Identification of a Novel miR-195-5p/PNN Axis in Colorectal Cancer.

Pinin (PNN) is a desmosome-associated protein that reinforces the organization of keratin intermediate filaments and stabilizes the anchoring of the cytoskeleton network to the lateral surface of the plasma membrane. The aberrant expression of PNN affects the strength of cell adhesion as well as modifies the intracellular signal transduction pathways leading to the onset of CRC. In our previous studies, we characterized the role of miR-195-5p in the regulation of desmosome junctions and in CRC progression. Here, with the aim of investigating additional mechanisms related to the desmosome complex, we identified PNN as a miR-195-5p putative target. Using a public data repository, we found that PNN was a negative prognostic factor and was overexpressed in colon cancer tissues from stage 1 of the disease. Then, we assessed PNN expression in CRC tissue specimens, confirming the overexpression of PNN in tumor sections. The increase in intracellular levels of miR-195-5p revealed a significant decrease in PNN at the mRNA and protein levels. As a consequence of PNN regulation by miR-195-5p, the expression of KRT8 and KRT19, closely connected to PNN, was affected. Finally, we investigated the in vivo effect of miR-195-5p on PNN expression in the colon of AOM/DSS-treated mice. In conclusion, we have revealed a new mechanism driven by miR-195-5p in the regulation of desmosome components, suggesting a potential pharmacological target for CRC therapy.

miR-195-5p as Regulator of γ-Catenin and Desmosome Junctions in Colorectal Cancer.

Desmosomes play a key role in the regulation of cell adhesion and signaling. Dysregulation of the desmosome complex is associated with the loss of epithelial cell polarity and disorganized tissue architecture typical of colorectal cancer (CRC). The aim of this study was to investigate and characterize the effect of miR-195-5p on desmosomal junction regulation in CRC. In detail, we proposed to investigate the deregulation of miR-195-5p and JUP, a gene target that encodes a desmosome component in CRC patients. JUP closely interacts with desmosomal cadherins, and downstream, it regulates several intracellular transduction factors. We restored the miR-195-5p levels by transient transfection in colonic epithelial cells to examine the effects of miR-195-5p on JUP mRNA and protein expression. The JUP regulation by miR-195-5p, in turn, determined a modulation of desmosome cadherins (Desmoglein 2 and Desmocollin 2). Furthermore, we focused on whether the miR-195-5p gain of function was also able to modulate the expression of key components of Wnt signaling, such as NLK, LEF1 and Cyclin D1. In conclusion, we have identified a novel mechanism controlled by miR-195-5p in the regulation of adhesive junctions, suggesting its potential clinical relevance for future miRNA-based therapy in CRC.

Downregulation of γ-Catenin by miR-195-5p Inhibits Colon Cancer Progression, Regulating Desmosome Function.

Desmosomes are essential structures for ensuring tissue functions, and their deregulation is involved in the development of colorectal cancer (CRC). JUP (γ-catenin) is a desmosome adhesion component that also acts as a signaling hub, suggesting its potential involvement in CRC progression. In this context, we recently demonstrated that miR-195-5p regulated JUP and desmosome cadherins expression. In addition, miR-195-5p gain of function indirectly modulated the expression of key effectors of the Wnt pathway involved in JUP-dependent signaling. Here, our purpose was to demonstrate the aberrant expression of miR-195-5p and JUP in CRC patients and to functionally characterize the role of miR-195-5p in the regulation of desmosome function. First, we showed that miR-195-5p was downregulated in CRC tumors compared to adjacent normal tissue. Then, we demonstrated that JUP expression was significantly increased in CRC tissues compared to adjacent normal tissues. The effects of miR-195-5p on CRC progression were assessed using in vitro transient transfection experiments and in vivo miRNA administration. Increased miR-195-5p in colonic epithelial cells strongly inhibits cell proliferation, viability, and invasion via JUP. In vivo gain of function of miR-195-5p reduced the numbers and sizes of tumors and significantly ameliorated the histopathological changes typical of CRC. In conclusion, our findings indicate a potential pharmacological target based on miR-195-5p replacement as a new therapeutic approach in CRC.

Artificial Intelligence and Complex Network Approaches Reveal Potential Gene Biomarkers for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and the number of cases is constantly increasing. Early and accurate HCC diagnosis is crucial to improving the effectiveness of treatment. The aim of the study is to develop a supervised learning framework based on hierarchical community detection and artificial intelligence in order to classify patients and controls using publicly available microarray data. With our methodology, we identified 20 gene communities that discriminated between healthy and cancerous samples, with an accuracy exceeding 90%. We validated the performance of these communities on an independent dataset, and with two of them, we reached an accuracy exceeding 80%. Then, we focused on two communities, selected because they were enriched with relevant biological functions, and on these we applied an explainable artificial intelligence (XAI) approach to analyze the contribution of each gene to the classification task. In conclusion, the proposed framework provides an effective methodological and quantitative tool helping to find gene communities, which may uncover pivotal mechanisms responsible for HCC and thus discover new biomarkers.

The Increase of miR-195-5p Reduces Intestinal Permeability in Ulcerative Colitis, Modulating Tight Junctions' Expression.

Defects in the intestinal epithelial barrier functions characterize inflammatory conditions such as Inflammatory Bowel Disease (IBD). Overexpression of pro-inflammatory cytokines such as TNF-α, IL-1B, IL-6 and INF-γ trigger epithelial damage. These cytokines are due to upregulation of claudin-2 (CLDN2) that form a pore channel, resulting in redistribution of TJs and an alteration of barrier permeability. Recently, we demonstrated that miR-195-5p is able to regulate CLDN2 and indirectly also CLDN1 in intestinal epithelial cells. Now, we aimed to investigate the modulation of miR-195-5p on the expression of CLDN2 and other TJs under inflammatory conditions induced by TNF-α. We demonstrated that miR-195-5p also modulated the expression of CLDN2 levels after stimulation with TNF-α. In addition, we discovered the role of miR-195-5p in the integrity of the intestinal barrier and in promoting the restoration of the intestinal epithelial. Moreover, we established that replacement of miR-195-5p attenuated the colonic inflammatory response in DSS-induced, colitis and it reduced colonic permeability. In conclusion, our data revealed the role of miR-195-5p in intestinal inflammation in ulcerative colitis, suggesting a potential pharmacological target for new therapeutic approaches.

A Novel Mechanism of Immunoproteasome Regulation via miR-369-3p in Intestinal Inflammatory Response.

The immunoproteasome is a multi-catalytic protein complex expressed in hematopoietic cells. Increased expression of immuno-subunits followed by increased proteasome activities is associated with the pathogenesis of IBD. Therefore, the identification of molecules that could inhibit the activities of this complex has been widely studied. microRNAs are small molecules of non-coding RNA that regulate the expression of target genes. Our purpose was to demonstrate that miR-369-3p is able to reduce the expression of the PSMB9 subunit and consequently modulate the catalytic activities of immunoproteasome. After bioinformatics prediction of the gene target of miR-369-3p, we validated its modulation on PSMB9 expression in the RAW264.7 cell line in vitro. We also found that miR-369-3p indirectly reduced the expression of other immunoproteasome subunits and that this regulation reduced the catalytic functions of the immunoproteasome. Increased levels of PSMB9 were observed in colon samples of acute IBD patients compared to the remission IBD group and control group. Our data suggest that miR-369-3p may be a future alternative therapeutic approach to several compounds currently used for the treatment of inflammatory disorders including IBD.

The Tumor Microenvironment Drives Intrahepatic Cholangiocarcinoma Progression.

Intrahepatic cholangiocarcinoma (iCCA) is a highly aggressive cancer with limited therapeutic options and short overall survival. iCCA is characterized by a strong desmoplastic reaction in the surrounding ecosystem that likely affects tumoral progression. Overexpression of the Notch pathway is implicated in iCCA development and progression. Our aim was to investigate the effectiveness of Crenigacestat, a selective inhibitor of NOTCH1 signaling, against the cross-talk between cancer cells and the surrounding ecosystem in an in vivo HuCCT1-xenograft model. In the present study, a transcriptomic analysis approach, validated by Western blotting and qRT-PCR on iCCA tumor masses treated with Crenigacestat, was used to study the molecular pathways responsive to drug treatment. Our results indicate that Crenigacestat significantly inhibited NOTCH1 and HES1, whereas tumor progression was not affected. In addition, the drug triggered a strong immune response and blocked neovascularization in the tumor ecosystem of the HuCCT1-xenograft model without affecting the occurrence of fibrotic reactions. Therefore, although these data need further investigation, our observations confirm that Crenigacestat selectively targets NOTCH1 and that the desmoplastic response in iCCA likely plays a key role in both drug effectiveness and tumor progression.

Identification of SLC15A4/PHT1 Gene Products Upregulation Marking the Intestinal Epithelial Monolayer of Ulcerative Colitis Patients.

SLC15A4/PHT1 is an endolysosome-resident carrier of oligopeptides and histidine recently come into view as a key path marker of immune/autoimmune/inflammatory pathways in immune cells. Yet, its emerging role in inflammatory processes directly targeting the gastrointestinal epithelial layer, as in the multifactorial pathophysiology of inflammatory bowel disease (IBD), is poorly investigated. Here, the first identification of SLC15A4/PHT1 gene products in human colonic epithelium of ulcerative colitis (UC) patients is reported, showing protein primarily localized in intracellular vesicle-like compartments. Qualitative and quantitative immunohistochemical analyses of colon biopsies revealed overexpression of SLC15A4/PHT1 protein product in the epithelial layer of UC patients. Results were successfully mirrored in vitro, in spontaneously differentiated enterocyte-like monolayers of Caco-2 cells specifically exposed to DSS (dextran sodium sulphate) to mimic IBD inflammatory onsets. SLC15A4/PHT1 expression and cellular localization were characterized confirming its (dys)regulation traits in inflamed vs. healthy epithelia, strongly hinting the hypothesis of SLC15A4/PHT1 increased function associated with epithelial inflammation in IBD patients.

Assessment and management of undifferentiated carcinoma with osteoclastic like giant cells of the pancreas: a case report and revision of literature.

BACKGROUND: Undifferentiated carcinoma with osteoclast-like giant cells (UCOGCs) is a rare and aggressive non endocrine pancreatic carcinoma characterized by the presence of osteoclastic giant cells mixed with mononuclear cell. Very few cases have been reported in the literature and the histogenesis is controversial as, at the time of diagnosis, the tumor is often of advanced size and stage and it is difficult to pathologically observe its relationship with the pancreatic duct. CASE PRESENTATION: We present a case of 65-year-old male patient presenting with abdominal pain, nausea, and weight loss, which was treated with surgical resection. Histological examination revealed an undifferentiated pancreatic carcinoma with osteoclast-like giant cells. The patient underwent to a routine pylorus preserving pancreatoduodenectomy. Actually, the patient was in good performance status and disease-free five months. CONCLUSIONS: Based on the present case and limited previous data, further researches preferably with large cohorts are necessary to clarify the pathogenesis of the neoplasm. However, as show in this case, histopathological and immunohistochemically studies are the gold standard for the diagnosis of UCPOGC. Investigation of the genomic alterations in UPOGCs could help to explain the histologic diversity of variant tumor and could provide a genetic basis for prognosis and treatment.

Direct and Indirect Effect of TGFß on Treg Transendothelial Recruitment in HCC Tissue Microenvironment.

The balance between anti-tumor and tumor-promoting immune cells, such as CD4+ Th1 and regulatory T cells (Tregs), respectively, is assumed to dictate the progression of hepatocellular carcinoma (HCC). The transforming growth factor beta (TGFß) markedly shapes the HCC microenvironment, regulating the activation state of multiple leukocyte subsets and driving the differentiation of cancer associated fibroblasts (CAFs). The fibrotic (desmoplastic) reaction in HCC tissue strongly depends on CAFs activity. In this study, we attempted to assess the role of TGFß on transendothelial migration of Th1-oriented and Treg-oriented CD4+ T cells via a direct or indirect, CAF-mediated mechanisms, respectively. We found that the blockage of TGFß receptor I-dependent signaling in Tregs resulted in impaired transendothelial migration (TEM) of these cells. Interestingly, the secretome of TGFß-treated CAFs inhibited the TEM of Tregs but not Th1 cells, in comparison to the secretome of untreated CAFs. In addition, we found a significant inverse correlation between alpha-SMA and FoxP3 (marker of Tregs) mRNA expression in a microarray analysis involving 78 HCCs, thus suggesting that TGFß-activated stromal cells may counteract the trafficking of Tregs into the tumor. The apparent dual behavior of TGFß as both pro- and anti-tumorigenic cytokines may add a further level of complexity to the mechanisms that regulate the interactions among cancerous, stromal, and immune cells within HCC, as well as other solid tumors, and contribute to better manipulation of the TGFß signaling as a therapeutic target in HCC patients.

Role of microRNAs in the Regulation of Dendritic Cell Generation and Function.

Dendritic cells (DCs) are antigen-presenting cells with a key role in immune responses. They act as a link between the innate and adaptive systems and they can induce and maintain immunologic tolerance. DCs are subdivided into conventional and plasmacytoid DCs. These cell subsets originate from the same bone marrow precursors and their differentiation process is determined by several extrinsic and intrinsic factors, such as cytokines, transcription factors, and miRNAs. miRNAs are small non-coding RNAs that play a crucial role in modulating physiological and pathological processes mediated by DCs. miRNA deregulation affects many inflammatory conditions and diseases. The aim of this review was to underline the importance of miRNAs in inflammatory processes mediated by DCs in physiological and pathological conditions and to highlight their potential application for future therapies.

Iron Overload Mimicking Conditions Skews Bone Marrow Dendritic Cells Differentiation into MHCIIlowCD11c+CD11b+F4/80+ Cells.

Iron overload is an undesired effect of frequent blood transfusions or genetic diseases. Myelodysplastic syndrome (MDS) patients become transfusion dependent, but due to the combination of ineffective haematopoiesis and repeated blood transfusions they are often subject to iron overload. In this study, we demonstrate that iron-overload mimicking condition alters bone marrow progenitor differentiation towards dendritic cells (DCs). Cells cultured in iron-enriched culture medium for seven days fail to differentiate into conventional CD11c+MHCIIhi DCs and fail to efficiently respond to LPS (Lipopolysaccharides). Cells appear smaller than control DCs but vital and able to perform FITC-dextran (Fluorescein isothiocyanate-dextran) endocytosis. At molecular level, cells cultured in iron-enriched conditions show increased ARG1 and PU.1, and decreased IRF8 expression.

Winnie-APCMin/+ Mice: A Spontaneous Model of Colitis-Associated Colorectal Cancer Combining Genetics and Inflammation.

(1) Background: Colorectal cancer (CRC) is among the best examples of the relationship between inflammation and increased cancer risk. (2) Methods: To examine the effects of spontaneous low-grade chronic inflammation on the pathogenesis of CRC, we developed a new murine model of colitis-associated cancer (CAC) by crossing Mucin 2 mutated mice (Winnie) with ApcMin/+ mice. (3) Results: The resulting Winnie-ApcMin/+ model combines an inflammatory background with a genetic predisposition to small intestinal polyposis. Winnie-ApcMin/+ mice show an early occurrence of inflammatory signs and dysplastic lesions in the distal colon with a specific molecular signature. (4) Conclusion: The Winnie-ApcMin/+ model is a perfect model to demonstrate that chronic inflammation represents a crucial risk factor for the onset and progression of tumoral lesions in individuals genetically predisposed to CRC.

Quercetin Exposure Suppresses the Inflammatory Pathway in Intestinal Organoids from Winnie Mice.

Inflammatory bowel diseases (IBDs) are chronic and relapsing immune disorders that result, or possibly originate, from epithelial barrier defects. Intestinal organoids are a new reliable tool to investigate epithelial response in models of chronic inflammation. We produced organoids from the ulcerative colitis murine model Winnie to explore if the chronic inflammatory features observed in the parental intestine were preserved by the organoids. Furthermore, we investigated if quercetin administration to in vitro cultured organoids could suppress LPS-induced inflammation in wild-type organoids (WT-organoids) and spontaneous inflammation in ulcerative colitis organoids (UC-organoids). Our data demonstrate that small intestinal organoids obtained from Winnie mice retain the chronic intestinal inflammatory features characteristic of the parental tissue. Quercetin administration was able to suppress inflammation both in UC-organoids and in LPS-treated WT-organoids. Altogether, our data demonstrate that UC-organoids are a reliable experimental system for investigating chronic intestinal inflammation and pharmacological responses.

Omics studies for comprehensive understanding of immunoglobulin A nephropathy: state-of-the-art and future directions.

Immunoglobulin A nephropathy (IgAN) is the most common worldwide primary glomerulonephritis with a strong autoimmune component. The disease shows variability in both clinical phenotypes and endpoints and can be potentially subdivided into more homogeneous subtypes through the identification of specific molecular biomarkers. This review focuses on the role of omics in driving the identification of potential molecular subtypes of the disease through the integration of multilevel data from genomics, transcriptomics, epigenomics, proteomics and metabolomics. First, the identification of molecular biomarkers, including mapping of the full spectrum of common and rare IgAN risk alleles, could permit a more precise stratification of IgAN patients. Second, the analysis of transcriptomic patterns and their modulation by epigenetic factors like microRNAs has the potential to increase our understanding in the pathogenic mechanisms of the disease. Third, the specificity of urinary proteomic and metabolomic signatures and the understanding of their functional relevance may contribute to the development of new non-invasive biomarkers for a better molecular characterization of the renal damage and its follow-up. All these approaches can give information for targeted therapeutic decisions and will support novel clinical decision making. In conclusion, we offer a framework of omic studies and outline barriers and potential solutions that should be used for improving the diagnosis and treatment of the disease. The ongoing decade is exploiting novel high-throughput molecular technologies and computational analyses for improving the diagnosis (precision nephrology) and treatment (personalized therapy) of the IgAN subtypes.

In a retrospective international study, circulating miR-148b and let-7b were found to be serum markers for detecting primary IgA nephropathy.

Immunoglobulin A nephropathy (IgAN) is a worldwide disease characterized by the presence of galactose-deficient IgA1 deposits in the glomerular mesangium. A kidney biopsy for diagnosis is required. Here, we measured two miRNAs (let-7b and miR-148b), previously identified as regulators of the O-glycosylation process of IgA1, in serum samples from patients with IgAN and healthy blood donors (controls) recruited in an international multicenter study. Two predictive models, based on these miRNAs, were developed and the diagnostic accuracy of the combined biomarkers was assessed by the area under the receiver operating characteristic (ROC) curve (AUC) carried out in three steps. In a training study, the combined miRNAs were able to discriminate between 100 patients with IgAN and 119 controls (AUC, 0.82). A validation study confirmed the model in an independent cohort of 145 patients with IgAN and 64 controls (AUC, 0.78). Finally, in a test study, the combined biomarkers were able to discriminate patients with IgAN from 105 patients affected by other forms of primary glomerulonephritis, supporting the specificity (AUC, 0.76). Using the same study design, we also performed two subgroup analyses (one for Caucasians and one for East Asians) and found that race-specific models were the best fit to distinguish IgAN patients from controls. Thus, serum levels of the combined miRNA biomarker, let-7b and miR-148b, appears to be a novel, reliable, and noninvasive test to predict the probability of having IgAN.

Aberrantly methylated DNA regions lead to low activation of CD4+ T-cells in IgA nephropathy.

IgAN (IgA nephropathy) is the most common form of primary glomerulonephritis worldwide and has a strong genetic component. In this setting, DNA methylation could also be an important factor influencing this disease. We performed a genome-wide screening for DNA methylation in CD4(+) T-cells from IgAN patients and found three regions aberrantly methylated influencing genes involved in the response and proliferation of CD4(+) T-cells. Two hypomethylated regions codified genes involved in TCR (T-cell receptor) signalling, TRIM27 (tripartite motif-containing 27) and DUSP3 (dual-specificity phosphatase 3), and an hypermethylated region included the VTRNA2-1 (vault RNA 2-1) non-coding RNA, also known as miR-886 precursor. We showed that the aberrant methylation influences the expression of these genes in IgAN patients. Moreover, we demonstrated that the hypermethylation of the miR-886 precursor led to a decreased CD4(+) T-cell proliferation following TCR stimulation and to the overexpression of TGFß (transforming growth factor ß). Finally, we found a Th1/Th2 imbalance in IgAN patients. The IL (interleukin)-2/IL-5 ratio was notably higher in IgAN patients and clearly indicated a Th1 shift. In conclusion, we identified for the first time some specific DNA regions abnormally methylated in IgAN patients that led to the reduced TCR signal strength of the CD4(+) T-cells and to their anomalous response and activation that could explain the T-helper cell imbalance. The present study reveals new molecular mechanisms underlying the abnormal CD4(+) T-cell response in IgAN patients.

Potential role of effector memory T cells in chronic T cell-mediated kidney graft rejection.

BACKGROUND: Chronic T cell-mediated rejection (TCMR) in kidney graft is characterized by reduction of the vessel lumen with marked intimal thickening, fibrous hyperplasia of the small renal arteries and leukocyte infiltrates. The aim of this study was to find specific gene expression profiles in chronic TCMR kidney biopsies. METHODS: RNA extracted from archival formalin-fixed, paraffin-embedded renal biopsies was used for gene expression profiling. Our study included 14 patients with chronic TCMR and 10 with acute TCMR. Fifty-two cadaveric donors were used as controls. The results were validated in an independent set of kidney biopsies. RESULTS: We identified 616 and 243 differentially expressed genes with a fold change ≥1.5 and a false discovery rate <0.05 in chronic and acute TCMR, respectively. Pathway analysis revealed upregulation of OX40 signalling. This pathway is involved in the generation of CD8+ effector memory T cells and the upregulation of killer cell lectin-like receptor G1 (KLRG-1), B lymphocyte-induced maturation protein 1 (BLIMP-1) and CD25, which characterize CD8+ effector memory T cells. However, the enhanced OX40 signalling pathway was specific to chronic TCMR; a significant increase of KLRG-1+/CD8+ and BLIMP-1+/CD8+ was only detected in these specimens. CONCLUSIONS: These results suggest the involvement of memory-committed CD8+ effector T cells in chronic TCMR. The generation of effector memory T cells is mediated by the OX40 gene pathway, and could be considered a future target for the specific treatment of chronic TCMR.

microRNAs in glomerular diseases from pathophysiology to potential treatment target.

miRNAs are regulators of gene expression in diverse biological and pathological courses in life. Their discovery may be considered one of the most important steps in the story of modern biology. miRNAs are packed within exosomes and released by cells for cellular communications; they are present in bodily fluids. Their study opens the way for understanding the pathogenetic mechanisms of many diseases; furthermore, as potential candidate biomarkers, they can be measured in bodily fluids for non-invasive monitoring of disease outcomes. The present review highlights recent advances in the role of miRNAs in the pathogenesis of primary and secondary glomerulonephritides such as IgA nephropathy, focal segmental glomerular sclerosis, lupus nephritis and diabetic nephropathy. The identification of reciprocal expression of miRNAs and their target genes provides the molecular basis for additional information on the pathogenetic mechanisms of kidney diseases. Finally, recent findings demonstrate that miRNAs can be considered as potential targets for novel drugs.

Altered monocyte expression and expansion of non-classical monocyte subset in IgA nephropathy patients.

BACKGROUND: The main defect of immunoglobulin A nephropathy (IgAN) lies within the immune system and in peripheral blood mononuclear cells rather than in the kidney. Previously, we found an altered gene expression in monocytes compared with B and T cells isolated from IgAN patients; thus, our aim here has been to study this subset at a genome-wide and functional level. METHODS: A total of 39 IgAN patients and 37 healthy blood donors (HBDs) were included in this study, and microarray technology was used to evaluate global gene expression differences in monocytes isolated from IgAN patients and HBDs. Aberrantly expressed genes and pathways were then validated on an independent set of IgAN patients with RT-PCR western blot and flow cytometric analysis. RESULTS: Gene expression differences in monocytes from IgAN patients and HBDs primarily involved apoptosis signalling, mitochondrial dysfunction, tnfr2/1 and death receptor signalling. Both the extrinsic and intrinsic apoptotic pathways seem to be implicated; in particular, the protein levels of NDUFS3 and TNFRSF1A were upregulated thus confirming the altered mitochondrial and death receptor homeostasis. Furthermore, the basal intracellular protein levels of TNF in monocytes were lower in IgAN patients compared with HBDs. We validated at protein level an enhanced apoptotic phenotype and a different subset distribution in monocytes from IgAN patients. We found that the non-classical monocyte subset (CD14(+)CD16(+)) was significantly expanded in all IgAN patients tested even though the total monocyte count remained unchanged. CONCLUSIONS: Our findings demonstrate, for the first time, an aberrant modulation of the mitochondrial respiratory system in monocytes isolated from IgAN patients. Furthermore, the aberrant expansion of the (CD14(+)CD16(+)) subset could explain the enhanced apoptotic phenotype seen in these cells thus revealing their potential role in the pathogenesis of IgAN.