Metastasis-associated lung adenocarcinoma transcript 1 induces methyl-CpG-binding domain protein 4 in mice with recurrent spontaneous abortion caused by anti-phospholipid antibody positivity.

INTRODUCTION

Antiphospholipid syndrome is an autoimmune disease characterized by pregnancy-related morbidity, related to persistent positivity of antiphospholipid antibodies (APL). One of the characteristics of pregnancy-related morbidity in patients with antiphospholipid syndrome is recurrent spontaneous abortion (RSA). This study aimed to examine the mechanism through which metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) regulates methyl-CpG-binding domain protein 4 (MBD4) expression in APL-positive RSA.

METHODS

Clinical samples were subjected to microarray analysis to filter differentially expressed genes. RSA mice with APL positivity were generated, followed by adenoviral vector injection to artificially upregulate MALAT1. The effects of MALAT1 on the biological behavior of trophoblast cells were assessed. The downstream mechanism of MALAT1 was analyzed using subcellular fractionation and bioinformatics prediction, and the relationship between MALAT1 and CREB binding protein (CREBBP) or MBD4 was investigated in trophoblast cells.

RESULTS

MALAT1 was downregulated in APL-positive RSA patients. MALAT1 was predominantly localized in the nucleus and recruited CREBBP to mediate the MBD4 transcription. In the APL-positive RSA mice overexpressing MALAT1, the expression of soluble Fms-related tyrosine kinase 1 and anticardiolipin antibody and the embryonic resorption rate were decreased, indicating that MALAT1 reduced the occurrence of RSA in mice. Moreover, MALAT1 enhanced proliferation, migration, and invasion of trophoblast cells through recruiting CREBBP to promote MBD4 expression. Silencing of CREBBP or MBD4 increased embryonic resorption rate in RSA mice overexpressing MALAT1.

DISCUSSION: MALAT1 suppresses APL-positive RSA by promoting MBD4 transcription through recruitment of CREBBP to the MBD4 promoter region.