Nanobiotechnology for health-care

Proliferative activity of Ehrlich carcinoma cells after use of nanocomplexes

Goltsev A.M.1, Malyukin Yu.V.2  , Babenko N.M.1, Gaevska Yu.O.1, Bondarovych M.O.1, Dubrava T.G.1, Ostankov M.V.1, Klochkov V.K.2
1  Institute for Problems of Cryobiology & Cryomedicine of the National Academy of Sciences of Ukraine, Pereyaslavska Str. 23, 61016 Kharkiv, Ukraine
E-mail:  cryo@online.kharkov.ua
2 Institute for Scintillation Materials of the National Academy of Sciences of Ukraine, 60 Nauki ave., 61001 Kharkiv, Ukraine

Developing the criteria for the effective anticancer therapy is a key task of oncology. One of them may be the determination of proliferative status of tumor cells using the Ki-67 marker, a nuclear protein present in actively dividing cells. The aim of this research was to evaluate the effect of nanocomplexes (NCs) containing spherical GdYVO4:Eu3+ nanoparticles and cholesterol on proliferative activity of cells of Ehrlich ascites carcinoma (EAC).The objects of the study were cells of total population of EAC and CD44+ fraction isolated from it by magnetic separation (BDTM Іmagnet, USA). Both types of cells were incubated with NCs for 3 hours, after that they were intraperitoneally injected into BALB / c mice at a dose of 3x106 cells / mouse. After 7 days, the volume of ascites and total number of cells of peritoneal cavity (PC), percentage of cells among them positive on markers Ki-67 and CD44 were determined with FACS Calibur flow cytometer (BD, USA). In all groups, the number of surviving animals was assessed. The EAC population and CD44+ fractions without treatment with NCs.
It was shown that NCs to a greater extent inhibited the proliferative activity of CD44+ cells than the cells of total EAC population, which was confirmed by a decrease in both  total number of cells in PC and content of Ki-67+ cells among them. Inhibition of tumor growth was accompanied with prolongation of life of tumor-bearing mice. The results obtained indicate the ability of NCs to selectively inhibit the proliferation of the most highly proliferating Ki-67+ cells, predominantly present in CD44+ fraction, and monitoring their content can be a criterion for the effectiveness of this kind of therapy.