Abstract
Purpose :
Thyroid eye disease (TED) is a condition characterized by proptosis, diplopia, eyelid retraction, and in severe cases, vision loss. Current medical therapies, which primarily consist of steroids and immunomodulation, have variable success and high relapse rates. Alternatively, we hypothesize that targeting the pathologic gene signature in TED with drug-based treatments that reverse this gene signature will improve treatment efficacy. In this study, we identified and evaluated the efficacy of LINCS-predicted small molecules to revert the disease signature in TED orbital adipose stem cells (OASC) in vitro.
Methods :
OASCs were isolated from patients with and without TED (4 non-TED, 5 TED). Differentially expressed genes (DEG) identified via RNA sequencing were inputted into LINCS L1000 to identify candidate small molecules that may re-normalize pathologic gene expression. OASCs were treated in vitro with 6 different small molecules (Torin 2, PX12, Withaferin A, Isoliquiritigenin, Mitoxantrone, and MLN8054) for 7 days. Key DEGs and adipogenicity markers were analyzed via qPCR. OASCs were differentiated into adipocytes and stained with Oil Red O (OD 490nm) following 14-day treatment.
Results :
RNA sequencing identified 54 differentially expressed genes (p<0.0005) in TED OASCs. The expression of several of the most upregulated genes, including IRX1, HOXB2/3, S100B, and KCNA4, was significantly reduced in TED OASCs after treatment (p<0.05). In the treated TED adipocytes (n=4), all tested small molecules yielded significant reduction (p<0.05) in Oil Red O staining. In the treated non-TED adipocytes (n=3), half of the drugs yielded significant reduction in Oil Red O staining. In these adipocytes, the treated TED group yielded greater adipogenic reduction in all 6 drug treatments than in the treated non-TED group.
Conclusions :
Our study demonstrates that combining disease-specific gene expression signatures with LINCS small molecule perturbagen-response profiles can identify promising preclinical drug candidates for TED. Our LINCS-predicted drugs were able to re-normalize the expression of DEGs in TED OASCs, exhibit correlating morphologic and adipogenic changes, and demonstrate preferential effect in diseased cells. These findings may offer insight into future potential therapeutic options for TED.
This is a 2020 ARVO Annual Meeting abstract.