Introduction: Exosomes are extracellular vesicles, which are released from most cells, involved in cell-tocell communication. Exosomes contain membrane and cytosolic components such as proteins, lipids, messenger Ribonucleic Acids (mRNAs), and microRNAs. However, the existence of other types of RNAs in these exosomes is unknown.
Methods: In the present study, the presence of Natural Antisense Transcripts (NATs) transcribed from reverse strand deoxynucleic acids of genes in exosomes released from colorectal cancer SW480 cells were investigated using a sense/antisense custom microarray.
Results and Discussion: When signal intensities with values of more than 100 were selected, 6,218 NATs were detected in exosomes released from SW480 cells. Among them, NATs transcribed from transcription factor 7-like 1 genes, which had the lowest signal intensities, were detected using strandspecific reverse transcription-polymerase chain reaction. Thus, a large number of NATs as well as mRNAs and microRNAs are present in exosomes and are likely to be delivered to other cells.Author(s): Mitsuru Chiba