Modulation of gene expression by thymoquinone conjugated zinc oxide nanoparticles arrested cell cycle, DNA damage and increased apoptosis in triple negative breast cancer cell line MDA-MB-231.

Nanomedicines include the area of science that combines the drugs or diagnostic molecules using nanotechnology approach to improve its ability to target specific cells or tissues. Zinc oxide (ZnO) nanoparticles are known for its non-toxicity, biocompatibility and biosafety. Thymoquinone (TQ) is used in the present study from the seeds of (Black cumin seed). ZnO nanoparticles and TQ-ZnO (TQ coated ZnO) nanoparticles were synthesized and its characterization were analyzed using spectrophotometeric analysis and dose of the treatment groups (ZnO, TQ and TQ-ZnO nanoparticles) were optimized in our previous studies. Triple Negative Breast Cancer (TNBC) cells, MDA-MB-231 were exposed to 30 µg/ml dose of TQ coated ZnO nanoparticles which were synthesized and characterized. Their anticancer properties were validated by testing their ability to induce DNA damage, to inhibit cell proliferation, to induce apoptosis and arrest cell cycle. Modulation of gene expression and their intensities of the fluorogen reflecting the extent of gene expression were quantified using RT-PCR. Furthermore, the Human Breast Cancer PCR array profiles the expression of 84 genes and11 different biological pathways. The results revealed that the TQ-ZnO nanoparticles inhibited the proliferation of cells at synthesis phase and increased DNA damage, which further resulted in apoptosis. PCR array results showed that the combined effect have extensive applications in therapeutics. TQ-ZnO nanoparticles modulated the expression pattern of breast cancer associated genes in TNBC cells.