinak njegovih farmakoloških modulatora na prolazak kroz stanični ciklus. Stanice akutne promijelocitne leukemije NB4 sinkronizirali smo nokodazolom. Analiza količine fosforiliranog p70S6K-a metodom Western blot u stanicama nakon otpuštanja iz nokodazolskog bloka pokazala je da je aktivnost mTOR-a niska tijekom prijelaza iz metazafe u G1-fazu te da se povećava se tijekom G1-faze. Učinak modulatora na prolazak stanica kroz stanični ciklus odredili smo protočnom citometrijom stanica označenih propidijevim jodidom. 5-aminoimidazol-4-karboksiamid-1-β-D-ribofuranozid (AICAR), metformin, rapamicin i tvar C nisu utjecali na povratak stanica iz G2/M-faze u G1-fazu 3 sata nakon otpuštanja iz nokodazolskog bloka. Međutim, AICAR je značajno povećao udio stanica u S-fazi nakon 24 sata. Rezultati našeg istraživanja pokazuju da AICAR potiče nakupljanje leukemijskih stanica u S-fazi što upućuje da bi se AICAR možda mogao koristiti u kombinaciji s drugim lijekovima za liječenje leukemija.

Abstract (english)

The AMP-activated protein kinase (AMPK) is a low-energy checkpoint that inhibits mTOR (mammalian target of rapamycin) kinase and suppresses proliferation. Modulators of AMPK/mTOR have been proposed in the treatment of leukemia, but the mechanism of their action is only partially understood. In this study, we investigated the activity of AMPK/mTOR pathway in synchronized leukemia cells and the effects of pharmacological modulators on cell cycle progression. Acute promyelocytic leukemia NB4 cells were synchronized with nocodazole. Western blot analysis of the levels of Thr389-phosphorylated p70S6K in cells released from block revealed that the activity of mTOR was low during M/G1 transition and increased as the cells progressed through G1-phase. The effect of AMPK/mTOR modulators on cell cycle progression was measured using flow cytometric analysis of propidium iodide-labelled cells. The presence of 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR), metformin, rapamycin or compound C had no significant effects on return of cells to G1-phase at 3 h after release. At 24 h after release, a significant increase in the percentage of S-phase was observed in cells treated with AICAR. The results of our study demonstrate that AICAR induces the accumulation of leukemia cells in S-phase suggesting a possible role for AICAR in combination therapy of leukemia.

• Keywords: NB4; AICAR; stanični ciklus; AMPK; mTOR
• Keywords (english): NB4; AICAR; cell cycle; AMPK; mTOR
• Language: croatian
• URN:NBN: urn:nbn:hr:105:674975
• Study programme: Title: Medicine; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: doktor/doktorica medicine (doktor/doktorica medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2016-04-08 12:13:01