ILEI is an important intermediate participating in the formation of TGF-β1-induced renal tubular EMT

Proteomic research on new urinary biomarkers of renal disease in canine leishmaniosis: Survival and monitoring response to treatment

The objective of our study was to search for survival biomarkers (SB) and treatment response monitoring biomarkers (TRMB) in the urinary proteome of dogs with renal disease secondary to canine leishmaniosis (CanL), using UHPLC-MS/MS. The proteomic data are available via ProteomeXchange with identifier PXD042578. Initially, a group of 12 dogs was evaluated and divided into survivors (SG; n = 6) and nonsurvivors (NSG; n = 6). A total of 972 proteins were obtained from the evaluated samples. Then, bioinformatic analysis reduced them to 6 proteins like potential SB increased in the NSG, specifically, Haemoglobin subunit Alpha 1, Complement Factor I, Complement C5, Fibrinogen beta chain (fragment), Peptidase S1 domain-containing protein, and Fibrinogen gamma chain. Afterwards, SG was used to search for TRMB, studying their urine at 0, 30, and 90 days, and 9 proteins that decreased after treatment were obtained: Apolipoprotein E, Cathepsin B, Cystatin B, Cystatin-C-like, Lysozyme, Monocyte differentiation CD14, Pancreatitis-associated precursor protein, Profilin, and Protein FAM3C. Finally, enrichment analysis provided information about the biological mechanisms in which these proteins are involved. In conclusion, this study provides 15 new candidate urinary biomarkers and an improved understanding of the pathogenesis of kidney disease in CanL.

High-throughput data on circular RNA reveal novel insights into chronic glomerulonephritis

BACKGROUND

Circular RNAs (circRNAs), a unique novel type of RNA, have been widely reported to be involved in physiologic and pathologic processes in humans. However, the exact molecular pathogenesis of circRNAs in chronic glomerulonephritis (CGN) is far from clear.

OBJECTIVE

This paper aims to evaluate the specific expression profile of circRNAs in renal cortex tissues from Adriamycin-induced CGN rats.

METHODS

CircRNAs were screened in renal cortex tissues from 3 CGN rats and 3 control rats by using high-throughput sequencing (HTS). Then, 4 circRNAs were selected randomly for verification by quantitative real-time polymerase chain reaction (qRT-PCR). In addition, the differentially expressed (DE) circRNAs were analyzed by bioinformatics methods.

RESULTS

In total, 31 significantly DE circRNAs were identified, which revealed their potential roles in CGN; in particular, we found that 4 confirmed altered circRNAs (rno-circ-RNAs 689, 3217, 1327, and 5001) might play important roles in the development of CGN.

CONCLUSION

This study reveals a cluster of circRNAs that are DE in Adriamycin-induced CGN rats, which brings us closer to understanding the pathogenic mechanisms and may provide new potential targets for clinical treatment.

Human FAM3C restores memory-based thermotaxis of Caenorhabditis elegans famp-1/m70.4 loss-of-function mutants

The family with sequence similarity 3 (FAM3) superfamily represents a distinct class of signaling molecules that share a characteristic structural feature. Mammalian FAM3 member C (FAM3C) is abundantly expressed in neuronal cells and released from the synaptic vesicle to the extracellular milieu in an activity-dependent manner. However, the neural function of FAM3C has yet to be fully clarified. We found that the protein sequence of human FAM3C is similar to that of the N-terminal tandem domains of Caenorhabditis elegans FAMP-1 (formerly named M70.4), which has been recognized as a tentative ortholog of mammalian FAM3 members or protein-O-mannose β-1,2-N-acetylglucosaminyltransferase 1 (POMGnT1). Missense mutations in the N-terminal domain, named Fam3L2, caused defects in memory-based thermotaxis but not in chemotaxis behaviors; these defects could be restored by AFD neuron-specific exogenous expression of a polypeptide corresponding to the Fam3L2 domain but not that corresponding to the Fam3L1. Moreover, human FAM3C could also rescue defective thermotaxis behavior in famp-1 mutant worms. An in vitro assay revealed that the Fam3L2 and FAM3C can bind with carbohydrates, similar to the stem domain of POMGnT1. The athermotactic mutations in the Fam3L2 domain caused a partial loss-of-function of FAMP-1, whereas the C-terminal truncation mutations led to more severe neural dysfunction that reduced locomotor activity. Overall, we show that the Fam3L2 domain-dependent function of FAMP-1 in AFD neurons is required for the thermotaxis migration of C. elegans and that human FAM3C can act as a substitute for the Fam3L2 domain in thermotaxis behaviors.

The ILEI/LIFR complex induces EMT via the Akt and ERK pathways in renal interstitial fibrosis

BACKGROUND

Chronic kidney disease (CKD) is characterized by high morbidity and mortality and is difficult to cure. Renal interstitial fibrosis (RIF) is a major determinant of, and commonly occurs within, CKD progression. Epithelial mesenchymal transition (EMT) has been identified as a crucial process in triggering renal interstitial fibrosis (RIF). Interleukin-like EMT inducer (ILEI) is an important promotor of EMT; this study aims to elucidate the mechanisms involved.

METHODS

Male C57BL6/J mouse were randomly divided into 6 groups: sham (n = 10), sham with negative control (NC) shRNA (sham + NC, n = 10), sham with ILEI shRNA (sham + shILEI, n = 10), unilateral ureteral obstruction (UUO, n = 10), UUO with NC (UUO + NC, n = 10) and UUO with ILEI shRNA (UUO + shILEI, n = 10). Hematoxylin and eosin (H&E), Masson, and immunohistochemical (IHC) staining and western blotting (WB) were performed on murine kidney tissue to identify the function and mechanism of ILEI in RIF. In vitro, ILEI was overexpressed to induce EMT in HK2 cells and analyzed via transwell, WB, real-time PCR, and co-immunoprecipitation. Finally, tissue from 12 pediatric CKD patients (seven with RIF and five without RIF) were studied with H&E, Masson, and IHC staining.

RESULTS

Our in vitro model revealed that ILEI facilitates RIF in the UUO model via the Akt and ERK pathways. Further experiments in vivo and in vitro revealed that ILEI promotes renal tubular EMT by binding and activating leukemia inhibitory factor receptor (LIFR), in which phosphorylation of Akt and ERK is involved. We further find markedly increased expression levels of ILEI and LIFR in kidneys from pediatric CKD patients with RIF.

CONCLUSION

Our results indicate that ILEI may be a useful biomarker for renal fibrosis and a potential therapeutic target for modulating RIF.

TGF-β1 Signaling: Immune Dynamics of Chronic Kidney Diseases

Chronic kidney disease (CKD) is a major cause of morbidity and mortality worldwide, imposing a great burden on the healthcare system. Regrettably, effective CKD therapeutic strategies are yet available due to their elusive pathogenic mechanisms. CKD is featured by progressive inflammation and fibrosis associated with immune cell dysfunction, leading to the formation of an inflammatory microenvironment, which ultimately exacerbating renal fibrosis. Transforming growth factor β1 (TGF-β1) is an indispensable immunoregulator promoting CKD progression by controlling the activation, proliferation, and apoptosis of immunocytes via both canonical and non-canonical pathways. More importantly, recent studies have uncovered a new mechanism of TGF-β1 for de novo generation of myofibroblast via macrophage-myofibroblast transition (MMT). This review will update the versatile roles of TGF-β signaling in the dynamics of renal immunity, a better understanding may facilitate the discovery of novel therapeutic strategies against CKD.

PTPRA facilitates cancer growth and migration via the TNF-α-mediated PTPRA-NF-κB pathway in MCF-7 breast cancer cells

Protein tyrosine phosphatase receptor type A (PTPRA), one of the classic protein tyrosine phosphatases, is crucial for modulating tumorigenesis and metastasis in breast cancer; however, its functional mechanism has not fully elucidated. The present study assessed PTPRA expression and estimated its clinical impact on survival using the Gene Expression Profiling Interactive Analysis database (GEPIA). Growth curves, colony formations and Transwell assays were utilized to examine cell proliferation and migration. Additionally, luciferase reporter assays were used to examine the potential tumor signaling pathways targeted by PTPRA in HEK293T cells. Furthermore, quantitative PCR (qPCR) was utilized to confirm the transcriptional regulation of PTPRA expression. Bioinformatic analyses of data from GEPIA identified PTPRA overexpression in patients with breast cancer. The growth curve, colony formation and transwell experiments demonstrated that PTPRA upregulation significantly promoted the cell proliferation and migration of MCF-7 breast cancer cells. In contrast, PTPRA knockdown significantly attenuated cell proliferation and migration. Mechanistic experiments revealed that the transcriptional activity of NF-κB was higher compared with other classic tumor pathways when they were activated by PTPRA in HEK293T cells. Furthermore, the transcriptional activity of NF-κB was altered in a PTPRA-dose-dependent manner. Additionally, following exposure to TNF-α, PTPRA-deficient MCF-7 cells exhibited lower NF-κB transcriptional activity compared with normal control cells. The results of the present study demonstrate that PTPRA overexpression accelerates inflammatory tumor phenotypes in breast cancer and that the TNF-α-mediated PTPRA-NF-κB pathway may offer novel insight into early diagnosis and optimum treatment for breast cancer.

MicroRNA-140-5p Mediates Renal Fibrosis Through TGF-β1/Smad Signaling Pathway by Directly Targeting TGFBR1

Renal tubulointerstitial fibrosis is usually the final outcome of various end-stage renal diseases. Recent studies have reported that microRNAs (miRNAs) play an important role in renal fibrosis. However, the biological function of microRNAs in renal fibrosis is complicated and remains unclear. In this study, our results show that miR-140-5p expression is significantly down-regulated in mice with unilateral ureteral obstruction and human proximal tubule epithelial cells (HK2) treated with TGF-β1. The knockdown of miR-140-5p upregulates the expression levels of collagen I, collagen IV, and α-SMA, decreases E-cadherin expression, and increases Smad-2/3 phosphorylation. In contrast, the overexpression of miR-140-5p decreases the expression levels of collagen I, collagen IV, and α-SMA, enhances E-cadherin expression, and inhibits the phosphorylation of Smad-2/3 in HK2 cells treated with TGF-β1. The dual-luciferase reporter assay revealed that TGFBR1 is a direct target gene of miR-140-5p. The enforced expression of miR-140-5p significantly inhibited the expression of TGFBR1 in HK2 cells. Furthermore, the knockdown of TGFBR1 has a similar effect of miR-140-5p overexpression on blocking the TGF-β1/smad signal pathway activation. In contrast, the overexpression of TGFBR1 reverses the effect of miR-140-5p inhibition on the activation of the TGF-β1/smad signal pathway. This study demonstrates that miR-140-5p regulates the TGF-β1/smad signaling pathway by suppressing the expression of TGFBR1. Therefore, miR-140-5p may have a therapeutic potential for preventing fibrotic kidney diseases through inhibiting the TGF-β1/Smad signaling pathway by directly targeting TGFBR1.

Elevated FAM3C promotes cell epithelial- mesenchymal transition and cell migration in gastric cancer

Background

Tumor metastasis is an important factor in treatment failure for advanced gastric cancer. Family with sequence similarity 3 member C (FAM3C) is known to play a critical role in inducing epithelial–mesenchymal transition in several cancer types, while its role in gastric cancer is unidentified. The aim of this study was to investigate the role of FAM3C in gastric cancer and provide new information on the receptor tyrosine-kinase pathway and cytokine-based therapies.

Methods

FAM3C expression was tested in human gastric cancer tissue and adjacent normal mucosa, and the prognostic effect of FAM3C was analyzed in data from the Cancer Genome Atlas (TCGA). The role of FAM3C in gastric cancer proliferation and metastasis was investigated in vitro and in vivo. Western blot analysis and immunofluorescence were used to detect the underlying mechanisms.

Results

FAM3C expression was increased in gastric cancer tissue and showed cytoplasmic distribution. Gastric cancer patients with FAM3C overexpression had significantly worse prognoses based on TCGA data. In the gastric cancer cell lines MKN45 and AGS, knockdown of FAM3C dramatically attenuated cell migration, but had almost no influence on proliferation, while exogenous FAM3C promoted cell migration in a cell line with low FAM3C expression. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of TCGA data showed that FAM3C was mainly associated with genes involved in focal adhesion, extracellular matrix–receptor interactions and the PI3K–Akt signaling pathway. Knockdown of FAM3C in gastric cancer cell lines significantly suppressed epithelial–mesenchymal transition, as demonstrated by increased expression of E-cadherin and decreased expression of Snail and Slug. Furthermore, knockdown of FAM3C strongly suppressed activation of the PI3K–Akt signaling pathway. Finally, we confirmed that FAM3C knockdown significantly decreased metastatic lesions in vivo.

Conclusion

Our study demonstrated that FAM3C can promote gastric cancer metastasis both in vitro and in vivo. FAM3C should be taken into consideration for gastric cancer treatments involving inhibition of the ligands and downstream pathways of receptor tyrosine kinases.

Interleukin-like EMT inducer (ILEI) promotes melanoma invasiveness and is transcriptionally up-regulated by upstream stimulatory factor-1 (USF-1)

Interleukin-like EMT inducer (ILEI, FAM3C) is a secreted factor that contributes to the epithelial-to-mesenchymal transition (EMT), a cell-biological process that confers metastatic properties to a tumor cell. However, very little is known about how ILEI is regulated. Here we demonstrate that ILEI is an in vivo regulator of melanoma invasiveness and is transcriptionally up-regulated by the upstream stimulatory factor-1 (USF-1), an E-box-binding, basic-helix-loop-helix family transcription factor. shRNA-mediated knockdown of ILEI in melanoma cell lines attenuated lung colonization but not primary tumor formation. We also identified the mechanism underlying ILEI transcriptional regulation, which was through a direct interaction of USF-1 with the ILEI promoter. Of note, stimulation of endogenous USF-1 by UV-mediated activation increased ILEI expression, whereas shRNA-mediated USF-1 knockdown decreased ILEI gene transcription. Finally, we report that knocking down USF-1 decreases tumor cell migration. In summary, our work reveals that ILEI contributes to melanoma cell invasiveness in vivo without affecting primary tumor growth and is transcriptionally up-regulated by USF-1.