Signal transducer and activator of transcription 3 (STAT-3) and zinc finger protein (Gli-2) are pro-fibrotic molecules which are involved in pulmonary fibrosis, and it was found that circRNA-662 and circRNA-949 have sponge like activity against miR-29b which interacts with STAT-3 and Gli-2. This evidence concerns the gene STAT3 and pulmonary fibrosis.