miR‑1343‑3p inhibits autophagy by directly targeting ATG7 in multiple myeloma cells.

Multiple myeloma (MM) is the second most common type of hematological malignancy globally. Despite application of several new drugs, such as daratumumab, bortezomib/lenalidomide/dexamethasone, in combination with hematopoietic stem cell transplantation, overall prognosis remains poor and the pathological mechanism of MM is still unknown. The present study used TargetScan to predict autophagy-related 7 (ATG7) as a candidate target gene of microRNA (miR)-1343-3p and confirmed the interaction between miR-1343-3p and the ATG7 3' untranslated region (3'UTR) using a dual-luciferase reporter assay. In U266 and RPMI-8226 MM cell lines, miR-1343-3p mimic transfection decreased mRNA and protein levels of ATG7, while miR-1343-3p inhibition increased ATG7 expression levels using reverse transcription-qPCR and western blot analysis. miR-1343-3p mimic transfection inhibited U266 and RPMI-8226 cell survival. Finally, miR-1343-3p regulated ATG7 and autophagy in MM cells using western blot analysis. The present findings suggested that miR-1343-3p may regulate ATG7 and autophagy by directly targeting the 3'UTR of ATG7. To the best of our knowledge, there are no direct data showing the roles of miR-1343-3p in development of MM; however, miR-1343-3p may be considered a potential target for MM treatment.