Objective: In this study, we aimed to compare gene expression levels in myometrial tissues and serum obtained from pregnant women undergoing cesarean section (CS) with and without uterine contractions. The myometrial activator protein-1 (AP-1) transcription factor family (JUN, FOS, and fos-related antigen-2 [FOSL2]) was investigated as a contraction-related transcriptional marker in maternal circulation to predict labor timing.
Methods: Samples were obtained from pregnant women who underwent CSs. Contractions were observed in the experimental group (n=10), whereas no contractions were observed in the control group (n=10). Gene expression of JUN, FOS, and FOSL2 was analyzed in serum and myometrial samples using droplet digital polymerase chain reaction, and statistical analysis was performed using GraphPad software (COMPANY, CITY, STATE, COUNTRY).
Results: Given the non-normal distribution of the data, the levels of JUN, FOS, and FOSL2 gene expression increased in the CS group with uterine contractions. However, this increase was not statistically significant in either the tissue or serum samples. Nevertheless, the correlation of JUN messenger ribonucleic acid expression between maternal circulation and myometrial tissue was statistically significant in the CS group with uterine contractions (P<0.01).
Conclusion: This is the first study to investigate the expression of AP-1 transcription factors in matched tissue and serum samples in relation to uterine contractility. The increased expression levels of JUN, FOS, and FOSL2 in the CS group with uterine contractions suggest that these genes may play a key role in the initiation or propagation of human labor. This research demonstrates that the uterine contraction-associated transcription factor AP-1 has potential as a biomarker for labor timing in maternal circulation.