HDGF and neoplasm: The aberrant expression of miRNAs regulates tumourigenesis, angiogenesis and tumour metastasis.1, 4 For example, down‐regulation of the let‐7 miRNA family was associated with a poor prognosis in patients with NSCLC.5 miRNA‐16 inhibits NSCLC cell growth and motility by targeting hepatoma‐derived growth factor (HDGF).6 miRNA‐146a suppresses cell growth by targeting EGFR.7 However, whether miR‐34b‐3p is involved in NSCLC tumour growth and its functional role remain elusive.