The MyD88 inhibitor TJ-M2010-2 suppresses proliferation, migration and invasion of breast cancer cells by regulating MyD88/GSK-3ß and MyD88/NF-κB signalling pathways.

MyD88 has been implicated in the tumourigenesis, metastasis and recurrence of breast cancer (BC). Here we utilized TJ-M2010-2 (TJ), an inhibitor of MyD88 homodimerimerization, and siMyD88 to suppress the function of MyD88 in MCF-7 and MDA-MB-231 cells. BC cells were treated in vitro and xenografted into nude mice to generate a model in vivo. TJ inhibited BC cell growth by impeding proliferation rather than by promoting apoptosis in vitro. Additionally, TJ and siMyD88 significantly attenuated cell migration and invasion, inhibited EMT-like progression and reduced cytokine (IL-6, IL-8, TGF-ß1 and TNF-α) secretion induced by LPS. In vivo, TJ significantly hindered tumour growth in mice. Notably, TJ also decreased the secretion of IL-6, IL-8, TGF-ß1, and TNF-α and M2 macrophage infiltration in the tumour microenvironment. The expression of MyD88, TRAF6, NF-κB p65, Snail, MMP-2, MMP-9, p-GSK-3ß and p-Akt was significantly downregulated by TJ in BC cells and tumour tissues. Collectively, these results suggest that a MyD88 inhibitor (TJ) may be a promising therapeutic modality for treating BC patients.

A Novel Inhibitor of Homodimerization Targeting MyD88 Ameliorates Renal Interstitial Fibrosis by Counteracting TGF-ß1-Induced EMT in Vivo and in Vitro.

BACKGROUND/AIMS: The TLR/MyD88/NF-κB signaling pathway has been successfully used to treat renal interstitial fibrosis (RIF). However, the exact therapeutic mechanism is still unknown. Here, we assessed the therapeutic efficacy of TJ-M2010-2, a small molecular compound that inhibits MyD88 homodimerization, in RIF induced by ischemia reperfusion injury (IRI). METHODS: In vivo, RIF was induced in mice by IRI, and the mice were prophylactically treated with TJ-M2010-2. In vitro, HK-2 cells were incubated with TGF-ß1 to induce EMT, and the cells were pretreated with TJ-M2010-2. RESULTS: We found that, compared with the IRI group, the TJ-M2010-2 group showed marked attenuation of RIF and renal function injury; decreased expression of TGF-ß1, α-SMA, vimentin, MMP2 and MMP9; and increased E-cadherin expression. Furthermore, TGF-ß1-induced EMT was blocked by TJ-M2010-2 in HK-2 cells, as evidenced by blocked morphologic transformation, restored E-cadherin expression and inhibited α-SMA expression. In addition, compared to the TGF-ß1 group, the TJ-M2010-2 group showed profound inhibition of the expression of TRAF6, p65 and Snail and upregulation of the expression of IκBα. CONCLUSION: This MyD88 inhibitor may be a potential therapeutic agent to ameliorate RIF.