ABSTRACT
MicroRNA (miRNA) is a class of non-coding single-stranded small RNAs of about 22 nucleotides in length,which regulate the expression of related genes in post-transcriptional levels,including cell proliferation and differentiation,apoptosis and individual development.The miR-34 family (miR-34s) is a highly conserved microRNA family,which is widely found in arthropods,nematodes and mammals.Human miRNA-34s include miR-34a,miR-34b and miR-34c.A large number of studies have shown that miR-34s is closely related to the development and prognosis of pulmonary diseases,such as bronchopulmonary dysplasia,asthma,chronic obstructive pulmonary disease,lung cancer and pulmonary hypertension.This paper reviews the progresses of miR-34s and the diseases mentioned-above.