Effectiveness of Natural Killer (NK) Cells in Peripheral Blood Stem-Cell towards Expression of EZH2, Ki-67 and Apoptosis in Retinoblastoma (RB) Cells Culture

Abstract A natural killer (NK) cell is a large granular lymphocyte having a cytotoxic activity against malignant tumor cells in the cellular immune response. NK cells play an important role to inhibit the metastasis of tumor and express glikoprotein molecule antigen (IgG) and variable cytotoxic factors like perforin, granzyme, cytolysin such as TNF-α against retinoblastoma cells. The aim of the study was to investigate the role of Natural Killer Cells (NK cells) as an alternative therapy, especially in cases of retinoblastoma. It is highly expected that the study can be used as a starting point in determining the strategic therapy, e.g. the cell targeted therapy to inhibit EZH2 and retinoblastoma cell proliferation. There were 2 groups of retinoblastoma cell cultures in this study, the groups of control (n=10) and exposure (n=10). The control group was a group of retinoblastoma cell cultures that did not get any therapy, while the exposure group was a group of retinoblastoma cell cultures with NK Cell exposure in vitro for 3 days. The data obtained were analyzed using the T- test and Pearson Correlation. In T-test, the results of the two groups indicated a significant difference in the positive expression of cell count of EZH2, Ki-67 and Apoptotic cells. The Pearson Correlation test showed that the expression of EZH2 was statistically negative significant (α: -0.930; p<0.05) towards the apoptotic cells expression. While in the proliferation cell expression (Ki-67) towards the apoptotic cell expression, the correlation was significantly negative (α: -0,868; p<0.05). The study showed that NK cells played an important role in the aggressiveness of RB cell cultures by changing the expression of EZH2, Ki-67 and apoptosis in RB cells. It is expected that the research can be used as a reference to determine the strategic therapy in retinoblastoma. Keywords: NK cells, retinoblastoma, EZH2, proliferation, apoptosis