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Breast cancer is a highly heterogeneous tumor, among which triple negative breast cancer (TNBC) is the most invasive and prone to recurrence and metastasis. The present study aimed to investigate the regulatory mechanisms of glutamate-rich WD-repeat-containing protein 1 (GRWD1) in TNBC cells. The expression of GRWD1 in the normal human breast epithelial cells and human breast cancer cells was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. The transfection effects of small interfering RNA (siRNA)-GRWD1 and overexpression (Ov)-Notch1 were also confirmed by RT-qPCR and western blotting. The proliferation, apoptosis, invasion and migration of transfected cells were in turn analyzed by Cell Counting Kit-8, 5-Ethynyl-2'-deoxyuridine, Matrigel and wound healing assays. The expression of proteins related to proliferation, apoptosis, metastasis, epithelial-mesenchymal transition and the Notch signaling pathway was detected by western blotting. As a result, GRWD1 expression was upregulated in breast cancer cells and was revealed to be highest in MDA-MB-231 and HCC1937 cells. GRWD1 knockdown suppressed TNBC cell proliferation, invasion and migration and promoted TNBC cell apoptosis. Furthermore, the expression of Notch1 and Notch4 was inhibited by GRWD1 knockdown. The expression of downstream genes of the Notch signaling pathway Hes1, Hes5, Hey1, Hey2, p21, c-Myc, cyclin D1, human epidermal growth factor 2 receptor and NF-κB were all suppressed after siRNA-GRWD1 transfection. However, Notch1 overexpression reversed the effect of GRWD1 knockdown on biological behaviors of TNBC cells. In conclusion, GRWD1 knockdown could suppress the proliferation, invasion and migration and promoted apoptosis of TNBC cells through inhibiting the Notch signaling pathway. Show less

A 70-year-old woman with complaints of edema, general malaise, and hypotension was diagnosed with renal amyloidosis, and laser microdissection mass spectrometry revealed her amyloidosis to predominantly comprise the apolipoprotein A-IV type. The M-protein turned from negative to positive during the course, and a bone marrow biopsy showed smoldering myeloma. Treatment with bortezomib and dexamethasone failed to save her from heart failure six months after the onset. Western blotting of urine samples at the time of the renal biopsy showed that amyloid light-chain κ amyloidosis had been present since the onset. Unlike the myeloma, Congo red staining was positive in the plasma cells of the bone marrow. Show less

Cyclic adenosine monophosphate-responsive element-binding protein H (CREBH) activates lipoprotein lipase (LPL) activity by modulating apolipoproteins. Activated LPL hydrolyzes triglyceride-rich lipoproteins, such as very low-density lipoprotein (VLDL) and chylomicrons, resulting in remnant lipoproteins. CREBH increases apolipoprotein E (ApoE), a ligand that mediates the clearance of remnant particles and reduces ApoC3, which interferes with remnant clearance. CREBH also improves VLDL receptor (VLDLR) and LDL receptor-related protein 1 (LRP1) protein that mediates remnant clearance. Therefore, CREBH promotes the clearance of remnant particles from the blood, decreasing the atherogenic plaque area. CREBH induces the secretion of fibroblast growth factor 21 (FGF21) into the blood, decreasing plasma triglyceride. CREBH produces ApoA1 and so increases plasma HDL-cholesterol levels. Show less

Sudden cardiac death (SCD), based on sudden cardiac ejection cessation, is an unexpected death. Primary cardiomyopathies, including dilated cardiomyopathy (DCM), are one of main causes of SCD. The DCM is characterized by a cardiac dilatation and a reduced systolic function with a prevalence of 1/250 in adults. The DCM has been reported with more than 60 disease-causing genes, and We identified a 29-year-old female who died of SCD. We performed a whole-exome sequencing (WES) to detect her genetic etiology and used minigene modeling and immunohistochemistry staining to verify the pathogenicity. We determined that the woman died of SCD caused by DCM due to an identified novel synonymous variant of We may have identified the first deleterious synonymous variant of Show less

Parkinson's disease may be caused by a single pathogenic variant (monogenic) in 5-10% of cases, but investigation of these disorders provides valuable pathophysiological insights. In this review, we discuss each genetic form with a focus on genotype, phenotype, pathophysiology, and the geographic and ethnic distribution. Well-established Parkinson's disease genes include autosomal dominant forms ( Show less

WWP2 is a HECT E3 ligase that targets protein Lys residues for ubiquitination and is comprised of an N-terminal C2 domain, four central WW domains, and a C-terminal catalytic HECT domain. The peptide segment between the middle WW domains, the 2,3-linker, is known to autoinhibit the catalytic domain, and this autoinhibition can be relieved by phosphorylation at Tyr369. Several protein substrates of WWP2 have been identified, including the tumor suppressor lipid phosphatase PTEN, but the full substrate landscape and biological functions of WWP2 remain to be elucidated. Here, we used protein microarray technology and the activated enzyme phosphomimetic mutant WWP2 Show less

Circular RNAs (circRNAs) are non-coding RNAs with covalently closed structures that modulate the progression of hepatocellular carcinoma (HCC). Here, we explored whether circ₀₀₀₈₀₄₃ regulated the biological function of HCC cells. Quantitative real-time polymerase chain reaction (qPCR) was used to detect circ₀₀₀₈₀₄₃, microRNA (miR)-326, and RAB21 levels. Expression of E-cadherin, N-cadherin, and vimentin was assessed using qPCR. Cell proliferation, migration, and invasion were evaluated using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, and transwell assays. Xenograft tumors were used to evaluate cell growth Show less

Schistosomiasis is a life-threatening parasitic disease caused by blood flukes, Schistosomes. In its intestinal type, the parasites reside in visceral/portal veins of the human hosts and lay eggs to excrete in feces Show less

This study summarises the diagnostic validity and clinical utility of genetic testing for patients with hypertrophic cardiomyopathy (HCM) and their at-risk relatives. A systematic search was performed in PubMed (MEDLINE), Embase, CINAHL and Cochrane Central Library databases from inception through 2 March 2020. Subgroup and sensitivity analyses were prespecified for individual sarcomere genes, presence/absence of pathogenic variants, paediatric and adult cohorts, family history, inclusion of probands, and variant classification method. Study quality was assessed using the Newcastle-Ottawa tool. A total of 132 articles met inclusion criteria. The detection rate based on pathogenic and likely pathogenic variants was significantly higher in paediatric cohorts compared with adults (56% vs 42%; p=0.01) and in adults with a family history compared with sporadic cases (59% vs 33%; p=0.005). When studies applied current, improved, variant interpretation standards, the adult detection rate significantly decreased from 42% to 33% (p=0.0001) because less variants met criteria to be considered pathogenic. The mean difference in age-of-onset in adults was significantly earlier for genotype-positive versus genotype-negative cohorts (8.3 years; p<0.0001), This systematic review and meta-analysis is the first, to our knowledge, to collectively quantify historical understandings of detection rate, genotype-phenotype associations and disease penetrance for HCM, while providing the answers to important routine clinical questions and highlighting key areas for future study. Show less

Hepatocellular carcinoma (HCC) is one of the most prevalent malignant tumors with poor prognosis. Increasing evidence has revealed that immune cells and checkpoints in the tumor microenvironment (TME) and aging are associated with the prognosis of HCC. However, the association between aging and the tumor immune microenvironment (TIME) in HCC is still unclear. RNA expression profiles and clinical data concerning HCC were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Based on differentially expressed aging-related genes (DEAGs), unsupervised clustering was used to identify a novel molecular subtype in HCC. The features of immune cell infiltration and checkpoints were further explored through CIBERSORTx. Enrichment analysis and both univariate and multivariate Cox analyses were conducted to construct a 3-gene model for predicting prognosis and chemosensitivity. Finally, the mRNA and protein expression levels of the 3 genes were verified in HCC and other cancers through database searches and experiments. Eleven differentially expressed AGs (GHR, APOC3, FOXM1, PON1, TOP2A, FEN1, HELLS, BUB1B, PPARGC1A, PRKDC, and H2AFX) correlated with the prognosis of HCC were used to divide HCC into two subtypes in which the prognosis was different. In cluster 2, which had a poorer prognosis, the infiltration of naive B cells and monocytes was lower in the TCGA and GEO cohorts, while the infiltration of M0 macrophages was higher. In addition, the TCGA cohort indicated that the microenvironment of cluster 2 had more immunosuppression through immune checkpoints. Enrichment analysis suggested that the MYC and E2F targets were positively associated with cluster 2 in the TCGA and GEO cohorts. Additionally, 3 genes (HMGCS2, SLC22A1, and G6PD) were screened to construct the prognostic model through univariate/multivariate Cox analysis. Then, the model was validated through the TCGA validation set and GEO dataset (GSE54236). Cox analysis indicated that the risk score was an independent prognostic factor and that patients in the high-risk group were sensitive to multiple targeted drugs (sorafenib, gemcitabine, rapamycin, etc.). Finally, significantly differential expression of the 3 genes was detected across cancers. We systematically described the immune differences in the TME between the molecular subtypes based on AGs and constructed a novel three-gene signature to predict prognosis and chemosensitivity in patients with HCC. Show less

Aberrant DNA methylation patterns, including hypermethylation of key genes that inhibit fibrosis and inflammation, have been described in human kidney diseases. However, the role of DNA methyltransferase 1 (DNMT1) in hepatitis B virus-associated glomerulonephritis (HBV-GN) remains unclear. We explored the underlying mechanism by establishing HBV X protein (HBx) overexpressing renal tubular epithelial (HK-2) cells and human podocytes with DNMT1 knockdown. Using RNA-sequencing to determine the downstream targets of DNMT1 and evaluate its levels of promoter methylation. HBV transgenic mice were used to examine the effects of DNMT1 inhibitor on renal in vivo. DNMT1 was significantly upregulated in the renal tissue of HBV-GN patients, accompanied by injuries of HK-2 cells and podocytes. HBx markedly upregulated DNMT1 and induced epithelial-mesenchymal transition (EMT) and inflammation in HK-2 cells and human podocytes. This increased DNMT1 expression was attenuated after DNMT1 knockdown, accompanied by restored HK-2 cells and podocyte injuries resulting from the activation of PI3K/Akt/mTOR and nuclear factor-kappa B (NF-κB) pathways. Hypermethylation of the phosphatase and tensin homolog (PTEN) promoter and vitamin D receptor (VDR) was induced in HBx-overexpressing HK-2 cells and podocytes, respectively, whereas DNMT1 knockdown effectively corrected these alterations. Furthermore, PTEN and VDR ablation resulted in marked EMT and inflammation induction in HBx-overexpressing HK-2 cells and human podocytes even with DNMT1 knockdown. Downregulation of the PI3K/Akt/mTOR-related pathway attenuated HBx-induced EMT and inflammation in HK-2 cells. Luciferase reporter assay revealed VDR as a direct target of the Snail family transcriptional repressor 1 (SNAI1) in HBx-overexpressing podocytes. DNA methylation inhibitor 5-azacytidine alleviated urinary protein and renal inflammation in HBV transgenic mice via PTEN-PI3K/Akt signaling and VDR signaling axis. Our study clarifies the potential epigenetic mechanisms underlying HBx-induced renal injuries in HBV-GN and the renoprotective effects of inhibiting DNMT1, which can provide important insights into the development of treatments for HBV-GN. Show less

The leiomodin1 (LMOD1) gene, encoding a potent actin nucleator, was recently reported as a potential pathogenic gene of megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS, OMIM 619362). However, only a single patient has been reported to have LMOD1 mutations, and the underlying pathogenic mechanism remains unknown. Here, we described a male infant with LMOD1 mutations presenting typical symptoms of pediatric intestinal pseudo-obstruction (PIPO) but without megacystis and microcolon. Two compound heterozygous missense variants (c.1106C>T, p.T369M; c.1262G>A, p.R421H) were identified, both affecting highly conserved amino acid residues within the second actin-binding site (ABS2) domain of LMOD1. Expression analysis showed that both variants resulted in significantly reduced protein amounts, especially for p.T369M, which was almost undetectable. The reduction was only partially rescued by the proteasome inhibitor MG-132, indicating that there might be proteasome-independent pathways involved in the degradation of the mutant proteins. Molecular modeling showed that variant p.T369M impaired the local protein conformation of the ABS2 domain, while variant p.R421H directly impaired the intermolecular interaction between ABS2 and actin. Accordingly, both variants significantly damaged LMOD1-mediated actin nucleation. These findings provide further human genetic evidence supporting LMOD1 as a pathogenic gene underlying visceral myopathy including PIPO and MMIHS, strengthen the critical role of ABS2 domain in LMOD1-mediated actin nucleation, and moreover, reveal an unrecognized role of ABS2 in protein stability. Show less

Non-ischemic cardiomyopathy (NICM) can cause left ventricular dysfunction through interstitial fibrosis, which corresponds to the failure of cardiac tissue remodeling. Recent evidence implicates monocytes/macrophages in the etiopathology of cardiac fibrosis, but giving their heterogeneity and the antagonizing roles of macrophage subtypes in fibrosis, targeting these cells has been challenging. Here we focus on WWP2, an E3 ubiquitin ligase that acts as a positive genetic regulator of human and murine cardiac fibrosis, and show that myeloid specific deletion of WWP2 reduces cardiac fibrosis in hypertension-induced NICM. By using single cell RNA sequencing analysis of immune cells in the same model, we establish the functional heterogeneity of macrophages and define an early pro-fibrogenic phase of NICM that is driven by Ccl5-expressing Ly6c Show less

Organotropism during cancer metastasis occurs frequently but the underlying mechanism remains poorly understood. Here, we show that lysosomal protein transmembrane 5 (LAPTM5) promotes lung-specific metastasis in renal cancer. LAPTM5 sustains self-renewal and cancer stem cell-like traits of renal cancer cells by blocking the function of lung-derived bone morphogenetic proteins (BMPs). Mechanistic investigations showed that LAPTM5 recruits WWP2, which binds to the BMP receptor BMPR1A and mediates its lysosomal sorting, ubiquitination and ultimate degradation. BMPR1A expression was restored by the lysosomal inhibitor chloroquine. LAPTM5 expression could also serve as an independent predictor of lung metastasis in renal cancer. Lastly, elevation of LAPTM5 expression in lung metastases is a common phenomenon in multiple cancer types. Our results reveal a molecular mechanism underlying lung-specific metastasis and identify LAPTM5 as a potential therapeutic target for cancers with lung metastasis. Show less

Differentiation blockade is a hallmark of acute myeloid leukemia (AML). A strategy to overcome such a blockade is a promising approach against the disease. The lack of understanding of the underlying mechanisms hampers development of such strategies. Dysregulated ribonucleotide reductase (RNR) is considered a druggable target in proliferative cancers susceptible to deoxynucleoside triphosphate (dNTP) depletion. Herein, we report an unanticipated discovery that hyperactivating RNR enables differentiation and decreases leukemia cell growth. We integrate pharmacogenomics and metabolomics analyses to identify that pharmacologically (eg, nelarabine) or genetically upregulating RNR subunit M2 (RRM2) creates a dNTP pool imbalance and overcomes differentiation arrest. Moreover, R-loop-mediated DNA replication stress signaling is responsible for RRM2 activation by nelarabine treatment. Further aggravating dNTP imbalance by depleting the dNTP hydrolase SAM domain and HD domain-containing protein 1 (SAMHD1) enhances ablation of leukemia stem cells by RRM2 hyperactivation. Mechanistically, excessive activation of extracellular signal-regulated kinase (ERK) signaling downstream of the imbalance contributes to cellular outcomes of RNR hyperactivation. A CRISPR screen identifies a synthetic lethal interaction between loss of DUSP6, an ERK-negative regulator, and nelarabine treatment. These data demonstrate that dNTP homeostasis governs leukemia maintenance, and a combination of DUSP inhibition and nelarabine represents a therapeutic strategy. Show less

Immunotherapy targeting checkpoint blockade to rescue T cells from exhaustion has become an essential therapeutic strategy in treating cancers. Till now, little is known about the PD-L1 graphic pattern and characteristics in CD8 Show less

The liver is the center for uptake, synthesis, packaging, and secretion of lipids and lipoproteins. The research on lipid metabolism in pigs is limited. The objective of the present study is to identify the genes related to lipid metabolism and oxidative stress in pigs by using transcriptomic analysis. Liver segments were collected from 60 Jinhua pigs for the determination of liver lipid content. The 7 pigs with the highest and lowest liver lipid content were set as group H and group L, respectively. Liver segments and serum samples were collected from each pig of the H and L groups for RNA sequencing and the determination of triglycerides (TG) content and high-density lipoprotein cholesterol (HDL) content, respectively. The HDL content in the serum of pigs in the H group was significantly higher than the L group ( Show less

Atorvastatin is commonly used medication to achieve low levels of low-density lipoproteins (LDL). Cholesteryl ester transfer protein ( One hundred and 50 blood samples were collected from hyperlipidemic patients in the University of Jordan Hospital. Polymerase chain reaction-restriction fragment length polymorphism was used for genotyping of LDLR Results demonstrated a significant association between the Show less

The brain renin-angiotensin system (RAS) is implicated in control of blood pressure (BP), fluid intake, and energy expenditure (EE). Angiotensin II (ANG II) within the arcuate nucleus of the hypothalamus contributes to control of resting metabolic rate (RMR) and thereby EE through its actions on Agouti-related peptide (AgRP) neurons, which also contribute to EE control by leptin. First, we determined that although leptin stimulates EE in control littermates, mice with transgenic activation of the brain RAS (sRA) exhibit increased EE and leptin has no additive effect to exaggerate EE in these mice. These findings led us to hypothesize that leptin and ANG II in the brain stimulate EE through a shared mechanism. Because AgRP signaling to the melanocortin MC Show less

Understanding the mechanisms underlying malignancy in myeloma cells is important for targeted treatment and drug development. Histone deacetylases (HDACs) can regulate the progression of various cancer types; however, their roles in myeloma are not well known. In the present study, the expression of class I HDACs in myeloma cells and tissues was evaluated. Furthermore, the effects of HDAC1 on the migration of myeloma cells and the associated mechanisms were investigated. Among the class I HDACs evaluated, HDAC1 was upregulated in both myeloma cells and tissues. Targeted inhibition of HDAC1 suppressed the migration of myeloma cells. Of the assessed transcription factors, small interfering (si)‑HDAC1 decreased the expression of Slug. Overexpression of Slug reversed the si‑HDAC1‑mediated suppressed migration of myeloma cells. Mechanistically, the results revealed that HDAC1 regulated the mRNA stability of Slug, while it had no effect on its transcription or nuclear export. Furthermore, HDAC1 negatively regulated the expression of long non‑coding RNA (lncRNA) NONHSAT113026, which could bind with the 3'‑untranslated region of Slug mRNA to facilitate its degradation. The present study demonstrated that HDAC1 promoted the migration of human myeloma cells via regulation of lncRNA/Slug signaling. Show less

Recent advances in genetic analysis have significantly helped in progressively attenuating the heritability gap of obesity and have brought into focus monogenic variants that disrupt the melanocortin signaling. In a previous study, next-generation sequencing revealed a monogenic etiology in ∼50% of the children with severe obesity from a consanguineous population in Pakistan. Here we assess rare variants in obesity-causing genes in young adults with severe obesity from the same region. Genomic DNA from 126 randomly selected young adult obese subjects (BMI 37.2 ± 0.3 kg/m2; age 18.4 ± 0.3 years) was screened by conventional or augmented whole-exome analysis for point mutations and copy number variants (CNVs). Leptin, insulin, and cortisol levels were measured by ELISA. We identified 13 subjects carrying 13 different pathogenic or likely pathogenic variants in LEPR, PCSK1, MC4R, NTRK2, POMC, SH2B1, and SIM1. We also identified for the first time in the human, two homozygous stop-gain mutations in ASNSD1 and IFI16 genes. Inactivation of these genes in mouse models has been shown to result in obesity. Additionally, we describe nine homozygous mutations (seven missense, one stop-gain, and one stop-loss) and four copy-loss CNVs in genes or genomic regions previously linked to obesity-associated traits by genome-wide association studies. Unexpectedly, in contrast to obese children, pathogenic mutations in LEP and LEPR were either absent or rare in this cohort of young adults. High morbidity and mortality risks and social disadvantage of children with LEP or LEPR deficiency may in part explain this difference between the two cohorts. Show less

Gastric cancer is a heterogeneous disease associated to deregulated gastric epithelia tight junction barrier function and di novo expression of claudin-6; these changes are associated with epithelial-mesenchymal transition, enhanced invasiveness, metastatic progression, resistance to chemotherapy, and poor prognosis. Gastric cancer stem cells represent a rare population of cells within the tumor implicated in tumor growth and higher tumorigenic capacity. The possible relation between claudin-6 expression and the expression of some markers associated to epithelial mesenchymal transition and cancer stem cells in gastric cancer cells have never been explored. CD44, CD24, Twist, Villin, DCLK1, claudin-6, NANOG, E-Cadherin, SOX2, and SNAI1 expression was evaluated by immunofluorescence and cytofluorometry in wild type and Claudin-6 transfected AGS cells. Cell migration assays were also performed. Differentially expressed genes and biological processes analysis was performed to determine gene preponderance. The results showed that claudin-6 overexpression enriched the CD44 + /CD24- subpopulation with an overall increase in the expression and the number of CD44 + cells. A significant increase in NANOG, SOX2 and SNAI1 expression and enhanced cell migration was observed in claudin-6 transfected cells. Transcriptome analysis revealed 271 genes involved in enhanced biological processes with only 31 with a significantly p value; thirteen of those genes are closely associated to epithelial mesenchymal transition processes and folding and unfolding processes of proteins in the endoplasmic reticulum. The pro-tumorigenic effect of claudin-6 in gastric cancer could be associated to dedifferentiation of epithelial cells and an increase in di novo cancer stem cell genesis. Show less

PCBP-1, a multifunctional RNA binding protein, is expressed in various human cell/tissue types and involved in post-transcriptional gene regulation. PCBP-1 has important roles in cellular Iron homeostasis, mitochondrial stability, and other cellular activities involved in the pathophysiological process of neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD). However, it remains enigmatic whether PCPB-1 is associated with the pathogenesis of PD. In this study, we cloned and constitutively overexpressed PCBP-1 in rat PC12 cells (PC12 cell is the common cell line studying neurodegenerative disease include PD). RNA-seq was performed to analyze PCBP-1-regulated differentially expressed genes (DEGs) and alternative splicing events (ASEs) between control and PCBP1-overexpressed cells. GO and KEGG pathway analyses were performed to identify functional DEGs and alternatively spliced genes. Consequently, we validated PCBP-1-regulated genes using RT-qPCR. Finally, we downloaded CLIP-seq data from GEO (GSE84700) to analyze the mechanisms of PCBP-1's regulation of gene expression and ASEs by revealing the binding profile of PCBP-1 on its target pre-mRNAs. Overexpression of PCBP-1 partially regulated the ASE and expression of genes enriched in neuroinflammation and protein ubiquitination, which were also associated with PD pathogenesis. Moreover, RT-qPCR assay verified the PCBP-1-modulated expression of neuroinflammatory genes, like Show less

Primary focal segmental glomerulosclerosis (FSGS), along with minimal change disease (MCD), are diseases with primary podocyte damage that are clinically manifested by the nephrotic syndrome. The pathogenesis of these podocytopathies is still unknown, and therefore, the search for biomarkers of these diseases is ongoing. Our aim was to determine of the proteomic profile of urine from patients with FSGS and MCD. Patients with a confirmed diagnosis of FSGS (n = 30) and MCD (n = 9) were recruited for the study. For a comprehensive assessment of the severity of FSGS a special index was introduced, which was calculated as follows: the first score was assigned depending on the level of eGFR, the second score-depending on the proteinuria level, the third score-resistance to steroid therapy. Patients with the sum of these scores of less than 3 were included in group 1, with 3 or more-in group 2. The urinary proteome was analyzed using liquid chromatography/mass spectrometry. The proteome profiles of patients with severe progressive FSGS from group 2, mild FSGS from group 1 and MCD were compared. Results of the label free analysis were validated using targeted LC-MS based on multiple reaction monitoring (MRM) with stable isotope labelled peptide standards (SIS) available for 47 of the 76 proteins identified as differentiating between at least one pair of groups. Quantitative MRM SIS validation measurements for these 47 proteins revealed 22 proteins with significant differences between at least one of the two group pairs and 14 proteins were validated for both comparisons. In addition, all of the 22 proteins validated by MRM SIS analysis showed the same direction of change as at the discovery stage with label-free LC-MS analysis, i.e., up or down regulation in MCD and FSGS1 against FSGS2. Patients from the FSGS group 2 showed a significantly different profile from both FSGS group 1 and MCD. Among the 47 significantly differentiating proteins, the most significant were apolipoprotein A-IV, hemopexin, vitronectin, gelsolin, components of the complement system (C4b, factors B and I), retinol- and vitamin D-binding proteins. Patients with mild form of FSGS and MCD showed lower levels of Cystatin C, gelsolin and complement factor I. Show less