Loss of legumain induces premature senescence and mediates aging-related renal fibrosis.

Aging is an independent risk factor for acute kidney injury and subsequent chronic kidney diseases, while the underlying mechanism is still elusive. Here, we found that renal tubules highly express a conserved lysosomal endopeptidase, legumain, which is significantly downregulated with the growing of age. Tubule-specific legumain-knockout mice exhibit spontaneous renal interstitial fibrosis from the 3rd month.

Cancer-derived exosomal miR-138-5p modulates polarization of tumor-associated macrophages through inhibition of KDM6B.

Differential activation of macrophages correlates closely with tumor progression, and the epigenetic factor lysine demethylase 6B (KDM6B, previously named JMJD3) mediates the regulation of macrophage polarization through an unknown mechanism. We developed a suspension coculture system comprising breast cancer cells and macrophages and used RT-qPCR and western blotting to measure expression. Bioinformatics and luciferase reporter assays were used to identify candidate microRNAs of cancer cells responsible for the downregulation of KDM6B.

Legumain promotes tubular ferroptosis by facilitating chaperone-mediated autophagy of GPX4 in AKI.

Legumain is required for maintenance of normal kidney homeostasis. However, its role in acute kidney injury (AKI) is still unclear. Here, we induced AKI by bilateral ischemia-reperfusion injury (IRI) of renal arteries or folic acid in lgmn and lgmn mice.

Legumain-deficient macrophages promote senescence of tumor cells by sustaining JAK1/STAT1 activation.

Macrophages serve as the first line of communication between tumors and the rest of the immune system, and understanding the interplay between macrophage and tumor cells is essential for developing novel macrophage-based strategy against tumor. Here, we show that deletion of legumain in macrophages activates senescence of tumor cells. Macrophage derived IL-1β mediates the pro-senescent effect of Lgmn macrophages since blockage of IL-1β reverses the senescence phenotype in both a coculture model of macrophage and tumor cells and an orthotopic mouse model of breast cancer.

Asparaginyl endopeptidase induces endothelial permeability and tumor metastasis via downregulating zonula occludens protein ZO-1.

Zona occludens-1 (ZO-1) is a key component of tight junctions that govern the function of the endothelial barrier against tumor metastasis. Factors secreted by tumor cells contribute to the maintenance of tumor vascular networks. How tumor cell-derived protein signals regulate ZO-1 expression is unclear.

Legumain, an asparaginyl endopeptidase, mediates the effect of M2 macrophages on attenuating renal interstitial fibrosis in obstructive nephropathy.

Two distinct macrophage phenotypes contribute to kidney injury and repair during the progression of renal interstitial fibrosis; proinflammatory (M1) and antiinflammatory (M2) macrophages. Legumain, an asparaginyl endopeptidase of the cysteine protease family, is overexpressed in macrophages in some pathological conditions. However, the macrophage subtype and function of macrophage-derived legumain remains unclear.