miR-137 upregulation decreases levels of PRKAA1 in HTR-8/SVneo cells. HTR-8/SVneo cells were infected with lentiviral vectors and miR-137 and PRKAA1 gene expression levels were measured using reverse transcription-quantitative polymerase chain reaction analysis, with hsa-u6 and β-actin as internal controls, respectively. Protein levels of PRKAA1 (~62 kDa) were detected by western blot analysis, and β-actin (~43 kDa) was used as an internal control. (A) miR-137 was upregulated in LV-miR-137 HTR-8/SVneo cells. (B) Gene expression level of PRKAA1 was downregulated in the LV-miR-137 group. (C) Western blot analysis of PRKAA1. (D) Protein level of PRKAA1 was decreased in miR-137-overexpressing HTR-8/SVneo cells. Data are expressed as the mean ± standard error of the mean; statistical significance was determined using Student's t-test, *P<0.05, **P<0.01. Ctrl, control; NS, no significant difference; miR-137, microRNA-137; PRKAA1 protein kinase AMP-activated catalytic subunit α1; LV, lentiviral vector; NC, negative control.