EC359

The induction of TNBC cell migration and expression of programmed death-ligand 1 (PD-L1) by a recombinant LIF, along with attenuation by EC359, a LIF inhibitor, were investigated using Transwell assay and flow cytometry...FAP-positive CAFs overexpress genes like LIF, which promotes cell migration and PD-L1 expression. LIF inhibition reduces these effects, suggesting LIF as a potential therapeutic target in TB-associated TNBC progression and immunotherapy.

Our studies identify LIFR signaling as a critical vulnerability in Ras/Raf-mutant and low grade serous OCa. Further, it provides strong preclinical rationale for EC359 and trametinib combination therapy as a new therapeutic strategy for treating Ras/Raf-driven OCa and low-grade serous OCa.

In autochthonous murine model of PDAC, EC359 enhanced the therapeutic efficacy of gemcitabine and nab-paclitaxel, accompanied by an increase in dendritic cells but a reduction in T-regulatory cells. Thus, EC359 reduces PDAC cell stemness, stabilizes microtubule assembly, and reduces the immunosuppressive microenvironment to improve the efficacy of standard-of-care in PDAC.

EC359 (5 mg/kg/day) was effective in reducing the growth of the IBC KPL4 xenograft tumors. These findings demonstrates that LIFR inhibition promote ferroptosis-mediated cell death in IBC and that EC359 represent novel therapeutic for IBC treatment.

RNA-Seq analysis identified critical pathways modulated by LIF/LIFR signaling in diet-induced obesity mouse models. These findings suggest that adiposity contributes to TNBC progression via the activation of the LIF/LIFR pathway, and LIFR inhibition with EC359 represents a promising therapeutic approach for obesity-associated TNBC.

Consequently, immune cell infiltration was reduced in aortic plaques of EC359 treated mice compared to control mice. Conclusively, we demonstrated that LIF receptor is a potential therapeutic target in atherosclerosis by reducing plaque size, attributed to lower serum cholesterol levels, reduced endothelial activation and less immune cell infiltration in the plaque.

Additionally, EC359 therapy considerably improved tumor immunogenicity by robust CD45+ leukocyte tumor infiltration and polarizing tumor-associated macrophages (TAMs) toward M1 phenotype while showing no impact on normal T-, B-, and other immune cells. Collectively, our findings indicate that the LIF/LIFR autocrine loop plays an essential role in OCa progression and that EC359 could be a promising therapeutic agent for OCa.

Tumor progression was markedly inhibited by EC359 treatment in two different patient-derived xenograft models in vivo and patient-derived organoids ex vivo. Collectively, these results suggest LIFR inhibitor EC359 as a possible new small-molecule therapeutics for the management of Type II ECa.

Future research should focus on investigating LIF targets in combination with current standard-of-care chemotherapy, and immunotherapy can be a promising approach. Further, larger multicenter clinical trials are needed to define the use of LIF as a new biomarker in PDAC patients.

Further, treatment with EC359 significantly attenuated adipocyte-induced EEC progression in vivo. Collectively, our data support the premise that LIF/LIFR signaling plays an important role in obesity-driven EEC progression and the LIFR inhibitor EC359 has the potential to suppress adipocyte-driven tumor progression.