Antitumor efficacy of curcumin, bleomycin and hyperthermia on Ehrlich ascites tumor cells

Kemoterapija je jedan od najnaprednijih i najučinkovitijih pristupa u borbi protiv tumora. Primjenom kemoterapije sprječava se proliferacija i širenje tumorskih stanica, te potiče proces apoptoze. Kemoterapiju osim apoptoze često prati proces nekroze koja prouzrokuje oštećenje i okolnoga zdravoga tkiva. Budući da su flavonoidi u drugim istraživanjima već pokazali učinkovitost protiv tumorskih stanica i mogućnost smanjivanja razine oštećenja u zdravim stanicama, u ovom istraživanju proučavan je in vitro učinak kurkumina (1,7-bis(4-hidroksi-3-metoksifenil)hepta-1,6-dien-3,5-dion) na proliferaciju stanica Ehrlichovog ascitesnog tumora (EAT), te njegov utjecaj na pokretanje apoptoze/nekroze kod stanica Ehrlichovog ascitesnog tumora i njegov učinak u kombinaciji s bleomicinom i hipertermijom. Stanice EAT su rasle u Swiss albino miševima, iz kojih su izvađene nakon 7 dana, te su kultivirane u hranjivom mediju, obrađene kurkuminom, bleomicinom i hipertermijom. Antiproliferativni učinak test komponenti potvrđen je testom kolorimetrije (MTS testom) neposredno nakon kratkoročne inkubacije bleomicinom tijekom 2 h te kurkuminom slijedeća 2 h pri fiziološkim (37 C) ili hipertermalnim (43 C) uvjetima te nakon obrade stanica tijekom 24 sata. Analiziran je postotak tumorskih stanica u apoptozi i nekrozi na protočnom citometru te istražen genotoksični učinak komet testom. Kurkumin je pokazao da može zaustaviti proliferaciju stanica EAT u uvjetima in vitro, te da slabo povećava postotak stanica u apoptozi. Kombinacija s citostatikom bleomicinom i hipertermijom daje bolji antiproliferativni učinak koji se temelji na visokom postotku indukcije nekroze te potpunoj lizi stanica.Chemotherapy is one of the most advanced and successful actions in the fight against cancer. Chemotherapy is used to stop proliferation and spreading of cancer cells, as well as to initiate apoptosis in cancer cells. Due to its necrotic nature chemotherapy usually causes damager to nearby healthy tissue. Flavonoids already have shown their capability to fight cancer cells and to prevent some damage to healthy cells. In this research curcumin (1,7-bis(4-hidroksi-3-metoksifenil)hepta-1,6-dien-3,5-dion) was tested in vitro for its effect on Ehrlich ascites tumor (EAT) cells, their proliferation and the ability to initiate apoptosis/necrosis in the cells, and curcumins effect in interaction with bleomycin and hyperthermia. EAT was grown in Swiss albino mice, the cells were isolated on the 7th day, they were incubated in the culture medium, and treated with curcumin, bleomycin and hyperthermia. The antiproliferative effect of the test components was confirmed by a colorimetry assay (MTT assay) after a short incubation directly with bleomycin for 2 h and curcumin next 2 h at physiological (37 °C) or hyperthermal (43 °C) conditions and after the treatment of cells for 24 hrs. I analyzed the percentage of tumor cells in apoptosis and necrosis in flow cytometry and studied genotoxic effects using comet assay. Curcumin demonstrated the potential to inhibit the proliferation of EAT cells in vitro, and to slightly increase the percentage of cells in apoptosis. The combination with cytostatic bleomycin and hyperthermia provides a better anti-proliferative effect which is based on the high percentage induction of necrosis and complete cell lysis