Everolimus-induced epithelial to mesenchymal transition (EMT) in bronchial/pulmonary cells: when the dosage does matter in transplantation.

Abstract

BACKGROUND:

Everolimus (EVE) is a mammalian target of rapamycin inhibitor (mTOR-I) widely used in transplantation that may determine some severe adverse events, including pulmonary fibrosis. The pathogenic mechanism of mTOR-I-associated pulmonary toxicity is still unclear, but epithelial to mesenchymal transition (EMT) of bronchial/pulmonary cells may play a role.

METHODS:

Three cell lines-human type II pneumocyte-derived A549, normal bronchial epithelial, and bronchial epithelial homozygous for the delta F508 cystic fibrosis-causing mutation-were treated with EVE or tacrolimus at different concentrations. Real-time polymerase chain reaction and immunofluorescence were used to evaluate mRNA and protein levels of EMT markers (alpha-SMA, vimentin, fibronectin). Subsequently, in 13 EVE- and 13 tacrolimus-treated patients we compared the rate of lung fibrosis, estimated by an arbitrary pulmonary fibrosis index score (PFIS).

RESULTS:

Biomolecular experiments demonstrated that high doses of EVE (100 nM) up-regulated EMT markers in all cell lines at both gene- and protein level. High concentrations of EVE were also able to reduce the mRNA levels of epithelial markers (E-cadherin and ZO-1) and to induce the phosphorylation of AKT. In the in vivo part of the study, PFIS was significantly higher in the EVE-group than the tacrolimus-group (p = 0.03) and correlated with trough levels (R2 = 0.35).

CONCLUSIONS:

Our data reveal, for the first time, a dose-dependent EVE-induced EMT in airway cells. They suggest that clinicians should employ, wherever possible, low dosages of mTOR-Is in transplant recipients, assessing periodically their pulmonary function.

• Authors: Paola Tomei, Valentina Masola, Simona Granata, Gloria Bellin, Pierluigi Carratù, Miriam Ficial, Valentina Anna Ventura, Maurizio Onisto, Onofrio Resta, Giovanni Gambaro, Marco Chilosi, Antonio Lupo, Gianluigi Zaza
• Journal: Journal of nephrology (J Nephrol) Vol. 29 Issue 6 Pg. 881-891 (Dec 2016) ISSN: 1724-6059 [Electronic] Italy
• PMID: 27026415 (Publication Type: Comparative Study, Journal Article)

Chemical References

• ACTA2 protein, human
• Actins
• Fibronectins
• Immunosuppressive Agents
• Protein Kinase Inhibitors
• RNA, Messenger
• Vimentin
• Everolimus
• MTOR protein, human
• Proto-Oncogene Proteins c-akt
• TOR Serine-Threonine Kinases
• Tacrolimus

Topics

• A549 Cells
• Actins (genetics, metabolism)
• Adult
• Aged
• Alveolar Epithelial Cells (drug effects, metabolism, pathology)
• Bronchi (drug effects, enzymology, pathology)
• Dose-Response Relationship, Drug
• Epithelial-Mesenchymal Transition (drug effects)
• Everolimus (adverse effects)
• Female
• Fibronectins (genetics, metabolism)
• Gene Expression Regulation
• Humans
• Immunosuppressive Agents (adverse effects)
• Male
• Middle Aged
• Organ Transplantation (adverse effects)
• Phosphorylation
• Protein Kinase Inhibitors (adverse effects)
• Proto-Oncogene Proteins c-akt (metabolism)
• Pulmonary Fibrosis (chemically induced, enzymology, genetics, pathology)
• RNA, Messenger (genetics, metabolism)
• Risk Assessment
• Signal Transduction (drug effects)
• TOR Serine-Threonine Kinases (antagonists & inhibitors, metabolism)
• Tacrolimus (adverse effects)
• Vimentin (genetics, metabolism)