Aims: Considered as one of the marine resources and due to their effective compounds, cyanobacteria activate the cell death process in cancer cells and, thus, may be used as a new source. The aim of the current research was to evaluate the effect of oscillatoria cyanobacterium extract on breast cancer cell line and NM23 gene expression.
Materials and Methods: In the present experimental study, oscillatoria cyanobacterium was cultured in a negative zayander medium at 26°C to 28°C with a light intensity of 350 to 3500lux, under 12-hour lighting and 12-hour darkness, and the MCF-7 cell line was prepared. Breast cancer cells were treated by hydroalcoholic extracts of oscillatoria with different concentrations. The effect of extract on cell survival was evaluated by MTT assay and the effect of the extract on the changes of NM23 gene expression was investigated by Real-Time PCR.
Findings: The morphology of MCF-7 cell line showed that the oscillatoria cyanobacterium extract significantly altered the treated cells compared with control cells. The survival of cells decreased with increasing concentration, and there was a significant difference compared to the control sample. After 24 hours, the extract inhibited 50% cell survival at a concentration of 0.6mg/ml (p<0.001). The NM23 gene expression significantly increased over a 24-hour period compared with the control sample.

Conclusion: Oscillatoria Cyanobacterium extract decreases the breast cancer cell line and increases the NM23 gene expression.