Marine fungal metabolite 1386A alters the microRNA profile in MCF-7 breast cancer cells

Marine fungal metabolite 1386A is a newly identified small molecular compound extracted from the mangrove fungus 1386A in the South China Sea. Preliminary experiments have demonstrated its amazing cytotoxity to cancer cells, while the mechanism remains poorly understood. microRNAs (miRNAs) are a newly identified class of small regulatory RNAs which play an important role in gene regulation at the post-transcriptional level. They usually function as oncogenes or tumor suppressors and are related to drug sensitivity and resistance. We aimed to test the hypothesis that the potential antineoplastic compound, 1386A, alters the miRNA profile in MCF-7 and whether its unknown mechanism may be predicted by analysis of the altered miRNA profile. Cell proliferation was analyzed by MTT assay. The alteration of the miRNA expression profile of MCF-7 cells was investigated using advanced microarray technology. Silico analysis using TargetScan was used to predict the putative targeted transcripts encoding the dysregulated miRNAs. 1386A inhibited MCF-7 cell proliferation in a time- and dose-dependent manner (the IC50 value at 48 h was 17.1 µmol/l). 1386A (17.1 µmol/l) significantly altered the global miRNA expression profile of the MCF-7 cells at 48 h. Forty-five miRNAs were differentially expressed in MCF-7 cells. Target prediction suggested that these miRNAs potentially target many oncogenes and tumor-suppressor genes associated with cancer development, progression and metastasis. The promising antineoplastic compound marine fungal metabolite 1386A alters the miRNA profiles of MCF-7 breast cancer cells. Analyzing the alteration of the miRNA profile caused by this potential antineoplastic compound may help to predict the unknown mechanism of 1386A.