MicroRNA response to Snail overexpression in lung cancer cell lines

Analysis of four lung cancer cell lines transfected with a vector expressing the transcriptional repressor Snail versus a vector control. Aberrant Snail expression is known to induce an EMT program in lung cancers. Four lung cancer cell lines (H292, H358, H441, H1437) with stable overexpression of the human SNAI1 gene and vector expressing controls were collected at equal confluency with the miRNeasy Mini kit (Qiagen). One microgram of total RNA was labeled using miRCURY LNA™ microRNA Array Power Labeling kit by the UCLA Clinical Microarray Core. The labeled miRNAs were hybridized to Exiqon miRCURY LNA microRNA Array-6th Generation according to the manufacturer’s instructions. This array includes 927/648/351 human/mouse/rat miRNAs as well as 438 miRPlus miRNAs. The miRNA array slides were scanned using Axon GenePix 4000B scanner (Axon Instruments, Foster City, CA) and processed by using the GenePix Pro 6.0 software (Axon Instruments). The raw data were normalized by using a combination of housekeeping miRNA, spike-in miRNA and invariant endogenous miRNAs.