mature piRNAs expression profile in human bronchial epithelial (HBE) and non-small cell lung cancer (NSCLC) cells. Homo sapiens

To elucidate potential roles of piRNA in lung cancer, we analyzed global piRNA expression profiles in 8 NSCLC and 3 HBE cell lines. RNA-seq results showed that >99% of the approximately 4.5 million reads were between 26 and 32 bases. Most of the piRNA loci are represented by two or more identical reads. We observed a total 555 expressed mature piRNAs, distributed among chromosomes and mitochondria with bias in chromosomes 1 and 6. 99% of the piRNAs are mapped to intergenic regions (64%) or introns (35%) and 1% to exons. Of the 555 mature piRNAs, 260 (47%) have been recorded in NCBI whereas 295 (53%) are novel. These results provide a comprehensive view of piRNA expressed in human bronchial epithelial cells and NSCLC cells. Overall design: To get the purified mature piRNAs, small RNA (<200nt) was separated from total RNAs firstly, and then piRNA were purified in one nucleotide resolution gel. A unique 6 nt barcode for every cell line to distinguish each reads from each specific cell line, and the right size of small RNAs were used library for Illumina sequencing.