GLPG-0187

The role of increased smooth muscle cell (SMC) integrin αv signaling in Marfan syndrome (MFS) aortic aneurysm remains unclear. Herein, we examine the mechanism and potential efficacy of integrin αv blockade as a therapeutic strategy to reduce aneurysm progression in MFS.

Induced pluripotent stem cells (iPSCs) were differentiated into aortic SMCs of the second heart field (SHF) and neural crest (NC) lineages, enabling in vitro modeling of MFS thoracic aortic aneurysms. The pathological role of integrin αv during aneurysm formation was confirmed by blockade of integrin αv with GLPG0187 in Fbn1C1039G/+ MFS mice.

iPSC–derived MFS SHF SMCs overexpress integrin αv relative to MFS NC and healthy control SHF cells. Furthermore, integrin αv downstream targets (FAK [focal adhesion kinase]/Akt Thr308 /mTORC1 [mechanistic target of rapamycin complex 1]) were activated, especially in MFS SHF. Treatment of MFS SHF SMCs with GLPG0187 reduced p-FAK/p-Akt Thr308 /mTORC1 activity back to control SHF levels. Functionally, MFS SHF SMCs had increased proliferation and migration compared to MFS NC SMCs and control SMCs, which normalized with GLPG0187 treatment. In the Fbn1C1039G/+ MFS mouse model, integrin αv, p-Akt Thr308 , and downstream targets of mTORC1 proteins were elevated in the aortic root/ascending segment compared to littermate wild-type control. Mice treated with GLPG0187 (age 6–14 weeks) had reduced aneurysm growth, elastin fragmentation, and reduction of the FAK/Akt Thr308 /mTORC1 pathway. GLPG0187 treatment reduced the amount and severity of SMC modulation assessed by single-cell RNA sequencing.

The integrin αv-FAK-Akt Thr308 signaling pathway is activated in iPSC SMCs from MFS patients, specifically from the SHF lineage. Mechanistically, this signaling pathway promotes SMC proliferation and migration in vitro. As biological proof of concept, GLPG0187 treatment slowed aneurysm growth and p-Akt Thr308 signaling in Fbn1C1039G/+ mice. Integrin αv blockade via GLPG0187 may be a promising therapeutic approach to inhibit MFS aneurysmal growth.

Colorectal cancer is the third leading cause of cancer-related death and the third most common cause of cancer. As the five-year survival with advanced metastatic colorectal cancer (mCRC) is 14%, new treatment strategies are needed. Immune checkpoint blockade, which takes advantage of an individual's immune system to fight cancer, has an impact in the clinic; however, for CRC, it is only effective and approved for treating mismatch repair (MMR)-deficient cancer. Moreover, long-term outcomes in MMR-deficient mCRC suggest that most patients are not cured and eventually develop therapy resistance. We hypothesized that targeting TGF-β signaling may enhance immune-mediated T-cell killing by MMR-deficient CRC cells. Using GLPG-0187, an inhibitor of multiple integrin receptors and TGF-β, we demonstrate minimal cytotoxicity against MMR-deficient HCT116 or p53null HCT116 human CRC cells. GLPG-0187 promoted significant immune cell killing of the CRC cells by TALL-104 T lymphoblast cells and reduced phosphoSMAD2 in HCT116 p53-null cells either in the absence or presence of exogenous TGF-β. We observed a reduction in CCL20, CXCL5, prolactin, and TRAIL-R3, while GDF-15 was increased in TALL-104 cells treated with a T-cell activating dose of GLPG-0187 (4 µM). Our results suggest that TGF-β signaling inhibition by a general integrin receptor inhibitor may boost T-cell killing of MMR-deficient colorectal cancer cells and suggest that a combination of anti-GDF-15 in combination with TGF-β blockade be further investigated in the treatment of MMR-deficient mCRC. Our results support the development of a novel immune-based therapeutic strategy to treat colorectal cancer by targeting the TGF-β signaling pathway through integrin receptor blockade.