Konditioniertes Medium von Fettgewebsstromazellen reduziert die Cisplatin-induzierte Apoptose proximaler tubulärer Epithelzellen durch Herunterregulierung von miR-181a-5p
Eleonora Scaccia (Mannheim / DE), Isabell Moskal (Mannheim / DE), Francesca Pagano (Rom / IT), Harald Klüter (Mannheim / DE), Karen Bieback (Mannheim / DE)
Cisplatin is a widely used effective cancer chemotherapeutic drug. However, nephrotoxicity is one of its limiting side effects. Cisplatin nephrotoxicity, especially apoptosis of proximal epithelial cells, appears associated with aberrant expression of microRNAs (miRNAs). By trophic factors, adipose stromal cells (ASC) exert a protective effect inhibiting apoptosis and promoting tissue regeneration. We hypothesize that this protective effect acts by modulating the miRNA expression in injured renal cells by miRNA-mediated post-transcriptional gene regulation.
To mimic in vitro injury and ASC-mediated protection, proximal tubule epithelial cells (PTECs) were treated with cisplatin for 1h and then treated for a further 23h with cisplatin plus ASC-derived conditioned medium (CM-ASC). Viability, migratory capacity in a scratch wound healing assay, apoptosis and p53 expression were assessed. Further, mRNAs prepared from PTECs treated with/without cisplatin and with/without ASC-CM were assessed by small-RNASeq. Candidate miRNAs were functionally validated in apoptosis assays.
Cisplatin-treated PTECs reduced viability, migratory capacity and induced apoptosis in line with increased p53 expression. ASC-CM ameliorated this cisplatin toxicity; especially migratory activity and apoptosis with p53 levels back to physiological levels. Small-RNAseq analysis identified differentially expressed miRNAs in all groups, particularly miR-181a-5p, known to play a role in apoptosis. Functional testing revealed that inhibition of miR-181a-5p led to a reduction in apoptosis accentuated by ASC-CM. In contrast, a miR-181a mimic did not affect cellular apoptosis.
Our results demonstrate that ASC-CM per se exerts a protective effect reducing cisplatin cytotoxicity in renal proximal tubule cells. ASC-CM counteracted the change in expression of microRNA induced by cisplatin and identified miR-181a as a possible therapeutic target to prevent cisplatin-induced cytotoxicity.
This project has received funding from the European Union"s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 813839.