Interpretation of qRT-PCR results revealed that treatment of A-431 cancer cells with Y2O3NPs at concentrations of 7.47, 14.98 and 29.89 μg/ml significantly upregulated the expression level of apoptotic p53 and mitochondrial ND3 genes, while significantly downregulated the anti-apoptotic Bcl2 gene expression in a concentration-dependent manner compared to the expression level in control (untreated) A-431 cells (Table 5). Here, BCL2 is linked to cancer.