Differential regulation of the interferon induced gene ISG12A by serum from healthy and preeclamptic pregnancies

Identification of genes dysregulated by elevation of microRNA-210 levels in human trophoblasts cell line, Swan 71

PROBLEM

Preeclampsia is a serious pregnancy disorder characterized by gestational hypertension and proteinuria. miR-210 is significantly overexpressed in the placentas of preeclampsia patients.

METHOD OF STUDY

Swan 71 cells, first-trimester human trophoblastic cell line, were transfected with hsa-miR-210-3p oligonucleotides by electroporation. Altered transcriptome was analyzed using microarray technique. Differentially expressed genes (DEGs) were clustered into Gene Ontology annotation biological processes. The extent of physical interaction between miR-210 and IGFBP3 mRNA was assessed via ribonucleoprotein immunoprecipitation.

RESULTS

Microarray analysis showed 408 DEGs by elevated levels of miR-210 in Swan 71 cells. These genes were enriched in several biological processes involved in the pathogenesis of preeclampsia. IGFBP3, a gene associated with preeclampsia pathophysiology, was validated as a target gene of miR-210.

CONCLUSION

We have demonstrated that elevated miR-210 levels in human trophoblast alter the expression profile of known preeclampsia-associated genes, and of gene targets involved in various biological processes essential to preeclampsia progression.

Antihypertensive therapy in pre-eclampsia: effects of plasma from nonresponsive patients on endothelial gene expression

Aim: Over 40% of patients with pre-eclampsia are nonresponsive to antihypertensive therapy, but the underlying mechanisms are unknown. We examined the effects of plasma from nonresponsive and responsive patients on endothelial gene expression. Patients & methods: PCR array was performed in human umbilical vein endothelial cells (HUVEC) incubated with plasma from nonresponsive (n = 4) and responsive (n = 4) patients. Gene networks and interactions with antihypertensive drugs used in pre-eclampsia were identified by Ingenuity Pathway Analysis. Results: Nifedipine and hydralazine act by upregulate or downregulate genes found to be downregulated or upregulated in HUVEC incubated with plasma from nonresponsive patients. Conclusion: Our novel findings suggest that plasma from nonresponsive and responsive patients evoke different responses in HUVEC, and might advance the pharmacogenomics research in pre-eclampsia.

Folic acid mediates activation of the pro-oncogene STAT3 via the Folate Receptor alpha

The signal transducer and activator of transcription 3 (STAT3) is a well-described pro-oncogene found constitutively activated in several cancer types. Folates are B vitamins that, when taken up by cells through the Reduced Folate Carrier (RFC), are essential for normal cell growth and replication. Many cancer cells overexpress a glycophosphatidylinositol (GPI)-anchored Folate Receptor α (FRα). The function of FRα in cancer cells is still poorly described, and it has been suggested that transport of folate is not its primary function in these cells. We show here that folic acid and folinic acid can activate STAT3 through FRα in a Janus Kinase (JAK)-dependent manner, and we demonstrate that gp130 functions as a transducing receptor for this signalling. Moreover, folic acid can promote dose dependent cell proliferation in FRα-positive HeLa cells, but not in FRα-negative HEK293 cells. After folic acid treatment of HeLa cells, up-regulation of the STAT3 responsive genes Cyclin A2 and Vascular Endothelial Growth Factor (VEGF) were verified by qRT-PCR. The identification of this FRα-STAT3 signal transduction pathway activated by folic and folinic acid contributes to the understanding of the involvement of folic acid in preventing neural tube defects as well as in tumour growth. Previously, the role of folates in these diseases has been attributed to their roles as one-carbon unit donors following endocytosis into the cell. Our finding that folic acid can activate STAT3 via FRα adds complexity to the established roles of B9 vitamins in cancer and neural tube defects.